A glimpse of the latest Nanox.Arc

Two new photos of Nanox.Arc were posted yesterday on twitter, but it is unclear when those were taken, by whom, and why the resolution is so bad.

The device is in the same shielded room used for the RSNA 2020 demo.  It appears the device still needs a HUGE external high-voltage generator, but it is unclear what tubes (size and specs), if any, are inside the Arc.  It is also weird that there are three persons sitting at the consoles, but there is nothing to be scanned on the "bed."  The device looks unsafe - what happens, if a patient hand (or long hair) gets stuck between the moving table and the moving Arc?

Korean math, again

Another non-sensical fluff piece sponsored by Nanox:

Nanox said that its Yongin plant will be annually producing 220,000 MEMS chips, enough to make 50,000 Nanox.ARC devices. The temporary facility in Cheongju currently has a monthly production capacity of 1,000 MEMS chips.

That is interesting.  220,000 divided by 50,000 is 4.4.  In other words, each Arc device will have 4 tubes and another very special partial ( 4/10, exactly) tube, just short of the 5 tubes in the investor presentations.   Also, Nanox has not disclosed any plans to make 50,000 Arc devices (only 15,000 by 2024).

The capacity is also wrong  - it was supposed to be 120,000 (based on the 10,000 a month from inventor presentations).

Here is the Korean text, in case of doubt.

The equipment shown in the article's photo appears to be Precision 5000 by Applied Materials, an almost 40-year-old CVD machine - baking the very innovative fake Nanox.Source!  Let me know, if I am mistaken.  

A confused press release by Nanox points to fraud

Yesterday Nanox issued a press release and filed a 6-K about its premarket submission to the FDA for a device called Nanox.Arc.  The press release contradicts numerous claims made by Nanox in the past, and contains at least one red herring.

510(k) means the device is not novel

Nanox had repeatedly claimed in the past that the Nanox.Arc device is novel.  Here is another instance, not covered previously:

Nanox.ARC, in collaboration with its companion cloud-based software Nanox.Cloud, is a novel digital x-ray device intended to provide end-to-end medical imaging services ..., according to Nanox founder and CEO Ran Poliakine.

Here is another:

...to use the Nanox ARC system on site for developing novel early-detection and screening protocols to promote global preventive healthcare practices.

The problem is a that a novel device, by definition, cannot be cleared.  Clearance aka pre-market submission aka 510(k) submission is simply a submission made to the FDA to demonstrate that the device to be marketed is as safe and effective, that is, substantially equivalent, to a legally marketed device (section 513(i)(1)(A) FD&C Act) - definitely not novel.  The FDA explains:  

Novel devices include those brought to market through the premarket approval (PMA), humanitarian device exemption (HDE), and De Novo pathways, as well as a subset of those that are brought to market with 510(k) clearance or Emergency Use Authorization (EUA). Of the thousands of 510(k) clearances every year, the FDA considers only those devices with a breakthrough designation to be novel. In addition, in 2020, we are including first-of-a-kind devices authorized under our EUA authority as novel devices. Novel or innovative does not simply mean “new.” They address an unmet need, or may be safer or more effective than currently available alternatives. For FDA-approved and FDA-cleared medical devices, innovation, and safety are two sides of the same coin.

Nanox has not requested a breakthrough device designation.  The 510(k) submission therefore contradicts the claim that Nanox.Arc is novel.

510(k) confirms the RSNA 2020 demo was illegal

Nanox claims to have demonstrated Nanox.Arc version 2.0 at the "virtual" RSNA 2020 trade show last December.  Today's press release confirms the device had no clearance pending at the time of the demo.  This article explains:

A device that lacks FDA marketing clearance is considered "investigational," and therefore the company cannot promote, advertise or accept orders for it. The FDA considers such activities to be “commercialization of an unapproved device." The FDA does make some exceptions for trade shows, however,... [only if the device] is the subject of a pending 510(k) application. It cannot take orders or be prepared to take orders that might result in contracts for sale for the device unless limited to research or investigational use.”

So, since the submission was announced just yesterday, there was no clearance pending in December, which means the device was marketed illegally in December.

This can't be the first version of the "multi-source" Nanox.Arc

According to Nanox technology webpage, the first version of the multi-source Nanox.Arc looks like this:

That device is completely fake.  It is has no x-ray tube, no x-ray detector, no ability to scan - in fact, it is just a mock-up plus an LED light and a battery.  Version 1.5 on that webpage does not look less fake.

At RSNA 2020, Nanox CEO insisted that the design of the multi-source Nanox.Arc has been finalized (in its version 2) - he was just confused whether the device had 5 or 6 x-ray tubes:

The design was changed again in February 2021 - version 2.5? - and the device had no x-ray tubes or a detector.

The device, even if cleared, is not meant for shipping

The press release states:

We are excited to take this next step in our regulatory process as we move toward future versions of the multi-source Nanox.ARC, which will fulfill current and future contracts with service providers and collaboration agreements and allow us to achieve our global vision.

Apparently, the device, as submitted for clearance, is not meant to be delivered or commercialized.  So, why has then Nanox submitted a pre-market notification, that is 510(k)?  Why hasn't Nanox submitted a device that can actually be used? 

 

Nanox.Arc can scan only one human "body part"

The press release states:

Nanox.ARC is a 3-D tomosynthesis imaging system that produces scans of a human body part.  

Just one "body part?"  Which one?  There aren't many "body parts" that can be properly imaged in the supine or prone position using 3-D tomosynthesis.  None are considered "usually appropriate" by the American College of Radiology Appropriateness Criteria.

The "a" is a subtle change from the "the" on page 62 in the annual report, where Nanox claims:

 

Subject to receiving regulatory clearance, the first version of the multi-source Nanox.ARC that we expect to introduce to the market is expected to be a 3D tomosynthesis imaging system that produces a 3D reconstruction of the scanned human body part...

Not much use for a device that can image only one human body part, even if the device were available for free.  

