The Impact of the COVID-19 Pandemic on Bell's Palsy and Ramsay-Hunt Syndrome: A Multicenter Retrospective Study.

BACKGROUND: This article presents a comprehensive review of data on the impact of facial palsy during the coronavirus disease 2019 (COVID-19) pandemic. The possible causes and pathophysiological mechanisms of changes in the epidemiology of facial palsy during the COVID-19 pandemic are also discussed. METHODS: This multicenter retrospective cohort study included 943 patients diagnosed with Bell's palsy or Ramsay Hunt syndrome. This study compared patient demographics, comorbidities, symptoms, and treatments before the COVID-19 pandemic (from 2017 to 2019) and during the COVID-19 pandemic, from 2020 to 2022). RESULTS: Following the COVID-19 outbreak, there has been a significant increase in the number of cases of Bell's palsy, particularly among elderly individuals with diabetes. Bell's palsy increased after the COVID-19 outbreak, rising from 75.3% in the pre-COVID-19 era to 83.6% after the COVID-19 outbreak. The complete recovery rate decreased from 88.2% to 73.9%, and the rate of recurrence increased from 2.9% to 7.5% in patients with Bell's palsy. Ramsay Hunt syndrome showed fewer changes in clinical outcomes. CONCLUSION: This study highlights the impact of the COVID-19 pandemic on the presentation and management of facial palsy, and suggests potential associations with COVID-19. Notably, the observed increase in Bell's palsy cases among elderly individuals with diabetes emphasizes the impact of the pandemic. Identifying the epidemiological changes in facial palsy during the COVID-19 pandemic has important implications for assessing its etiology and pathological mechanisms of facial palsy disease.

The clinical availability of facial nerve enhancement in temporal bone MRI for the patients of idiopathic acute peripheral facial palsy.

PURPOSE: This study is to evaluate the duration of facial nerve enhancement in gadolinium-enhanced temporal bone MRI after the onset of acute facial palsy. METHODS: Gd-enhanced MRI imagines were examined in 13 patients with idiopathic acute facial palsy within 14 days after the onset. The degree of facial nerve function was measured according to the House-Brackmann (H-B) grading system at their first visit at outpatient clinic. The follow-up MRI was taken about 16.5 months (7-24 months) after onset of disease. The degree of facial nerve enhancement was measured with signal intensity (SI) which was quantitatively analyzed using the region-of-interest (ROI) measurements for each segment of the facial nerve. SI was statistically analyzed by comparing SI values of contralateral site and ipsilateral site using the paired t test with SPSS program. RESULTS: The gadolinium enhancement was statistically increased at labyrinthine segment and geniculate ganglion area of facial nerve at initial temporal bone MRI. The gadolinium enhancement was statistically decreased at all the segments of facial nerve except tympanic segment (p < 0.05) at follow-up MRI. CONCLUSIONS: The facial nerve enhancement in Gd-enhanced MRI images prolonged more than 21 months of the onset. The newly developed pathologic lesions of acute facial palsy especially occur at the site of labyrinthine and geniculate ganglion.

Functional evaluation of paratubal muscles using electromyography in patients with chronic unilateral tubal dysfunction.

Eustachian tube dysfunction is closely related to the development of otitis media and result from several factors including inflammation within the nasal cavity and nasopharynx, adenoid hypertrophy, cleft palate and nasopharyngeal carcinoma. To some extent, eustachian tube dysfunction may be related to weakness of the paratubal muscles, such as the tensor veli palatini and levator veli palatini muscles. The aim of the study is to find out myogenic factors in eustachian tube dysfunction using electromyography (EMG), and to evaluate the clinical feasibility of EMG. Ten patients with unilateral eustachian tube dysfunction were included in this study. The healthy side of each patient was used as a control. EMG tests on paratubal muscles were conducted under the view of a 30° endoscope or fiberoptic laryngoscope. EMG on the tensor veli palatini showed decreased amplitudes on the affected side in one patient during phonation. EMG on the levator veli palatini showed decreased amplitudes on the affected side in two patients during both deglutition and phonation, one patient during phonation only, and two patients during deglutition only. The only patient who had decreased amplitude on EMG of the tensor veli palatini also had decreased amplitude on EMG of the levator veli palatini. In conclusion, although it is generally accepted that the tensor veli palatini plays a major role in opening the eustachian tube, reduced activity of the levator veli palatini may be related to eustachian tube dysfunction. When assessing eustachian tube function, EMG is useful for evaluating myogenic factors.

