Biomedical subjects

V Benjamin

Publications and source records attributed to V Benjamin.

At least 19 recordsLinked to original sources

PubMed1997

Intracranial schwannoma presenting as a subfrontal tumor: case report.

OBJECTIVE AND IMPORTANCE: Intracerebral schwannomas not associated with cranial nerves account for less than 1% of surgically treated schwannomas of the central and peripheral nervous system. Subfrontal schwannomas are extremely rare, with only 15 cases reported to date. CLINICAL PRESENTATION: A 33-year-old man presented with a 4-month history of progressive headaches and lethargy. Radiographic studies revealed a large subfrontal tumor thought to be a meningioma preoperatively. INTERVENTION: The patient underwent a craniotomy for resection of his tumor. Intraoperatively, a large extra-axial tumor arising from the floor of the left frontal fossa was encountered. CONCLUSION: Microscopic examination of the tumor revealed a schwannoma. Several theories on the possible origin of intracerebral schwannomas have been considered. Because of the age of the patient at presentation, many authors have postulated a developmental origin for these lesions. However, extra-axial schwannomas not associated with cranial nerves often present later in life, suggesting a different pathogenesis for this subgroup.

Adult↗

PubMed1995

Fluorescence and circular dichroism studies during the interactions of sulfated polysaccharides with antithrombin III.

The changes in relative fluorescence of antithrombin III (AT-III) during its interaction with sulfated xylans were compared with that of sulfated glycosaminoglycans by measuring the ratio of the increase in fluorescence of AT-III in the presence of sulfated polysaccharide to the fluorescence of AT-III alone for various mass ratios. Interactions of corn cob xylan sulfate (CCXS) and sodium pentosan polysulfate (SP-54) with AT-III resulted in enhancements of relative fluorescence which were lower than commercial heparin. At mass ratios below 1, heparan sulfate and low molecular weight heparin (LMWH) gave increases in the relative fluorescence higher than that of commercial heparin, while highly sulfated semisynthetic chondroitin sulfates A and C gave much smaller increases. The relative fluorescence enhancements of AT-III by heparan sulfate, commercial heparin, LMWH and heparin derived pentasaccharide (HDP) increased with increasing mass ratios while the enhancements by CCXS, SP-54 and the highly sulfated chondroitin sulfates A and C were reversed at higher mass ratios. The estimated dissociation constants (kd) for the interaction of AT-III and the heparin-related compounds showed that heparin sulfate and LMWH gave the lowest kd values indicating a higher affinity for AT-III while commercial heparin and HDP gave higher kd values, indicating a lower affinity for AT-III. SP-54 gave a kd value lower than CCXS, indicating a greater affinity for AT-III. A comparison of the near ultraviolet (UV) circular dichroism (CD) spectrum of AT-III alone and during its interaction with oat spelts xylan sulfate (OSXS) showed enhancements of the two aromatic amino acid regions corresponding to phenylalanine and tryptophan.

Antithrombin III↗

PubMed1994

Spinal cord meningiomas.

The patient presenting with a spinal meningioma usually has a slow indolent course of symptoms but at the time of diagnosis will have a range of neurological deficits. The diagnosis is most commonly secured with MR imaging. Safe resection of spinal meningiomas mandates a clear understanding of their growth characteristics as well as of regional anatomy. Surgical treatment of spinal meningiomas is gratifying, and the severity of preoperative neurological deficits should never deter one from withholding therapy.

Follow-Up Studies↗

PubMed1993

Occipitocervical fusion with a five-millimeter malleable rod and segmental fixation.