Tomosynthesis is a failed modality

The press release claims there

 

exists a significant unmet medical need globally for a more accessible and cost-effective medical imaging solution

Presumably, a tomosynthesis device like the proposed Nanox.Arc could meet that need.  However,  tomosynthesis is a failed modality, with possible exception of digital breast tomosynthesis (DBT), which Nanox.Arc cannot do due to its design.  Tomosynthesis (also known as tomography, not to be confused with CT or computed tomography) has existed since the 1930s in one shape or another, but its share (DBT excluded) has been less than 1% of unit shipments of diagnostic x-ray devices in the United States and probably even less in the world (based on a preliminary and unpublished analysis of FDA's x-ray assembler data files).  Yes, it is cheap (maybe 10-20% more expensive than plain old x-ray devices - sometimes just a software update is required), but from diagnostic point of view, it is not much better than taking two or three plain radiographs, and it cannot compete with the "gold standards" such as CT or other non-x-ray technologies.

Nanox.Arc is not designed for easy setup and operation

The press release states:

The system is being designed for easy setup and operation with multiple alternately-switched X-ray tubes arranged around the patient.

However, the RSNA 2020 demo revealed that the device requires an external high-voltage generator.  Also, the annual report states that need for 

potential customers to invest in the required safety infrastructure, including customary X-ray shielding, to allow the Nanox.ARC to be safety operated.

The device, as demoed at RSNA 2020, is slow.  The scan of a simple "body part," a phantom hand, took about 45 seconds.  Imagine holding your breath or lying completely still for 45 seconds to prevent image blurring.

The single-source Nanox.Arc transformed into Nanox.Cart

The press release reiterates:

Nanox received FDA clearance of its single source Nanox Cart X-Ray System in April 2021

But that April clearance was initially supposed to be for the single-source Nanox.Arc (Prospectus, Page 1).  To this date, Nanox has never shown a picture or photo of the "Nanox Cart X-Ray System" anywhere.

Nanox has not developed a commercial-grade digital X-ray source

The press states that Nanox 

is developing a commercial-grade digital X-ray source designed to be used in real-world medical imaging applications

In other words, it has not developed it yet.  So what x-ray sources are used by Nanox.Arc, the one just submitted for clearance?  All signs point to regular (but poorly crafted) hot-cathode x-ray tubes.  

The press release never mentions any cold-cathode x-ray tubes.  The cold cathode is supposedly the core Nanox innovation, but the CEO is apparently unware that x-rays were discovered in 1895 using a cold-cathode x-ray tube. and that tube was completely driven off the market by the invention of the hot-cathode tube in 1913 by GE. 

Just too good to be true

Steven Koepke, who goes by koepkesd @ Stocktwits and Steven @ Yahoo, has been busy reading this blog while trying to justify the lies by the Nanox CEO that somehow the $200 (or $100, depending on the day) Nanox.Tube can replace the $150,000 modern CT tube (these are "list prices," of course).

For the longest time I was trying to figure out how Ran can claim that his field emitting device (FED) can generate x-rays on par with the high end x-ray tubes used in CT machines. Those large tubes can generate 800 to 1,000 mA at 120 kV. They also cost $120,000-$150,000. Here is the math. The MEMS (FED) chip has an active area of 0.126cm^2 (4mm diameter on chip in diameter and the power level was communicated at 2.5A/cm^2. The power is concentrated down via focusing device onto the tungsten anode. The basic math provides the power of the beam to be 314mA and 120 kV (per conference call last week). That's quite close and running multiple sources in parallel amplifies the power. Cost comparison: 5 small tubes @ $100 vs $150,000 for singe large CT device tube. Micro-X has a similar arrangement working today with a CNT device (also Field Emitting Device)

 

So, what's wrong with his reasoning?

There is no such thing as a field emitting device.  FED refers to a failed display technology -  a field emitting DISPLAY.  It does not contain "a field" of emitters, as Nanox CEO believes - it emits electrons induced by an electrostatic field.  It is not a more efficient or a cooler way to generate x-rays - all x-ray tubes, whether using a cold cathode (based on the field effect) or a hot cathode (using a hot filament) to emit electrons, have about 1% efficiency as 99% of the energy applied to the tube gets wasted as heat at the anode.  A hot filament uses a lower voltage - about 4V - than the 40V (or way more) needed by a cold cathode.  Roentgen discovered x-rays in 1895 using a cold-cathode (gas discharge) tube.  GE invented the hot-cathode x-ray tube in 1913 and obliterated the cold-cathode ones.

The proposed Nanox.Source chip is not MEMS, as there is nothing mechanical about it.  The chip is not real, or commercially available, of course, as Nanox has no ability to manufacture it commercially, at least not yet.

The current density of 2.5A/cm^2 comes from a fraudulent, that is, intentionally misleading, 2015 datasheet by Nanox predecessor, which I have previously linked here on this blog. 

The Nanox.Tube cannot do 314mA and 120 kVp.  The one used in the Nanox.Cart can do up to 2mA and up to 40 kVp, at most (or 0.08 kW, per 510K summary).  The CEI one can do up to 1mA and up to 100 kVp (or something like 0.1 kW, per CEI video).  The tube used by GE in the predicate device for Nanox.Cart can do about 40 kW - it has a rotating anode.  The CT tube can do about 120 kW (using Steven's numbers). So, to replicate the power of a $150,000 CT tube, one needs to use, oh, something like 1,000-1,500 Nanox tubes that cost $100,000 or more.  An after-market CT tube will cost less than $100,000, of course.  All this has been already discussed last year.

Micro-X has a 4.8 kW tube (a bulky stationary-anode one) - it uses carbon nanotubes, which Nanox says is impossible - it sells a few units a year.  The biggest CEI tubes are smaller sizes than Micro-X's and go up to about 2.5 kW (also stationary-anode ones).  

Update June 10, 2021:  Investors will eventually blame Nanox CEO for their delusions.  Steven continues:

The anode temperature becomes the challenge with the NNOX tube. CEI states that their tubes can handle about 60KJ. The RSNA video shows the bed is moving through the sources quickly (15-20 seconds for whole body). My guess is that NNOX is using high current short bursts to keep the anode temperature under control. In the video they may have used 300mA for up to 0.2 seconds to make 10 shots (capturing 8" per shot) while the cart moves through. 300mA x 0.2 X 10 shots = 60KJ. You can't shot this with dental tubes like that. They don't have the current and the image gets too blurry.

He is right that a typical dental tube (which has a better performance than the Nanox tube) cannot do 300mA.  He is also right that at some point, the heat capacity of the anode becomes a challenge (the anode temperature is not really a problem - it is the temperature of a part of the anode, the tungsten target, that is the challenge).