Tinnitus in patients with profound hearing loss and the effect of cochlear implantation.

The objectives of this study were to characterize the features of tinnitus in patients with profound sensorineural hearing loss and to evaluate the effect of cochlear implantation (CI) on their tinnitus. Medical records were reviewed for 35 patients who underwent CI, and completed tinnitus questionnaire between March 2003 and August 2011. Of them, 22 had tinnitus prior to CI (62.9 %) and the tinnitus group was older than the non-tinnitus group (47.5 ± 15.1 vs. 28.9 ± 15.2). The mean tinnitus handicap inventory (THI) score of the tinnitus group was 50.5 ± 28.7 before surgery, and the mean THI score and visual analogue scale (VAS) scores for loudness, annoyance, effect on life, and awareness decreased significantly after CI, with a mean follow-up period of 10.7 months. Tinnitus was completely eliminated in ten patients (45.5 %) and THI scores decreased in all patients. In a correlation analysis of the decrease in THI scores, preoperative VAS scores for loudness, awareness, effect on life, and annoyance, as well as preoperative THI scores, were highly correlated with the degree of decrease in THI scores postoperatively. The auditory performance of patients older than 40 years did not differ from that of younger patients, but their tinnitus was more improved after CI. In conclusion, tinnitus is a common complaint in patients with cochlear implants, and is more prevalent in elderly implantees. In the present study, CI improved tinnitus in all patients, although the most severe cases had the greatest benefit.

Factors Affecting the Extrusion Rate and Complications After Ventilation Tube Insertion: A Multicenter Registry Study on the Effectiveness of Ventilation Tube Insertion in Pediatric Patients With Chronic Otitis Media With Effusion-Part II.

OBJECTIVES: The impacts of ventilation tube (VT) type and effusion composition on the VT extrusion rate and complications in children with otitis media remain unclear. This part II study evaluated the factors affecting the extrusion rate, recurrence rate, and complications of VT insertion. METHODS: A prospective study was conducted between June 2014 and December 2016 (the EVENT study [analysis of the effectiveness of ventilation tube insertion in pediatric patients with chronic otitis media]), with follow-up data collected until the end of 2017. Patients aged <15 years diagnosed with otitis media with effusion who received VT insertion were recruited at 15 tertiary hospitals. The primary outcomes were time to extrusion of VT, time to effusion recurrence, and complications. RESULTS: Data from 401 patients were analyzed. After excluding the. RESULTS: of long-lasting tubes (Paparella type II and T-tubes), silicone tubes (Paparella type I) exhibited a significantly longer extended time to extrusion (mean, 400 days) than titanium tubes (collar-button-type 1.0 mm: mean, 312 days; P<0.001). VT material (hazard ratio [HR], 2.117, 95% confidence interval [CI], 1.254-3.572; P=0.005), age (HR, 3.949; 95% CI, 1.239-12.590; P=0.02), and effusion composition (P=0.005) were significantly associated with the time to recurrence of middle ear effusion. Ears with purulent (mean, 567 days) and glue-like (mean, 588 days) effusions exhibited a shorter time to recurrence than ears with serous (mean, 846 days) or mucoid (mean, 925 days) effusions. The revision VT rates during follow-up were 3.5%, 15.5%, 10.4%, and 38.9% in ears with serous, mucoid, glue-like, and purulent effusions, respectively (P<0.001). The revision surgery rates were higher among patients aged <7 years than among those aged ≥7 years. CONCLUSION: Silicone tubes (Paparella type I) were less prone to early extrusion than titanium 1.0 mm tubes. VT type, patient age, and effusion composition affected the time to recurrence of effusion.

A comparative analysis of intranasal volume and olfactory function using a three-dimensional reconstruction of paranasal sinus computed tomography, with a focus on the airway around the turbinates.

The aim of this study was to investigate the relationship between the intranasal airway around the turbinates and olfactory function. In total, 32 nostrils of 16 patients who were awaiting septal surgery were involved in this study. For measurements of the volume of the nasal cavity, paranasal sinus computed tomography scans were performed and reconstructed into three-dimensional images. The Butanol Threshold Test and Cross-Cultural Smell Identification Test were used to evaluate olfactory function. The results were analyzed with Pearson's test. The volume around the turbinates was significantly correlated with the olfactory threshold. However, olfactory identification had no significant correlation with each volume. The airway around the turbinates is very important for nasal airflow and its volume influences olfactory function. Understanding such relationships may help in preserving or improving olfactory function in septal, turbinate or sinus surgery. Further studies are needed regarding the relationships between not only the volume of the nasal cavity and nasal airflow, but also between nasal volume changes and olfactory function.

