High-Resolution Computed Tomography of the Inner Ear: Effect of Otosclerosis on Cochlear Aqueduct Dimensions

Objectives: The cochlear aqueduct is a bony duct connecting the scala tympani with the subarachnoid space. Given the pathophysiology of otosclerosis, including bone resorption and new bone deposition, we hypothesize that the cochlear aqueduct in otosclerotic ears is narrowed. Methods: A retrospective review of patients with otosclerosis who have undergone high-resolution computed tomography (HRCT) of the temporal bone was completed. The control cohort included 20 patients with the diagnosis of noise-induced hearing loss, without the diagnosis of otosclerosis. Uniform measurements of cochlear aqueduct dimensions were performed using the axial plane. Results: The otosclerosis cohort included 25 males and 52 females with mean age of 52.2 ± 17.6 years. The control group included 10 males and 10 females with mean age of 64.0 ± 18.5 years. The mean cochlear aqueduct length, width mid canal, aperture base, aperture widest diameter, and funnel diameter in millimeters were 12.19 ± 1.66, 0.68 ± 0.28, 4.21 ± 1.67, 3.23 ± 1.47, and 2.70 ± 1.05 in the ears with otosclerotic foci and 11.57 ± 1.66, 0.69 ± 0.29, 2.56 ± 1.59, 2.77 ± 1.67, and 2.58 ± 1.03 in control group, respectively. Statistical difference was seen in length of cochlear aqueduct, aperture base, and aperture widest diameters ( P = .017, <.001, .007). Conclusions: The length of the cochlear aqueduct and the funnel width are statistically longer in the otosclerotic population compared to control. The width of the cochlear aqueduct is not statistically different.

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Radiographic Measurement of Cochlear in Sudanese Population using High Resolution Computed Tomography (HRCT)

Pertanika Journal of Science and Technology ◽

10.47836/pjst.29.2.32 ◽

2021 ◽

Vol 29 (2) ◽

Author(s):

Lubna Bushara ◽

Mohamed Yousef ◽

Ikhlas Abdelaziz ◽

Mogahid Zidan ◽

Dalia Bilal ◽

...

Keyword(s):

Computed Tomography ◽

Hearing Loss ◽

High Resolution ◽

Temporal Bone ◽

Healthy Subjects ◽

Cochlear Nerve ◽

High Resolution Computed Tomography ◽

Mean Width ◽

The Mean ◽

The Right

This study aimed to determine the measurements of the cochlea among healthy subjects and hearing deafness subjects using a High Resolution Computed Tomography (HRCT). A total of 230 temporal bone HRCT cases were retrospectively investigated in the period spanning from 2011 to 2015. Three 64-slice units were used to examine patients with clinical complaints of hearing loss conditions at three Radiology departments in Khartoum, Sudan. For the control group (A) healthy subjects, the mean width of the right and left cochlear were 5.61±0.40 mm and 5.56±0.58 mm, the height were 3.56±0.36 mm and 3.54±0.36 mm, the basal turn width were 1.87±0.19 mm and 1.88 ±0.18 mm, the width of the cochlear nerve canal were 2.02±1.23 and 1.93±0.20, cochlear nerve density was 279.41±159.02 and 306.84±336.9 HU respectively. However, for the experimental group (B), the mean width of the right and left cochlear width were 5.38±0.46 mm and 5.34±0.30 mm, the height were 3.53±0.25 mm and 3.49±0.28mm, the basal turn width were 1.76±0.13 mm, and 1.79±0.13 mm, the width of the cochlear nerve canal were 1.75±0.18mm and 1.73±0.18mm, and cochlear nerve density were 232.84±316.82 and 196.58±230.05 HU, respectively. The study found there was a significant difference in cochlea’s measurement between the two groups with a p-value < 0.05. This study had established baseline measurements for the cochlear for the healthy Sudanese population. Furthermore, it found that HRCT of the temporal bone was the best for investigation of the cochlear and could provide a guide for the clinicians to manage congenital hearing loss.

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S162 – Chronic Aspiration after Supracricoid Partial Laryngectomy

Otolaryngology ◽

10.1016/j.otohns.2008.05.336 ◽

2008 ◽

Vol 139 (2_suppl) ◽

pp. P130-P131

Author(s):

Andrea Gallo ◽

Giovanni Ruoppolo ◽

Marco Di Mario ◽

Calcagno Paola ◽

Manciocco Valentina ◽

...

