Dexmedetomidine- A New Short Term Sedative?

Interesting Review on "Dexmedetomidine", the most recent sedative approved by the FDA.

Dexmedetomidine: a novel sedative-analgesic agent Ralph Gertler, MD,1 H. Cleighton Brown, MD,1 Donald H. Mitchell, MD,1 and Erin N. Silvius, MD1 1From the Department of Anesthesiology and Pain Management, Baylor University Medical Center, Dallas, Texas; and Department of Anesthesiology and Pain Management, The University of Texas Southwestern Medical Center at Dallas. Corresponding author. Corresponding author: Ralph Gertler, MD, Department of Anesthesiology and Pain Management, Baylor University Medical Center, 3500 Gaston Avenue, Dallas, Texas 75246 (e-mail: Ralph_Gertler10@excite.com). Since the first report of clonidine, an α2-adrenoceptor agonist, the indications for this class of drugs have continued to expand. In December 1999, dexmedetomidine was approved as the most recent agent in this group and was introduced into clinical practice as a short-term sedative (<24 style="font-size: 0.8em; line-height: 0.8em; white-space: nowrap; ">2-Adrenoceptor agonists have several beneficial actions during the perioperative period. They decrease sympathetic tone, with attenuation of the neuroendocrine and hemodynamic responses to anesthesia and surgery; reduce anesthetic and opioid requirements; and cause sedation and analgesia. They allow psychomotoric function to be preserved while letting the patient rest comfortably. With this combination of effects, α2-adrenoceptor agonists may offer benefits in the prophylaxis and adjuvant treatment of perioperative myocardial ischemia. Furthermore, their role in pain management and regional anesthesia is expanding. Side effects consist of mild to moderate cardiovascular depression, with slight decreases in blood pressure and heart rate. The development of new, more selective α2-adrenoceptor agonists with improved side effect profiles may provide a new concept for the administration of perioperative anesthesia and analgesia. This review aims to give background information to improve understanding of the properties and applications of the novel α2-adrenoceptor agonist, dexmedetomidine.

Neuromonitoring & Peadiatric Cardiopulmonary bypass surgical procedures?:- Boosts Evidence Based practice & Best Practice?

Usage of intraoperative neurophysiologic monitoring during Peadiatric cardiopulmonary bypass surgical procedures reported in the following research papers, addition of IONM tothe surgical team has helped them to improve the post surgical neurological complications. Two of the following studies one published recently in Sept-Oct 2008 and the other in 2007, both in peer reveiwed journals discuss the importance of IONM usage in terms of reducing neurological risk, patient safety and faster discharge of patients that could be benefitial to both the patients and the hospitals.

The influence of neurophysiologic monitoring on the management of pediatric cardiopulmonary bypass.

ASAIO J. 2008 Sep-Oct;54(5):467-9

Kimatian SJ, Saliba KJ, Soler X, Valentine EA, Coleman ML, Kunselman AR, Schuler HG, Barnes ML,Thirumala PD, Myers JL.

Department of Anesthesiology, Penn State College of Medicine, Hershey, Pennsylvania 17033, USA. skimatian@hmc.psu.edu

We describe a process by which we sought to determine how the addition of intraoperative neurophysiologic monitoring (IONM) impacted the management of cardiopulmonary bypass (CPB) during pediatric cardiac surgery.

While maintaining a consistent team of surgeons, anesthesiologists, nurses, and perfusionists, a multi-modal, IONM program was established consisting of Near Infrared Spectroscopy, Transcranial Doppler, and eight channel electroencephalography. A retrospective review of cases from 1 year before the institution of the IONM program was compared with data obtained from cases performed after neurophysiologic monitoring was established as a standard of care for pediatric patients on CPB.

This comparative analysis of CPB management revealed a significant increase in the use of donor blood added to the CPB circuit prime as well as in the maintenance of a higher hematocrit during the bypass period after the implementation of IONM.

These changes in the management of pediatric CPB correlated with recommendations of previous studies that examined postoperative neurophysiologic outcomes, suggesting that these changes were not only consistent with best practices, but that the presence of IONM data facilitated a transition to evidence-based practice.

Benefit of neurophysiologic monitoring for pediatric cardiac surgery.

