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M S Edwards

Publications and source records attributed to M S Edwards.

At least 55 records · Page 3Linked to original sources
PubMed1996

Lower urinary tract function in ambulatory children with spina bifida.

OBJECTIVE: To investigate lower urinary tract function in ambulatory children with myelomeningocele. PATIENTS AND METHODS: The urological course of 45 children with myelomeningocele who walked either independently (19 children) or with ankle-foot orthotics (26 children) was reviewed. Follow-up ranged from 9 months to 13.5 years (mean 4.75 years). RESULTS: A normal pattern of voiding was observed both clinically and during urodynamic evaluation in only three of the 45 children, with the remainder displaying neurogenic lower urinary tract dysfunction. The independent walkers and those with orthotics did not differ in the spectrum of lower urinary tract dysfunction or other variables. Those patients with persistent incontinence underwent an initial urodynamic evaluation when older (mean 3.7 years versus 6.4 weeks in those who were continent). CONCLUSION: Ambulatory children with myelomeningocele suffer the full spectrum of lower urinary tract dysfunction. Given the potential danger of untreated lower urinary tract dysfunction, ambulatory children with myelomeningocele should receive the same diagnostic and therapeutic attention as their peers with more overt neurological deficits.

Adolescent↗
PubMed1996

Quantitative determination of antibodies to type III group B streptococcal polysaccharide.

The susceptibility of neonates to invasive infection with type III group B streptococci (GBS) in a radioactive antigen-binding assay (RABA) has been correlated with low maternal serum levels of capsular polysaccharide-specific antibodies. An ELISA was developed using capsular polysaccharide covalently coupled to human serum albumin. In sera from 35 healthy women, the range of IgG antibodies to GBS III polysaccharide was 0.05-33.0 micrograms/mL, and specific IgA antibodies were 0.08-1.1 micrograms/mL; however, no GBS III capsular polysaccharide-specific antibodies of the IgM isotype were detected by the ELISA. The levels of naturally acquired and vaccine-induced antibodies obtained with this ELISA correlated well with the results of the RABA (Spearman's rank correlation coefficient, .92). The ELISA has two major advantages over the RABA: It measures specific isotypes and subclasses of antibodies, and it can detect type III polysaccharide-specific antibodies at lower concentrations.

Animals↗
PubMed1996

Interleukin-6 production by human neonatal monocytes stimulated by type III group B streptococci.

The subcellular components of type III group B streptococci (GBS) that contribute to the host inflammatory response were determined by measuring production of the proinflammatory cytokine interleukin (IL)-6 by cord blood monocytes. Monocytes were stimulated with encapsulated (COH1) or unencapsulated (COH1-13) whole type III GBS or with purified GBS components, including type III capsular polysaccharide (III-PS), group B antigen (GB-Ag), lipoteichoic acid (LTA), or Escherichia coli lipopolysaccharide. Monocytes exposed to COH1 and COH1-13 released similar amounts of IL-6. GBS III-PS, GB-Ag, and LTA each induced IL-6. However, IL-6 release by monocytes was significantly greater after stimulation by GB-Ag than by III-PS or LTA (P < .05). Sera from 16 neonates with systemic GBS disease had IL-6 levels of 8 pg/mL to 4.28 ng/mL. GB-Ag is a potent inducer of IL-6 and may play an important role in tissue inflammation during GBS infection.

Adult↗
PubMed1996

Roles of the bacterial cell wall and capsule in induction of tumor necrosis factor alpha by type III group B streptococci.

Group B streptococci (GBS) are the major cause of sepsis and fatal shock in neonates in the United States. The precise role of tumor necrosis factor alpha (TNF-alpha) in the development of human GBS sepsis has not been defined; however, whole GBS have been shown to induce the production of this inflammatory cytokine. We sought to determine which bacterial cell wall components of GBS are responsible for triggering TNF-alpha production. Human cord blood monocytes were stimulated with encapsulated (COH1) or unencapsulated (COH1-13) whole type III GBS or with purified bacterial components, including type III capsular polysaccharide (III-PS), group B polysaccharide (GB-PS), lipoteichoic acid (LTA), or peptidoglycan (PG). Lipopolysaccharide from Escherichia coli served as a control. Supernatants were harvested at specific timed intervals, and TNF-alpha levels were measured by enzyme-linked immunosorbent assay. Monocytes exposed to COH1 and COH1-13 induced similar amounts of TNF-alpha. III-PS, GB-PS, LTA, and PG each induced TNF-alpha in a time- and concentration-dependent manner. However, TNF-alpha release was significantly greater after stimulation by the GB-PS or PG than after stimulation by III-PS or LTA (P < 0.05). Our findings indicate that GB-PS and PG are the bacterial cell wall components primarily evoking TNF-alpha release. These, alone or in concert with other factors, may be responsible for septic shock accompanying GBS sepsis.

