59.2.1 Pretreatment Headache Prevalence

Pretreatment, there is a wide variability in the prevalence of headache in patients presenting with VS. Studies suggest that 6 to 60% of patients with VS will complain of headache, paralleling the general population.s. Literatur ^,​ s. Literatur The largest series of 1,657 patients with VS reported approximately one-third have preoperative headache.s. Literatur Whether the presence of headache is directly attributable to the tumor or other preexisting headache disorders has not been clarified. The coexistence of headache disorders with VSs has been frequently observed. In a study of 192 patients with VS, Rimaaja and colleagues indicated 24% of patients met International Headache Criteria for migraine, while 9% patients had tension-type headaches.s. Literatur

59.2.2 Postsurgical Headache Prevalence and Risk Factors

The prevalence of headaches postoperatively in patients undergoing craniotomy for VS has been more difficult to study. Retrospective studies often underestimate the prevalence of headache based on what clinical features were recorded in the medical record. Prospective studies may be hindered by recall bias depending on when a patient is assessed relative to the time of surgery (in some studies, up to 15 years postoperatively). Studies also vary in regards to inclusion criteria, with some studies reporting headache outcomes in all patients undergoing VS surgery regardless of the approach and others reporting outcomes only after specific approaches and surgical techniques. In addition, studies vary in their definitions of headache type with few using International Classification of Headache Disorders (ICHD) criteria.

With the limitations noted earlier, postcraniotomy headaches are present in 0 to 75% of patients undergoing surgery for VS (Table 59‑1 ). In about 90% of patients, the headache is noted immediately postoperatively.s. Literatur Many patients improve within 1 to 2 months.s. Literatur About 20 to 30% of these patients have headaches that begin postoperatively, but persist beyond 6 months.s. Literatur ^,​ s. Literatur ^,​ s. Literatur By 1 to 2 years, the prevalence of headache diminishes.s. Literatur ^,​ s. Literatur The persistence of headaches after the retrosigmoid approach for VS has been estimated to be 63% at 6 months, falling to 24% by 1 year and to 12% by 2 years.s. Literatur

In patients undergoing surgery for VS, risk factors for postoperative headache or headache severity include preoperative headache,s. Literatur ^,​ s. Literatur ^,​ s. Literatur retrosigmoid approach,s. Literatur ^,​ s. Literatur craniectomy rather than craniotomy,s. Literatur coexisting anxiety and depression,s. Literatur perioperative complications,s. Literatur and younger age.s. Literatur ^,​ s. Literatur Tumor size was not associated with postoperative headaches. Literatur ^,​ s. Literatur ^,​ s. Literatur ^,​ s. Literatur in some studies, but otherss. Literatur ^,​ s. Literatur ^,​ s. Literatur suggest a small tumor size is associated with higher risk of postoperative headache. Similarly, there is conflicting results on the influence of gender, with some suggesting female sex as a risk factors. Literatur ^,​ s. Literatur and others not. There seems to be no clear correlation of postoperative headache with complete versus partial resection and whether or not the facial or cochlear nerve is preserved.s. Literatur

The prevalence of headache based on surgical approach has also been compared. Early series suggested that the retrosigmoid approach is associated with a higher prevalence of postsurgical headache. In one large meta-analysis of 5,064 patients from 35 studies, complications of VS microsurgery were assessed by approach. In this study, the incidence of postoperative headache was noted in 17.3% who underwent the retrosigmoid approach, 8% in the middle cranial fossa approach, and 0% for the translabyrinthine approach.s. Literatur The study was limited by variable length of follow-up and lack of specific headache definitions. Similarly other studies have reported that the retrosigmoid approach is associated with a higher risk of postoperative headache and/or a higher risk of severe headache.s. Literatur ^,​ s. Literatur ^,​ s. Literatur ^,​ s. Literatur Schessel and colleaguess. Literatur reported a 64% incidence of headache for the retrosigmoid approach, in comparison to 0% for the translabyrinthine approach.

However, studies have not uniformly suggested that surgical approach is a major risk factor for long-term headache.s. Literatur ^,​ s. Literatur The latter results may be due to the timing and manner of surveying patients for these types of studies. Ruckenstein and colleagues evaluated 52 patients for postoperative headache, some of who underwent a suboccipital craniotomy and some of who underwent a translabyrinthine approach.s. Literatur At 1 and 6 months, patients undergoing the suboccipital craniotomy had more severe pain than those who had undergone a translabyrinthine approach. By 1 year, however, there was no difference in the headache severity among these patients. Similarly, Carlson and colleagues did not find a significant difference in long-term headache disability at a mean of approximately 7 years following treatment, when comparing amongst 143 patients who underwent retrosigmoid, translabyrinthine, or middle fossa microsurgical approaches.s. Literatur While it appears that the retrosigmoid approach is associated with more frequent and severe headaches in the early postoperative period, the relationship between surgical approach and long-term headache outcome remains controversial.