Ismet Bayramoglu

Anatomy of the Guinea Pig Temporal Bone

The middle ear of guinea pigs has long been used for experimental studies, but no detailed information about its temporal bone anatomy is available. In 18 adult guinea pigs, the temporal bone, eustachian tube, and inner ear anatomy, in addition to the anatomy of the middle ear, were investigated under the dissection microscope. In addition to properties of the eardrum, ossicles, air cell system, and cochlea previously described, the appearance of Huschkes foramen and the crista stapedis in an adult guinea pig ear, the structure of the eustachian tube, the architecture of the internal auditory canal, and the communication of the mastoid cells with the tympanic bulla are described. Differences and similarities among guinea pigs, other experimental animals, and humans are discussed to show the advantages and disadvantages of the guinea pig ear for experimentation.

Practical Use of MESNA in Atelectatic Ears and Adhesive Otitis Media

Objective: MESNA is a synthetic sulfur compound that produces mucolysis by disrupting disulfide bonds. This study aimed to address indications and technique of MESNA application in otologic surgery, especially in retraction pockets and adhesive otitis media. Methods: MESNA application was performed in 42 ears of 39 patients. The diagnoses were retraction pockets fixed to incudostapedial joint, stapes or promontorium, and adhesive otitis media in 24 and 17 ears, respectively. Calculations were performed according to 24 ears of 23 patients with follow-up data. Results: One or more of the following surgical interventions were performed: MESNA application alone and ventilation tube insertion, reinforcement or mastoidectomy in addition to MESNA application. Sensorineural hearing loss was not encountered after MESNA application. The operation was successful in 79.2%. Overall revision surgery was needed in 20.8% of the ears. In 71.4% of the ears treated with MESNA alone, revision surgery was needed. Conclusion: In the light of our experience, we advocate the use of MESNA in atelectatic ears, because it makes the operation easy and safe by allowing elevation of the tympanic membrane by its mechanical and chemical actions.

Evaluation of the Results of Endoscope-Assisted Acoustic Neuroma Surgery through Posterior Fossa Approach

The objective of this study was to evaluate the results of endoscope-assisted acoustic neuroma surgery in posterior fossa approach. Between 1996 and 2002, 60 consecutive patients with acoustic neuroma were operated via the retrosigmoid suboccipital approach. Standard 4-mm sinus endoscopes at different angles were used during the surgeries either for inspection or tumor endoscopic dissection. Clinical parameters and treatment outcome were evaluated retrospectively. Tumor sizes were small, medium and large in 46.6, 45 and 8.3% of the patients, respectively. The hearing preservation rate, which did not correlate with tumor size (p > 0.05), was 24.4%. The need for facial reanimation surgery, which was needed in 5% of patients, was significantly higher in the large tumors than in the small and medium tumors (p < 0.001). Cerebrospinal fluid fistula rate, which was not related to tumor size (p > 0.05), was 13.3%. Tumor recurrence or residual tumor was not encountered at all. In conclusion, endoscopes give accurate information about the relationship between the tumor and the adjacent structures and help control the fundus of the internal auditory canal to ensure complete tumor removal. It is also helpful in visually verifying the continuity of the facial and cochlear nerves. The use of endoscopes does not appear to increase the hearing preservation rate, but is very helpful in complete tumor removal in the posterior fossa approach.

Ultrastructural analysis of the chorda tympani nerve in chronic suppurative otitis media.

Objective: To compare ultrastructure of the chorda tympani nerve by light and electron microscopy in patients with otosclerosis and chronic suppurative otitis media. Study Design: Comparative prospective study. Setting: Tertiary care, referral medical center. Patients: The tympanic segments of chorda tympani nerves were collected for ultrastructural investigation in 20 cases with chronic suppurative otitis media and 10 cases with otosclerosis that underwent middle ear surgery. Results: Histopathologic examinations of the suppurative group showed that unmyelinated fibers were almost totally lost and replaced by collagen fibers. The thickness of the myelin sheaths was very slender, whereas some of them were atrophic. A substantial increase was encountered in the endoneural collagen substance and connective tissue, whereas inflammatory elements and edema were present occasionally. Degenerative alterations of the myelinated fibers mainly occurred in the form of adaxonal vacuoles. There was disorganization and separation of parallel lamellae of Schmidt-Lanterman clefts. Conclusion: The chorda tympani nerve should be preserved in otologic surgery. However, inadvertent dissection of the chorda tympani nerve in chronic suppurative otitis media surgery will not possibly cause a postoperative disturbance in light of ultrastructural changes that occur in the nerve.

