Biomedical subjects

J S Crutchfield

Publications and source records attributed to J S Crutchfield.

3 recordsLinked to original sources

PubMed1994

Postoperative mutism in neurosurgery. Report of two cases.

Mutism is defined as a state in which a patient is conscious but unwilling or unable to speak. It has been reported to occur in association with a multitude of conditions, including trauma, epilepsy, tumors, stroke, psychoses, and brain surgery. The cases of two patients who became mute in the immediate postoperative period are presented. The first patient developed mutism following removal of a parasagittal meningioma, and the second following removal of a posterior fossa medulloblastoma. It is believed that transient injury may have occurred to the supplementary motor cortex in the first case and to the dentate nuclei in the second case. It is interesting that these two areas are connected via pathways involving the ventrolateral nucleus of the thalamus, and that lesions of this thalamic nucleus can also lead to mutism. It therefore appears plausible that interruption of these pathways may be involved in the pathogenesis of mutism. Although mutism is an infrequent complication of brain surgery, neurosurgeons should be aware that it may occur following removal of lesions in these areas and that it is generally a transient condition.

Brain Neoplasms↗

PubMed1992

On spinal osteochondromas.

Osteochondromas (or osteocartilaginous exostoses) make up about 30% to 40% of benign bone tumors. Most are solitary lesions but some are multiple, usually with autosomal dominant inheritance. From 1% to 4% of osteochondromas occur in the spine, where they can cause a variety of signs and symptoms, including those of spinal cord or spinal root compression. The authors present five patients with osteochondromas of the spine and review the findings together with those of over 130 cases reported since 1907. The cases were divided into: 1) spinal osteochondromas in patients with multiple osteochondromas, and 2) solitary osteochondromas occurring in the spine. The age (mean +/- standard error of the mean) of patients in the first group was 21.6 +/- 1.8 years compared to 30.0 +/- 2.1 years for those in the second group (p less than 0.02). There was a significant male predominance overall (M:F = 2.5:1; p less than 0.0005). In both groups, one-half of the lesions involved the cervical spine. Symptoms are caused by pressure on adjacent structures. Spinal cord compression was reported more than twice as frequently in the multiple osteochondroma group as in the single osteochondroma group (77% vs 33%; p less than 0.0005). Computerized tomography (CT) is the imaging procedure of choice. In both groups, the majority of surgically treated patients (90% and 88%, respectively) improve, with about three-quarters of the improved patients having no residual disease or only minor deficits.

Adolescent↗

PubMed1990

Evaluation of a fiberoptic intracranial pressure monitor.

The fiberoptic device is a relatively new type of intracranial pressure (ICP) monitor which appears to offer certain advantages over conventional monitoring systems, particularly its ability to measure brain parenchymal pressures. This study was undertaken to analyze the accuracy and drift characteristics of the fiberoptic device and to compare pressures in the subdural, intraparenchymal, and intraventricular compartments. The device was accurate to +/- 3 mm Hg over a 0- to 30-mm Hg range in vitro. The maximum daily drift was +/- 2.5 mm Hg, with an average daily drift of +/- 0.6 mm Hg and an average drift over a 5-day period of +/- 2.1 mm Hg. In vivo, the pressures and waveform characteristics obtained with the fiberoptic device and with a strain-gauge transducer connected to a ventriculostomy were very similar. Alterations in ICP were induced by various therapeutic and pathological manipulations, and the pressures in the three intracranial compartments were compared. Changes in ICP appeared to be reflected simultaneously and equally in all three compartments. Furthermore, changes in ICP secondary to a unilateral mass lesion were identical in both supratentorial parenchymal compartments when measured simultaneously. It is concluded that the fiberoptic device is an accurate and reliable system for ICP monitoring; the pressures recorded in the subdural, intraparenchymal, and intraventricular compartments paralleled each other in all of the physiological and pathological states tested. Although the drift associated with this device is less than that reported for previously available systems, its maximal cumulative drift over a 5-day period of +/- 6 mm Hg is significant. Since the fiberoptic device cannot be recalibrated in situ, it is suggested that the device be replaced if monitoring is to be continued for periods longer than 5 days.

Animals↗