Utility of diffusion tensor-imaged (DTI) motor fiber tracking for the resection of intracranial tumors near the corticospinal tract

Acta Neurochir. DOI 10.1007/s00701-010-0817-0

Treatment of intracranial tumors near the corticospinal tract remains a surgical challenge. Several technical tools to map and monitor the motor tract have been implemented. The present study aimed to assess the utility of diffusion tensor imaging (DTI) fiber tracking in the surgical treatment of motor eloquent tumors at our institution.

Methods Patients operated for intracranial tumors close to the motor tract with the use of intraoperative image guidance including DTI fiber tracking of the corticospinal tract and intraoperative motor evoked potential (MEP) monitoring were analyzed. The intraoperative utility of fiber tracking data was analyzed. Furthermore, preoperative MRI scans with and without motor fiber tracking were reevaluated post hoc for tumor relation to the motor tract, estimated resectability, and best approach. Thereby, the utility of fiber tracking in surgical planning was assessed.

Results Nineteen patients were analyzed. The estimation of tumor localization in relation to the motor tract and of resectability was not influenced by fiber tracking in any of the cases. Only in one single case did evaluating surgeons change their surgical approach after the addition of the fiber tracking data. In all cases, fiber tracking included in image guidance did not change the intraoperative strategy, while MEP monitoring did.

Conclusions DTI fiber tracking did not influence the surgical planning or the intraoperative course. However, it is still used at our institution due to its ease in acquisition and its potential impact in a larger series. Furthermore, more experience with this technique is required to lead to a technical improvement.

A Multicenter Multinational Registry for Assessing Ventriculoperitoneal Shunt Infections for Hydrocephalus

Neurosurgery 67:1303–1310, 2010 DOI: 10.1227/NEU.0b013e3181f07e76

Reported infection rates after ventriculoperitoneal shunt surgery vary from 1 to 25%. Antibiotic-impregnated (AI) catheters may reduce shunt infection rates, but this is uncertain.

OBJECTIVE: To establish a prospective shunt registry to evaluate short-term (3-month) infection rates associated with ventriculoperitoneal shunts and standard or AI catheters during surgical treatment of hydrocephalus.

METHODS: A prospective, multicenter, noncontrolled, open-label registry investigated patients with de novo catheter implantation or catheter replacement of an existing ventriculoperitoneal shunt. The primary outcome was shunt infection.

RESULTS: A total of 440 patients were entered into the registry at 10 sites: 3 in North America, 2 in Singapore, 4 in China and 1 in India. Seven patients were excluded. Of the 433 remaining patients, 314 had new shunts and 119 were revisions. Shunt infections occurred in 14 of 433 patients (3.2%) overall and in 2 of 37 infants (5.2%) younger than 1 year. AI catheters were used in 46 of 433 patients at 7 centers. The shunt infection rate was 0 of 46 for shunts with AI catheters and 14 of 387 (3.6%) without AI catheters. Infection rates were similar with AI catheters, adjusting for age and catheter type.

CONCLUSION: The overall shunt infection rate was lower than in previous multicentered studies. The low infection rate and low rate of AI catheter use precludes any meaningful statement regarding the value of AI catheters in reducing the infection rate. Consideration should be given to performing a well designed, adequately powered, prospective randomized controlled trial to determine whether AI catheters reduce shunt infection rates.