Comparative study of the pneumatization of the mastoid air cells and paranasal sinuses using three-dimensional reconstruction of computed tomography scans.

PURPOSE: The purpose of this study was to investigate the relationship between the pneumatization of mastoid air cells and PNS using three-dimensional (3D) reconstruction of computed tomography (CT) scans of the PNS. METHODS: A retrospective review of PNS CT scans from 60 cases was performed. Patients with evidence of sinusitis or mastoiditis, or a history of head trauma, were excluded from the study. Volumes were measured using 3D reconstruction based on axial images of 1 mm thickness. Volumes of the mastoid air cells (right and left), frontal sinus, sphenoid sinus, and maxillary sinuses (right and left) were obtained and compared using statistical analysis. RESULTS: The volume of mastoid air cells and sinuses did change with age, but the volumes of male subjects were larger than those of females. There was a positive correlation between the pneumatization of mastoid air cells and that of the sphenoid sinus; however, no relationship was observed between the volume of mastoid air cells and that of the maxillary sinuses. CONCLUSIONS: This study examined whether a similarity in pneumatization exists between the mastoid air cells and PNS of individuals; these results may be useful in understanding the normal and pathological conditions of both structures.

Influence of Cochlear Dead Regions on Hearing Outcome in Sudden Sensorineural Hearing Loss.

OBJECTIVE: The aims of this multicenter study were to prospectively evaluate the prevalence of dead regions (DRs) in sudden sensorineural hearing loss (SSNHL) and compare the clinical characteristics and hearing outcomes of SSNHL according to the presence of DRs. STUDY DESIGN: Prospective study. SETTING: Multicenter study. PATIENTS AND METHODS: The threshold-equalizing noise (TEN) test was prospectively performed on a total of 130 patients diagnosed with SSNHL. All patients received systemic steroid therapy and/or intratympanic steroid injection within 1 month after onset. Pure-tone audiograms and the TEN test were conducted before and after steroid treatment. Age, sex, side of affected ear, recurrence, onset of symptoms, presence of dizziness, and comorbid diseases were also collected. The prevalence of DRs in SSNHL and clinical factors related to the DRs were assessed. Hearing outcomes for SSNHL according to DRs were evaluated in 68 patients who followed a pure-tone audiogram. RESULTS: The overall prevalence of one or more DRs in SSNHL evaluated using the TEN test was 20.8% (27/130 subjects) and the overall frequency-specific prevalence of DR was 6.7% (61/910 DRs). Although the DRs (+)and DR (-) groups had similar initial pure-tone thresholds, the DRs (+) group had significantly worse initial WRS compared to the DRs (-) group (p = 0.015). The presence of DRs was not associated with hearing recovery in a multivariate logistic regression model, but it was significantly associated with the degree of hearing gain in a multivariate linear regression model (p = 0.018). CONCLUSIONS: The presence of DRs can be considered one of the poor prognostic factors for SSNHL and the TEN test may contribute to assess the prognosis of SSNHL in clinical settings.

Is turbinate surgery necessary when performing a septoplasty?

Many otolaryngologists perform septoplasty with or without turbinate surgery and the surgical method relies largely on the surgeon's clinical judgment. This study used computed tomography (CT) of the sinuses of 20 patients to examine the correlation between a unilateral deviated nasal septum and compensatory hypertrophy of the contralateral inferior turbinate to suggest guidelines for septal and turbinate surgery. The thickness of the mucosa and conchal bone, the projection angle of the conchal bone, and the distances between the conchal bone, and lateral nasal line and median line were measured. The volume of the inferior turbinate was measured from the three-dimensional reconstruction. Each measurement was compared with those of the nasal cavity on the contralateral and of normal control subjects. The inferior turbinate on the concave side had a significantly greater volume, including the thickness of medial mucosa and the thickness and projection angle of conchal bone. Septoplasty and concomitant inferior turbinate surgery to manipulate conchal bone and soft tissues are necessary for treatment of those patients with unilateral nasal septal deviation and compensatory hypertrophy of the contralateral inferior turbinate.

