Prevalence of Superior Semicircular Canal Dehiscence in Coronal Images of Temporal Bone Computed Tomography and Its Diagnostic Value in Korean Population / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: This study aimed to analyze the prevalence of superior semicircular canal dehiscence (SSCD) in the coronal images of high-resolution temporal bone computed tomography (TBCT) and to evaluate the diagnostic accuracy of coronal images for SSCD syndrome. SUBJECTS AND METHOD: We retrospectively reviewed high-resolution TBCT scans of 217 patients (434 ears) with SSCD due to various causes. The dehiscence ratio (slices showing dehiscence/total slices showing the superior semicircular canal) in the coronal images of TBCT was calculated, and the optimal cutoff value for the diagnosis of SSCD syndrome was determined using the receiver operating characteristics (ROC) curve. RESULTS: Of the 434 ears, 64 (14.7%) presented SSCD in more than one slice of the coronal images of TBCT, but only three patients (0.7%) were confirmed with SSCD syndrome. Based on the ROC curve analysis for the dehiscence ratio of 64 ears, the optimal cutoff value for the diagnosis of SSCD syndrome was 0.67 with 100% sensitivity and 90.2% specificity. CONCLUSION: The majority of cases diagnosed with SSCD syndrome using the coronal images of TBCT were asymptomatic or false-positive. The dehiscence ratio in the coronal images of TBCT combined with a typical symptom can be a highly sensitive and specific diagnostic tool for SSCD syndrome.

Correction of the Deviated Nose in Korean Rhinoplasty / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The surgical techniques based on the classification system based on Western individuals for the correction of deviated nose should be modified because of the differences in the anatomy of the nose for Korean individuals. To evaluate the usefulness of a classification system that has been designed for the esthetics and deviated nose of Korean individuals, we used that to analyze the surgical outcomes of rhinoplasty for deviated nose for 76 Korean patients. SUBJECTS AND METHOD: Seventy six patients who underwent rhinoplasty for deviated nose between January 2010 and June 2016 were reviewed retrospectively. All patients were classified with Jang's classification system and surgical techniques were analyzed according to the classification. Surgical outcomes were evaluated based on the preoperative and postoperative photo taken of the patient's nose. The degree of nasal deviation, tip projection index, nasofrontal angle and columellar-labial angle were measured. RESULTS: Deviated nose was classified into type I (34%), type II (26%), type III (13%), type IV (9%), and type V (17%). Preoperative and postoperative anthropometric measurements revealed that the mean degree of deviation changed from 8.84° to 3.01° (p < 0.01); the tip projection index changed from 0.54 to 0.58 (p < 0.01), and the degree of nasofrontal angle changed from 131.55° to 133.14° (p < 0.01). Aside from the residual deviations, complications included a shifting of the dorsal graft, an inverted V-deformity from the depression of the middorsum after the spreader graft and incomplete hump removal. CONCLUSION: Analysis based on the said classification system and personal esthetics showed good surgical outcomes for rhinoplasty to correct deviated nose. Therefore, it would be helpful to treat Korean patients for the correction of deviated nose by using both classification system and personal esthetics that are based on Korean individuals.

Significance of 125 Hz Pure-Tone Thresholds for Acute Low Frequency Sensorineural Hearing Loss / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: To analyze the 125 Hz pure-tone thresholds in patients with acute low frequency sensorineural hearing loss (LFHL) and to investigate the value of 125 Hz thresholds for the assessment of LFHL. SUBJECTS AND METHOD: Hearing tests including 125 Hz pure-tone were performed in 91 patients with acute LFHL ≤500 Hz and in 46 subjects with normal hearing. Patients with sudden sensorineural hearing loss or Meniere's disease were excluded. Inter-group and intra-group comparison of 125 Hz was made between LFHL and the control groups. RESULTS: There was a significant difference of mean pure-tone thresholds at 125 Hz between the acute LFHL and the normal groups (39.8±8.9 vs. 14.3±6.7 dB). Eight (8.8%) patients in the LFHL group showed normal thresholds at 125 Hz, but all other subjects were normal at 125 Hz in the control group. None with the average hearing thresholds at 250 and 500 Hz ≥40 dB had normal threshold at 125 Hz. There was a significant correlation between 125 Hz and other low frequencies in the LFHL group (250 Hz; r=0.81, 500 Hz; r=0.63). CONCLUSION: Not all patients with acute LFHL show abnormal hearing threshold at 125 Hz although every subject with normal hearing is within the normal limits at 125 Hz. Threshold assessment should be made at 125 Hz when a mild LFHL exists in the conventional pure tone audiometry.