But Steven does not understand what heat capacity means.  Yes, one of CEI's most powerful medical tubes, OX125-06, can handle 60 kJ (CEI only makes stationary-anode tubes).  But that does not mean that it can do 300 mA or that 300 mA  x 0.2 s  x 100 kVp  x 10 shots = 60 kJ.  Nor does it mean that you can do 5 A x 0.2 s  x 60 kVp x 1 shot.  CEI provides nice charts in its datasheets to explain the interplay between heat capacity, tube current, tube voltage, and time.

As the charts show, the tube cannot do more than 35mA at 60kVp for 0.1s or more than 20mA at 110 kVp for 0.1s. But it can do 15 mA at 100 kVp for 10 seconds.  The RSNS 2020 demo, which we now know was fake, never demonstrated a full-body scan - it scanned three phantom "organs." The "hand" scan consisted of 45 "shots" or images ( 5 tubes x 9 tilts/translations) - it took about 50 seconds for the images thumbnails to appear on the display.  That is about 1 second per shot, not 0.2 seconds (and we don't know what that's even real).

The CEI OX-70, a dental tube,  can do about 32mA at 60 kVp for 0.1s or more than 20mA at 90 kVp for 0.1s.  It can do 10mA at 90 kVp for 10 seconds.  Here is some summary table from CEI's datasheets.  Stationary-anode tubes all look kind of the same.  The tubes that do less than 100 kVp are "dental" and typically tolerate half the current than the "medical," and are a bit smaller. 

Model	Voltage  kVp	Current mA, 0.1s	Current mA, 100kV	Focal sp. (mm)	Diam. (mm)	Length (mm)
Small/Dental tubes
OX/70-P	70	19	N/A	0.8	30	72
OX/70-5	70	11	N/A	0.5	30	72
OCX/65-G	70	12	N/A	0.8	30	76
OX/70-4	70	9	N/A	0.4	30	72
OX/70	90	21	N/A	1.2	30	82
OX/90	90	9	N/A	0.5	30	83
OCX/70-G	70	12	N/A	0.8	30	65
OCX/70-G4	70	8	N/A	0.4	30	65
Medical/Mobile tubes
OPX/105	110	18	2.5	0.5	42	125
OPX/105-4	105	17	2.5	0.4	42	95
3D/cone-beam CT tubes
OCX/100	105	20	4	0.5	46	140
OX/100	100	26	1.5	1.0	35	85

Recall, the Nanox tube in Nanox.Cart can do only 2mA at 40 kVp (for 0.1s -1 s).  The CEI Nanox tube can do only 1 mA at 100 kVp for 40 seconds (per CEI video).  The CEI OX-70 dental tube can do about 40 mA at 40 kVp for 0.1s, about 25 mA at 40 kVp for 1s, and about 3 mA at 90 kVp for about 40 seconds (per datasheet charts).  If Nanox tubes perform like poorly-made hot-cathode dental tubes, they probably are.  No mystery Nanox.Source chip required.

Update June 10, 2021:   Just to clarify, regular dental tubes (just one or 5 ) can definitely replicate the fake RSNA 2020 Nanox.Arc demo.  The "hand" scan took about 50 seconds for 45 images.  Let's see whether a dental tube can do 45 images at 45 seconds, that is, a bit faster.  A CEI dental tube operating at 90 kVp can do 3mA continuously for 45 seconds, so each exposure (image) will be 3 mAs at 90 kVp.  The Nanox.Cart demo at RSNA 2020 image needed just 1.5 mAs at 40 kVp (so, significantly less than 1/4 of what the CEI dental tube can supply).  Commercial fluoroscopy equipment does ok with 100 kVp and 1 mAs for each frame (image) at 30 fps.  So, sure, with a good enough (expensive enough) detector, you can do the Nanox.Arc tomosynthesis within 45 seconds.  But the detector (regardless of the tubes used) won't cost anywhere near $10,000.  And no one would like to look at the images (the American College of Radiology never considers a tomosynthesis procedure to be "usually appropriate,"  except for breast, which the Arc cannot do).

If you build it, who will use it?

Nanox.Arc device, as it stands today, is fake.  But what if Nanox used its $200+ million cash to actually design and build its proposed device?  Will it be useful?

Nanox claims that its proposed device uses a modality ("imaging technique") - tomosynthesis - that is supposedly "widely used for early detection" of something.

Subject to receiving regulatory clearance, the first version of the Nanox.ARC that we expect to introduce to the market will be a 3D tomosynthesis imaging system. Tomosynthesis is an imaging technique widely used for early detection, that is designed to produce a high-resolution, 3D X-ray image reconstruction of the scanned human body part for review by a professional diagnostics expert (annual report, page 56)

Tomosynthesis (previously called x-ray tomography, focal plane tomography, etc) has been available since 1930s - it should not to be confused with CT or computed tomography, which can visualize axial slices and individual voxels.  

tomosynthesis vs. plain, per Nanox demo at RSNA 2020 

Even though various medical device manufacturers have pushed it over the years, its use has never been wide.  It never added much to simple x-rays taken from different views... 

In 1993, the American College of Radiology (ACR) started work on developing guidelines for radiology to eliminate inappropriate utilization of radiologic services.  Today,

ACR Appropriateness Criteria are evidence-based guidelines to assist referring physicians and other providers in making the most appropriate imaging or treatment decision for a specific clinical condition. Employing these guidelines helps providers enhance quality of care and contribute to the most efficacious use of radiology.

Of the nearly 1,000 radiological procedures covered by the criteria, only three are based on tomosynthesis, and all three involve breast tomosynthesis, which is usually appropriate for breast cancer screening and diagnosis:

• "Digital breast tomosynthesis diagnostic"
• "Digital breast tomosynthesis screening" 
• "Digital breast tomosynthesis short-interval follow-up"

Elsewhere, tomosynthesis is mentioned maybe a couple of times in the narrative discussion or literature search as part of the regular x-ray modality analysis (for example, here and here), but clearly it is not significant enough to deserve any attention as a specific imaging procedure indicated in specific diagnostic scenario.

The real problem is that the proposed Nanox.Arc cannot perform digital breast tomosynthesis, contrary to Nanox claims in March 2020 about no-squish mammography.  In its own mammography white paper, Nanox admits that breast tomosynthesis requires compression (squishing) and a completely different mechanical design, which makes scanning of other organs, such as lungs, impossible.

