The Geometrical Modeling of Aortic Root Complex.

BACKGROUND: This study was designed to investigate the anatomical relationship of the different levels of aortic root. MATERIALS AND METHODS: The morphological features of the aortic root were examined using of 12 adult hearts from fixed male cadavers who had expired due to noncardiac causes by magnetic resonance imaging and applied mathematical analyses to the results. The measurements of the aortic root were done at four levels: at the ventriculoarterial junction (annulus), at the largest level of the Valsalva sinuses (sinus), at the level of commissures (sinotubular junction [STJ]), and at 1 cm above the STJ (aorta ascendens). We derived an equation that allows calculation of the appropriate diameter of the aortic root from four levels. Statistical analysis among the variation of the diameters at the four levels of aortic root was achieved using test one-way analysis of variance. RESULTS: The data showed a geometric pattern of the aortic root. The comparison of the values from four levels showed that the narrowest at the sinotubular junctional level and the widest at the sinus level. CONCLUSION: The analysis of our data shows that the aortic root has a consistent shape with varying size and that is a definable mathematical relationship between root diameter.

Inferior Phrenic Arteries and Their Branches, Their Anatomy and Possible Clinical Importance: An Experimental Cadaver Study.

BACKGROUND: Transcatheter arterial chemoembolization is a common treatment for patients with inoperable hepatocellular carcinoma. If the carcinoma is advanced or the main arterial supply, the hepatic artery, is occluded, extrahepatic collateral arteries may develop. Both, right and left inferior phrenic arteries (RIPA and LIPA) are the most frequent and important among these collaterals. However, the topographic anatomy of these arteries has not been described in detail in anatomy textbooks, atlases and most previous reports. AIMS: To investigate the anatomy and branching patterns of RIPA and LIPA on cadavers and compare our results with the literature. STUDY DESIGN: Descriptive study. METHODS: We bilaterally dissected 24 male and 2 female cadavers aged between 49 and 88 years for this study. RESULTS: The RIPA and LIPA originated as a common trunk in 5 cadavers. The RIPA originated from the abdominal aorta in 13 sides, the renal artery in 2 sides, the coeliac trunk in 1 side and the left gastric artery in 1 side. The LIPA originated from the abdominal aorta in 9 sides and the coeliac trunk in 6 sides. In 6 cadavers, the ascending and posterior branches of the LIPA had different sources of origin. CONCLUSION: As both the RIPA and LIPA represent the half of all extrahepatic arterial collaterals to hepatocellular carcinomas, their anatomy gains importance not only for anatomists but interventional radiologists as well.

Classification and localization of the adductor hiatus: a cadaver study.

OBJECTIVE: To determine not only the vertical but also horizontal localization of the adductor hiatus (AH) and classify its shape and structure macroscopically. MATERIAL AND METHODS: Forty lower extremities were dissected to expose the AH. Its shape and structure were macroscopically noted, and the AH was classified into four types. For determining the localization, measurements were made with digital calipers. RESULTS: Twenty-four oval fibrous types, 12 oval muscular types, 2 bridging fibrous types and 2 bridging muscular types of AH were determined. For the horizontal localization of AH, the apex of the AH was determined to be located medial to the vertical line between the midpoint of the interepicondylar distance and the line which was drawn transversely from the apex of the AH, in all of the cadavers. For the vertical one, the apex of the AH was located in the middle third of the femur length in 14 thighs, and in the remaining 26 ones, the apex of the AH was located in the distal third of the femur length. CONCLUSION: Adductor hiatus was classified according to its shape and structure for the first time. Moreover, the localization of the AH was practically defined, in order not to harm the popliteal artery and vein.

The mendosal suture.

PURPOSE: The knowledge regarding the mendosal suture is still on debate in the literature. Though reports of the closure of this childhood suture are variable, a few reports show the presence of the suture in the adults. This study was conducted to determine the occurrence and a better topographic location of the mendosal suture. METHODS: We used 129 dry skulls for this study. In the specimens, which were determined to have a mendosal suture, the morphometric traits of the mendosal suture and the angle between the mendosal suture line and lambdoidal suture line (α angle) were measured. RESULTS: We found mendosal suture on 18 specimens, 11 of them were bilateral and 7 were unilateral. The length of these sutures ranged from 10.4 to 23.8 mm on the right side and 10.8 to 31.6 mm on the left side, respectively. The angle between two suture lines ranged from 36 to 68° on the right side and 32 to 75° on the left side. CONCLUSIONS: We believe that, these data will be of use to clinicians in order to avoid any misinterpretation of the mendosal suture with cranial fractures.

