Posterior fossa decompression for children with Chiari I malformation and hydrocephalus.

INTRODUCTION: Chiari I malformation (CMI) and hydrocephalus often coexist, with no clear understanding of the cause-and-effect relationship. In the absence of other associated etiologies, the traditional teaching has been to treat the hydrocephalus first, partly to minimize the risk of cerebrospinal fluid (CSF) leak from CMI decompression in the setting of elevated ICP. We describe a series of consecutive pediatric patients with CMI and hydrocephalus, the majority of whom were managed with posterior fossa decompression. METHODS: A retrospective review was conducted on consecutive children who presented to the senior author with both hydrocephalus and CMI, with emphasis on rationale for and outcomes of surgical intervention, including the need for additional surgery. RESULTS: There were 14 patients aged 2 weeks to 16 years (median 2 years) who presented with Chiari I and hydrocephalus. Four of these underwent posterior fossa decompression without duraplasty (PFD) as first-line therapy (one of whom eventually required duraplasty), 7 had PFD with duraplasty (PFDD), 1 received a ventriculoperitoneal shunt (VPS), and two had endoscopic third ventriculostomy (ETV). Of the 11 who had PFD/D, 9 (90%) had significant symptom improvement/resolution, 7 (55%) showed decrease in ventricle size, and 1 (10%) required VPS placement for persistent hydrocephalus. Both ETV patients improved clinically, and 1 showed decrease in ventricle size. There were no pseudomeningoceles, infections, or neurological deficits. One CSF leak occurred after an ETV and was successfully treated with wound revision. CONCLUSION: In patients with both CMI and hydrocephalus, treating the CMI first in an effort to avoid a shunt can be safe and effective. In this series, PFDD in the setting of hydrocephalus did not result in CSF leak or pseudomeningocele. While limited by a small sample size, these data support a causative relationship between CMI and hydrocephalus.

Cytokine profile of patients with leptospirosis in Sabah, Malaysia.

BACKGROUND: Leptospirosis is a zoonotic disease with symptoms ranging from a mild, febrile illness to a severe form with multiorgan failure. Severe leptospirosis may require medical interventions in the form of dialysis and/or mechanical ventilation and often leads to mortality. An exaggerated host immune response-in particular, a "cytokine storm"-that causes endothelial and organ damage is associated with the disease severity and mortality. METHODS: Microscopic agglutination test (MAT)-positive and MAT-negative human serum samples (n=30) from patients with leptospirosis were obtained from the Public Health Laboratory, Kota Kinabalu, Sabah, Malaysia and control serum samples (n=10) were obtained from healthy student volunteers. We estimated the levels of IL-1ß, IL-6, IL-8, IL-10, and TNF-α in serum samples by a Luminex assay. RESULTS: The levels of IL-6, IL-8, and IL1-ß were significantly higher in 13% of the patients with leptospirosis compared to the healthy controls, while the levels of IL-10 and TNF-α were not elevated in either group. CONCLUSION: Our data suggest that elevated levels of IL-6, IL- 8, and IL1-ß may be associated with leptospirosis disease severity, which requires patient follow-up for confirmation.

Diagnosis and surgical treatment of an intracranial cyst in an alpaca cria.

CASE DESCRIPTION: A 7-day-old female alpaca was examined because of an acute onset of diffuse central neurologic deficits. CLINICAL FINDINGS: Diagnostic imaging with CT and MRI identified an intracranial cyst occupying approximately one-third to one-half of the dorsal portion of the cranial cavity, markedly displacing the cerebral hemispheres bilaterally. TREATMENT AND OUTCOME: Initial surgical management via trephination and needle drainage was only transiently effective at resolving the neurologic signs. Craniotomy and drainage and removal of the cyst lining resulted in a sustained improvement in neurologic status, and the cria remained clinically normal and well grown at follow-up 5 months after surgery. CLINICAL RELEVANCE: This report represented the first description of the successful treatment of an intracranial cyst in a New World camelid.