So here we have it.  According to the American College of Radiology evidence-based guidelines, the use of Nanox.Arc, as proposed, will not be "usually appropriate" under any clinical scenario.

Summary notes

The Summary of the 510(k) submission by Nanox for its Nanox.Cart device was published last week.  Here are some observations, in no particular order of importance (yet).

The name of the predicate device is wrong

The name of the predicate device, cleared under K021016, is AMX-4 Plus Mobile X-Ray System, not AMX-4 Mobile X-Ray System as claimed by the Summary.  What else is incorrect, if Nanox cannot even get the name of the predicate device right?  The "Plus" system is the upgraded model.  The predicate of the Plus model is AMX-3 Mobile X-ray System, K802047, another GE system.  The chair of Nanox Advisory Board is a former GE executive.

A micro-controller Arduino Mega 256 does not exist

Table 1 claims that Nanox.Cart uses a micro-controller Arduino Mega 256 that "controls the Nanox Cart X-ray System's functionality and GUI display."   No such micro-controller exists.  There is an Arduino Mega 2560 micro-controller board designed for hobbyists that uses the old and cheap ATmega2560 micro-controller released more than 15 years ago.  Quite novel.

The target angle of 0 degrees in Table 1 is non-sensical (a typo) and contradicts the 16 degrees value in Table 2

The target, or anode, angle is a very important characteristic of an x-ray tube, as it determines focal size and beam width, strength and composition.  At zero degrees, the tube will be completely unusable.  It is one mistake that Nanox should not have made, if its "X-ray source technology [were] the basis of [its] business" (page 9, annual report).

The maximum tube voltage for the predicate device in Table 1 is incorrect

Table 1 claims that the maximum tube voltage for the predicate device is 100 kV, which clearly contradicts the 125 kV value from the "kV range" section in the same table.  The actual value is 130 kV (from the tech specs of the HRT09 tube).

The power output of the reference device is annoying

Table 2 states that the power output of the reference device is 4.8 kW @ 104 msec, which is incorrect (a typo) and it should be "@100 msec," which is the standard (for example, IEC 60613:2010). 

The x-ray source used by Nanox.Cart is still a mystery

There is no mention in the summary of any of the non-sensical descriptions that Nanox typically uses for its proposed x-ray source - digital, MEMs, silicon, semi-conductor, novel, etc.   Table 2 claims that the "Nanox Tube" is similar to "Xinray CNT Tube," but that is incorrect based on the data in Table 2, as the CNT tube is 60x as powerful (4.8kW vs 0.08kW), capable of substantially higher tube voltage (110kVp vs 40kVp) and current.  Table 1 mentions that Nanox.Cart uses a "Nano-x's Cold Cathode tube" in the system description, but the tube type/model in both Table 1 and 2 is given as "Nanox Tube" (no cold-cathode here) and there is no tube model (Nanox' web site shows at least 4 completely different and incompatible "Nanox tubes" that look remarkably similar to regular industrial/dental hot-cathode tubes).

The mention of an x-ray source in the intended use is non-sensical

The description of the device's intended use begins with the non-sensical statement

The product is intended as an X-Ray source for diagnosis. 

The product is a mobile x-ray system - FDA product code IZL - not a x-ray source (which almost exclusively means an x-ray tube in the context of modern diagnostic equipment - other sources could be radioactive isotopes, synchrotrons, etc).  The product is supposed to include many more components other than an x-ray tube, as confirmed by the "system components" section in  Table 1, for example,  It appears this statement was intentionally inserted by Nanox to confuse investors and possibly subvert the 510(k) clearance process.

The single-source Nanox device is cleared only for hands, wrists, and fingers, on adult patients only

Both Table 1 and Table 2 claim that the intended use of the device is similar to that of the predicate and reference devices.  But that is incorrect and contradicts the actual description of the intended use, as the device is cleared for a very limited subset of examinations, while both the predicate and reference devices can do all general purpose X-ray diagnostic procedures.  In fact, the limitation for use explicitly states:

This device is not intended for general radiographic X-Ray examinations other than the indicated use...

So much for Nanox curing cancer.

The Nanox device is cleared to work with only one detector model, which appears unsuitable and has to be purchased separately

There is a bit of problem with the tech specs of the detector that Nanox has chosen to work with its device.  The summary states:

The Nanox Cart is specified and designed to operate only with a Flat Panel Digital X-ray Detector Model EVS3643, manufactured by DRTECH Inc.

The summary of the detector clearance specifies that the X-ray system using it must have tube voltage equal or higher to 40 kVp, so Nanox.Cart barely complies (its tube voltage is fixed at 40 kVp per Table 1 and 2). What is more troubling is that the generator "mA Range" used in the detector clearance is specified as "10mA ~ 1000mA," which Nanox Cart fails to meet, as it cannot deliver more than 2mA (implied by 0.08 kW power output and 40 kVp tube voltage).  

More importantly, this detector cannot be used for diagnostic purposes on a live subject by the proposed multi-source Nanox.Arc device, as it is too slow and takes about 5 seconds to capture and transfer an image.  A 45-image tomosynthesis of a wrist, for example, would take at least 4 minutes, if the RSNA 2020 demo were anywhere close to reality.

Finally, the lowest quote for this detector, obtained in the gray market - new, but from unauthorized distributors and without warranty - is about $20,000.  So much for being "cheap."

Many of the images supposedly made with the single-source device in the annual report and in investor presentations are likely fake

According to the annual report, 

[Nanox has] generated the images below with the Nanox.ARC using a single X-ray tube on an imaging phantom (page 61).

 

However, none of these images were generated by the device that received clearance, as the device tube voltage is limited to 40 kVp (so the 50 kVp tube voltage in the images is impossible).  Moreover, the device is not cleared for ankle/foot examinations.

Here is another image, from Nanox investor presentations, that is impossible to create by the device that got cleared.  

First, the device is not cleared for shoulder examinations.  Second, the 2.5mA reading exceeds the maximum device tube current of 2mA.

