William C. Gump

Selective dorsal rhizotomy for spasticity not associated with cerebral palsy: reconsideration of surgical inclusion criteria

Children with spastic diplegia from cerebral palsy (CP) experience measurable improvement in their spasticity and motor function following selective dorsal rhizotomy (SDR). The role of this operation in the treatment of other spasticity causes is less well defined. A literature review was undertaken to survey outcomes from SDRs performed outside the CP population. Multiple sclerosis was the most common diagnosis found, accounting for 74 of 145 patients described. Selective dorsal rhizotomies have also been reported in patients with traumatic brain and spinal cord injuries, ischemic and hemorrhagic stroke, neurodegenerative disease, hypoxic encephalopathy, and other causes of spasticity. Outcomes from surgery are generally described as favorable, although postoperative assessments and follow-up times are not standardized across reports. Long-term outcomes are sparsely reported. Larger numbers of patients and more detailed outcomes data have the potential to form a basis for expanding the inclusion criteria for SDR.

Complications associated with molding helmet therapy for positional plagiocephaly: a review

Molding helmet therapy is a widely accepted treatment for positional plagiocephaly that is generally considered to be low risk. Multiple large outcome studies have shown good results, but adverse events are rarely reported. The literature on helmet therapy was reviewed to clarify the clinical experience with associated complications. Although significant complications were extremely rare, there was a large degree of variability in detection of lesser problems such as minor skin irritation. Patients with a primarily brachycephalic morphology may be at higher risk for poorly fitting orthoses. Most reported complications are minor and self-limited. Maintenance of good helmet hygiene appears to be the most effective strategy for reducing or eliminating complications.

Meningiomas of the pediatric skull base: a review.

Pediatric skull base meningiomas are rare and complex clinical entities. Meningioma is a relatively uncommon brain tumor in children, and only ∼ 27% involve the skull base. Some evidence suggests that these tumors are more likely to be atypical or malignant in children than adults. The absence of female preponderance in pediatric meningiomas is reflected in the skull base subpopulation. Skull base meningiomas in children are most likely to be found in the anterior or middle fossa base, or involving the orbit and optic nerve sheath. Petroclival, suprasellar/parasellar, cerebellopontine angle, cavernous sinus, and foramen magnum tumors are very rare. Meningiomas constitute a small proportion of reported cases of pediatric skull base pathology, and they are entirely absent from many case series. Initial gross total resection is consistently associated with superior outcomes. Surgical approaches to the pediatric skull base must take additional factors into consideration including relatively smaller anatomy, immature dentition, incompletely aerated sinuses and air cells, and altered configurations of structures such as the pterional bony complex. Multidisciplinary expertise is essential to optimizing treatment outcomes.

Seizure control after subtotal lesional resection

Reports on seizure outcomes following surgery for lesional epilepsy consistently cite extent of resection as a significant predictor of outcome. Unfortunately, gross-total resection is not technically feasible in all cases of medically refractory tumor-associated epilepsy. Here, the authors present the case of a 4-year-old girl whose epilepsy was medically controlled after 1-stage electrocorticography-guided subtotal resection (STR) of a large diffuse protoplasmic astrocytoma. They also review the modern literature on epilepsy associated with brain tumors. Outcomes are compared with those following surgical treatment of focal cortical dysplasia and vascular lesions. Gross-total lesional resection shows significant superiority across pathologies and anatomical regions. Despite a considerable number of STRs yielding seizure freedom, other favorable treatment factors have not been defined. Although gross-total lesional resection, if possible, is clearly superior, tailored surgery may still offer patients a significant opportunity for a good outcome. Treatment factors yielding successful seizure control following STR remain to be fully elucidated.

Endoscopic Endonasal Repair of Congenital Defects of the Anterior Skull Base: Developmental Considerations and Surgical Outcomes

Techniques of endoscopic endonasal surgery, initially developed primarily for intracranial neoplasms, have been adapted to treat a wide variety of pathologies previously addressed with open craniotomy including congenital and acquired defects of the anterior skull base. Congenital defects can lead to herniation of leptomeninges containing cerebrospinal fluid alone or with brain tissue. Specific types of encephalocele can be defined on the basis of the associated abnormal bony anatomy. Endoscopic endonasal surgery represents a relatively recent development in the treatment of these entities. Technical considerations include relatively younger age range of the patient population, dimensions of preexisting bony defect, volume of herniated meninges and brain tissue, and distorted anatomy from abnormal development of the affected craniofacial skeleton. Recent highly detailed anatomical studies have quantitatively verified the utility of endoscopic endonasal surgery in the pediatric population. Particular attention has been directed toward adequacy of nasoseptal flap reconstruction in pediatric patients. Several reports have described patients with encephalocele of the anterior cranial fossa successfully treated with endoscopic surgery. The literature on endoscopic repair of congenital encephalocele is reviewed. Outcomes have generally been reported as favorable, although long-term follow-up and systematic studies have not been pursued.

Fibrous Dysplasia of the Temporal Bone: Imaging Characteristics and Neurotologic Considerations

Introduction: Fibrous dysplasia (FD) is a progressive, often indolent bone disorder in which normal bone marrow is replaced by a mixture of fibrous tissue and woven bone. It can potentially involve the long bones, pelvis, and craniofacial bones, either as monostotic or polyostotic disease. FD of the skull most commonly involves the frontal and sphenoid bones. Isolated FD of the temporal bone is relatively rare. Case Report: A 15-year-old boy presented with several weeks of progressive left-sided headaches. He was neurologically intact including facial nerve, hearing, and vestibular examinations. Imaging revealed an extradural left middle fossa lesion appearing to arise from the bones of the inner ear. Temporal bone CT demonstrated that the lesion abutted the geniculate ganglion, the labyrinthine and tympanic segments of CN VII, the superior semicircular canal, and the petrous carotid. The patient was taken to surgery, where radical resection was limited by proximity to the facial nerve, which was adjacent to the field but not compressed. The diagnosis of FD was confirmed by pathology. Postoperatively, the patient developed a delayed House-Brackmann 3 facial droop which was self-limited. Discussion: The etiology of FD is a somatic missense mutation in the gene GNAS1, which encodes the alpha subunit of the stimulatory G protein-coupled receptor Gsα. The mutation leads to constitutive, ligand-independent activation and accumulation of cAMP, similar to the effect of continuous parathyroid hormone stimulation. Studies of the natural history of FD have suggested that the disease becomes inactive after puberty, although as many as one third of patients have recurrence in adulthood. Postpubertal disease progression is observed more commonly in the polyostotic rather than the monostotic disease variant. The incidence of malignant transformation is reported at 0.4%, although sarcomatous transformation has been strongly associated with radiation treatment. Radiologically, three patterns of FD have been described: pagetoid (ground-glass), the most common; sclerotic; and cystic, the least common (10% of cases) and of which the present case is an example. Retroauricular swelling and hearing disturbances are the most common presenting complaints in patients with temporal bone FD. A recent temporal bone FD case series reported eight of nine patients presenting with conductive or sensorineural hearing loss. Radical excision is generally recommended when technically and cosmetically feasible to minimize the risk of disease recurrence. Recurrence rates of 25% have been reported for subtotal resection. Conclusions: Temporal bone fibrous dysplasia can involve the vestibular apparatus, organs of hearing, and the cranial nerve VII-VIII complex. Delayed facial nerve palsy after decompression can have a favorable prognosis. Radical resection may not be necessary for a good outcome.