Neurosurgery in the malignant hyperthermia-susceptible patient

Malignant hyperthermia is a seemingly rare genetic myopathy. Hypermetabolic crisis accompanied by a rise in body temperature to as high as 44 degrees C is its hallmark. Malignant hyperthermia is usually triggered by potent inhaled anesthetics or depolarizing muscle relaxants. Because of the extraordinary risk of death in patients who are susceptible, neurosurgeons may be reluctant to operate on these patients. Three such patients were referred to the Neurosurgery Service and the UCLA Malignant Hyperthermia Center after neurosurgical procedures aborted for first episodes of malignant hyperthermia. They were anesthetized with nitrous oxide, barbiturates, opiates, tranquilizers, and nondepolarizing muscle relaxants. The patients were not treated prophylactically with dantrolene. Cardiac monitoring, end-tidal pCO2, and rectal temperatures were followed. After completion of the neurosurgical procedures, all three patients had a vastus lateralis muscle biopsy and subsequent caffeine/halothane contracture studies. The contracture study was positive in all patients. No anesthetic or surgical complication was encountered. This study demonstrates that neurosurgical procedures can be performed safely in patients at risk of developing malignant hyperthermia while they undergo appropriately selected general anesthesia.

Detailing the human tail

There have been 23 true vestigial tails reported in the literature since 1884. A new case is described, and its magnetic resonance imaging and pathological features are presented. A review of the literature and analysis of the pathological characteristics reveal that the vestigial human tail may be associated with other abnormalities. Vestigial tails contain adipose and connective tissue, blood vessels, and nerves and are covered by skin. Bone, cartilage, notochord, and spinal cord elements are lacking. Tails are easily removed surgically without residual effects. Since 29% (7 of 24) of the reported tails have been associated with other malformations, careful clinical evaluation of these patients is recommended.

Value of skull radiography, head computed tomographic scanning, and admission for observation in cases of minor head injury

A retrospective review of 373 adult patients admitted to Harbor General Hospital between 1980 and 1984 for minor closed head injury (Glasgow coma scale 13-15) was performed to determine the benefits of skull radiography, computed tomographic (CT) scanning of the head, and admission for observation. Variables reviewed were mental status, neurological examination, presence or absence of loss of consciousness, clinical evidence of basilar skull fracture, and fracture on skull radiography. The neurological examination (including mental status and Glasgow coma scale) in the emergency room was the best predictor of subsequent deterioration or the presence of an operative hematoma. The only patients with Glasgow coma scale scores of 15 who required surgical evacuation of an extraaxial hematoma had focal neurological deficits referable to hemispheric compression, with or without an abnormal mental status. A Glasgow coma scale score of 13 or 14 places the patient at risk either of having a hematoma requiring surgery or of deteriorating. We recommend that a head CT scan be obtained on all patients with Glasgow coma scale scores of less than 15, abnormal mental status, or hemispheric neurological deficits. If no operative lesion is found on the CT scan, the patient should be admitted for observation because there is still a risk of deterioration. Those with a Glasgow coma scale score of 15, a normal mental status, and no hemispheric neurological deficit may be discharged to be observed at home by a competent observer despite basilar or calvarial skull fracture, loss of consciousness, or cranial nerve deficit. No benefit was gained from skull radiography in any group.

Human endolymphatic sac: possible mechanisms of pressure regulation

The ultrastructure of the normal human endolymphatic sac (ES) has been observed by transmission electron microscopy (TEM). The role of the epithelium, the various regions of the subepithelial space and the general anatomy of the ES in pressure regulation were morphologically studied to generate testable hypotheses of human ES function. Light microscopic (LM) and TEM evidence of pressure regulatory mechanisms by endolymph resorption, mechanical factors, and secretory activity are presented. These mechanisms may be useful in designing experimental studies of the ES, and in interpretation of retrospective LM and TEM studies of patients with Menière's disease.

Appendicovaginal fistula and primary appendiceal cystadenocarcinoma

An elderly woman had an appendicovaginal fistula. Within the appendix was a well differentiated mucin-producing cystadenocarcinoma that extended through the fistula and onto the vaginal mucosal surface. The development of this fistula was probably related to the tumor and a previous hysterectomy, which allowed close proximity of the tip of the appendix to the vaginal vault.

Human endolymphatic sac: morphologic evidence of immunologic function

The ultrastructure of ten normal human endolymphatic sacs (ES), fixed immediately after death and obtained at autopsy, was observed by transmission electron microscopy. The roles of the epithelium, subepithelial space, vasculature, and ES leukocytes were morphologically studied to evaluate possible immunologic functions of the human ES. In addition, five intraosseous ES biopsies from patients undergoing translabyrinthine acoustic neuroma resection were studied using the immunoperoxidase technique to identify specific leukocyte subpopulations. Evidence of phagocytic activity included the presence of phagocytic epithelial cells, monocytes, macrophages, and polymorphonuclear leukocytes. Immune surveillance was suggested by intraepithelial and subepithelial T-lymphocytes, numerous fenestrated blood vessels, and the presence of a homogeneously staining substance within the lumina of ES epithelial tubules. No B-lymphocytes were found. The findings support the existence of a local immune system of the normal human inner ear.

A new technique to maintain closed-suction drainage catheter function

Closed-suction catheter drains offer many advantages over previously used systems in head and neck surgery. Occlusion of drains with either tissue fragments of thrombus, however, is a relatively common problem. Several methods have been proposed to restore flow to obstructed drains. These methods are reviewed and a new method is described that is efficacious, avoids wound contamination, and is relatively inexpensive.

