Search PubMed⌕ Search

Biomedical subjects

Harold L Rekate

Publications and source records attributed to Harold L Rekate.

At least 37 records · Page 2Linked to original sources
PubMed2005

Microsurgical anatomy of the transcallosal anterior interforniceal approach to the third ventricle.

OBJECTIVE: We explored relevant regional microanatomy as it relates to the challenging anterior interforniceal (AIF) approach for removing hypothalamic hamartomas. METHODS: Five silicone-injected cadaveric heads were dissected by use of frameless stereotactic navigation to reveal microanatomy and extent of exposure through the transcallosal AIF approach. Distances between trajectories to the coronal suture and the genu of the corpus callosum (CC) and between the posterior border of the anterior commissure to the lower end of the rostrum of the CC and posterior border of the foramen of Monro were measured. RESULTS: The AIF approach provided adequate access to the anterior third ventricle and related structures (i.e., hypothalamus, infundibular recess, and mamillary bodies) through the corridor bounded by the anterior commissure anteriorly and the choroid plexus at the foramen of Monro posteriorly. The mean distances from the posterior trajectory to the coronal suture and the genu of the CC were 44.8 mm (range, 43.8-46.2 mm) and 14.88 mm (14.1-15.7 mm), respectively. The mean distance from the anterior trajectory posterior to the coronal suture was 4.66 mm (0-8.9 mm), and 32.6 mm (30.5-33.9 mm) to the genu of the CC. The mean length of callosotomy was 17.52 mm (16.2-19.1 mm). The mean distance between the posterior border of the anterior commissure and the lower end of the rostrum of the CC was 5.22 mm (4.6-5.6 mm), and 10.52 mm (9.7-11.5 mm) to the posterior border of the foramen of Monro. CONCLUSION: The technically safe AIF approach permitted limited interforniceal splitting, no major deep vein manipulation, and adequate visualization of the hypothalamus, infundibular recess, and mamillary bodies.

Cadaver↗
PubMed2005

Successful resection of a hypothalamic hamartoma and a Rathke cleft cyst. Case report.

The authors report the case of a 12-year-old girl with Pallister-Hall syndrome, long-standing refractory, symptomatic epilepsy, mental retardation, and panhypopituitarism in whom two rare, deep midline lesions were detected. She underwent successful transsphenoidal resection of the Rathke cleft cyst and transcallosal resection of the hypothalamic hamartoma within a 4-day period without complications. Neuropathological studies confirmed the neuroimaging diagnoses for the two lesions. The patient has been seizure free for 6 months postoperatively.

Central Nervous System Cysts↗
PubMed2005

Craniopharyngioma.

Explore the source record for details and available documents.

Craniopharyngioma↗
PubMed2005

Surgical strategies for approaching hypothalamic hamartomas causing gelastic seizures in the pediatric population: transventricular compared with skull base approaches.

OBJECT: The authors provide evidence that direct resection of hypothalamic hamartomas (HHs) can improve associated gelastic and nongelastic seizures. METHODS: Ten children younger than 17 years of age underwent resection of HHs (nine sessile and one pedunculated) that were causing refractory epilepsy. Lesions were approached from above transventricularly through a transcallosal anterior interforniceal approach in six cases, endoscopically through the foramen of Monro in one, and from below with a frontotemporal craniotomy including an orbitozygomatic osteotomy in three. Medical charts were reviewed retrospectively, and follow-up data were obtained through office records and phone calls. Follow-up periods ranged between 12 and 84 months (mean 16.8 months). All patients in whom the approach was from above had sessile HHs. Five were free from seizures at follow up and two had a reduction in seizures of at least 95%. The transventricular route allowed excellent exposure and visualization of the local structures during resection. Among the three patients in whom the approach was from below, one became free of seizure after two procedures and one had a 75% reduction in epilepsy; the latter two had sessile HHs. The exposure was inadequate, and critical tissue borders were not readily apparent. Although the HH was adequately exposed and resected, the epilepsy persisted in the third patient, who had a pedunculated lesion. The overall rate of major permanent hypothalamic complications appeared to be slightly lower for the orbitozygomatic osteotomy group. CONCLUSIONS: Sessile lesions are best approached from above. Approaches from below adequately expose pedunculated hamartomas. The likelihood of curing seizures seems to be higher when lesions are approached from above rather than from below.

