ABSTRACT
OBJECTIVE: To introduce our device and procedure of electromagnetic navigation (EMN)-guided radiofrequency thermocoagulation (RFT) in patients with trigeminal neuralgia (TN). METHODS: The EMN system mainly consists of an electromagnetic localizer, a thermoplastic facial mask with fiducial markers, and navigation software. A new surgical interface in which the foramen ovale (FO) and the trigeminal ganglion (TG) were integrated was used. It was applied in three patients with TN. RESULTS: FO was successfully and accurately cannulated on the first attempt by using EMN guidance. During the follow-up period, pain did not reoccur, and appropriate trigeminal sensory paresthesia was elicited. There were no surgery-related complications. CONCLUSION: The EMN system is effective and highly accurate for RFT in patients with primary TN. Our modification of the registration system and surgical interface could make the RFT process more simple and accurate.
Subject(s)
Electrocoagulation/methods , Neuronavigation/methods , Trigeminal Neuralgia/surgery , Analgesics, Non-Narcotic/adverse effects , Analgesics, Non-Narcotic/therapeutic use , Carbamazepine/adverse effects , Carbamazepine/therapeutic use , Computer Systems , Drug Resistance , Electromagnetic Fields , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Masks , Middle Aged , Radio Waves , Tomography, X-Ray ComputedABSTRACT
OBJECTIVE: To study the effect of vertebrae semi-dislocation on the stress distribution in facet joint and interuertebral disc of patients with cervical syndrome using three dimensional finite element model. METHODS: A patient with cervical spondylosis was randomly chosen, who was male, 28 years old, and diagnosed as cervical vertebra semidislocation by dynamic and static palpation and X-ray, and scanned from C(1) to C(7) by 0.75 mm slice thickness of CT. Based on the CT data, the software was used to construct the three dimensional finite element model of cervical vertebra semidislocation (C(4)-C(6)). Based on the model,virtual manipulation was used to correct the vertebra semidislocation by the software, and the stress distribution was analyzed. RESULTS: The result of finite element analysis showed that the stress distribution of C(5-6) facet joint and intervertebral disc changed after virtual manipulation. CONCLUSION: The vertebra semidislocation leads to the abnormal stress distribution of facet joint and intervertebral disc.
Subject(s)
Cervical Vertebrae/injuries , Finite Element Analysis , Intervertebral Disc/physiopathology , Joint Dislocations/physiopathology , Models, Anatomic , Stress, Physiological , Zygapophyseal Joint/physiopathology , Adult , Cervical Vertebrae/physiopathology , Humans , MaleABSTRACT
OBJECTIVE: For fixation, registration, and image-guided navigation, the aim of this study was to evaluate a thermoplastic facial mask with plastic markers in achieving frameless stereotactic radiofrequency thermocoagulation (RFT). STUDY DESIGN: A thermoplastic facial mask was remolded according to each subject's face. Six markers were placed on the surface and 6 inside. Series of 1.25-mm- and 2.5-mm-slice computerized tomography (CT) scans were made to provide radiologic data. During the phantom study, each plastic sphere inside was selected in turn as the target for frameless stereotaxy. The clinical Hartel puncture of the foramen ovale (FO) was imitated using an electromagnetic navigation system. Navigation-guided RFT was tried in 3 patients. RESULTS: The mean location error was 1.29 mm (SD ± 0.39 mm). No significant difference (P > .05) was proven between 1.25-mm and 2.5-mm CT slice acquisition for the image datasets used. The FO punctures in clinical trials were successful and confirmed by CT. CONCLUSIONS: Registration and fixation via a fiducial marker-based thermoplastic facial mask is accurate and feasible for use in navigation-guided RFT.
Subject(s)
Catheter Ablation/instrumentation , Fiducial Markers , Masks , Neuronavigation/instrumentation , Phantoms, Imaging , Trigeminal Neuralgia/surgery , Catheter Ablation/methods , Electromagnetic Phenomena , Female , Humans , Male , Middle Aged , Neuronavigation/methods , Patient Positioning , Plastics , Sphenoid Bone/surgery , Tomography, Spiral ComputedABSTRACT
OBJECTIVE: Cervical vertebra semidislocation was one of major pathological aspects of cervical spondylosis, and it was also the target of manipulation to treat cervical spondylosis. The aim of this study was to combine the technology of three dimensional finite element analysis to investigate the method to construct the cervical vertebra semidislocation model. METHODS: A cervical spondylosis patient (male, 28 years old,176 cm tall, weight 69 kg) was randomly chosen, who was diagnosed cervical vertebra semidislocation by dynamic and static palpation and X-ray,and CT scanned from C1 to C7 by 0.75 mm slice thickness. Based on the CT data, the software was used to construct the three dimensional finite element model of cervical vertebra semidislocation (C4-C6). RESULTS: The model showed the three dimensional changes of vertebra semidislocation clearly. C5 had a three-dimensional abnormal position, which was downward translation for 0.9 mm and clockwise rotation for 4.5 degrees around X-axis. So C5 was diagnosed as hypokinesis-type semidislocation. CONCLUSION: The method to construct the three dimensional finite element model of cervical vertebra semidislocation is reliable, which provide a base study to analyse the mechanism of manipulation to treat vertebra semidislocation.
