David I. Sandberg
Acute neurological deficit after minor trauma in an infant with achondroplasia and cervicomedullary compression
Case report and review of the literature
David M. Benglis and David I. Sandberg
✓Cervicomedullary compression at the foramen magnum in patients with achondroplasia can be associated with apnea, neurological deficits, and sudden death. Decompressive operations are often performed in symptomatic patients. In asymptomatic patients, the indications for prophylactic decompression are controversial. The authors present the case of a previously neurologically intact 4-month-old girl with achondroplasia who presented with severe hemiparesis after a low-velocity motor vehicle accident. Imaging studies demonstrated osseous compression of the medulla and upper cervical spinal cord with associated parenchymal signal changes. To the authors' knowledge this is the first reported case of a new neurological deficit after a minor trauma in this patient population. The authors review the relevant literature, focusing on the indications for cervicomedullary decompression in infants with achondroplasia. They propose that asymptomatic patients with achondroplasia and osseous compression at the foramen magnum should be offered prophy-lactic surgery if T2-weighted magnetic resonance imaging signal changes in the spinal cord are observed. Prophylactic surgery can be considered an option in patients whose imaging studies do not show signal changes in the spinal cord but demonstrate significant osseous compression and absence of visible subarachnoid spaces.
Anitha Nimmagadda, David I. Sandberg and John Ragheb
✓ The authors report the case of a newborn presenting at birth with macrocephaly and a large pineal region hemorrhagic cyst without neurological deficit. No neurosurgical intervention was performed, and subsequent imaging studies demonstrated complete involution of the cyst.
Yoshua Esquenazi, David I. Sandberg and Harold L. Rekate
Hypothalamic hamartomas (HHs) are benign lesions that are often associated with central precocious puberty and may present with gelastic seizures. Treatment modalities for HH include medical therapy with long-term gonadotropin-releasing hormone analogs or resection. The authors report the case of a 7-year-old girl who was diagnosed with an HH due to precocious puberty and was treated medically with a gonadotropin-releasing hormone analog for 3 years. Despite normalization of her plasma levels of luteinizing hormone, follicle-stimulating hormone, and estradiol and arrest of her precocious puberty, the patient developed progressive weight gain associated with extreme hyperphagia and morbid obesity by the age of 10 years. Her compulsive eating patterns were refractory to counseling and other interventions attempted by her parents and physicians. After resection of the HH, her hyperphagia resolved and her weight stabilized. To the authors' knowledge, this is the first report describing resection of an HH for the purpose of treating hyperphagia and obesity.
Garrett K. Zoeller, Carole D. Brathwaite and David I. Sandberg
Optic pathway gliomas (OPGs) arise from the optic nerves, optic chiasm, and/or hypothalamus and most commonly occur in childhood. Although these tumors can be quite challenging to manage, they are typically low-grade astrocytomas histologically, most commonly pilocytic astrocytomas. The few previously reported cases of malignant degeneration of an OPG occurred after external beam radiation therapy. The authors report the first case in the English literature of an OPG that transformed from a low-grade astrocytoma, with features most consistent with a pilocytic astrocytoma, to a malignant glioma without any exposure to radiation therapy.
Anomalous venous drainage preventing safe posterior fossa decompression in patients with Chiari malformation Type I and multisutural craniosynostosis
Report of two cases and review of the literature
David I. Sandberg, Ramon Navarro, Josep Blanch and John Ragheb
✓ The authors report on two children in whom an anomalous posterior fossa venous drainage pattern prevented safe posterior fossa decompression. Both patients had Chiari malformation Type I, multisutural craniosynostosis, and crowded posterior fossa structures. Both patients had been treated with ventriculoperitoneal shunts for hydrocephalus. Pfeiffer syndrome had been diagnosed in one of the patients, and the other was suspected to have osteogenesis imperfecta. Although both patients were believed to have symptoms resulting from brainstem compression, posterior fossa decompression was not offered due to profound venous anomalies noted on imaging studies that greatly increased the expected risks associated with surgery. These cases are presented to alert neurosurgeons to carefully evaluate the posterior fossa venous anatomy prior to considering posterior fossa decompression with or without occipitocervical fusion or calvarial vault remodeling procedures in patients with multisutural craniosynostosis.
Parthasarathi Chamiraju, Sanjiv Bhatia, David I. Sandberg and John Ragheb
The aim of this study was to determine the role of endoscopic third ventriculostomy and choroid plexus cauterization (ETV/CPC) in the management of posthemorrhagic hydrocephalus of prematurity (PHHP) and to analyze which factors affect patient outcomes.
This study retrospectively reviewed medical records of 27 premature infants with intraventricular hemorrhage (IVH) and hydrocephalus treated with ETV and CPC from 2008 to 2011. All patients were evaluated using MRI before the procedure to verify the anatomical feasibility of ETV/CPC. Endoscopic treatment included third ventriculostomy, septostomy, and bilateral CPC. After ETV/CPC, all patients underwent follow-up for a period of 6–40 months (mean 16.2 months). The procedure was considered a failure if the patient subsequently required a shunt. The following factors were analyzed to determine a relationship to patient outcomes: gestational age at birth, corrected age and weight at surgery, timing of surgery after birth, grade of IVH, the status of the prepontine cistern and cerebral aqueduct on MRI, need for a ventricular access device prior to the endoscopic procedure, and scarring of the prepontine cistern noted at surgery.
