Surgical treatment of benign intracranial hypertension--subtemporal decompression revisited.

BACKGROUND: Subtemporal decompression, first advocated by Dandy for the treatment of benign intracranial hypertension or pseudotumor cerebri, has been replaced as a treatment mainstay by medical management using diuretics, steroids, and lumbar puncture. Failure of these forms of treatment has frequently led to insertion of cerebrospinal fluid shunts. METHODS: We have retrospectively reviewed the long term outcome of eight patients who were treated by subtemporal decompression (STD) for classical presentations of refractory benign intracranial hypertension. The follow-up period ranged from 8 to 26 years. RESULTS: Within 1 month of STD, deterioration in visual fields and acuity resolved in all eight patients. Five of eight patients required CSF diversion procedures after subtemporal decompression to control headaches. No patient experienced recurrent permanent visual deterioration after STD. CONCLUSION: STD may be the most effective treatment in both long and short term follow-up to provide lasting relief and prevention of visual morbidity caused by refractory benign intracranial hypertension.

Lumbar lordosis measurement. A new method versus Cobb technique.

STUDY DESIGN: A historic cross-sectional study of lumbar lordosis in 199 healthy individuals aged 1-30 years. OBJECTIVE: To evaluate the magnitude and rate of the development of the normal lumbar lordotic curve with age using two methods of measurement. SUMMARY OF BACKGROUND DATA: There is no agreement among spine physicians on the range of the normal lumbar lordotic curve. In certain conditions, such as a tethered spinal cord, a change in lordotic curve may indicate or even precede the onset of neurologic symptoms. Reliable measurements of the lumbar lordotic curve may aid in the early diagnosis and management of these conditions, before irreversible neurologic change ensues. METHODS: The lumbar lordotic curve was measured by the traditional Cobb technique and by a newly designed method, tangential radiologic assessment of lumbar lordosis. The data were subjected to the Morgan-Pitman test for correlated variances to observe which of the two methods was more reliable in measuring the magnitude and rate of change in the lumbar lordotic curve. RESULTS AND CONCLUSIONS: The rate of development of the lumbar lordotic curve appears to be nonlinear, increases during first year of life and during puberty, and reaches a plateau of approximately 50 degrees at maturity. The tangential radiologic assessment of lumbar lordosis method is more reproducible and more reliable in the lumbar lordotic curve, providing a smaller range of normal values (8 degrees-16 degrees less) than the Cobb method.

Multiple cavernous angiomas after high-dose whole-brain radiation therapy.

Modern neuroimaging techniques have led to increased identification of angiographically occult cerebral angiomatous malformations. Cavernous angiomas or cavernomas account for approximately 16% of all cerebrovascular malformations. Little is reported about the etiology or risk for acquiring these lesions. This report suggests a possible association between acquired intracranial vascular malformations and long-term survivors after craniospinal external beam radiation therapy indicating that greater understanding of the cerebral vascular system's response to injury may provide insight into the evolution and progression of these lesions.

A closer look at the ventriculo-gallbladder shunt for the treatment of hydrocephalus.

Six patients with hydrocephalus who were treated with cerebrospinal fluid (CSF) shunts became refractory to serosal absorption of CSF. All were subsequently treated with ventriculo-gallbladder shunts. The surgical technique and long-term results were evaluated by retrospective review of the hospital records. Detailed evaluation of 1 of the 6 has suggested a dynamic role for the gallbladder in the function of ventriculo-gallbladder shunts.

Growth hormone treatment of children with neural tube defects: results from 6 months to 6 years.