Recording CSF pressure with a transducer-tipped wire in an animal model of Chiari I.

In dogs, a wire with a pressure-sensitive transducer was inserted percutaneously into the subarachnoid space and manipulated under fluoroscopic monitoring in the posterior fossa or upper cervical spinal canal. Pressure recordings from the wire showed fluctuations in pressure corresponding to the cardiac cycle. When a balloon was distended in the foramen magnum, maximum and minimum pressures increased. Continuous monitoring of CSF pressure remote from the site of cannulation was feasible with a wire-based pressure transducer.

Measuring CSF Flow in Chiari I Malformations.

Cardiac-gated Phase Contrast MR (PC MR) is used in the evaluation of the Chiari I malformation to assess the CSF flow though the foramen magnum. Images may show reduced CSF flow posterior to the spinal cord in patients with a Chiari I malformation. MR images however do not differentiate with sufficient accuracy between symptomatic and asymptomatic Chiari I malformations. In the presence of the Chiari I malformation, CSF velocities are elevated. Measuring the velocity of flow and determining the degree of inhomogeneity in CSF flow aid in the detection of clinically significant flow abnormalities.

Spinal axon regeneration evoked by replacing two growth cone proteins in adult neurons.

In contrast to peripheral nerves, damaged axons in the mammalian brain and spinal cord rarely regenerate. Peripheral nerve injury stimulates neuronal expression of many genes that are not generally induced by CNS lesions, but it is not known which of these genes are required for regeneration. Here we show that co-expressing two major growth cone proteins, GAP-43 and CAP-23, can elicit long axon extension by adult dorsal root ganglion (DRG) neurons in vitro. Moreover, this expression triggers a 60-fold increase in regeneration of DRG axons in adult mice after spinal cord injury in vivo. Replacing key growth cone components, therefore, could be an effective way to stimulate regeneration of CNS axons.

Congenital tethered spinal cord syndrome in adults.

OBJECT: The management of tethered cord syndrome with onset of symptomatology occurring in adulthood remains controversial, although the necessity of early surgery in the pediatric tethered cord syndrome population is well established. To ascertain the results of surgery in adult patients with this anomaly, the authors undertook a retrospective review of 34 cases. METHODS: The authors studied the hospital records of 34 consecutive patients who presented in adulthood with tethered cord syndrome and conducted follow-up phone interviews with 28 of them. The population consisted of 12 men and 22 women, ranging in age from 18 to 70 years (mean 34 years). The most common presenting feature was pain, followed by weakness and incontinence. All patients underwent surgery. The most common operative findings were tight filum terminale, split cord malformation, and lipomyelomeningocele, paralleling those observed in pediatric studies. Long-term surgical results and patient outcome ratings were encouraging. After a mean clinical follow-up period of 4 years, significant improvement occurred in 22 of 27 patients presenting with pain, 13 of 27 patients with motor or sensory dysfunction, and 11 of 18 patients with bowel and bladder disturbance. In addition, telephone interviews were obtained after a period of 8.6 years. Twenty-two (79%) of 28 patients called the operation a long-term success; 21 (75%) of 28 patients believed that they had significant postoperative improvement (and not just stabilization) in pain and/or neurological function. Surgical complications were generally minor. Surgery-related complications included one cerebrospinal fluid leak and five pseudomeningoceles. Two patients complained of worsening motor or sensory dysfunction and one of worsening bladder dysfunction, whereas four patients experienced persistent pain and one complained of worsening pain postoperatively. According to the patients, the vast majority of these complications were minor. Nineteen (86%) of 22 employed patients returned to work after surgery. Two (33%) of six patients who were not employed before surgery worked full time postoperatively. Only two of the 28 patients interviewed had received Workers' Compensation benefits; both of these had good outcomes and returned to work. CONCLUSIONS: Tethered spinal cord syndrome in adults is an uncommon entity that can become symptomatic. Although surgery in adults involves greater risk of neurological injury than in children, it is a low-risk procedure with encouraging results. Because neurological deficits are generally irreversible, early surgery is recommended.