Human endolymphatic duct: possible mechanisms of endolymph outflow

The ultrastructure of the normal human endolymphatic duct (ED) was observed by transmission electron microscopy. The role of the epithelium, the various regions of the subepithelial space, and vasculature in the resorption of endolymph was morphologically studied in order to generate testable hypotheses of human ED function. These hypothetical mechanisms of endolymph outflow at the level of the ED are a passive transcellular movement of water across the epithelium, driven by an osmotic gradient created by a subepithelial organic matrix; an active transcellular ion exchange with a passive transepithelial outflow of water, which stresses the importance of the dilated lateral intercellular spaces; and an active transcellular vacuolar endolymph outflow, whereby high molecular weight substances are removed by the ED. These mechanisms may be useful in designing experimental studies of the ED and in interpretation of retrospective light microscopic and transmission electron microscopic studies of patients with Meniere's disease.

Herpes zoster of the larynx after intubational trauma

Multiple or prolonged endotracheal intubations may result in laryngeal trauma. This case illustrates that recrudescence of latent varicella-zoster virus as herpes zoster of the larynx, with subsequent laryngeal paralysis, can complicate intubation. Consequently, physicians should strive to minimize laryngeal injury in this setting. It is advised that careful laryngeal examination follow extubation.

Papillary cystic oncocytoma and Warthin's tumor of the parotid gland

A 69-year-old white female had a left superficial parotidectomy for a papillary cystic oncocytoma. The histologic appearance was identical to Warthin's tumor except that it lacked a lymphoid component. This case suggests that the general morphology of a Warthin's tumor does not depend on the presence of lymphoid tissue or association with an intra-parotid lymph node. We reviewed 50 patients with Warthin's tumors to investigate the histogenesis of the lesion. We found that most Warthin's tumors (86%) appeared to be within lymph nodes, as indicated by the presence of a lymph node capsule or sinuses. The anatomy of intra-parotid lymph nodes in glands containing Warthin's tumors has been compared with that found in 11 parotid glands containing mucoepidermoid carcinomas. So-called heterotopic ductal inclusions may actually represent the normal intimate relationship of parotid gland to intra-parotid lymph nodes.

Diabetes mellitus and hearing loss: clinical and histopathologic relationships

We compared audiometric and clinical histories with findings in temporal bones of eight diabetics and ten normal controls matched for age and sex. The group with diabetes mellitus had significantly more hearing loss than the normal control group (p less than .01). Only patients with diabetes had microangiopathy. Patients with microangiopathic involvement of the endolymphatic sac had significantly greater hearing loss than patients without such involvement (p less than .01). Microangiopathy in the stria vascularis was highly significant in the diabetics (p less than .001); however, they did not have a significant hearing loss. Diabetic patients with basilar membrane microangiopathy had significantly lower percentages of histologically normal hair cells (p less than .05) and stria vascularis cells (p less than .05) and significantly greater hearing loss (p less than .01) than diabetic patients without such pathologic changes. Results of this study suggest that diabetic sensorineural hearing loss results from microangiopathic involvement of the endolymphatic sac and/or basilar membrane vessels.

Effect of labyrinthectomy on the endolymphatic sac. A histological, ultrastructural and computer-aided morphometric investigation in the mouse

A time sequence study of the effect of hemilabyrinthectomy on the endolymphatic sac was performed in mice. Light and transmission electron microscopy of the sac showed significant morphological changes of the epithelial lining and adjacent structures. Initially (2 and 4 days post-labyrinthectomy) the sac lumen was collapsed, but later (7 days post-labyrinthectomy) it was dilated or 'ballooned' and filled with a darkly staining homogeneous substance. This substance, which has been identified histochemically as a proteoglycan, appeared to be secreted from the epithelium of the endolymphatic sac. This finding suggests that the endolymphatic sac may be capable both of absorbing and of secreting endolymph.

Cutaneous chromomycosis in renal transplant recipients. Successful management in two cases

Cutaneous chromomycosis occurred in two renal transplant recipients from the south central United States. Both patients have been managed successfully with surgical excision of isolated lesions, and the condition of one of these has been improved but not cured with low-dose ketoconazole therapy. Even in the immunocompromised host, localized cutaneous chromomycosis may not require more aggressive systemic antifungal chemotherapy.

Tumors of the appendix: II. The spectrum of carcinoid

We reviewed the clinical data and pathologic material from 30 patients with appendiceal carcinoids. Most of the tumors were discovered incidentally in appendectomy specimens. Approximately two thirds were tiny lesions identified only by microscopic examination. One tumor metastasized to a regional lymph node. Five histologic patterns were identified. Problems in differential diagnosis may arise in interpreting the variant patterns, but these patterns appear to have no bearing on prognosis. In reviewing the literature we found that appendiceal carcinoids infrequently metastasize widely and only rarely produce the carcinoid syndrome.

Tumors of the appendix: I. Neoplastic and nonneoplastic mucoceles

We reviewed the clinical data and pathologic material on 46 patients with lesions originally interpreted as appendiceal mucocele or mucinous adenocarcinoma from two medical centers. The mucoceles, characterized by accumulation of mucus in a dilated lumen, could be divided into three distinct entities: nonneoplastic retention mucoceles (eight cases), cystadenomas (26 cases), and cystadenocarcinomas (eight cases). There were four mucinous adenocarcinomas. Retention mucoceles are associated with little morbidity and are cured by appendectomy. Cystadenomas and cystadenocarcinomas mimic the behavior of ovarian neoplasms of borderline malignant potential. Some of these lesions were associated with pseudomyxoma peritonei, but did not have systemic metastases. Mucinous adenocarcinomas without mucocele mimic the behavior of ordinary large bowel carcinoma.