The Normative Value of Acceptable Noise Level Test for Korean Young Listeners with Normal Hearing and Its Relationship with Auditory Brainstem Response Latency / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Acceptable noise level (ANL) test has been developed as a method to measure the background noise acceptance when listening to speech presented at the most comfortable level. The study was aimed to investigate normal-hearing in young subjects’ performance on ANL test and to evaluate the relationship between ANL and auditory evoked potentials. SUBJECTS AND METHOD: Fifty-three young adults (23 male and 30 female; aged 21 to 39 years) with normal hearing participated in this study. ANL and auditory brainstem response (ABR) tests were administered to subjects who were certified by pure tone audiometry that they had normal hearing threshold. RESULTS: The ANL test showed a large inter-subject variability in the acceptance of back-ground noise, ranging from -5 to 15 dB with the mean of ANL of 5.0±4.1 dB (4.5±4.5 dB in male and 5.4±3.8 dB in female). The mean most comfortable listening level was 35.2±5.3 dB, and the mean background noise level was 30.2±6.1 dB. There were no significant differences between male and female in the parameters of ANL test. There were no differences between the subjects with low versus high ANLs and ABR latencies. CONCLUSION: We obtained the normative data of the ANL test administered to Korean young adults with normal hearing. There is no relationship between ANL and the latency of ABR in this study population.

Nasal Septal Swell Body: Radiologic Characteristics and the Relationship to Nasal Septal Deviation / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: To analyze the radiographic dimensions of the nasal septal swell body and to find a relationship between the septal body (SB) thickness and the degree of septal deviation. SUBJECTS AND METHOD: One hundred eighteen ostiomeatal units computed tomographic scans were reviewed retrospectively. Dimensions of the SB, distances to other landmarks and the degree of septal deviation were measured. RESULTS: The SB was 4.7 mm thick on the average, with the mean width of 11.4±1.7 mm, the height of 18.2±3.4 mm, and the length of 25.1±4.6 mm. The point of greatest prominence of SB was 23.7±2.7 mm from the nasal floor, which is 1.8±2.2 mm lower than the rhinion; it is also 5.0±2.6 mm anterior to the caudal end of the middle turbinate, and 4.5±2.8 mm posterior to the caudal end of the inferior turbinate. In 62 of the 78 cases with septal deviation, the SB was larger on the side opposite the deviation. The mean difference in the SB thickness of ipsilateral and contralateral to a septal deviation was 3.4 mm, 2.3 mm and 1.4 mm, for cases with severe, moderate and mild septal deviation, respectively. The difference in SB thickness was found to correlate with the degree of septal deviation. CONCLUSION: The SB is a structure of 11×18×25 mm in size, and like inferior turbinate, it is more prominent contralateral to a septal deviation. SB, situated in the nasal valve region, may have a role in regulating nasal airflow and may contribute to nasal obstruction.