Keyword(s):

Computed Tomography ◽

High Resolution ◽

Case Series ◽

Control Group ◽

Chronic Obstructive ◽

Partial Laryngectomy ◽

High Resolution Computed Tomography ◽

Obstructive Pulmonary Disease ◽

Supracricoid Partial Laryngectomy ◽

Control Evaluation

Objectives The aim of this study is to evaluate the long-term swallowing status and the high resolution computed tomography (HRCT) pulmonary findings of chronic aspiration in patients who have undergone supracricoid partial laryngectomy (SCPL), to demonstrate that SCPL causes a mild and well-tolerated degree of chronic aspiration, allowing the patient to avoid a nothing-by-mouth status. Methods Retrospective medical record review. Cohort study. Case series. The follow-up period ranged from 3 to 13 years. 116 patients treated with SCPL were analyzed. The patients included in the study were NED, were followed for more than 3 years, were without tracheal cannula or nasogastric tube, and able to feed orally. A group of 20 patients with chronic obstructive pulmonary disease and normal deglutition was used as a control. Evaluation of postoperative swallowing disorders included a careful observation of the patients by the physician, fiberoptic endoscopic evaluation of swallowing (FEES), and videofluoroscopy (VFS). Clinical grading of postoperative aspiration was assessed according to the Leipzig and Pearson scale. The radiological manifestations of chronic aspiration were recorded at high resolution computed tomography (HRCT). Results A higher incidence of pulmonary consolidation was found in the patients affected by postoperative chronic aspiration, compared to the control group (p<0.001). No significant differences were noted between the control group and the dysphagic group regarding the remaining radiological findings. Conclusions SCPL causes a mild and well-tolerated degree of chronic aspiration, determining low functional impairment and allows the patient a good quality of life.

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Anatomy of the Transarcuate Approach to the Petrous Apex

Otolaryngology ◽

10.1016/j.otohns.2008.05.516 ◽

2008 ◽

Vol 139 (2_suppl) ◽

pp. P98-P98

Author(s):

Alice D Lee ◽

Sanaz Hamidi ◽

Hamid R Djalilian

Keyword(s):

Computed Tomography ◽

High Resolution ◽

Semicircular Canal ◽

Petrous Apex ◽

Minimal Risk ◽

High Resolution Computed Tomography ◽

Superior Semicircular Canal ◽

The Mean ◽

Temporal Bones ◽

Anterior Posterior

Problem The petrous apex is considered to be one of the most difficult areas of the temporal bone to approach surgically. We present data describing the dimensions of a transarcuate approach to the petrous apex, as measured on high resolution computed tomography. Methods Measurements of the mean dimensions and ranges through the crura of the superior semicircular canal were made. The measurements were obtained from high-resolution computed tomography images of 30 temporal bones in 19 consecutively presenting patients with a pneumatized posterior petrous apex cell tract on CT. Measurements were obtained with the use of the standard PACS (picture archiving and communication system) software. Results The mean anterior-posterior space in the superior semicircular canals without transcrural pneumatization was 4.96±0.39 mm. The mean superior- inferior dimension was 4.98±0.48 mm. The same measurements in canals with pneumatized intercrural tracts were 5.17±0.51 mm and 5.11±0.62 mm respectively. The mean anterior-posterior distance and superior-inferior distance of the intercrural air tracts themselves were 2.09±0.57 and 2.01±0.45mm. There was a statistically significant difference in the anterior-posterior size between the pneumatized and non-pneumatized canals but not in the superior-inferior distance. Conclusion Pneumatized bones demonstrate a slight increase in the subarcuate dimensions as compared to non-pneumatized bones. The transarcuate approach is a viable one for drainage and biopsy of the petrous apex. Significance Our study demonstrates that the transarcuate approach is anatomically possible for drainage of the petrous apex with minimal risk to the superior semicircular canal. This would be especially useful for the drainage of cholesterol granulomas of the petrous apex or biopsy in this area.

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Reader accuracy and confidence in diagnosing diffuse lung disease on high-resolution computed tomography of the lungs: impact of sampling frequency

Acta Radiologica ◽

10.1080/02841850802227147 ◽

2008 ◽

Vol 49 (8) ◽

pp. 870-875 ◽

Cited By ~ 4

Author(s):

B. Sundaram ◽

B. H. Gross ◽

E. Oh ◽

N. Müller ◽

J. D. Myles ◽

...

