Clinical Trial Details
— Status: Enrolling by invitation
Administrative data
NCT number |
NCT05659082 |
Other study ID # |
1909-001 |
Secondary ID |
|
Status |
Enrolling by invitation |
Phase |
Phase 3
|
First received |
|
Last updated |
|
Start date |
June 21, 2022 |
Est. completion date |
December 31, 2032 |
Study information
Verified date |
January 2023 |
Source |
Butler Hospital |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Obsessive-compulsive disorder impacts 1-2 percent of the population. Unfortunately, about
fifteen percent of patients fail to benefit from existing therapies. A small number of OCD
patients, who have a disabling illness that does not improve after conventional treatments,
have neurosurgery as a last resort. One procedure, capsulotomy, involves making pairs of
lesions in an anatomically-defined part of the anterior limb of the internal capsule, a
structure containing nerve fiber bundles connecting the thalamus, in the center of the brain,
to the prefrontal cortex, the most anterior and outermost brain region. The investigators
will examine how the therapeutic effects of capsulotomy relate to changes in the structure of
these brain pathways with structural (diffusion tensor imaging, DTI) and functional
(resting-state and task-based) connectivity metrics. The investigators will also utilize
experimental cognitive tasks that are sensitive to the circuitry impacted by this procedure.
Description:
Obsessive-compulsive disorder (OCD) is a common condition. One to two percent of the
population experiences the chronic intrusive obsessive thoughts, repetitive compulsions, and
pathological anxiety characteristic of the illness, which by several measures is among the
ten most disabling medical conditions for adults in industrialized countries. Unfortunately,
about fifteen percent of patients fail to benefit from existing therapies. A small number of
OCD patients, who have a disabling illness that does not improve after conventional
treatments, have neurosurgery as a last resort. One procedure, capsulotomy, involves making
pairs of lesions in an anatomically-defined part of the anterior limb of the internal
capsule, a structure containing nerve fiber bundles connecting the thalamus, in the center of
the brain, to the prefrontal cortex, the most anterior and outermost brain region. OCD is
believed to result from abnormal activity in brain circuits connecting the prefrontal cortex,
thalamus and other brain areas. Data show that approximately 50 to 60 percent of patients
improve after capsulotomy.
In addition, new neuroimaging measures of how brain fiber tracts and the brain regions
associated with them change after capsulotomy promise to enhance the understanding of OCD
pathophysiology, and may help advance capsulotomy and other neuroanatomically-based
therapies. While capsulotomy is believed to exert its therapeutics effects by changing
thalamus-prefrontal cortex connections, the specific anatomical changes produced by this
surgical treatment in these fiber pathways are unknown. This is especially true at greater
distances from the site of surgery, that is, closer to the thalamus and prefrontal cortex,
the regions the surgery is intended to partially disconnect from each other. The
investigators will examine how the therapeutic effects of capsulotomy relate to changes in
the structure of these brain pathways with structural (diffusion tensor imaging, DTI) and
functional (resting-state and task-based) connectivity metrics. Additional measures of how
brain volumes may change in specific corticobasal structures implicated in OCD (including the
basal ganglia, thalamus, and orbitofrontal cortex) will be derived from conventional MRI
measures obtained during the same sessions when the experimental DT-MRI measures are
acquired. The investigators will also utilize experimental cognitive tasks that are sensitive
to the circuitry impacted by this procedure.
Understanding the changes after surgery that result in the best therapeutic outcomes will
allow the investigators to improve capsulotomy as a treatment for this debilitating disease.
With this information, the investigators can refine the targeting of capsulotomy for
individual patients and, possibly, aid the development of other treatments, including deep
brain stimulation, for intractable OCD. This study provides a unique opportunity to test
structural and functional connectivity measures as probes of complex neuronal circuits that
are likely to be involved in psychiatric illness.