Austin EH 3rd, Edmonds HL Jr, Auden SM, Seremet V, Niznik G, Sehic A, Sowell MK, Cheppo CD, Corlett KM.

Department of Surgery, University of Louisville School of Medicine, Ky., USA.

BACKGROUND: Pediatric patients undergoing repair of congenital cardiac abnormalities have a significant risk of an adverse neurologic event. Therefore this retrospective cohort study examined the

potential benefit of interventions based on intraoperative neurophysiologic monitoring in decreasing both postoperative neurologic sequelae and length of hospital stay as a cost proxy.

METHODS: With informed parental consent approved by the institutional review board,

electroencephalography, transcranial Doppler ultrasonic measurement of middle cerebral artery blood flow velocity, and transcranial near-infrared cerebral oximetry were monitored in 250 patients.

An interventional algorithm was used to detect and correct specific deficiencies in cerebral perfusion or oxygenation or to increase cerebral tolerance to ischemia or hypoxia. RESULTS: Noteworthy changes in brain perfusion or metabolism were observed in 176 of 250 (70%) patients. Intervention that altered patient management was initially deemed appropriate in 130 of 176 (74%) patients with neurophysiologic changes.

Obvious neurologic sequelae (i.e., seizure, movement, vision or speech disorder) occurred in five of 74 (7%) patients without noteworthy change, seven of 130 (6%) patients with intervention, and 12 of 46 (26%) patients without intervention (p = 0.001). Survivors' median length of stay was 6 days in the no-change and intervention groups but 9 days in the no-intervention group. In addition, the percentage of patients in the no-intervention group discharged from the hospital within 1 week (32%) was significantly less than that in either the intervention (51%, p = 0.05) or no-change (58%, p = 0.01) groups.

On the basis of an estimated hospital neurologic complication cost of $1500 per day, break-even analysis justified a hospital expenditure for neurophysiologic monitoring of $2142 per case. CONCLUSIONS:

Interventions based on neurophysiologic monitoring appear to decrease the incidence of postoperative neurologic sequelae and reduce the length of stay. Inasmuch as the break-even cost for neurophysiologic monitoring is more than four times the actual average charge, both patients and hospital may profit from this service.

Because this study was not a truly randomized clinical trial, unintentional statistical bias may have occurred and caution is urged in interpreting the magnitude of apparent intergroup outcome differences.

Detached Skull But Intact Spinal Cord: Massive Accident with damages to Nervous System, 9 Y Boy Survives!!!

Pic from The MedGuru.com

Though Neurophysiological Details are not available, no Cranial Nerve restoration details are available in news reports, it is not clear how much of spinal cord functionally spared by the accident, how much motor and sensory functions of the boy was lost and recovered following the procedure is not clear. Despite the details are not out there on the news, surgical team and hospital certainly will have detailed information, the survival of this young Boy is unique, special and a medical achievement. 

A 9 year old boy after a fatal accident who was determined to have only 2% chance of survival is making great recovery after neurosurgical procedures?. 

This is a rare fatal accident almost sounds like a movie story but a real event happened in Hillsboro Texas, it is just amazing to realize a orthopedic decapitation is possible for a surgeon to work and fix the head and nerves back to functioning condition, though details are not available, but even considering this at a news level, it is nothing but Amazing. This is also the medical and surgical achievement of the surgeon and the crew.

Catharine Paddock, PhD writes at the Medical News Today, about a nearly decapitated 9 year old dcapitated boy was operated by Dr Richard Roberts, a pediatric neurosurgeon at the Cook Childrens' Medical Center in Fort Worth, as per the news below, the surgeon was able to fix the head back and the boy is recovering?. It will be interesting to know about how the facial and other Cranial nerves were placed back, if at all?. If all the Cranial nerves have damages or completely severed, how did the surgical team managed to keep the vital functions going?. 

Nearly Decapitated 9-Year Old Car Crash Boy Recovers

Jordan Taylor, a nine year old boy from Hillsboro, Texas, is making a rare and astonishing recovery from surgery to reattach his head to his neck after suffering an orthopedic decapitation three months ago; the youngster was buckled in the back seat of a car his mother was driving when they were hit by a dump truck that the authorities say ran a stop sign.

