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P D Adelson

Publications and source records attributed to P D Adelson.

At least 55 records · Page 3Linked to original sources
PubMed1997

Cerebrovascular response in infants and young children following severe traumatic brain injury: a preliminary report.

To further describe the pathophysiologic processes that occur in infants and young children after severe traumatic brain injury (TBI), we retrospectively reviewed the cerebral blood flow (CBF) values and 6-month Glasgow Outcome Scores (GOS) in 30 children < or = 8 years old (25 were < or = 4 years old) with a Glasgow Coma Score (GCS) on admission of < or = 8. Twelve females and 18 males (mean age 2.1 years, range 1 month to 8 years) underwent 61 CBF studies using stable xenon computed tomography at variable times from admission to 9 days after TBI. In 12 patients, PaCO2 was manipulated an average of 8.4 torr (range 5-11 torr) and a second CBF study performed to determine CO2 vasoreactivity (CO2VR), defined as the percent change in CBF per torr change in PaCO2. CBF on admission (n = 13)was 25.1+/-7.7 ml/100 g/min (mean +/- SEM) and was < or = 20 ml/100 g/min in 10 of 13 patients (77%). By 24 h and for up to 6 days after TBI, the mean CBF increased to 55.3+/-3.4 ml/100 g/min (range 2-95) which differed significantly from the admission CBF value (p < 0.05); a CBF of >70 ml/100 g/min tended to be associated with a good outcome. Poor outcome (GOS < or = 3) was seen uniformly in children under the age of 1 year and in patients with a CBF of < or = 20 ml/100 g/min any time after TBI. Poor outcome was seen in 85% of children under the age of 24 months, but in only 41% of children > or = 24 months old. Mean CO2VR was 2.1+/-0.6%/torr PaCO2 and ranged from 0.02 to 5.98%. Mean CO2VR tended to differ between good and poor outcome children (3.2+/-0.9 and 1.17+/-0.2%, respectively) and a CO2VR of < or = 2% was significantly associated with a poor outcome. Younger age, low CBF in the early period after TBI, and a CO2VR of <2% was associated with a poor outcome in this subgroup of children. Young children (<24 months) may represent a particular high-risk group with early hypoperfusion after severe TBI. This finding may be a key factor in the pathophysiology and outcome in this age group, and may need to be addressed in our future therapeutic protocols.

Age Factors↗
PubMed1997

Upper cervical spine fusion in the pediatric population.

The outcomes of 25 pediatric patients who underwent upper cervical or occipitocervical fusion at the authors' institution since 1983 were reviewed. At a mean age of 9 years, the patients presented with spinal instability that was associated with os odontoideum in 11 cases, rotatory subluxation in five cases, odontoid fracture in two cases, atlantooccipital dislocation in two cases, and congenital atlantoaxial instability in five patients, four of whom had Down's syndrome (trisomy 21). Ten children had abnormal findings on neurological examination preoperatively; however, nine experienced improvement or resolution of deficits as of their latest follow-up evaluation (mean 17 months). Fusion was achieved with the first operation in 21 of 25 patients; eventually it was attained in all but one. Four patients exhibited persistent spinal instability after an initial procedure. This was caused by erosion of a multistranded cable through the intact arch of C-2 in two cases, by pin site infection necessitating early halo removal in one case, and by slippage in a halo following a Gallie procedure, which was revised with a Brooks fusion in one case. This series, the largest yet published, shows that with appropriate surgical management, posterior upper cervical fusion in the pediatric population is highly successful. Careful attention to halo pin site care and caution in using multistranded cable in young patients may improve results.

Adolescent↗
PubMed1996

Aberrant hippocampal mossy fiber sprouting correlates with greater NMDAR2 receptor staining.

