The World of Implantable Devices – Page 31 – A blog about what is new (and old) in the world of active implantable medical devices

CardioMEMS Miniature Implantable Wireless Sensors

Posted on December 29, 2011 by David Prutchi Posted in Aneurysm, CardioMEMS, Heart Failure (CHF), Telemetry

CardioMEMS miniature implantable sensor for heart failure and aneurism management

CardioMEMS was founded by Dr. Jay S. Yadav and Dr. Mark G. Allen in Atlanta, GA in 2000 to develop implantable micro-electromechanical sensors to improve the management of severe chronic cardiovascular diseases such as heart failure and aneurysms.

The miniature wireless sensors can be delivered through a catheter. Once in place, they transmit cardiac output, blood pressure and heart rate data that are critical to the management of patients. Due to their small size, durability, and lack of wires and batteries, CardioMEMS’ sensors are designed to be permanently implanted into the cardiovascular system. An external reader is used to interrogate the sensors. Continue reading→

NDI Medical’s Miniature MicroPulse Neurostimulator

Posted on December 29, 2011 by David Prutchi Posted in Incontinence, Medtronic, Muscular Stimulation, NDI Medical, Pain, Paralysis, Spinal Cord Stimulation, SPR Therapeutics, Wireless Power Transmission

: Image Credit: SPR Therapeutics

NDI Medical was founded in 2002 by Geoffrey B. Thrope to develop and commercialize neurodevice products. NDI Medical developed the MicroPulse neurostimulator, a thumb-sized, rechargeable pulse generator, that has been used for the treatment of incontinence and pain, as well as an implantable device for the restoration of function of paralyzed limbs.

According to a 2006 news release by the electronics assembly manufacturer for the MicroPulse:

“Using minimally-invasive surgery, the Micropulse is implanted into a patient, usually in the lower abdomen or buttock, where the device is most comfortable and least visible. After implantation, a clinician uses a wireless programmer to set the Micropulse’s stimulus parameter and timing patterns. The programmer, as well as the patient’s controller for the device, has a range of about three feet.

To recharge the device’s lithium-ion battery, the patient applies a recharging patch for several hours to the vicinity of the implant. The battery needs recharging from once a month to every few weeks.” Continue reading→

Leptos Biomedical’s Splanchnic Nerve Stimulation For Treatment Of Obesity (2002-2010)

Posted on December 29, 2011 by David Prutchi Posted in EnteroMedics, Gastric Stimulation, History, Leptos Biomedical, Neural Stimulation, Obesity

Leptos Biomedical, Inc. Splanchnic nerve stimulation for treatment of obesity Leptos Biomedical was founded in Fridley, MN in 2002 by Dr. John D. Dobak. Leptos intended to develop an implantable device to stimulate the greater splanchnic nerve, that was hoped would result in reduced food intake and increased energy expenditure.

In February 2010 Leptos announced its closure. Reasons were not provided, but it has been suggested that the decision was prompted by the 2009 announcement by competitor EnteroMedics’ that it had failed to meet the primary goals of its pivotal study. EnteroMedics’ Maestro device didn’t perform any better than a sham device. EnteroMedics is now conducting a new study with the device.

Click here for Leptos Biomedical’s patents.

Palyon Medical’s Implantable Programmable Pain-Medicine Pump

Posted on December 29, 2011 by David Prutchi Posted in Drug Delivery, Pain, Palyon Medical

: Image Credit: Palyon Medical’s animation at www.biodigital.com

Palyon Medical Corporation was founded in 2004 in New York, NY, but recently moved its operations to Santa Clarita, CA. Palyon is still operating stealthily.

Palyon is developing a programmable implantable drug delivery system (IDDS) which delivers targeted doses of pain medication directly to the spinal area for the treatment of chronic pain, spasticity and other neurological diseases. According to Luis Malave, the company’s CEO, “Due to its inherent flexibility as a delivery platform, the IDDS can be used to deliver therapeutics to treat both acute diseases, such as cancer, and chronic diseases including diabetes and multiple sclerosis.” Continue reading→

Neuros Medical’s Implantable Device to Alleviate Amputation Pain

Posted on December 28, 2011 by David Prutchi Posted in Nerve Blocking, Neuros Medical, Pain

: Image Credit: Neuros Medical

Neuros Medical was founded by Jon J. Snyder in Cleveland, OH in 2008 to develop a neurostimulation therapy to alleviate chronic pain. The company’s Electrical Nerve Block™ technology is based on research done at Case Western Reserve University.

The company’s Nerve Block is an implantable device that delivers high-frequency stimulation to sensory nerves in the peripheral nervous system. Neuros’ aim is to stop a wide variety of chronic pain, including residual limb pain, chronic post surgical pain, and chronic migraine.

