Topographic anatomy of the endolymphatic sac: a pilot cadaveric dissection study.

PURPOSE: The precise location of the endolymphatic sac (ES) may be difficult during surgical approaches. This morphometric study aimed to determine the exact location of ES in adult human cadavers for the management of pathologies such as Meniere's disease. METHODS: Twenty temporal bones of 10 adult cadavers (mean age: 70 ± 13.40 years, range: 45-92 years; sex: 4 males and 6 females) fixed with 10% formalin were bilaterally dissected to obtain numeric data about the location of ES. RESULTS: Distances of ES to the posterior semicircular canal (PSC), Donaldson line (DL), sigmoid sinus (SS) and sinodural angle (SA) were found as 2.76 ± 1.18 (0.96-5.58) mm, 1.74 ± 1.13 (0.58-5.07) mm, 2.30 ± 1.09 (0.54-4.91) mm and 16.04 ± 3.15 (9.82-22.18) mm, respectively. In addition, the angle between the tangents passing through the cortical bone (CB) and SS was determined as 35.37°±11.32° (21.30°-60.58°). No statistical difference was found between right-left or male-female measurements (p > 0.05). CONCLUSION: DL, SS, and PSC are essential anatomical landmarks for determining the location of ES. The spatial location of SS, including its depth to the cortical bone and the distance to anteriorly located anatomical structures of the mastoid cavity consisting of the facial nerve and PSC, is believed to be underlined for ES surgery. Our data may be used as a database to further define the relationship between ES and adjacent anatomical structures (SS, PSC, etc.) during the application of surgical approaches.

Precise localization of parotid duct: a cadaveric study.

This study aimed to determine the precise localization and course of parotid duct based on morphometric data obtained by measurements regarding several superficial landmarks and lines. Totally, 46 parotid ducts of 24 formalin-fixed adult amputated heads (12 female and 12 male) aged between 45 and 92 years, present in the collection of Anatomy Department, School of Medicine, Mersin University, were evaluated. First, three reference lines were defined: L1: between intertragic notch and labial commissure, L2: between intertragic notch and nasal wing, and L3: between intertragic notch and lateral palpebral commissure. The location of the parotid duct with respect to these lines were recorded. In all sides, parotid duct was detected in the middle 1/3 of L1. In 71.7% of all hemifaces, the parotid duct was making an upward curve around L1. Its proximal end exiting from the anterior border of the parotid gland was 12.34 ± 28.83 mm below the proximal 1/3 point of L1. Then, it was crossing L1 at a point with a mean distance of 53.90 ± 9.69 mm from the labial commissure where it is almost at L1 midpoint. Its distal end was located 9.61 ± 2.88 mm above the distal 1/3 point of L1. In 21.7% of all hemifaces, PD was observed totally above L1, while the shortest distances of its proximal and distal ends to L1 were 4.35 ± 2.45 mm and 13.17 ± 4.52 mm, respectively. In 6.5% of all hemifaces, its proximal end was located just on L1, coursing upwards and terminating 11.76 ± 2.53 mm above L1.

The Comparison of the Right and Left Sigmoid Sinus Cross-Sectional Areas in Fetal Period and the Factors Affecting the Venous Dominance.

OBJECTIVES: Skull base is an important and a challenging area for surgeons. Success in skull base surgery depends on various factors such as pre-operative evaluation, appropriate surgical technique, anesthesia duration, intraoperative neuromonitorization and wound care. MATERIALS AND METHODS: This study was performed in the Anatomy dissection laboratory of M.U. Medical Faculty (Ethical committee approval number 2010-103). Twelve fetuses between 17-33 gestational weeks fixed with formaldehyde were enrolled to the study. RESULTS: This study was planned to investigate the cross sectional areas of the sigmoid sinus in three levels to compare the right-left sides and the probable relationship among the levels in fetuses to further delineate the developmental factors on jugular foramen asymmetry. The cross-sectional measurements of sigmoid sinus lumen were done on 3 levels which are described as A1 level; sinodural angle, A2 level; the midpoint between the sinodural angle and endocranial orifice and A3 level as the entrance (endo-cranial orifice) of the jugular foramen. There is a strong positive correlation between left (L) A1 and L A2 and also the same for L A1 and right (R) A2. These strong and positive correlations are all valid between L A2-L A3, L A2-R A2, L A2-R A3, L A3-R A3, R A1-R A2. CONCLUSION: Multicenter studies would be beneficial to investigate the topic with greater number of fetuses also on the different regions for genetic differences.

