A 3D and Explainable Artificial Intelligence Model for Evaluation of Chronic Otitis Media Based on Temporal Bone Computed Tomography: Model Development, Validation, and Clinical Application.

BACKGROUND: Temporal bone computed tomography (CT) helps diagnose chronic otitis media (COM). However, its interpretation requires training and expertise. Artificial intelligence (AI) can help clinicians evaluate COM through CT scans, but existing models lack transparency and may not fully leverage multidimensional diagnostic information. OBJECTIVE: We aimed to develop an explainable AI system based on 3D convolutional neural networks (CNNs) for automatic CT-based evaluation of COM. METHODS: Temporal bone CT scans were retrospectively obtained from patients operated for COM between December 2015 and July 2021 at 2 independent institutes. A region of interest encompassing the middle ear was automatically segmented, and 3D CNNs were subsequently trained to identify pathological ears and cholesteatoma. An ablation study was performed to refine model architecture. Benchmark tests were conducted against a baseline 2D model and 7 clinical experts. Model performance was measured through cross-validation and external validation. Heat maps, generated using Gradient-Weighted Class Activation Mapping, were used to highlight critical decision-making regions. Finally, the AI system was assessed with a prospective cohort to aid clinicians in preoperative COM assessment. RESULTS: Internal and external data sets contained 1661 and 108 patients (3153 and 211 eligible ears), respectively. The 3D model exhibited decent performance with mean areas under the receiver operating characteristic curves of 0.96 (SD 0.01) and 0.93 (SD 0.01), and mean accuracies of 0.878 (SD 0.017) and 0.843 (SD 0.015), respectively, for detecting pathological ears on the 2 data sets. Similar outcomes were observed for cholesteatoma identification (mean area under the receiver operating characteristic curve 0.85, SD 0.03 and 0.83, SD 0.05; mean accuracies 0.783, SD 0.04 and 0.813, SD 0.033, respectively). The proposed 3D model achieved a commendable balance between performance and network size relative to alternative models. It significantly outperformed the 2D approach in detecting COM (P≤.05) and exhibited a substantial gain in identifying cholesteatoma (P<.001). The model also demonstrated superior diagnostic capabilities over resident fellows and the attending otologist (P<.05), rivaling all senior clinicians in both tasks. The generated heat maps properly highlighted the middle ear and mastoid regions, aligning with human knowledge in interpreting temporal bone CT. The resulting AI system achieved an accuracy of 81.8% in generating preoperative diagnoses for 121 patients and contributed to clinical decision-making in 90.1% cases. CONCLUSIONS: We present a 3D CNN model trained to detect pathological changes and identify cholesteatoma via temporal bone CT scans. In both tasks, this model significantly outperforms the baseline 2D approach, achieving levels comparable with or surpassing those of human experts. The model also exhibits decent generalizability and enhanced comprehensibility. This AI system facilitates automatic COM assessment and shows promising viability in real-world clinical settings. These findings underscore AI's potential as a valuable aid for clinicians in COM evaluation. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000036300; https://www.chictr.org.cn/showprojEN.html?proj=58685.

Role of mastoid pneumatization in predicting tympanoplasty results: Will it have the same importance in different age groups?

INTRODUCTION: There are several factors that seem to affect the surgical success rate of tympanoplasty, one of them being the pneumatization of the contralateral mastoid. In the current literature, several studies have been published with classification proposals for temporal bone pneumatization pattern. This study aims to evaluate the role of mastoid air cell extension in relation to the sigmoid sinus in predicting the surgical success of tympanoplasty. MATERIAL AND METHODS: This case-control study was performed on patients diagnosed with chronic otitis media (COM) who underwent type I tympanoplasty. The study group did not close the tympanic membrane, or there was a retraction or lateralization of the graft. The control group consisted of patients with surgical success. RESULTS: No statistically significant difference was found between groups regrading age, gender, perforation side/type, previous nasal surgery, and the presence of chronic otitis media in contralateral ear. A statistically significant difference was found when groups were compared in relation to the degree of pneumatization of the contralateral ear (p = 0.046), and this relationship does not seem to be influenced by age. CONCLUSION: To predict surgical success in terms of tympanic membrane closure in tympanoplasty, classification of contralateral ear pneumatization degree using the sigmoid sinus as a reference seems to be a valid and easy to apply method, and makes it possible to restrict the evaluation of pneumatization to the mastoid, a cell complex that does not seem to change with age.

