Outcomes after Ablation
Of these modern ablative procedures, anterior capsulotomy appears to be the most effective.
The literature suggests that approximately 60% of OCD patients had a therapeutic response (35% YBOCS improvement) to ablative procedures. It may take as long as 3-6 months for the beneficial effects to emerge. Potential side effects include headache, confusion, incontinence, weight gain, fatigue, memory loss, and seizure. Cingulotomies have a relatively low rate of side effects.
deep Brain stimulation
Deep brain stimulation (DBS) for psychiatric illness was tried as early as 1948 when JL Pool used stimulation through an electrode in the caudate nucleus in an attempt to treat a woman with depression and anorexia. In 2009, the American Food and Drug Administration (FDA) approved DBS in OCD even with little data, due to the recognition of the humanitarian need to treat severe OCD refractive to other treatments.
The current OCD DBS procedure is essentially the same as for routine use of DBS for movement disorders. Craniotomy is undertaken under local anesthesia, and patients are typically partially sedated but conscious during surgery. Lead placement, which is typically bilateral, is guided by multimodal imaging and specialized computerized targeting platforms. The most common targets for the placement of the leads are indicated in the Figure 10.2.
Outcomes for DBS: the overall response rate appears to exceed 50% in OCD for some DBS targets.
Side effects include hemorrhage, seizure, superficial infection, worsening of symptoms when DBS is stopped (e.g., due to battery failure), and transient hypomanic symptoms.
if Surgery is Warranted, and Ethical issues Have Been Addressed, should someone Choose Ablative surgery or DBs?
The success rates for both ablative surgery and for DBS appear to be comparable but no direct comparisons studies have been conducted.
The main clinical advantages of DBS over lesion procedures are reversibility and adjustability. If DBS treatment is unsuccessful, the hardware can be explanted with little consequence for the patient. The available data from postmortem examination of brains from patients with implanted electrodes suggest that the pathological changes produced by chronic DBS are limited to minimal gliosis along the electrode tract.
One main disadvantage of DBS compared to radiosurgery is its relatively high cost (~$80,000 versus ~$15,000).
Certain centers around the world have experience with neurosurgical procedures for OCD.
FIGURE 10.2 Main targets for DBS in OCD. NAc = nucleus accumbens, ALIC = anterior limb of the internal capsule, VS = ventral striatum,
STN = subthalamic nucleus, BST = bed nucleus of the stria terminalis,
ITP = inferior thalamic peduncle. Reprinted with permission from de Koning PP, Figee M, van den Munckhof P, Schuurman PR, Denys D. Current status of deep brain stimulation for obsessive compulsive disorder: a clinical review of different targets. Curr Psychiatry Rep.
• de Koning PP, Figee M, van den Munckhof P, Schuurman PR, Denys D. Current status of deep brain stimulation for obsessive compulsive disorder: a clinical review of different targets. Curr Psychiatry Rep. 2011 Aug;13(4):274-82.
Figee M, Wielaard I, Mazaheri A, Denys D. Neurosurgical targets for compulsivity: what can we learn from acquired brain lesions. Neurosci Biobehav Rev. 2013 Mar;37(3):328-39.
Greenberg BD, Rauch SL, Haber SN. Invasive circuitry-based neurotherapeutics: stereotactic ablation and deep brain stimulation for OCD. Neuropsychopharmacology. 2010 Jan;35(1):317-36.