The Clinical Characteristics and Surgical Outcomes of Carcinoma of the External Auditory Canal: A Multicenter Study.

OBJECTIVE: To analyze the clinical characteristics and evaluate the surgical outcomes of carcinoma of the external auditory canal (CEAC). MATERIALS AND METHODS: Overall, 31 patients from four multicenter hospitals, who were diagnosed and surgically treated for CEAC in 2009-2014, were enrolled for this retrospective study. Medical records were reviewed to determine cancer stage according to the Pittsburgh classification. Clinical data of age, sex, site, initial symptoms, surgery extent, postoperative complications including recurrence, follow-up period, and current patient status were collected for analysis. Five-year cumulative survival rate was obtained using Kaplan-Meier method. RESULTS: At initial diagnosis, 22 patients were in the early stages (stage I: 15; stage II: 7) and 9 patients were in the advanced stages (stage III: 1; stage IV: 8). Lymph node metastasis was present in 5 patients and distant metastasis in 2. Of the 31 patients, 4 patients died (stage II: 1, stage IV: 3) during the follow-up period. Early-stage patients showed 100% 5-year estimated cumulative survival rate, whereas the advanced-stage patients showed 5-year estimated survival rate of 53.6% (p=.006). The overall survival rate of all enrolled patients was 90.3%. Although 5-year estimated disease-free survival rate of stage I was 100.0%, that for stage II was low at 30.0% because of considerable recurrences. CONCLUSION: The results of this multicenter study suggest that more aggressive treatment modality, including adjuvant therapy, is necessary for patients with CEAC with Pittsburgh stage II or more.

An Uncommon Presentation of Human Otoacariasis by Haemaphysalis longicornis.

Ticks are obligate parasites on animals and sometimes humans. They usually suck the blood of the hosts and can carry various infectious diseases as a vector. Otoacariasis is the presence of ticks and mites within the ear canal and relatively common in domestic and wild animals. However, tick infestations of human ear canals are rarely reported in the scientific literature and hardly occur in developed countries. Herein, we report a rare case of otoaracariasis involving Haemaphysalis longicornis . A 9-year-old girl living in a suburb presented with otalgia of left ear for 1 day. Otoscopic examination revealed a huge insect occluding the tympanic membrane. Tick removal and washing of external auditory canal was done successfully. The causative tick was identified as the H. longicornis. To our knowledge, this is the first reported case of human otoacariasis by a H. longicornis in Korea.

Microbiological Results From Middle Ear Effusion in Pediatric Patients Receiving Ventilation Tube Insertion: Multicenter Registry Study on the Effectiveness of Ventilation Tube Insertion in Pediatric Patients With Chronic Otitis Media With Effusion: Part I.

OBJECTIVES: The aim of this multicenter registry study was to investigate the effectiveness of ventilation tube insertion and the microbiology of otitis media with effusion (OME) in children. This part I study was conducted to evaluate the microbiological profile of children with OME who needed ventilation tube insertion. METHODS: Patients <15 years old who were diagnosed as having OME and received ventilation tube insertion were prospectively enrolled in 16 tertiary hospitals from June 2014 to December 2016. After excluding patients with missing data, the data of 397 patients were analyzed among a total of 433 enrolled patients. The clinical symptoms, findings of the tympanic membrane, hearing level, and microbiological findings were collected. RESULTS: In 103 patients (25.9%), antibiotics were used within 3 weeks before surgery. Ventilation tube insertion was performed in a total of 710 ears (626 in both ears in 313 patients, 55 in the left ear only, and 29 in the right ear only). Culture of middle ear effusion was done in at least one ear in 221 patients (55.7%), and in a total of 346 ears. Only 46 ears (13.3%) showed positive results in middle ear effusion culture. Haemophilus influenzae (17.3%, followed by coagulase-negative Staphylococcus and Staphylococcus auricularis) was the most common bacteria detected. CONCLUSION: H. influenzae was the most commonly found bacteria in middle ear effusion. Relatively low rates of culture positivity were noted in middle ear effusion of patients with OME in Korea.

Hearing outcome of sudden sensorineural hearing loss: long-term follow-up.