Surface anatomy of the transverse sinus for the midline infratentorial supracerebellar approach.

AIM: Knowing the location of the transverse sinus in the midline supracerebellar infratentorial approach is important to prevent its inadvertent injury. The external landmarks of the occipital bone have been studied in this anatomic study in order to reveal their relationship with the transverse sinus. MATERIAL AND METHODS: Fifty-two dried skulls were used to study the relationship of the transverse sinus with various surface bone structures. The key bone surface structures identified in each specimen were the superior nuchal line, the inferior nuchal line, the inion, internal occipital protuberance, and the transverse sulcus. RESULTS: The distance from the inion to the inferior nuchal line in specimens ranged from 12.7 mm to 37.7 mm. The distance from the inferior nuchal line to the midline foramen magnum in the specimens ranged from 19 mm to 34.75 mm. The width of the proximal transverse sulcus ranged from 2.6 mm to 10.16 mm with an average of 6.43 mm on the right side and 3.4 mm to 10.6 mm with an average of 6.15 mm on the left. CONCLUSION: The first and most superior burr hole for midline supracerebellar infratentorial approach can be safely placed approximately 1 cm below the inferior nuchal line. A burr hole in this localization will avoid the transverse sinus.

Evaluation of the bony landmarks in transcondylar approach.

BACKGROUND: The aim of this study is to define the anatomic landmarks which are necessary for transcondylar approach and to determine the importance of these structures during surgical resection. METHODS: 56 dry skulls were included in this study. Landmarks were detected. Some distances and angles, which were determined before, were measured and the anatomical structures were observed. 21 parameters were examined and analysed in totally 56 dry skulls using 56 foramen magnum, 112 hypoglossal canal and 112 occipital condyles. The landmarks which were used were the anterior and posterior borders of the occipital condyle, the medial and lateral margin of the occipital condyle, basion, opisthion, hypoglossal canal and posterior condylar canal. The measurements were made separately for the right and left sides. RESULTS: The mean length of the occipital condyle was found as 23.1 mm. The distance between the intracranial edge of the hypoglossal canal and anterior margin of the occipital condyle was measured as 11.2 mm in both sides. The distance between the intracranial edge of the hypoglossal canal and posterior margin of the occipital condyle was measured as 12.5 mm at the right side and 12.6 mm at the left one. The mean length of the hypoglossal canal was measured as 10.5 mm at the right side and 10.6 mm at the left one. 14 hypoglossal canals were divided into two compartments by a septum. CONCLUSIONS: In transcondylar approach, the anatomical landmarks should be well known in order to make a safe occipital condyle resection. The distance between the intracranial edge of the hypoglossal canal and posterior margin of the occipital condyle is important for a safe occipital condyle resection, and it was found to be 12.55 +/-0.05 mm in our study. Approximately 12 mm occipital condyle resection can be made without giving damage to the neural tissue. This value is appropriate to the (1/2) of the occipital condyle.

Surface anatomy of the posterolateral cranium regarding the localization of the initial burr-hole for a retrosigmoid approach.

Knowing the location of the venous sinuses is essential for the localization of the initial burr-hole for a retrosigmoid approach, in order to avoid inadvertent entry into the venous sinuses and limitation of the size of the bony opening. In this anatomic study, external landmarks of the posterolateral cranium have been studied, in order to reveal the relationship with the venous sinuses. Eighty-four dried adult human skulls were studied and study of both sides yielded 168 sides. Morphometric measurements of the posterolateral cranium have been performed and relations of the external landmarks with the venous sinuses have been studied. The anatomic position of the asterion was variable. The superior nuchal line was roughly parallel and below the lower margin of the sulcus of transverse sinus in all specimens. The sigmoid sinus, between the superior and inferior bends, seemed to descend along an axis defined by the junction of the squamosal-parietomastoid suture and the mastoid tip, in a slightly oblique fashion. In conclusion, a burr-hole placed just below the superior nuchal line and posterior to the axis defined by the mastoid tip and the squamosal-parietomastoid suture junction is appropriate for both avoiding inadvertent entry into the sinus and limiting the size of the craniotomy.

A multipurpose landmark for skull-base surgery: Henle's spine.

