Modified reconstruction of the cistern magna for treatment of syringomyelia with Chiari malformation: clinical analysis of 35 cases / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the surgical approaches, microsurgical techniques and therapeutic effect of modified cistern magna reconstruction for treating of syringomyelia with Chiari malformations.</p><p><b>METHODS</b>The clinical data of 35 patients with syringomyelia complicated by Chiari malformations were retrospectively reviewed, and the patients' chief complaints, presenting symptoms, neurological and radiographic findings, surgical approaches, outcomes, and complications were analyzed.</p><p><b>RESULTS</b>The radiographs revealed type I Chiari in 18 and type II Chiari malformations in these patients. Surgical treatment resulted in symptomatic improvements in 29 patients, and 6 patients showed no obvious changes in the symptoms after the surgery; 3 patients received subarachnoid shunting for syringomyelia. During the follow-up for a mean of 2 years, 32 patients showed obvious clinical improvement, and magnetic resonance imaging demonstrated complete spontaneous resolution of syringobulbia in 25 patients.</p><p><b>CONCLUSION</b>Modified cistern magna reconstruction relieves brainstem compression and restores the pulsatile flow of the cerebrospinal fluid at the cervicomedullary junction. Cerebellar tonsil reduction is performed chiefly by electric coagulation and cauterization combined with subpial resection, and the integrity of the pia mater should be maintained as much as possible to avoid potential adhesion and recurrence. The median foramens and Luschka of the fourth ventricle have to be opened to recover normal CSF circulation. Arachnoidal suspension and placement of a patulous dural graft are also important. Modified reconstruction of the cistern magna can be a good option for treatment of syringomyelia complicated by Chiari malformations.</p>

Whole-range encirclement method versus conventional method for microvascular decompression for treatment of hemifacial spasm / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the efficacy and micromanipulation techniques of microvascular decompression with whole-range encirclement method and the conventional method in 65 cases of hemifacial spasm.</p><p><b>METHODS</b>The data of 65 surgically managed cases of hemifacial spasm were retrospectively analyzed for intraoperative findings, surgical techniques, and the patients' outcomes. Microvascular decompression with the conventional approach was performed in 30 patients (group A), and whole-range encircling method was used in the other 35 patients (group B). The patients were also divided into group C (below 40 years, n=27) and group D (above 40 years, n=38) according to the onset age of the symptom.</p><p><b>RESULTS</b>In these patients, 4 patterns of facial nerve compression were identified: simple contact, contact and indentation, adhesion and encasement, and unidentified offending vessels. The offending vessels included the arteries, veins, and vascular loops. In most patients in group C, the arachnoid membrane around the facial nerve thickened and encircled the offending ve;ssel; in group D, the characteristic changes of the vasculature occurred in the offending artery, resulting in its displacement. In groups A and B, the overall efficacy rate was 80% and 97.1%, with recurrence rates of 13.3% and 2.9%, respectively. The major permanent complications in group A included hearing impairment (10.0%) and ataxia (6.7%), whose incidences in group B were 2.9% and 2.9%, respectively.</p><p><b>CONCLUSION</b>Microvascular decompression with whole-range encircling method is a safe approach associated with high cure rate, in which careful avoidance of injuries to the cranial nerves and the penetrating vessels from the root entry/exit zone and the pons ensure good outcome and minimize the likeliness of recurrence and complications.</p>