OBJECTIVE: Patients with neural tube defects (myelomeningocele) have severe growth retardation, and treatment with recombinant human growth hormone (rHGH) for 6 months accelerates growth velocity. We examined patients treated for longer periods to determine whether accelerated growth persists, and whether patients demonstrated to be growth hormone deficient have a greater response to rHGH therapy. METHODS: We retrospectively evaluated the growth rate and length standard deviation score (SDS) of 22 patients in response to treatment with 0.3 mg/kg per week of rHGH for 7 to 72 months. Nine of 22 patients were growth hormone deficient (nocturnal and provocative growth hormone responses < 7 ng/ml). Treatment success was defined as an increase of length SDS of > 0.2 SD per year. RESULTS: Fourteen patients (64%) had treatment successes, and eight had treatment failures. Length SDS improved from a pretreatment value of -2.9 (+/- 1.2) to the most recent length SDS of -1.9 (+/- 1.4) (p < 0.001). The growth rate was significantly increased through year 4 of treatment. The annualized growth rate after 6 months of rHGH treatment was significantly different for the success and failure groups (11.0 +/- 2.6 cm/yr vs 5.1 +/- 3 cm/yr, p < 0.001). The annualized 6-month growth rate during treatment was related to the probability of treatment success. CONCLUSION: Treatment with rHGH significantly improves the growth rate and length SDS of children with neural tube defects. The 6-month annualized growth velocity during treatment was predictive of long-term treatment response. The effect on adult stature is unknown.

Growth of growth hormone-treated and nontreated children before and after tethered spinal cord release.

Children with myelomeningocele (MM) are very short and respond to treatment with recombinant human growth hormone (RHGH) with an acceleration in growth. Following primary closure of the MM, a tethered spinal cord may produce neurologic and orthopedic deformities. We compared the short-term growth rate and length standard deviation score (L-SDS) for stature of 13 prepubertal children with MM (7 males, 6 females, mean age 6.1 +/- 2.5 years) before and after symptomatic tethered spinal cord release (TCR) to an untreated asymptomatic matched control group. We also compared these data to 7 prepubertal children with MM and growth hormone inadequacy who had TCR and were then treated with RHGH. TCR significantly increased the growth rate compared with matched controls (p < 0.01); however, TCR and RHGH in combination provided an increased gain in growth rate and L-SDS over TCR alone (p < 0.01). Tethered spinal cord influences the growth rate of children with MM. Further study is necessary to evaluate the relationship of the tethered spinal cord to growth and treatment of growth failure.

Adult stature and anthropomorphic measurements of patients with myelomeningocele.

UNLABELLED: Children with myelomeningocele are extremely short, yet little data exists on adult stature and anthropomorphic measurements. We measured the recumbent length, weight, arm length, sitting height and calculated body mass index of 54 adults with myelomeningocele. Mid parental height was also calculated. Measurements were compared with normative data. Patient charts were reviewed for history of hydrocephalus. The 27 males and 27 females had a mean age of 24.8 +/- 5.7 years. The mean length for adult females was 141.9 +/- 12 cm and was 152.1 +/- 13 cm for males. Patients with thoracic level of lesions were shorter than those with lumbar level who were, in turn, shorter than those with sacral levels. Recumbent length, sitting height, arm length and arm span were significantly smaller than expected values. Recumbent length was smaller than mid parental height. Those with ventriculoperitoneal shunts, required for hydrocephalus, were shorter than these without a shunt. CONCLUSION: Adults with myelomeningocele have significant short stature. Arm span is not an interchangeable measure with length for patients with myelomeningocele. Multiple factors are likely to be responsible for the observed short stature.

The editors' labours: separating the wheat from the chaff.

From the author's standpoint, the editor is viewed as 'one who separates the wheat from the chaff and then prints the chaff'! Since its inception, Pediatric Neurosurgery has tried to provide the reader with the guarantee that only the 'wheat' is published. This paper will examine the policies of the journal's Editorial Board and in particular outline the review process for submitted manuscripts. In addition to certain operational items, the paper will consider how the 'peer' in 'peer review' is identified, the grading instruments for paper acceptance, the likelihood that the readers and peer reviewers agree on manuscript quality, and how authors should view failure. The Society is firmly committed to our journal. Our individual responsibilities begin with paper preparation and then its presentation at the annual meeting. Thereafter, it is important for the membership to appreciate that their participation, as either author and/or reviewer, is critical for the continued success of our journal.

Change in spinal curvature following release of tethered spinal cord associated with spina bifida.

