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Biomedical subjects

J W Walsh

Publications and source records attributed to J W Walsh.

At least 37 records · Page 2Linked to original sources
PubMed1989

Urologic aspects of tethered cord.

Tethered cord syndrome, a form of spinal dysrhaphism, may involve vesical neurologic dysfunction. We present herein 60 cases of tethered cord syndrome, including 24 patients who underwent preoperative urodynamics studies. Preoperative cystometrography revealed areflexic bladders in 71 percent of cases and hyperreflexic bladders in 29 percent. Eight patients had serial pre- and postoperative urodynamics testing. Slight improvement was noted in postoperative urodynamics studies performed on 4 of 6 areflexic bladders and in the only hyperreflexic bladder studied. In addition, of the 3 patients in the serial urodynamics groups who had urinary symptoms preoperatively, 2 noted clinical improvement postoperatively. The urologist's role is important in the early detection, evaluation, and treatment of tethered cord syndrome and the neuropathic bladders that may result.

Adolescent↗
PubMed1989

Transfection of normal and transformed hamster cerebral cortex glial cells with activated c-H-ras-1 results in the acquisition of a diffusely invasive phenotype.

We have examined the effect of activated c-Ha-ras oncogene on the invasive phenotype of normal and tumorigenic glial cells of Syrian hamster cerebral cortex derivation. T24 ras oncogene derived from a human bladder carcinoma was transfected into normal glial cells and minimally invasive tumorigenic glial cells produced by SV40 transformation. The normal cells acquired the capacity to grow in soft agar and become tumorigenic. With ras transfection, both the normal and minimally invasive SV40 tumor cells became diffusely invasive for adjacent normal brain. (N.B.: One cell line exhibited less extensive invasion than the others.) All of the transfected cell lines exhibited high levels of ras expression. These results indicate that ras can impart tumorigenic potential to normal glial cells and progress these or minimally invasive glial cells to full invasiveness.

Animals↗
PubMed1987

Chronic septic arthritis of the adult hip: computed tomographic features.

Abnormalities on computed tomography (CT) are described in 12 adults in whom septic arthritis of the hip was diagnosed. Presenting symptoms varied, as did CT findings. Soft tissue abnormalities ranged from intra-articular effusion to large abscess formation, and bone changes ranged from minimal erosion of articular surfaces to gross destruction of the proximal femur and acetabulum. CT can be helpful in the evaluation of septic arthritis of the hip because of its superior demonstration of soft tissue detail. An accurate diagnosis can be established in unsuspected cases and can be confirmed when clinical indicators are vague.

Abscess↗
PubMed1987

Invasiveness in primary intracranial tumors: Part 2. Studies with scanning electron microscopy of cell surface alterations associated with invasiveness.

We previously described an experimental model for the production of invasive and noninvasive astrocytic series tumors and a semiquantitative assessment of their invasiveness. The tumors are produced by intracerebral inoculation of simian virus 40-transformed cells from four different brain regions. Cells of cerebral cortex and brain stem derivation produced invasive tumors; tumors of cerebral cortex derivation were more invasive and became increasingly invasive with alternate in vivo and in vitro passage. Cells of cerebellar hemisphere and vermis derivation produced primarily noninvasive tumors. This report describes the surface configuration of these tumor cells in culture at or near confluence as visualized with scanning electron microscopy. Normal cells form a multilayered base of flat, overlapping cells with few excrescences and indistinct borders and have only rare dividing or giant cells attached. Invasive tumor cells from a monolayer base of extremely flat and spread out cells almost devoid of excrescences, with few dividing or giant cells attached. Cells of cerebral cortex derivation additionally have numerous microvilli and ruffles at points of intercellular contact and become covered with microvilli after passage. These features were retained after cloning by dilution plating, but not after cloning by growth in soft agar. Our primarily noninvasive cells form a multilayered base of rounded cells covered with various excrescences and numerous attached dividing and giant cells. These surface features seem to be related to intercellular and cell-substrate adherence. The configuration of the invasive cells is consistent with increased cell-substrate adherence, substrate-dependent inhibition of locomotion, and decreased intercellular adherence among the more invasive cells. The configuration of our primarily noninvasive cells is consistent with decreased cell-substrate adherence and unrestricted multilayered growth. Thus, it seems that invasiveness is expressed at the cell surface and is related to disturbances in adherence balance rather than in cell proliferation.