Bacterial Capsules↗
PubMed1996

Radiologic classification of brain stem tumors: correlation of magnetic resonance imaging appearance with clinical outcome.

Although tumors of the brain stem have traditionally been classified as a single entity, these tumors are increasingly being recognized as a heterogeneous group, with some subgroups having better prognoses for long-term survival. Although several systems for classification of brain stem tumors have been proposed, none have been based on data derived from contrast-enhanced magnetic resonance (MR) imaging. In this review, we present a classification scheme based on our review of the literature and of the MR scans of 64 patients with brain stem tumors. In addition, we assess the contribution of gadolinium to the classification of brain stem tumors and correlate the various tumor subtypes, based on MR appearance, with prognosis. Our results suggest that the most important factor in determining prognosis based on MR characteristics is whether the tumor is diffuse or focal. Focal tumors have an excellent prognosis regardless of the site of tumor origin. Diffuse tumors of the mesencephalon and pons have a significantly poorer prognosis than focal tumors (p = 0.0013), with diffuse pontine tumors having the worst prognosis. Differentiation of diffuse and focal medullary tumors was difficult, possibly explaining the lack of significant difference in the survival of patients with diffuse versus focal medullary tumors. The presence or absence of enhancement after the administration of paramagnetic contrast has no significant relation with outcome, overall or within specific tumor subgroups.

Adolescent↗
PubMed1996

Gamma knife radiosurgery in children.

52 pediatric patients were treated with radiosurgery at the University of California, San Francisco. Arteriovenous malformations were treated in 27 patients. Complete obliteration was noted in 4 of 12 patients imaged more than 2 years after radiosurgery. Arteriovenous malformation rebleed was noted in 1 patient. Symptomatic T2 changes were noted in 2 patients. Among 29 neoplasms treated in 25 patients, local control was noted in 5 of 7 low-grade gliomas, 5 of 14 high-grade gliomas, 4 of 5 craniopharyngiomas and 3 of 3 sarcomas. Three patients treated for neoplasms developed necrosis after radiosurgery.

Adolescent↗
PubMed1996

Long-term follow-up after high-activity 125I brachytherapy for pediatric brain tumors.

A retrospective review including long-term follow-up (4.6-12.0 years) was performed of all 28 pediatric patients who underwent high-activity 125I brachytherapy at the University of California, San Francisco, for primary or recurrent brain tumors from 1980 until 1991. There were 4 glioblastomas, 11 high-grade nonglioblastoma multiforme (NGM) malignant gliomas, 10 contrast-enhancing low-grade NGM, 2 choroid plexus carcinomas, and 1 rhabdomyosarcoma. The 13 survivors included 7 of 8 patients with primary high-grade NGM, 2 of 3 patients with primary low-grade NGM, and 3 of 7 patients with recurrent low-grade NGM. Necrosis (with or without tumor) was identified in 17 of 22 reoperated patients. The mean Karnofsky performance status was 88 +/- 9 at the time of brachytherapy, 87 +/- 7 at 3 years, and 87 +/- 9 in 11 patients alive at 6-12 years. Brachytherapy is a useful modality for treating selected pediatric brain tumors, and although focal necrosis is a common sequela, it does not tend to have a major impact on the Karnofsky performance status, if the implant site is amenable to reoperation.

Adolescent↗
PubMed1996

Treatment of high-risk medulloblastoma and other primitive neuroectodermal tumors with reduced dose craniospinal radiation therapy and multi-agent nitrosourea-based chemotherapy.