A pictoral guide to pediatric epilepsy surgery.

This article contains a discussion and detailed pictorial account of diagnostic and neurosurgical therapeutic procedures used to help pediatric patients who have medically intractable epilepsy. The operations discussed are placement of sphenoidal electrodes, strips and grids, temporal and extratemporal resections, corpus callosotomy, and hemispherectomy.

Modern neurosurgery for psychiatric disorders.

OBJECTIVE: The evolution, rationale, and results of modern functional neurosurgery to treat psychiatric disorders are documented. The potential benefits of neurosurgical treatment for selected, critically ill, psychiatric patients are considered. METHODS: The history, anatomic features, and evolution of and contemporary indications for the four currently used procedures (cingulotomy, subcaudate tractotomy, limbic leukotomy, and capsulotomy) are reviewed. Available outcome, neuropsychological assessment, and functional imaging data are presented. RESULTS: Recently, there has been a renaissance of interest in the surgical treatment of psychiatric disease. Modern psychiatric neurosurgical procedures are quite safe, with extremely low surgical mortality rates and transient postoperative morbidity. In selected cases, patients with conditions that had previously been completely refractory to comprehensive medical and behavioral intervention demonstrated significant improvement. This improvement was usually observed in the absence of long-term adverse neuropsychological consequences. CONCLUSION: Recent outcome studies, together with advances in neurobiology, psychiatry, functional imaging, and stereotaxy, support the further investigation of modern functional neurosurgical procedures to treat psychiatric disorders and their application for a subset of psychiatric patients with conditions refractory to all other therapies.

Split cord malformations in myelomeningocele patients.

Split cord malformations (SCMs) may occur in conjunction with myelomeningoceles, and are often ignored or misdiagnosed, potentially causing spinal cord tethering. In this paper, we study the incidence and clinical significance of such an association. We have retrospectively reviewed the medical records and radiographs of 20 myelomeningocele patients who had a SCM. These comprised at least 6% of our myelomeningocele patients. Five of the 20 had simultaneous repair of both lesions at birth. The other 15 were diagnosed with the SCM in a delayed fashion (mean age 4.4 years). Clinical presentations that prompted a diagnostic investigation included hypertrichosis (1), pain (2), routine radiographic follow-up (2), neurourological deterioration (10) and progressive scoliosis (5). In 17 of the 20 patients, the SCM involved the placode or was within one level of it. Fifteen of these were in the area of the placode or one segment above it. Five of the 20 patients had hypertrichosis and 15 of the 20 patients had a bony midline septum (i.e. type I SCM). Several accompanying spinal dysraphic lesions also contributed to the tethering: thickened (previously inconspicuous) filum terminale (6), syringohydromyelia (5) and a neurenteric cyst with a benign teratoma (1). Arachnoiditis secondary to the prior myelomeningocele repair was found, as expected, in all 15 patients. However, in virtually all patients, there was also evidence of tethering at the level of the SCM. Long-term follow-up showed stabilization of preoperative symptoms and signs, whereas complications of the operation and clinical evidence of retethering were uncommon. Myelomeningocele patients should be screened with clinical examinations looking for hypertrichosis and with spinal radiographs preoperatively looking for evidence of SCM (bony midline septum and/or interpedicular widening not due to the myelomeningocele). Intraoperatively, the placode and the rostral spinal cord segment should be carefully inspected for an SCM and other dysraphic lesions.

Death in shunted hydrocephalic children in the 1990s.

Using a combined search of the Children's Hospital (Birmingham, Ala., USA) medical records and the Jefferson County Health Department death records, we reviewed all shunt-related deaths that occurred between January 1990 and July 1996. Of these, we excluded patients who died of nonhydrocephalus-related reasons, such as bronchopulmonary dysplasia, as well as patients who had other serious neurological illnesses such as brain tumor and hydranencephaly. Twenty-eight patients died of shunt-related causes in the 6.5-year period. A survival analysis showed that 96% survived 32 months after first shunting. Of 28 patients, 23 were beyond help prior to medical evaluation. However, at least 10 of these patients had symptoms suggestive of shunt failure at least 24 h and as long as 2 weeks prior to their demise. We conclude that hydrocephalic children still die of shunt failure despite the modern technology of the 1990s. Some of these causes may be avoidable through early detection of symptoms. Guidelines to patients, families, and primary caregivers should be emphasized.

