Deletion mapping of chromosome 4q22-35 and identification of four frequently deleted regions in head and neck cancers.

Head and neck squamous cell carcinoma (HNSCC) is a diverse group of cancers that are frequently aggressive in their biologic behavior. Inactivation of tumor suppressor gene (TSG) is one of the most critical steps leading to HNSCC. Loss of heterozygosity analysis is very sensitive method for the detection of frequent allelic loss in a chromosomal locus. This method has been considered as an important evidence for the localization of TSGs. We analyzed loss of heterozygosity (LOH) at chromosome 4q22-35 region by using 14 polymorphic microsatellite markers in 83 matched normal and HNSCC tissues. LOH was detected at least in one location in 71 of 83 (86%) tumor tissues. Frequent deletions were detected at the location of microsatellite markers, D4S2909 (46%), D4S2623 (51%), D4S406 (48%), D4S1644 (45%) and D4S2979 (40%). Four different frequently deleted regions at 4q22, 4q25, 4q31 and 4q34-35 were observed. These regions include several putative TSGs such as Caspase-6, SMARCAD1, SMARCA5, SAP30 and ING2. Further molecular analysis of each gene should be performed to clarify their roles in head and neck squamous cell carcinogenesis.

Lack of B-RAF mutations in head and neck squamous cell carcinoma.

B-RAF is one of the most commonly mutated oncogenes in human cancer. However, the mutation status of B-RAF has not been established completely in HNSCC. We have analysed the mutation status of the kinase domain of the B-RAF gene (exons 11 and 15) in 91 Japanese HNSCC patients as well as 12 HNSCC cell lines. DNA was extracted and amplified by PCR. Mutations were then analysed by SSCP mutation detection method. Since V600EB-RAF constitutes 90 % of the mutations identified in B-RAF in human cancers, we also used MASA analysis to specifically detect this mutation in exon 15 of B-RAF. Using both methods, no mutation was found in both exon 11 and 15 in all patients and cell lines. Mu tations are absent or rare in the kinase domain of B-RAF in Japanese HNSCC. However, more studies are still needed to determine its usefulness as a target for molecular therapy in these patients.

A study on the prevalence of accessory auricle anomaly in Turkey.

OBJECTIVE: Accessory auricular anomaly is a small elevation of skin containing a bar of elastic cartilage localized most commonly just anterior to the tragus or ascending crus of the helix. The anomaly may exist isolated or may be associated with other congenital anomalies of the first arch. The purpose in this study is to detect prevalence of accessory auricle in Turkey and find out whether it is associated with other craniofacial anomalies or hearing loss. METHODS: The study was performed on 850 children from the age of 7 to 9 during a screening program in primary schools. Complete otolaryngologic examination and acoustic reflectometry measurements were performed on all the children. Full physical examination, tympanometric and audiometric evaluation and EEG measurements were added to the cases with accessory auricle anomaly. RESULTS: Among 850 children examined, four had accessory auricle anomaly and prevalence of the anomaly was calculated as 0.47% (95% confidence interval (CI), 0.13-1.20%). Children were developmentally normal, and no other congenital craniofacial or systemic anomaly was detected in any of the cases. Further, tympanometric, audiometric evaluations and EEG tests were in normal limits. CONCLUSIONS: In this study, the prevalence rate of the condition was calculated as 0.47%. Although one study from China reported this prevalence as 0.22%, the difference between the reported prevalances was not statistically significant. Further, although external ear anomalies may present together with cranifacial anomalies and neurologic disorders like epilepsy, neuromotor retardation and EEG disorders, in our cases, mental and motor development was normal and epilepsy history or abnormal EEG patterns do not exist. On the other hand, no hearing loss was found to be associated with accessory auricles.

Tympanometry and acoustic reflectometry in ears with chronic retraction without effusion.