This study determined in temporal lobe epilepsy patients and rats injected with intrahippocampal kainate (KA) whether fascia dentata molecular layer mossy fiber sprouting was associated with increases in NMDAR2 immunoreactivity (IR). Patients with hippocampal sclerosis (n = 11) were compared with those with temporal mass lesions (n = 7) and material obtained at autopsies (n = 4); and unilateral KA-injected rat hippocampi (n = 7) were compared with the contralateral saline-injected side and non-lesioned animals (n = 7; control). Hippocampi were studied for neo-Timm's stained mossy fiber sprouting and NMDAR2 IR. The staining was quantified as gray values (GV) using computer image analysis. Hippocampal sclerosis patients and KA-injected rats showed the greatest inner molecular layer (IML) mossy fiber sprouting and NMDAR2 staining. Compared with autopsies and patients with mass lesions, hippocampal sclerosis patients had greater IML neo-Timm's (p = 0.0018) and NMDAR2 staining (p = 0.0063). Similarly, compared with controls and saline-injected rats, KA-injected hippocampi showed greater IML mossy fiber sprouting and NMDAR2 IR (p = 0.0001). Furthermore, IML mossy fiber sprouting positively correlated with greater IML NMDAR2 staining in both human and experimental rat groups (p < 0.0099). These results support the hypothesis that in severely damaged hippocampi abnormal mossy fiber sprouting and concordant increases in IML NMDAR2 receptor staining may contribute or partially explain granule cell hyperexcitability and the pathophysiology of hippocampal epilepsy.

Adult↗
PubMed1996

Technique of stereotactic biopsy in a 5-month-old child.

We describe a technique of stereotactic frame-based biopsy in young children who have open fontanels and a deformable skull. A 5-month-old girl with a growing lesion in the right thalamus and basal ganglia underwent stereotactic biopsy, which disclosed an anaplastic astrocytoma. To avoid insertion of the four stereotactic frame fixation pins through the infant's skin and into bone, the pins were advanced into the hollowed end of rubber tops obtained from Vacutainer blood sampling tubes. The pressure applied to the skin was diffused through the rubber onto a wide skin surface, obviating skin puncture or bone deformation. This technique provided firm head fixation, and target accuracy was confirmed on post-operative imaging. This technique is safe and should permit use of conventional stereotactic techniques in young infants.

Astrocytoma↗
PubMed1996

A meningeal cyst of the thoracic spine presenting as prolonged paresis after ankle injury: case report.

A case of a thoracic meningeal cyst causing right lower extremity weakness in a fifteen-year-old girl is presented. The diagnosis was delayed due to a history of ankle injury which was initially used to explain her symptoms. The authors explain the difficulty in diagnosing intraspinal meningeal cysts and stress the importance of surgical excision before spinal cord injury progresses.

Adolescent↗
PubMed1996

Effects of ondansetron on emesis in the first 24 hours after craniotomy in children.

Children undergoing neurosurgical resection are at high risk for postoperative nausea and vomiting. Ondansetron, a selective serotonergic (5-HT3) antagonist, is effective in reducing postoperative vomiting in several high-risk populations. In a prospective, randomized study, we compared the prophylactic use of intravenous ondansetron, 0.15 mg/kg, versus placebo for the prevention of emesis in 60 children, aged 2-18 yr, undergoing craniotomies for resective procedures. Patients with preoperative emesis were excluded from the study. All patients were tracheally extubated at the conclusion of surgery, and each episode of emesis during the first 24 postoperative hours was recorded. For the entire 24-h interval, the incidence of emesis in children who received ondansetron (57%) was not significantly different from that in those who received placebo (66%); however, in the first 8 h, the incidence was 25% (ondansetron) vs 44% (placebo) (P = not significant). In those receiving placebo, there was no difference in emesis between patients undergoing operations above versus below the tentorium. Although our sample size was too small to completely exclude any beneficial effect, ondansetron appears ineffective in preventing postoperative emesis in this patient population.

Adolescent↗
PubMed1996

Direct injury to the cervical spine of a child by a lap-shoulder belt resulting in quadriplegia: case report.

Most pediatric cervical spine injuries from seat-belt restraints result from hyperflexion of the neck without direct injury to the spine from the restraining device. We report what we believe to be the first case of direct injury to the cervical spine by the shoulder component of a lap-shoulder seat belt. This resulted in quadriplegia. The mechanism of injury and recommendations to obviate such injuries are discussed.

Accidents, Traffic↗
PubMed1996

Seizure outcome in children treated for arteriovenous malformations using gamma knife radiosurgery.

