Laser speckle imaging to improve clinical outcomes for patients with trigeminal neuralgia undergoing radiofrequency thermocoagulation.
OBJECTIVE
Percutaneous treatments for trigeminal neuralgia are safe, simple, and effective for achieving good pain control. Procedural risks could be minimized by using noninvasive imaging techniques to improve the placement of the radiofrequency thermocoagulation probe into the trigeminal ganglion. Positioning of a probe is crucial to maximize pain relief and to minimize unwanted side effects, such as denervation in unaffected areas. This investigation examined the use of laser speckle imaging during probe placement in an animal model.


METHODS
This preclinical safety study used nonhuman primates, Macaca nemestrina (pigtail monkeys), to examine whether real-time imaging of blood flow in the face during the positioning of a coagulation probe could monitor the location and guide the positioning of the probe within the trigeminal ganglion.


RESULTS
Data from 6 experiments in 3 pigtail monkeys support the hypothesis that laser imaging is safe and improves the accuracy of probe placement.


CONCLUSIONS
Noninvasive laser speckle imaging can be performed safely in nonhuman primates. Because improved probe placement may reduce morbidity associated with percutaneous rhizotomies, efficacy trials of laser speckle imaging should be conducted in humans.
Department of Neurological Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland.
Matthias
M
Ringkamp
Department of Neurological Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland.
Matthew
M
Wooten
Department of Neurological Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland.
Benjamin S
BS
Carson
Department of Neurological Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland.
Michael
M
Lim
Department of Neurological Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland.
Timothy
T
Hartke
Department of Neurological Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland.
Michael
M
Guarnieri
D000818:Animals; D004564:Electrocoagulation / Q000379:methods*; D005145:Face / Q000033:anatomy & histology / Q000098:blood supply / Q000294:innervation; D005260:Female; D007834:Lasers; D008254:Macaca nemestrina; D008297:Male; D009339:Needles; D059906:Neuroimaging / Q000379:methods*; D019635:Neurosurgical Procedures / Q000379:methods*; D011846:Radio Waves; D012039:Regional Blood Flow; D019051:Rhizotomy; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome; D012668:Trigeminal Ganglion / Q000033:anatomy & histology / Q000098:blood supply / Q000601:surgery; D014277:Trigeminal Neuralgia / Q000601:surgery*
LASCA = laser speckle contrast analysis; ROI = region of interest; TGN = trigeminal neuralgia; functional neurosurgery; laser speckle imaging; multiple sclerosis; pain; preclinical safety study; radiofrequency thermocoagulation; trigeminal neuralgia