Cerebral Ventricles↗
PubMed2004

Management of hydrocephalus in posterior fossa tumors: how, what, when?

OBJECT: The aim of this work is to analyze the current management of hydrocephalus associated with posterior fossa (PF) tumors. METHODS: The personal perspectives of experienced pediatric neurosurgeons were presented at a virtual round table. DISCUSSION: Preoperative hydrocephalus has been reported in about 80% of patients with PF tumors and postoperative treatment is required for persistent or progressive hydrocephalus in about 25-30% of the cases. Preoperative management includes external ventricular drainage (EVD), endoscopic third ventriculostomy (ETV), shunt insertion, and no treatment at all, while ETV and ventriculo-peritoneal (V-P) shunt are recommended as treatment after PF craniotomy. CONCLUSION: There is no consensus on the way hydrocephalus should be managed before, during, and after PF surgery. While awaiting prospective multicenter trials of various management schemes the perioperative management of hydrocephalus in the context of posterior fossa tumors should be considered as options.

Attitude of Health Personnel↗
PubMed2004

The effects of craniosynostosis on the brain with respect to intracranial pressure.

Intracranial pressure (ICP) and skull volume are intricately related. Craniosynostosis alters skull volume, and the many forms of craniosynostosis complicate the relationship to ICP even further. Patients with single-suture synostosis are less likely to experience elevated ICP than patients in whom multiple sutures, craniofacial syndromes, or both are involved. Among patients with more than one suture involved, the multifactorial mechanisms underlying elevated ICP include cephalocranial disproportion and venous outflow obstruction. Direct monitoring of ICP for at least 24 hours can aid in the diagnosis and decision making process. The management of craniosynostotic patients is diverse and necessitates a long-term plan for follow-up.

Brain↗
PubMed2004

Cognitive impact of craniosynostosis.

This article reviews the data on the effects of synostosis on cognitive development and the role of surgical intervention in ameliorating these effects. The literature on children with single-suture craniosynostosis, treated both surgically and conservatively, is reviewed. The evidence for possible pathophysiological mechanisms by which brain restriction might affect cognitive development is also reviewed. Although children with single-suture isolated craniosynostosis may be at risk of developmental delay, learning disability, or both, especially with regard to speech or language skills, available testing methodologies provide no evidence of an association between surgical intervention and ultimate intellectual outcome. Despite the controversies about the role of surgery in addressing the cognitive sequelae of simple craniosynostosis, in the absence of definitive data, the indications for surgery include correction of deformity and minimization of cognitive sequelae. The relative risks of performing surgery early or late must be determined on an individual basis, balancing potential cosmetic and cognitive benefits against the heightened risk of reoperation or perioperative morbidity.

Child↗
PubMed2004

Selecting patients for endoscopic third ventriculostomy.

ETV using contemporary instrumentation has been used for more than 50 years, but its use has become widespread only in the last 10 to 15 years. Randomized prospective trials comparing ETV with shunts are needed before definitive statements can be made about the role of the former in managing the many forms of hydrocephalus. The absolute and relative contraindications for the use of ETV in the management of hydrocephalus are shown in the Box 1 on this page. It is important not to presume that a specific radiographic or clinical feature would prevent a patient from responding to this rather new procedure without testing the hypothesis. Patients should be given as much information as possible regarding the risks and benefits of ETV so they can participate in the decision-making process. When should the role of ETV in the management of hydrocephalus be discussed with a patient? At the initial diagnosis of hydrocephalus, the patient or family should be informed of this potential alternative to shunting for the management of hydrocephalus. I also believe that patients with working shunts who are being followed chronically should be informed about ETV as a potential treatment option when their shunt fails. Every shunt failure or infection should be viewed as an opportunity to explore the possibility that the patient could become shunt independent.

