Kuniaki Nakahara, Masaru Yamada, Satoru Shimizu and Kiyotaka Fujii
✓ This 50-year-old woman presented with headache and visual disturbance. Neuroimaging results demonstrated a well-demarcated tumor attached to the falx cerebri near the transverse sinus, and the lesion was subtotally removed. Based on histological and immunohistochemical evaluation, a solitary fibrous tumor (SFT) was diagnosed. During the next 32 months, the size of the residual tumor increased slightly at the transverse sinus. Stereotactic radiosurgery (SRS) was performed as an adjuvant treatment. Over the course of the next 4 years the tumor decreased in size. The authors suggest that SRS constitutes good adjuvant treatment for regrowing residual SFTs not amenable to reoperation.
Satoru Shimizu, Takao Sagiuchi, Takahiro Mochizuki, Shinichi Kan and Kiyotaka Fujii
Regression of an atlantoaxial degenerative articular cyst associated with subluxation during conservative treatment
Case report and review of the literature
Takao Sagiuchi, Satoru Shimizu, Ryusui Tanaka, Shigekuni Tachibana and Kiyotaka Fujii
✓ The presence of an atlantoaxial degenerative articular cyst is rare; when present this lesion extends posteriorly to the dens, causing cervicomedullary compressive myelopathy. The authors describe a symptomatic case of this lesion associated with atlantoaxial subluxation in a 76-year-old man. The patient’s neurological symptoms resolved and corresponded to a reduction in the size of the cyst. After 8 months of continued conservative treatment, in which the patient wore a Philadelphia collar, the cyst spontaneously regressed. Subsequently, a C1–2 posterior fusion was performed to treat the atlantoaxial subluxation.
Satoru Shimizu, Satoshi Utsuki, Sachio Suzuki, Hidehiro Oka and Kiyotaka Fujii
✓Although the Codman-Hakim programmable valve is popular, several problems arising from its design have been described. The authors report an additional cause of shunt obstruction in the system. A 6-year-old girl who had received a ventriculoperitoneal shunt with the Codman-Hakim programmable valve system presented with worsening consciousness. The valve proved hard to flush, and emergency revision of the valve was performed. Examination of the extracted valve revealed that the pressure control cam had migrated into the outlet of the valve, thus causing the obstruction. A crack in the plastic housing surrounding the cam suggesting a past impact to the system was also revealed. These factors should thus be kept in mind as potential sources of obstruction of the valve system, especially in patients susceptible to episodes of head impact.
Kuniaki Nakahara and Satoru Shimizu
The majority of shunt infections occur within 6 months of shunt placement and chiefly result from perioperative colonization of shunt components by skin flora. Antibiotic-impregnated shunt (AIS) systems have been designed to prevent such colonization. In this study, the authors evaluate the incidence of shunt infection after introduction of an AIS system in a population of children with hydrocephalus.
The authors retrospectively reviewed all pediatric patients who had undergone cerebrospinal fluid (CSF) shunt insertion at their institution over a 3-year period between April 2001 and March 2004. During the 18 months prior to October 2002, all CSF shunts included standard, nonimpregnated catheters. During the 18 months after October 2002, all CSF shunts included antibiotic-impregnated catheters. All patients were followed up for 6 months after shunt surgery, and all shunt-related complications, including shunt infection, were evaluated. The independent association of AIS catheter use with subsequent shunt infection was assessed via multivariate proportional hazards regression analysis.
A total of 211 pediatric patients underwent 353 shunt placement procedures. In the 18 months prior to October 2002, 208 (59%) shunts were placed with nonimpregnated catheters; 145 (41%) shunts were placed with AIS catheters in the 18 months after October 2002. Of patients with nonimpregnated catheters, 25 (12%) experienced shunt infection, whereas only two patients (1.4%) with antibiotic-impregnated catheters experienced shunt infection within the 6-month follow-up period (p < 0.01). Adjusting for intercohort differences via multivariate analysis, AIS catheters were independently associated with a 2.4-fold decreased likelihood of shunt infection.
The AIS catheter significantly reduced incidence of CSF shunt infection in children with hydrocephalus during the early postoperative period (< 6 months). The AIS system used is an effective instrument to prevent perioperative colonization of CSF shunt components.