ABSTRACT
Abstract Introduction The vidian canal acts as landmark for the identification of the petrous carotid artery, especially during extended endoscopic endonasal approaches in cranial base surgeries. In order to localize the canal and to understand the relationship of pneumatization of pterygoid process to the type of vidian canal, this study was designed. Objectives The objective was to describe the anatomical relationship of pneumatization of the pterygoid process with types of vidian canal. The length of vidian canal, relationship to medial plate of pterygoid process and relationship to the petrous part of internal carotid artery were evaluated. Methods Head computer tomography scans of 52 individuals for suspected paranasal pathology were studied. The degree of sphenoid sinus pneumatization, pterygoid process pneumatization and types of vidian canal (type 1, 2 and 3) were noted. The length of vidian canal, distance from the plane of medial pterygoid plate and relation of vidian canal to the junction of petrous and Gasserian (ascending) part of internal carotid artery was noted. Results 46 (92%) sphenoid sinuses were of the sellar variety. Out of 104 sides that were studied, 57 sides demonstrated a pneumatised pterygoid process and 47 were not pneumatised. In 49 sides (47.1%) the vidian canal was on the same plane as that of the medial pterygoid plate in the coronal section. The vidian canal partially protruded into the sphenoid sinus (type 2) was the most common type (50.9%), found both on right and left sides. There is a statistically significant association between the pterygoid process pneumatization and occurrence of type 2 and type 3 vidian canal configuration. The average length of the vidian canal was 16.16 ± 1.8 mm. In 96 sides, the anterior end of vidian canal was inferolateral to petrous part of internal carotid artery in the coronal plane. Conclusion Pneumatization of the pterygoid process indicates either type 2 or type 3 vidian canal configuration.
Resumo Introdução O canal vidiano atua como ponto de referência para a identificação da artéria carótida petrosa, especialmente durante abordagens endoscópicas endonasais extensas em cirurgias de base do crânio. Este estudo foi projetado com o objetivo de localizar o canal vidiano e entender a relação da pneumatização do processo pterigoide sobre o tipo de canal. Objetivos Descrever a relação anatômica da pneumatização do processo pterigoide com os tipos de canal vidiano. Foram avaliados o comprimento do canal vidiano, a relação com a placa medial do processo pterigoide e com a porção petrosa da artéria carótida interna. Método Foram estudadas tomografias computadorizadas de 52 indivíduos submetidos a tomografia computadorizada de cabeça por suspeita de doença em seio paranasal. Foram observados o grau de pneumatização do seio esfenoidal, a pneumatização do processo pterigoide e os tipos de canal vidiano (Tipos 1, 2 e 3). Observou-se o comprimento do canal vidiano, a distância do plano da placa pterigoide medial e a relação do canal vidiano com a junção da porção petrosa e gasseriana (ascendente) da artéria carótida interna. Resultados Eram do tipo selar 46 (92%) seios esfenoidais. Dos 104 lados estudados, 57 eram do processo pterigoide pneumatizado e 47 não eram pneumatizados. Em 49 lados (47,1%), o canal vidiano estava no mesmo plano que o da placa pterigoide medial na seção coronal. O canal vidiano em protusão parcial no seio esfenoidal (tipo 2) foi o tipo mais comum (50,9%), encontrado nos lados direito e esquerdo. Houve uma associação estatisticamente significante entre a pneumatização do processo pterigoide e a ocorrência da configuração do canal vidiano tipo 2 e tipo 3. O comprimento médio do canal vidiano foi de 16,16 ± 1,8 mm. Em 96 lados, a extremidade anterior do canal vidiano era inferolateral à porção petrosa da artéria carótida interna no plano coronal. Conclusão A pneumatização do processo pterigoide indica a configuração do canal vidiano tipo 2 ou tipo 3.
ABSTRACT
Background: Foramen Vesalius a small inconsistent foramen in the base of skull for passage of emissary vein from pterygoid plexus of veins to cavernous sinus. Variations in incidence and morphology are reported in literature. The objective of this study as to estimate its incidence in south Indian population and to evaluate the morphometric variations. Materials and Methods: Twenty-two dry skulls belonging to department of anatomy, Azeezia Institute of Medical Sciences, Kollam was studied with respect to base of the skull foramens. Wherever the foramen Vesalius was noted, the specimens were photographed and incidence, laterality was noted. Maximum, minimum and perimeter were noted. Any difference between male and female skulls and differences in right and left side were studied for statistical significance. P<0.05 was considered as significant. Results: We found foramen Vesalius in 40.9% of 44 sides examined. Six skulls had this foramen bilaterally. Three specimens had foramen Vesalius unilaterally and six specimens had it bilaterally. Average diameter of foramen was 1.35 (±0.56) mm from extra cranial aspect. The average diameter and perimeter of foramen in males were significantly lower than females. The average distance between foramen Vesalius and foramen ovale was significantly more in females than in males. Conclusion: Foramen ovale is an inconsistent and asymmetrical foramen in base of skull near foramen ovale. Forty percent of the skulls studied had foramen Vesalius. There is significant difference measurements of right and left side foramens. Considering these variations in infratemporal fossa decreases complications while approaching mandibular nerve and trigeminal ganglion.
ABSTRACT
Background: Ossicular morphology and morphometric considerations play cornerstone importance in reconstructive surgeries. An attempt is made to have an insight into such morphological variations and evaluate the morphometric values of malleus in south Indian population through cadaveric dissection. Materials and methods: 25 human head specimens taken from the dissection hall, after removal of brain and duramater, subarcuate fossa and arcuate eminance of the petrous part of the temporal bone were chipped off with help of fine edged chissel and hammer. With help of bone cutter the tegmen tympani forming the remaining roof was removed, till the middle ear cavity and three ossicles are properly exposed and identified. Results: Malleus height ranged from 6.94 mm to 7.78 mm on both sides with average of 7.37mm on right and 7.51 mm on left. Weight ranged from 16.85 mg to 19.25 mg with average of 18 mg on right side and 18.52 mg on left both side. Length and weight of left malleus bones were statistically more than their right counterparts. Conclusions: Morphologically malleus showed lesser variations in comparison to stapes. The left sided malleus dominated the right sided ones in both length and weight.