Cerebral Ventricles↗
PubMed2004

Treatment of refractory status epilepticus with hemispherectomy.

A 7-year-old boy with left hemiparesis secondary to right hemispheric cortical dysplasia was admitted to the hospital with increasing numbers of seizures. Magnetic resonance imaging showed a small dysplastic right hemisphere with abnormally thickened gyri and an apparently normal left hemisphere. Previous video-electroencephalogram (EEG) monitoring showed bilateral independent spikes and generalized slow spike-and-wave episodes on EEG and [18F]fluorodeoxyglucose (FDG) positron emission tomography scan demonstrated scattered areas of regional hypometabolism bilaterally; therefore hemispherectomy was not undertaken at that time. During this hospital stay, nonconvulsive status epilepticus developed and was refractory to multiple medical therapies including pentobarbital (PTB) coma. Burst-suppression pattern during PTB coma appeared to be generalized spike and wave, but when EEG was reviewed with increased time resolution spikes suggested a right hemisphere origin. The patient underwent bilateral intracarotid amobarbital spike-suppression test that showed only minimal suppression of epileptiform discharges with injection of the left carotid, but complete suppression of spike activity after right-sided carotid injection. A right hemispherectomy was performed with complete cessation of status epilepticus. Postoperative EEG showed no epileptiform discharges. Patient follow-up was limited to 12 months after surgery. The patient had regained the ability to walk unaided and was seizure free with a single antiepileptic medication. This case illustrates a potentially life-saving procedure for refractory status epilepticus and several techniques including a spike-suppression test to aid in prediction of cessation of seizures after hemispherectomy.

Amobarbital↗
PubMed2004

Diagnosis and management of pineocytomas.

OBJECTIVE: Pineocytomas are associated with the most favorable prognosis of all pineal tumors. However, a subset of pineocytomas may have a predilection for recurrence and therefore behave aggressively. PATIENTS AND METHODS: Records of nine patients (five men, four women; mean age, 44 yr; range, 24-63 yr) with histologically diagnosed pineocytomas consecutively treated between 1990 and 2003 were reviewed retrospectively to identify factors predictive of aggressiveness. Eight patients presented with hydrocephalus and four with tectal compression. Three patients underwent gross total resection, and six underwent subtotal resection or biopsy. RESULTS: Three local recurrences necessitated reoperation. One recurrence involved the obex of the fourth ventricle. The mean time to recurrence was 3.5 years (range, 1-7 yr). There was no correlation between histological features and tumor recurrence. Patients undergoing radiosurgery showed stable or attenuated local disease (mean follow-up, 19.3 mo; range, 6-36 mo). Mean radiographic follow-up was 34 months (range, 6 mo to 10 yr). Mean clinical follow-up was 36 months (range, 1 mo to 10 yr). CONCLUSION: A subset of pineocytomas demonstrates the potential for symptomatic recurrence. We advocate an attempt at gross total tumor resection for all symptomatic patients with tectal plate compression, reserving radiosurgery for small, subtotally resected, or recurrent lesions. Patients must be followed closely for recurrence. Radiosurgery seems to be beneficial for local tumor control. Further investigation is needed to identify histological markers for pineocytomas that behave aggressively.

Adult↗
PubMed2004

Resolution of pseudotumor cerebri after bariatric surgery for related obesity. Case report.

