Search PubMed⌕ Search

Biomedical subjects

D W Dunn

Publications and source records attributed to D W Dunn.

At least 37 records · Page 2Linked to original sources
PubMed1990

Status epilepticus in infancy and childhood.

Status epilepticus implies a prolonged seizure or recurrent seizures with persistent decreased consciousness, lasting at least 30 minutes. Both convulsive and nonconvulsive forms exist, either of which may lead to death or additional neurologic deficit. Therapy involves careful supportive care plus some combination of benzodiazepines, phenytoin, or phenobarbital. The outcome depends first on the etiology and second on the rapidity with which seizures are controlled.

Anticonvulsants↗
PubMed1989

Magnetic resonance imaging evaluation of learning difficulties and incoordination in neurofibromatosis.

Areas of increased signal seen on magnetic resonance imaging (MRI) of the brain are frequently present in neurofibromatosis and are considered possible areas of dysplasia or heterotopias. Since Rosman and Pearce [Brain 1967; 90:829-838] have shown that neuronal heterotopias in deep cerebral white matter are associated with mental retardation in neurofibromatosis type 1 (NF-1), we hypothesized that these areas of increased signal seen on MRI should be associated with learning difficulties or incoordination in children with NF-1. Using MRI, we studied 31 children with NF-1 and attempted to correlate the presence of areas of increased signal with learning difficulties or incoordination. We found no association. This suggests that either these areas of increased signal are heterotopias which are not associated with learning difficulties or incoordination, or these areas of increased signal are not heterotopias and are not relevant to the study of learning problems or incoordination in children with NF-1.

Adolescent↗
PubMed1989

Neurofibromatosis, Charcot-Marie-Tooth disease, or both?

The simultaneous occurrence of neurofibromatosis and a peripheral neuropathy that has the clinical and electrophysiological features of Charcot-Marie-Tooth disease (HMSN I) has rarely been reported. A recent report described patients with HMSN I with hypertrophic lumbosacral nerve roots. We report a patient with compelling evidence for neurofibromatosis who also demonstrates clinical and electrophysiological features of Charcot-Marie-Tooth disease. Abdominal and pelvic CT scan revealed diffusely and symmetrically enlarged lumbosacral nerve roots. These nerve roots were biopsied, and the specimens revealed neurofibromas. Histology, electrophysiological studies, radiology, and clinical appearance of the abnormality in peripheral nerves and lumbosacral nerve roots will be emphasized in this paper. The simultaneous occurrence in our patient of neurofibromatosis and Charcot-Marie-Tooth disease suggests a possible genetic relationship between these two disorders.

Adult↗
PubMed1988

Status epilepticus in children: etiology, clinical features, and outcome.

Between August 1984 and September 1986, data were gathered prospectively on 114 episodes of convulsive status epilepticus, defined as seizure duration longer than 30 minutes, affecting 97 children. Status epilepticus was symptomatic in 72% (chronic 59%, acute 13%) and idiopathic or febrile in 28%. We identified precipitating factors in 63% of episodes. The most common factors were inadequate blood levels of anticonvulsants (32 of 60 episodes in children with prior seizures) and febrile illnesses, excluding meningitis or encephalitis (38 of 114 episodes). There was an elevated peripheral white blood cell count in 60%, acidosis with a pH of less than 7.0 in 12.5%, and cerebrospinal fluid pleocytosis not due to meningitis or encephalitis in 8 of 64 episodes. Eight children died, three with severe pre-existing brain damage, two with meningitis, and two with a poorly defined encephalopathy. Eighteen children developed a new neurologic deficit. Outcome was associated with the etiology and duration of status epilepticus, with age at the time of status a minor factor. A permanent deficit occurred in only five children with idiopathic or febrile status epilepticus.

Adolescent↗
PubMed1988

Cranial MR imaging in neurofibromatosis.

Cranial MR images of 53 patients with neurofibromatosis were reviewed to determine the nature, extent, and number of intracranial abnormalities present. All patients studied met tentative definitions established for the diagnosis of neurofibromatosis. Twenty-three were scanned for evaluation of known CNS of cranial nerve involvement; the remainder were neurologically asymptomatic patients without suspected lesions referred for screening. Single lesions were noted in 32 patients. Multiple lesions were identified in 14 patients. Seven had normal scans. In 23 patients small focal areas of increased signal on T2-weighted scans within the brain were though to represent heterotopias. Eight patients had chiasmal gliomas and two had optic nerve gliomas. Nine patients had parenchymal gliomas, two had ischemic changes, and one had a colloid cyst. Extraaxial lesions included acoustic neuromas (five patients), meningiomas (four), trigeminal neurofibromas (one), and dysplasia of a sphenoid wing (two). Of the 30 asymptomatic patients referred for screening, lesions were found in 23. MR was found to be an excellent method of imaging known disease and of detecting lesions in asymptomatic patients. Because of the large number of asymptomatic lesions detected in this population, a screening MR study is recommended in patients with neurofibromatosis.