Is it useful to use computerized tomography image-based artificial intelligence modelling in the differential diagnosis of chronic otitis media with and without cholesteatoma?

OBJECTIVE: Cholesteatoma is an aggressive form of chronic otitis media (COM). For this reason, it is important to distinguish between COM with and without cholesteatoma. In this study, the role of artificial intelligence modelling in differentiating COM with and without cholesteatoma on computed tomography images was evaluated. METHODS: The files of 200 patients who underwent mastoidectomy and/or tympanoplasty for COM in our clinic between January 2016 and January 2021 were retrospectively reviewed. According to the presence of cholesteatoma, the patients were divided into two groups as chronic otitis with cholesteatoma (n = 100) and chronic otitis without cholesteatoma (n = 100). The control group (n = 100) consisted of patients who did not have any previous ear disease and did not have any active complaints about the ear. Temporal bone computed tomography (CT) images of all patients were analyzed. The distinction between cholesteatoma and COM was evaluated by using 80% of the CT images obtained for the training of artificial intelligence modelling and the remaining 20% for testing purposes. RESULTS: The accuracy rate obtained in the hybrid model we used in our study was 95.4%. The proposed model correctly predicted 2952 out of 3093 CT images, while it predicted 141 incorrectly. It correctly predicted 936 (93.78%) of 998 images in the COM group with cholesteatoma, 835 (92.77%) of 900 images in the COM group without cholesteatoma, and 1181 (98.82%) of 1195 images in the normal group. CONCLUSION: In our study, it has been shown that the differentiation of COM with and without cholesteatoma with artificial intelligence modelling can be made with highly accurate diagnosis rates by using CT images. With the deep learning modelling we proposed, the highest correct diagnosis rate in the literature was obtained. According to the results of our study, we think that with the use of artificial intelligence in practice, the diagnosis of cholesteatoma can be made earlier, it will help in the selection of the most appropriate treatment approach, and the complications can be reduced.

[Analysis of spatial location of the malleus in patients with chronic otitis media based on 10 µm otology CT].

Objective: To assess the changes of the spatial location of the malleus in patients with chronic otitis media (COM) using 10 µm otology CT. Methods: Forty-five patients with COM (COM group, 45 ears) and 55 patients without external and middle ear disease (control group, 89 ears), who underwent 10 µm otology CT examination in Department of Radiology, Beijing Friendship Hospital, Capital Medical University from October 2020 to March 2021, were retrospectively collected during the same period. In the COM group, there are 20 males and 25 females, aged from 20 to 78 (40±14) years. In the control group, 29 were males and 26 were females, with age of 19 to 57 (32±11) years. The shortest distance between the malleus head and the upper wall, the distance between the outer edge of the malleus neck and the scutum, the distance between the outer edge of the malleus neck and the pars flaccida of the tympanic membrane, the shortest distance between the malleus head and the anterior wall, the shortest distance between the anterior process and the anterolateral wall, the shortest distance between the tip of the malleus handle and the promontory, and the shortest distance between the malleus head and the tympanic segment of the facial nerve were measured and compared between the two groups. Results: Compared with the control group, the head-upper wall distance (M (Q1, Q3)) (0.81 (0.48, 1.21) mm vs 0.57 (0.33, 0.90) mm) and the neck-scutum distance (1.79 (1.54, 2.13) mm vs 1.65 (1.48, 1.83) mm) were larger in the COM group (all P<0.05), and the neck-tympanic membrane distance (1.32 (1.15, 1.49) mm vs 1.45 (1.31, 1.59) mm) and the handle-promontory distance (1.56 (1.33, 2.09) mm vs 2.10 (1.74, 2.43) mm) were reduced in the COM group (all P<0.05, respectively). The neck-tympanic membrane distance on the left was larger than those on the right in the COM group (1.39 (1.19, 1.51) mm vs 1.21 (0.87, 1.31) mm, P<0.05). Conclusion: There are changes in the relative position of the malleus in patients with COM, which are helpful for further understanding the imaging manifestations in patients with COM.