Keyword(s):

Computed Tomography ◽

High Resolution ◽

Lung Disease ◽

Sampling Frequency ◽

High Resolution Computed Tomography ◽

Diffuse Lung Disease ◽

First Choice ◽

The Mean ◽

The Impact ◽

Diffuse Lung

Background: The accuracy of the number of high-resolution computed tomography (HRCT) images necessary to diagnose diffuse lung disease (DLD) is not well established. Purpose: To evaluate the impact of HRCT sampling frequency on reader confidence and accuracy for diagnosing DLD. Material and Methods: HRCT images of 100 consecutive patients with proven DLD were reviewed. They were: 48 usual interstitial pneumonia, 22 sarcoidosis, six hypersensitivity pneumonitis, five each of desquamative interstitial pneumonitis, eosinophilic granulomatosis, and lymphangioleiomyomatosis, and nine others. Inspiratory images at 1-cm increments throughout the lungs and three specified levels formed complete and limited examinations. In random order, three experts (readers 1, 2, and 3) ranked their top three diagnoses and rated confidence for their top diagnosis, independently and blinded to clinical information. Results: Using the complete versus limited examinations for correct first-choice diagnosis, accuracy for reader 1 (R1) was 81% versus 80%, respectively, for reader 2 (R2) 70% versus 70%, and for reader 3 (R3) 64% versus 59%. Reader accuracy within their top three choices for complete versus limited examinations was: R1 91% versus 91% of cases, respectively, R2 84% versus 83%, and R3 79% versus 72% of cases. No statistically significant differences were found between the diagnosis methods ( P=0.28 for first diagnosis and P=0.17 for top three choices). The confidence intervals for individual raters showed considerable overlap, and the point estimates are almost identical. The mean interreader agreement for complete versus limited HRCT for both top and top three diagnoses were the same (moderate and fair, respectively). The mean intrareader agreement between complete and limited HRCT for top and top three diagnoses were substantial and moderate, respectively. Conclusion: Overall reader accuracy and confidence in diagnosis did not significantly differ when fewer or more HRCT images were used.

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An Anatomical Study of the Cochlea among Filipinos using High-Resolution Computed Tomography Scans

Philippine Journal of Otolaryngology Head and Neck Surgery ◽

10.32412/pjohns.v26i1.591 ◽

2011 ◽

Vol 26 (1) ◽

pp. 6-9 ◽

Cited By ~ 2

Author(s):

Adrian F. Fernando ◽

Brian Joseph dG. De Jesus ◽

Alejandro P. Opulencia ◽

Gil M. Maglalang ◽

Antoio H. Chua

Keyword(s):

Computed Tomography ◽

High Resolution ◽

Average Length ◽

Age Groups ◽

Oval Window ◽

University Hospital ◽

High Resolution Computed Tomography ◽

Basal Turn ◽

The Mean ◽

The Right

Objective: To describe the cochlear anatomy among Filipinos through high resolution computed tomography (HRCT) imaging. Methods: Design: Retrospective Study Setting: Tertiary Private University Hospital Patients: Cochlear images retrospectively obtained from computed tomography (CT) scans of subjects who underwent cranial, facial, paranasal sinus and temporal bone computed tomography from October 2009 to July 2010 were reconstructed and analyzed. Results: 388 cochlear images were obtained from the scans of 194 subjects (101 males and 93 females, aged 1 to 90 years old, mean = 52 years) and reconstructed for analysis. The mean coiled cochlear height measured 4.36 mm on the right (A.D.) and 4.34 mm on the left (A.S.). Measurement from the oval window to the distal end of the basal turn (equivalent to the horizontal dimension of the cochlea or the mean length of the basal turn) was 7.55 mm A.D. and 7.60 mm A.S. The vertical and horizontal dimensions of right and left cochleas were identical in all subjects (S.D. = 0.35). The right and left cochlear turns were identical in each subject, exhibiting 2 ½ turns in 92.3% of subjects and 2 ¾ turns in 7.7% of subjects.The cochlear dimensions were similar in all subjects, regardless of age. No cochlear ossification or malformation was noted on any CT image. Conclusion: The 7.55 mm mean length of the cochlear basal turn among Filipinos in this study was 1.24 mm shorter than the average length of the basal turn of 8.81 mm reported elsewhere. Further studies of the cochlear dimensions in specific age groups and its correlation to audiometric status are recommended to determine other significant physiologic correlations. Keywords: cochlea, cochlear turn, high-resolution computed tomography (HRCT), magnetic resonance imaging (MRI)

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Anatomical variations of the temporal bone on high-resolution computed tomography imaging: how common are they?