OBJECTIVE: To evaluate the time-dependent progress and delayed improvement in patients who were treated with combination therapy including oral corticosteroid for idiopathic sudden sensorineural hearing loss. STUDY DESIGN AND SETTING: This retrospective study at a secondary referral and university-based center included 156 patients who were treated by 10-day course of admission therapy and followed for at least three months. RESULTS: Of 121 patients who recovered over three months of follow-up, 45.5% showed a delayed recovery after the end of 10-day course of therapy. Of these 55 patients, 78.2% recovered within one month, 5.5% recovered within one to two months, 12.7% recovered in two to three months, and 3.6% recovered later than three months after discharge. CONCLUSIONS: This study describes the long-term results for a three-month retrospective series of 156 patients diagnosed with idiopathic sudden sensorineural hearing loss, although this result should be further studied by additional research.

Analysis of prognostic factors in Bell's palsy and Ramsay Hunt syndrome.

OBJECTIVE: This study evaluated the prognostic factors in Bell's palsy and Ramsay Hunt syndrome (HZO). METHODS: A retrospective, institutional review board-approved study at a university-based hospital. A total of 81 patients consisting of 55 Bell's palsy patients and 26 HZO patients were enrolled in this study. The treatment consisted uniformly in all cases, and acyclovir was administered in the case of Ramsay Hunt syndrome. All patients were followed up until they recovered or for least up 6 months. RESULTS: The recovery rates to House-Brackmann grade II or better were 96.3% in those with Bell's palsy and 84.6% in those with HZO. In the HZO cases, older patients had a poorer initial and final status, and less chance of making a complete recovery than the younger patients. The HZO patients without diabetes mellitus had a higher chance of recovery, a higher chance of complete recovery, and a better final status. In addition, HZO patients without essential hypertension had a higher degree of recovery. HZO patients not suffering from vertigo had a higher chance of recovery. CONCLUSION: There was no prognostic factor found in the Bell's palsy patients in this study. The prognostic factors of HZO were age, diabetus mellitus, essential hypertension and vertigo.

Evaluation of temporal bone pneumatization with growth using 3D reconstructed image of computed tomography.

OBJECTIVE: To evaluate temporal bone pneumatization with growth using 3D reconstructed computed tomography (CT) images. PATIENTS AND METHODS: Eighty-four temporal bones of 42 patients under the age of 16 years who had undergone head and facial bone CT were included in this retrospective study. The bony growth of the temporal bone and the head size were evaluated with horizontal- and vertical-plane CT images. Pneumatization of the temporal bone was investigated with 3D reconstruction software using axial CT images, dividing them as follows: medially, anterosuperiorly, posterolaterally, and inferiorly. Pneumatization of each individual part was compared with that of other parts and was also evaluated according to the aging process. RESULTS: The mean pneumatization was measured as 1696.7mm3 in patients aged under 2 years, 3609.1mm3 in those aged 2-4 years, 5351.1mm3 in those aged 5-7 years, 7295.9mm3 in those aged 8-10 years, 7797.5mm3 in those aged 11-13 years, and 8526.6mm3 in those aged 14-16 years. The degree of temporal bone pneumatization of each part was correlated with that of other parts (p<0.05). The volume of pneumatization increased with growth of the temporal bone and with aging. The degree of pneumatization of specific parts might be related to developmental periods. CONCLUSION: The pneumatization of one part might affect the pneumatization of other nearby parts, or all parts might be affected by the same driving force of pneumatization.

Deep temporal fascial-periosteal flap for canal wall down mastoidectomy.

It is very important to make a safe, dry, trouble-free ear for the canal wall down mastoidectomy. Although fascia graft is the most common material used for the repair of the perforated tympanic membrane, it is usually too small to cover the whole mastoid cavity in canal wall down mastoidectomy. The presence of exposed bone delays the epithelialization and results in prolonged otorrhea. We present a new simple technique that uses a postauricular, inferiorly based pedicled flap. Although our deep temporalis fascial-periosteal flap is not bulky, it is large enough to obliterate a sclerotic mastoid cavity without the need for additional flaps. It shrinks much less than a muscular flap during the healing period. In addition to reducing the cavity volume, this flap promotes the epithelialization over the bone and the shortening of the healing time. Although only a small number of patients were included in this study, coverage of a canal wall down mastoid cavity by a deep temporalis fascial-periosteal flap is expected to be a reliable and effective technique that results in a dry, trouble-free mastoid cavity.

The analysis of maxillary sinus aeration according to aging process; volume assessment by 3-dimensional reconstruction by high-resolutional CT scanning.