Animals↗
PubMed1986

Frontal lobe lesions and cognitive function in craniopharyngioma survivors.

We performed neuropsychological testing using the Luria-Nebraska Neuropsychological Battery, computed tomography, and magnetic resonance imaging (MRI) in four patients one to 15 years after surgery and radiation therapy for childhood craniopharyngioma. Of three patients with impairment of frontal lobe-mediated cognitive function, two had extensive areas of prolonged spin-lattice and spin-spin relaxation times in the frontal lobes demonstrated by MRI, and one had a lipid accumulation in the anterior horn of the right lateral ventricle and beneath a burrhole defect in the skull. One patient with minimal cognitive dysfunction had no abnormality in imaging studies. We believe assessment of neuropsychological status is an important aspect of the evaluation of children with craniopharyngioma. We have found the Luria-Nebraska Neuropsychological Battery and MRI to be particularly useful in this evaluation.

Adolescent↗
PubMed1986

Magnetic resonance imaging of the sella turcica and parasellar region. A clinical-radiographic evaluation with computed tomography.

Thirty-one magnetic resonance (MR) scans and computed tomography (CT) scans were obtained on 25 patients in whom lesions involving the sella turcica or parasellar region were clinically suspected. Surgical pathologic studies were available in 19 cases. Twenty-two of the MR scans were of diagnostic value equivalent to that of the corresponding CT studies. In two small meningiomas, an empty sella, and a sphenoid-middle fossa tumor, MR technology failed to delineate the pathologic process adequately. In the remaining five patients, MR either more convincingly demonstrated the pathologic anatomy or yielded diagnostic information not present in the CT study. In view of the absence of ionizing radiation, high degree of tissue contrast and spatial resolution, and multiplanar capability, magnetic resonance scanning will probably become the initial imaging modality of choice in patients suspected of harboring sellar and parasellar tumors.

Adolescent↗
PubMed1986

Evaluation of children and young adults with tethered spinal cord syndrome. Utility of spinal and scalp recorded somatosensory evoked potentials.

The diagnosis of tethered spinal cord syndrome should be considered in young patients with progressive orthopedic deformities, lower extremity weakness, urinary and fecal incontinence, low back pain, or combinations of these symptoms. Myelographic, computed tomographic, and urodynamic studies are useful for establishing a diagnosis, but contribute little to the evaluation of lower extremity sensory function or to the assessment of electrophysiologic impairment of the spinal cord itself. To determine the diagnostic usefulness of the somatosensory evoked potential after posterior tibial nerve stimulation (posterior tibial nerve somatosensory evoked potential) in tethered spinal cord syndrome, 22 consecutive patients with symptoms of tethered spinal cord syndrome (aged 18 months to 22 years) underwent recording of posterior tibial nerve somatosensory evoked potential; results were correlated with clinical, myelographic, and operative findings. In patients with clinical symptoms but no myelographically demonstrable lesions, posterior tibial nerve somatosensory evoked potentials were within normal limits, suggesting normal physiologic function. In patients with myelographically and operatively confirmed tethering dysraphic lesions, posterior tibial nerve somatosensory evoked potential was predictive of the level and laterality of the lesion. Similarly, ranking the severity of neurological impairment and extent of dysraphism at operation, as well as the extent of abnormality of posterior tibial nerve somatosensory evoked potential, revealed a significant (r = 0.81, p less than 0.001) correlation between clinical severity and posterior tibial nerve somatosensory evoked potential abnormalities. Postoperatively, in 8 patients, posterior tibial nerve somatosensory evoked potential also reflected improved function in relation to the level and type of dysraphic lesion present. These findings indicate that posterior tibial nerve somatosensory evoked potential is a sensitive indicator of neurophysiologic status in patients with tethered spinal cord, and is useful for determining the level of the conus medullaris, degree of spinal cord displacement, and severity of neurological impairment associated with this congenital disturbance of neuraxis formation. Recording of posterior tibial nerve somatosensory evoked potential is noninvasive and offers a more sensitive diagnostic tool than the clinical testing of sensation for detection of the development of neurologic deficits in patients with tethered cord syndrome.

Adolescent↗
PubMed1986

Extratesticular hemorrhage associated with torsion of the spermatic cord: sonographic demonstration.