Although occipitocervical fusion is frequently used for instability of the upper cervical spine and the occipitocervical articulation, most currently used techniques have one or more of the following disadvantages: the necessity for sublaminar wires, the use of occipital screws, a fixed angle of instrumentation, or the necessity for routine postoperative halo immobilization. Moreover, many reported techniques are associated with a high rate of nonunion or instrumentation failure. We present our experience with a technically simple method of obtaining rigid occipitocervical arthrodesis using a 5-mm malleable rod that is fixed to the skull by a pair of wires passed through four suboccipital burr holes. Segmental spinal fixation is achieved with Wisconsin interspinous wires and is occasionally supplemented with sublaminar wires. Supplemental autogenous bone graft is used in all cases. A cervical collar is routinely used for postoperative immobilization. The results of treatment were retrospectively reviewed in 16 patients with an average age of 49.4 years (range, 9-69). Mean follow-up was 24 months (range, 12-36 mo). The indication for fusion was instability of the occiput-C1-C2 complex as a result of Chiari malformation, rheumatoid disease, skull base tumor resection, basilar invagination, ankylosing spondylitis, Down's syndrome, cervical laminectomy, and trauma. The average number of levels fused was 5.4 (range, O-C3 to O-T3). Successful occipitocervical arthrodesis was achieved in all but one of the surviving patients. The single patient with a pseudarthrosis was successfully managed with supplemental bone grafting and halo immobilization. There were two deaths from medical complications in chronically ill patients. Other complications included one postoperative instrumentation loosening, one myocardial infarction, and one superficial occipital decubitus. In conclusion, rodding and segmental interspinous wiring is an effective, technically simple method of obtaining rigid occipitocervical fixation, which obviates the need for bulky orthoses.

Adolescent↗

PubMed1990

Potential misinterpretation of cervical spondylosis with cord compression caused by metallic artifacts in magnetic resonance imaging of the postoperative spine.

Tiny metallic particles produced by the contact of untempered surgical instruments with a diamond drill produce magnetic susceptibility artifacts that can both limit the diagnostic quality of postoperative magnetic resonance imaging of the cervical spine and cause diagnostic error. A case of cervical pseudospondylosis with apparent cord compression due to such an artifact is presented. The source of these metallic particles is considered, and the nature of the susceptibility artifact is discussed.

Female↗

PubMed1989

Comparative study of pentoxifylline vs antiaggregants in patients with transient ischaemic attacks.

Out of 235 patients with recent cerebral transient ischaemic attacks, 208 subjects were available for final evaluation after 6 months' randomised treatment with either pentoxifylline (PTX 1200 mg/day) or a combination (ASAD) of acetylsalicylic acid (ASA, 1050 mg/day) and dipyridamole (D, 150 mg/day). Prevention of TIA, stroke or death attributable to previous events were endpoint criteria. The pentoxifylline group (n = 100) exhibited no recurrent episodes in 86 patients (86%). TIA occurred in 9 patients, stroke in 5 patients and there was 1 death. In the ASAD group (n = 108) no recurrence of ischaemic episodes was recorded in 82 cases (75.9%). TIA occurred in 20 patients, stroke in 6 patients and there were 3 deaths of vascular origin. Side effects were recorded in 4 ASAD and 1 PTX patients. The total rate of recurrence was 14% with PTX as compared to 24.1% with ASAD treatment.

Aged↗

PubMed1984

CT of lumbar spine disk herniation: correlation with surgical findings.

Computed tomography (CT) of the lumbar spine was performed with selectively positioned 5-mm-thick axial cross sections to examine each disk level from the top of the neural foramen to the pedicle of the next caudad vertebra. One hundred consecutive patients with 116 surgical disk explorations were reviewed. There was agreement between the CT and surgical findings in 89 patients (104 explorations) in determination of presence or absence of a herniated nucleus pulposus (HNP). Discrepancy occurred in 12 instances (11 patients): two because of incorrect interpretations, five in previously operated patients, three in spondylolisthesis, and two in spinal stenosis. There were 97 true-positives, eight false-negatives, seven true-negatives, and four false-positives. If nine previously operated patients are excluded from the study, then CT was accurate in detection of presence or absence of an HNP in 93% of the disk explorations.

Adult↗

PubMed1984

Somatosensory evoked potentials during spinal angiography and therapeutic transvascular embolization.

Somatosensory evoked potentials (SEP's) were monitored during 42 angiographic examinations and 33 therapeutic embolization procedures in 41 patients. The SEP amplitude decreased in 36 of the 42 angiographic techniques, but recovered to baseline within 2 to 4 minutes in all but one case. Angiographic opacification of the anterior spinal artery reduced SEP amplitude in all but two patients, who had lost their proprioceptive sense and had no recognizable SEP prior to the procedure. No neurological complications resulted from any of the angiography procedures. Of the 33 embolizations, 15 were performed in 12 patients with arteriovenous malformations (AVM's) and 18 in 17 patients with spinal canal tumors. There was only one complication associated with embolization: that occurred in a patient with an intramedullary spinal cord AVM. Monitoring SEP amplitude in this series of patients provided a means of rapidly and reliably identifying the anterior spinal artery, served to assess the potential risk of contemplated steps in embolization, and aided in the execution of the angiographic procedures.

