Microvascular decompression: is routine postoperative CT imaging necessary?

Background: Postoperative head CT imaging is routinely performed for detection of postoperative complications following intracranial procedures. However, it remains unclear whether with regard to radiation exposure, costs, and possibly lack of consequences this practice is truly justified in various operative procedures. The objective of this study was to analyze whether routine postoperative CT imaging after microvascular decompression (MVD) is necessary or whether it may be abandoned.

Methods: A series of 202 MVD surgeries for trigeminal neuralgia (179), hemifacial spasm (17), vagoglossopharyngeal neuralgia (2), paroxysmal vertigo (2), and pulsatile tinnitus (2) operated by the senior surgeon (JKK) and who had postoperative routine CT imaging was analyzed.

Results: Routine postoperative CT imaging detected small circumscribed postoperative hemorrhage in 9/202 (4.4%) instances. Hemorrhage was localized at the site of the Teflon felt (1/9), the cerebellum (4/9), in the frontal subdural space (3/9), and in the frontal subarachnoid space (1/9). In two patients, asymptomatic hemorrhage was accompanied by mild cerebellar edema (1%), and another patient had mild transient hydrocephalus (0.5%). Furthermore, there were small accumulations of intracranial air in 86/202 instances. No other complications such as infarction or skull fracture secondary to fixation with the Mayfield clamp were detected. MVD had been performed for trigeminal neuralgia in 6/9 patients, for hemifacial spasm in 2/9, and in one patient with both. No patient underwent a second surgery. Hemorrhage was symptomatic at the time of imaging in only one instance who had mild postoperative gait ataxia. Two patients with hemorrhage developed delayed facial palsy most likely unrelated to hemorrhage which remitted with corticosteroid treatment. At 3-month follow-up and at long-term follow-up, they had no neurological deficits.

Conclusion: Routine postoperative CT imaging is not necessary after MVD in a standard setting in patients who do not have postoperative neurological deficits.