Arnold H. Menezes

Pediatric spinal cord and vertebral column injury.

Between January 1, 1970, and December 31, 1988, 179 children (birth to age 16) were treated for spinal cord and/or vertebral column injury by the Neurosurgical Service at the University of Iowa Hospitals and Clinics. Pediatric injuries accounted for 9% of all spinal trauma seen during this period. The mean age was 10.2 years. Sixty-two children were between birth and 8 years of age and 117 were between ages 9 and 16. The cause, distribution, type of injury, and severity of neurological injury varied with age. Neurological outcome was dependent on the severity of the initial neurological injury. Children with complete or severe incomplete myelopathy uniformly remained with severe neurological dysfunction; children with mild to moderate injuries recovered normal or nearly normal neurological function. Surgical versus nonoperative management had no bearing on neurological outcome. Twelve percent of the children with severe spinal cord injuries developed posttraumatic spinal deformity. We conclude that spinal injury patterns differ between preadolescent and older children. Most injuries can be successfully managed with nonoperative therapy. Prognosis is primarily correlated with the severity of the initial neurological insult. Finally, children with severe spinal cord injury must have close, long-term follow-up to monitor the development of posttraumatic spinal deformity.

Diagnosis and management of pyogenic vertebral osteomyelitis in adults

Management of vertebral osteomyelitis remains controversial regarding optimum duration of antibiotic therapy and the role of surgery. Forty adults with vertebral osteomyelitis were reviewed. Staphylococcus aureus was the most common pathogen isolated. Disk space narrowing with end-plate erosion was the earliest finding, followed by progressive vertebral body destruction. Magnetic resonance imaging proved extremely valuable in detecting spinal cord compression in patients with neurologic deficit. Treatment should include at least 8 weeks of intravenous antibiotics combined with immobilization for pain reduction. Surgical intervention is indicated for all patients with neurologic deficit. Serial erythrocyte sedimentation rates are valuable for following response to therapy. The value of magnetic resonance imaging in diagnosis is emphasized.

Arthrodesis of the cervical spine in rheumatoid arthritis.

Forty-one patients who had rheumatoid arthritis were treated with a cervical arthrodesis and were followed for a minimum of twenty-three months. Twenty patients had had an isolated atlanto-axial subluxation; five, isolated cranial settling; and four, subaxial subluxation alone. Twenty patients had an atlanto-axial arthrodesis; sixteen, an occipitocervical arthrodesis; and five, a posterior arthrodesis of the subaxial spine. In addition, two patients had a transoral odontoidectomy and one, an anterior cervical vertebrectomy. At the latest follow-up, thirty-six (88 per cent) of the patients had osseous union, two had fibrous union but were stable, and three had a non-union. All of the problems with union occurred in the patients who had had an isolated atlanto-axial arthrodesis. Clinically, twenty-seven (66 per cent) of the patients had improved, fourteen were unchanged, and none were worse. The preoperative neurological status remained the same postoperatively in thirty patients (73 per cent) and it improved in eleven (27 per cent). Twenty-one of the twenty-three patients who had had marked pain preoperatively had little or no pain at the latest follow-up. Complications included a transient hemiparesis in one patient, a superficial wound infection in two, displacement of an anterior graft in one, a broken wire in three, and erosion of methylmethacrylate into the outer part of the occipital cortex in one. Four patients died, but not as a result of the operation.(ABSTRACT TRUNCATED AT 250 WORDS)

Idiopathic spinal epidural lipomatosis

OBJECTIVE Spinal epidural lipomatosis (SEDL) is a rare disorder often associated with the administration of exogenous steroids or the elevation of endogenous steroids. Spinal epidural lipomatosis develops in some patients in the absence of elevated steroid levels. The limited information known about idiopathic SEDL comes predominantly from isolated case reports. We proposed to study our experience with idiopathic SEDL and to review the literature. METHODS We identified eight symptomatic patients with idiopathic SEDL treated at our institution, which is the largest series reported. All patients were male and obese by body mass index (> 27.5 kg/m2). The mean age of the patients was 35.4 years. Idiopathic SEDL was equally distributed between the thoracic and lumbar spine. Six patients underwent laminectomy and fat debulking with good postoperative results; two patients were treated with a weight loss diet, which resulted in the relief of symptoms after losing > 15 kg each. RESULTS AND CONCLUSION A review of our patients in conjunction with other reported cases reveals the following: 1) idiopathic SEDL occurs almost exclusively in the obese population; 2) idiopathic SEDL seems to occur with equal frequency between the thoracic and lumber spine; 3) a strong male predominance exists; 4) thoracic SEDL presents at an earlier age compared with lumbar SEDL; 5) surgical decompression remains the treatment of choice for the immediate relief of symptoms. Our experience suggests that idiopathic epidural lipomatosis may be a pathological entity that has been underdiagnosed.