'Internal Decapitation': Boy's amazing recovery

Tuesday, December 23, 2008 | 1:42 PM

Surviving an 'Internal Decapitation'

Doctors quickly pointed out that an atlanto-occipital dislocation cannot be called a "decapitation" in the traditional sense. For one thing, even though the skull is disjoined form the spinal column, the head does not technically leave the body. And in Jordan's case, as with others, the spinal cord -- that crucial superhighway of nerve fibers that connects the brain to the rest of the body -- was not severed.

Still, Dr. Phillip Tibbs, chair of neurosurgery at the University of Kentucky, says that in many cases, the end result is much the same.

Health and Wellness News

Texas Boy Survives Orthopedic Decapitation

Atlanta, GA 12/22/2008 05:41 PM GMT (TransWorldNews)

A 9-year-old Hillsboro, Texas boy’s recovery from a near decapitation is being called a miracle. Jordan Taylor only had a 1-2 percent chance to live after suffering an orthopedic decapitation in a car accident 3 months again.

Jordan was riding in the back seat of a car his mother Stacey Perez was driving when a dump truck ran a stop sign and hit the vehicle. The boy’s skull separated from his neck but his spinal cord remained intact.

“The energy basically made his head lift up off his neck, and then move forward. All of the connective tissue that essentially keeps your head connected to your neck was destroyed,” says Dr. Richard Roberts, the pediatric neurosurgeon who operated on Jordan.

Jordan’s skull and neck has been reattached with a metal plate and titanium rods. Dr. Roberts says it’s a miracle that Jordan is able to walk and talk.

Click here for more People News

9 year old boy miraculously survives car crash decapitation

Texas, United States, December 23: A 9 year old boy from Texas was involved in a motor vehicle accident that separated his skull from his vertebrae three months ago, but doctors miraculously reattached his head to his neck and now he’s fully recovered.

According to his mother he’s planning to go back to school after Christmas break.

Neurophysiology News!

Neurophysiolgy & Pudental Nerve Connection:-

Beyond the Abstract - Evaluation of the Safety and Efficacy of ... UroToday - Berkeley,CA,USA Neurophysiological studies give invaluable information on the involvement of the parts of the nervous system which are essential in the control of sexual ... See all stories on this topic

Neuroscience Boot Camp ScienceBlogs - USA Laboratory visits will include a trip to an MRI scanner, an EEG/ERP lab, an animal neurophysiologylab, and a transcranial magnetic stimulation lab. ... See all stories on this topic

PEOPLE IN BUSINESS Delmarva Now - Salisbury,MD,USA She completed a clinical fellowship in neurophysiology at Henry Ford. In addition to her training in general neurology care, including headache and migraine ... See all stories on this topic

Medical Acupuncture Gaining Acceptance by the US Air Force MarketWatch - USA Based on modern neurophysiological concepts, Niemtzow developed a variation of acupuncture that involves inserting very tiny semi-permanent needles into ... See all stories on this topic

Novel method of chaotic communication proposed by physicists eTaiwan News - Taiwan In addition to use in communications, Hu went on, temporal transfer entropy can also be applied to many different scientific fields, such as neurophysiology ... See all stories on this topic

Blackrock can build bigger ICU Irish Medical Times - Dublin,Ireland The building to be knocked down contains a pharmacy, neurophysiology services and a prayer room. The current unit will also be revamped as part of the ... See all stories on this topic

Get lost ... and get better architecture MSNBC - USA ... before a single brick is ever laid, said Edelstein, a trained neurophysiologist and a visiting scholar at the University of California at San Diego. ... See all stories on this topic

IBIA-Brain Injury Conference?

 

NEWS

An Invitation to Washington D.C. As Chairperson and President of the IBIA 8th World Congress on Brain Injury to be held March 10 - 14, 2010 in Washington, D.C., USA, we would like to invite the participation of all professionals involved with serving persons with acquired brain injury to this international Congress and meeting of minds. We are very excited about having the meeting in the United States and in particular, its capital, Washington, D.C.  This is the first time in our history that a World Congress has been held in the USA.  Washington, D.C. is a culturally diverse city with many fine hotels, restaurants, museums, culture events and historical landmarks.  The meeting is expected to be the largest IBIA meeting in our history and in many ways the most exciting.  We hope that you will join us for this unprecedented event.

