Brain Injury Lawyer

PET scans are able to objectively document functional abnormality in the brain due to trauma better than a CT or MRI. Based on the PET scans overwhelming and highly documented acceptance in the medical community, courts around the country have found PET scans admissible and have admitted expert testimony with regard to their use.

Positron Emission Tomography, also called PET imaging or a PET scan, is a diagnostic examination that involves the acquisition of physiologic images based on the detection of positrons. Positrons are tiny particles emitted from a radioactive substance administered to the patient. Brain trauma often results in subtle changes in brain anatomy and physiology, but may have market effects on condition, motion and the person's experience of life. The physiological changes underlying these long-term effects of brain injury may be detected via PET scans of the brain. These measure the metabolic activity distribution in the brain and are a very sensitive way of detecting and measuring any functioning abnormalities in the brain underlying the subjective experiences of those insured.

What makes PET scanning dramatically different from CT and MRI is PET'S ability to image brain functioning, as well as structure. PET is unique because it produces images of the body's basic biochemistry or function. PET can reveal changes in the brain's organic processes and biomechanical functions, as well as diseases with which there is no gross structure abnormality, such as Alzheimer's disease.

Before the examination begins, a radioactive substance is produced in a machine called a cyclotron and attached, or tagged, to a natural body compound, most commonly glucose. Once this sub-stance is administered to the patient, the radioactivity localizes in the appropriate areas of the body and detected by the PET scanner.

Scientifically Valid and Reliable
PET scans are a routine diagnostic tool which can be found throughout the United States and the world. Not only can PET be found at some of the top medical centers in the world, such as University of Pennsylvania (HUP), NIH, the Mayo Clinic, and Mt. Sinai Medical Center, it can be found at Englewood Hospital and Medical Center, South Jersey PET at William B. Kessler Memorial Center, St. Barnabas Medical Center, Jersey Shore Medical Center, Chilton Memorial Hospital, Somerset Medical Center and various stand-alone facilities in New Jersey.

The data supporting the usefulness of functional brain imaging in the assessment of head trauma is extensive and includes medical articles published in peer-reviewed journals. There is an indisputable and substantial body of well accepted, peer-reviewed published studies that indicate that functional brain techniques are useful in assessing chronic neurological and behavioral deficits in patients with brain injury. PET scans are regarded as measures of brain function, which is why there are 14,320 published scientific articles concerning PET, of which 1,902 concern brain activity, 104 concern brain injury, 263 concern trauma and 480 concern Alzheimer's disease. In a Medline search for the years 1990 through 2003, there were 1,139 articles on the use of FDG scans to study brain function.

Peer Reviewed Published Studies
The value of PET scanning in diagnosing and treating brain injuries was recognized by Andrew Newberg, M.D., and Abass Alavi, M.D., head of the PET Scan Center at the Hospital of the University of Pennsylvania in the December 1996 issue of the, Journal of Head Trauma Rehabilitation. The article, "Neuroimaging in Patients with Traumatic Brain Injury," was a critical review which sought to "review and consider the current and future applications of brain imaging modalities as they pertain to the study and management of head trauma."

The article focused on CT, MRI, PET, and SPECT imaging techniques. Relating to PET scanning, the authors stated:

Cerebral metabolism is believed to be a good indicator of functional activity in patients with
head trauma. In addition, other studies have shown that hypo metabolism measured by PET images correlates with neuropsychological and language testing. Thus, PET imaging has implications for rehabilitation potential. Studies have shown that PET findings correspond well with the site and extent of cerebral dysfunction as determined by neurological and behavioral evaluations, even though CT imaging does not. The good correlation between PET and neuropsychological dysfunction may be related to the ability of PET to measure reasonable brain function regardless of structural damage observed on anatomic CT or MRI scans. This may explain why functional imaging may correlate better with neuropsychological dysfunction. Id. at 71-72.

In their discussion of an earlier PET scan study, the authors noted that "brain injury patients can have regional glucose metabolic abnormalities despite normal CT, MRI or EEG results." Id. at 72. In the article's conclusion, the authors noted that while CT is considered the imaging modality of choice in the management of acute brain injury, PET scanning "can reveal areas of hypo metabolism or hypo profusion that are not detectable by MRI or CT. PET...can also detect more lesions than CT." Id. at 76. Critically, it was noted that:

PET...[does] not have the resolution of MRI, but [its] ability to measure cerebral function may be more important for evaluating brain injury. Furthermore, studies to date have shown that PET correlate[s] better with outcome and cognitive dysfunction than do either MRI or CT. This may be of particular value in the long term management of head trauma patients, since determination of brain function may help in the evaluation of outcome after rehabilitation...

CT will remain the primary neuroimaging technique in the initial evaluation of the acute head trauma patient. However, MRI, PET and SPECT each offer important useful information that may compliment one another in determining the pathophysiology, extent of injury, and outcome patients with brain injury. Further, as the need for the rehabilitation of patients with brain injury is emphasized, the role of functional imaging may become significantly enhanced in helping predict recovery, as well as in following patients as they clinically improve. Id. at 76.

Ronald Ruff, Ph.D., a pre-eminent authority in the field of neuropsychology, and Monte Buchsbaum, M.D., found PET scans to be clinically useful to objectively document the validity of neuropsychological tests results. "Selected Cases of Poor Outcome Following a Minor Brain Trauma: Comparing Neuropsychological and Positron Emission Tomography Assessment," Brain Injury, 1994, Vol. 8, No.4, 297-308. There, Dr. Ruff and Dr, Buchsbaum found that PET scan documented neuropathology which frequently was pronounced in the frontal and anteriotemporol regions and confirmed findings of cognitive impairment seen on neuropsychological testing.

