Neslihan Boyan

Morphometry of the hypoglossal canal, occipital condyle, and foramen magnum

The present study was undertaken to determine the detailed morphometry of occipital condyle (OC), hypoglossal canal (HC), and foramen magnum (FM) in Turkish–Caucasian skulls: measurements were taken from 59 dry skulls of unknown sex. There was no significant difference (P>0.05) in measurements taken from the right and left sides, consequently the overall means and associated standard deviations were calculated. The length of the HC was 9.9±1.9 mm and the HC intracranial and extracranial diameters were 6.5±1.3 mm and 6.6±1.1 mm, respectively, with the angle of the HC to the sagittal plane being 45.6±4.6 degrees. The distances from the intracranial and extracranial ends of HC to the jugular foramen were 13.3±3.3 mm and 8.4±2.0 mm, respectively, whereas the distances from the HC to the jugular tubercle, opisthion and basion were 12.2±2.2 mm, 29.2±2.6 mm, and 16.5±1.8 mm, respectively. The distances from the intracranial end of the HC to the posterior, anterior, inferior margins of the OC were 12.3±2.4 mm, 11.2±1.6 mm, and 9.4±1.2 mm, respectively. The anteroposterior length and transverse width of the OC were 24.5±2.5 mm and 13.1±1.6 mm, and the angle of the OC to the sagittal plane 31.5±5.1 degrees; the mean sagittal intercondylar angle was 62.2 degrees. The anterior and posterior intercondylar distances were 22.6±3.9 mm and 44.2±3.2 mm. The anteroposterior and transverse diameters of the FM were 34.8±2.2 mm and 29.6±2.4 mm, giving a mean FM index of 1.2. The presence or absence of a septum in the HC, protrusion of OC into the FM and the presence of condylar foramen were also determined. Detailed morphometric analysis will help in the planning of surgical intervention involving the skull base safer and easier.

Evaluation of Face Shape in Turkish Individuals

The aim of this study was to determine the types of face shape in the Turkish population. Knowledge on face shape is important in anthropology and for planning medical procedures such as in aesthetic, maxillofacial and orthodontic surgery. T he stud group consisted of 1003 healthy subjects (470 male, 533 female) aged 18–68 years. Mean height, weight and body mass index (BMI) were 1.74 m, 78.65 Kg, 25.80 ±3.50 kg/m and 1.62 m, 60.55 kg, 22.87 ±3.49 kg/m in males and females, respectively. Face length (FL; the distance from nasion to gnathion) and face width (FW; bizygomatic breadth) were measured, from which a Prosopic Index (PI) was determined using the following formula: (PI= FL/FW x 100). The types of face shape were classified according to Banister’s clas sification Type I (hypereuryprosopic), Type II (euryprosopic), Type III (mesoprosopic), Type IV (leptoprosopic), Type V (hyperleptoprosopi c) in both males and females. PI was 84.31 (FL: 12.07 cm; FW: 14.34 cm) in males and 85.25 (FL: 11.30 cm; FW: 13.28 cm) in females. I males and females Type I face shape was observed in 18.1 % and 15.6 %; Type II in 35.3 % and 34.3 %; Type III in 33.2 % and 34. 3 ; Type IV in 8.7 % and 11.8 %; and Type V in 4.7 % and 3.9 %, respectively. The determination of types of face shape as presented in thi study may be useful for aesthetic surgical procedures as well as medical and anthropological investigations.