Quantitative and Neurovascular Anatomy of the Growing Gracilis Muscle in the Human Fetuses.

This study is intended to obtain the algebraic growth dynamics of the gracilis in fetuses and determine the variations of neurovascular pedicle(s) of the gracilis, to aid infant surgeries. Forty fetuses (19 males and 21 females) were included in the study. Gestational mean age of the fetuses was 22.40 ±â€Š2.67 (range, 18-28) weeks. Numerical values were obtained using a digital caliper and a digital image analysis software. Linear functions for the surface area, width, anterior, and posterior margin lengths of the gracilis were calculated, respectively, as: y = -289.307 + 20.501 × age (weeks), y = -7.113 + 0.622 × age (weeks), y = -24.421 + 3.434 × age (weeks), and y = -24.397 + 3.314 × age (weeks). In addition, length and width of the gracilis tendon were calculated as y = -6.676 + 0.934 × age (weeks) and y = -0.732 + 0.074 × age (weeks), respectively. Parameters of the gracilis had no statistically significant difference regarding side and sex (P > 0.05). In all the specimens, the gracilis was innervated by the anterior branch of the obturator nerve. Blood supply of the gracilis was identified to be derived from 1 single artery in 38 sides of total 80 (47.5%), from 2 arteries in 36 (45%) and from 3 arteries in 6 (7.5%). In 74 sides (92.5%), the nerve was superficial to the main artery, whereas in 6 sides (7.5%), it was deeper. The data of the present study could be beneficial for surgeons in infant surgeries to treat conditions such as obstetrical brachial plexus paralysis, facial palsy, or anal incontinence. Linear functions can be utilized to better evaluate the growth course of the gracilis in fetuses and to predict the dimensions thereof. Additionally, comprehending the structure and recognizing the variations of the gracilis nerves and arteries can help to protect the neurovascular pedicle(s) of the gracilis during the operations.

Anatomy of Master Knot of Henry: A morphometric study on cadavers.

OBJECTIVE: The objective of this study was to evaluate the features of flexor hallucis longus (FHL), flexor digitorum longus (FDL) and flexor digitorum accessorius (FDA) muscles with relevance to the tendon grafts and to reveal the location of Master Knot of Henry (MKH). METHODS: Twenty feet from ten formalin fixed cadavers were dissected, which were in the inventory of Anatomy Department of Medicine Faculty, Mersin University. The location of MKH was identified. Interconnections of FHL and FDL were categorized. According to incision techniques, lengths of FHL and FDL tendon grafts were measured. Attachment sites of FDA were assessed. RESULTS: MKH was 12.61 ± 1.11 cm proximal to first interphalangeal joint, 1.75 ± 0.39 cm below to navicular tuberosity and 5.93 ± 0.74 cm distal to medial malleolus. The connections of FHL and FDL were classified in 7 types. Tendon graft lengths of FDL according to medial and plantar approaches were 6.14 ± 0.60 cm and 9.37 ± 0.77 cm, respectively. Tendon graft lengths of FHL according to single, double and minimal invasive incision techniques were 5.75 ± 0.63 cm, 7.03 ± 0.86 cm and 20.22 ± 1.32 cm, respectively. FDA was found to be inserting to FHL slips in all cases and it inserted to various surfaces of FDL. CONCLUSION: The exact location of MKH and slips was determined. Two new connections not recorded in literature were found. It was observed that the main attachment site of FDA was the FHL slips. The surgical awareness of connections between the FHL, FDL and FDA, which participated in the formation of long flexor tendons of toes, could be important for reducing possible loss of function after tendon transfers postoperatively.

Morphometric properties of the latissimus dorsi muscle in human fetuses for flap surgery.