Surgical Treatment of Peripheral Vertigo and Vertiginous Diseases

Although our understanding of the mechanisms of vertigo and pathophysiology of vertiginous disorders has increased, diagnosis and treatment of various vertiginous diseases is challenging. The objective for the treatment of a vertiginous disease is to eliminate the underlying pathology either with maneuvers or drugs. In vertiginous diseases, surgery is performed either to eliminate the underlying pathologic event or to create stability in the incoming vestibular signals. It is not always possible to treat the underlying disease. Therefore, surgery is usually performed for the relief of vertigo. There are various surgical approaches used to treat a variety of vertiginous diseases. Selection of the approach depends on the type of vertiginous disease. This review mainly focuses on the current status and outcome of the surgeries used in the treatment of a variety of vertiginous diseases.

Expression of cyclooxygenase-2, 12-lipoxygenase, and inducible nitric oxide synthase in head and neck squamous cell carcinoma.

AimThe objective of this study was to investigate whether cyclooxygenase-2 (COX-2), 12-lipoxygenase (12-LOX), and inducible nitric oxide synthase (iNOS) have a role in carcinogenesis of head and neck squamous cell carcinoma (HNSCC). Materials and MethodsTwenty-two patients with HNSCC were included in the study. Cancer tissues and adjacent normal mucosa were obtained from each patient. Real-time PCR was used to assess the expression of COX-2, 12-LOX, and iNOS. ResultsCOX-2 and 12-LOX mRNA expressions are significantly increased in HNSCC compared with adjacent normal mucosa. Expression of iNOS was not significantly elevated in overall head and neck cancer tissues compared with normal mucosa. However, iNOS expression was found to be significantly elevated in patients with laryngeal cancer. ConclusionThese data suggest that COX-2 and 12-LOX may play a role in carcinogenesis of head and neck cancer. iNOS as well as COX-2 and 12-LOX may play a role in carcinogenesis of laryngeal cancer.

Combined retrosigmoid retrolabyrinthine vestibular nerve section: results of our experience over 10 years.

Objective: We aimed to evaluate the results of our experience in vestibular nerve sectioning (VN), which was performed using combined retrosigmoid-retrolabyrinthine approach. Study Design: Medical records of 280 patients who were consecutively operated on for incapacitating peripheral vertigo were retrospectively evaluated, and 210 patients who completed 2 years follow-up and had adequate follow-up data were found to be suitable for inclusion in the study. Methods: Hearing results, vertigo control rates, and complications of the retrosigmoid-retrolabyrinthine VN were evaluated. Results: The patients were suffering from vertigo for a mean period of 32.2 months. Bilateral Ménières disease occurred in 5.7% of the patients in the follow-up period. A complete or substantial vertigo control could be achieved in 94.4% of the patients (191 [90.1%] in Class A and 9 [4.3%] in Class B). Preoperative speech reception threshold, pure-tone average, and speech discrimination score of the patients were 56.5 dB, 47.4 dB, and 73.6%, respectively. Postoperative corresponding values were 62.2 dB, 43.4 dB, and 68.5%, respectively (p > 0.05). The complication rate was low (2.5%). Most common complication was abdominal hematoma, which was seen in 4.5%. Conclusion: VN performed using retrosigmoid-retrolabyrinthine approach has low complication and high vertigo control and hearing preservation rates. It can be applied as an initial surgery or reserved as the last step when the other surgical treatments have failed to control vertigo.

Combined retrosigmoid retrolabyrinthine vestibular nerve section: Results of our experience over 10 years. Otol Neurotol 2005;26:481-483

OBJECTIVE We aimed to evaluate the results of our experience in vestibular nerve sectioning (VN), which was performed using combined retrosigmoid-retrolabyrinthine approach. STUDY DESIGN Medical records of 280 patients who were consecutively operated on for incapacitating peripheral vertigo were retrospectively evaluated, and 210 patients who completed 2 years follow-up and had adequate follow-up data were found to be suitable for inclusion in the study. METHODS Hearing results, vertigo control rates, and complications of the retrosigmoid-retrolabyrinthine VN were evaluated. RESULTS The patients were suffering from vertigo for a mean period of 32.2 months. Bilateral Menieres disease occurred in 5.7% of the patients in the follow-up period. A complete or substantial vertigo control could be achieved in 94.4% of the patients (191 [90.1%] in Class A and 9 [4.3%] in Class B). Preoperative speech reception threshold, pure-tone average, and speech discrimination score of the patients were 56.5 dB, 47.4 dB, and 73.6%, respectively. Postoperative corresponding values were 62.2 dB, 43.4 dB, and 68.5%, respectively (p > 0.05). The complication rate was low (2.5%). Most common complication was abdominal hematoma, which was seen in 4.5%. CONCLUSION VN performed using retrosigmoid-retrolabyrinthine approach has low complication and high vertigo control and hearing preservation rates. It can be applied as an initial surgery or reserved as the last step when the other surgical treatments have failed to control vertigo.