The Journal of Laryngology & Otology ◽

10.1017/s0022215115001115 ◽

2015 ◽

Vol 129 (7) ◽

pp. 634-637 ◽

Cited By ~ 5

Author(s):

V Visvanathan ◽

M S C Morrissey

Keyword(s):

Computed Tomography ◽

High Resolution ◽

Temporal Bone ◽

Anatomical Variations ◽

Jugular Bulb ◽

Computed Tomography Imaging ◽

High Resolution Computed Tomography ◽

Tomography Imaging ◽

Cochlear Aqueduct ◽

Sinus Tympani

AbstractObjectives:This study aimed to evaluate the prevalence of normal variations of temporal bone anatomy on high-resolution computed tomography imaging and report their clinical importance.Methods:A retrospective review was conducted of high-resolution temporal bone computed tomography imaging performed at NHS Greater Glasgow and Clyde over an eight-year period. The presence of five variants was determined. These variants were: a high dehiscent jugular bulb, an anteriorly located sigmoid sinus, a deep sinus tympani, an enlarged cochlear aqueduct and a large internal auditory meatus.Results:A total of 339 temporal bones were examined. The incidences of a high dehiscent jugular bulb, anteriorly located sigmoid sinus, deep sinus tympani, enlarged cochlear aqueduct and an enlarged internal auditory meatus were 2.76 per cent, 2.94 per cent, 5.01 per cent, 0.58 per cent and 1.76 per cent respectively.Conclusion:Anatomical variations of the temporal bone are not uncommon and it is important for the investigating otologist to be aware of such variations prior to undertaking surgery.

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High-resolution computed tomography findings in elderly patients with asthma

Yearbook of Medicine ◽

10.1016/s0084-3873(08)79203-4 ◽

2008 ◽

Vol 2008 ◽

pp. 283-285

Author(s):

S.K. Willsie

Keyword(s):

Computed Tomography ◽

High Resolution ◽

Elderly Patients ◽

High Resolution Computed Tomography

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Computed Tomography-Based Patient-Specific Instrumentation Loses Accuracy with Significant Varus Preoperative Misalignment

The Journal of Knee Surgery ◽

10.1055/s-0040-1716381 ◽

2020 ◽

Author(s):

Vicente Jesús León-Muñoz ◽

Mirian López-López ◽

Alonso José Lisón-Almagro ◽

Francisco Martínez-Martínez ◽

Fernando Santonja-Medina

Keyword(s):

Computed Tomography ◽

Deformity Correction ◽

Patient Specific ◽

Control Group ◽

X Rays ◽

Varus Alignment ◽

Patient Specific Instrumentation ◽

Conventional Instrumentation ◽

The Mean ◽

Valgus Alignment

AbstractPatient-specific instrumentation (PSI) has been introduced to simplify and make total knee arthroplasty (TKA) surgery more precise, effective, and efficient. We performed this study to determine whether the postoperative coronal alignment is related to preoperative deformity when computed tomography (CT)-based PSI is used for TKA surgery, and how the PSI approach compares with deformity correction obtained with conventional instrumentation. We analyzed pre-and post-operative full length standing hip-knee-ankle (HKA) X-rays of the lower limb in both groups using a convention > 180 degrees for valgus alignment and < 180 degrees for varus alignment. For the PSI group, the mean (± SD) pre-operative HKA angle was 172.09 degrees varus (± 6.69 degrees) with a maximum varus alignment of 21.5 degrees (HKA 158.5) and a maximum valgus alignment of 14.0 degrees. The mean post-operative HKA was 179.43 degrees varus (± 2.32 degrees) with a maximum varus alignment of seven degrees and a maximum valgus alignment of six degrees. There has been a weak correlation among the values of the pre- and postoperative HKA angle. The adjusted odds ratio (aOR) of postoperative alignment outside the range of 180 ± 3 degrees was significantly higher with a preoperative varus misalignment of 15 degrees or more (aOR: 4.18; 95% confidence interval: 1.35–12.96; p = 0.013). In the control group (conventional instrumentation), this loss of accuracy occurs with preoperative misalignment of 10 degrees. Preoperative misalignment below 15 degrees appears to present minimal influence on postoperative alignment when a CT-based PSI system is used. The CT-based PSI tends to lose accuracy with preoperative varus misalignment over 15 degrees.

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