The Effect of High Frequency Sensorineural Hearing Loss on Auditory Temporal Resolution: Gaps-In-Noise Test Performance in Older and Young Adults with Normal Hearing / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Auditory temporal resolution, which refers to the time-related aspects of acoustic processing, can be evaluated by the Gaps-In-Noise (GIN) test. We investigated whether the presence of high frequency sensorineural hearing loss (HF-SNHL) affects the temporal resolution of GIN performance in older adults with normal hearing. SUBJECTS AND METHOD: Hearing tests including the GIN test were performed in 87 subjects with normal pure tone average. The GIN threshold and percentage of correct answers were compared among 4 groups of participants; older adults with normal hearing (n=18), older adults with HF-SNHL (n=24), young adults with normal hearing (n=24) and young adults with HF-SNHL (n=21). RESULTS: There was no significant difference in the mean GIN thresholds between the HF-SNHL group (5.8+/-0.8 msec) and the normal hearing group (6.0+/-0.8 msec) in older adults, whereas the mean GIN thresholds of HF-SNHL group was higher than that of the normal group in young adults (4.6+/-0.3 msec vs. 4.2+/-0.5 msec, p<0.05). The mean percentage of correct answers of HF-SNHL group (62.5+/-5.5%) was not significantly different from that of the normal hearing group (60.6+/-3.9%) in the old, unlike in the young (71.3+/-4.0% with HF-SNHL vs. 76.9+/-4.3% with normal hearing, p<0.05). Age only showed a significant correlation with the GIN performance. Neither the GIN threshold nor the GIN perception level had any relation with the presence of HF-SNHL in older adults. CONCLUSION: We found no evidence that supported the influence of HF-SNHL on auditory temporal resolution in older adults. These results imply that HF-SNHL may be of little importance in gap detection after age-related changes in central auditory system.

Prevalence of Onodi Cells in Korean Based on Computed Tomography / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The Onodi cell is the posterior-most ethmoid air cell that lies superior to the sphenoid sinus, and has intimate relationship with the optic nerve. The aim of this study was to evaluate Onodi cell prevalence, protrusion and bony dehiscence of the optic nerve in Korean population using computed tomography (CT). SUBJECTS AND METHOD: A retrospective analysis was performed on 129 Korean patients who consecutively underwent CT between January 2014 and December 2014. The presence of Onodi cells and protrusion and bony dehiscence of the optic nerve were analyzed using 3-dimensional CT images. RESULTS: A total of 70 males and 59 females were studied. Onodi cells were present in 61 (47.3%) patients but in 88 CT slides (34.1%); this consisted of 27 Onodi cells found bilaterally (44.3%), 18 on the right side only (29.5%), and 16 on the left only (26.2%). Of the total 61 patients with Onodi cells, the optic nerve protrusion and dehiscence were present in 34.4% and 23.8% of the studied CT slides. There was no statistically significant relationship between the presence of Onodi cells and protrusion and bony dehiscence of the optic nerve. CONCLUSION: In our study, Onodi cells were found in almost half of the patients. This prevalence is higher than previously reported in the literature. In patients with Onodi cells, the optic nerve protrusion and dehiscence were present in about 1/3 and 1/5 of the total slides, respectively. Therefore, the identification of these cells is essential prior to endoscopic sinus and skull base surgery to prevent potential complications.

Fatal Case of Klebsiella Meningitis Combined with Bilateral Sudden Sensorineural Hearing Loss: A Case Report and Literature Review / 대한이비인후과학회지

Bilateral sudden sensorineural hearing loss (SSNHL) is very uncommon. Unlike unilateral SSNHL, bilateral SSNHL is more closely associated with serious systemic diseases and shows a more severe degree of hearing loss, poorer hearing prognosis and more significant impairment in morbidity. Although meningitis is one of possible causes of bilateral SSNHL, only a few cases were reported. We present a case of fatal Klebsiella meningitis accompanied by bilateral SSNHL with a literature review.

Caudal Septal Extension Graft Using Nasal Septal Osteocartilaginous Graft / 대한이비인후과학회지

The septal extension graft from the septum has become a common method of correcting a small or drooping nose in Korea. It can provide superior tip projection and definition if there is a sufficient amount of cartilage and nasal septal stability. In our case, the caudal type septal extension graft was applied unilaterally using septal osteocartilaginous graft harvested in one piece during septoplasty. It was useful in patients who needed septal extension graft in spite of the insufficient amount of available septal cartilage. For those patients, it could be used to achieve the cephalic rotation of drooping tip and the strengthening of septal support effectively. The nasal septal osteocartilaginous graft may serve as an alternative material for conchal cartilage or costal cartilage for caudal septal extension graft if the stable nasal support is maintained and the harvested graft is applied appropriately.