Most Relevant Epidemiological, Clinical, and Imaging Characteristics in a Series of 80 Dominican Patients Affected by Refractory Trigeminal Neuralgia Treated with Stereotactic Radiosurgery Using Gamma Knife.

• DOI: https://doi.org/10.22533/at.ed.1595332528104

• Palavras-chave: Refractory Trigeminal Neuralgia, Neurovascular Conflict, Atrophy, Dystrophy, Trigeminal Eutrophy

• Keywords: Refractory Trigeminal Neuralgia, Neurovascular Conflict, Atrophy, Dystrophy, Trigeminal Eutrophy

• Abstract:

  Objectives: To determine the most relevant epidemiological, clinical, imaging, and structural characteristics of 80 Dominican patients affected by refractory trigeminal neuralgia treated consecutively at the Dominican  Gamma Knife Center over an 8-year period.  Material and Method: Retrospective study of 80 patients (47 women, 33 men) with refractory trigeminal neuralgia treated at the Dominican Gamma Knife Center between March 2011 and March 2019. All patients underwent a 1.5 Tesla MRI scan with 1-1.5 mm slices for three-dimensional reconstruction, including the following sequences: FIESTA, T1 without and with contrast, FLAIR, T2, and TOF. In addition to their epidemiological characteristics, the etiological type of neuralgia (essential or secondary), side of symptoms, affected branch(es), size of the trigeminal cistern (large, intermediate, small), nerve trophicity (eutrophic, atrophic, dystrophic), the presence or absence of neurovascular conflict with precision of side (homolateral or contralateral to the pain), affected trigeminal segment (proximal, intermediate, distal), caliber of the compromised artery (small, medium, large), correlation of trigeminal trophicity with respect to the presence or absence of neurovascular conflict and arterial caliber.    The images were examined by the Principal Investigator (PI) on the Elekta Gamma Plan 11 stereotactic image management platform at the Dominican Gamma Knife Center. The data collected was processed using measures of central tendency and Pearson's correlation-dispersion coefficient on the Microsoft Excel 2016 platform. Results: Women predominated in our population (58.75% vs. 41.25%). The prevalent age range was between 50 and 79 years (71.25%). Essential trigeminal neuralgia (72%) was more frequent than secondary trigeminal neuralgia (28%). The right side (57.5%) was more affected than the left (42.5%). The most affected isolated branch was the upper maxillary (15.69%). The most frequent combination of branches was upper maxillary with lower maxillary (29.41%). Large trigeminal cisterns predominated (66.25% right, 72.5% left) over intermediate cisterns (25% on both sides). Most symptomatic nerves were atrophic or dystrophic. In contrast, unaffected nerves were predominantly eutrophic. Although the symptoms were always unilateral, the presence of neurovascular conflict was detected bilaterally in 75% of cases. The artery causing the conflict was of medium caliber in more than 50% of cases; it was only large caliber in 5% of cases on the right and

  in 3.75% of cases on the left side. On both sides, the proximal segment of the trigeminal nerve was the most frequent site of neurovascular conflict. Trigeminal atrophy was more frequent with larger arterial caliber. Conclusion: This is the first time that a large group of Dominican patients affected by refractory trigeminal neuralgia has been reported in the international medical literature. A detailed analysis of their epidemiological, clinical, and imaging characteristics is presented to facilitate comparison with other published series. Particular emphasis is placed on the size of the trigeminal cistern, the trophicity of the nerves studied, the type of artery involved in the neurovascular conflict, its location, and its impact on the morphology of the trigeminal nerve, aspects for which there is little data in the specialized literature on the subject.