Fatal cyst formation after fetal mesencephalic allograft transplant for Parkinson's disease.

OBJECT: In recent years, fetal mesencephalic tissue transplant for the treatment of Parkinson's disease (PD) has been demonstrated to hold promise, but potential complications related to growth of allograft tissue have not been well described. This report explores the development and possible causation of a fatal cyst arising from a fetal transplant in the brain. METHODS: The authors report the case of a 52-year-old woman who underwent bilateral putamenal fetal mesencephalic allograft transplant for PD at another hospital. Twenty-three months later she presented to the authors' institution in a coma. Admission computerized tomography and magnetic resonance (MR) studies revealed a contrast-enhancing mural nodule and associated large cyst arising from the left putamen and causing brainstem compression. Despite surgical decompression of the cyst, the patient did not regain consciousness. Biopsy and autopsy specimens were obtained, along with an analysis of the cyst fluid. Genotyping of the nodule and the patient's peripheral lymphocytes by using polymerase chain reaction-based microsatellite analysis was also performed. Biopsy samples and autopsy histopathological studies showed inflammatory cells, hemosiderin-laden macrophages, and astrocytosis. Scattered neurons and multiple rests of choroid plexus were also noted. The cyst had a thin wall and contained liquid that was identical in composition to cerebrospinal fluid (CSF). Genotyping demonstrated the presence of alleles in the nodule DNA that were not present in lymphocytic DNA, indicating that the nodule contained allograft tissue. CONCLUSIONS: The authors hypothesize that the choroid plexus tissue contained in the allograft resulted in CSF production and cyst formation at the transplant site, ultimately leading to the patient's herniation syndrome. The clinical history and large size of the mural nodule indicate slow growth of this allograft site and cyst over time. This case demonstrates that unusual patterns of tissue growth can occur in the brain after fetal tissue transplant and emphasizes the need for long-term monitoring of posttransplant patients by means of MR imaging. Cell sorting should be considered to ensure transplant of pure neuronal and astroglial populations.

1H MRS in acute traumatic brain injury.

The objective of this study was to demonstrate 1H MR spectroscopy (MRS) changes in cerebral metabolites after acute head trauma. Twenty-five patients (12 children, 13 adults) were examined with quantitative 1H MRS after closed head injury. Clinical grade (Glasgow Coma Scale [GCS]) and outcome (Rancho Los Amigos Medical Center Outcome Score [ROS]) were correlated with quantitative neurochemical findings. N-acetylaspartate (NAA), a neuronal and axonal marker, was reduced (P < .03-.001). In children, a reduced NAA/creatine plus phosphocreatine (Cr) level and the presence of detectable lipid/lactate predicted bad outcome (sensitivity, 89%; specificity, 89%). The first MRS examination of all patients correlated with ROS versus NAA (r = .65, P < .0001). Although most patients showed MRS abnormalities, striking heterogeneity of 1H MRS characterized the individual patients. 1H MRS identifies multiple patterns of diffuse brain injury after blunt head trauma. There was a strong correlation between MRS and outcome. Future prospective studies will be needed to determine the clinical usefulness of MRS in predicting outcome from closed head injury.

An Absolute Electric Current Probe Based on the Faraday Effect.

This paper describes the design, construction, and testing of a probe for the measurement of electric current in a circuit. This measurement is performed by using Faraday rotation produced in a beam of polarized light that encircles the current-carrying conductor. Such a probe is an absolute instrument whose calibration only depends upon the Verdet constant of the rotative medium and is independent of the dimensions or positions of the light path relative to the current. The time resolution of the probe is the optical transit time about the closed path and can in practice be reduced to a few nanoseconds.

Severe head injury. Clinical assessment and outcome.

A prospective study of 213 patients with severe head injury and Glasgow Coma Scores of 8 or less was conducted to identify, at 24 hours postinjury, the favorable and unfavorable clinical factors that relate to outcome one year later. According to the Glasgow Outcome Scale, 35 percent were classified Moderate Disability or Good Recovery, 13 percent were classified Severe Disability or Vegetative State, and 52 percent had died. The presence of intact brain-stem reflexes 24 hours postinjury in comatose patients with head injury is a prognostic sign for a good recovery. Favorable clinical signs include eye opening, pupillary reactivity, spontaneous eye movement, intact oculovestibular reflexes, and motor responses such as localizing. A prognosis of poor recovery is associated with nonreactive pupils, absent oculovestibular reflexes, and motor response of extension or no response at all. These negative signs, when present individually, were associated with only a 3 to 4 percent Moderate Disability or Good Recovery rate and an 85 to 91 percent mortality rate. The Glasgow Outcome Scale was also used to define recovery patterns at intervals during the first year after injury. Ninety percent of patients reached their highest outcome category by six months. The most frequent one-month outcome category for survivors was Severe Disability. By six months postinjury, 68 percent of these patients had made sufficient neurological progress to change their classification to Moderate Disability or Good Recovery. The 16 percent of patients classified at one month as in a persistently Vegetative State had a prognosis of poor outcome. Only 28 percent of these patients progressed in one year to the Severe Disability classification.

A new self-drilling skull traction device with flexion-extension modification. Technical note.

A new tong has been designed that can be attached to the skull using the three-prong principle. It may act as a rigid integral part of the skull, or may simply swivel in the same manner as all contemporary tongs. This ability to function as a rigid attachment allows for flexion or extension of the patient's neck if indicated. The need for incisions or extra drills has been eliminated.

Use of computerized tomography scanning in supratentorial arachnoid cysts. A report on 20 children and four adults.

Congenital supratentorial arachnoid cysts are large lesions that tend to cause severe distortion and compression of the brain, particularly in infants and children. Diagnosis of such cysts has often been delayed and uncertain in the past, but development of computerized tomography (CT) has greatly improved the ease and accuracy of their identification, helping to provide for earlier surgical treatment and better care of patients. The authors report 24 cases of congenital supratentorial arachnoid cysts, 18 of which were studied with CT scanning; this method proved very valuable in pre- and postoperative assessment in all cases, and far superior to other diagnostic methods.

Severe head injuries in three countries.

Methods for assessing early characteristics and late outcome after severe head injury have been devised and applied to 700 cases in three countries (Scotland, Netherlands, and USA). There was a close similarity between the initial features of patients in the three series; in spite of differences on organisation of care and in details of management , the mortality was exactly the same in each country. This data bank of cases (which is still being enlarged) can be used for predicting outcome in new cases, and for setting up trials of management.