Adolescent↗
PubMed1988

Normal SPECT thallium-201 bull's-eye display: gender differences.

The bull's-eye technique synthesizes three-dimensional information from single photon emission computed tomographic 201TI images into two dimensions so that a patient's data can be compared quantitatively against a normal file. To characterize the normal database and to clarify differences between males and females, clinical data and exercise electrocardiography were used to identify 50 males and 50 females with less than 5% probability of coronary artery disease. Results show inhomogeneity of the 201TI distributions at stress and delay: septal to lateral wall count ratios are less than 1.0 in both females and males; anterior to inferior wall count ratios are greater than 1.0 in males but are approximately equal to 1.0 in females. Washout rate is faster in females than males at the same peak exercise heart rate and systolic blood pressure, despite lower exercise time. These important differences suggest that quantitative analysis of single photon emission computed tomographic 201TI images requires gender-matched normal files.

Adult↗
PubMed1987

CT in ceroid lipofuscinosis.

The diagnosis of the childhood forms of neuronal ceroid lipofuscinosis is considered when a child presents with seizures, dementia, and pigmentary change in the retina. A diagnosis is based on the result of skin or conjunctival biopsy. We report two children who had CTs obtained at the onset of seizures and prior to the occurrence of intellectual deterioration or retinal pigmentary changes. In both cases, the CT showed marked enlargement of the fourth ventricle and cerebellar atrophy without concomitant cerebral atrophy. We suggest that this cerebellar atrophy may be an early sign of ceroid lipofuscinosis and may be of particular note when seen on the CT scan of a child with a recent onset of seizures.

Atrophy↗
PubMed1985

The "muscular variant" of Pompe disease: clinical, biochemical and histologic characteristics.

We report on a 2-yr-old boy with progressive muscular weakness and respiratory failure. There was no clinical evidence of heart muscle involvement. Autopsy showed marked intralysosomal glycogen deposition in skeletal muscle and liver with no histological evidence of glycogen deposition in cardiac muscle. The activity of the lysosomal enzyme alpha-1,4-glucosidase was deficient in skin fibroblasts, skeletal muscle, cardiac muscle, and liver; however, the enzymatic activity in peripheral blood leukocytes was in the low normal range. The child's mother had normal enzymatic activity in leukocytes but heterozygote levels in skin fibroblasts.

Child, Preschool↗
PubMed1985

Continence following ileo-anal anastomosis with an antiperistaltic terminal ileal segment.

The procedure of total colectomy, excision of the rectal mucosa and ileo-anal anastomosis with or without a proximal small intestinal reservoir has been described as a method of treating patients with ulcerative colitis and familial polyposis coli. The purpose of constructing a terminal ileal reservoir is to reduce the severe diarrhoea which often occurs following ileo-anal anastomosis. It is suggested that the use of a single antiperistaltic segment for this purpose would reduce the diarrhoea, and provide continence. This has been tested in the dog and the results are reported in this publication.

Anal Canal↗
PubMed1984

Surgical morbidity after ileostomy in New South Wales.

While there have been several overseas studies on the quality of life after proctocolectomy, data concerning patients who have undergone ileostomy and proctocolectomy in Australia are limited. For this reason, a questionnaire was sent to all members of the New South Wales Ileostomy Association. Of the 354 who replied, the indication for ileostomy had been ulcerative colitis in 82%, Crohn's disease in 10%, familial polyposis in 4%; and 4% had undergone proctocolectomy and ileostomy for some other reason. Ages ranged from 15 to 93 years. Most subjects, of whom 51% were female, had had their ileostomy for a median of 9.4 years. Immediate postoperative complications related to the ileostomy occurred in 23% of patients, the most common causes being obstruction and sepsis. The rate of readmission to hospital for complications of ileostomy was a high 48%; 25% had further surgery. In view of these results, the need for continued efforts to develop alternative methods is emphasized.

Adolescent↗
PubMed1984

Factors contributing to delay in diagnosis of bacterial meningitis.

I reviewed factors contributing to diagnostic delay in 12 children who had symptoms of meningitis for more than three days before diagnosis. Prior antibiotic therapy was more common in children with delayed diagnosis. Parental factors included possible neglect in one child and passivity and failure to recognize the seriousness of the illness in six children. Physicians failed to recognize prodromal symptoms in five cases. A lack of continuity of care was a contributing factor in nine cases.

Anti-Bacterial Agents↗