Transient Loss of TcMEP during L5-S1 posterior fusion?

In the following case report, a posterior lower lumbar surgical procedure done on a Spondylolisthesis (L5/S1) patient resulted in a transient loss of motor evoked potentials despite the patient had no neurological injury?. The motor loss was occurred after epidural injection of 2.4mg of morphine?. The authors believe it could be due to the pressure caused by the injection would have compressed cauda equina?.

Even a small injection of this kind could lead to evoked potential changes should be noted. Though the TcMEP recovered after 1h, care  must be taken to make sure prolonged compression does not take place!.

Case report

Transient loss of motor-evoked responses associated with caudal injection of morphine in a patient with spondylolisthesis undergoing spinal fusion

PETER R.J. GIBSON MBBS FANZCA*, Pediatric Anesthesia, Volume 16 Issue 5, Pages 568 - 572, 2005

A 7-year-old girl having posterior spinal fusion for Grade 3 anterior spondylolisthesis at the L5/S1 level was administered 2.5 mg of morphine in 10 ml saline via the caudal epidural route before surgery.

Motor-evoked responses were markedly diminished in her lower limbs for 1 h following this but returned spontaneously. She suffered no neurological injury. The cause for this is postulated to be transient cauda equina compression from the volume of injectate. This complication of caudal injection has not been reported before. The possible mechanisms for this are discussed. We believe that significant L5/S1 spondylolisthesis should be considered a contraindication to the use of caudal epidural injections.

Wave P300 (ERP) & Temporal Lobe Epilepsey

In this latest issue of the journal of Human Brain Mapping, the authors suggest that wave P300 an endogenous event related evoked potential seems to be altered in pateints with temporal lobe epilepsy, a change in the latency and amplitude of P300 was observed in 10 patients suffering from TLE (same number of normal recording was conduted for comparison). 

Hum Brain Mapp. 2008 Nov 25. [Epub ahead of print] 

Attention impairment in temporal lobe epilepsy: A neurophysiological approach via analysis of the P300 wave.

Bocquillon P, Dujardin K, Betrouni N, Phalempin V, Houdayer E, Bourriez JL, Derambure P, Szurhaj W.
Department of Clinical Neurophysiology, Lille University Medical Center, Lille, France.
Purpose:

Attention is often impaired in temporal lobe epilepsy (TLE). The P300 wave (an endogenous, event-related potential) is a correlate of attention which is usually recorded during an "oddball paradigm," where the subject is instructed to detect an infrequent target stimulus presented amongst frequent, standard stimuli.

Modifications of the P300 wave's latency and amplitude in TLE have been suggested, but it is still not known whether the source regions also differ. Our hypothesis was that temporal lobe dysfunction would modify the P3 source regions in TLE patients. Methods: A comparative, high density, 128-channel electroencephalographic analysis of the characteristics of P300 (P3b latency and amplitude) was performed in 10 TLE patients and 10 healthy controls during auditory and visual oddball paradigms. The P3b sources were localized on individual 3D MR images using the LORETA method and intergroup statistical comparisons were performed using SPM2(R) software. Results: Our main results (in both individual analyses and intergroup comparisons) revealed a reduction in temporal (and more particularly mesiotemporal) sources and, to a lesser extent, frontal sources in TLE patients, compared with controls. Discussion: This reduction may reflect direct, local cortical dysfunction caused by the epileptic focus or more complex interference between epileptic networks and normal attentional pathways. Hum Brain Mapp, 2009. (c) 2008 Wiley-Liss, Inc.

PMID: 19034898 [PubMed - as supplied by publisher]

BMP in Back surgery?:- What and Who?

Bone Morphogenic protein (BMP) is used in certain surgical procedures that involves lower lumbar surgery, but not in other procedures why?. Is BMP good compared to patients own bone transplantation or bone marrow substitute?. Right now it seems lime the FDA has approved BMP to be used only in lower lumbar cases such as L5-S1 procedures?. But, if BMP has anything to do with neurophysiological signals, not sure if there are any reports?.

