Marjorie Fowler

Central pontine myelinolysis, an update

Abstract Central pontine myelinolysis (CPM) can be regarded as one of the demyelinating syndromes. First described by Adams et al. in 1959 in their chronic alcoholic patients, it has now been described in the malnourished, the chronically debilitated, the renal, the hepatic and the transplant patient among others. Pathologically, it is defined as a symmetric area of myelin disruption in the center of the basis pontis, although similar symmetric lesions have also been described occurring with CPM as well as independently in other brain areas (extrapontine myelinolysis or EPM) including the cerebellar and neocortical white/gray junctional areas, thalamus and striatum. Possible mechanisms include a hyperosmotically induced demyelination process resulting from rapid intracellular/ extracellular to intravascular water shifts producing relative glial dehydration and myelin degradation and/or oligodendroglial apoptosis. The process most often occurs during rapid rebalancing of the electrolyte parameters in the hyponatremic patient. Avoidance of CPM/EPM is dependent upon recognizing those patients with conditions pre-disposing them to osmotic myelinolysis and then moderating the rate of normalization of the electrolyte imbalance. The morbidity and mortality of CPM/EPM has been greatly reduced by recognition of pre-disposing conditions, increased understanding of the pathophysiology, intensive treatment, and rapid diagnosis and monitoring with advanced neuroimaging.

Ultrasound densitometric analysis of carotid plaque composition. Pathoanatomic correlation.

BACKGROUND AND PURPOSEnThe components of a carotid artery plaque might affect the risk of ipsilateral stroke. The accuracy of carotid duplex scan in assessing stroke risk reflects the experience of the scan reader. Thus, methods that can enhance ultrasonic evaluation of plaque morphology might allow a more objective means of determining carotid-mediated stroke risk.nnnMETHODSnWe performed densitometric analysis of B-mode images of carotid plaques in nine patients scheduled for carotid endarterectomy. All patients had preoperative duplex color imaging and cerebral arteriography. The surgical specimen was analyzed histologically to determine the plaque components (soft plaque/organized thrombus, intraplaque hemorrhage/lipid deposition, fibrosis, and calcification). The specimen findings were correlated with the densitometric measurements to determine whether the density analysis would allow a reliable determination of the plaque substratum.nnnRESULTSnWith 1.0 as a reference point for the moving column of blood, the mean acoustic densities (+/-SD) were as follows: organized thrombus, 1.8 +/- 0.5; intraplaque hemorrhage/lipid deposition, 5.15 +/- 0.9; fibrosis, 9.51 +/- 2.9; and calcification, 15.5 +/- 8.6.nnnCONCLUSIONSnWe conclude that densitometric evaluation allows differentiation of the various possible components of carotid plaque. The determination of plaque composition, based on density measurement, may provide information about its potential for thromboembolization.

Intracranial astrocytoma in elderly patients

Because little is known about intracranial astrocytomas occurring in those in the increasing geriatric population, twenty-three persons evaluated at the university affiliated hospitals over a 26-year period are reported. Progressive mental dysfunctions and motor deficits were the most common manifestations of disease. Glioblastoma multiforme was the predominant (87%) histopathologic diagnosis. The overall median period of survival in 21 evaluable individuals was four (range 0 to 15) months. Median survival was longer in patients who were more functional, who had tumors located in the temporal lobes of the brain, and who received more than one treatment modality. The absence of intercurrent disease or being in a younger ‘elderly’ age group was not associated with an improvement in prognosis. The poor survival of this group as well as the survivals quoted in the literature for those with glioblastoma multiforme demands a new therapeutic approach.

Tenckhoff Catheter Obstruction Resulting From Invasion by Curvulafia Lunata in the Absence of Peritonitis

A 60-year-old black woman on continuous ambulatory peritoneal dialysis (CAPD) presented with Tenckhoff catheter malfunction. She exhibited no signs or symptoms of acute peritonitis. Darkly pigmented plaques were adherent to the inner wall of the catheter and exchange tubing focally throughout its length. Similar material was adherent to the protein coagulum in the dialysis bag. The Tenckhoff catheter and tubing were removed, and hemodialysis was initiated. Cultures of the catheter and the dialysate protein coagulum grew the saprophytic soil fungus, Curvularia lunata. Histologic examination of the catheter and tubing demonstrated penetration of each by hyphae. Catheter removal alone was sufficient to eradicate the fungus since recurrence of colonization or peritonitis has not occurred following the resumption of CAPD. Peritonitis produced by opportunistic pathogens especially fungi is increasingly common. Although Curvularia species have been implicated in pulmonary and cerebral mycetomas, allergic bronchoalveolar disease, and keratitis, they have not been reported previously to cause peritonitis or catheter malfunction in CAPD patients. Fungal invasion of CAPD catheters can produce mechanical obstruction even in the absence of peritonitis. Such colonization does not preclude resumption of chronic peritoneal dialysis at a later date.