PURPOSE: Although latissimus dorsi (LD) flaps are extensively used in a wide range of interventions, fetus studies on this subject are quite limited. This study aims to obtain detailed information about the morphometric features of LD, thoracodorsal artery (TDA) and nerve (TDN). METHODS: The study was carried out on both sides of 50 formalin-fixed human fetuses (22 male/28 female) with a mean gestational age of 24.5 ± 4.7 (range 18-36) weeks, which were in the inventory of Anatomy Department of Mersin University Faculty of Medicine. Dimensions of LD, lengths and width of TDA and TDN were measured. Surface area of LD was calculated using digital image analysis software. RESULTS: All samples had LD muscle. Neither gender nor side-significant differences were observed in relation with the numerical data of LD, TDN and TDA. Linear function of surface area was calculated as "y = - 1767.532 + 114.582 × Age (weeks)". LD was attached directly to the posterior part of iliac crest in 59 of 100 sides meanwhile in the rest 41, it was attached by the thoracolumbar fascia. TDA gave a branch to serratus anterior in 96 cases and 2 branches in 4 cases. TDN passed superficial to TDA in 84 and deep to TDA in 16 samples. TDN had bifurcation in 93, trifurcation in 6 and tetrafurcation in 1 side. CONCLUSION: Data obtained from this study can be useful for estimating the sizes of LD and related neurovascular structures, especially in neonate surgeries. Linear function of LD surface area can be helpful to design the flap dimensions in newborn surgeries. A throughout knowledge about the branching pattern of TDN and its location-wise relation with TDA should be kept in mind to prevent possible complications during harvesting LD flaps and TDN grafts.

Measurements for the direct approach to the oval foramen to apply mandibular nerve blockade.

PURPOSE: The lack of certain quotable landmarks and not taking the morphometric variations into consideration for mandibular nerve blockade can cause some complications. The aim of this study was to ensure there are data for more feasible and successful lateral extraoral approach to block the mandibular nerve by proposing reliable and quotable landmarks. METHODS: The current study was carried out on 55 skulls at the anatomy departments of the Universities of Mersin and Ankara. The length of the zygomatic arch, measurements indicating the puncture point (PP), injection depth, and injection angle were revealed. The differences between sides and the relationships between the parameters were evaluated by using paired t-test and Pearson correlation test, respectively. RESULTS: Of all skulls, it is observed that the injection line passed anterior to the articular surface of the temporomandibular joint. The distance between external acoustic opening and PP showed positive correlation with the distance between oval foramen and the midpoint of the zygomatic arch on the left side (r = 0.364, P = 0.001). On the right, the correlation was close to the statistically significant level (r = 0.280, P = 0.072). The distance between external acoustic opening and PP that can be adapted to the living subjects was found as 26.31 ± 1.95 mm. Injection angle to the coronal plane was measured to be 16.39 ± 2.96 degrees. The difference between sides for this parameter was not statistically significant. CONCLUSIONS: The determined parameters are suggested to be convenient and quotable to help in successful direct application under three-dimensional computed tomography or computed tomography-fluoroscopy for blocking the mandibular nerve.

Effects of trapidil after crush injury in peripheral nerve.

In this study, we evaluated the effects of trapidil on crush injury by monitoring nitric oxide, malondialdehyde and transforming growth factor-Beta2 levels and by transmission electron microscopy in the rat sciatic nerve. The sciatic nerve was compressed for 20 sec by using a jewelers forceps. Trapidil treatment groups were administrated a single dose of trapidil (8 mg/kg) intraperitoneally just after the injury. The crush and crush + trapidil treatment groups were evaluated on the 2nd, 7th, 15th, 30th and 45th days of the post-crush period. On the 7th and 15th days, damage in thin and thick myelinated axons, endoneural edema and mitochondrial swelling were less severe in the trapidil group histopathologically. These findings supported the idea that trapidil prevented cell damage and edema at the injury site. Day/group interaction with regard to serum nitric oxide, malondialdehyde and transforming growth factor-Beta2 levels did not show significant changes.