The mobility of the device is questionable

The device is cleared under the IZL product code, but it is not truly mobile/transportable.  The device description states:

The system facilitates X-ray examinations in situations where it is not possible or feasible to transport the patient to a ward with fixed equipment

But the device has no battery, unlike its predicate - it is as mobile as the length of the cord (less mobile than a regular vacuum cleaner). 

The device is "similar" to the predicate device, except that it is not

The section "Substantial Equivalence Discussion" is somewhat confusing.  The section argues that the device is equivalent except that it is not. 

The technical characteristics of the System are not different from the predicate device except for the fixed Source-to-image Distance, Field of view, aperture, focal spot size, and the fixed tube voltage and reduced maximum exposure current-time product. 

Virtually all technical characteristics of the two devices are significantly different, and, it can be argued, raise many questions of effectiveness.  Table 1, for example, confusingly states that the fixed tube voltage and current exposure time product (or charge) are similar to the significantly wider ranges that are needed in practice and can be obtained from the predicate device.  For example, typical "technique charts" for digital detectors stipulate tube voltages of least 46 kVp for the intended use (adult fingers/wrist/hands), above the 40 kVp limit of the device.

The device requires cooling fluid

This must be surprising to Nanox investors who are led to believe by the CEO that a cold-cathode tube, even if real, runs somehow cooler than a regular hot-cathode tube of the same power.

The intended use contradicts the disclosures in the SEC filings

Nanox implies in its SEC filings that the device will not be commercialized, and so the statement that the indented use is to perform diagnostic radiographic examinations is misleading.

Specifically,  Nanox states in its SEC filings:

the multiple-source Nanox.ARC [rather than this cleared Nanox.Cart device] ... will be our commercial imaging system (page 2, Prospectus). 

Nanox has further revealed that, while not intending commercial distribution of the cleared device, it is using the 510(k) submission as part of its regulatory strategy, a step in 

a multi-step approach to the regulatory clearance process (page 1, Prospectus), 

where the apparent ultimate goal is to induce the FDA to clear the "the multiple-source Nanox.ARC" device by first creating a predicate out of the Nanox.Cart.

Therefore, any statements by Nanox about "indications for use" or intended use or intent to market the cleared device, other than an admission that the device is not intended to be marketed and the submission is simply a step in Nanox regulatory strategy, are problematic.

Update:  Here is a cheap (dental) tube, Toshiba/Canon D-081B, that is used in other devices cleared under the IZL  product code, that is smaller but much more powerful and much more useful than the proposed "Nanox Tube."

Update:  Replaced "implied by 2mAs and 1 second" with "implied by 0.08kW power output and 40 kVp tube voltage" as it is the correct derivation for max tube current (sustained for 0.1s) - in this case, both derivations result in 2mA tube current.

Update:  Nanox predecessor claimed in 2016 that the chip that forms its cold cathode can do 2.5A/cm2 (Nanox CEO was a Chief Strategy Officer at the time).  If Nanox had made no improvements since, it means that the active area of its "chip" is now 0.0008 cm2 or a square of about 0.3 mm x 0.3mm.  So why do the chips shown in Nanox annual report (page 66) and in a March 2021 tweet look much larger, at least 10 mm x 10 mm?  Each covering an area that is at least 1000x the supposed area claimed in 2016 ...

 

Of course, as discussed elsewhere on this blog, Nanox has been unable to manufacture such a chip commercially (and so the proposed Nanox Tube is almost certainly not using any chip or any cold cathode), contrary to claims in its annual report (the University of Tokyo labs, which Nanox claims to rent, prohibit commercial use).

Update May 11, 2021:  Replaced the image of the wafer from the annual report with an image from a tweet that shows the chip next to a ruler.   

Update May 14,2021: Garage Blitz TV @Youtube makes a great point about the reference device using a CNT tube, which according to the Nanox annual report cannot work.  Moreover, the Nanox "founder" claimed in November 2019 that no such device exists, to the best of Nanox "knowledge."  

The curious case of Nanox.Arc's development

Last week @Ehlyz on Yahoo linked to a webpage of the engineering firm Ziv-Av and wrote:

If you are still worried this company is fraud and there is no end product to sell, take a look at who is building their CT scanner, Ziv-Av, who is also a vendor for Mazor Robotics and other medical companies.

Sure enough, the engineering firm Ziv-Av claims that the Nanox.Arc device was developed by Ziv-Av's engineers, not by Nanox (Nanox supposedly only contributed a proposed x-ray source).

According to the webpage, published sometime in 2020 prior to Nanox IPO, Nanox.Arc is a revolutionary x-ray device that could do anything the current technology could, but it is smaller, more mobile, and at least 1/100 as affordable.  The device was developed in record time - just 3 months, from scratch and for peanuts (Nanox shows in its prospectus on page 9 less than $3 million in research and development expenses for the entire 2019).  It was this working prototype that supposedly led to the equity raise and Foxconn "endorsement" in January 2020.

The problem is that that the device shown on the webpage (Nanox.Arc version 1.0, according to Nanox tech webpage) is completely fake.  It cannot take any x-ray images because it does not have any x-ray tubes and any x-ray detectors.  It only has a battery and blue LED lights - no need for the special cooling system that Ziv-Av claims to have developed.   

Ziv-Av's claim that this was a "working" prototype also contradicts the draft registration statement that Nanox did not have a working prototype prior to February 2020 (that is, the equity raise in January 2020 must have occurred without a working prototype):

We have not produced a working prototype of the Nanox.Arc (page 9) 

Moreover, if the working prototype looked like what Ziv-Av is showing, then the device in the demo to Foxconn in December 2019 shown below must have used a non-working prototype - that is, the demo was fake.

device demoed to Foxconn, December 2019

Here is the list of all the false and weird claims by Ziv-Av on that webpage:

1.  Ziv-Av develops revolutionary and affordable CT scanner for Nanox

Nope, even if the device were not fake, it cannot be used as a CT scanner due to limited number of projections (a CT scan uses hundreds of projections at different angles per arc/rotation).  It is affordable only because it is completely fake. 

2.  Nanox is a medical imaging company which has developed a revolutionary CT device that is mobile, substantially smaller and extremely cheaper than the existing devices. 

Nanox now denies that its proposed concept device is a CT device, and says it is a tomosynthesis device (unable to generate axial slices).  The device is cheap only because it is fake - the main cost of a real device would be in the detector.