OBJECTIVE: To evaluate change of the maxillary sinus volume according to patient age and gender by using a 3-dimensional (3-D) reconstruction of computed tomography images. STUDY DESIGN AND SETTING: One hundred seventy-three people (totaling 238 maxillary sinuses) who had undergone paranasal sinus CT scan between December 2000 and November 2003 and had no evidence of inflammation or hypoplasia in the CT finding and had no specific history of paranasal sinus surgery or maxillofacial trauma were retrospectively analyzed. The 3-D reconstruction images were obtained by using a surface-rendering technique (Vworks; CybeMed, Seoul, Korea) on a personal computer. The mean volume of maxillary sinus was evaluated according to patient chronologic age and gender. The ratio of the maximum horizontal and half-horizontal extension for the estimation of the morphological change of maxillary sinus and the degree of descent of the sinus below the nasal floor were evaluated in the 3-D image. RESULTS: The development of the maxillary sinus continued until the 3rd decade in males and until the 2nd decade in females. The mean maxillary sinus volume in early adults was 24,043 mm 3 (males) and 15,859.5 mm 3 (females). There was a significance difference in the sinus volume ( P < 0.05) according to gender, and there was a significant difference in the maxillary sinus volume according to age before it reached maximum. After its maximum growth period, however, there was no significant difference in the volume change of maxillary sinus and the descent below the nasal floor between two adjacent groups. CONCLUSIONS: The growth of the maxillary sinus continues until the 3rd decade in males and the 2nd decade in females. Therefore, a maxillary sinus operation affecting the bony structures before these ages might affect the development of the sinus and needs to be performed carefully.

Clinical feasibility of the new technique of functional 3D laryngeal CT.

CONCLUSIONS: Functional 3D laryngeal CT (F3DLxCT) is an informative tool for visualizing the active changes in length, tension and mass of the vocal folds for pitch control. Furthermore, volume defects and level differences of paralyzed vocal folds are easily detectable with this new technique. OBJECTIVE: To evaluate the clinical feasibility of F3DLxCT images, which can provide clear coronal images of the vocal fold in each anteroposterior direction during phonation and in the resting state. MATERIAL AND METHODS: FLxCT images were reconstructed to three dimensions to visualize laryngeal motion. FLxCT was performed in four normal controls and in four patients with unilateral vocal fold paralysis in the resting state and during phonation with three vowel sounds of different pitch. 3D images were reconstructed with segmentation and a surface-rendering algorithm on a PC, using the DICOM file of axial images. RESULTS: The dynamic vocal fold 3D image during phonation could visualize that the thickness and volume were decreased in relatively to the pitch increase. Typical subglottic shoulder-like image formation and ventricular widening were noted with the high-pitch tone.

A case of osteoma with cholesteatoma in the external auditory canal.

Osteoma in the external auditory canal (EAC) is an uncommon benign lesion, which presents as a solitary, unilateral, and slow-growing pedunculated mass in the outer half of the bony canal. It is usually asymptomatic; but symptoms can arise if a canal obstruction occurs. External canal cholesteatoma is also a rare lesion of the external auditory canal. Cholesteatoma of the external auditory canal may arise via several mechanisms. However, an occlusion or narrowing of the external auditory canal is the basic pathogenesis. The association of an osteoma with a cholesteatoma is extremely rare, and there have been very few reports published. We encountered a rare case of a 49-year-old man with an osteoid osteoma that was complicated by a cholesteatoma in the external auditory canal. The canal wall down mastoidectomy and tympanoplasty successfully removed the osteoma and the cholesteatoma, and no recurrence or complications had occurred in the first 6 months postoperatively.

Three-dimensional reconstruction based on images from spiral high-resolution computed tomography of the temporal bone: anatomy and clinical application.

The aim of this study was to investigate the usefulness of a three-dimensional (3D) reconstruction of computed tomography (CT) images in determining the anatomy and topographic relationship between various important structures. Using 40 ears from 20 patients with various otological diseases, a 3D reconstruction based on the image data from spiral high-resolution CT was performed by segmentation, volume-rendering and surface-rendering algorithms on a personal computer. The 3D display of the middle and inner ear structures was demonstrated in detail. Computer-assisted measurements, many of which could not be easily measured in vivo, of the reconstructed structures provided accurate anatomic details that improved the surgeon's understanding of spatial relationships. A 3D reconstruction of temporal bone CT might be useful for education and increasing understanding of the anatomical structures of the temporal bone. However, it will be necessary to confirm the correlation between the 3D reconstructed images and histological sections through a validation study.