A comparison of the Ameroid constrictor versus ligation in the surgical management of single extrahepatic portosystemic shunts.

Twenty-two dogs were managed surgically for a single extrahepatic portosystemic shunt; 12 with surgical ligation and 10 with an Ameroid constrictor. Utilization of the Ameroid constrictor significantly decreased surgery time to approximately half that of the ligation technique. A decreased intraoperative and postoperative complication rate was noted with the Ameroid constrictor group. Follow-up evaluation demonstrated comparable efficacy when comparing surgical techniques. The Ameroid constrictor offered a surgical occlusion technique for management of a single extra-hepatic portosystemic shunt that was equally effective to ligation while shortening surgical time and minimizing the risks that are commonly associated with ligation of the shunting vessel.

Scintigraphic, sonographic, and histologic evaluation of renal autotransplantation in cats.

OBJECTIVE: To determine scintigraphic, sonographic, and histologic changes associated with renal autotransplantation in cats. ANIMALS: 7 adult specific-pathogen-free cats: 5 males, 2 females, 1 to 9 years old. PROCEDURE: Renal autotransplantation was performed by moving a kidney (5 left, 2 right) to the left iliac fossa. Before and at multiple times after surgery, for a total of 28 days, cats were evaluated by B-mode and Doppler ultrasonography, scintigraphy, and renal biopsy. RESULTS: By 24 hours after surgery, a significant decrease (42%) in mean glomerular filtration rate (GFR) and an increase in mean renal size (81% increase in cross-sectional area) were evident in the transplanted kidney, compared with preoperative values. By postsurgery day 28, reduction in GFR was 23%. Significant changes in renal blood flow velocity were identified in both kidneys. Consistent changes in resistive index or pulsatility index for either kidney could not be identified. When all postoperative histologic data were combined, the histologic score, indicating degree and numbers of abnormalities detected, for the transplanted kidney was significantly higher than that for the control kidney. CONCLUSIONS: Significant changes in renal function, size, and histologic abnormalities develop secondary to acute tubular necrosis in cats after uncomplicated renal autotransplantation. CLINICAL RELEVANCE: Evaluation of renal size and function may be of benefit for clinical evaluation of feline renal transplant patients, whereas measurement of the resistive index may be of little clinical value.

Treatment of perianal fistulas with ND:YAG laser--results in twenty cases.

Excision of perianal fistulas using a 1.064 micron wavelength neodymium:yttrium aluminum garnet (ND:YAG) contact tipped laser with primary wound closure was used to treat 20 dogs with perianal fistulas. Overall, 19 of 20 (95%) dogs had resolution of fistulas after one or more ND:YAG treatments. The period of resolution ranged from 10 to 42 months with a mean of 22.9 months. Sixteen of 20 (80%) dogs had resolved fistulas after one laser excision. Three of the four recurrences underwent additional laser treatments with successful results. The total number of laser procedures ranged from one to three with a mean of 1.2 procedures. Postoperatively, anal tone as judged by digital rectal examination was reduced in about 60% of the cases, but clinical evidence of fecal incontinence only occurred in four of 20 cases. This was managed effectively with diet modification. The tendency toward loss of anal tone or fecal incontinence depended on the severity of preexisting anal stenosis. On a client survey, 19 of 20 owners believed that their animals experienced less pain during defecation after surgery and rated the results as excellent or good. The overall success rate using ND:YAG laser excision compared very favorably with previously reported studies of other methods of treatment for perianal fistulas in dogs.

Gene therapy for the treatment of malignant brain tumors with in vivo tumor transduction with the herpes simplex thymidine kinase gene/ganciclovir system.

Murine retroviral vectors can infect a wide variety of proliferating mammalian cell types (e.g. lymphocytes). Non-proliferating tissues (e.g. neurons) are not transduced by murine retroviral vectors. These findings suggest that this type of vector may be useful for the selective introduction of genes into growing tumors in the brain, since the tumor is essentially the only tissue that will integrate and express the vector genes.

Reflex bradycardia during TMJ arthroscopy: case report.

A case of bradycardia occurring during TMJ arthroscopy is presented. A similar case of the TVR has not previously been reported. This reflex must be recognized by oral and maxillofacial surgeons who perform arthroscopy.

Ventriculomegaly in neurofibromatosis-1. Association with Chiari type I malformation.

Two cases of von Recklinghausen neurofibromatosis with a hitherto unreported association of ventriculomegaly and a Chiari type I malformation are described. Both cases had skeletal abnormalities at the cervicomedullary junction, contributing to neurological symptoms in 1. The literature on nontumor-related ventriculomegaly in neurofibromatosis is reviewed. The Chiari type I malformation should be considered as a cause of nontumoral ventricular enlargement in patients with von Recklinghausen neurofibromatosis.

Sign language aphasia during left-hemisphere Amytal injection.