Primary Craniovertebral Anomalies and the Hindbrain Herniation Syndrome (Chiari I): Data Base Analysis

This prospective study analyzes 100 patients with Chiari malformation and primary craniovertebral junction (CVJ) anomalies (3-66 years). Neurodiagnostic investigations employed tomography, gas myelography, CT and CT myelography, and MRI. Factors considered were reducibility, mode of encroachment, cerebrospinal fluid (CSF) dynamics and syringohydromyelia. Sixty-six patients with irreducible pathology underwent ventral or ventrolateral decompression and dorsal stabilization. Dorsal occipitocervical fixation was performed in reducible lesions that also required dorsal decompression (n = 34). Proatlas remnants were identified in 8 and atlas assimilation in 92 patients. Paramesial invagination was present in 20, syringohydromyelia in 46, and vertebral segmentation defects in 66 others. Completely reducible abnormalities were identified in 16 of 20 patients aged 2-14 years, and partially reducible abnormalities in 4 of 16 patients aged 14-20 years, 8 of 48 patients aged 20-40 years and 6 of 16 patients aged 40-60 years. The critical sagittal canal diameter at the foramen magnum was 19 mm. Twenty-two patients had previous posterior decompression and 27 had previous syrinx to subarachnoid shunt with delayed deterioration. Improvement occurred in all after ventral or ventrolateral decompression with resolution of the syringohydromyelia and normalization of CSF flow. We conclude that: (1) hindbrain herniation syndrome is frequently seen with fourth occipital sclerotome abnormalities; (2) Chiari malformation with craniovertebral abnormalities become symptomatic with a canal diameter of < 19 mm; (3) abnormal ventral bony pathology is reducible in children wit atlas assimilation and later becomes irreducible invagination, therefore early operation with fusion is recommended; (4) ventral decompression relieves brain stem, cerebellar symptoms and syringohydromyelia; (5) CSF studies with cine MRI shows reversal of craniospinal CSF dissociation after ventral CVJ decompression and; (6) craniovertebral anomalies associated with Chiari malformations must be addressed early and appropriately.

Intracranial ependymomas: an analysis of prognostic factors and patterns of failure.

From 1965 to 1997, 49 patients were diagnosed and treated for intracranial ependymoma at one institution. Tumor location was infratentorial in two thirds, and pathology was low grade in 38 patients (78%). Gross total resection of the primary tumor was achieved in 21 (43%). Thirty-six patients received adjuvant radiotherapy; the entire neuraxis was treated in 14, whole brain in 10, and local field only in 12. Median follow-up was 9.6 years (range, 2–33 years). The 5-, 10-, and 15-year overall survival rates were 71.4%, 63.5%, and 63.5% for craniospinal radiotherapy, 60.0%, 60.0%, and 40.0% for whole brain radiotherapy, and 80.8%, 64.6%, and 64.6% for local field radiotherapy (p = 0.88). The 5-, 10-, and 15-year local control rates were 60.3%, 54.4%, and 48.9%. The prognostic factors for a better local control rate were gross total resection (p = 0.021) and low grade histology (p = 0.031). Seventeen of 43 (39.5%) M0 patients did not respond to treatment; all had local failure and 4 also had a spinal relapse. Spinal relapse developed in 3 of 31 (10%) M0 patients who did not receive spinal radiotherapy, whereas 1 of 12 (8%) who had spinal radiotherapy did not respond to treatment in the spine. The results of this study indicate that local radiotherapy is sufficient for M0 patients with intracranial ependymoma.