In a study by Otte and colleagues, the researchers found:

This pilot study indicates for the first time that there are abnormalities in glucose metabolism in "whiplash brain". The findings provide evidence that in most of the patients studied there. is a characteristic pattern of bilateral parieto-occipital regions of the brain. Thus brain injury in whiplash patients might have been under reported in the past. As CT or MRI showed normal brain findings in all investigated patients, combined functional imaging using PET or SPECT may be more appropriate than morphological imaging alone....

PET and SPECT, although rather costly techniques, may lend more objectivity to controversial medico legal discussion on patients with late onset whiplash syndrome and associated disorders. "PET and SPECT In Whiplash Syndrome: A New approach to a forgotten brain?" A. Otte, T. M. Ettlin, E. U. Nitzsche, K. Wachter, S. Hoegerle, G. H. Simon, L. Fierz, E. Moser, 1. Mueller-Brand, J. Neural Neurosurg Psychiatry 1997; 63:368-372 (September).

Court Decisions
Post-Daubert federal cases support the admissibility of PET scans. The earliest of these decisions is Hose v. Chicago Northwestern Transportation Co., 70 E 3d 968 (8th Cir. 1993). In Hose, the U.S. Court of Appeals for the Eighth Circuit held that the trial court did not abuse its discretion in admitting the PET scan results into evidence. The plaintiff's treating physician and expert witness had relied on the results to exclude alternative causes of the plaintiff's injury, which alternatives had been argued by the defense. The Eight Circuit noted: "There is also no question that the PET scan is scientifically reliable for measuring brain function."

In Penney v. Praxir, 116 E 3d 330 (8th Cir. 1997), the Eighth Circuit barred the use of PET scan results. However, the Eighth Circuit differentiated its decision in Penney from its earlier decision in Hose. In Penney, the Court found that plaintiff's expert's failure to take into account the effects of the medication the plaintiff was taking at the time the PET scan was performed was a critical failure to the PET scan's admissibility. The Court stated:

According to the parties' submissions, PET scan results can be affected by a person's age, medical history and medications. Because Leonard was 66 at the time of the scan it is not clear from the record exactly how accurate a comparison this control group could find. Furthermore, although persons are normally instructed to remain off medication for seven days prior to the administering of a PET scan, Leonard submitted to the test while still taking his regular medications. for his, heart condition and other maladies. None of the other control groups' subjects were on medication at the time of their PET scans and it is not clear whether these factors had any affect on the test results. However, it was plaintiff's burden to establish a reliable foundation for the' PET scan readings. On these facts, plaintiffs do not make such a demonstration and it was within the District Court's discretion to exclude the evidence. Id. at 333-334.

Although the court did not permit the PET scan into evidence there, the court did not find it to be scientifically invalid.

In the matter of Nancy Ellen Jobes, 108 N.J. 394 (1987), the court was confronted with the issue of whether the patient was in an irreversible vegetative state and if so, whether the patient's family or close friend could exercise the patient's right to choose whether to refuse life-sustaining medical treatment. During the trial, David E. Levy, an associate professor of neurology at Cornell, was retained as an expert by the Public Advocate and the guardian ad litem. Dr. Levy was the author of numerous publications on brain damage resulting from a reduction in blood flow and oxygen and the persistent vegetative state. To reach his opinion, a PET scan was admitted to support the position that the patient was in an irreversible vegetative state. Although the Supreme Court was not called to validate the PET scan, the case is instructive as it demonstrates PET's use in a clinical setting.

Dr. Alavi's opinion is that PET is the "gold standard" compared to other comparable techniques in delineating brain dysfunction. In a June 18, 2998 letter, Dr. Alavi wrote:

We now offer this methodology as a routine test to the clinicians who treat patients with head injuries. There is no question in my mind that FDG-PET imaging is of great value for this purpose and is of considerable importance in the management of these patients. I want to emphasize that the abnormalities noted in FDG-PET images may not necessarily be related to head injury and a careful clinical correlation is important in proving such association. Of course the issue of non-specificity could be raised with many diagnostic tests and is not unique to PET.

Two other cases often cited in defense briefs are U.S. v. Gigante; 982 ESupp:140 (E.D.N.Y. 1997), and U.S. v. Mezvinsky, 206 ESupp. 2d 661 (E.D.Pa. 2002). In Gigante, the court did not rule that PET scans were either scientifically invalid or inadmissible at trial. In fact, the PET scan was admitted. Rather, based on other evidence produced at trial, the trial court found the PET scan evidence to be unconvincing. The court found that its own observations of the defendant at the hearing and the defendant's interaction with the government's experts, overcame the defendant's proffered expert testimony.

In Mezvinsky, the parties each called their own experts who commented on the interpretation of a PET scan interpreted by Monte Buchsbaum, M.D. The issue there was whether defendant had the necessary mens rea to be held accountable for his actions. Defendant asserted that he suffered from bipolar mental disorder, organic brain damage and Lariam-induced toxic encephalopathy, which negated the requisite intent to deceive.

With regard to the organic brain damage, Dr. Buchsbaum conducted a PET scan on the defendant which revealed evidence of frontal organic brain damage. Dr. Buchsbaum opined in his PET scan report that it was his impression that the abnormal scan was consistent with Alzheimer's disease, toxic encephalopathy or Pick's disease. Dr. Buchsbaum did not testify.

The Court, after hearing from each side's experts regarding the PET scan, found that since neither expert could identify any-thing in the PET scan that would in any way bear on the defendant's ability to deceive, the evidence was inadmissible. The experts who did testify did not dispute PET's validity nor Dr. Buchsbaum's finding.

As Dr. Alavi noted, PET is the gold standard for objectively documenting functional abnormality in the brain due to trauma.