3.  Nanox’s CT technology is based on digital X-ray production using a MEMS component instead of conventional flame lamps enabling cost reduction by orders of magnitude. 

There is no such thing as digital x-ray production - the proposed Nanox x-ray source generates x-rays the same way as a regular $100 hot-cathode x-ray tube - by smashing a bunch of electrons into a metal target.  And the cost of a Nanox tube will always be higher than a regular x-ray tube of the same performance, as any non-defective chip will cost more to make than a filament (a piece of wire).  It is also apparent that Ziv-Av believes x-rays are generated by conventional flame lamps - not clear whether burning kerosene or lamp oil.

conventional x-ray tube per Ziv-Av ( image source: https://www.freeimages.com/photo/the-oil-lamp-3-1535516 )

4.  The device supports scans such as CT, mammography, fluoroscopy and angiography.

Nanox now denies the CT and mammography "support" (CT-like imagining with 11 sources is now a simulation only).  Fluoroscopy and angiography are still on the table for the concept device, but they would be extremely limited, as its device lacks the positional flexibility of modern low-cost C-arm devices.

5.  Ziv-Av engineers revolutionized the medical imaging system 

Nope - the medical imaging system is still the same.

6.  Nanox approached Ziv-Av for the design of the revolutionary digital X-ray machine and its prototype within a stringent timeline of three months.

This may actually be true.  But the only revolutionary thing was the complete fakeness of the device. 

7.  Among many other design features, Ziv-Av designed the arch of the scanner which scans the patient’s body from different angles. 

Oh, so the Arc idea came from Ziv-Av rather than Nanox...

8.  The arch is designed to work with a very high voltage of 70,000V which creates immense heat. 

The statement that 70kV is associated with immense heat shows that Ziv-Av engineers do not understand basic physics and engineering.  An x-ray tube that operates at 1mA generates less heat than a 100W lightbulb.  Also, 70kV tube voltage is too low for a general x-ray device (it could be ok for extremities). 

this lightbulb generates immense heat per Ziv-Av (image source: https://www.freeimages.com/photo/light-bulb-1531205 ) 

9.  Ziv-Av managed the heat dissipation by designing a cooling system. 

The cooling system in the device is fake and not needed, as there is no x-ray source.  Subsequent proposed device iterations by Nanox show that the proposed "cooling system" is just a CNC-cut metal slab - a simple, and not very effective, heat sink.

 

10.  Along with the arch of this amazing machine, Ziv-Av also provided the design of the machine’s table, mechanics, electricity, electronics and motion control system .

Wow - so the only thing that Nanox has developed was the proposed x-ray source, and everything else (fake, of course) came from Ziv-Av? 

11.  Through its specialists, Ziv-Av achieved a significant cost-reduction – realizing Nanox’ vision of affordability to all.

True.  A fake device without an x-ray source or a detector or even a high-voltage generator would be cheap and affordable, indeed.  And, as a plus, it does not even require radiation shielding.  The only downside - it can generate no images.

12.  Ziv-Av excels in cost-effective prototype production.  Ziv-Av’s multidisciplinary engineers provided a turnkey solution from design to production of this innovative machine. 

It is innovative and cost-effective, as it is completely fake - a rarity!

12.  All the production, assembly & integration and tests were performed in Ziv-Av’s well-equipped workshop. 

No doubt.  Again, Nanox only contributed a proposed (fake) x-ray source.  

13.  The demonstrations of this perfectly working prototype helped Nanox raise $26 million within three months from many investors including ‘Foxconn-the IT industry giant’. 

By perfectly working, Ziv-Av means it can light up in blue using the built-in LEDs and a 12V battery, of course.

14.  From scratch to a revolutionary, cost-effective design as well as a working prototype – Ziv-Av accomplished all in just 3 months.

Nice.

What the webpage does not say is that the engineering firm's owner, Mr. Ziv-Av, at some point a chief scientist of the Israeli Ministry of Transportation, was convicted of securities fraud and then claimed that he did not know what he was doing.

Update:  Apparently, a Nanox promoter also tweeted about Ziv-Av last week, transforming CT or computed tomography into "3d tomo" (tomo simply means slice in greek), falsely claiming that a single (non-axial) slice meant CT-like capability, and insisting 70kV or less is not a problem for chest:

Chest/lung, musculoskeletal including skull likely on this 510(k) w/ enhanced 3D, slices, plus 2D x-ray. Cheap device. Will expand market.

Yeah, will expand the market with a completely fake device.

Update December 20, 2021:  Minor spelling correction.  

Another confirmation that Nanox.Arc is fake

Nanox tweets a short video today, confirming that Nanox.Arc is a non-functional fake "future product," rather than a real device in production.  So much for the 25 devices that were supposed to have already been made in March - they must have been all fake, too. 

 

Notice how the two assemblers just carry the arc with the empty tube housing and mount it on the device base.  No x-ray tubes means the device is non-functional and fake. 

The device also appears to lack a detector - the table is put directly over where the detector should have been.  Just another reason why the device cannot take any images and is fake.

But the two 12V batteries in the base below where the missing detector should have been may be real.

More later.

News in Nanox annual report

What's news and notable in Nanox annual report, relative to the Prospectus filed in February? 

Material weakness

We have identified a material weakness in our internal control over financial reporting in connection with the audit of our financial statements as of and for the years ended December 31, 2019 and 2020. (page 49)

Oops.  That's even before any revenues are recognized.

Dangling chips 

 As mentioned above, we currently manufacture the MEMs X-ray chips in the clean rooms located in Tokyo, Japan (page 15)

Nothing like it is mentioned above (in the annual report).  The rest of the statement, of course, is also false - the clean rooms located in Tokyo, Japan do not allow commercial use, and therefore Nanox cannot manufacture the proposed "digital" x-ray source that relies on those chips (and, in reality, there is nothing digital or MEMs about them).

 

No working Nanox.Arc

Although we have produced a working prototype of the Nanox.ARC and developed a prototype of the Nanox.CLOUD, we have not produced any of the approximately 15,000 Nanox.ARC units planned for the initial global deployment under the contract manufacturing agreement with FoxSemicon Integrated Technology, Inc., a subsidiary of Foxconn (“FITI”).  (page 7)

So, one working prototype of Nanox.CART, the one that got cleared?   But no working prototypes of Nanox.Arc?  Is this an admission, finally, that the RSNA 2020 demo of the Nanox.Arc was faked?  Why couldn't Nanox complete even one of the 10 prototypes that Nanox was supposedly assembling in November 2020 (according to the Q3 2020 results call)?  What happened to those mock-ups in all these production photos pushed by Nanox and its promoters this year?

