Somatics is the leading manufacturer of ECT equipment world-wide. Its Thymatron® is the most advanced hardware on the market today.

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Maximum Ultrabrief Response

Age-Based Stimulus Titration

EEG Seizure Intensity & Duration

Higher Stimulus Current

Greater Cerebral Stimulation

Best Seizure Generalization

Efficacy by Peak Heart Rate

RE: Jonathan Emord and Kendrick Moxon, Citizen Petition – Docket Number FDA-2016-P-2559

Dear Mr. Emord and Mr. Moxon:

"In your petition, you request that FDA ban ECT devices.   ...Your petition does not argue that ECT devices present any substantial deception. Moreover, as discussed above, FDA finds the information you submitted, as well as other information that we have reviewed, does not support a finding that ECT devices present an unreasonable and substantial risk of injury or illness.

"As we discussed above and in the preamble to the 2018 Final Order, FDA disagrees that ECT contributes to adverse health outcomes or is unsafe for use in treating patients when used appropriately and with the assistance of health care professionals. During review of the scientific evidence, FDA did not identify sufficient evidence to ban ECT. FDA determined that special controls, in combination with general controls, can mitigate the identified risks of ECT for certain class II intended uses and mitigate risks associated with ECT use. FDA determined that there is a reasonable assurance of safety and effectiveness for ECT treatment for the identified class II indications for use and patient populations.   ...Specifically, FDA has determined that the risks to health presented by class II ECT devices can be addressed through the general controls of the FD&C Act in conjunction with the special controls.   ...In sum, after a systematic review of the literature and public comments FDA received in response to its 2015 Proposed Order, FDA concluded that, based on all available data and information, and as discussed above, the ECT devices do not present a substantial and unreasonable risk of illness or injury for any of the intended uses identified in the 2018 Final Order. Accordingly, the statutory standard for a ban is not met and, regardless, FDA declines to initiate rulemaking to ban ECT. Therefore, your request that FDA initiate rulemaking to ban the use of ECT devices is denied.  ...During the discussion on January 28, 2011, the Panel discussed the information submitted by Mr. Moxon. The 2011 Panel specifically mentioned reading the information submitted by Mr. Moxon and concluding that it did not agree that the information was proof of brain damage as a potential risk."

Ellen J. Flannery, J.D.
Deputy Center Director for Policy Center for Devices and Radiological Health
US Food and Drug Administration

Somatics is pleased to provide psychiatric professionals with a free e-book Guide to Electroconvulsive Therapy (2014) by Conrad Swartz, Ph.D., M.D. Dr. Swartz wrote this e-book for psychiatrists administering ECT, those interested in the latest ECT methods, and psychiatry residents and ECT nurses.

"The most up-to-date and concise guide to this indispensable treatment available anywhere today." Richard Abrams, M.D.

This e-book covers administrative requirements, patient selection, pretreatment procedures and orders, ECT stimulus characteristics and treatment electrode placement, anesthesia, physiological monitoring, medical complications, methods to minimize cognitive side effects, and examination after the ECT course.

Individual copies of Dr. Swartz' e-book can be obtained by qualified professionals at no charge in printable electronic PDF format by sending an email request to with your name, degree, city, affiliated hospital name, and email address.

[Outside North America please direct your email request to Somatics' distributor for your country, found at]

Age-based dosing required 25% fewer ECTs for the same clinical improvement as seizure threshold titration (p<0.02), in prospective study of 79 patients (Aten et al., 2015). Moreover, post-ECT the Montgomery-Asberg Depression Scale averaged 9.5 for age-based and 11.6 for titration use, while MMSE scores averaged 28 for both. ECTs were given with a Thymatron® System IV and pulse widths of 0.25-0.5 msec. The investigators expected advantages for titration but instead found that "the importance of age...possibly individualized approach to seizure threshold."

In age-based dosing the %Energy dial was set to age for unilateral ECT and to half-age for bilateral ECT, per standard practice since Petrides et al (1996).