PURPOSE: To investigate toxicity, and progression-free survival (PFS) of children and adults with newly diagnosed medulloblastoma, pineoblastoma, and other primitive neuroectodermal tumors (PNET) with a combined modality regimen of radiation therapy and adjuvant nitrosourea-based chemotherapy. PATIENTS AND METHODS: Between 1984 and 1992, 34 evaluable patients with newly diagnosed tumors were treated with chemotherapy and radiotherapy according to a single-arm phase II study. One cycle of chemotherapy was given prior to and for 6 cycles following craniospinal radiotherapy (CSA). Procarbazine, 6-thioguanine, and dibromodulcitol were given before lomustine (CCNU) to enhance CCNU-induced tumor cell kill and to reduce alkyltransferase repair of ethylated DNA. Vincristine was given 1 and 3 weeks after CCNU to kill cells that began to cycle after the challenge of the first four drugs. Chemotherapy was given in the outpatient setting. CSA radiation was planned to deliver a dose of 54 Gy to the primary tumor site and 24 Gy to the rest of the neuroaxis. Additional radiation was given to bulky disease outside the primary site if present. Hydroxyurea was used during radiotherapy as a radiosensitizer. RESULTS: Patients treated included 27 with medulloblastoma, 5 with pineoblastoma, and 2 with supratentorial PNET. All but 3 medulloblastoma cases were considered high risk either because of bulky residual disease remaining after surgery and/or metastatic disease detected during staging. For the 34 patients, 24 have progressed, 20 have died. Overall estimated PFS was 55% at 3 years and 35% at 5 years. The 5-year survival estimate is 56%. One patient had inadequate staging to determine M stage. Of the remaining 33 patients, there were 19 patients who had metastatic disease at diagnosis (M1 or higher stage) who had a 3- and 5-year PFS of 42 and 21% respectively and 5-year survival of 42%. There were 14 patients who had negative staging (M0 stage) who had a 3- and 5-year PFS of 69 and 52% respectively and 5-year survival of 71%. Of the 27 patients with medulloblastoma, 15 had M1 or higher stage. These 15 patients had a 5-year PFS and overall survival of only 20 and 40% respectively. Medulloblastoma patients with M0 staging had a 5-year PFS and overall survival of 52 and 73% respectively. Overall toxicity was primarily due to mild hematological toxicity and related to the use of the chemotherapy. CONCLUSIONS: The results using this therapy in high-risk groups of patients does not offer any improvement over results reported in other recent studies. The reason for these results may be due to the lowered craniospinal radiation dose.

Adolescent↗
PubMed1996

Skull base and calvarial deformities: association with intracranial changes in craniofacial syndromes.

PURPOSE: To analyze the skull and brain malformations in patients with craniofacial syndromes. METHODS: A retrospective analysis of imaging studies of 21 children with craniofacial anomalies (8 with Apert syndrome, 6 with Pfeiffer syndrome, 4 with Crouzon syndrome, 1 with Robert syndrome, 1 with Coffin-Lowry-syndrome, and 1 with Saethre-Chotzen syndrome) was carried out using CT (21 patients), MR imaging (9 patients), and MR venography (2 patients). A series of qualitative and quantitative assessments of the skull base and intracranial structures was performed. RESULTS: Skull base abnormalities were present in all patients. Intracranial abnormalities included ventriculomegaly, frank hydrocephalus, callosal anomalies, hypoplasia/absence of the septum pellucidum, hypoplasia/dysplasia of the hippocampus, dysplasias or distortions of the cerebral cortex, and parenchymal hemorrhage. The anomalies of the corpus callosum, septum pellucidum, and hippocampus appeared primary, whereas the others may have been the result of brain distortion by the calvarial anomaly. MR imaging was more useful than CT for evaluating brain abnormalities. In the two patients in whom it was performed, MR venography showed anomalies of the venous system, indicating that venous anomalies, possibly related to the skull base hypoplasia, may contribute to the intracranial abnormalities. CONCLUSION: A wide range of neuroimaging abnormalities are present in the craniofacial syndromes. Some of these are clearly primary, whereas others appear to be related to the small skull base and sutural synostoses. MR venography may prove useful in defining the cause of some of the associated anomalies.

Acrocephalosyndactylia↗
PubMed1996

Evolution of high-intensity basal ganglia lesions on T1-weighted MR in neurofibromatosis type 1.