Deep Learning in Automated Region Proposal and Diagnosis of Chronic Otitis Media Based on Computed Tomography.

OBJECTIVES: The purpose of this study was to develop a deep-learning framework for the diagnosis of chronic otitis media (COM) based on temporal bone computed tomography (CT) scans. DESIGN: A total of 562 COM patients with 672 temporal bone CT scans of both ears were included. The final dataset consisted of 1147 ears, and each of them was assigned with a ground truth label from one of the 3 conditions: normal, chronic suppurative otitis media, and cholesteatoma. A random selection of 85% dataset (n = 975) was used for training and validation. The framework contained two deep-learning networks with distinct functions: a region proposal network for extracting regions of interest from 2-dimensional CT slices; and a classification network for diagnosis of COM based on the extracted regions. The performance of this framework was evaluated on the remaining 15% dataset (n = 172) and compared with that of 6 clinical experts who read the same CT images only. The panel included 2 otologists, 3 otolaryngologists, and 1 radiologist. RESULTS: The area under the receiver operating characteristic curve of the artificial intelligence model in classifying COM versus normal was 0.92, with sensitivity (83.3%) and specificity (91.4%) exceeding the averages of clinical experts (81.1% and 88.8%, respectively). In a 3-class classification task, this network had higher overall accuracy (76.7% versus 73.8%), higher recall rates in identifying chronic suppurative otitis media (75% versus 70%) and cholesteatoma (76% versus 53%) cases, and superior consistency in duplicated cases (100% versus 81%) compared with clinical experts. CONCLUSIONS: This article presented a deep-learning framework that automatically extracted the region of interest from two-dimensional temporal bone CT slices and made diagnosis of COM. The performance of this model was comparable and, in some cases, superior to that of clinical experts. These results implied a promising prospect for clinical application of artificial intelligence in the diagnosis of COM based on CT images.

Pediatric otitic hydrocephalus: Report of two unusual cases and literature review.

Otitic hydrocephalus (OH) comprises a form of benign intracranial hypertension, which is secondary to otogenic lateral sinus thrombosis (LST). Only a small percentage of the patients with otogenic LST go into developing OH, and this may be associated with the multiplicity of anatomic variations of the cerebral venous drainage pathways. We present two pediatric cases of OH, along with a comprehensive review of the relevant literature. Both cases discussed in this article had concomitantly a rather rare anatomical variation; a high-riding, dehiscent jugular bulb, which might have played a role in the development of their clinical syndrome. The pediatric population with this particular imaging finding should receive special attention. Clinical implications of this concurrence are fitly discussed.

Occult otitis media in dogs with chronic otitis externa - magnetic resonance imaging and association with otoscopic and cytological findings.

BACKGROUND: Identification of perpetuating factors, such as otitis media (OM), is important for the successful management of canine chronic otitis externa (OE). HYPOTHESIS/OBJECTIVES: Occult OM can occur in cases of chronic OE; a focused magnetic resonance imaging (MRI) examination is a useful tool in their management. ANIMALS: One hundred twenty one client-owned dogs presented for investigation and treatment of chronic OE between 2009 and 2018. METHODS AND MATERIALS: Mixed retrospective (74 dogs) and prospective (47 dogs) study of chronic OE cases without neurological signs, describing the MRI, otoscopic and cytological findings; comparing cases with and without MRI evidence of OM. RESULTS: A total of 123 MRI studies were analysed (two dogs scanned twice). A short, focused MRI scan allowed detection of inflammation of the mucosal bulla lining as well as excellent discrimination between avascular material and vascularised soft tissue in the tympanic cavity. OM was found in 41 of 197 (21%) ears with chronic otitis externa. On otoscopy, the tympanic membrane was intact in six of 41 ears (15%), ruptured in 16 of 41 (39%) and not visible in 14 of 41 (34%) [no data in five of 41 (12%)]. Analysis of cytological findings showed that the presence of rods was only associated with an increased likelihood of OM when found together with inflammatory cells. CONCLUSIONS AND CLINICAL IMPORTANCE: Occult OM is a not uncommon finding on MRI of dogs with chronic OE. A targeted MRI study ("bulla mini-scan") may be useful as part of the clinical investigations.