Changes in spinal curvature, scoliosis, kyphosis and lordosis are associated with the growth of patients with myelomeningocele. Previous investigators have stated that progressive developmental scoliosis is related to tethered spinal cord. In order to investigate the relationship of tethered spinal cord release to progression of spinal curvature, we surveyed the medical records of 262 patients with a history of one or more tethered spinal cord release. For 216 of these patients, a total of 2,369 serial spine x-rays, obtained over a 20-year period, were reviewed by the standard Cobb method for progression of scoliosis, thoracic kyphosis and lordosis. In addition, the serial spine x-rays of 74 patients without clinical findings of tethered spinal cord were collected and reviewed for comparison of progressive scoliosis and kyphosis. One hundred and sixty normal lumbar x-rays were evaluated to compare the progression of the lordotic curve in patients with tethered cord release with a normal population. Progression of scoliosis plateaued or declined following release of tethered cord in patients with lumbar and sacral level lesions, however, tether release did not halt the progression of scoliosis in the thoracic level group. Tethered cord release altered the course of lordosis in L1 through L3 level lesions, but had little affect on the normal progression of lordosis in patients with L4, L5 or sacral level lesions. Finally, tethered spinal cord release appears to be associated with a decrease in the incidence and magnitude of kyphosis.

A pilot investigation of poloxamer 407 for the prevention of leptomeningeal adhesions in the rabbit.

Leptomeningeal adhesion formation frequently complicates operations and diseases of the central nervous system. Chronic adhesive arachnoiditis may follow intraspinal surgery for disc, tumor, and closure of myelomeningocele, eventually producing pain and declining neurological status of the patient. Reoperation for scar removal is seldom successful as the arachnoidal adhesions reform. Poloxamer 407 (P407) has been shown to reduce postoperative peritoneal adhesion formation in rats and golden hamsters. In a rabbit model, we investigated the potential of P407 to prevent the production of arachnoidal adhesions and nerve root scarring following laminectomy and surgical meningeal injury. The lumbar spinal roots of 8 New Zealand white rabbits were surgically isolated under magnification. One root sleeve axilla was opened and immediately closed with 10-0 suture (control site) and a second root sleeve axilla was opened, P407 injected, and closed with 10-0 suture (treatment site). Five of 7 rabbits treated with P407 and followed for 7-42 days showed no arachnoidal adhesions at the level of the nerve root. Four New Zealand white rabbits had the lamina removed, and the dura over the spinal cord was opened at two sites separated by one to two lumbar segments. At one site P407 was inserted beneath the dura following durotomy, and the other site was opened in a similar fashion and immediately closed without the insertion of P407. There was a 50% reduction in leptomeningeal adhesion formation with the use of P407. P407 may be useful in neurosurgery for the prevention of arachnoidal adhesions.

Cerebrospinal fluid shunt infections. Report of 41 cases and a critical review of the literature.

All shunt procedures performed at our institution from July 1982 to December 1987 were analyzed for factors possibly related to shunt infection. There were 41 infections detected in 31 patients for an overall rate of 6.9%. Only intraventricular hemorrhage (IVH) as an etiology of the hydrocephalus and internalization of an external ventricular drain (EVD) were found to correlate with septic risk. An extensive review of all the English language literature concerning shunt infections over the last 15 years was undertaken. Little consensus could be found among the 35 publications in regard to factors predisposing to shunt sepsis. Even the issue of antibiotic prophylaxis remains clouded as all papers examined exhibited methodologic flaws.

CSF polyamines in childhood.

Specimens of CSF from 76 children without neurologic disease and from 191 children with neurosurgical conditions were assayed for polyamine content. Putrescine and spermidine concentrations decreased with age. In children with intracranial tumors, polyamine concentrations in lumbar CSF were comparable with those in ventricular CSF. Putrescine level was significantly increased in children with medulloblastomas. Spermidine level was increased in children with medulloblastomas, glioblastomas, and astrocytomas. Concentrations of putrescine and spermidine were significantly increased in infants with myelomeningocele and hydrocephalus. Spermidine concentrations were significantly increased in older children with myelomeningocele, encephalocele, and hydrocephalus. Polyamines thus seem to be increased by rapid cell proliferation and by disorders affecting myelination. Since putrescine and spermidine concentrations may be of use in monitoring tumor progression, the effects of childhood growth and of hydrocephalus must be considered for children whose brain tumors are associated with hydrocephalus.

Detection of neonatal intraventricular hemorrhage using transcephalic impedance.

