RESUMEN
The aim of this study is to evaluate cribriform-lamella (CL) angle and length of lateral lamella (LL) on CT scan and to correlate CL angle with LL length and Keros classification. Retrospective study analyzing 500 CT scans of PNS was performed at a tertiary care hospital. The CT scan anatomy of anterior cranial base was evaluated for Keros, CL angle and LL length. The relationship between these measurements was studied. Keros type I (75.2%) was the commonest finding in our study. Males have increased depth of olfactory fossa but there were no differences between the sides. Type A angle of CL (66.1%) was the commonest with females having an increased CL angle as compared to males. The LL length was 3.6 mm (± 0.8). There were no significant difference between sex/side of LL. Keros was found to be strongly correlated with the LL length whereas it has mild negative correlation with CL angle. There was no correlation between CL angle and LL length. Keros classification is the commonest criteria used to assess the risk of injury to anterior cranial base. However, we have found that the CL angle has an important role to play in the angulation/slope/level of anterior cranial base during endoscopic sinus surgery. CL angle needs to be considered as an important factor during endoscopic sinus surgery.
RESUMEN
The aim of this study is to identify a surgical safe zone in base of tongue surgery. Fifteen Fresh frozen cadavers (30 head and neck regions) were included in the anatomical study. Twenty-two CT-angiogram (CTA) scans of neck were included in the radiological study. Surgical safe zone for base of tongue surgery was studied in cadavers and correlated the same in CTA. Depth of the lingual artery (LA) from the tongue surface and distance of origin of lingual artery from tip of greater cornu of hyoid bone was significantly different when comparing anatomical to radiological study (p < 0.005). On protruded position of tongue, lingual artery appeared more close to the tongue surface and was never encountered posterior to foramen caecum. Preoperative CTA evaluation would over-estimate the depth of LA putting the lingual artery at risk during resection. A surgical safe zone exists posterior to foramen caecum and towards the midline.