The anatomic analysis of the vidian canal and the surrounding structures concerning vidian neurectomy using computed tomography scans / Avaliação anatômica do canal vidiano e estruturas adjacentes por tomografia computadorizada para a neurectomia do vidiano

Abstract Introduction: The type of endoscopic approach chosen for vidian neurectomy can be specified by evaluating the vidian canal and the surrounding sphenoid sinus structures. Objective: The variations and morphometry of the vidian canal were investigated, focusing on the functional correlations between them which are crucial anatomical landmarks for preoperative planning. Methods: This study was performed using paranasal multidetector computed tomography images that were obtained with a section thickening of 0.625 mm of 250 adults. Results: The distributions of 500 vidian canal variants were categorized as follows; Type 1, within the sphenoid corpus (55.6%); Type 2, partially protruding into the sphenoid sinus (34.8%); Type 3, within the sphenoid sinus (9.6%). The pneumatization of the pterygoid process is mostly seen in vidian canal Type 2 (72.4%) and Type 3 (95.8%) (p < 0.001). The mean distances from the vidian canal to the foramen rotundum and the palatovaginal canal were greater in the vidian canal Type 2 and 3 with the pterygoid process pneumatization (p < 0.001). The prevalence of the intrasphenoid septum between the vidian canal and the vomerine crest and lateral attachment which ending on carotid prominence were much higher in vidian canal Type 3 than other types (p < 0.001). The mean angle between the posterior end of the middle turbinate and the lateral margin of the anterior opening of the vidian canal was measured as 33.05 ± 7.71°. Conclusions: Preoperative radiologic analysis of the vidian canal and the surrounding structures will allow surgeons to choose an appropriate endoscopic approach to ensure predictable postoperative outcomes.

Resumo Introdução: O tipo de abordagem endoscópica para a neurectomia do vidiano pode ser definido pela avaliação do canal do vidiano e das estruturas adjacentes aos seios esfenoidais. Objetivo: Investigar as variações e a morfometria do canal vidiano com enfoque nas suas correlações funcionais, pois são parâmetros anatômicos cruciais para o planejamento pré-operatório. Método: Esse estudo foi realizado utilizando-se imagens de tomografia computadorizada multidetectores dos seios paranasais com espessura de corte de 0,625 mm obtidas de 250 indivíduos adultos. Resultados: A distribuição das 500 variantes do canal vidiano foi categorizada da seguinte forma: Tipo 1, dentro do corpo ósseo esfenoidal (55,6%); Tipo 2, protrusão parcial no interior do seio esfenoidal (34,8%); Tipo 3, no interior do seio esfenoidal (9,6%). A pneumatização do processo pterigoide foi observada principalmente no canal vidiano Tipo 2 (72,4%) e Tipo 3 (95,8%) (p < 0,001). As distâncias médias do canal vidiano até o forame redondo e o canal palatovaginal foram maiores no canal vidiano do Tipo 2 e 3, com a pneumatização do processo pterigoide (p < 0,001). A presença do septo intraesfenoidal entre o canal vidiano e a crista vomeriana e a extensão lateral, que termina na proeminência da carótida, foi muito maior no canal vidiano Tipo 3 do que nos outros tipos (p < 0,001). A angulação média entre a cauda da concha média e a margem lateral da abertura anterior do canal vidiano foi de 33,05° ± 7,71°. Conclusões: A análise radiológica pré-operatória do canal do vidiano e das estruturas circunjacentes permitem ao cirurgião escolher uma abordagem endoscópica apropriada e prever resultados pós-operatórios.

Posterior nasal neurectomy in treatment of intractable rhinitis: A preliminary series

Objective@#To evaluate the efficacy and safety of posterior nasal neurectomy on the treatment of nasal congestion, rhinorrhea, sneezing, and post-nasal discharge in intractable rhinitis patients.@*Methods@#Design: Preliminary case series. Setting: Tertiary University Medical Center. Participant: Ten (10) patients with intractable rhinitis underwent endoscopic posterior nasal neurectomy in both sides. Symptoms were compared pre- and post-operatively one month and one year after surgery using Visual Analog Scale (VAS) scores. Endoscopic pre- and one-month post-operative Lund-Mackay scores were also compared.@*Results@#All four mean nasal symptom scores were reduced significantly at 1-month follow-up for nasal congestion (1.5 ± 1.08 vs 4.1 ± 0.5687, p = .00001), rhinorrhea (0.7 ± 0.823 vs 3.4 ± 0.966, p = .00001) post-nasal discharge (0.9 ± 0.994 vs 2.4 ± 1.5, p = .03), and sneezing (1.1 ± 0.738 vs 3 ± 0.943, p = .02). Mean endoscopic scores were also reduced significantly at one month, from 12.9 ± 2.55 to 4.2 ± 3, p = 0.0001.In the 6 patients that followed up at 1-year, post-operative mean nasal symptoms were still significantly better for congestion (0.6667 ± 0.8165 vs 4 ± 0.632, p = 0.00001), rhinorrhea (0.6667 ± 0.5164 vs 3.67 ± 1.033, p = .001), post-nasal discharge (0.1667 ± 0.40825 vs 2.17 ± 1.835, p = .033), sneezing (0.5 ± 0.54772 vs 3.17 ± 0.983, p = 0.0001). Mean post-operative VAS nasal scores and endoscopic scores were well associated (Correlation Coefficient -.648, p = .048).@*Conclusion@#Posterior nasal neurectomy could be considered as a safety and effective way to treat intractable rhinitis patients in Vietnam.