Transcephalic impedance (the resistance of the head to the flow of a 100 mu-amp alternating current) was measured serially during the first eight days of life in 93 neonates, ranging in gestational age from 26 to 43 weeks. Data compiled from the 70 clinically normal neonates showed an increase in mean trancephalic value with gestational age; this mean increase did not exceed 2.5 ohms during the first eight days of life within any four-week gestational age-group. Seven of the 23 clinically abnormal neonates showed evidence of clinical deterioration typical of intraventricular hemorrhage, and this diagnosis was confirmed at autopsy. Transcephalic impedance for these patients increased considerably with the onset of clinical deterioration, while the impedance for 11 clinically normal neonates, matched with these seven for gestational age, postnatal age and time of impedance measurement, rose only slightly. Transcephalic impedance is an uncomplicated, non-invasive, inexpensive test which has potential as a diagnostic aid in the detection of intraventricular hemorrhage.

The value of myelography in the management of childhood medulloblastoma.

Sixteen children with newly diagnosed medulloblastomas underwent myelography prior to radiotherapy. None had clinical evidence suggesting spinal cord involvement. Seven patients (43%) were discovered to have unsuspected metastases involving the cord. Cerebrospinal fluid (CSF) cytology results were inaccurate in predicting spinal cord involvement. Additional radiation was administered to the demonstrated lesions. Thirteen children (81%) are alive and well 7-53 months (average 26) from completion of therapy. One of nine children with a normal myelogram initially, and two of seven with initial spinal cord involvement have relapsed.

Tethered spinal cord following meningomyelocele repair.

Of 16 consecutive patients with tethered spinal cord studied, most had undergone repair of a meningomyelocele. All were evaluated using somatosensory evoked potentials at 6 to 12-month intervals. Other possibilities include tethered filum terminale, lipomeningocele, membrana reuniens, and miscellaneous conditions (diastematomyelia, neurenteric cysts, etc.). Metrizamide myelography with polytomography was superior to gas myelography in showing a low-lying cord, obtuse nerve root angles, and a thin subarachnoid space between the cord and the dorsal meninges cephalad to the tether. Surgery is generally helpful in these patients.

Posterior lumbar apophyseal fractures.

The radiographic findings in 4 patients with fractures of the lumbar vertebral ring apophysis are reported. All patients had a bony ridge or fragment projecting into the spinal canal, usually from the lower border of L4; a defect in the postero-inferior aspect of the vertebral body; and either an anterior extradural impression or complete blockage on the myelogram. Computed tomography was performed on one patient and appears to be helpful in demonstrating bone within the spinal canal. Preoperative diagnosis can facilitate selection of the appropriate surgical approach.

Biopsy of pediatric brain stem tumors.

26 patients, average age of 7.3 years, has biopsies of a brain stem tumor. 62% of the patients presented with hydrocephalus, and ventriculoperitoneal shunts were placed 7-10 days prior to biopsy. The midbrain was biopsied 13 times, the pons 3 and the medulla 12 times. Tissue for histopathologic examination was obtained at each operation and demonstrated astrocytoma in 13 patients, glioblastoma in 6, 'no tumor seen' in 5 and ependymoma in 2. Astrocytomas were usually located in the upper brain stem, and all of the glioblastomas were located in the medulla. The operative mortality was zero, and the morbidity was largely related to increased cranial nerve deficit. All the astrocytoma patients were treated with radiation only; whereas, 4 patients with glioblastoma were treated with vincristine, CCNU and methylprednisone in addition to radiation as described by the Children's Cancer Study Group (CCG-944). 3 patients with 'no tumor' were not treated and are alive and well 15-41 months following operation. 2 patients with no tumor were treated, one as a glioblastoma multiforme, subsequently verified at postmortem examination, and one as a midbrain astrocytoma. 1 patient with astrocytoma died 3 months following operation, all the remainder are living and well 4-51 months following operation. Irrespective of the treatment, all 7 patients with glioblastoma expired within 9 months of diagnosis. The prognosis for survival for patients with brain stem astrocytoma is superior to those with glioblastoma multiforme. Specific histopathologic correlation with clinical management may lead to improved and prolonged survival for patients with brain stem glioma.