History of randomized clinical trials in neurosurgery.

The randomized clinical trial is a treatment evaluation technique that has been available in clinical research since 1946. Its first application in neurosurgery seems to have occurred in 1960 by McKissock and colleagues. Neurosurgery has been slow to adopt the technique, particularly in the evaluation of surgical therapy, but its use has increased in recent years.

Fate of rigid fixation in pediatric craniofacial surgery.

The advantages of rigid fixation in adult craniofacial surgery are well documented, and implanted hardware is not routinely removed unless specifically indicated. There is a tendency, however, to remove hardware in children because of concerns with growth restriction, plate migration, and the lack of information on the fate of miniplates when used in pediatric craniofacial surgery. It has been our practice during the past decade not to remove hardware in children unless specifically indicated. Our study included a total of 121 procedures in 96 children, with an average age of 3.9 years and an average follow-up of 5 years. We placed 375 titanium plates and 1944 screws from 3 manufacturers. Complications encountered in children with titanium plates were as follows: 5 cases of delayed growth and 1 instance of restricted growth, 4 screw migrations (none intracranial), 9 palpable plates causing pain, 3 fluid accumulations over plates, 2 cases of meningitis, and 8 instances of plate and screw removal from the above complications. Twenty-two of 96 patients (23%) had a total of 27 complications from 121 procedures (22%). There were 6 cases in which pain precipitated removal of hardware, 1 case of an excessively mobile plate, and 1 case of documented growth restriction requiring removal; therefore our overall reoperation rate for plate removal was 8%, with no intracranial plate or screw migration.

Fibrinolytic agents in the management of posthemorrhagic hydrocephalus in preterm infants: the evidence.

The objective of this study was to review current literature on the management of posthemorrhagic hydrocephalus in preterm infants with intraventricular administration of fibrinolytic agents; to this end a literature search was carried out electronically. The keywords used were "intraventricular hemorrhage" or "posthemorrhagic hydrocephalus" in combination with "fibrinolytic agent," "urokinase," "streptokinase," or "recombinant tissue plasminogen activator" and "intraventricular administration"; the search covered the years 1966-1998 and was restricted to English language papers and human subjects. It was supplemented by a search through the reference lists of the articles identified. Articles dealing with intracerebral hemorrhage or hematoma, intraventricular hemorrhage in adults, nontherapeutic issues and laboratory research were excluded. The articles included are summarized in evidence and evaluation tables. Five scientific publications evaluating the use of a fibrinolytic agent to manage posthemorrhagic hydrocephalus were retrieved. In the studies described in these reports, a total of 62 neonates received streptokinase, urokinase or r-tPA intraventricularly. No two of the regimens were identical in the drug used, method of administration and duration of therapy. The time before therapy was started ranged from 2 to 35 days after the ictus. Among the case series reported, three were small series with a total of 38 neonates. One other case series of 18 neonates compared the treatment group with an historical control group. All case series showed that endoventricular fibrinolytic therapy was practical. The proportion of cases in which shunt placement was performed ranged from 11% to 100%. Only one small prospective, randomized, controlled study was identified. That study was too small to allow useful conclusions. Overall, 3 cases of secondary intraventricular hemorrhage were reported. However, it was not possible to determine with certainty whether these episodes were related to the drug therapy itself. The reports suffer from inadequate study design, lack of descriptive information and short follow-up period. There is insufficient evidence to justify the claim that fibrinolytic agents administered intraventricularly in posthemorrhagic hydrocephalus are safe and effective. More evidence is needed to prove or disprove the effectiveness and safety of this form of therapy.

Cervical arachnoid cysts after craniocervical decompression for Chiari II malformations: report of three cases.

OBJECTIVE AND IMPORTANCE: We describe three cases in which ventrally situated cervical arachnoid cysts led to spinal cord or cervicomedullary compression after repeat craniocervical decompression for Chiari II malformations. CLINICAL PRESENTATION: All three patients underwent craniocervical decompression when their Chiari malformations became symptomatic. The first patient developed chronic vertiginous spells and headache and was treated with repeated craniocervical decompression procedures during several years. Seven months after undergoing her third decompression procedure, she developed severe dizzy spells, which were determined to be of brain stem origin. The second patient had a small, asymptomatic arachnoid cyst anterior to the brain stem discovered at age 6 years. After undergoing repeat craniocervical decompression for headaches 8 years after undergoing his first procedure, the patient developed severe neck pain and acute quadraparesis. A third patient underwent repeat craniocervical decompression at age 14 years for cranial nerve dysfunction. Postoperatively, he acutely developed paresis of extraocular movements and incoordination of the upper extremities. All three patients were found to have anteriorly situated arachnoid cysts compressing the brain stem and/or cervical spinal cord. INTERVENTION AND TECHNIQUE: Fenestration of the arachnoid cyst or drainage with cystoperitoneal shunting adequately treated acute brain stem or cervical spinal cord compression. All three patients had achieved satisfactory relief from their acute symptoms of neural compression at their follow-up examinations. CONCLUSION: An association between spinal arachnoid cysts and neural tube defects has previously been reported. However, the development of previously undetected spinal arachnoid cysts after craniocervical decompression was unexpected. We hypothesize that extensive craniocervical decompression may alter the cerebrospinal fluid pressure dynamics in such a way that the anterior subarachnoid space, previously compressed, may dilate. Occasionally, because of perimedullary arachnoiditis, the cerebrospinal fluid may become loculated and act as a mass. Direct fenestration or shunting may successfully treat this problem, and less extensive craniocervical decompression may avoid it.

Syringomyelia in mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome): imaging findings following bone marrow transplantation.