Age-based dosing at 0.5 msec (or indeed any particular pulsewidth) can be consistently accomplished only with a Thymatron® instrument. Others require increasing pulsewidth to increase dose in higher dose ranges. This impairs clinical results because pulsewidths above 0.5 msec are less effective and also provoke more cognitive side-effects.

Aten JJ, et al., Eur Arch Psy Clin Neurosci 2015 Mar 25 (Epub). Conducted without involvement of an ECT device company.

Petrides G et al., Conv Ther 1996;12:138

In clinically similar studies of ECT efficacy in Major Depression, remission was achieved in 87% with the Thymatron® instrument (CORE study, Petrides et al, 2001) but only 54% with the Mecta (Columbia group, Tew et al, 1999). Fully 60% more patients achieved remission with the Thymatron® than the Mecta. Moreover, ECT sessions per patient averaged 7.8 with the Thymatron® but a whopping 13 with the Mecta, presumably yielding markedly shorter hospital stays. Greater antidepressant efficacy of the Thymatron® reflects the fact that per millicoulomb its 900 mA stimulus has 142% the seizure-inducing potency of the Mecta’s 800 mA stimulus, and that its brief pulse is more efficient at high doses. Don't your patients deserve better and faster results?

If you are one of the many doctors who are increasingly using the Ultrabrief ECT stimulus in order to obtain the best clinical outcomes with the least cognitive disturbance, you will find the following both informative and useful.

Somatics introduced the first Ultrabrief stimulus in 2001, long before the competition followed suit. We knew the special advantages of this extra-slim pulsewidth could only be systematically obtained if it were administered throughout the entire dosage range, a feature that we incorporated into the Thymatron® System IV from the outset. In stark contrast to Mecta’s claims, its machine is unable to maintain this requisite consistency—with increasing dosage its stimulus gradually widens from 0.3 ms to 0.37 ms, representing a 24% increase in pulsewidth and a corresponding reduction in cognitive advantage just at the point in the dosage range that patients most require genuine Ultrabrief stimulation.

But there’s even more to this story: Effective dosing is crucial for the therapeutic potency of conventional ECT, and this is no less true for Ultrabrief therapy. The Thymatron® instrument’s 900 mA maximum stimulus has 1.42 times the seizure-inducing potency of the Mecta’s 800 mA maximum stimulus (Swartz, JECT 22:54, 2006) providing the Thymatron®’s Ultrabrief stimulus a significant therapeutic advantage as well. The Mecta’s reduced effective dose very likely accounts for the disappointing clinical results obtained by Loo et al (2007) with its briefest pulsewidth: their patients required significantly more treatments than those receiving conventional ECT.


Since the Thymatron® System IV was first introduced it has been continually improved and upgraded to meet the expressed clinical needs of its current and prospective users. Each upgrade is accomplished by a simple microchip replacement in which each new version includes all previous upgrades--the equivalent of having a new device each time. The date of each upgrade and what it accomplished is as follows.

6/99 Software made DOS-compatible

9/00 Real time EEG-ECG monitoring via PC screen; Data upload to Palm® computer

5/01 Diagnostic messages revised for auto EEG endpoint report

8/01 Ultrabrief program introduced to automatically select best frequency and duration at each ultrabrief dosage

5/02 Automatic data upload to PC replaces manual upload; Seizure Energy Index algorithm improved; Seizure Generalization Index retired; Impedance test signal increased to more efficient 800 Hz

11/02 Special Cortical Activity Measures introduced

2/03 Eliminated need for recalibration after chip upgrade

7/04 Algorithm improved and refined for Postictal Suppression Index; Treatment program made selectable via Percent Energy Dial; EEG gain made adjustable during recording

5/06 Percent Energy dial made fine-tunable (1% increments) up to 10%

7/06 Second Ultrabrief stimulus choice added

2011 Thymapad electrode current capacity increased for greater safety; 0.5 ms pulsewidth minimizes cognitive side-effects