Optical Identification of Middle Ear Infection.

Ear infection is one of the most commonly occurring inflammation diseases in the world, especially for children. Almost every child encounters at least one episode of ear infection before he/she reaches the age of seven. The typical treatment currently followed by physicians is visual inspection and antibiotic prescription. In most cases, a lack of improper treatment results in severe bacterial infection. Therefore, it is necessary to design and explore advanced practices for effective diagnosis. In this review paper, we present the various types of ear infection and the related pathogens responsible for middle ear infection. We outline the conventional techniques along with clinical trials using those techniques to detect ear infections. Further, we highlight the need for emerging techniques to reduce ear infection complications. Finally, we emphasize the utility of Raman spectroscopy as a prospective non-invasive technique for the identification of middle ear infection.

Aural CT characteristics of American Cocker Spaniels have features of both mesaticephalic and brachycephalic breeds.

Otitis externa and otitis media are common in American Cocker Spaniels, however breed-specific aural CT descriptions are currently lacking. This prospective and retrospective, observational, analytical study aimed to describe quantitative CT characteristics of the horizontal ear canal and the tympanic bulla in American Cocker Spaniels versus similar-sized mesaticephalic dogs. We prospectively performed clinical examinations and aural CT scanning for 38 American Cocker Spaniels. Computed tomographic transverse area of the osseous horizontal ear canal (TA1), transverse area of the widest air-filled part of the cartilaginous horizontal ear canal (TA2), tympanic bulla volume, and tympanic bulla wall thickness were measured. The TA1 and TA2 measurements were compared with those of 23 retrospectively recruited, similar-sized mesaticephalic dogs that had undergone CT-scanning of the head for non-ear-related reasons. The TA1 and TA2 did not differ for healthy American Cocker Spaniels and mesaticephalic dogs. Severely affected American Cocker Spaniels had significantly smaller TA2 (P < .001). The intraclass correlation coefficient for intraobserver and interobserver repeatability was 0.972 and 0.983 for TA1 and 0.994 and 0.998 for TA2, respectively. Variation between individuals was subjectively noted in healthy and affected American Cocker Spaniels, but mean tympanic bulla volume was slightly smaller in relation to body weight, and the tympanic bulla wall was thicker than in previous reports for mesaticephalic dogs. The tympanic bulla wall appeared thicker rostro-ventrally than caudo-ventrally in 44% of the dogs. Our results imply that a relatively thick tympanic bulla wall may be a normal CT variation and should be interpreted cautiously in this breed.

Unilateral hearing loss in a 94-year-old patient.

A case report of a 94-year-old, previously well male patient who presented with fever thought to be caused by community acquired pneumonia, new unilateral hearing loss and reduced consciousness. Despite antibiotic treatment he continued to deteriorate. Brain imaging with computer tomography and magnetic resonance imaging revealed a left otomastoiditis with osteomyelitis of the skull base, associated with an adjacent subdural empyema. He was also found to have a venous sinus thrombosis, most likely secondary to otitis media. He was managed with intravenous antibiotics, anticoagulation, grommet insertion and a hearing aid and he made a good recovery. This case reminds us to consider otitis media in older patients who present with hearing loss and fever. Otitis media can lead to serious complications including subdural empyema and osteomyelitis of the skull base.

Endoscopic Tympanoplasty without Mastoidectomy for Active Mucosal Chronic Otitis Media with Mastoid and Tympanic Antrum Lesions: A Prospective Clinical Study.

