Characterization of the mechanical properties of human parietal bones preserved in modified larssen solution, formalin and as fresh frozen.

PURPOSE: Although the fresh frozen (FF) cadaver is preferred for surgical applications, it is limited due to short usage time, unsuitable for reuse and the risk of infection. Due to its limited use, FF cadavers, which are covered by import in countries with insufficient body donation cause low-cost effectiveness. With the increase of real human tissue specimen necessities for surgical training, long-term preservation of the cadavers is crucial due to changes in mechanical properties. Therefore, studies on embalming solutions have increased in recent years. METHODS: We quantify the biomechanical properties of human parietal bones preserved via modified larssen solution (MLS) and compare the results with the specimens preserved as FF and fixed with 10% formalin-based solution (F10). The rectangular samples of 24 parietal bones of male individuals were resected from MLS-embalmed, F10-embalmed and FF cadavers to form three groups each containing eight samples. These specimens were tested longitudinally to identify mechanical properties. RESULTS: The tensile test results showed that there is not a significant difference between the groups in terms of stiffness, elastic modulus, strain at ultimate stress, failure strain and effective plastic strain. However, the yield stress, ultimate stress, yield strain, failure stress and total energy and post-yield properties are significantly lower in F10 than MLS and FF groups. CONCLUSION: It is observed that the mechanical properties of MLS preserved and FF parietal bones have almost similar properties. Thus, it can be concluded that MLS is a suitable fixative solution for bone studies and bone-related surgical anatomy training applications.

Morphometric assessment of important landmarks on skull intended for Vidian nerve surgery.

PURPOSE: The aim of our study was to determine guide parameters for clinicians by morphometric assessment of important landmarks on cranium intended for Vidian nerve surgery. METHODS: For the study, 23 half-skull bases, 40 skull bases and 40 skulls were obtained from the Department of Anatomy, Ege University Medicine Faculty. The vertical distances were measured using a digital caliper to the nearest 0.01 mm. RESULTS: The anterior opening of the Vidian canal (pterygoid canal) was observed as oval shaped on 57 specimens (31.1%), funnel shaped on 58 specimens (31.7%), round shaped on 64 specimens (35%) and septated on 4 specimens (2.2%). Vidian canal was embedded into the body of sphenoid on 55 specimens (52.4%) (embedded type) and protruded to sphenoidal sinus on 50 specimens (47.6%) (protruded type). 21 specimens of 50 were partial and 29 specimens were total. There were dehiscences on 21 specimens of 50 protruded type on the base of sphenoidal sinus (20%). Anterior opening of the Vidian canal was assessed according to medial lamina of pterygoid process. It was located medially in 169 of the specimens (92.3%) and laterally in 14 specimens (7.7%). CONCLUSION: Vidian canal and Vidian nerve are deeply located structures on skull. Vidian canal and surrounding structures are important landmarks for microsurgery and endoscopic approaches to Vidian nerve. We consider that knowledge of anatomical features of Vidian canal and preoperative imaging by CT (computed tomography) will be supportive when choosing and planning a safe surgical approach.

A surgical and anatomo-histological study on Transoral Endoscopic Thyroidectomy Vestibular Approach (TOETVA).

BACKGROUND: The number of TOETVA surgeries has increased worldwide but the anatomical passage of trocars is not clearly defined. We aimed to define detailed surgical anatomical passage of the trocars in cadavers. The incisions in oral vestibule, anatomical pathways of trocars, affected mimetic muscles, neurovascular relations of trocars and histological correlation of surgical anatomy were investigated. METHODS: Four cadavers and 6 six patient oral vestibules were used. The locations of optimised vestibular incisions were measured photogrammetrically. Initial steps of TOETVA surgery were performed on cadavers according to those optimal incisions. TOETVA preformed cadavers dissected to determine anatomical passages of the trocars. Afterwards, flap of lower lip and chin were zoned by software appropriate to the trocars routes. Histological analyses of the zones were made in correlation with dissections. RESULTS: Mimetic muscles associated with median (MT) and lateral trocars (LT) are orbicularis oris, mentalis, depressor anguli oris, depressor labii inferioris and platysma muscles. Trocars affect mimetic muscles in the perioral, chin and submental regions in different ways. The risk of mental nerve injury by MT is low. LT pass through the DLI muscle. The transmission of LT to the subplatysmal plane in the submental regions can be in two different ways. The arterial injury risk is higher with LT than the MT. CONCLUSIONS: The surgical anatomy of the perioral, chin and submental regions for the initial TOETVA steps has been defined. Detailed surgical anatomical passages of the MT and LT were determined. Anatomical pattern to reach subplatysmal plane are presented. Mimetic muscles effected by trocars were determined. Endocrine surgeons should know the anatomical passage of TOETVA trocars.

Changes in tissue gadolinium biodistribution measured in an animal model exposed to four chelating agents.

PURPOSE: This study investigated the potential to reduce gadolinium levels in rodents after repetitive IV Gadodiamide administration using several chelating agents. MATERIALS AND METHODS: The following six groups of rats were studied. Group 1: Control; Group 2: Gadodiamide only; Group 3: Meso-2,3-Dimercaptosuccinic acid (DMSA) + Gadodiamide; Group 4: N-Acetyl-L-cysteine (NAC) + Gadodiamide; Group 5: Coriandrum sativum extract + Gadodiamide; and Group 6: Deferoxamine + Gadodiamide. Brain, kidney, and blood samples were evaluated via inductively coupled plasma mass spectrometry. The brain was also evaluated histologically. RESULTS: Kidney gadolinium levels in Groups 4 and 5 were approximately double that of Group 2 (p = 0.033 for each). There was almost no calcification in rat hippocampus for Group 4 rodents when compared with Groups 2, 3, 5 and 6. CONCLUSION: Our preliminary study shows that excretion to the kidney has a higher propensity in NAC and Coriandrum sativum groups. It may be possible to change the distribution of gadolinium by administrating several agents. NAC may lower Gadodiamide-induced mineralization in rat hippocampus.

A large-scale outbreak of bovine ephemeral fever in Turkey, 2012.

Regional cases of bovine ephemeral fever (BEF) were documented previously in Turkey. Previous cases were confirmed in South-East Turkey with low cow mortality. Recent BEF-suspected outbreaks with high mortality were documented in many regions of Turkey in 2012. The aim of study was the epidemiological examination of the outbreak and molecular characterization of the viruses detected from the outbreak. For this reason, blood samples were collected from BEF-suspected outbreak regions. From the results of RT-PCR, high rate of BEF-suspected samples (48/60 or 80%) was found positive for BEF virus (BEFV) RNA. The nucleotide sequences of the G1 region of G gene of BEFV in the current study during the 2012 outbreak were grouped into cluster II of BEFV. It was suggested that BEFV may be spread out to other neighbor countries in the future years.