Brain writes in this column about BMP, it's present usages and more...!. The full article can be read from his original site spine universe, click the topic for the link. 

BMP: The What and the Who

Brian R. Subach, MD, FACS
Neurosurgeon/Spine Surgeon
Virginia Spine Institute
Reston, VA

The title of this article asks two completely different but equally important questions. First, the "what." RhBMP-2 (recombinant bone morphogenetic protein, BMP) is a genetically engineered protein which both recruits bone forming cells to the surgical area and "turns on" local cells to the bone-making process. BMP is used for conditions requiring spinal fusion and stimulation of bone growth.

ABRET changes the Eligibility Requirement for All Exams?

ABRET has announced a major change in the eligibility requirement for exams like CNIM, Long Term Monitoring, EEG and EP technologists.  These news changes will be effective for some exams from Jan 2009 and for others from 2012. The change will apply to all the exams conducted by ABRET.  

The new requirements for CNIM exam is the candidate should undergo prior EEG credentialing???

There are two major requirements, of which the second one is already known to the folks in this area, but the first requirement:

1.An electroneurodiagnostic credential; R. EEG T. or R. EP T. or Canadian equivalent. A copy of current registration must accompany the Application.

For someone with a graduate degree or PhD or MD, if they wanted to be neuromonitoring specialist, they must undergo EEG or EP credentialing through ABRET?, does this makes any sense to those advanced degree holders?. It simply sounds to be ridiculous that ABRET is bent on making such changes as this would drive the PhDs and other advanced degree holders, there are already lots of shortage in neuromonitoring, it is difficult for companies to hire graduates with specialization in neurophysiology or neuroscience, with this new requirements, it is going to get worst to find someone with a credentialing in EEG or EP. 

As of January 1, 2010 the following eligibility requirements will be in effect for the CNIM Examination

The Certification Examination in Neurophysiologic Intraoperative Monitoring is designed and written for the advanced level electroneurodiagnostic professional who is currently practicing in an intraoperative environment.

All candidates must meet the following requirements by the application deadline. There are no alternative routes.

1. An electroneurodiagnostic credential; R. EEG T. or R. EP T. or Canadian equivalent. A copy of current registration must accompany the Application.

Disposable Surgical Face Masks: A Systematic Review

Here is an review on Surgical Masks, a careful review on Masks that looks at all the studies done so far and compares the various usage and it's safety.

Disposable Surgical Face Masks:

A Systematic Review

DISPOSABLE SURGICAL FACE MASKS: A SYSTEMATIC REVIEW

Authors: Allyson Lipp RN DipN RNT MA MSc, Principal Lecturer, School of Care
Sciences, University of Glamorgan, UK.
Peggy Edwards RN Dip Operating
Practice BSc Professional Practice, Welsh Risk Pool Assessor, Pontypridd,
UK
Acknowledgements: Cochrane Collaboration Wounds Group and the Theatre
Nursing Trust Fund. Extracts of systematic review reproduced by kind permission
of: Update Software, Oxford.

ABSTRACT

Surgical face masks were originally developed to contain and
filter droplets of microorganisms expelled from the mouth and nasopharynx of
healthcare workers during surgery, thereby providing protection for the
patient.

However, there are several ways in which surgical face masks could potentially contribute to contamination of the surgical wound. Surgical face masks have recently been advocated as a protective barrier between the surgical team and the patient, but the role of the surgical face mask as an effective measure in preventing surgical wound infections is questionable.
The aim of the systematic review is to identify and review all randomised controlled trials evaluating disposable surgical face masks worn by the surgical team during clean surgery to prevent postoperative surgical wound infection.

First Spinal Cord Endoscope Surgery Conducted in Iran

Can you imagine in this 21st century with so much of medical knowledge and medical care a first spinal endoscope surgical procedure is done on Oct 14, 2008?. A first spinal surgery in Iran, wow....finaly a surgical procedure to help patients with back or spinal problems is introduced in Iran by an American spine surgeon?.