A side note here:  Nanox never signed an agreement with FITI, according to the text of the contract manufacturing agreement.  The agreement was signed with a Japanese company that is not a Nanox subsidiary, according to public corporate records.

No ceramic tubes

We are evaluating, subject to completion of testing, a transition from glass-based X-ray tubes to ceramics-based tubes for cost efficiency purposes, which are the tubes to be used in the multi-source version of the Nanox.ARC, and we intend to enter into an agreement for such ceramics-based tubes with a new manufacturer in the future. (page 14)

That is, Nanox still cannot manufacture the ceramic tubes that the CEO claimed were used at the RSNA 2020 demo of both the Nanox.Cart and Nanox.Arc.  So, the RSNA 2020 demo was fake and the FDA 510(k) submission may have been fraudulent.

Fuji is out

We have not entered into any licensing agreements; however, we expect to enter into negotiations regarding a commercial arrangement with FUJIFILM Corporation for the licensing of our Nanox System. Any of the above factors may negatively affect the implementation of our Licensing Model, or cause our Licensing Model to fail. (page 12)

This is an admission that Fuji is not a Nanox Mamography OEM (that is, all Nanox investor presentations so far have been misleading ).  In the Prospectus, Nanox still falsely claimed:  

We are currently discussing the terms of a potential commercial agreement with FUJIFILM Corporation.

Chinese tubes 

We have, and expect to enter into, agreements with manufacturers and/or suppliers in China for the production of our X-ray tube, the Nanox.ARC and some of their respective components. (page 23)

Is this an admission that Nanox is using a regular low-cost, low-quality, hot-cathode Chinese x-ray tube and calling it "digital?"

 

A confused FDA: Cart or Arc

 

... we submitted a 510(k) premarket notification for the Nanox Cart X-Ray System... in January 2020... On January 30, 2021, we received additional information requests from the FDA which, among other things, require us to address certain deficiencies and questions, including requests that we provide additional support regarding the intended use of the Nanox.ARC and the comparability of the Nanox.ARC to the predicate device. We submitted our response to these requests on March 1, 2021. On April 1, 2021, we received clearance from the FDA to market our Nanox Cart X-Ray System. ...we may seek alternatives for commercialization of our Nanox Cart X-Ray System.  (page 32) 

Why was the FDA asking about Nanox.Arc in January 2021?  The device that got submitted and eventually got clearance is Nanox Cart X-Ray System, that is, the ugly Nanox.Cart, not the fake Nanox.Arc. The FDA should have asked about Nanox Cart X-Ray System, no?

Nanox also confirms that it still has no plans the market/commercialize the Nanox Cart X-Ray System even after its pre-market notification got cleared.

Update:  Muddy Waters tweets about Gilad Yron, the Chief Business Officer, no longer counting as an executive, which I missed (it is not clear what his current role is, if any). 

Update April 8, 2021:  Fixed some spelling.  Also, the Nanox.Cloud prototype developed by Nanox is just a collection of a few mock-up screens that use stolen images and contain non-sensical findings.  

Pumping while selling

 The CEO went on Bloomberg yesterday to pump the stock.  

He did not tell the audience that he put an order to sell 1,003,931 shares just hours earlier (at a low expected price of about $41).  The CFO sold only 40,533 shares.   Both selling according to a 10b5-1 selling plan supposedly adopted on March 4, 2021 (but that plan was not disclosed in the two prior 144 forms filed by the CEO)...  Nice.

There are some gems in the Bloomberg interview - more later.

Update April 7, 2021:  

Gem #1:  The tube the CEO is holding, while selling his shares, is fake, non-functional - it appears the vacuum sealing has failed (if there was ever one) - and cathode elements are falling off...

Gem #2:  5 tubes in Nanox.Arc, not 6.  The CEO insisted on 6 tubes in Nanox.Arc (and finalized design) at RSNA 2020. 

Gem #3:  The predicate device for Nanox.Cart is one of GE machines.  That indicates potentially fraudulent 510(k) submission, as all GE machines (that I am aware of) under the IZL product code can do Chest PA, the most common x-ray image done in the world, while Nanox.Cart, as demoed at RSNA 2020, can't.  The upcoming 510(k) summary should shed more clarity here.

Update December 12, 2021:  The interview is still available on Youtube.  The CART is not cleared for chest, only for hands, wrists, and fingers.

CT vs Tomo vs Fluoro

I have been having some interesting discussion with Nuno Lemos aka StockZombie @ Twitter, who has compiled his due diligence on Nanox at "Nanox Vision – a fools gold?"  

Here is some feedback on some of his points. 

Can you replicate CT with Tomo?

Nanox has been misleading the public, investors, and medical professionals for quite some time that it can do CT (including the "noise-free simulation" slide shown on the TV screen near the end of the RSNA 2020 presentation, 24:04).

That simulation was supposedly done with an imaginary device with 11 sources and detectors that don't exist.

But Nanox admits in its Prospectus that it intends to do only tomosynthesis - no usable axial slices can be produced.  CT or CAT is a short-cut for Computed Axial Tomography.  See also below.

Does the proposed Nanox.Arc 2.0 have 5 or 6 x-ray sources?

The information about the 5 x-ray sources comes from a video showing the making of Nanox.Arc 2.0.  If one pays close attention at 0:19-0:20, one can see the holes of the 5 sources.  I tweeted about it and so did Nanox promoter, but he did not count the holes.  

counted by me

not counted by promoter

The CEO was lying throughout the RSNA 2020 presentation that the device had 6 x-ray sources.  If the sources were so precious and novel, he would have gotten a least the number correct, as this was the first public demo of the source.

Here is how Nanox advertised its presentation on its exhibitor page at RSNA 2020:

Nano-X Imaging Ltd Nanox is a developer of MEMs based electrons field emitter cold-cathode, enabling the manufacturing of digitally controlled, low-cost x-ray tubes. Nanox's technology is under third party review, pending 510k clearance. Please join the Virtual Meeting Room button below at 10:30 am CST on Thursday, December 3 for a Featured Demonstration as Nanox unveils a proprietary digital X-ray source based on a silicon MEMs electrons field-emission technology. The presentation debuts a novel X-ray tube that emits digitally controlled X-ray pulses and can be used across multiple medical imaging use cases. https://www.nanox.vision 

So, what is the main proposed modality of Nanox.Arc 2.0?