Seventeen (63%) of 27 patients required a shunt after ETV/CPC, and 10 patients did not require further CSF diversion. Several factors studied were associated with a higher rate of ETV/CPC failure: Grade IV hemorrhage, weight 3 kg or less and age younger than 3 months at the time of surgery, need for reservoir placement, and presence of a normal cerebral aqueduct. Two factors were found to be statistically significant: the patient's corrected gestational age of less than 0 weeks at surgery and a narrow prepontine cistern on MRI. The majority (83%) of ETV/CPC failures occurred in the first 3 months after the procedure. None of the patients had a complication directly related to the procedure.
Endoscopic third ventriculostomy/CPC is a safe initial procedure for hydrocephalus in premature infants with IVH and hydrocephalus, obviating the need for a shunt in selected patients. Even though the success rate is low (37%), the lower rate of complications in comparison with shunt treatment may justify this procedure in the initial management of hydrocephalus. As several of the studied factors have shown influence on the outcome, patient selection based on these observations might increase the success rate.
Kenneth M. Crandall, Esperanza Pacheco-Jacome and David I. Sandberg
✓ The authors report the case of a 3-year-old boy who presented with neck pain after falling from a low height and who was discharged from the emergency department after imaging studies were noted to be normal. He presented again 2 months later with continued neck pain, and repeated imaging demonstrated a fracture of the odontoid basilar synchondrosis that had not been shown on the initial studies. Based on the normal alignment of his spine and evidence of early bone fusion at the time of his second presentation, he underwent cervical orthosis therapy only. To the authors' knowledge, this is the first reported case of an odontoid synchondrosis fracture in which computed tomography scans were normal at presentation.
David I. Sandberg, Mark A. Edgar and Mark M. Souweidane
Object. Convection-enhanced delivery (CED) can be used safely to achieve high local infusate concentrations within the brain and spinal cord. The use of CED in the brainstem has not been previously reported and may offer an alternative method for treating diffuse pontine gliomas. In the present study the authors tested CED within the rat brainstem to assess its safety and establish distribution parameters.
Methods. Eighteen rats underwent stereotactic cannula placement into the pontine nucleus oralis without subsequent infusions. Twenty rats underwent stereotactic cannula placement followed by infusion of fluorescein isothiocyanate (FITC)—dextran at a constant rate (0.1 µl/minute) until various total volumes of infusion (Vis) were reached: 0.5, 1, 2, and 4 µl. Additional rats underwent FITC—dextran infusion (Vi 4 µl) and were observed for 48 hours (five animals) or 14 days (five animals). Serial (20-µm thick) brain sections were imaged using confocal microscopy with ultraviolet illumination, and the volume of distribution (Vd) was calculated using computer image analysis. Histological analysis was performed on adjacent sections.
No animal exhibited a postoperative neurological deficit, and there was no histological evidence of tissue disruption. The Vd increased linearly (range 15.4–55.8 mm3) along with increasing Vi, with statistically significant correlations for all groups that were compared (p < 0.022). The Vd/Vi ratio ranged from 14 to 30.9. The maximum cross-sectional area of fluorescence (range 9.8–20.9 mm2) and the craniocaudal extent of fluorescence (range 2.8–5.1 mm) increased with increasing Vi.
Conclusions. Convection-enhanced delivery can be safely applied to the rat brainstem with substantial and predictable Vds. This study provides the basis for investigating delivery of various candidate agents for the treatment of diffuse pontine gliomas.
David I. Sandberg, J. Gordon McComb and Mark D. Krieger
The authors analyzed the chemical composition of intracranial arachnoid cyst fluid to gain greater understanding of potential causes of cyst growth.
The authors studied 54 pediatric patients who underwent craniotomies for arachnoid cyst fenestration. Cyst fluid was analyzed and results were compared with expected values (EVs) for cerebrospinal fluid (CSF).
The arachnoid cyst fluid values were as follows: protein (median 37 mg/dl, mean 178.2 mg/dl, and EV 25.6 mg/dl), osmolality (median 284 mOsm/kg, mean 285.5 mOsm/kg, and EV 287.2 mOsm/kg), potassium (median 2.6 mEq/L, mean 2.68 mEq/L, and EV 2.88 mEq/L), sodium (median 140 mEq/L, mean 142.2 mEq/L, and EV 143.3 mEq/L), and chloride (median 122 mEq/L, mean 120.77 mEq/L, and EV 120.3 mEq/L). Median glucose was 51 mg/dl (range 26–98 mg/dl). The median white blood cell count in cyst fluid was 1/mm3, and the median red blood cell (RBC) count was 1.5/mm3. All Gram stains and cultures were negative.
No statistically significant correlations were found between arachnoid cyst fluid protein level and elevated RBC count, patient age, or the subsequent need for a shunt. Elevated RBC count in cyst fluid was also not associated with the subsequent need for a shunt.
Fluid from arachnoid cysts has a chemical composition similar to that of CSF, but some of them have significantly elevated protein levels. The authors hypothesize that elevated protein content may contribute to arachnoid cyst expansion in some patients.