We present the imaging findings in a patient with mucopolysaccharidosis (MPS) type VI (Maroteaux-Lamy syndrome) who developed holocord syringomyelia. This represents the only reported case of syrinx formation in a child with MPS VI. Clinical, neurologic and spinal magnetic resonance imaging findings are presented. The patient has maintained a stable clinical and neurologic course over the period following allogeneic bone marrow transplant.

Outcome analysis of the transglabellar/subcranial approach for lesions of the anterior cranial fossa: a comparison with the classic craniotomy approach.

The classic approach to anterior skull base lesions uses bifrontal craniotomies together with lateral rhinotomies. This approach requires frontal lobe retraction and is associated with postoperative anosmia and the development of frontal lobe encephalomalacia. The transglabellar/subcranial approach permits removal of anterior skull base lesions without frontal lobe retraction and avoids facial scars. No studies to date, however, have directly compared the two approaches in terms of patient morbidity. The present retrospective study compares the two approaches when used for the removal of anterior skull base lesions in terms of estimated blood loss, number of transfusions, number of days in the hospital and intensive care unit, and postoperative complications. Twenty patients with anterior skull base lesions were examined. The classic approach was used on 10, and the transglabellar/subcranial route was used on 10. When compared with the classic approach, the transglabellar/subcranial approach resulted in a lower estimated blood loss and subsequent transfusion rate, fewer days in the hospital and intensive care unit, and lower numbers and less severe types of complications. Furthermore, visualization of the tumors before resection with the transglabellar/subcranial approach allowed preservation of olfaction in virtually all of these patients. Although this study represents a small sample population, the results are sufficiently impressive to favor the transglabellar/subcranial approach for the removal of a variety of anterior skull base lesions.

Repairing holes in the head: a history of cranioplasty.

Cranioplasty is almost as ancient as trephination, yet its fascinating history has been neglected. There is strong evidence that Incan surgeons were performing cranioplasty using precious metals and gourds. Interestingly, early surgical authors, such as Hippocrates and Galen, do not discuss cranioplasty and it was not until the 16th century that cranioplasty in the form of a gold plate was mentioned by Fallopius. The first bone graft was recorded by Meekeren, who in 1668 noted that canine bone was used to repair a cranial defect in a Russian man. The next advance in cranioplasty was the experimental groundwork in bone grafting, performed in the late 19th century. The use of autografts for cranioplasty became popular in the early 20th century. The destructive nature of 20th century warfare provided an impetus to search for alternative metals and plastics to cover large cranial defects. The metallic bone substitutes have largely been replaced by modern plastics. Methyl methacrylate was introduced in 1940 and is currently the most common material used. Research in cranioplasty is now directed at improving the ability of the host to regenerate bone. As modern day trephiners, neurosurgeons should be cognizant of how the technique of repairing a hole in the head has evolved.

Retrospective study of postcraniotomy headaches in suboccipital approach: diagnosis and management.

PURPOSE: The suboccipital approach used for cerebellopontine angle tumors, microvascular decompression, vestibular nerve section, and other procedures has been associated with significant postoperative headache. This study was undertaken to evaluate retrospectively the incidence and management of headaches in these patients. METHODS: Operation logs from 1988 through 1993 were reviewed to identify patients who underwent lateral suboccipital craniotomy or craniectomy. The nature of the operation, preoperative and postoperative complaints of headache, treatment for postoperative headache, and the use of primary cranioplasty were recorded from the medical records. RESULTS: Fifty-six suboccipital approaches were performed by the senior authors between 1988 and 1990. Seven patients had debilitating postoperative headaches. None responded to conservative management, and all underwent secondary cranioplasty. All seven patients showed significant improvement in their pain, with four of seven requiring no other treatment (follow-up from 15 to 38 months). Fifty patients underwent cranioplasty at the time of their initial operation, from 1991 to 1993. No case of debilitating headache was identified post-operatively in these patients. CONCLUSIONS: Cranioplasty at the time of lateral craniectomy appears to reduce the incidence of debilitating postoperative headache.

Knotted bowel: small-bowel obstruction from coiled peritoneal shunt catheters. Report of two cases.

Knotting of a peritoneal catheter around a loop of bowel is a rare occurrence, which may lead to bowel obstruction. The incomplete removal of two ventriculoperitoneal shunts resulted in two cases of iatrogenically knotted peritoneal catheters. One patient underwent a laparotomy for relief of obstruction and the other was successfully treated by uncoiling the catheter by means of a wire passed into its lumen. A plan for management of a knotted peritoneal catheter is outlined.

Review of skull base surgery approaches: with special reference to pediatric patients.

The techniques of skull base surgery attempt to maximize the exposure of a cranial base lesion while using the least amount of brain retraction. Cranial base surgery is not a 'new' area of neurosurgical or otolaryngologic interest, but instead represents a resurgence of efforts to treat difficult lesions involving the cranial base. This resurgence of interest and effort is a product of recent advances in microanatomical knowledge of the cranial base, advances in microsurgical technique, improved neurophysiologic monitoring, and improved collaborative relationships between neurosurgery, otolaryngology and plastic surgery. Furthermore, improved neuroanesthetic techniques allow the surgeon to proceed with surgery without undue concern about time, and improved neuroimaging techniques provide the surgeon with detailed knowledge of the three dimensional characteristics of the tumor and surrounding structures. This review will focus on the surgical management of cranial base tumors primarily affecting the pediatric population. Little has been written on the techniques of skull base surgery as they apply to the pediatric population, since cranially-based tumors are a relatively rare occurrence in this patient population. In most instances, however, many of the 'standard' skull base approaches can be applied to the pediatric patient with few modifications, and in our experience, the pediatric patients have tolerated these approaches as well as their adult counterparts.