OBJECTIVE: This study aims to assess the effectiveness of endoscopic tympanoplasty without mastoidectomy in the management of active mucosal chronic otitis media (COM) patients with mastoid and tympanic antrum lesions. METHODS: It is a prospective controlled study where 42 patients with active mucosal COM with mastoid and tympanic antrum lesions or normal aeration were recruited from the outpatient clinic of the otology department, Eye Ear Nose and Throat Hospital of Fudan University. All patients underwent endoscopic tympanoplasty without mastoidectomy by using the underlay technique with tragal cartilage graft with one side-perichondrium. The follow-up period was at least 3 months and results were evaluated in terms of graft uptake, ear dryness and hearing improvement. RESULTS: Statistics showed no significant difference in graft uptake between the mastoid and tympanic antrum lesions group (90.5%) and the normal aeration group (95.2%). There was no significant difference in ear dryness between the mastoid and tympanic antrum lesions group (95.2%) and the normal aeration group (100%). Hearing improvement was comparable in the 2 groups. CONCLUSION: Regardless of the occurrence of soft density shadows in temporal bone showed by high-resolution computerized tomography in the mastoid and tympanic antrum, mastoidectomy is an unnecessary procedure for dealing with active mucosal COM without cholesteatoma. Therefore, this study shows that endoscopic tympanoplasty without mastoidectomy may be applied to active mucosal COM without cholesteatoma.

Clinical techniques in Veterinary Dermatology: Regional anaesthesia of the canine ear.

BACKGROUND: Video otoscopy is a valuable tool for the diagnosis and treatment of otitis externa (OE) and otitis media (OM) in dogs. Procedures performed by video otoscopy often are painful and it can be challenging to maintain steady anaesthetic depth and provide smooth anaesthetic recovery. A multimodal approach to analgesia and anaesthesia is ideal to minimize complications associated with high doses of anaesthetic drugs while providing the patient with adequate analgesia. HYPOTHESIS/OBJECTIVE: To describe a technique for regional anaesthesia of the canine ear. ANIMALS: One canine cadaver, obtained as part of a teaching laboratory class for other clinical techniques, with institutional approval, was used for illustration purposes. RESULTS: Clinical technique for regional anaesthesia of the canine ear. CONCLUSIONS AND CLINICAL IMPORTANCE: Nerve blocks for regional anaesthesia are an important aspect of a multimodal anaesthetic approach. A technique for blocking the two major sensory nerves to the canine ear is described.

Computed tomographic characteristics of pneumolabyrinth in a French bulldog with otitis media and externa.

A four-year-old female French bulldog was presented for evaluation of acute, left-sided peripheral vestibular syndrome. Computed tomographic (CT) examination of the head revealed the presence of air within the left cochlea and vestibule, consistent with pneumolabyrinth. This was concurrent with ipsilateral otitis media and externa. Pneumolabyrinth is an uncommon finding in humans and is most frequently due to head trauma and temporal bone fracture. This is the first report describing pneumolabyrinth in a dog, apparently of nontraumatic origin in this case.

Effect of mastoid bone pneumatization on the conformation and depth of the sinus tympani, a high-resolution computed tomography study.

PURPOSE: To investigate the relationship between mastoid pneumatization and the conformation and depth of the sinus tympani (ST) in patients with chronic otitis media (COM), based on the high-resolution computed tomography (HRCT) scans. METHODS: Two hundred and two patients affected by COM were included in the study. The patients were divided into three groups according to the extent of mastoid pneumatization on HRCT scans; pneumatized (group 1), diploic (group 2) or sclerotic (group 3). The variation in the ST area (types A, B, C) was assessed using a radiomorphological classification based on the relationship between the medial boundary of the ST and the third portion of the facial nerve. Depth of the ST was calculated by measuring the distance between the medial boundary of the ST and medial boundary of the third portion of the facial nerve RESULTS: There was a statistically significant difference between the groups in terms of the type of ST (p < 0.001). The mean depths of the ST were 1.59 ± 0.82 mm (0.00-2.80 mm) in group 1, 1.10 ± 0.79 mm (0.00-3.00 mm) in group 2 and 0.53 ± 0.63 mm (0.00-2.60 mm) in group 3. The groups were significantly different in terms of the depth of the ST (p < 0.001). CONCLUSION: A well-pneumatized mastoid is highly associated with a deep and posteriorly positioned ST with respect to the facial nerve. The preoperative HRCT scans of patients with cholesteatoma should be carefully evaluated to determine the conformation and depth of the ST.

