Radiation exposure in the myelomeningocele population.

Radiation-induced carcinoma is known to occur with lower doses of radiation exposure than previously recognized. The myelomeningocele population, because of its complex medical problems, is exposed to relatively high doses of radiation from diagnostic radiographs performed throughout their lives. To quantify the amount of exposure, we have calculated the total lifetime radiographic exposure for patients in a myelomeningocele clinic. Out of a myelomeningocele clinic of 248 patients, 112 were identified who had been followed in the clinic since birth. A retrospective history of radiographic exposure was obtained for each patient by reviewing the hospital X-ray jackets. Using standard radiographic dose tables, calculations of total radiation exposure were performed for each patient. The total skin dose exposure ranged from 3.96 to 171.29 rad with a mean of 42.99 rad (SD 33.58). The total skin dose per year of life ranged from 0.79 to 37.81 rad/year of life with a mean of 6.38 rad/year of life (SD 5.72). The total red marrow dose ranged from 0.3 to 29.04 rad with a mean of 7.02 rad (SD 6.24). The total red marrow dose per year of life ranged from 0. 1 to 5.35 rad/year of life with a mean of 1.01 rad/year of life (SD 1.06). These data suggest that the radiation burden from diagnostic radiographs in the myelomeningocele population may ultimately contribute to carcinogenesis, mutagenesis and other radiation damage. Specific strategies for reducing the lifetime radiographic exposure in these patients are discussed in detail.

Laparoscopic surgery in a patient with a ventriculoperitoneal shunt: a new technique.

With advances in the treatment of hydrocephalus, patients with ventriculoperitoneal shunts (VPS) often have normal life expectancies. They are therefore more commonly requiring abdominal surgery. Laparoscopic surgery has become the favored technique for performing many of these operations. However, the presence of a VPS has been considered a contraindication or hazard in performing many of these laparoscopic operations. We present a case report of a laparoscopic Toupet fundoplication in a patient with a VPS and describe a technique for the successful management of the VPS throughout the procedure with no adverse sequelae.

Spontaneous bacterial peritonitis in patients with ventriculoperitoneal shunts.

Spontaneous bacterial peritonitis (SBP) is an infection of the peritoneal fluid in the absence of an obvious intra-abdominal source. It is most commonly diagnosed in patients with cirrhotic ascites, although it has been described in other syndromes as well. The organisms most frequently cultured from the peritoneum are those of intestinal flora; however, there are cases which have all the features of SBP, but remain culture negative. This article discusses 7 cases of SBP in patients with ventriculoperitoneal shunts; a combination which has previously not been described. The most significant features of these cases include: a remote history of shunt revision (mean 3.4 years), and cultures consistent with normal intestinal flora. None had a history of recent abdominal surgery, gastrostomy or wire-impregnated catheters. Cerebrospinal fluid cultures are often negative, and when positive, suggest SBP with an ascending shunt infection. While SBP is clearly differentiated from pseudocyst of the abdomen, it may represent a point on the continuum of intra-abdominal processes in the shunted patient. The precise etiology of SBP is unclear. A number of suggested theories are reviewed. It is proposed that patients with shunts may be predisposed to develop SBP because spinal fluid can behave as an ascitic fluid even in the absence of a peritoneal accumulation. Recommendations for the recognition and management of SBP in the shunted patient are discussed in detail.

The Currarino triad: its importance in pediatric neurosurgery.

Currarino's triad is a hereditary condition diagnosed when three abnormalities are noted: (1) an anorectal malformation; (2) an anterior sacral defect, and (3) a presacral mass. This condition often presents with symptoms related to the presacral mass or with an incidental finding of a sacral anomaly on plain radiographs. Presented here are 2 cases of Currarino's triad noted in siblings, both of whom underwent surgery for anorectal malformations in infancy. The importance of early diagnosis and treatment of this condition and the need for genetic counseling are emphasized.

A prospective evaluation of leak point pressure, bladder compliance and clinical status in myelodysplasia patients with tethered spinal cords.

We evaluated prospectively 26 patients with myelodysplasia and a tethered spinal cord to determine whether surgical release of the tethered cord positively influenced leak point pressure, bladder compliance, upper tract status and/or clinical management. Urodynamics were performed immediately before and after the neurosurgical procedure, and at 3 and 6 months postoperatively. Mean patient age was 7.8 years (range 2 days to 34 years) and median interval from onset of symptoms to surgery was 60 days (range 2 days to 4 years). Patient presentation included a combination of orthopedic, neurological and urological symptoms. Of 26 patients 9 (35%) had new hydronephrosis, urinary tract infections or urinary incontinence. Leak point pressure and bladder compliance did not change significantly by 6 months postoperatively. Of the 4 patients who presented with hydronephrosis 1 worsened in status, 2 stabilized and 1 improved. Clinical status was unchanged in 16 patients, improved in 4 and worsened in 6. There was no significant relationship between patient age and urodynamic or clinical outcome. Among patients followed for at least 6 months radiographic and clinical improvement occurred in 25% and 15%, respectively. Urodynamic improvements were transient. Surgical release of a tethered cord improved the urological status in less than a quarter of the patients in this series.

