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1.
Cureus ; 15(7): e41606, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37559836

ABSTRACT

We present the case of a 35-year-old patient who presented with a three-month history of left-sided sensorineural hearing loss and left-sided facial weakness. Initial imaging suggested a schwannoma, and the patient underwent ten treatments of intra-tympanic steroid injections and antibiotics, and was scheduled for surgery. However, the planned schwannoma removal surgery with gamma-knife was aborted due to the absence of the previously identified mass on the pre-procedure MRI. Subsequent imaging revealed continued enhancement of the left internal auditory canal (IAC), leading to considerations of lymphoma, sarcoidosis, IgG4 disease, or other inflammatory condition. The patient's symptoms have significantly improved since and are currently being conservatively managed and monitored. However, the patient continues to show persistent findings on MRI. This case highlights the diagnostic challenges faced in identifying the underlying etiology of this patient and emphasizes the need for further investigations and multidisciplinary management in patients with similar presentations.

2.
Cureus ; 15(8): e44215, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37641727

ABSTRACT

The implementation of artificial intelligence (AI) in radiology has shown significant promise in the identification of acute intracranial hemorrhages (ICHs). However, it is crucial to recognize that AI systems may produce false-positive results, especially in the postoperative period. Here, we present two cases where AI prioritization software erroneously identified an acute ICH on a postoperative non-contrast CT. These cases highlight the need for a more careful radiology review of AI-flagged images in postoperative patients to avoid further unnecessary imaging and unwarranted concerns from radiologists, clinicians, and patients.

3.
Eur J Radiol ; 164: 110865, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37167684

ABSTRACT

PURPOSE: The Prostate Imaging Quality (PI-QUAL) score is a metric to evaluate the diagnostic quality of multiparametric magnetic resonance imaging (MRI) of the prostate. This study evaluated the impact of a prostate MRI quality training lecture on the participant's ability to assess prostate MRI image quality. METHODS: Eighteen in-training-radiologists of varying experience in reviewing diagnostic prostate MRI assessed the image quality of ten examinations. Then, they attended a dedicated lecture on MRI quality assessment using the PI-QUAL score. After the lecture, the same participants evaluated the image quality of a new set of ten scans applying the PI-QUAL score. Results were assessed using receiver operating characteristic (ROC) analysis. The reference standard was the PI-QUAL score assessed by a fellowship trained abdominal radiologist with experience in reading prostate MRI. RESULTS: There was a significant improvement in the average area under the curve (AUC) for assessment of prostate MRI image quality from baseline (0.82; [0.576 - 0.888]) to post teaching (1.0; [0.954-1]), with an improvement of 0.18 (p < 0.03). When ROC curves were computed for different cohorts stratified based on year of training, difference ranged from 0.48 for second year residents to 0.32 for fourth year residents (p < 0.001-0.01). For abdominal imaging fellows, the pre-teaching AUC was 0.9 [0.557-1] and post teaching AUC was 1 [0.957-1], a difference of 0.1 (p = 0.20). CONCLUSIONS: A dedicated lecture on PI-QUAL improved the ability of radiologists-in-training to assess prostate MRI image quality, with variable impact depending on year of training.


Subject(s)
Multiparametric Magnetic Resonance Imaging , Prostatic Neoplasms , Male , Humans , Prostate/diagnostic imaging , Prostate/pathology , Prostatic Neoplasms/pathology , Magnetic Resonance Imaging/methods , Curriculum , Retrospective Studies
4.
Otol Neurotol ; 36(1): 172-7, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25076227

ABSTRACT

HYPOTHESIS: Power reflectance (PR) measurements in ears with superior canal dehiscence (SCD) have a characteristic pattern, the detection of which can assist in diagnosis. BACKGROUND: The aim of this study was to determine whether PR coupled with a novel detection algorithm can perform well as a fast, noninvasive, and easy screening test for SCD. The screening test aimed to determine whether patients with various vestibular and/or auditory symptom(s) should be further considered for more expensive and invasive tests that better define the diagnosis of SCD (and other third-window lesions). METHODS: Power reflectance was measured in patients diagnosed with SCD by high-resolution computed tomography. The study included 40 ears from 32 patients with varying symptoms (e.g., with and without conductive hearing loss, vestibular symptoms, and abnormal auditory sensations). RESULTS: Power reflectance results were compared to previously published norms and showed that SCD is commonly associated with a PR notch near 1 kHz. An analysis algorithm was designed to detect such notches and to quantify their incidence in affected and normal ears. Various notch detection thresholds yielded sensitivities of 80% to 93%, specificities of 69% to 72%, negative predictive values of 84% to 93%, and a positive predictive value of 67%. CONCLUSION: This study shows evidence that PR measurements together with the proposed notch-detecting algorithm can be used to quickly and effectively screen patients for third-window lesions such as SCD in the early stages of a diagnostic workup.


