Ablative neurosurgery for movement disorders related to cerebral palsy.

This article aims to describe the roles, operative strategies and outcomes of neuroablative procedures in treatment of movement disorders related to cerebral palsy (CP). The authors reviewed relevant medical literatures concerning ablative neurosurgical procedures for CP. Neurosurgery is an appropriate option for treatment of intractable movement disorders in CP. Destructive therapies can be selectively operated upon, on the brain, spinal cord, nerve root and peripheral nerve. Because all of them carry irreversible properties, presurgical evaluation and decision making for the surgery are critical. Selection of the procedures should be tailored for individual cases. Selective dorsal rhizotomy (SDR) is mostly suitable for CP children with spastic diplegia who are potential ambulators. Selective peripheral neurotomy (SPN) aims to diminish localized hypertonia. Intractable painful spasticity in an entire useless limb can be effectively treated by dorsal root entry zone lesion (DREZotomy). Stereotactic coagulation of specific targets in the brain is appropriate for more diffuse movement disorders or hyperkinesias confined to one side of the body. Combined surgery should be employed in management of more complicated abnormalities or coexisting neurologic and orthopedic disorders. Neuroablation remains an alternative to neuromodulation therapy, especially in circumstances when the latter is unavailable.

A new technique for the repair and reconstruction of frontoethmoidal encephalomeningoceles by medial orbital composite-unit translocation.

A frontoethmoidal encephalomeningocele is a herniation of brain and meninges through a congenital bone defect in the skull at the junction of the frontal and ethmoidal bones. Between 1992 and 1999, we treated 145 cases of frontoethmoidal encephalomeningocele. Before 1993, the operation was performed in two stages. An intracranial repair by neurosurgeons preceded the external extirpation of the mass. In 70 cases that were operated on after 1993, a one-stage closure of the skull defect with a medial orbital composite-unit translocation technique was used. The medial orbital rim on each side, with intact periosteum, medial canthal ligament and lacrimal apparatus, was translocated as a unit to the midline. The advantages of this technique are that it allows convenient access to resect the herniation mass and close the defect, it restores normal interorbital and intercanthal distances and it eliminates the need for a transnasal medial canthopexy. Augmentation rhinoplasty can be avoided in most cases by tilting the composite unit with its preserved blood supply.

Aetiology of delayed facial palsy after vestibular schwannoma surgery: clinical data and hypothesis.

A patient developed delayed facial nerve palsy at the level of House-Brackmann grade I to grade III 10 days after vestibular schwannoma surgery by the suboccipital transmeatal approach. The palsy had completely recovered after one month. Immunological study showed reactivation of herpes simplex and magnetic resonance (MR) imaging demonstrated an abnormal enhancement pattern of the facial nerve; intense enhancement of the distal intracanalicular segment and labyrinthine segment, similar to the MR findings for Bell's palsy. A prospective control study on the enhancement pattern of the functionally preserved facial nerve after vestibular schwannoma surgery in six cases showed a similar pattern to that of the normal facial nerve. Based on these findings, we propose the hypothesis that herpes simplex reactivation is an underlying cause of delayed facial palsy after vestibular schwannoma surgery.

Morphologic study of 120 skull base defects in frontoethmoidal encephalomeningoceles.

Frontoethmoidal encephalomeningocele is a herniation of brain and meninges through a congenital bone defect in the skull at the junction of the frontal and ethmoidal bones. From 1992 to 1996, 120 cases of frontoethmoidal encephalomeningocele were seen in our institutes, and the morphology of the skull defects was studied. The patients underwent thorough physical examinations and radiographic investigations including spiral three-dimensional computed tomography scan. Together with intraoperative findings, we found more types of the defects than previously reported. Our findings were categorized into the following types: type I, a single external opening between frontal, nasal, ethmoidal, and orbital bones; type IA, opening is limited between two bones of the area; type IB, opening is extended transversely or cephalad to involve adjacent structures; type II, multiple external openings in the region; type IIA, all of the openings are limited types; type IIB, one or more of the openings is/are extended type(s) that involve adjacent structures. There are 14 subtypes in these two types: 3 in type IA, 6 in type IB, 3 in type IIA, and 2 in type IIB. This classification is helpful in understanding the herniation pathway and in keeping informative records.