Page 1 of the Prospectus explains that the main use of the Nanox.Arc that Nanox supposedly plans to commercialize is tomosynthesis:

Subject to receiving regulatory clearance, the first version of the Nanox.ARC that we expect to introduce to the market will be a three-dimensional (“3D”) tomosynthesis imaging system. Tomosynthesis is an imaging technique widely used for early detection, that is designed to produce a high-resolution, 3D X-ray image reconstruction of the scanned human body part for review by a professional diagnostics expert

Slide 8 from the March 17, 2021 Oppenheimer presentation states: 

The Nanox.ARC 3D computerized tomosynthesis:  New breed of medical imaging.  

Also, if one looks carefully during the RSNA 2020 presentation video (for example, at 12:55), what Nanox appears to be doing for any "scan" is collecting 45 images (5 sources x 9 tilted positions) and creating synthetic slices from them in a plane parallel to the flat detector placed in the "box" below the arc.

Can the proposed Nanox.Arc, either single-source or 2.0, do fluoro?

According to Nanox, Nanox.Arc can do fluoroscopy (even though it is not its main use case), but Nanox can also license its proposed x-ray source to traditional device manufacturers to incorporate in their own fluoroscopy systems (the white paper addresses that second case).  Today's fluoroscopy systems are very simple - a single source (pulsed, for two reasons - to prevent source overheating, and to reduce radiation exposure) and a fast detector (10+ fps) - clearly a single-source Nanox.Arc can do it (for say, $200,000/unit) ,assuming a powerful enough hot-cathode dental source with a stationary anode (but the best price quote for a new system I have gotten is $28,500/unit FOB Shanghai, and it is not cleared yet in the USA, so it cannot be used as a predicate).  

Slide 20 of the January 2020 presentation at JP Morgan shows the multi-source Nanox.Arc device doing "3D fluoroscopy" (I guess you need a Hololens or Oculus headset for it) using 3 of the 5 sources. 

Yes, fluoroscopy has its own product code(s) for 510K clearance purposes (for example, JAA), but a system can have more than one product code for clearance purposes.

Update:  Here is the completely-misleading slide from the January 2021 JP Morgan presentation that shows that the proposed Nanox.Arc 2.0 can replace the Chinese fluoroscopy system, among others.  See also my previous post, focusing on cost.

An early easter egg

Nanox removed the link to its Mammography white paper from its webpage sometime in January 2021 (the paper was first published in late November 2020 in the company's RSNA 2020 virtual booth, and then a link to it was posted on the front webpage in December 2020).  There must be something very important there for Nanox to remove it. 

Maybe it is this:

The first application for [Nanox novel x-ray source] technology is breast tomosynthesis using Nanox’s small X-ray sources in an arrayed series.

Proposed stationary array head (design concept)

Doesn't look much like the multi-source Nanox.Arc, which is supposed to be the first commercial device using the proposed Nanox source, does it?

The paper itself is self-contradictory.  It claims on page 14 that the scan time of one 3D image in present breast tomosynthesis is 15 seconds - moving tube between shots.  But on page 17, the paper admits that the gantry of the 10-year old Hologic machine takes only a total of 4 seconds for the scan (this old intro confirms it).

Why is this important?  Fujifilm, the first potential licensee for Nanox source (see page 88 and II-3 in this registration statement), declined to license the technology when its rights expired in June 2020, but Nanox insists that Fujifilm is still its strategic shareholder and a Mammography OEM (presentation slides 3 and 35 from JP Morgan conference in January 2021).  Nanox also told the press in March 2020 that its Nanox.Arc can perform no-squish mammography, which, of course, it can't (not even in theory):

It could perform tests such as ... a no-squish mammogram for women.

More later.

Update March 31, 2021:  Nanox promoters insist that Fujifilm invested in Nanox.  According to Nanox draft registration statement filings with the SEC, that is not really correct.  For example, the December 2019 filing states that in May 2019, Nanox Gibraltar (that is not Nanox, but its predecessor) issued 1,583,710 ordinary shares to FUJIFILM Corporation for an aggregate purchase price of approximately $3.5 million, and in exchange FUJIFILM was granted a right to first negotiation for license - a right that FUJIFILM declined to exercise and it expired.  A draft filed in August 2020 mentions the same number of shares, but the prospectuses filed in August 2020 and February 2021 do not mention any Fuji shares.  It is rather strange that the number of shares remained the same between December 2019 and August 2020, as a January 2020 press release by Nanox implied that Fujifilm participated in another funding round.

Foxconn is joining Fujifilm, SK Telecom, and other private investors, who have previously invested in the project, as part of a round that is aimed to support Nanox’s development, commercialization, and deployment of its Nanox System.

The press release, issued just before the supposed submission for FDA clearance, is also remarkable because it proves that the Nanox device (presumably, the multi-source one) cannot be cleared. 

The Nanox System is composed of the Nanox.Arc, a novel digital X-ray device...

Novel devices, by the dictionary definition, are obviously not substantially equivalent to any device on the market. 

Update April 12, 2021:  Nanox promoters continue to insist that Fujifilm invested in Nanox, citing a crunchbase entry about the Series B round.   However, it appears crunchbase simply misread the tricky Nanox press release.  

Foxconn is joining Fujifilm, SK Telecom, and other private investors, who have previously invested in the project, as part of a round that is aimed to support Nanox’s development, commercialization, and deployment of its Nanox System.

See, the press release never states that Fujifilm invested or is about to invest in Nanox.  It says that Fujifilm invested in "the project" (that is, Nanox Gibraltar, a Nanox predecessor).  And it does not say that Fujifilm is participating in this round.  In any case, all subsequent SEC filings confirm that Fujifilm did not invest in Nanox - either in that round or thereafter.  As confirmed by the recent annual report, Fujifilm is neither a strategic investor in Nanox nor a Mammography OEM for Nanox, contrary to all investor presentations. 

see, for example, page 3 and 35 in January 2021 presentation at JPM conf.