In November 2011 Neuros Medical announced that it has received IDE approval from the FDA to evaluate its technology for use in acute treatment of pain in the residual limb of amputees.

Company website: http://www.neurosmedical.com/

Click here for patents on Case Western University’s nerve blocking technology

Reliability Analysis of Active Implantable Medical Devices

Posted on December 28, 2011 by David Prutchi Posted in Reliability Analysis, Tech Talk

Relibility analysis bathtub curve We conduct reliability analyses for our implantable devices on a continued basis. I’ve spent the last few days readying the data for this period’s analysis, and thought that a short primer on how this is actually done would be of interest to fellow engineers who may need it at some point.

You surely have heard of MTBF = Mean Time Between Failures. This is a key reliability metric. However, since our implantable devices are single-use, the first failure is the final failure, so MTTF = Mean Time To Failure. As such, for a device with no possibility of repair (e.g. implantables, satellites), MTBF=MTTF. Continue reading→

NeuroVista’s Implantable EEG for Seizure Prediction

Posted on December 28, 2011 by David Prutchi Posted in EEG Monitoring, Epilepsy, NeuroVista, Telemetry

NeuroVista's implantable EEG for early epileptic seizure detection

Image Credit: NeuroVista

Seattle-based NeuroVista was founded in 2002 by Dr. Daniel DiLorenzo to develop an implantable device for the early detection of epileptic seizures.

The NeuroVista seizure advisory system is based on an implantable device that senses EEG irregularities that precede a seizure. Early warning allows patients to take medicine and find a safe place to lie down. Although some epilepsy sufferers can feel seizures coming, many cannot.

In NeuroVista’s Seizure Advisory System (SAS), intracranial EEG signals are recorded through electrodes implanted between the skull and the brain surface. Data storage and signal telemetry takes place within the pectorally-implanted can that transmits signals wirelessly to an external handheld device that processes the data and transmits visual and audible signals to the patient. The external pager-like receiver displays a blue light when there is a low likelihood of seizures, white indicates medium susceptibility, and red alerts to a high likelihood of impending seizure. Continue reading→

Radiation-Hardened ICs for Implantable Medical Devices

Posted on December 28, 2011 by David Prutchi Posted in Radiation Oncology, Ultra-Low-Power ICs

Radiation hardened integrated circuits for implantable medical devices

Lately I’ve received many inquiries about the paper on radiation-hardness testing of implantable integrated circuits that I published with Dr. Larry Stotts (now Executive VP R&D at Biotronik), and the late Dr. John Prince. This is because the effects of medical diagnostic and therapeutic radiation are becoming an issue of concern to physicians who often encounter the need for radiotherapy in the growing population of patients implanted with pacemakers, defibrillators, neural stimulators, and drug-delivery pumps.

Although the paper reported mainly on the test of floating-gate EEPROMs, the modern interest is on the test methods that we developed to test ICs used in implantable devices for hardness to the type of radiation encountered in the medical field.

Click here for our paper: D. Prutchi, J.L. Prince and L.J. Stotts, “X- and Gamma-Ray Hardness of Floating-Gate EEPROM Technology as Applied to Implantable Medical Devices”, IEEE Transactions on Electronic Components and Packaging Technology, 22(3), 390-398, 1999.

InControl’s Metrix Atrioverter (1990-1998)

Posted on December 27, 2011 by David Prutchi Posted in Atrial Flutter/Fib, Boston Scientific, Cardioversion/Defibrillation, Guidant, History, InControl

InControl Metric Atrioverter InControl was founded in 1990 in Redmond, WA to develop an implantable device for treating atrial fibrillation. In November 1995, InControl announced the first human implant of its Metrix atrioverter.

The implantable atrioverter system consisted of an implantable atrial defibrillator (model 3000 or 3020) connected to right atrial (perimeter right atrial model 7205) and coronary sinus (perimeter coronary sinus model 7109) defibrillation leads and a bipolar endocardial ventricular pacing lead, a programmer, and a defibrillation systems analyzer. The device had a volume of 53cc and weighed 79 g (model 3000) or 82 g (model 3020).

The device detected AF and delivers R-wave synchronous defibrillation shocks to convert AF to sinus rhythm. It was also able to pace the ventricle after shock delivery in case of bradycardia. Shocks could be delivered at a selected voltage up to 300V. The model 3000 defibrillator had an 80µF capacitor and could deliver a maximal shock of 3J with a biphasic waveform of 3 ms/3 ms. The model 3020 defibrillator had a 160-µF capacitor with a maximal shock of 6J with a biphasic waveform of 6 ms/6 ms. Continue reading→

Cactus/Freescale Semiconductor ICs for Implantable Medical Devices

Posted on December 27, 2011 by David Prutchi Posted in Ultra-Low-Power ICs

: Image Credit: Freescale Semiconductor, from “Integrated Circuits for Implantable Medical Devices”

An article by Steve Taranovich in the December 15, 2011 issue of EDN discussed technologies that are expected to be hot in 2012. One of these is the implantable chipset being developed by a collaborative effort between Cactus Semiconductor of Chandler, AZ and semiconductor giant Freescale.