Seizures are the second most common presenting symptom of arteriovenous malformations (AVMs) in children. Although radiosurgery has been found to be a safe and effective alternative treatment, the outcome of seizure control in children after radiosurgery for AVMs is unknown. Between 1987 and 1994, 72 children under the age of 18 years were treated with gamma knife radiosurgery for AVMs at our institution. Fifteen patients (21%) had seizures as part of their clinical course. There were 11 boys and 4 girls with ages varying from 2 to 17 years (median 16 years). Seizures included: generalized tonic-clonic (n = 8); focal motor or sensory (n = 4); partial complex (n = 2), and a combination of generalized and partial complex (n = 1). Nine lesions were in cortical locations; six were subcortical. Spetzler-Martin grades included: II (n = 7); III (n = 4); IV (n = 2), and VI (n = 2). During follow-up after radiosurgical treatment, 11 of 13 patients (85%) were seizure free and off anticonvulsant therapy (mean follow-up 47 months). Two patients had a significant improvement in their seizures but continue on medication. Two of the 72 patients (3%) developed seizures after treatment and remain on medication. Seizure outcome was not associated with the location or complete obliteration of the lesion. We conclude that stereotactic radiosurgery, as a non-invasive alternative, is associated with a good outcome for the AVM as well as AVM-related seizures in children.

Adolescent↗
PubMed1996

A model of diffuse traumatic brain injury in the immature rat.

Diffuse cerebral swelling after severe traumatic brain injury (TBI) develops more commonly in children than adults; however, models of diffuse brain injury in immature animals are lacking. The authors developed a new model of diffuse severe TBI in immature rats by modifying a recently described closed head injury model for adult rats. A total of 105 Sprague-Dawley immature rats (17 days old; average weight 38.5 +/- 5.46 g) were subjected to head impact using variable weights (0 g (sham), 75 g, 100 g, or 125 g) delivered from a height of 2 m onto a metal disk cemented to the intact cranium. Mortality, physiological and neurological parameters (from early reflex recovery to escape), and early histopathological changes were assessed. During the acute period after severe injury (SI) (100 g delivered from a height of 2 m; 50 rats), apnea was frequently observed and the mortality rate was 38%. Neurological recovery was complete in the sham-injured animals (11 rats) by 4.1 +/- 0.23 minutes (mean +/- standard error of the mean), but was delayed in both moderately injured (MI) (75 g/2 m; 11 rats) (14.97 +/- 3.99 minutes) and SI (20.57 +/- 1.31 minutes (p < 0.05)) rats. In the first 24 hours, the sham-injured animals were more active than the injured ones as reflected by a greater net weight gain: 2.9 +/- 1.0 g, 1.2 +/- 1.6 g, and -0.6 +/- 2.1 g in sham-injured, MI, and SI animals, respectively. Immediately after injury, transient hypertension (lasting < 15 seconds) was followed by hypotension (lasting < 3 minutes) and loss of temperature regulation. Both injuries also induced apnea (0.75 +/- 0.7 minutes and 1.27 +/- 0.53 minutes in MI and SI groups, respectively), which either resolved or deteriorated to death. Intubation and assisted ventilation in animals with SI for 9.57 +/- 3.27 minutes in the peritrauma period eliminated mortality (p < 0.05, intubated vs. nonintubated). Histologically, after SI, there was diffuse edema throughout the corpus callosum below the region of injury and in the thalami. Other injuries included neuronal death in the deep nuclei, bilateral disruption of CA3, diffuse subarachnoid hemorrhage, and, in some, ventriculomegaly. Following a diffuse TBI in immature rats, SI produced a mortality rate, neurological deficit, and histological changes similar to those previously reported for an injury resulting from a 450-g weight dropped from 2 m in adult rats. A graded insult was achieved by maintaining the height of the weight drop but varying the weights. Weight loss, acute physiological instability, and acute neurological deficits were also indicative of an SI. Mortality was eliminated when ventilatory support was used during the peritrauma period. This model should be useful in studying the response of the immature rat to diffuse severe TBI.

Animals↗
PubMed1996

Secondary amenorrhea due to hydrocephalus treated with endoscopic ventriculocisternostomy. Case report.

The authors present a case of secondary amenorrhea in a 32-year-old woman found to have noncommunicating hydrocephalus due to aqueductal stenosis. Although the presentation of hydrocephalus with amenorrhea has been previously reported, this association remains rare. After treatment via endoscopic third ventriculocisternostomy, the patient resumed normal menstruation and all hormonal abnormalities have resolved except hypothyroidism. A review of the literature on the etiology of endocrinological disturbances in patients with hydrocephalus is presented.

Adult↗
PubMed1995

Development of a crossed corticotectal pathway following cerebral hemispherectomy in cats: a quantitative study of the projecting neurons.

