Biomedical subjects
Publications and source records attributed to S S Rengachary.
We report a case of a missile injury to the brain with an unusual complication. The bullet migrated by its mere weight to a distant location through the brain parenchyma after it initially lodged in a superficial site. Instances of similar phenomena reported in the literature are reviewed.
Two cases of subdural hematoma, one acute and the other chronic, associated with cancer metastatic to the dura are reported. Various mechanisms of the association of hematomas with cancer are reviewed.
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Granulocytic sarcoma (GS) usually occurs during the course of, or as a presenting sign of myelogenous leukemia. Rarely it is found before peripheral blood or bone marrow evidence of leukemia is present. We describe a man who presented with low back pain and lower extremity weakness. He had spinal cord compression due to GS without evidence of leukemia. Only four such instances have been previously reported. Such aleukemic presentations of GS are frequently misdiagnosed. The chloroacetate esterase stain and electron microscopy are useful in demonstrating the myeloid origin of GS cells. GS lesions are probably best treated by localized radiation therapy and systemic chemotherapy.
We evaluated four patients who had occult intrasacral meningocele with multimodality radiographic imaging techniques. The clinical features, radiological findings, gross appearances of the lesion at surgery, surgical technique, histopathological features of the cyst wall, and surgical outcome are described. The role of magnetic resonance imaging in the preoperative evaluation compared with standard radiographic techniques is discussed. Theories regarding the pathogenesis of this lesion are reviewed.
Two patients are presented in whom cranial arachnoid cysts developed as diverticuli of the arachnoid membrane through small defects in the dura mater, eroded through the inner table, expanded within the diploe, and eroded the outer table of the skull. Based on observations at the time of surgery and the histological examination of these lesions, it is proposed that they are congenital in origin. Previously reported cases of "traumatic arachnoid cyst without fracture," "intradiploic cerebrospinal fluid fistula," and "middle fossa pitholes" appear to represent the same pathological process as the lesions reported in this paper. It is proposed that "intradiploic arachnoid cyst" is the most appropriate term by which these lesions should be described.
The clinical course of a patient with brain abscess due to Haemophilus paraphrophilus is described. The organism was recovered in pure culture from purulent material collected at surgery. The role of this organism as a human pathogen is reviewed.
Hemophilus influenzae type C meningitis developed in a 68-yr-old man with a cerebrospinal fluid leak which occurred after craniotomy for an olfactory groove meningioma. Hemophilus influenzae is an uncommon cause of meningitis in adults, and most reported cases have been due to type B or nontypeable strains.
Growth hormone (GH)- and prolactin (Prl)-producing pituitary adenomas were studied with immunoelectron microscopy using protein A-gold complex, and were compared with the normal pituitary gland. GH-producing cells were readily identifiable by numerous, uniformly dense, round secretory granules in both adenomas and normal pituitary gland. In contrast, Prl secretory granules in normal pituitary gland were much larger in size than the scarce, smaller, secretory granules of Prl-producing adenomas. Thus immunoelectron microscopic identification of Prl is more valuable for prolactinoma. With more specific antigens available as tumor markers, immunoelectron microscopy appears to be a powerful tool for tumor diagnosis.
A case of hemipontine hematoma from the rupture of a cryptic vascular malformation presenting as a cerebellopontine angle tumor is reported. The clinical features of and surgical approaches to partial pontine hematomas are briefly reviewed.
Thirteen cases of CNS hemangioblastoma were examined with the immunoperoxidase technique for glial fibrillary acidic protein (GFAP) to determine if there were astrocytic elements among the "stromal cells" of these tumors. In six cases, includinng two leptomeningeal hemangioblastomas, none of the stromal cells were positive on GFAP stain. Seven cases, however, showed variable presence of Gfap positive cells, including clusters of heavily lipidized cells deep within cerebellar hemangioblastomas. These GFAP positive cells were indestinguishable by other stains from interstitial or stromal cells. Thus, it appears that in at least some hemangioblastomas of the CNS parenchyma, a few or many "stromal cells" are lipidized astrocytes. All stromal cells, however, cannot be of astrocytic origin, as proposed by Jakobiec et al. (1976), in view of our six cases where no GFAP-positive cells were found in the tumors. It is suggested that cells identified as "stromal cells" of hemangioblastomas on light microscopy are a heterogeneous group of cells including astroyctic as well as other elements and that they resemble each other on ordinary stains because of the "equalizing effect" of cell lipidization.
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Two hundred eleven adult scapulae were examined and quantitative data pertaining to the dimensions of the suprascapular notch were obtained. Six types of suprascapular notch were observed. Transitions tended to occur between Types II, III, and IV. A classification function was developed utilizing the measured values of the dimensions of the suprascapular notch, which might help in assigning the scapulae to these transitional types. Dissections of the suprascapular area were performed in 15 cadavers. Static and dynamic relationships of the suprascapular nerve to the suprascapular foramen were examined.
The suprascapular ligament seems to serve no defined function in the human. A comparative study was undertaken to elucidate its function. The suprascapular region was dissected in species representing seven existing primate families and six subprimate families. A striking dichotomy of pattern was observed. In the New World primates, the suprascapular ligament appeared to be continuous with the coracoclavicular ligament; the former merely served to increase the area of bony attachment of the coracoclavicular ligament. In the Old World monkeys and subprimate mammals, the suprascapular ligament was entirely absent. The human anatomy was comparable to that found in the New World primates. This dichotomy of pattern seems to be related to the function of the upper extremity in the different classes of mammals.
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Angiographically documented aneurysms and arteriovenous fistulae of the intraorbital segment of the ophthalmic artery are extremely rare. A unique patient is presented who had both lesions within the same orbit. History of this disease entity is traced briefly, pertinent anatomy and embryology are reviewed, and an explanation is offered on the pathogenesis of these lesions based on embryology.
The pathogenesis of intracranial arachnoid cysts is reviewed. Light and electron microscopic features of arachnoid cysts are presented in support of the hypothesis of Starkman et al, that these cysts are truly intraarachnoid in location and are formed by splitting or duplication of the arachnoid membrane. Documentary evidence is provided to prove that Richard Bright's original description in 1831 contains these concepts, which have passed unnoticed for nearly a century and a half. A brief description of the meninges and the subarachnoid spaces is given.
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