2012 900 mA verified as most efficient and effective stimulus

The Thymatron® System IV is the World's Only ECT Instrument that Never Can Become Obsolete

These special EEG signal processing measures provide continuous monitoring of level of consciousness and cortical activity: 95% Spectral Edge Frequency, Relative Delta Power, and Median Frequency (Billard V et al, 1997: A comparison of spectral edge, delta power, and bispectral index as EEG measure of alfentanil, propofol, and midazolam drug effect; Hans P et al, 2001: Effect of nitrous oxide on the bispectral index and the 95% spectral edge frequency during propofol-fentanyl anaesthesia; Sakai T et al, 1999: Hypnotic endpoints vs. the bispectral index, 95% spectral edge frequency and median frequency during propofol infusion with or without fentanyl).

1. Mecta Spectrum's top stimulus dose is weak. Millicoulomb for millicoulomb the Thymatron® is 42% more effective at inducing seizures than the Mecta (Chanpattana 2001; Swartz 2006). The extra strength of the Thymatron® stimulus helps get effective treatments in older patients and towards the end of longer treatment courses.

2. Mecta's top stimulus dose uses a 1 ms or wider pulsewidth. This is far less efficient than the 0.5 ms pulsewidth of the standard Thymatron® stimulus (Swartz, 2000). If you choose Mecta's 0.5 ms pulsewidth you are limited to half the maximum dose, just 288 mC.

3. It is far too easy to make a mistake setting the Mecta stimulus. It has 4 separate knobs that each change stimulus dose. Because each additional knob doubles the chance of an unintended setting, the Mecta Spectrum's 4 knobs make errors 8 times more likely.

4. Are you sure which of the four Mecta knobs to turn to increase or decrease the stimulus dose, and in what order? Mecta's method for doing this is complex, contrived, hard to remember, and without scientific basis. Because just one knob adjusts stimulus dose on the Thymatron®, and a scientifically-based program automatically selects the best frequency and pulsewidth at each setting, you can always be sure of giving the best possible treatment at each dose.

According to a recent notice from Mecta Corporation, if your hospital owns a Mecta SR-1 (or SR-2, JR-1, JR-2) you are faced with the problem that you will no longer be able to get it checked or serviced by the manufacturer, and parts are not available. Is it medically prudent to continue using your old Mecta under these circumstances?

Somatics can help you solve this problem: On your request we will immediately ship you a Thymatron® System IV to use for 30 days at no cost, and give you a $500 allowance for your old SR-1 (SR-2, JR-1, JR-2) if your hospital purchases the Thymatron® System IV.

Call David Mirkovich at 1(800)642-6761 today to find out more about this offer.

This offer applies only to US/Canadian hospitals and may be withdrawn without notice at the discretion of Somatics

If you’re a dyed-in-the-wool Thymatron® DGx fan who’s been holding off on upgrading to a Thymatron® System IV because of apprehension over having to acquire new skills, we have good news: a simple click of the System IV’s FlexDial™ reproduces the standard stimulus of the Thymatron® DGx, allowing you to treat patients just as you’ve always done. (And you can monitor with just 1 or 2 channels, too!)

A recent study headed by a core member of the Special Committee on ECT of the UK's Royal College of Psychiatrists has concluded that EEG should be routinely monitored during ECT.

Using a Thymatron® ECT instrument Dr. Susan Benbow and colleagues (2003) measured EEG seizure threshold and duration during 95 courses of ECT in 67 patients and found that almost 20% of ECT courses included at least one prolonged seizure, defined as lasting longer than 120 s.

Most importantly, during 19 individual treatments without an observed motor seizure, EEG seizure duration varied from 16 to 123 s., demonstrating conclusively that observation of the motor seizure alone is inadequate for determining whether a cerebral seizure—even one that is prolonged—has occurred.

In their study, the authors relied on the EEG seizure endpoint as automatically determined by the Thymatron®, because not all the doctors administering ECT in the study were trained to interpret EEG recordings clinically.