The resolution of syringohydromyelia without hindbrain herniation after posterior fossa decompression.

OBJECT: To provide more information about this rare condition, the authors describe five cases of syringohydromyelia without hindbrain herniation. Preoperative magnetic resonance imaging with and without gadolinium-diethylenetriamine pentaacetic acid revealed no evidence of spinal cord tumor, arachnoiditis, or spinal dysraphism. METHODS: Craniocervical decompression was performed in all patients, after which there was resolution of the symptoms in the four symptomatic patients, and all five showed marked reduction in the size of the syrinx. CONCLUSIONS: The authors hypothesize the rare occurrence of syringohydromyelia resulting from a Chiari-like pathophysiological condition but lacking a hindbrain hernia. Patients with this condition may benefit from craniocervical decompression.

Pitfalls in the diagnosis of ventricular shunt dysfunction: radiology reports and ventricular size.

INTRODUCTION: The diagnosis of shunt malfunction can be difficult even for the experienced clinician and may lead to disastrous circumstances when misinterpreted. Less experienced physicians may rely more on radiographic reports as a primary diagnostic modality. In this study, we evaluated the reliability of using these reports without accurate clinical assessment. METHODS: All shunt revisions seen at Children's Hospital (Birmingham, AL) between January 1996 and August 1996 were reviewed, excluding patients with brain tumors, supratentorial extraaxial fluid collections, and infections. Sixty-eight patients underwent 100 operations for shunt malfunction. All patients had evidence of shunt blockage, disconnection, catheter malposition, or valve pressure incompatibility. The prospective radiographic interpretation of preoperative computed tomography and magnetic resonance imaging scans was reviewed in each case. RESULTS: Twenty-four percent of the reports made no mention of shunt malfunction. In this group, the ventricular system was described as "unchanged," "stable," "normal," "unremarkable," "small," "smaller," "slit," "negative," and "no hydrocephalus," with no other comment to support a diagnosis of shunt malfunction. An additional 9% of reports contained the same terms, while also hinting at some other clinical or radiographic data that suggest the possibility of shunt failure (e.g., a shunt disconnection seen on plain radiographs), despite the scan findings. In all patients in this group, symptoms improved after surgery. CONCLUSION: We conclude that as many as one third of patients presenting with shunt malfunction will not have the diagnosis of shunt malfunction supported by a prospective radiologic interpretation of brain imaging. Although the neurosurgical community can assess the clinical situation to determine the need for surgery, other clinicians can be easily reassured by a radiographic report that does not mention or diagnose shunt malfunction. Today, more than ever, nonneurosurgeons are being called on to evaluate complex clinical situations and may rely on radiographic reports.

Congenital tethered spinal cord syndrome in adults.

