An incidence study on thyroglossal duct cysts in adults.

OBJECTIVE: To investigate the incidence of the asymptomatic thyroglossal duct anomalies and to review the literature and make comments on the significance of this condition. METHODS: A total of 80 cadavers were dissected in the present study. This study was carried out during 2005, where the cadavers were randomly included from the criminal laboratories of the Ministry of Justice, Republic of Turkey in Istanbul. None of the cadavers had laryngeal and cervical injuries resulting from a trauma or the cause of their death. The examined cadavers included 59 men and 21 females, and their age were ranged from 35-80 years old. The larynges were removed and fixed in 10% formalin and then dissected. The sections were examined using surgical SMZ 10 Nikon stereomicroscope. We evaluated the presence, localization, and diameter of the cysts with regard to age and sex of the cadavers. RESULTS: We observed a total of 12 different localization of thyroglossal ducts and cysts among the dissected 80 cadavers. Ten of these ducts cysts were found in males with an age range of 35-68 years and 2 in female cadavers aged 46-65 years. In 6 cases, the thyroglossal ducts and cysts were located in the left of the midline of the neck, while 3 cases were from the right of the midline, and the remaining was located on the midline of the neck. In all cases, thyroglossal ducts and cysts were complete and restricted to the infrahyoid region; all of them had connection with the hyoid bone, but not with the perichondrium of the cartilage. In addition, the thyroglossal ducts had connection with the left lobe of the thyroid glands in 3 cases, one case in the right lobe, and 2 cases with the isthmus of the thyroid gland. Finally, in 5 cases thyroglossal ducts were complete and had well-developed cysts. CONCLUSION: Thyroglossal duct remnants are one of the most often seen congenital asymptomatic masses of the neck region (7%). The presence of these duct remnants may lead to abnormal phonation and epithelial carcinomas. Therefore, correlation of the rate of thyroglossal duct remnants in a population together with the related clinical symptoms can lead to an early diagnosis and better treatment chances for these problems.

A scanning electron microscopic study of nasal respiratory epithelium in pregnant rats.

Pregnancy is a very important period in mammals. Various morphological and functional changes can be observed. Some studies examining nasal epithelial structure deal with changes found in pregnancy. In this study, a total of 16 adult female Sprague Dawley rats (8 control and 8 pregnant) were used. They were anesthetized with ketamine and sacrificed via cardiac perfusion with 2.5%-glutaraldehyde solution (in 0.1 M sodium phosphate buffer, pH 7.4). The heads of the rats were bisected midsagittally and one half was completely passed through the routine histological procedures for SEM examination. On the apical surfaces of ciliated cells of pregnant rat respiratory epithelium disoriented cilia and cilia with dilated blebs at their free ends were observed. In addition, some masses of mucus due to hypersecretion were striking. Goblet cells appeared swollen and their apical surfaces showed microvilli varying considerably in length and number.

Clinical implication of vascular and dimensional aspects of the cricothyroid space in the Turkish population.

OBJECTIVE: Cricothyroid space (CS) is one of the thinnest part in the framework of the larynx. The close relations of CS to the intralaryngeal subglottic area increase its anatomical importance. The aim of this study was to establish topographic distribution and the number of perforating vessels lying towards the intralaryngeal subglottic region and finding the calibrations of these vessels, thus revealing an index for the Turkish population. METHODS: In this study, 5 women and 45 men autopsy materials that had no pathology or previous surgery in the area were examined during the period February to November 2003. All specimens in this study were selected randomly from the criminal lab of the Republic of Turkey Ministry of Justice, Istanbul, Turkey. Microdissections were made by SMZ 10 Stereomicroscope. Superficial vascular structures of the membrane cricothyroidea at CS and their crossing places (foramens) to the intralaryngeal area, their numbers and localizations in relation to the midline (right/left and cranial/caudal) and their diameters were established. RESULTS: In the larynx dissections, which were made in 50 cases, a total of 180 vessels were seen. Seventy-eight vessels were situated on the middle line (cranial and caudal). Fifty-three vessels were at right side (cranial and caudal) and 49 vessels were at left side (cranial and caudal). In 20 specimens 2-4 vessels arrangement were passing through the foramen to the intralaryngeal subglottic area. Among these foramens, 20 of them consisted of 2 vessels (16 cranial, 4 caudal), 4 of 3 vessels (3 cranial, 1 caudal) and only one foramen was consist of 4 vessels (cranial). CONCLUSION: The cricothyroid area is an anatomical compartment enclosed by a connective tissue membrane and connected to the adjacent laryngeal region by vessels. This region is important with regard to surgical procedures, spread of laryngeal cancer and traumatic lesions of the larynx. Therefore, the clinical and surgical importance of vascular anatomy and the dimension of the cricothyroid space should be given emphasis in our population.

Scanning electron microscopic findings in respiratory nasal mucosa following cigarette smoke exposure in rats.

In the present study, the respiratory epithelium of the nasal mucosa of rats that had been exposed to cigarette smoke was examined by scanning electron microscope (SEM). Some significant morphological changes such as increased mucociliar activity, compound cilia, disorientation, short cilia and protrusive Goblet cells were observed.