The authors recommend that the Royal College of Psychiatrists’ ECT Guidelines should include a requirement for routine EEG monitoring in all UK ECT clinics.

For more than 40 years Professor Jan-Otto Ottosson of Sweden has recommended a unique method for administering ECT that uses the observation of a strong plantar flexion response as a guide to ECT stimulus adequacy. (In fact, he and his colleagues considered this method so important that they published versions in Swedish, Danish, and English: d’Elia, Ottosson, and Strömgren, 1982; 1982; 1983).

First introduced using the old partial sine-wave Siemens Konvulsator, Professor Ottosson’s method consists simply of setting stimulus duration to the maximum and then pressing and holding down the stimulus delivery button while observing the patient’s feet. When a pronounced and persistent plantar flexion response is observed, the stimulus button is then released, terminating stimulation. (In fact, although Siemens discontinued manufacture of the Konvulsator almost 20 years ago, some Scandinavian doctors still retain their old devices in order to be able to use this particular method.)

The good news is that the Thymatron® System IV can be used exactly as the old Konvulsator: Just set the Thymatron® to deliver its maximum stimulus duration of 8 seconds and then press the TREAT button while observing the patient’s feet. As soon as the desired degree of plantar flexion is observed, remove your finger from the TREAT button to terminate stimulation—achieving the same result as with the Konvulsator.

Moreover, the Thymatron® System IV also features an intermittent stimulus mode that is modeled after the intermittent stimulus of the Konvulsator, allowing Scandinavian doctors to essentially duplicate all of the Konvulsator’s perceived advantages while using the latest modern equipment (in fact, the Thymatron® is the only ECT device manufactured today that offers an intermittent stimulus mode).

Ende et al (2000) recently used proton magnetic resonance spectroscopic imaging to study hippocampal effects of ECT given with a Thymatron® instrument. In 17 patients receiving either unilateral or bilateral ECT (all of whom improved with treatment), no differences were found from 30 control subjects in hippocampal N-acetylaspartate signals, supporting numerous earlier studies failing to find evidence for central nervous system abnormalities after ECT (Abrams, 1997).

According to the MECTA’s Instruction Manual for the Spectrum 5000, a "stimulus adequacy" measure (pat. # 5,626,627) is available as a costly optional extra.

This measure ranges from 0-99%. MECTA claims that “higher numbers [are] associated with a greater likelihood of seizure adequacy”. But is this true?

Mecta admits that “The stimulus adequacy measure provides an estimation, for both unilateral and bilateral ECT, of the likelihood that the induced seizure differs from that associated with barely suprathreshold unilateral ECT (a type of ECT shown by Sackeim and colleagues to be subtherapeutic).”

Indeed. Sackeim and colleagues (1987) achieved only a 17% response rate to barely suprathreshold unilateral ECT, lower than response rates reported for sham ECT (Abrams, 1997). Thus, MECTA’s measure actually describes inadequacy: how much the seizure is better than no seizure at all.

Because higher numbers reflect only a lesser degree of seizure inadequacy, even a result of 99% would just mean that the seizure was 99% less inadequate than no seizure or a subtherapeutic seizure.

In marked contrast, the Postictal Suppression Index of Thymatron® instruments (US Pat. #5269302) truly reflects seizure adequacy. Petrides et al (2000) obtained an 85% remission rate in major depressives with a Thymatron®. The average Postictal Suppression Index for these remitters was 87%, significantly higher than for the 15% of patients who failed to achieve remission.

The authors concluded: “These data support that higher PSI values (more abrupt ending of ictal EEG) are correlated with better clinical outcome of ECT in depression. This putative marker of seizure generalization may be useful as an index of treatment adequacy.”

In a recent study of ECT-device seizure efficacy Krystal et al (2000) found they had to set their old Mecta SR-1 machine to the maximum dose in 15% of their patients in order to get a barely acceptable seizure, and even at this dose, the MECTA failed to produce adequate seizures 5% of the time.