Ultrasound of polyorchidism : case report and literature review

We report a case of polyorchidism that was suggested preoperatively by scrotal sonography. A review of the literature on this rare anomaly discloses a previously underemphasized association with malignancy.

Primary Signet Ring Cell Adenocarcinoma of the Bladder (Linitis Plastica of the Bladder): Report of a Case and Review of the Literature

Signet ring cell adenocarcinoma of the bladder is a rare tumor that usually presents as a diffuse and infiltrating neoplasm, similar to the linitis plastica type of gastric adenocarcinoma. We report the thirteenth case of primary signet ring cell adenocarcinoma of the bladder, which is documented by light microscopic, immunohistochemical and electron microscopic studies. the pertinent medical literature is reviewed and analyzed. In general, this tumor present with hematuria and irritative symptoms, and may yield equivocal radiologic and cystoscopic findings. It is characterized by a rather rapid growth rate, infiltration of the surrounding pelvic organs, and variable response to radiotherapy and radical surgery. The prognosis is apparently favorably modified by early detection of localized forms of the tumor and aggressive treatment.

Acquired immunodeficiency syndrome manifesting as prostate nodule secondary to cryptococcal infection

We report the first case of acquired immunodeficiency syndrome (AIDS) presenting as prostate nodularity secondary to mycotic granulomatous prostatitis which mimicked prostatic cancer on digital rectal examination. Transrectal ultrasonography revealed hypoechoic areas in the peripheral zone, which on biopsy specimen were found to represent cryptococcal infection. Subsequent serologic evaluation of the patient confirmed human immunodeficiency virus (HIV) positivity and later AIDS developed in the patient.

Neurologic presentations of systemic vasculitides.

Vasculitis or angiitis refers to a group of inflammatory disorders of the blood vessels that cause structural damage to the affected vessel, including thickening and weakening of the vessel wall, narrowing of its lumen, and, usually, vascular necrosis. Systemic vasculitis is classified according to the vessel size and histopathologic and clinical features. Vasculitides with small vessel involvement typically include Henoch-Schönlein purpura and cryoglobulinemia. Polyarteritis nodosa and Wegener granulomatosis are small- and medium-sized vessel vasculitides, whereas temporal arteritis and Takayasu arteritis involve large vessels. In this article, the authors provide a review of the neurologic presentations of the major systemic vasculitides.

Devic disease: clinical course, pathophysiology, and management

Devic disease is characterized by an attack or attacks of optic neuritis and necrotizing myelitis without clinical or magnetic resonance imaging (MRI) evidence of brain involvement or presence of oligoclonal bands in the cerebrospinal fluid (CSF). More than a century after its first systematic study by the French physician, Eugene Devic, its cause as well as its pathogenesis, remains unknown. Devic disease is both a diagnostic and therapeutic challenge to clinicians. The authors present the latest review on the nature, course, possible mechanisms, and therapeutic options of Devic disease.

Intraspinal synovial cysts: A retrospective study

BACKGROUNDnWe report the clinical presentation, radiographic studies, intraoperative findings, histopathological analysis, and post-treatment outcome in 26 patients diagnosed with spinal synovial cysts (SSCs).nnnAIMSnTo describe the clinical presentation, radiographic studies, operative findings, and postoperative follow-up in 26 patients with SSCs.nnnSETTINGS AND DESIGNnThe study was retrospective in design, involving chart review. Individual patient data was tabulated and patterns were recognized.nnnMATERIALS AND METHODSnThe charts for 26 patients who underwent surgical extirpation of SSC between April 1993 and October 2002 were retrospectively reviewed. Specifically, initial clinical presentation, pertinent radiographs (X-rays, magnetic resonance imaging, computed tomography), intraoperative findings, histopathology, and postoperative follow-up were noted.nnnSTATISTICAL ANALYSIS USEDnPatient data was tabulated and analyzed for patterns in demographics, symptoms and histopathology.nnnRESULTSnSSCs were more common in females than males (17:9 ratio). Presenting symptoms were back pain with radiculopathy in 13 (50%), radicular pain in the absence of back pain in 10 (38%), and back pain without radicular pain in three (11%). In addition, 17 patients (65%) had sensory deficit, and 9 (35%) had motor deficit. Most SSCs occurred at the lumbar (19/26) or lumbosacral (5/26) regions, with only 2 (2/26) in the thoracic region. One patient had bilateral SSC at the L4-5 level. Intraoperatively, each cyst was located adjacent to a degenerated facet joint. These lesions could grossly be identified intraoperatively and histopathological confirmation was achieved in all the cases.nnnCONCLUSIONSnSSCs are important lesions to consider in the differential diagnosis of lumbar epidural masses and surgical resection leads to significant improvement in the majority of cases.