Iran News Page One > Iran News First Spinal Cord Endoscope Surgery Conducted in Iran Oct 15, 2008 Iranian.ws The first spinal cord endoscope surgery was conducted in Iran, yesterday morning, by Professor John Chio, head of California Vertebrarium Research Center. Shedding light on details of such a surgery, Chio said: “During this surgery the tissues are not cut and the muscles are placed aside with highly delicate tools in order to reach the spinal cord and to lower disc pressure. Meanwhile, in order to stitch the wound, laser is used.” He added that in this surgery the patient does not bleed and therefore blood transfusion does not take place. The surgeon further underlined that the patient can leave three hours after surgery, resuming his social life within six days and commencing his athletic activities within three weeks. “The operation is also economically justified,” he added. He further said that one of his main goals is to train Iranian physicians, stressing that Iranian physicians are intelligent and can easily learn this operation.

Neuromonitoring:-Failing to be Assertive to communicate the neurophysiological abnormalities will cost you a Lot?

   Josh Colemna's back surgery went wrong during surgical procedure that involved possibly a scoliosis correction or posterior spinal correction, though the exact procedure done and details are not available, it is important to notice the role of neuromonitoring, fialing to do the right thing at right time will not only cost money, job but also someone's life.  
Neuromonitoring companies must make sure they have the competent neurophysiologists with a PhD or MD, or a neurologist is overlooking the technicians or else pay for the mistake. But, a neurophysiologist or neurologist will be able to warn the surgeon and anesthesiologist providing feed back instantly. Why it is so important to have this highly qualified professionals for doing some technical job is that they have the expert knowledge to troubleshoot as well as identify the causes of any changes if takes place, compared to a technician, he/she might be able to perform the technique but will have hard time in interpreting and convince the surgeon of a danger of injury to sensory, motor pathways or spinal cord injuries during back surgery. Anyways, this is an example of how much it will cost and how it will cost you if you fail to alert timely?.

March 24th, 2007 at 9:51 am

$11.7 M verdict against bystander doctor

» by Ted Frank

March 24th, 2007 at 9:51 am

$11.7 M verdict against bystander doctor

» by Ted Frank

A team of doctors at North Fulton Medical Center worked on Josh Coleman’s back surgery in 2003. Dr. Frank Puhalovich had a minor role: “he was only in the operating room for about 10 minutes making sure a technician properly hooked up a monitor that tracks nerve impulses along the spinal [cord] through electrodes attached to Coleman’s head and feet.” But after Puhalovich left, during surgery, the alarm went off: attorneys blame the surgeons’ failure to respond to the alarm in a timely fashion for Coleman’s paralysis. Coleman sued everyone involved, and all the doctors settled, except Puhalovich. So Coleman proceeded to trial against Puhalovich, blamed him also, and a jury awarded $11.7 million. The press coverage gives no indication what the theory of liability is against Puhalovich.

Joshua Coleman, sitting in a wheelchair next to his attorneys, Bill Stone and David Boone, smiled as the verdict was announced after the two-week civil trial.

“Josh is high as a kite right now,” Stone said. “He’s going to have a great weekend.”

(Beth Warren, “Paralyzed man awarded $11.7 million”, Atlanta Journal-Constitution,Mar. 24).

Update: Kevin, MD post with clever title Shotgun yields a jackpot.

 SATURDAY, MARCH 24, 20078

Shotgun yields a jackpot

A neurologist loses a verdict in a back surgery case. He was in the OR for less than 10 minutes, and didn't even operate on the patient. He got caught in the crossfire of a shotgun lawsuit. An unfortunate outcome, but the wrong doctor was targeted.

Cochlear Microphonics & CNAP recording in Neuromonitoring??

Anatomy of Ear (pic fromHearing and Hair Cells John S. Oghalai, M.D.Baylor College of Medicine ) (human ear pic: Muni's_neuromonitoring1)Jorge Bohorquez et al describes a system in their recent publication listed below, according to their study one can test both outer hair cell and inner hair cell electrical activity during surgical procedures. Though this work is evaluated in aniamal study, it is pretty interesting if this can be moved to the OR in our neuromonitoring procedures. I am not sure if this is already practiced in the OR by any neuromonitoring companies. It is a very common procedure to do auditory brain stem evoked potentials in tumor resection or craniotomy procedure that might put the 8th nerve in risk, nevertheless, this CM, CAP and CNAP will be a very important approach in certain cases where injury to both IHC and OHCs can be avoided?. 