OBJECTIVE: Purpose of this study was to find out test accuracy and predictivity of tympanometry (TYMP) and parameters (reflectivity and curve angle) of acoustic reflectometry (AR) in the ears with prior clinic and otoscopic evidences of effusion in which no effusion was detected by myringotomy, by comparing with the data found in normal ears and in those with effusion. METHODS: While study group included 31 ears with chronic retraction in which no effusion was detected by myringotomy, control group included 150 fully normal ears and 150 ears with effusion confirmed by myringotomy. B tracings in TYMP, and values of reflectivity higher than 5 and curve angle lower than 75 degrees in AR were accepted as indicators of effusion; in the combined test, the ears with non-B tracings in which curve angle higher than 75 degrees were accepted as those without effusion. RESULTS: False positivity values of TYMP, reflectivity and curve angle and the combined test found in the ears with chronic retraction without effusion (29, 23, 19 and 35% respectively; chi(2)-test, P > 0.1) were significantly higher than normal ears (chi(2)-test, P < 0.001), but lowe than those of effusion (chi(2)-test, P<0.0001). Further, although negative predictivity values of TYMP, reflectivity and curve angle were found to be lower in these ear, compared to normal ears (chi(2)-test, P < 0.01), the combined test reached to a perfect negative predictivity, as much as in normal ears. On the other hand, positive predictivity values were decreased in the ears with chronic retraction without effusion by only reflectivity. CONCLUSIONS: By both TYMP and AR alone, it is more difficult to find out the ears without effusion among the ears clinically and otoscopically diagnosed as otitis media than to find out normal ears. Therefore, in clinical work, false positivity of these devices were higher, and their specificity and negative predictivity were lower; although the combined test solved problem of low negative predictivity, high number of false positive ears in clinical work, that is lower specificity, continues to be an unsolved problem by either TYMP or AR alone, or both together.

Accessory nerve function after modified radical and lateral neck dissections.

OBJECTIVES: Evaluate preoperative and postoperative electrophysiological changes related to the accessory nerve with reference to dissection technique, modified radical neck dissection, and lateral neck dissection. STUDY DESIGN: Prospective electrophysiological analysis of accessory nerve function in a total of 20 laryngeal carcinoma patients after neck dissection, 12 being lateral neck dissection (4 bilateral) and 8 being modified radical neck dissection. METHODS: Distal latencies, compound muscle action potentials, and electromyography findings were investigated before surgery and, in early and late postoperative periods in 20 laryngeal carcinoma patients. Results were evaluated by Student t test and chi2 test for intragroup and intergroup differences. RESULTS: In the lateral neck dissection group, postoperative distal latencies were longer, without statistical significance, whereas in the modified radical neck dissection group postoperative latencies were statistically longer. Postoperative compound muscle action potentials were significantly lower in both groups. Electromyographic work-up showed deterioration in early postoperative periods and improvement in late postoperative periods. When intergroup differences were compared, both postoperative compound muscle action potential and electromyographic findings were worse in the lateral neck dissection group. CONCLUSIONS: The accessory nerve function after modified radical neck dissection is better than function after lateral neck dissection because of increased stress applied to the nerve during retraction of the sternocleidomastoid muscle for achievement of a better exposed surgical field in lateral neck dissection.

Posterior fossa vestibular nerve section for the management of peripheral vertigo.

Patients with vertigo resistant to conservative treatment require surgical management. Between March 1991 and August 1996, vestibular nerve sections were performed in 108 patients with peripheral vertigo not responding to conservative treatment. The diagnoses were classic Ménière's disease in 96 patients and recurrent vestibulopathy in 12 patients. Combined retrosigmoid retrolabyrinthine (n = 106) and retrolabyrinthine (n = 2) approaches were used. Patients were grouped according to follow-ups of less than 2 years and more than 2 years. In the former group (n = 49), hearing preservation and vertigo control were achieved in 93.9% and 100%, respectively. In the latter group (n = 59) the rates were 89.8% and 96.6%, respectively. Overall complications were uncommon. Three patients had cerebrospinal fluid leakage and one had total hearing loss. According to our results, posterior fossa vestibular nerve section was found to be an effective treatment for the management of patients with intractable vertigo.

Predictive value of acoustic reflectometry (angle and reflectivity) and tympanometry.

