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Objective The main objective of the study was to show the morphologic features of optic strut (OS) and prechiasmatic sulcus (PS) in the fetal skull base with a surgical anatomical perspective. Methods Twenty-three fetal cadavers (9 female, 14 male) with an average age of 21.70 ± 3.12 (range: 16–28) weeks of gestation in the inventory of the Anatomy Department were included in the study. Measurements were made with a digital image analysis software and goniometer. Results The sulcal length, interoptic distance, planum length, and sulcal angle were detected as follows: 3.91 ± 0.74 mm, 6.88 ± 1.04 mm, 6.55 ± 1.51 mm, and 24.52 ± 9.51°, respectively. Considering the location of the posteromedial margin of OS according to PS, OS was identified as the sulcal in 56.5% (13 cases), postsulcal in 30.4% (7 cases), and asymmetric in 13% (3 cases). According to the sulcal length and angle, PS was identified as type 1 in 26.1% (6 cases), type 2 in 21.7% (5 cases), type 3 in 30.4% (7 cases), and type 4 in 21.7% (5 cases). Conclusions Our findings suggest that the sulcal length and angle reach adult size in utero. Taking into account the fetal and the gathered adult measurements, the high percentage of steep angle compared to flat angle show that after birth, PS become more flat, probably depending on the variations of the sphenoid sinus pneumatization. Thus, more studies conducted on the alterations in PS and OS types relative to the pneumatization are needed in terms of patient positioning, selection of appropriate surgical approach, and intraoperative decision-making.

Purpose To investigate the characteristics of the prechiasmatic sulcus in children aged between 1–20 years. Methods Patient files of 200 children admitted to the university hospital on 2019 were analyzed, retrospectively. The computed tomography images of patients were used to obtain anatomical knowledge containing prechiasmatic sulcus types and dimensions. Results The measurements related to the sulcal length (6.94 ± 1.25 mm) and sulcal angle (31.01 ± 18.13°) showed that the sulcal length did not alter in children between 1 and 20 years, whereas the sulcal angle did not vary from infancy to prepubescent period, but it was decreasing in postpubescent period. In 29 patients, the sulcal length was observed to divide into 2 parts with an evident angle. The interoptic distance and planum length were found as follows: 14.70 ± 2.85 mm and 14.84 ± 4.12 mm, respectively. The order of PS types was observed as type 4 (26.5%, 53 cases) > type 2 (26%, 52 cases) > type 1 (24%, 48 cases) > type 3 (23.5%, 47 cases). Conclusions The sulcal length did not vary in children, whereas the sulcal angle decreased with an irregular pattern. The sulcal angle decreased after prepubescent period, possibly due to the sphenoid sinus pneumatization and spheno-occipital synchondrosis. The sulcal length angle mostly in infants and young children may cause surgical orientation difficult during the resection of tumors using transcranial approaches.

Objective The main aim of this study placed on cadavers was to compare the data related to geniculate ganglion (GG) dehiscence and dimension obtained from computed tomography (CT) with dissection values. Methods This study was conducted on 20 temporal bones obtained from 10 cadavers (4 female, 6 male) aged between 45 and 92 (71.50 ± 15.98) years. All the measurements related to GG dimension were performed with a CT scanner and microdissection. Results The size of GG including its area, length, and width did not show statistically significant differences in terms of sex, side, and assessment method (CT and cadaveric dissections). The dehiscent GG was observed in 6 (30%) and 5 (25%) out of 20 temporal bones in CT and cadaveric dissections, respectively. The presence and absence of GG dehiscence in CT and dissection were similar in 75%. Conclusions Our findings based on dissection data suggest that radiologic evaluation of dehiscent GG detection might be erroneous by 25%, which highlights that surgeons should be careful when lifting the dura to prevent GG injury during middle cranial fossa surgical approaches. On the other hand, there was no statistical difference between CT and dissection measurements related to GG dimension.