Using ultrasound (US), we studied seven patients with torsion of the spermatic cord associated with a large amount of extratesticular hemorrhage. In each case, US showed a large echogenic or complex extratesticular mass caused by the hemorrhage, in addition to a hypoechoic testis and scrotal skin thickening. This appearance should be recognized as part of the spectrum of sonographic appearances that can be seen in torsion.

Adolescent↗
PubMed1986

Upper abdominal trauma: pitfalls in CT diagnosis.

Medical records and computed tomographic (CT) scans of 83 patients with upper abdominal trauma were retrospectively reviewed to determine errors in diagnosis using CT. Patients with possible pancreatic injury, small bowel perforation, or injury to an occult malignancy represented the most difficult diagnostic cases. A false-positive diagnosis of pancreatic injury occurred in seven of 77 patients (9%) and represented the most frequent error in the series. In three patients with subsequently surgically proved small bowel perforation, one duodenal and two proximal jejunal, the injuries were not correctly diagnosed on CT scans. In retrospect, positive CT findings were present in the case of duodenal rupture. Additionally, in two patients, duodenal rupture was suspected based on CT findings of extraluminal gas and fluid near the duodenum, but both cases were proved normal at surgery. The series included three patients with trauma involving unsuspected tumors in the liver, kidney, and stomach.

Abdominal Injuries↗
PubMed1986

CT of the pulmonary nodule: a cooperative study.

To evaluate the role of computed tomography (CT) in the investigation of pulmonary nodules, a special reference phantom that enabled CT densitometric measurements independent of variations between scanners and patients was used in ten institutions. A total of 384 nodules not considered calcified by conventional methods were examined; 118 (31%) proved to be benign, and in 65 of these (55%), unsuspected calcification was demonstrated. In 28 of the 65, definite calcification could be identified on thin-section CT scans by simple inspection of the scans at narrow windows. In the remaining 37, presence of calcification could not be clearly established without comparison with the reference CT number from the calibration phantom. CT was most effective in establishing the benignancy of nodules 3 cm or less in diameter and those with discrete or smooth margins. CT rarely yields a confident diagnosis of benign disease in larger nodules and in those with irregular or spiculated borders. After review of prior spot radiographs, low kilovolt peak spot radiographs, and conventional tomograms, the authors conclude that thin-section CT aided by a reference phantom in equivocal cases should be an integral part of the diagnostic approach to the pulmonary nodule.

Adult↗
PubMed1986

Invasiveness in primary intracranial tumors: Part 1. An experimental model using cloned SV40 virus-produced hamster brain tumors.

This report presents an experimental model for study of the cellular and molecular biology of invasiveness in tumors. It uses SV40 virus for the production of primary intracranial tumors that are invasive for normal brain and vary markedly and predictably in this invasiveness. Cell cultures of dissociated 1- to 2-day-old Syrian hamster cerebral cortex (Cx), brain stem (Bs), cerebellar hemisphere (Cbh), and cerebellar vermis (Cbv) were transformed with SV40 virus and inoculated intracerebrally into newborn hamsters. All 368 animals that developed intracranial tumors were killed, and tumor was taken for histological and immunofluorescence studies, assessment of extent of invasiveness, and preparation of cell cultures from which cells were cloned by dilution plating or growth in soft agar. A few hamsters were perfused with glutaraldehyde for studies of tumor ultrastructure. All cloned and uncloned tumor cells were reinoculated to produce second- and third-passage tumors. Characteristic differences in morphology and growth rate were observed between normal astrocytes derived from each brain region, and these phenotypic differences were retained after virus transformation and tumor production. Cloned and uncloned Cx cell-derived tumors of second and third passage diffusely invaded adjacent normal brain, although those of first passage invaded only slightly. Except for extracerebral spread, these tumors resembled human astrocytic series tumors. Bs and some Cbh cell-derived tumors were also astrocytic but more undifferentiated and only slightly invasive; Cbv and other Cbh cell-derived tumors were sarcomatous and only extended along perivascular spaces or were not invasive at all. The tumor cells contained glial fibrillary acidic protein and SV40 T-antigen. These results suggest that astrocytes from different brain regions vary in genomic stability and support the theory that differences in invasiveness reflect the development of heterogeneity and subsequent selection of more aggressive subpopulations of cells.