Angiography↗

PubMed1983

Diagnosis and management of thoracic disc disease.

In the last decade there has been a decided improvement in the diagnosis and surgical treatment of thoracic disc protrusions. This has been made possible through the development of water-soluble myelography, CT scan, high speed drills, bipolar coagulation, intraoperative magnification, and the direct frontal approaches to these lesions. Results of surgery have been rather spectacular. These results parallel, if not surpass, the improvements made in the treatment of aneurysms and benign tumors by neurological surgeons. The morbidity rate of 33% has been reduced to less than 1% due to these advances (Table 30.5) (3).

Humans↗

PubMed1982

Acromegaly and spinal stenosis. Case report.

Spinal stenosis is a well defined clinical entity that is occasionally encountered in patients with acromegaly. Persistent elevation of growth hormone promotes hypertrophy of the bones and ligaments, resulting in widening of the thoracolumbar vertebral bodies, and developmental narrowing of the spinal canal. This report describes the case of a 54-year-old acromegalic man with a 30-year history of low-back pain. Who developed symptoms of spinal stenosis. This case and two similar cases from the literature are discussed, and the appropriate therapeutic approaches reviewed.

Acromegaly↗

PubMed1982

Early surgical management of acute spinal cord injury.

Acute surgical decompression accompanied by stabilization and fusion is a safe procedure in patients with spinal cord injury. No patient was made worse by surgery. Patients with partial preservation of function and myelographic defects, i.e., surgical candidates, made better recoveries than those with normal myelograms who were, therefore, not operated upon. These results probably signify greater intrinsic cord damage in the nonsurgical group, but confirm the safety of surgery. We doubt the value of decompression for swollen cords except where there are hematomas. The treatment of cord swelling and ischemia will depend on improved pharmacological regimens.

Adult↗

PubMed1981

Rheumatic fever and rheumatic heart disease in rural South Indian children.

A preliminary pilot study of streptococcal infection and sequelae was initiated in 23 villages in 1973 using trained field workers for case detection. Part of the pilot programme, in 1974-75, involved 374 rural and 664 urban schoolchildren, and revealed that 14.9% of them had streptococcal pyoderma while pharyngitis was seen in 4.2%. The pilot study also revealed a high prevalence of rheumatic fever (RF) and rheumatic heart disease (RHD) in both rural (5.4/1000) and urban (6.0/1000) pupils. A long-term surveillance study was then undertaken in 3890 pupils attending 15 rural schools, from July 1975 to December 1978, when the prevalence of RF was found to be 0.5/1000 and of RHD, 4.4/1000, giving an overall rate of 4.9/1000. The incidence rate was found to be 1.7/1000 per year in 1976, 1.6/1000 per year in 1977, and 0 in 1978. The rate of compliance with primary prophylaxis was 90-100%, and with secondary prophylaxis was 92-93% of the 27 cases.

Adolescent↗

PubMed1980

Benign osteoblastoma of a thoracic vertebra. Case report.

A patient with osteoblastoma of the T-11 vertebral body presented with symptoms of spinal cord compression. Six weeks after an emergency laminectomy and subtotal removal, spinal computerized tomography disclosed residual tumor, which was totally removed via a combined anterior transthoracic approach and posterior laminectomy.

Adult↗

PubMed1977

Positive and negative contrast myelography in spinal trauma.

The myelograms of 60 acutely injured patients were reviewed. Positive contrast material (Pantopaque) was preferred in cervical and thoracic trauma manifesting bony deformity, in cervical trauma without bony deformity (in the prone position), in delineating the thoracic spinal cord in the frontal projection, and in lumbar spinal injuries. Negative contrast material (air) was preferred in cervical trauma without bony deformity, to delineate the thoracic spinal cord in the lateral projection and in chronic trauma to demonstrate cord atrophy. An experimental, water-soluble positive contrast material (Amipaque) may show the spinal cord advantageously in both the anteroposterior and lateral projections and may be more extensively used. A protocol has been devised, based on the analysis of the myelographic findings.

Adult↗

PubMed1977