Improvement in upper extremity function and trunk control after selective posterior rhizotomy.

Selective posterior rhizotomy is being increasingly used in the treatment of spasticity associated with cerebral palsy. Anecdotal reports in the literature note that this procedure results in improved upper extremity function and trunk control. We present a systematic analysis of the results of selective posterior rhizotomy performed on patients with cerebral palsy at Santa Rosa Children's Hospital. Patients were video-taped before surgery and one year postoperatively. These videos were reviewed blind by an occupational therapist who graded patients' performance on three tasks: assumption of side sitting, maintenance of side sitting, and block building. Statistically significant improvements were noted in all three categories with p values of .0003, .0001, and .0044 respectively. These results support the anecdotal reports of improvement in upper extremity function and trunk control with selective posterior rhizotomy.

Giant bilateral xanthogranulomas in a child: case report.

Symptomatic xanthogranulomas are rare lesions that most commonly occur in adults. A case of giant bilateral xanthogranulomas in a 6-year-old boy, who remains without tumor recurrence 9 years after resection, is presented. The operative management of these unusually large lesions is discussed. The pathogenesis of xanthogranulomas is reviewed as it relates to the presentation of these lesions in the pediatric population.

Selective posterior rhizotomy to treat spasticity associated with cerebral palsy: a critical review.

Selective posterior rhizotomy for the treatment of spasticity has become a widely used procedure. The historical evolution of this procedure is reviewed with an emphasis on the physiological basis for the procedure. The proper screening and selection criteria, perioperative management, operative technique, and postoperative therapy are discussed. Results from a series of 25 patients are reviewed. Ten of these patients were operated on for a goal of improved ease in caretaking and this was achieved. In seven patients, the goal was to improve independent functioning (ambulation was not considered possible) and this was achieved. Eight patients underwent the procedure to improve ambulation and this was achieved.

Vancomycin: its effect on intracranial pressure.

Vancomycin is a commonly used antibiotic in neurosurgical practice. It is, however, notorious for causing histamine release which has been associated experimentally with rises in intracranial pressure (ICP). The observation that patients receiving vancomycin had an elevation in ICP during vancomycin infusion over 1 h, and that this elevation persisted for the hour following infusion led to a more formal evaluation. Presented here are data obtained from 6 patients who received vancomycin while on external ventricular drainage for a variety of reasons. The mean ICP for the hour prior to, during and following vancomycin administration was 8 mm Hg (SD 5.6), 13.8 mm Hg (SD 4.9), and 12.6 mm Hg (SD 4.3), respectively. The data were analyzed using a repeated measures analysis of variance between the preadministration values, during-administration values and postadministration values. The p value was significant at < 0.0001. These observations led to experimentation in animals to further assess the effects of vancomycin on ICP. The mean ICP prior to, during and following vancomycin infusion was 1.95 mm Hg (SD 0.75), 8.4 mm Hg (SD 5.1) and 5.6 mm Hg (SD 2.5), respectively. The data were analyzed using a repeated measure analysis of variance for the preadministration, during-administration and postadministration values. The p value was significant at < 0.0001. Based on these data the use of vancomycin should be tempered in the setting of intracranial pathology.

Transient eye closure after posterior fossa tumor surgery in children.

Transient cerebellar eye closure following posterior fossa tumor surgery in children has recently been observed. This phenomenon is characterized by a transient inability to open the eyes postoperatively with complete resolution within 4-6 days. Presented are four cases of transient cerebellar eye closure after posterior fossa tumor surgery in children. Possible mechanisms are reviewed with regard to historical works of cerebellar stimulation in man, and anatomical structures and pathways which might be involved.

Continuous external drainage in the treatment of subdural hematomas of infancy.

A series of 16 patients with chronic or subacute subdural hematomas treated with continuous external drainage of the subdural space is reviewed. Of these only 44% went on to require subdural-peritoneal shunt placement. There were no complications in treatment and no clinical or laboratory evidence of infection in any case. The outcome, measured by neurological examination, was not different between the shunted and nonshunted groups. In conclusion, continuous external drainage of the subdural space in chronic and subacute hematomas of infancy frequently is an effective, definitive treatment. This approach should be considered as the initial procedure prior to subdural-peritoneal shunting.

Custom fitted thermoplastic Minerva jackets in the treatment of cervical spine instability in preschool age children.

The options for cervical spine stabilization have traditionally been the Minerva jacket (MJ) or the halo brace. In the preschool age child both of these devices have significant drawbacks; the halo brace because of its erosion and difficulty providing adequate fixation due to the thin calvarium of the young child and the MJ because of its bulk and weight. With the advent of polyethylene plastics, MJs are a more viable option without the disadvantages noted above. Six cases of cervical spine instability in preschool age children treated with a custom-molded MJ are presented. All patients achieved cervical spine stability with minimal morbidity. This technique is recommended as an alternative to the halo brace, as it provides reliable and satisfactory treatment of these difficult problems in preschool children.