If you were hoping to improve this poor performance by trading in your old SR-1 towards a new Spectrum you will certainly be disappointed. Krystal and Weiner (2001) repeated their study using a Spectrum and got even worse results than with their SR-1 despite the Spectrum's somewhat longer stimulus: 30% of patients now required the maximum dose and 10% failed to obtain adequate seizures.

You knew the MECTA SR-1 was discontinued several years ago, but did you know it was already long obsolete? If your hospital owns an SR-1 the most efficient stimulus you can deliver has a 2-second duration and 1 msec pulsewidth, and it’s just not good enough—here’s why.

The Washington University study of Isenberg et al (1996) illustrates this point decisively, because these authors actually compared the MECTA SR-1 with the Thymatron® DGx for efficiency in stimulus induction in a sample of 403 patients. They used the Thymatron® to deliver a 0.5 msec pulse for the longest possible duration (up to 8 sec), and the MECTA to deliver a 1 - 2 msec pulse for up to its 2-second maximum. It was no contest: 80% of patients receiving unilateral ECT with the Thymatron® had seizures with 50 mC or less, compared with only 37% of patients treated with the MECTA. For bilateral ECT, the results were even more dramatic: 100% of Thymatron®-treated patients seized at 100 mC or less (thresholds are higher with bilateral ECT), compared with only 29% of patients treated with the MECTA.

Striking confirmation of this result comes from a recent report that titrated seizure thresholds to bilateral ECT were significantly higher with the MECTA SR-1 than the Thymatron® DGx in 79% of patients studied, averaging 61% higher overall despite careful matching of stimuli and patient titration increments (Chanpattana, 2001). [See DOWNLOAD page for PDF file of article]

As these studies abundantly demonstrate, inefficient electrical stimuli require higher doses to produce seizures, and unfortunately, higher doses cause more memory and cognitive side-effects without enhancing therapeutic potency (Abrams, 2002). Moreover, because the MECTA SR-1 limits stimulus duration to a maximum of 2 seconds, doctors using it are forced to select the highly-inefficient 2 msec pulsewidth in order to deliver the higher dosages needed for elderly patients or to administer unilateral ECT in the recommended range of 6 times threshold (Sackeim et al, 2000).

Incredibly, the Mecta Spectrum is hardly any improvement over the SR-1: you still have to use a 1 or 2 msec pulsewidth to deliver the maximum dose.

The amply documented inefficiency of the MECTA SR-1 is doubtless also responsible for its recently reported failure to produce adequate seizures in 5 of every hundred patients treated, and for the necessity of employing the maximum dosage in 72 out of 471 patients (Krystal et al, 2000).

It was already suspected over a decade ago that longer stimuli and shorter pulsewidths were most effective for ECT, which is when Somatics first introduced the Thymatron® DGx with its 8-second maximum stimulus and 0.5 msec minimum pulsewidth. Since then, the greater efficacy of longer-duration and shorter-pulsewidth stimuli has been repeatedly confirmed (Swartz and Larson, 1989; Rasmussen et al, 1994; Isenberg et al, 1996; Devanand et al, 1998; Swartz and Manly, 2000; Chanpattana, 2001).

The fact is, Somatics Thymatron® instruments are the only ones capable of delivering a 0.5 ms or even an Ultrabrief stimulus over the entire standard dosage range. And, with the new Optimal Charge Rate programs, a single button press assures you of always automatically delivering the most efficient stimulus (Swartz, 1994) at any dose you select
Isn’t It Time To Upgrade To A Thymatron®?

The particular details of internal construction of several consumable and operator-replaceable parts of the Thymatron® ECT device are essential for its safe operation. The Thymatron® ECT device received CE certification with these specific parts. The specific replaceable parts listed below are provided by Somatics LLC through its distributors, and they are the only replaceable parts certified and suitable for use with the Thymatron® ECT device.

ECET-P------ECT Treatment cable (7 pin-plug)

Effective July 18, 2012 the date of expiry of Thymapad electrodes is two years from manufacture date. This unconditionally supersedes all previous statements.

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