PURPOSE: To characterize the temporal evolution of the foci of T1 shortening in basal ganglia lesions in patients with neurofibromatosis type 1 (NF-1). METHODS: A retrospective review of MR images of 37 patients with NF-1 revealed 8 patients in whom regions of T1 shortening were noted in the basal ganglia. We reviewed sequential images obtained in these selected patients with special attention to chronological changes in the foci of T1 shortening and their relationship to changes on T2-weighted images. RESULTS: Regions of short T1 in the globus pallidus were observed in 8 patients. In 2 of 3 patients in whom foci of T1 shortening were not identified on the initial imaging study, T1 shortening developed and T2 prolongation diminished after an initial increase. In the third patient, T1 and T2 prolongation appeared simultaneously. Sequential scans in the other 5 patients, in whom areas of increased signal intensity in the globus pallidus were present on both T1-weighted and T2-weighted images on the initial MR examination, showed a diminution in the size of the region of T2 prolongation in 2 patients, an increase in the size of the region of T2 prolongation in 1 patient, a mixed pattern of change in the size of the region of T2 prolongation in 1 patient, and no change in the region of T2 prolongation in 1 patient. During the periods of these T2 changes, the areas of T1 shortening showed no significant interval change. CONCLUSION: The foci of prolonged T2 relaxation in the basal ganglia appear to evolve in a manner similar to the foci of T2 prolongation in the white matter of the posterior fossa. However, the corresponding foci of short T1 in the basal ganglia may evolve with a different time course. In some patients, the foci of short T1 develop at a later time than the T2 prolongation and progress; these foci of short T1 do not appear to regress over periods as long as 90 months. Possible causes of the T1 shortening are remyelination and calcification.

Adolescent↗
PubMed1995

Radiation therapy for primary intracranial germ-cell tumors.

PURPOSE: To evaluate the diagnosis, therapy, and survival of patients with intracranial germ-cell tumors. To define the role of prophylactic craniospinal irradiation and chemotherapy necessary to impact on survival. METHODS AND MATERIALS: Forty-eight patients with surgically confirmed or suspected primary intracranial germ-cell tumors treated at UCSF between 1968-1990 were reviewed. Thirty-four patients had a pathologic diagnosis, including 24 germinomas, 3 malignant teratomas, 2 choriocarcinomas, 1 embryonal carcinoma, 1 endodermal sinus tumor, and 3 mixed tumors. Information obtained included histology, location, cerebrospinal fluid (CSF) cytology, alpha-fetoprotein (AFP), and beta-human chorionic gonadotropin (B-HCG), metastatic evaluation, radiation details, survival, and sites of failure. Minimum follow-up time was 2 years and ranged to a maximum of 24 years, with a median of 8 years. RESULTS: Median age at diagnosis was 16 years with 36 males and 12 females. Ten of 32 patients had elevated B-HCG at diagnosis; 6 of 29 had elevations of AFP. Cerebrospinal fluid cytology was negative in 35 of 36 patients evaluated; myelography or spinal MRI was positive in only 1 of 31 patients studied. Five-year actuarial disease-free survival after irradiation was 91% for germinomas, 63% for unbiopsied tumors, and 60% for nongerminoma germ-cell tumors with doses of 50-54 Gy to the local tumor site with or without whole-brain or whole-ventricular irradiation. Routine prophylactic cranio-spinal axis irradiation was not given with a spinal only failure rate of 2%. Eleven of 48 patients have expired, with an actuarial 5-year survival rate of 100% for germinomas, 79% for nonbiopsied tumors, and 80% for nongerminoma germ-cell tumors. CONCLUSION: With complete diagnostic craniospinal evaluation, spinal irradiation is not necessary. Cure rates for germinomas are excellent with irradiation alone. Multidrug chemotherapy is necessary with irradiation for nongerminoma germ-cell tumors. Histology is the most important prognostic factor; therefore, all patients should have surgical conformation of their diagnosis so that appropriate treatment can be given.

Adolescent↗
PubMed1995

The treatment of brain stem and thalamic gliomas with 78 Gy of hyperfractionated radiation therapy.

PURPOSE: To see whether increasing the dose of hyperfractionated radiation therapy from 72 to 78 Gy would increase survival time in patients with gliomas, particularly those with brain stem or thalamic tumors. METHODS: Seventy-eight patients with a clinical and radiographic diagnosis of a brain stem or thalamic glioma were enrolled in a trial to receive 78 Gy (1.0 Gy twice a day). Six patients with disease in other sites were also treated. The initial response to therapy was determined by comparing pretreatment magnetic resonance images and neurological examinations with those obtained within 2 weeks of completing therapy; subsequent responses were determined from bimonthly follow-up images. Time-to-tumor progression was measured from the date radiation therapy began until the date of documented radiographic or clinical progression. Survival time was measured from the date radiation therapy began until the date of death. Cox proportional hazards analysis was used to estimate the effects of specific variables on survival. RESULTS: Of 81 evaluable patients, 68 received > or = 76 Gy, 10 received between 70 and 75 Gy, and 3 received between 60 and 68 Gy. The overall response or stabilization rate was 70.4%. Tumor size decreased in 30.8% of patients; 39.5% had stable disease, and 29.6% had immediate progression. The median survival time was 12.7 months (16.1 months for adults and 10.8 months for children). The median time to tumor progression was 9.0 months (11.4 months for adults and 8.4 months for children). A duration of symptoms < or = 2 months and a diffuse lesion were each associated with shorter survival and progression times. CONCLUSIONS: For patients with brain stem or thalamic gliomas, increasing the dose of radiation therapy from 72 to 78 Gy did not significantly improve survival. Different treatment strategies are clearly needed.