A hypothetical mechanism for the partial sparing of visual function in the contralateral visual field following cerebral hemispherectomy early in life is the formation of a new corticotectal pathway arising from the remaining primary visual cortex (areas 17 and 18) that projects to the contralateral superior colliculus. To test this hypothesis, the left superior colliculus of intact adult and neonatal (5-15 days old) cats and of adult cats with a left cerebral hemispherectomy sustained neonatally (7-9 days old) or in adulthood, was injected with WGA-HRP and the brains were processed for combined TMB/DAB histochemistry. The primary visual cortex was examined, labelled neurons were counted and the cross sectional area of their somata was measured. The left primary visual cortex of intact adult animals exhibited a mean of 959.68 labelled cells +/- 406.5 (S.E.), with a mean soma size of 366.7 microns2 +/- 131.2. For the neonatal intact cats, there was a mean of 75.31 +/- 21.08 cells within the left primary visual cortex which exhibited a mean soma size of 249.56 microns2 +/- 68.18. The peak cell size distribution for both intact groups was similar at 300 microns2. Virtually no labelled neurons were detected in the right primary visual cortex of intact animals (neonatal or adult). For neonatal-hemispherectomized cats, the remaining right primary visual cortex exhibited a mean cell count of 351.09 +/- 126.3 cells, with a mean soma size of 436.1 microns2 +/- 131.5, and a peak cell size distribution of 400 microns2. Finally, for adult-hemispherectomized animals, the contralateral primary visual cortex exhibited 68.27 +/- 20.13 neurons having a mean soma size of 486.6 microns2 +/- 143.2 with a peak cell size distribution of 500 microns2. These results indicate that reorganization of the corticotectal pathway occurs in both adult- and neonatal-hemispherectomized cats but is more pronounced in neonatal-lesioned animals. In addition, the cells of origin of this reorganized pathway tended to be larger, perhaps in response to a greater axonal arborization.

Animals↗
PubMed1995

The role of frameless stereotactic techniques in the treatment of pediatric CNS lesions.

The surgical management of children with deep-seated lesions within the brain and skull base or with superficial lesions within functionally important regions of the brain is often challenging. In order to optimize the functional outcome of an affected child, it is essential not only to adequately treat the offending lesion, but also to minimize injury to the surrounding brain. In this study, we examined the applicability of a video-interactive frameless stereotactic system for intraoperative localization and treatment of a variety of pediatric central nervous system problems, including craniotomy for tumor (n = 14), vascular malformation (n = 3), or cortical resection for intractable epilepsy (n = 4); ventricular puncture for shunt insertion in a patient with slit ventricles (n = 2); transoral odontoid resection (n = 1); cannulation of a brainstem syrinx (n = 1); removal of a foreign body (n = 1); and posterior craniocervical decompression (n = 1). The efficacy of the system was judged on several criteria: (1) the accuracy of the targeting achieved; (2) whether the system facilitated treatment of the lesions of interest; and (3) whether neurologic function was preserved. In general, the accuracy of the system for target localization was within 2-4 mm when rigid head fixation was employed intraoperatively. In such cases, frameless stereotactic guidance was extremely helpful in providing rapid and reliable assistance with operative planning, which facilitated the treatment of a variety of lesions in critical areas of brain with minimal neurologic morbidity. Limitations of this technology and potential solutions to these shortcomings are discussed. We conclude that the application of frameless stereotaxis for intraoperative localization represents a major advance in the treatment of a variety of intracranial processes in children by providing a means for accurately directing the approach to and removal of a targeted lesion while minimizing injury to the surrounding brain.

Astrocytoma↗
PubMed1995

Use of subdural grids and strip electrodes to identify a seizure focus in children.

For patients with intractable seizures, the best surgical outcome is achieved following precise localization of the seizure focus. Scalp EEG monitoring may be insufficient and chronic subdural invasive EEG monitoring has therefore been advocated. At Children's Hospital in Boston, 31 children had chronic subdural monitoring from January 1990 through June 1994. The average age at implantation was 11 years. Most patients (22) had placement of grid electrodes combined with strip electrodes to map temporal and/or frontal regions bilaterally. Twenty of the patients eventually had a resective procedure based on the findings. During monitoring, cortical stimulations were performed to localize speech and somatosensory areas. There was only one complication, a subdural hematoma in a patient who had had previous surgery. Chronic subdural EEG monitoring is helpful in precisely localizing seizure foci in pediatric patients; it also allows motor and speech mapping and appears to be a safe modality in children.