Pathogenesis and treatment of growing skull fractures

BACKGROUND Growing skull fractures are poorly understood complications of pediatric skull fractures. METHODS A retrospective review of skull fractures at our institution from 1980-1993 revealed 10 patients with growing skull fractures. The age at injury ranged from 1-144 months, with 9 of 10 patients being under one year of age. The etiology of these fractures included falls, motor vehicle accidents, and child abuse. On average, growth of the fracture was diagnosed 14 months after the initial injury. RESULTS Six patients have had magnetic resonance imaging (MRI) with one demonstrating leptomeningeal cyst herniation, two having brain herniation, and three having both brain parenchyma and leptomeningeal cyst herniation. All patients had malacic cortex underlying the fracture, but there was no evidence of intracranial hypertension. Nine patients have undergone craniotomy with excision of granulation tissue and gliotic brain, dural repair, and cranioplasty using surrounding normal skull. There were no surgical complications or recurrences. CONCLUSIONS Brain/leptomeningeal cyst herniation through a dural rent, without MRI evidence of increased intracranial pressure, implicates physiologic growth and brain cerebrospinal fluid (CSF) pulsations as the cause of fracture enlargement.

Diagnosis and management of the Dandy-Walker malformation: 30 years of experience.

Thirty-seven patients with Dandy-Walker malformation were treated between 1959 and 1989. Eighty percent of patients became symptomatic by 3 years of age, with 70% presenting within the 1st year of life. Hydrocephalus was present in 91% of patients at the time of diagnosis. Clinical presentation was most often heralded by symptoms and signs of hydrocephalus with focal neurological findings being a less prominent feature. One third of children demonstrated developmental delay. Associated congenital anomalies were present in 48% of children. Contemporary neuroimaging including computed tomography and magnetic resonance imaging facilitated diagnosis obviating the need for invasive studies such as pneumoencephalography and ventriculography. Patients were initially managed by posterior fossa craniectomy with membrane excision (8), lateral ventricle shunt alone (13), shunting of the cyst alone (4), or combined shunting of the cyst and lateral ventricles (12). Combined shunting proved superior to the other methods, being successful in alleviating hydrocephalus and posterior fossa symptoms in 92% cases. The overall mortality was 24%, the majority occurring before 1970. Of the 28 survivors, 27 (96%) are shunt-dependent, with 19 having a combined shunt system in place. Therefore, we currently favor combined shunting of the cyst and lateral ventricles as the initial procedure for patients with Dandy-Walker malformation.

Chiari I Malformations and Hydromyelia – Complications

The Chiari I malformation is associated with a hydromyelic cavity in 55-75% of patients. In the authors series (1977-1991), hydromelia occurred in 111 of 131 patients (85%). There were 35 children. Posterior fossa decompression with duraplasty and fourth ventricle to subarachnoid shunt was made in all patients with Chiari I malformation with hydromyelia. The obex connection to the cervical cord central canal was closed with muscle, if widely patent. Eighty-five percent showed sustained objective improvement. The precautions taken to avoid complications and a literature review are tabulated for easy reference.

Presentation and management of pediatric Chiari malformations without myelodysplasia.

Chiari malformations without myelodysplasia are rarely diagnosed in the pediatric age group. With current neurodiagnostic techniques, however, they are being seen more frequently. Unfortunately, the prognosis is not clear because publications have included a number of different entities, used a variety of surgical approaches, and lacked long term follow-up. Sixteen patients younger than 20 years were treated for Chiari malformations (without myelodysplasia) between 1975 and 1985. The average age was 11 years, and the average duration of symptoms was 20 months. The common symptoms were isolated motor weakness (56%), pain (37.5%), and sensory loss (25%). Frequently seen signs were motor deficit (81%), sensory loss (50%), scoliosis (50%), and cranial nerve palsy (50%). The surgical procedures used were foramen magnum decompression (3 transoral clivus odontoid resections and 15 posterior fossa decompressions with dural grafting), alteration of cerebrospinal fluid (CSF) pathways at the cervicomedullary junction (plugging the foramen cecum and a 4th ventricle to subarachnoid shunt with posterior fossa decompression), and ventriculoperitoneal shunting (2 cases). In follow-up, 37.5% of the patients are asymptomatic, 50% are improved, and 12.5% are stable after an average follow-up period of 43 months. The asymptomatic group was younger (9.3 years) and had a shorter symptom duration (7.2 months) than both the improved (11.9 years, 16.4 months) and the stable groups (15 years, 20 months). Optimal outcome depends on complete evaluation of the abnormal CSF pathways and bony abnormalities at the craniovertebral junction. Operation is then directed toward correction of these abnormalities as delineated radiographically. Of our patients, 87.5% have at least shown improvement, which has been long term in all cases.