Adolescent↗
PubMed1995

Clinical indicators of childhood retropharyngeal abscess.

Retropharyngeal abscess is a rare but distinctive cause of airway obstruction in childhood. Early recognition permits emergent airway management and surgical drainage. Even when the presentation is insidious and does not include respiratory compromise, early clinical diagnosis of retropharyngeal cellulitis and appropriate medical treatment may halt progression to an abscess. Delay in the diagnosis and management of a retropharyngeal abscess may lead to potentially lethal complications involving vital structures. A case of an infant whose diagnosis of retropharyngeal abscess was delayed because of absence of respiratory compromise is reported. Relapse of retropharyngeal abscess despite surgical drainage and appropriate antibiotic treatment was a complication of infection in this patient. Clinical indicators providing an early diagnosis of retropharyngeal infection, and aspects of evaluation, management, and outcome, are discussed.

Anti-Bacterial Agents↗
PubMed1995

Stereotactic insertion of an ommaya reservoir: technical note.

BACKGROUND: Stereotactic insertion of catheters into deep-seated tumors or developmental cysts is easily accomplished, but connecting the catheter to an Ommaya reservoir while maintaining catheter position can be difficult. We describe a technique for easy placement of a catheter-Ommaya reservoir construct with one pass. METHODS: Standard stereotactic imaging is performed. The distance from the outer table of the skull to the target point is measured. A catheter-Ommaya reservoir construct is assembled to this length and directed to the target position with a standard Cosman-Robert-Wells (CRW) stereotactic frame. RESULTS: Use of this technique placed catheters into tumor or developmental cysts accurately and with no surgical complications in 12 patients. CONCLUSIONS: This technique is simple, safe, reliable, and requires no special equipment. It avoids the risk of dislodging the catheter when it is being connected to the Ommaya reservoir, reducing the chances of cyst leakage and collapse.

Catheterization↗
PubMed1995

Predictive value of antepartum ultrasound examination for anomalies in twin gestations.

The purpose of this study was to evaluate the accuracy of antenatal ultrasonography in the detection of fetal anomalies among twin gestations cared for in a specialized antepartum twin clinic. A retrospective study was performed of 245 consecutive twin gestations followed in our twin clinic. The sensitivity, specificity and diagnostic indices of ultrasound to detect prenatal anomalies in the 490 infants delivered from July 1988 to October 1994 were determined. Fourteen infants had isolated congenital anomalies, and ten had multiple anomalies. The overall prevalence of congenital anomalies was 4.9%. Antepartum ultrasound examination had a sensitivity of 88% and a specificity of 100% for the detection of an anomalous infant, with a positive predictive value of 100% and a negative predictive value of 99%. The sensitivity of ultrasound for each individual anomaly within the cohort was 82%, with 100% specificity, 100% positive predictive value, and 98% negative predictive value. Our conclusions are that serial antepartum ultrasound examination of twins for congenital anomalies in our institution is very specific, with high positive and negative predictive values. The sensitivity, while also excellent, has limitations, which should be discussed with the patient.

Abnormalities, Multiple↗
PubMed1995

Group B streptococci elicit leukotriene B4 and interleukin-8 from human monocytes: neonates exhibit a diminished response.

Neonatal monocytes have diminished function compared with adult cells. The ability to recruit neutrophils through elaboration of chemoattractants has not been evaluated in humans. The pattern of chemoattractant release induced by group B streptococci (GBS) also is unknown. Adult and cord blood monocytes were stimulated with GBS. Supernatants were used as the attractant in blind well chambers; migration to neonatal supernatants was diminished. Interleukin-8 (IL-8) and leukotriene B4 (LTB4) were released in greater quantities by adult monocytes in response to either GBS or lipopolysaccharide. Opsonization of GBS was not required for IL-8 release. Adult monocytes released more LTB4 when stimulated with unopsonized GBS than with opsonized GBS; the neonate's LTB4 production did not increase. IL-8 and LTB4 accounted for the majority of chemoattractant activity released in response to GBS. Decreased production of LTB4 and IL-8 may contribute to the neonate's poor host response to GBS.

Adult↗