SOCs developed by the alliance are expected to accelerate the development of innovative AIMDs. Continue reading→

Victhom Human Bionics’ Neurostep Implantable Closed-Loop Stimulator for Foot Drop

Posted on December 27, 2011 by David Prutchi Posted in Foot Drop, Muscular Stimulation, Victhom Human Bionics

: Image Credit: Victhom Human Bionics

Victhom Human Bionics was founded in 2002 in Saint-Augustin-de-Desmaures, Canada. The company’s Neurobionix business unit develops its implantable closed-loop system devices.

The Neurostep® is a neurostimulator designed to be implanted into the patient’s leg. Electrodes are attached to the peripheral nerves responsible for sensing and stimulating the muscles that lift the foot during normal walking. In operation, the device senses key physical events and stimulates the muscles of the ankle flexing the foot upward in patients suffering from foot drop.

Continue reading→

Spinal Modulation’s Neurostimulator for the Stimulation of the Dorsal Root Ganglion

Posted on December 27, 2011 by David Prutchi Posted in Mir A Imran (InCube), Pain, Spinal Cord Stimulation, Spinal Modulation

: Image Credit: Spinal Modulation

Spinal Modulation was founded by Mir Imran in Menlo Park, CA in 2004. The company has developed an implantable neurostimulator to deliver signals to the primary sensory neurons located within the dorsal root ganglion (DRG). The idea is that unlike dorsal column spinal cord stimulation, the Spinal Modulation system breaks the pain signal’s path before it enters the spinal cord. Continue reading→

Why Do So Many Novel Implantables Use a “Boxy” Enclosure?

Posted on December 27, 2011 by David Prutchi Posted in Enclosures, Greatbatch Medical (Power), Heraeus Medical Components, Hudson Technologies, National Manufacturing, Okay Industries

Deep drawn can for implantable medical devices

Active implantable medical devices are typically enclosed in a hermetically-sealed titanium housing which provides protection of the circuitry and other components.

Commonly, Grade 1 titanium is formed into the enclosure using stamping. The pretty, rounded shapes of modern pacemakers and ICDs are achieved by having two enclosure halves shallowly stamped from sheet stock material, and are then welded together to form the enclosure.

On the other hand, “boxy” enclosures that were popular in the 1970s are made by deeply drawing the titanium into a seamless can that is then capped by an ellipsoidal lid. However, many modern start-up companies still develop their early-generation implantable devices in this format because a number of off-the-shelf implantable-grade cells are available to fit in these deep-drawn enclosures, and the housings can be purchased off-the-shelf from various manufacturers. In addition, these enclosures provide sufficient volume for electronic assemblies manufactured using off-the-shelf packaged components and printed-circuit-board technology instead of more aggressive manufacturing methods (e.g. bare IC die on ceramic substrates) used by more established companies to miniaturize their mature implantable devices. Continue reading→

Nevro’s Senza Rechargeable Spinal Cord Stimulator for Back and Leg Pain

Posted on December 27, 2011 by David Prutchi Posted in Nevro, Pain, Spinal Cord Stimulation, Wireless Power Transmission

: Image Source: Nevro’s Website

Nevro Corporation (formerly NBI Development) was founded in 2006 by Dr. Konstantinos Alataris. The Menlo Park, CA company developed a pain management concept that originated at the Mayo Clinic into a spinal cord stimulation system for back and leg pain.

According to Nevro, their unique stimulation waveform achieves pain relief without paresthesia or uncomfortable stimulation. Few details are available about the waveform, but Nevro’s Spanish distributor’s brochure specifies it as high-frequency stimulation at 10,000 Hz. This is consistent with Nevro’s patent applications which teach that “high-frequency modulation in the range of from about 1.5 KHz to about 50 KHz may be applied to the patient’s spinal cord region to address low back pain without creating unwanted sensory and/or motor side affects.” Continue reading→

TransWorld’s Soul Mate Implantable Heart Transplant Rejection Monitor

Posted on December 26, 2011 by David Prutchi Posted in Telemetry, Transplant Rejection, TransWorld Heart

: Image Source: TransWorld Heart Corporation’s Website

TransWorld Heart Corporation of Charlotte, NC, was founded by Dr. Charles Richardson in 2004. The company developed an implantable device intended to replace routine post-transplant heart biopsies.

TransWorld’s Soul Mate implantable system analyzes 9 intramyocardial electrogram parameters recorded from 4 or 6 configurations of 2 or 3 epicardial leads to detect allograft rejection. Continue reading→