OBJECT: The management of tethered spinal cord syndrome with onset of symptomatology occurring in adulthood remains controversial, although the necessity of early surgery in the pediatric tethered cord syndrome population is well established. To ascertain the results of surgery in adult patients with this anomaly, the authors undertook a retrospective review of 34 cases. METHODS: The authors studied the hospital records of 34 consecutive patients who presented in adulthood with tethered cord syndrome and conducted follow-up phone interviews with 28 of them. The population consisted of 12 men and 22 women, ranging in age from 18 to 70 years (mean 34 years). The most common presenting feature was pain, followed by weakness and incontinence. All patients underwent surgery. The most common operative findings were tight filum terminale, split cord malformation, and lipomyelomeningocele, paralleling those observed in pediatric studies. Long-term surgical results and patient outcome ratings were encouraging. After a mean clinical follow-up period of 4 years, significant improvement occurred in 22 of 27 patients presenting with pain, 13 of 27 patients with motor or sensory dysfunction, and 11 of 18 patients with bowel and bladder disturbance. In addition, telephone interviews were obtained after a period of 8.6 years. Twenty-two (79%) of 28 patients called the operation a long-term success; 21 (75%) of 28 patients believed that they had significant postoperative improvement (and not just stabilization) in pain and/or neurological function. Surgical complications were generally minor. Nineteen (86%) of 22 employed patients returned to work after surgery. Two (33%) of six patients who were not employed before surgery worked full time postoperatively. Only two of the 28 patients interviewed had received Workers' Compensation benefits; both of these had good outcomes and returned to work. CONCLUSIONS: Tethered spinal cord syndrome in adults is an uncommon entity that can become symptomatic. Although surgery in adults involves greater risk of neurological injury than in children, it is a low-risk procedure with encouraging results. Because neurological deficits are generally irreversible, early surgery is recommended.

History of functional neurosurgery.

Whereas in the early days of evil spirits, electric catfish, and phrenology, functional neurosurgery was based on crude observations and dogma, the progress made in neurophysiology at the turn of the century gave the field a strong scientific foundation. Subsequently, the advent of stereotaxis allowed access to deep brain regions and contributed an element of precision. Future directions include the development of frameless stereotaxy; the use of MRI-generated anatomic data, which would circumvent the serious problem of individual variations seen with standard brain atlases; the introduction of various chemicals into brain structures, in an attempt to influence neurochemically mediated disease processes; and finally, the use of the promising techniques of neural transplantation. On hearing of Penfield's intraoperative brain stimulations, Sherrington commented: "It must be great fun to have the physiological preparation speak to you." The idea of therapeutic neurophysiologic interventions is appealing, especially because many disorders show no obvious treatable pathologic cause (e.g., tumor, vascular malformation). As stereotactic technology becomes less cumbersome and more precise, more sophisticated in vivo neurophysiologic preparations become possible. In turn, as our understanding of nervous system physiology grows, our ability to understand pathophysiology and treat disease processes increases.

Terminal syringohydromyelia and occult spinal dysraphism.

Terminal syringohydromyelia is a cystic dilatation of the lower third of the spinal cord. The authors describe its incidence and characteristics, its frequent association with occult spinal dysraphism, and its clinical significance and need for surgical treatment. All 143 cases of occult spinal dysraphism treated at the Duke University Medical Center between 1972 and 1992 were reviewed. A terminal syrinx was found in 24 (27%) of the 90 cases that were evaluated by magnetic resonance (MR) imaging. In contrast three (6.2%) of 48 cases evaluated by myelography and postmyelographic computerized tomography had a syrinx documented. The relative radiographic severity of the different syringes was estimated by using measurements of the syrinx and spinal cord on the MR images, classifying the cysts into large and small. Large syringes were frequently symptomatic, commonly presenting with pain, motor and sensory deficits of the lower extremities, scoliosis, and bowel and bladder dysfunction. Terminal syringohydromyelia with occult spinal dysraphic lesions was most often associated with tethered spinal cord from a tight filum terminale in the presence of an anorectal anomaly (67% of cases), meningocele manqué (54%), and diastematomyelia (38%). An infrequent association was seen with other spinal cord anomalies. The results of surgical management of terminal syringohydromyelia were analyzed, highlighting the necessity and effectiveness of shunting the large cysts, especially in the setting of a progressive symptomatology. Of the 11 patients with shunts who underwent MR imaging, 10 showed either complete or significant resolution of the syrinx; all five patients who had presented with pain (mainly back pain) showed complete resolution of the pain after shunting; finally, one-third of patients with shunt placement had significant postoperative improvement in their neurological examination, whereas none worsened. It is stressed that terminal syringohydromyelia is an important pathological entity that should be considered in patients with occult spinal dysraphism, and treated surgically when clinically or radiographically significant.