Neuromonitoring of cochlea and auditory nerve with multiple extracted parameters during induced hypoxia and nerve manipulation

Jorge Bohórquez et al 2005 J. Neural Eng. 2 1-10   doi: 10.1088/1741-2560/2/2/001

Abstract.  A system capable of comprehensive and detailed monitoring of the cochlea and the auditory nerve during intraoperative surgery was developed. Jorge Bohórquez et al 2005 J. Neural Eng. 2 1-10 E-mail: jbohorquez@miami.edu

The cochlear blood flow (CBF) and the

electrocochleogram (ECochGm) were recorded at the round window (RW) niche using a specially designed otic probe.

The ECochGm was further processed to obtain cochlear microphonics (CM) and compound action potentials (CAP). The amplitude and phase of the CM were used to quantify the activity of outer hair cells (OHC); CAP amplitude and latency were used to describe the auditory nerve and the synaptic activity of the inner hair cells (IHC). In addition, concurrent monitoring with

a second electrophysiological channel was achieved by recording compound nerve action potential (CNAP)

obtained directly from the auditory nerve. Stimulation paradigms, instrumentation and signal processing methods were developed to extract and differentiate the activity of the OHC and the IHC in response to three different frequencies. Narrow band acoustical stimuli elicited CM signals indicating mainly nonlinear operation of the mechano-electrical transduction of the OHCs. Special envelope detectors were developed and applied to the ECochGm to extract the CM fundamental component and its harmonics in real time. The system was extensively validated in experimental animal surgeries by performing nerve compressions and manipulations.

Medical & Legal Issues Regarding Brain Injury

What are the medical and legal aspects of Brain Damage or Axonal damage? 

what type of knowledge is neccessary to deal with court cases that may require background knowledge and expertise in looking at the area of brain damage and discuss the intricacies of brain damage and axonal damage to the court officials as well as to the lay people in the jury??. This following article appeared in the latest issue of the newsletter of IBIA (International Brain Injury Association) discusses in detail about what health care professionals should know?.

Medical-Legal Illustration: What Health Care Professionals Should Know

By Robert L. Shepherd, MS, Certified Medical Illustrator, Vice President and Director of Eastern Region Operations, MediVisuals Incorporated

Professionals of numerous medical as well as health care subspecialties are often called upon to provide expert opinions in the context of litigation. Those providing medical-legal opinions may either be called due to their role as a treater of a patient involved in litigation or retained to provide so called “expert witness” testimony because these specialists are recognized as experts in a specific area (even though they may not have treated a patient involved in litigation). In either case, the role of the testifying professional is very important in helping decision makers or triers of fact identify and appreciate the truth in order to achieve just resolution of the contested issue(s). 

For Instance: 

Figure 1:  Example of graphics that can aid expert testimony:  This particular series of illustrations helps demonstrate one of the most difficult concepts for layperson decision makers to appreciate – that is, how brain injuries (traumatic axonal and shear injury) can occur in an individual with only a minor, or sometimes even no significant blow to the head.  The illustrations are also particularly helpful in explaining how an individual can have these injuries, yet the injuries are not evidenced on traditional brain imaging studies such as CT or MRI.   Another very effective animation demonstrating this same phenomenon even more convincingly can be seen at the following link:  http://medivisuals.com/mildtbi

Gray's Anatomy

Gray's Anatomy, the complete Book is available online free at Bartlby.com, this is a treat to medical students, anatomy and physiology students, because it is free online.

The Bartleby.com edition of Gray’s Anatomy of the Human Body features 1,247 vibrant engravings—many in color—from the classic 1918 publication, as well as a subject index with 13,000 entries ranging from the Antrum of Highmore to the Zonule of Zinn.

Henry Gray (1821–1865).  

Anatomy of the Human Body.  1918.

TWENTIETH EDITION
THOROUGHLY REVISED AND RE-EDITED BY WARREN H. LEWIS
ILLUSTRATED WITH 1247 ENGRAVINGS 

PHILADELPHIA: LEA & FEBIGER, 1918
NEW YORK: BARTLEBY.COM, 2000 

Also available free online at