Patient Pain Sketches Can Predict Surgical Outcomes in Trigger-Site Deactivation Surgery for Headaches.

Background: Patient selection for headache surgery is an important variable to ensure successful outcomes. In the authors' experience, a valuable method to visualize pain/trigger sites is to ask patients to draw their pain. The authors have found that there are pathognomonic pain patterns for each site, and typically do not operate on patients with atypical pain sketches, as they believe such patients are poor surgical candidates. However, a small subset of these atypical patients undergo surgery based on other strong clinical findings. In this study, the authors attempt to quantify this clinical experience. Methods: Patients were prospectively enrolled and completed pain sketches at screening. One hundred six diagrams were analyzed/categorized by two independent, blinded reviewers as follows: (1) typical (pain over nerve distribution, expected radiation); (2) intermediate (pain over nerve distribution, atypical radiation); or (3) atypical (pain outside of normal nerve distribution, atypical radiation). Preoperative and postoperative Migraine Headache Index was compared between subgroups using unpairedttests. Results: Migraine Headache Index improvement was 73 +/- 38 percent in the typical group, 78 +/- 30 percent in the intermediate group, and 30 +/- 40 percent in the atypical group. There was a significant difference in Migraine Headache Index between the typical and atypical groups (p= 0.03) and between the intermediate and atypical groups (p< 0.01). The chance of achieving Migraine Headache Index improvement greater than 30 percent in the atypical group was 20 percent. Conclusions: Patient pain sketches classified as atypical (facial pain, atypical pain point origin, diffuse pain) can predict poor outcomes in headache surgery. As the authors continue to develop patient selection criteria for headache surgery, patient sketches should be considered as an effective, cheap, and simple-to-interpret tool for selecting candidates for surgery.