Computed tomographic findings in 205 dogs with clinical signs compatible with middle ear disease: a retrospective study.

BACKGROUND: Computed tomography (CT) is considered to be the reference method to evaluate middle ear structures. OBJECTIVES: To evaluate the presence and severity of CT changes in the middle ear and establish if any specific clinical presentations are associated with otitis media. ANIMALS: Medical records of animals referred for CT with history and clinical signs consistent with middle ear disease. METHODS: Retrospective evaluation of CT examinations of tympanic bullae performed over a six year period. Medical records were reviewed for signalment, clinical signs and cytological evaluation of the external ear canal. Dogs were divided into three clinical groups: chronic otitis externa (Group 1), peripheral vestibular disorder (Group 2) and other clinical presentations (Group 3). RESULTS: Group 1 - Of 214 ears, 87 (40.7%) had CT abnormalities: 38 of 87 (17.7%) had material-filled bullae, 42 of 87 (19.6%) had thickened bullae walls and seven of 87 (3.2%) had lysis of the bulla. Abnormalities were significantly more frequent in dogs with suppurative otitis than in erythemato-ceruminous otitis (57% and 23%, respectively; P = 0.003). Proliferative otitis, particularly in French bulldogs, was associated with severe otitis media. Group 2 - Of the 106 ears, 91 (85.8%) had normal tympanic bullae. Group 3 - Of the 26 ears from deaf dogs, 17 had filled bullae; all nine affected dogs were Cavalier King Charles spaniels. All dogs with Claude Bernard Horner syndrome or head tilt had normal tympanic bullae. CLINICAL SIGNIFICANCE: CT is useful for canine chronic otitis externa, particularly in suppurative or proliferative otitis, even in the absence of associated neurological signs.

Eustachian tube diameter: Is it associated with chronic otitis media development?

OBJECTIVE: To evaluate the effect of ET diameter on Chronic Otitis Media (COM) pathogenesis. STUDY DESIGN: Retrospective. SUBJECTS AND METHODS: Patients with unilateral COM disease are included in the study. The connection between fibrocartilaginous and osseous segments of the Eustachian Tube (ET) on axial Computed Tomography (CT) images was defined and the diameter of this segment is measured. The measurements were carried out bilaterally and statistically compared. RESULTS: 154 (76 (49%) male, 78 (51%) female patients were diagnosed with unilateral COM and included in the study. The mean diameter of ET was 1947mm (Std. deviation±0.5247) for healthy ears and 1788mm (Std. deviation±0.5306) for diseased ears. The statistical analysis showed a significantly narrow ET diameter in diseased ear side (p<0.01). CONCLUSION: The dysfunction or anatomical anomalies of ET are correlated with COM. Measuring of the bony diameter of ET during routine Temporal CT examination is recommended for our colleagues.

Transtympanic pseudoaneurysm of the internal carotid artery complicating a myringotomy in a four-year old child: Case report and literature review.

We report the first case of a transtympanic iatrogenic internal carotid artery (ICA) pseudoaneurysm diagnosed in a 4-year-old child following a myringotomy. An endovascular treatment with a covered-stent was decided; spontaneous thrombosis was found during the therapeutic arteriography, and the procedure was aborted. Otoscopy and computed tomography (CT) scan monitoring showed a prolonged thrombosis and the disappearance of the pseudoaneurysm 18months after the diagnostic arteriography. Based on literature review, endovascular techniques seem to be preferred to the surgical approach for treatment of intrapetrous ICA pseudoaneurysm, however clinical and CT scan monitoring may also be a valid option.

Radiological Imaging of Rare Intracranial Complications Secondary to Otitis Media and Mastoiditis.