Clinical significance and morphometric analysis of the periorbital foramina

The location of the frontal (FF), supraorbital (SOF), and infraorbital (IOF) foramina relative to frequently encountered anatomic landmarks in (Turkish) dry skulls were determined, with measurements taken from both sides of 45 dry skulls. The width and lengths of the left and right FF were 2.8 and 3.1 mm, and 1.9 and 2.2 mm, respectively: the widths and lengths of the SOF and IOF were 2.9 and 2.1 mm, and 3.7 and 3.9 mm. The distances from the center of the FF and SOF to the nasal midline were 19.3 mm and 25.8 mm; from the FF to the angulus oculi medialis 7.6 mm on the left and 6.4 mm on the right; from the SOF to the angulus oculi medialis 12.6 mm: from the center of FF to the center of the SOF 9.2 mm; from the center of the SOF to the temporal crest of the frontal bone 26.1 mm; from the center of the IOF to the nasal midline, maxillary midline, infraorbital margin, and zygomaticomaxillar suture 46.8, 27.2, 7.3, 10.2 mm respectively; between the superior walls of the infraorbital and supraorbital foramina 45.4 mm. The IOF was classified as oval, round, or semilunar, whereas the location of the FF, SOF, and IOF were graded I of VI in relation to the roots of the maxillary teeth. Accessory SOF and IOF were observed on both the left and right sides. The angle subtended by a line through the anterior nasal spine and IOF and the horizontal plane (AIOF) was 30.5 degrees on the left and 32.5 degrees on the right. A new parameter, the naso-orbital angle, was 72.1 degrees on the left and 70 degrees on the right and can be used to locate the relative positions of the SOF and IOF. The data presented here will help in the planning of surgical procedures and the application of local anesthetics.

Anatomy and Clinical Importance of the Extracranial Clivus and Surrounding Structures

The aim of this study was to reveal the clinical importance of measurements taken from the pharyngeal tubercle (PT) to various anatomical structures around the extracranial clivus. Twenty-six adult dry Anatolian skulls were examined. The extracranial clivus and PT were used as landmarks from which various distances were measured using a digital caliper accurate to 0.01 mm. Th e following mean distances from the PT were observed; foramen lacerum (FL) (L: 17.15 mm, R: 17.4 mm) ; medial external margin of the carotid canal (CC) (L: 26.7 mm, R: 27.5 mm); anterior tip of occipital condyle (OC) (L: 16.4 mm, R: 16.3 mm); anterior margin o f foramen magnum (FM) (10.8 mm); foramen ovale (FO) (L: 25.9 mm, R: 29.1); medial margin of the jugular fossa (JF) (L: 25.4 mm, R : 25.7 mm); medial external margin of the hypoglossal canal (HC) (L: 20.0 mm, R: 19.9 mm). Mean bilateral distances were: LFO-RFO : 45.34 mm; LFL-RFL: 20.1 mm; LCC-RCC: 52.1 mm; LOC-ROC: 17.6 mm; LJF-RJF: 45.2 mm; LHC-RHC: 33.5 mm. The following mean distances were observed from the FM: FM-OC (L: 8.3 mm, R: 9.3 mm); FM-HC (L: 17.8 mm, R: 17.4 mm). Also the mean distance of OC-HC were observed (L: 11.7 mm, R: 11.4 mm). Present measurements suggest that the PT can be used as an anatomical landmark during surgery involving clival pathology. However, the anatomy and variations of the extracranial clivus and surround ing structures must be taken into consideration.

Surgical importance of the morphometry of the anterior and middle cranial fossae

The present study was undertaken to determine the morphometric relationships between specific aspects of the cranial anterior and middle fossae because of their importance as landmarks in surgical approaches to the skull base. Bilateral and midline measurements were made between specific anatomic landmarks. The mean midline anteroposterior width of the lesser wing of the sphenoid and distance from the crista galli to the tuberculum sellae were 20 and 35.6 mm, respectively. Significant differences (P<0.05) between right and left sides measurements were observed for the length of the lesser wing of the sphenoid (46.6 mm right, 44.8 mm left), the distance between the crista galli and the lateral tip of the sphenoid (53.1 mm right, 51.1 mm left), and the angle subtended by the distance between the tuberculum sellae and the internal acoustic meatus (57.3 degrees right, 55.1 degrees left). No other differences in bilateral measurements were observed. The mean length of the lateral tip was 2.6 mm; the mean distance between the crista galli and the midpoint of the lesser wing was 31.5 mm; the mean distances between the foramen ovale and the anterior clinoid process and the midpoint of the lesser wing were 23.0 and 32.1 mm, respectively. The mean distances between the internal acoustic meatus and the lateral tip and the tuberculum sellae were 55.9 and 49.5 mm, respectively. The mean angle between the midline and the lateral tip measured at the crista galli was 59.10 degree. The mean angle subtended by the distance from the crista galli to the tuberculum sellae at the lateral tip was 43.30 degree. A sound knowledge and understanding of the relationships between morphometric measurements and the relevant anatomic structures in relation to the sphenoid may be of use to neurosurgeons.