Endoscopic surgery has revolutionized surgery of the ventral skull base but has not yet been widely adopted for use in the cerebellopontine angle. Given the relatively normal anatomy of the cerebellopontine angle in patients with trigeminal neuralgia (TN), the authors hypothesized that a fully endoscopic microvascular decompression (E-MVD) might provide pain outcomes equivalent to those of microscopic MVD (M-MVD) but with fewer complications.
The authors conducted a single-institution, single-surgeon retrospective study with patients treated in the period of 2006–2013. Before surgery, all patients completed a questionnaire that included a validated multidimensional pain-outcome tool, the Penn Facial Pain Scale (PFPS, formerly known as Brief Pain Inventory–Facial), an 11-point scale that measures pain intensity, interference with general activities of daily living (ADLs), and facial-specific ADLs. Using a standardized script, independent research assistants conducted follow-up telephone interviews.
In total, 167 patients were available for follow-ups (66.5% female; 93 patients underwent M-MVD and 74 underwent E-MVD). Preoperative characteristics (i.e., TN classification, PFPS components, and medication use) were similar for the 2 surgical groups except for 2 variables. Patients in the M-MVD group had slightly higher incidence of V3 pain, and the 2 groups differed in the date of surgery and hence in the length of follow-up (2.4 years for the M-MVD group and 1.3 years for the E-MVD group, p < 0.05). There was a trend toward not finding neurovascular conflict at the time of surgery more frequently in the M-MVD than in the E-MVD group (11% vs 7%, p = 0.052). Internal neurolysis was more often performed in the E-MVD group (26% vs 7%, p = 0.001). The 2 groups did not significantly differ in the length of the MVD procedure (approximately 2 hours). Self-reported headaches at 1 month postoperatively were present in 21% of the patients in the M-MVD group versus 7% in the E-MVD group (p = 0.01). Pain outcomes at the most recent followup were equivalent, with patients reporting a 5- to 6-point (70%–80%) improvement in pain intensity, a 5-point (85%) improvement in pain interference with ADLs, and a 6-point (85%) improvement in interference with facial-specific ADLs. Actuarial freedom from pain recurrence was equivalent in the 2 groups, with 80% pain control at 3 years.
Both the fully endoscopic MVD and the conventional M-MVD appear to provide patients with equivalent pain outcomes. Complication rates were also similar between the groups, with the exception of the rate of headaches, which was significantly lower in the E-MVD group 1 month postoperatively.