Postoperative chemotherapy for primary intracranial germ cell tumor.

Two children with primary intracranial mixed germ cell tumors are described who were successfully treated by partial resection of the tumor followed by sequential combination chemotherapy without radiation therapy. The chemotherapy consisting of VP-16 and cisplatin alternating with vincristine, methotrexate, and bleomycin resulted in apparent complete response after 6 to 7 months of treatment. Disease-free remission has continued 30-34 months off therapy. A small residual mass in one patient continues to decrease in size on magnetic resonance imaging and is presumed to represent postsurgical change rather than malignant tumor. This report demonstrates that chemotherapy may be effective in primary germ cell tumors of the suprasellar and pineal regions and could be considered for primary treatment instead of radiotherapy.

Neuroectodermal appendages: the human tail explained.

The human tail has been intermittently described in the literature since the early 1900s. These have typically been isolated cases presented primarily with intrigue and medical curiosity. Presented here is a series of 6 neuroectodermal appendages with a proposal for their etiological development. The material presented will support a theory of the superficial extension of a dermal sinus tract in the formation of neuroectodermal appendages. These are characterized by: a posterior localization in or near the midline, a tubular or 'tail-like' appearance, extension of the appendage into the spinal canal with attachment to neural elements, variable vertebral defects and occasionally an associated appendage which may appear as either a separate entity (probably due to breakage during development) or in connection with the posterior appendage. The appropriate evaluation and treatment of this entity will also be discussed.

Pseudocysts of the abdomen associated with ventriculoperitoneal shunts: a report of twelve cases and a review of the literature.

Shunt complications are reported to occur at a rate of approximately 26%. One of the less frequent but important complications is that of the pseudocyst. Since Harsh's first mention of a periumbilical cyst associated with a shunt in 1954, 44 cases have been reported in the literature. These are reviewed in addition to 12 cases of our own. From the collected series several features about the etiology and management become apparent. The most common presentation is that of abdominal distension and/or pain rather than shunt malfunction. Diagnosis is then readily made with ultrasonography. Etiologically, it is evident that an inflammatory process is a frequent predisposing factor. In our series 16% had acute infection, 41.6% had a past history of CSF infection (6 months to 6.2 years), and 16% had CNS tumor although tumor cells were not isolated from the peritoneal cysts. Our management of the cyst itself was different from that reported in other series; it was found that the cyst reabsorbed spontaneously without excision or aspiration once the CSF was diverted. The peritoneal cavity could then be used for shunting once the cyst had reabsorbed. This sometimes required conversion to an atrial or pleural shunt before reutilization of the peritoneal cavity. There were no problems with cyst recurrence despite the conversion of 58% of the shunts to ventriculoperitoneal shunts with follow-up ranging from 3 months to 4 years. The mode of management of both the cyst and the hydrocephalus is reviewed.

The subcutaneous ventricular reservoir: an effective treatment for posthemorrhagic hydrocephalus.

Use of the subcutaneous ventricular reservoir in the treatment of posthemorrhagic hydrocephalus was studied in a series of 38 patients. All of the patients were considered to be medically labile. Additionally, all had failed conservative modes of therapy consisting of lumbar punctures with or without furosemide or acetazolamide. Management of the hydrocephalus consisted of reservoir placement. Subsequently, taps were performed at various intervals and amounts, depending upon the degree of ventricular dilatation as determined by sonography and signs of increased intracranial pressure. The majority of reservoirs were left in place for 1-2 months. There were no reservoir infections. Once the patients were medically stable, the reservoir was removed and a shunt placed. Eight patients died before shunt placement and 2 patients died after shunting, reflecting a 29% mortality. In no case was a death related to the shunt, but rather reflected the medical lability of the patient population. Four patients (15% of surviving patients) did not require shunting. The total shunt infection rate was 6.9% (among survivors with a shunt in place, 7.7%). These results support the use of the reservoir as an easy and effective means of protecting the cortical mantle while decreasing morbidity related to future shunt placement.

Assessment of quality of survival in children with medulloblastoma and cerebellar astrocytoma.

To determine the quality of survival for children with posterior fossa tumors, comprehensive neuropsychological, behavioral, and academic assessment and physician ratings of functional status were obtained on 15 brain tumor patients (ages 6-19 years) at a median of 20 months post-diagnosis. More than 50% of the children (whether irradiated or not) experienced major problems in academic, motor, sensory, cognitive, and emotional function. All but two children were reported by teachers to be "slow workers," and four of 15 patients were able to maintain their school work in regular classes. Although 80% of the patients were rated by physicians as having "excellent" or "good" functional status, no relationship was found between these global ratings and psychometric measures. Although the affected site was the posterior fossa, deficits also involved higher cortical function. These findings indicate the need for further evaluation of treatment effects and the provision of intervention for survivors.