Adolescent↗
PubMed1995

Pial synangiosis for moyamoya syndrome in children.

The authors describe a modification of the encephalo-duro-arterio-synangiosis (EDAS) surgical technique for patients with moyamoya syndrome in which the arachnoid is widely opened over the exposed brain and the donor superficial temporal artery adventitia is sutured directly to the pia with 10-O nylon suture ('pial synangiosis'). The procedure has been performed in 34 patients over a 10-year period, with follow-up arteriograms 1 year following the procedure demonstrating markedly enhanced middle cerebral artery flow through the surgical site. Operative morbidity has been limited to two postoperative strokes, both in patients who were neurologically unstable preoperatively; and the clinical stability of the operated patients has thus far been excellent.

Adolescent↗
PubMed1995

Chronic invasive monitoring for identifying seizure foci in children.

In both children and adults, it has been well established that the precise localization of a seizure focus allows for the best possible resection and outcome. Long-term invasive monitoring with DE has been the most widely used modality to evaluate patients with intractable seizures of temporal lobe origin. The study of epilepsy in children, however, requires assessment of the cause of the seizures with a resultant decision regarding the optimal modality of study for the particular problem. Complex partial seizures of medial temporal lobe origin without clear concordance or lateralizing information are best studied using DE. With MR imaging anatomic localization, stereotactic insertion of DE can be performed accurately and relatively safely. The information obtained permits lateralization and focus localization if the lesion is within the medial structures. The ability of DE to study epilepsy outside of the medial temporal lobe, however, is suboptimal. Many centers have used surface electrodes to map temporal lobe foci successfully. SE and SGE have not been widely used in children. Subdural electrode arrays, however, are superior to DE in extratemporal epilepsy because the cortical surface contacts provide the best recordings of epileptiform activity from a wide range of extratemporal regions. The limitations of intraoperative ECoG in the awake child are well understood. It is rare that a child can undergo surgery under local anesthesia and cooperate to the extent necessary for definitive mapping of the seizure focus and eloquent areas. Thus, invasive long-term monitoring would seem ideal in the epileptic pediatric patient because it allows for a more relaxed pace in which to record events, and because of the indwelling nature of these electrodes, it is possible for the investigator to map eloquent areas of the brain before resection. This type of evaluation completely and accurately maps interictal and ictal activity, and through cortical stimulation or mapping of somatosensory areas by evoked potentials, eloquent areas of the brain, such as motor and speech regions, can be identified. This method is limited to older children because the young child often has inadequate cortical development to localize these areas definitively. One should note that in young children (under the age of 4 years), the absence of a response to standard cortical stimulation does not indicate nonfunctional cortex. Long-term intractable seizures and significant antiepileptic drug requirements may contribute to developmental and psychosocial deficiencies in the epileptic patient.(ABSTRACT TRUNCATED AT 400 WORDS)

Child↗
PubMed1995

Temporal lobe resections in children.

Often, seizures in childhood are intractable to medical therapy. Intractable seizures and prolonged anticonvulsant medication can adversely affect intellectual development and psychosocial maturation in children. Temporal lobe resections for complex partial seizures and focal epilepsy in children can be performed with minimal morbidity. The higher morbidity lies with prolonged observation of these children with intractable seizures. The final result of surgical treatment shows that children can significantly benefit from an early developmental period without anticonvulsant medication or intractable seizures with improvements in both IQ and behavioral interactions. With improvements in neuroimaging techniques and evaluation procedures, more children can be identified who might benefit from a resective procedure. It is thus advocated that early evaluation and surgical intervention be performed to gain improvement in seizure control and psychosocial development.

Adolescent↗
PubMed1995

The future of pediatric epilepsy surgery. Signposts and science.

Many of the advances in pediatric epilepsy surgery should reflect scientific, technical, and conceptual issues identical to those seen with adult epilepsy surgery. However, there are certainly some unique issues involving the developing brain, and these aspects require significant input from the discipline of developmental neurobiology and the study of cortical plasticity. These developmental disciplines may prove as critical as more traditional areas of electrophysiology thought to be key to the advancement of epilepsy surgery. Pediatric epilepsy surgery may turn out to be the major beneficiary of the basic scientific advancements in these burgeoning fields.

Adolescent↗