Two obese women, both of whom were 42 years of age, were examined for pseudotumor cerebri. Intracranial venography revealed increased pressure in the dural venous sinuses and the right atrium. The increased right atrial pressure was attributable to the patients' obesity. Both patients underwent bariatric surgery to achieve weight loss. Approximately 1 year later, a clinical evaluation showed that in both women the pseudotumor cerebri had resolved. Repeated measurements of dural venous pressure indicated that the patients' pressures had returned to normal. Obese patients with pseudotumor cerebri and stable visual symptoms are best treated with weight loss to avoid shunt placement or optic nerve sheath fenestration.

Adult↗
PubMed2004

Nonsurgical treatment of a C6-7 unilateral locked facet joint in an infant. Case report.

Cervical spine injuries in the pediatric population typically affect the upper cervical region. The authors present the first reported case of a subaxial C6-7 unilateral locked facet joint in a neurologically intact 10-month-old infant. To date, this patient's nonoperative treatment has been successful. The proposed biomechanical mechanism of this injury and the treatment paradigm are discussed.

Cervical Vertebrae↗
PubMed2004

Treatment of basilar invagination associated with Chiari I malformations in the pediatric population: cervical reduction and posterior occipitocervical fusion.

OBJECT: The reduction of basilar invagination associated with Chiari I malformations in pediatric patients is often possible. Eleven children ranging in age from 1.5 to 17 years underwent a novel treatment method involving decompression, manual reduction, and posterior instrumentation-augmented fusion. Outcomes were evaluated retrospectively. METHODS: After decompression of the lesion, manual craniocervical distraction and extension were performed, followed by posterior occipitocervical fusion involving rigid internal fixation. All patients were symptomatic at presentation. Intraoperative monitoring included somatosensory evoked potentials, fluoroscopy, and direct intradural demonstration of the craniocervical junction. No new neurological deficits occurred immediately after surgery. Perioperatively, symptoms in seven patients improved significantly and in four they remained unchanged. Three patients required subsequent transoral resections. During long-term follow up (mean 39.4 months, range 3-92 months) symptoms improved markedly in nine, remained unchanged in one, and progressively worsened in one patient. CONCLUSIONS: In selected cases, manual cervical distraction and extension, posterior fixation, and fusion appear to provide a safe, effective standalone treatment for basilar invagination associated with Chiari malformation in children.

Adolescent↗
PubMed2004

High cervical disc herniation presenting with C-2 radiculopathy. Case report and review of the literature.

The authors report the case of a 78-year-old man with a C2-3 disc herniation that had migrated rostrally, causing C-2 radiculopathy. The C-2 radiculopathy manifested immediately after the patient underwent placement of a ventriculoperitoneal shunt for normal-pressure hydrocephalus. Myelography and computerized tomography scanning of the cervical spine revealed an extradural lesion anterolateral to the thecal sac eccentric to the right. The patient underwent a C1-3 laminectomy, C-2 nerve root decompression, and excision of the lesion. Postoperatively the patient's radiculopathy resolved completely. To the authors' knowledge, this is the first case of a C2-3 disc herniation manifesting as C-2 radiculopathy and treated via a posterior extradural approach.

Aged↗
PubMed2003

Lumboperitoneal shunts in children.

OBJECTIVE: To determine the safety and efficacy of lumboperitoneal (LP) shunts in carefully selected children with abnormalities of the absorption of cerebrospinal fluid. METHODS: Magnetic resonance imaging studies, indications for treatment and pre- and postoperative symptoms of 25 patients (mean age 9.6 years) who had undergone LP shunting in the past 10 years in a single pediatric neurosurgical practice were analyzed retrospectively. RESULTS: Indications for treatment included postoperative pseudomeningocele, pseudotumor cerebri and a severe form of slit ventricle syndrome. Preoperative symptoms resolved completely in all 25 patients as a result of the shunt, and no patient developed symptomatic or radiographic hindbrain herniation. Twenty-one shunts incorporated valve mechanisms. CONCLUSION: LP shunts may be used for specific indications without excessive risk of hindbrain herniation.

Adolescent↗