Capsulotomy in anxiety disorders

Background and aim: Anxiety disorders are common and a substantial proportion of patients do not respond to conventional treatments such as SSRIs or CBT. Capsulotomy is a neurosurgical treatment for treatment refractory patients with Obsessive-Compulsive Disorder (OCD) and other anxiety disorders. The aim of this thesis was to assess the long-term efficacy and safety of capsulotomy.

Methods and results: In Study I, 26 consecutive patients who underwent capsulotomy from 1975-1991 were followed after a mean of 13 years. Main diagnoses were Generalized Anxiety Disorder (n=13), Panic Disorder (n=8) and Social Phobia (n=5). Mean Brief Scale of Anxiety score dropped significantly from preoperative 22 to 10 at long-term. Seven patients had postoperative problems in the domains of executive functioning, apathy or disinhibition. Mean weight gain in the first postoperative year was almost 10 kg. Study II and III were substudies of Study I.

In Study II the capsulotomy lesion size and localization in the anterior-posterior plane was analyzed. We could not replicate previous findings of a common anatomical denominator in the right-sided capsule in patients responding to the treatment. In Study III, we used a self-rated personality inventory, the Karolinska Scales of Personality, to describe changes pre- to postoperatively in self-rated personality. Patients were significantly less anxiety prone at follow-up.

Study IV was a long-term follow-up of 25 consecutive OCD capsulotomies performed 1988 -2000. Mean Y-BOCS was 34 preoperatively and dropped to 18 at long-term follow-up (p<0.0001). Only 2 patients achieved remission from OCD without substantial side effects. Several neurosurgical complications related to radiosurgery were reported. Two patients were severely disinhibited postoperatively. Ten patients were considered to suffer from significant problems in the area of executive functioning, apathy or disinhibition. Global functioning did not return to normal after surgery. Lesion size did not correlate significantly with efficacy or adverse effects.

Conclusions: Capsulotomy is effective in reducing symptoms in both OCD and other anxiety disorders. About every third patient experienced apathy, executive problems or disinhibition at long-term follow up, therefore we conclude that capsulotomy is not a safe procedure. We could not identify lesion characteristics that could explain the differences in outcome. We could not confirm the hypothesis of a certain right-sided lesion as a prerequisite for response to capsulotomy.

List of scientific papers

I. Rück C, Andréewitch S, Flyckt K, Edman, G, Nyman H, Meyerson BA, Lippitz BE, Hindmarsh T, Svanborg P, Mindus P, Åsberg M (2003). Capsulotomy for refractory anxiety disorders: long-term follow-up of 26 patients. Am J Psychiatry. 160: 513-21.
https://doi.org/10.1176/appi.ajp.160.3.513

II. Rück C, Svanborg P, Meyerson BA (2005). Lesion topography in capsulotomy for refractory anxiety--is the right side the right side? Stereotact Funct Neurosurg. 83(4): 172-9.
https://doi.org/10.1159/000089988

III. Rück C, Edman G, Åsberg M, Svanborg P (2006). Long-term Changes in Selfreported Personality following Capsulotomy in Anxiety patients. Nord J Psychiatry. [Accepted]
https://doi.org/10.1080/08039480601022116

IV. Rück C, Karlsson A, Edman G, Ericson K, Nyman H., Meyerson B. A., Åsberg M., Svanborg P (2010). Capsulotomy for OCD: long-term follow-up of 25 patients. [Manuscript]