Introduction: Trigeminal pain syndromes including classic neuralgia remain a challenge both diagnostically and therapeutically. In some cases of intractable trigeminal pain where microsurgical vascular decompressive (MVD) surgical exploration has been employed there were no cross compressive vessels identified. While there have been a variety of strategies applied to this challenging therapeutic dilemma, little has been written about tractotomy as a treatment for intractable facial pain.
Methods: We present a series of 40 patients who underwent posterior fossa MVD. Two subgroups of patients were identified: 1) patients that we believed would benefit from MVD based on preoperative imaging and at the time of surgery no compressive vessel was found and 2) a heterogenous collection of patients with atypical facial pain that had clinical symptoms suggestive of trigeminal neuralgia (TN). Patients in both groups had tractotomies of the spinal tract of the trigeminal nerve. Diffusion tensor imaging (DTI) was performed on select patients pre-operatively and postoperatively. Postoperative DTI demonstrated a disruption of the spinal tract of the trigeminal nerve.
Results: Patients with evidence of vascular compression of the trigeminal nerve on imaging studies that do not have obvious vessel compression at the time of surgery have a 75% chance of pain relief for 2.25 years. We found that patients that experienced atypical facial pain syndromes (including multiple sclerosis) required subsequent multiple MVD regardless of the addition of ventral tractotomy, additional medications, and had shorter intervals of pain free periods.
Conclusions: The use of DTI may be useful in post-operative outcome analysis for patients with persistent or incomplete resolution of pre-operative facial pain with regard to subsequent management and potential for further ventral tractotomy.
Patient Care: Establish a paradigm for future surgical management of patients with intractable facial pain that exhibit persistent symptoms. It will also serve to add to a small body of literature that can elucidate the use of ventral tractotomy in cases where an obvious compressive vessel is not identified at the time of MVD surgery.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of the role of ventral tractotomy for TN and atypical facial pain and 2) Understand the utility of DTI in postoperative trigeminal neuralgia management.
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