Although it has been established that the left cerebral hemisphere subserves spoken language, the nature of brain organization for sign language remains relatively unexplored. The issue is especially important because sign language displays the complex linguistic structure of spoken languages, but conveys it through manipulation of visuo-spatial relations, thereby exhibiting properties for which the hemispheres of hearing individuals show opposing specializations. We had the unique opportunity to study a hearing signer proficient in American sign language (ASL), during the left intracarotid injection of a barbiturate (the Wada test), and before and after a right temporal lobectomy. The subject was a strong right-hander. Neuropsychological and anatomical asymmetries suggested left cerebral dominance for auditory-based language. Emission tomography revealed lateralized activity of left Broca's and Wernicke's regions for spoken language. The Wada test, during which all left language areas were rendered inoperative, caused a marked aphasia in both English and ASL. After partial ablation of the right temporal lobe, the abilities to sign and understand signing were unchanged. These data add further support to the notion that anatomical structures of the left cerebral hemisphere subserve language in a visuo-spatial as well as an auditory mode.

Experimental spinal cord trauma: potentiation by alcohol.

The effect of alcohol on the injured spinal cord in cats is assessed by use of a standardized trauma model at both nonparaplegic and paraplegic trauma forces. Prior administration of an intoxicant dose of ethyl alcohol resulted in a potentiation of the trauma response at the 100 gm-cm and 260 gm-cm contusion levels. No significant changes were noted at the higher trauma grades. The results suggest that alcohol acts synergistically with mechanical injury of the spinal cord to amplify the trauma response by increasing edema formation within the contused tissue. The mechanism by which this potentiation may occur ar possibly in the areas of antidiuresis and fluid retention from increased tissue hydration in alcohol-treated animals.

Pupil cycle time in optic nerve compression.

We measured pupil cycle time before and after treatment in 11 patients with compressive optic nerve disease. Nine patients had chiasmal tumors and two had optic neuropathy of Grave's disease. Pupil cycle time before treatment was abnormal in at least one eye of all patients and in each case, pupil cycle time improved or worsened in accordance with the response to treatment of the patient's visual acuity and visual fields. This suggests that the pupil cycle time may be used as a simple objective office test for following up patients with impaired optic nerve conduction as the result of optic nerve compression. This information is similar to that gained from visual evoked response and may be used together with other objective clinical data such as disk pallor, nerve fiber loss, and relative afferent pupillary defect.

Locked-in syndrome caused by a solitary pontine abscess.

The clinical and pathological findings in a patient with locked-in syndrome caused by a solitary pontine abscess are reported for the first time. Successful treatment of brainstem abscess rests on early and accurate diagnosis.

Coexistent empty sella and prolactin-secreting microadenoma.

The empty sella turcica may be found in people with no antecedent history of intracranial disease, as well as in those with known pituitary pathology or following therapy to the pituitary gland. We have evaluated 3 women with galactorrhea and hyperprolactinemia, 2 of whom had amenorrhea. Each had an empty sella. In all cases polytomograms demonstrated asymmetry of the sella floor with focal bony erosion, conventional pneumoencephalography showed intrasellar air, and polytomographic pneumoencephalography confirmed air limited to one side of the pituitary fossa with tumor and/or residual normal tissue on the opposite side. In 2 patients who had extensive endocrine evaluation, pituitary function was normal with the exception of hyperprolactinemia. Transsphenoidal excision of microadenomas resulted in postoperative normalization of the serum prolactin concentration and resumption of regular menses in the previously amenorrheic women.

Radiographic diagnostic evaluation and surgical treatment of multiple cerebellar, brain stem, and spinal cord hemangioblastomas.

Multiple hemangioblastomas of the central nervous system present a greater challenge in their diagnosis and treatment than do single hemangioblastomas of the cerebellar hemisphere. Improved radiographic techniques of tomographic vertebral angiography and computed axial tomography (CT) are of considerable value in the diagnosis of multiple cerebellar, brain stem, and spinal cord hemangioblastomas. Microsurgical techniques now allow for total operative removal of many of these lesions. A case report is presented to emphasize the radiographic diagnostic evaluation as well as the microsurgical technique for removal of multiple central nervous system hemangioblastomas.

The development of intramedullary cavitation following spinal cord injury: an experimental pathological study.

It is concluded from this investigation that localised intramedullary cavitation will develop following non-disruptive spinal cord trauma if the magnitude of original trauma and resulting vascular damage is sufficient. Although an adhesive arachnoiditis also occurs with similar amounts of trauma, the initial vascular damage and subsequent reparative changes within the spinal cord appear to adequately explain the cavitation observed.

Chromophobe adenoma manifesting as a nasopharyngeal mass.

A 64-year-old woman had a sphenoid sinus tumor and nasopharyngeal mass verified to be a nasopharyngeal chromophobe adenoma with no evidence of sellar enlargement or involvement. The possibility that this mass arose from ectopic hypophyseal tissue located in the pharynx is proposed.