OBJECTIVE: To determine whether Henle's spine could be used as a reliable and multipurpose landmark for the other important structures of the skull base. MATERIALS AND METHODS: Ninety-two specimens from 46 cadaveric adult dry skulls were studied. Two imaginary lines and a triangle were defined: a spinopterygoidal line extending from Henle's spine to the root of the medial pterygoid plate, a bispinal line extending from one Henle's spine to the contralateral one, and a parapetrosal triangle lying between the spinopterygoidal line, the bispinal line and the sagittal midline. The parapetrosal triangle encompasses nearly all the main structures of the skull base, including the petrosal internal carotid artery. RESULTS: Along the spinopterygoidal line the distance from Henle's spine to the spine of the sphenoid was found to be about 3 cm, to the foramen spinosum 3.5 cm, to the posterior and anterior margins of the foramen ovale 4 and 4.5 cm, to the root of the lateral pterygoid plate 5 cm, to the root of the medial pterygoid plate 5.5 cm, and to the vomer 6.5-7 cm. Along the bispinal line, the distance from Henle's spine to the stylomastoid foramen was found to be about 1.5 cm, to the lateral and medial margins of the jugular foramen 2.5 and 3.5 cm, to the external orifice of the hypoglossal canal 4 cm, and to the foramen magnum 5 cm. CONCLUSION: Henle's spine with its superficial and central position can be used to localize important anatomical structures during skull-base surgery.

Morphometric evaluation of subaxial cervical vertebrae for surgical application of transpedicular screw fixation.

STUDY DESIGN: A morphometric evaluation of pedicle projections in 29 cervical spinal columns (C3-C7) for three-dimensional surgical anatomy for safe surgery was proposed. OBJECTIVE: In this study, pedicles and intimate structures of the subaxial vertebrae from C3 to C7 were evaluated to provide some morphometric data for cervical transpedicular screw fixation. SUMMARY OF BACKGROUND DATA: Detailed knowledge of surgical anatomy and variation of the subaxial vertebrae is a must for safe and effective surgery of the region. Although there are several clinical studies of transpedicular fixation, few studies have been performed on cervical pedicle measurements and their projection. METHODS: In 29 dried bone cervical spinal columns (C3-C7), pedicle dimensions (pedicle height, width, length), measurements of lateral mass and pedicle length distance and pedicle axis length, investigation of distances of superior facet-midpedicle axis and inferior facet-midpedicle axis, and transverse and sagittal angles of the pedicles were performed in linear and angular measurements. RESULTS: The obtained data from the series revealed that the mean values were approximately ranging from 6.7 to 7.2 mm for pedicle height, 4.4 to 4.9 mm for pedicle width, 5.3 to 6.2 mm for pedicle length, 15.3 to 16.0 mm for lateral mass and pedicle length, 22.2 to 27.7 mm for pedicle axis length, 3.8 to 5.3 mm for superior facet-midpedicle axis distance, 9.9 to 12.0 mm for inferior facet-midpedicle axis distance, 42.3 degrees to 51.5 degrees for transverse angle, and 5.2 degrees to 14.1 degrees for sagittal angle. CONCLUSIONS: Linear measurements of pedicle dimensions and also axial angles from horizontal and vertical planes may provide some anatomic limitations for subaxial cervical transpedicular screw fixation, and also contribute to the safety of the surgical procedure. One should also rely on tomographic data and computer-assisted guidance systems.

Eyebrow transplantation.

The eyebrow has a powerful influence on the appearance of the orbital region. Because the person without eyebrows has an unnatural look, drawing everyone's attention, eyebrow restoration/reconstruction should be viewed as an esthetic surgery performed to improve the patient's appearance and self-esteem. Although hair-bearing pedicled flaps and free composite strip grafts have been the most widely used approaches in clinical practice formerly, follicular unit transplantation (FUT) has gained more and more importance nowadays in eyebrow restoration because of its more rewarding results. The process and results of FUT have been greatly improved thanks to advances in hair transplantation techniques, instrumentation, and practice. In this article, we discuss the restoration of 14 eyebrows in 8 patients (5 males and 3 females) using FUT. The procedure and the results also are discussed here under in light of literature.

Follicular unit transplantation: the option of beard construction in eunuchoid men.

BACKGROUND: Psychosocial problems are very common in eunuchoids and may be related to the impact of underlying disorders on the physical appearance which makes them unable to overcome the sense of inferiority of childhood. A beardless patient treated with follicular unit transplantation (FUT) is reported here. OBJECTIVE: Such patients desire to get rid of a boyish appearance and want to achieve a masculine appearance. One of the easiest methods to achieve this goal is FUT. METHODS: By using an 18-gauge needle, the recipient bed was prepared under local anesthesia after premedication, and 1200 one- or two-hair micrografts were transplanted to the perioral (goatee) and its extensions to the sideburns. RESULTS: After completion of the procedure to the planned area, we achieved restoration of a masculine appearance which made the patient seem quite satisfied. CONCLUSION: The process of beard reconstruction is time consuming and tedious, but highly effective.