Acute otitis media used to cause fatal results because of its intracranial complications before the introduction of potent and effective antibiotics. After the introduction of antibiotics, complications have started to be observed more frequently as a result of chronic otitis media and especially in children. Because clinical findings changed and became indistinct, the diagnosis of otitis and mastoiditis has been made occasionally with imaging findings only after complications occurred. Multidetector computed tomography and magnetic resonance imaging are efficient and sufficient methods in the rapid diagnosis and should be immediately referred methods.

The role of the nasal and paranasal sinus pathologies on the development of chronic otitis media and its subtypes: A computed tomography study.

OBJECTIVE: This objective of this study is to evaluate the presence and the coincidence of common nasal and paranasal sinus pathologies in adults suffering from chronic otitis media (COM) and its subtypes. MATERIALS AND METHODS: The study group comprised 354 ears of 177 patients who underwent tympanoplasty with or without mastoidectomy from January 2013 to February 2015 due to uni/bilateral COM. Chronic suppurative otitis media, intratympanic tympanosclerosis (ITTS), cholesteatoma, and tympanic membrane with retraction pockets constituted subtypes of COM. The control group consisted of 100 ears of 50 adult patients with aural diseases other than middle ear problems. All patients were evaluated for the evidence of mucosal disease on paranasal sinuses, the presence of concha bullosa (CB), and the angle of nasal septal deviation (NSD) and thickness of the medial mucosa of the inferior turbinate were measured by coronal computed tomography images. RESULTS: The incidence and the angle of NSD were found significantly higher in patients with COM (P = 0.028, P = 0.018; respectively). When ears with unilateral and bilateral COM compared in term of sinonasal pathologies, CB was found higher in patients with unilateral COM (P = 0.040). The presence of CB was significantly higher in ITTS when compared to other subtypes (P = 0.028). CONCLUSIONS: Our study suggests that obstructive nasal pathologies such as NSD and CB may play a role in the pathogenesis of especially unilateral COM. However, there was no correlation between COM and inflammatory pathologies such as sinusitis.

Correlation between Preoperative High Resolution Computed Tomography (CT) Findings with Surgical Findings in Chronic Otitis Media (COM) Squamosal Type.

Background The exact role of High resolution computed tomography (HRCT) temporal bone in preoperative assessment of Chronic suppurative otitis media atticoantral disease still remains controversial. Objective To evaluate the role of high resolution computed tomography temporal bone in Chronic suppurative otitis media atticoantral disease and to compare preoperative computed tomographic findings with intra-operative findings. Method Prospective, analytical study conducted among 65 patients with chronic suppurative otitis media atticoantral disease in Department of Radiodiagnosis, Kathmandu University Dhulikhel Hospital between January 2015 to July 2016. The operative findings were compared with results of imaging. The parameters of comparison were erosion of ossicles, scutum, facial canal, lateral semicircular canal, sigmoid and tegmen plate along with extension of disease to sinus tympani and facial recess. Sensitivity, specificity, negative predictive value, positive predictive values were calculated. Result High resolution computed tomography temporal bone offered sensitivity (Se) and specificity (Sp) of 100% for visualization of sigmoid and tegmen plate erosion. The performance of HRCT in detecting malleus (Se=100%, Sp=95.23%), incus (Se=100%,Sp=80.48%) and stapes (Se=96.55%, Sp=71.42%) erosion was excellent. It offered precise information about facial canal erosion (Se=100%, Sp=75%), scutum erosion (Se=100%, Sp=96.87%) and extension of disease to facial recess and sinus tympani (Se=83.33%,Sp=100%). high resolution computed tomography showed specificity of 100% for lateral semicircular canal erosion (Sp=100%) but with low sensitivity (Se=53.84%). Conclusion The findings of high resolution computed tomography and intra-operative findings were well comparable except for lateral semicircular canal erosion. high resolution computed tomography temporal bone acts as a road map for surgeon to identify the extent of disease, plan for appropriate procedure that is required and prepare for potential complications that can be encountered during surgery.