OBJECTIVE: Tympanometry and acoustic reflectometry are suggested tools for confirmation of otoscopic diagnosis of secretory otitis media. The issues on sensitivity and specificity of both devices are contradictory. In this study, our purpose was to compare sensitivity and specificity of both devices and to look for whether it is possible to reach higher values by combining them. METHODS: This study included 150 normal ears and 150 ears with chronic effusion. In tympanometry, only B tracings were accepted as predictor of effusion. In acoustic reflectometry, reflectivity (cut point: 5) and curve angle with two cut-points (75 degrees and 90 degrees) were used. RESULTS: Acoustic reflectometry presented higher specificity by both reflectivity (cut point: 5) and by curve angle (cut point: 75 degrees) (99.33% by both) than tympanometry (92%) (chi2 analysis, P < 0.001). But, their sensitivities (65.33 and 78%) were lower than tympanometry (96%) (chi2 analysis, P < 0.001). With curve angle of 90 degrees, specificity of acoustic reflectometry decreased to 85.33%, sensitivity increasing to 97.33%, which was not different from tympanometry (chi2 analysis, P > 0.1). When data of curve angle and tympanometry were combined, specificity and sensitivity of the combined test were found to be 91.33 and 100%, respectively. CONCLUSIONS: (i) Acoustic reflectometry should not be proposed as a better device than tympanometry, because its test efficiency was not higher than tympanometry. (ii) The only advantage of AR (reflectivity > or = 5 and curve angle < or = 75 degrees) was its high specificity to effusion. In addition, higher curve angles than 90 degrees were found to be highly predictive for normal ears as much as tympanometry. But, predictivity of curve angle between 76 degrees and 90 degrees was low. (iii) When tympanograms and curve angle were combined, it was found that prediction of this combination for curve angles between 76 degrees and 90 degrees was perfect. (iv) We consider that both test devices provide complementary data to each other, which would be particularly important for screening studies and that they are good tools for confirmation of clinical impression, particularly for less experienced clinicians.

Functional results of Plastipore prostheses for middle ear ossicular chain reconstruction.

OBJECTIVE: Assessment of plastipore prostheses for middle ear ossicular chain reconstruction. Hearing results with total and partial Plastipore ossicular replacement prostheses (TORP and PORP) were evaluated in open- and closed-cavity operations. STUDY DESIGN: A retrospective review of 237 patients who underwent operation for chronic ear disease as well as ossiculoplasty with plastipore prostheses. In order to assess the functional results, only 156 of 237 patients were included in the study. Follow-up ranged from 6 to 46 months. METHODS: Canal wall up and canal wall down operations were performed. Either TORP or PORP ossiculoplasty was performed in each operation. An airbone gap closure to within 20 dB was considered successful. RESULTS: With TORPs, the airbone gap closure to within 20 dB was achieved in 43.1%, and similar results were obtained with PORPs in 63.3%. In canal wall down and canal wall up operations, the success rates were 55.8% and 55.7%, respectively. The best results were obtained with PORPs in canal wall down operations, with a success rate of 82%. The extrusion rate of the prostheses was 4.2%. CONCLUSION: Hearing results of PORPs are better than TORPs. In canal wall up and canal wall down operations similar hearing results are obtained. PORP ossiculoplasty in a canal wall down operation yields the most favorable hearing result.

Facial reanimation after temporal bone fracture.

Fracture of the temporal bone is usually associated with skull injury and the patient is initially seen in the emergency room. As a result the diagnosis of facial paralysis may be delayed. The aim of this study is to emphasize the importance of early diagnosis and treatment of facial paralysis in such cases. Between 1990 and 1996, sixteen patients with facial paralysis due to temporal bone fracture were operated on within one month of trauma. The surgical technique was selected on the basis of the location of fallopian canal involvement and the patients hearing status. Six patients had grade VI, 7 had grade V and 3 had grade IV facial weakness preoperatively. Twelve patients had serviceable hearing. 9 of them underwent facial decompression through the transmastoid approach and 3 were operated on via the middle fossa approach. Four patients with unserviceable hearing had the operation through the translabyrinthine route. Postoperatively, 15 out of sixteen patients gained normal facial function while one had grade III facial weakness. Severe grade and sudden onset facial paralysis after temporal bone fracture should be surgically corrected as early as possible. The site of involvement of the facial canal and patient's hearing status should be considered in deciding the type of surgery to be applied.