Animals↗
PubMed1985

Brain biopsy in cases of neonatal herpes simplex encephalitis.

Neonatal herpes simplex encephalitis (HSE) can represent a difficult diagnostic problem when it occurs without concomitant mucocutaneus lesions and usually requires brain biopsy for diagnosis. Asymptomatic for the initial 2 to 4 weeks of life, the three infants we describe with localized HSE came to medical attention only because they developed persistent seizures and other nonspecific symptoms. Lumbar spinal fluid obtained from these children at clinical presentation showed an encephalitic pattern. Radionuclide brain scans revealed focal uptake of isotope in a variety of cortical areas, and electroencephalograms (EEGs) demonstrated repetitive, high amplitude, polyphasic sharp waves arising from analogous regions. Computed tomography (CT) showed nonspecific ill-defined areas of low density or contrast enhancement that did not correlate well with radionuclide, EEG, or clinical findings in two neonates. No infant had predominant temporal lobe involvement. Because these data suggested a multifocal, encephalitic process, all three infants underwent brain biopsy. A widespread infiltration of leukocytes and macrophages was observed in each specimen, and abundant intranuclear inclusions were present. Electron microscopy revealed abundant herpesvirus particles, and herpes simplex virus (HSV) was subsequently isolated from each sample. From our observations and our review of the literature, we propose the following criteria as indications for brain biopsy: Brain biopsy is warranted to rule out HSE when a neonate presents with seizures, cerebrospinal fluid mononuclear pleocytosis with a negative gram stain, and focal, cortical disease on EEG and radionuclide scan.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗
PubMed1985

Suprasellar germ cell tumor with extracranial metastases.

A case of metastasizing suprasellar germ cell tumor is described. Serum tumor markers were measured and the immunochemistry of the tumor was studied. The rarity of extracranial metastasis from suprasellar germinomas is noted, and the relevance to mixed tumors is discussed. The difficulties associated with small biopsies and the importance of tumor marker studies in all cases of an intracranial germ cell tumor are emphasized by the case study.

Adolescent↗
PubMed1985

Ventricular sepsis and abdominally related complications in children with cerebrospinal fluid shunts.

In a retrospective study of 300 children who underwent placement or revision of cerebrospinal fluid (CSF)-peritoneal shunts during a 10-year period, 15 (5%) developed shunt-related abdominal complications with ventricular sepsis and two developed acute perforated appendicitis. Abdominal complications and associated shunt infections suggested two potential modes of development: (1) descent of contaminated CSF from an infected shunt into the abdomen (CSF ascites--four patients, CSF pseudocysts--four patients, and shunt-induced abscess/peritonitis--five patients); and (2) ascent of bacteria into the shunt from an abdominal source (visceral perforation by the shunt catheter--two patients and acute perforated appendicitis--two patients). Three types of shunt systems were placed during the study period; five of the seven (71%) most serious septic complications were associated with the use of Raimondi spring-reinforced catheters. Bacteria isolated in this series were associated with differing modes of sepsis: those involving descent of bacteria into the abdomen from an infected shunt were predominantly gram-positive, cutaneous microorganisms, whereas those associated with ascent of bacteria from the abdomen into the shunt were mixed, gram-negative intestinal microorganisms. Appendicitis did not result in shunt infections. Aggressive treatment resulted in no operative or complication-related deaths. Removal of the shunt catheter from the abdomen and intravenous antibiotics were essential for eradication of sepsis; laparatomy was required only for cases with suspected peritonitis. In eight of the 17 (47%) patients, reestablishment of CSF-peritoneal shunts was performed after resolution of shunt-related complications. In recent years improved shunting materials and supportive care have reduced the incidence of the most serious of these complications.

Abdomen↗
PubMed1984

Adrenal myelolipoma: CT and ultrasound findings.

The computed tomographic (CT) and ultrasound (US) appearances of 5 adrenal myelolipomas in 4 patients are reported. The component tissues of a myelolipoma determine its CT and US appearance. A myelolipoma consisting primarily of fat has a characteristic CT and US appearance. A myelolipoma also containing macroscopic quantities of nonfatty material (blood, calcium, or myeloid tissue) may have a nonspecific CT or US appearance if fat is not identified in the lesion. In equivocal cases, needle biopsy may be used to establish the diagnosis of myelolipoma.

Adrenal Gland Neoplasms↗