Omer Ozdogmus

Connections between the facial, vestibular and cochlear nerve bundles within the internal auditory canal

The vestibular, cochlear and facial nerves have a common course in the internal auditory canal (IAC). In this study we investigated the average number of nerve fibres, the average cross‐sectional areas of the nerves and nerve fibres, and the apparent connections between the facial, cochlear and vestibular nerve bundles within the IAC, using light and scanning electron microscopy. The anatomical localization of the nerves within the IAC was not straightforward. The general course showed that the nerves rotated anticlockwise in the right ear from the inner ear end towards the brainstem end and vice versa for the left ear. The average number of fibres forming vestibular, cochlear, and facial nerves was not constant during their courses within the IAC. The superior and the inferior vestibular nerves showed an increase in the number of nerve fibres from the inner ear end towards the brainstem end of the IAC, whereas the facial and the cochlear nerves showed a reduction in the number of fibres. This suggests that some of the superior and inferior vestibular nerve bundles may receive fibres from the facial and/or cochlear nerves. Scanning electron microscopic evaluations showed superior vestibular–facial and inferior vestibular–cochlear connections within the IAC, but no facial–cochlear connections were observed. Connections between the nerves of the IAC can explain the unexpected vestibular disturbances in facial paralysis or persistence of tinnitus after cochlear neurectomy in intractable tinnitus cases. The present study offers morphometric and scanning electron microscopic data on the fibre connections of the nerves of the IAC.

Trifurcation of the left common carotid artery: a case report.

During dissection of the carotid triangle, a carotid trifurcation was encountered. The left common carotid artery gave off three terminal branches: external carotid, internal carotid, and occipital arteries. The level of trifurcation was 35 mm above the superior margin of the thyroid cartilage. Further, the superior thyroid artery arose from the common carotid artery instead of the external carotid. Herein, we describe the detailed anatomical features of the variant branching pattern of the left common carotid artery and its clinical implications. Clin. Anat. 14:58–61, 2001.

The high 2D:4D finger length ratio effects on atherosclerotic plaque development.

BACKGROUND The index finger to ring finger length ratio (2D:4D) of the right hand are affected by prenatal testosterone levels in male. To date, it has been determined that the high 2D:4D ratio is related to the myocardial infarction, however no research has revealed the relationship between the high 2D:4D ratio whose coronary artery shows atherosclerotic plaque development. OBJECTIVE The aim of this study was to display the relationship between the 2D:4D ratio and atherosclerosis formation in male autopsy cases. METHODS We designed a study in 100 heterosexual male autopsies whose mean age was 21.4+/-2.47 (range between 17 and 25). The 2nd and 4th digits were measured on the palmar surface of the right hand and taken the right coronary artery to show the atherosclerotic plaque development. RESULTS AND CONCLUSION Grade 3 group had significantly higher 2D:4D ratio compared to Grade 1 and Grade 2 groups (p=0.02 for both).

A Reminder of the Anatomy of the Recurrent Artery of Heubner

Previous accounts of the recurrent artery of Heubner show serious inconsistencies concerning the origins, dimensions and numbers of the artery. In the present study, based on 54 (38 male, 16 female) human autopsy brains the common type of the recurrent artery of Heubner was present bilaterally in 46 cases (85.2%), while in 6 (11.1%) cases it was present only on one side (4 on the right, 2 on the left). Unilateral vessels were seen only in the male autopsy brains. The recurrent artery of Heubner could not be identified in 2 brains (3.7%). Multiple Heubner arteries were not observed in the present study. No gender differences were observed regarding the origin and dimensions of the recurrent artery of Heubner. 76 recurrent arteries of Heubner arising from the junction of the anterior cerebral artery (ACA) and anterior communicating artery (ACoA) (79.2%) had a mean diameter of 0.66+/-0.11 mm. In 14 arteries the artery derived from the A2 segment of the ACA (14.6%) and the mean diameter was 0.66+/-0.17 mm; in 6 arteries it originated from the A1 segment of the ACA (6.2%) and the mean diameter was 0.47+/-0.15 mm. The average diameter was calculated as 0.67+/-0.12 mm and ranged between 0.40 and 0.90 mm, irrespective of sex or side. A detailed anatomical knowledge of the recurrent artery of Heubner is important when considering vascular surgery in this area.

Changing Diameters of Cerebral Vessels with Age in Human Autopsy Specimens: Possible Relationships to Atherosclerotic Changes

AIMS/OBJECTIVES It has been previously recognized that the anatomy of arterial bifurcations influences blood flow and has a significant role in the development of vascular disease. MATERIAL AND METHODS In the present study, we measured the average diameters of the internal carotid (ICA), anterior cerebral (ACA), and middle cerebral arteries (MCA) in autopsy cases. We also calculated the outflow to inflow area ratios for four distinct age groups and for each gender, using 33 adult autopsies and 7 fetuses. RESULTS The area ratios decreased with age in both male and female samples. The decrease in the male (30%, p<0.05) was greater than the decrease for the female (17%, p > 0.05). The average diameter of the ACA, MCA and ICA of both female and male cases increased up to the 25-44 age group, decreased for the 45-64 age group, with a second increase above the age of 65. CONCLUSIONS The decrease in the area ratios and the pattern of changes of the dimensions of the cerebral vessels with age are useful to examine the causal relationships of these pathologic conditions and raises novel questions about age and gender differences in the structure of the intracranial vessels.

An Earplug Technique to Reduce the Gag Reflex during Dental Procedures

Background: The gag reflex is a frequent problem occurring during dental treatment procedures, especially while making impressions of the maxillary teeth. The present study aims to evaluate the efficacy of a simple earplug as an external auditory canal stimulator to supress the profound gag reflex and as a second step, to map areas of the oropharynx suppressed by this technique. Methods: In the first step of the study, 90 patients who had a gag reflex during the impression procedure were allocated to a study group, a sham group, and a control group for evaluating the efficacy of the earplug technique. Second, 20 new patients with a gag reflex were included in order to map the oropharnygeal areas suppressed by this technique. Results: The severity of the gag reflex was reduced in the earplug group (but not in the sham or the control group). The affected area included the hard palate, uvula, and the tongue but not the posterior wall of oropharynx. Conclusion: An earplug technique can be a useful, practical, and effective tool to overcome the gag reflex during oral procedures, such as impression procedures of maxillary teeth.