Subject(s)
Algorithms , Diagnostic Techniques, Otological , Labyrinth Diseases/diagnosis , Semicircular Canals/pathology , Adult , Aged , Female , Humans , Male , Middle Aged , Pressure , Tomography, X-Ray Computed
5.
J Acoust Soc Am ; 133(2): 918-37, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23363110

ABSTRACT

Sound-induced motions of the surface of the tympanic membrane (TM) were measured using stroboscopic holography in cadaveric human temporal bones at frequencies between 0.2 and 18 kHz. The results are consistent with the combination of standing-wave-like modal motions and traveling-wave-like motions on the TM surface. The holographic techniques also quantified sound-induced displacements of the umbo of the malleus, as well as volume velocity of the TM. These measurements were combined with sound-pressure measurements near the TM to compute middle-ear input impedance and power reflectance at the TM. The results are generally consistent with other published data. A phenomenological model that behaved qualitatively like the data was used to quantify the relative magnitude and spatial frequencies of the modal and traveling-wave-like displacement components on the TM surface. This model suggests the modal magnitudes are generally larger than those of the putative traveling waves, and the computed wave speeds are much slower than wave speeds predicted by estimates of middle-ear delay. While the data are inconsistent with simple modal displacements of the TM, an alternate model based on the combination of modal motions in a lossy membrane can also explain these measurements without invoking traveling waves.


Subject(s)
Bone Conduction , Holography , Mechanotransduction, Cellular , Models, Biological , Tympanic Membrane/physiology , Acoustic Stimulation , Cadaver , Fourier Analysis , Humans , Motion , Pressure , Sound , Stroboscopy , Time Factors , Tympanic Membrane/anatomy & histology , Vibration
6.
Ear Hear ; 33(1): 35-43, 2012.
Article in English | MEDLINE | ID: mdl-21857516

ABSTRACT

OBJECTIVE: The goal of the present study was to investigate the clinical utility of measurements of ear-canal reflectance (ECR) in a population of patients with conductive hearing loss in the presence of an intact, healthy tympanic membrane and an aerated middle ear. We also sought to compare the diagnostic accuracy of umbo velocity (VU) measurements and measurements of ECR in the same group of patients. DESIGN: This prospective study comprised 31 adult patients with conductive hearing loss, of which 14 had surgically confirmed stapes fixation due to otosclerosis, 6 had surgically confirmed ossicular discontinuity, and 11 had computed tomography and vestibular evoked myogenic potential confirmed superior semicircular canal dehiscence (SCD). Measurements on all 31 ears included pure-tone audiometry for 0.25 to 8 kHz, ECR for 0.2 to 6 kHz using the Mimosa Acoustics HearID system, and VU for 0.3 to 6 kHz using the HLV-1000 laser Doppler vibrometer (Polytec Inc, Waldbronn, Germany). We analyzed power reflectance |ECR| as well as the absorbance level = 10 × log10(1 - |ECR|). All measurements were made before any surgical intervention. The VU and ECR data were plotted against normative data obtained in a companion study of 58 strictly defined normal ears (). RESULTS: Small increases in |ECR| at low-to-mid frequencies (400-1000 Hz) were observed in cases with stapes fixation, while narrowband decreases were seen for both SCD and ossicular discontinuity. The SCD and ossicular discontinuity differed in that the SCD had smaller decreases at mid-frequency (∼1000 Hz), whereas ossicular discontinuity had larger decreases at lower frequencies (500-800 Hz). SCD tended to have less air-bone gap at high frequencies (1-4 kHz) compared with stapes fixation and ossicular discontinuity. The |ECR| measurements, in conjunction with audiometry, could successfully separate 28 of the 31 cases into the three pathologies. By comparison, VU measurements, in conjunction with audiometry, could successfully separate various pathologies in 29 of 31 cases. CONCLUSIONS: The combination of |ECR| with audiometry showed clinical utility in the differential diagnosis of conductive hearing loss in the presence of an intact tympanic membrane and an aerated middle ear and seems to be of similar sensitivity and specificity to measurements of VU plus audiometry. Additional research is needed to expand upon these promising preliminary results.


Subject(s)
Acoustic Impedance Tests/methods , Acoustic Impedance Tests/standards , Ear Canal/physiology , Hearing Loss, Conductive/diagnosis , Tympanic Membrane/physiology , Adult , Aged , Audiometry, Pure-Tone , Female , Hearing Loss, Conductive/pathology , Hearing Loss, Conductive/surgery , Humans , Male , Middle Aged , Pilot Projects , Preoperative Care , Prospective Studies , Reproducibility of Results , Semicircular Canals/pathology , Sensitivity and Specificity , Stapes Mobilization , Young Adult
7.
Ear Hear ; 33(1): 19-34, 2012.
Article in English | MEDLINE | ID: mdl-21857517

ABSTRACT

OBJECTIVE: This study compares measurements of ear-canal reflectance (ECR) to other objective measurements of middle ear function including audiometry, umbo velocity (VU), and tympanometry in a population of strictly defined normal-hearing ears. DESIGN: Data were prospectively gathered from 58 ears of 29 normal-hearing subjects, 16 females and 13 males, aged 22 to 64 yr. Subjects met all of the following criteria to be considered as having normal hearing: (1) no history of significant middle ear disease; (2) no history of otologic surgery; (3) normal tympanic membrane on otoscopy; (4) pure-tone audiometric thresholds of 20 dB HL or better for 0.25 to 8 kHz; (5) air-bone gaps no greater than 15 dB at 0.25 kHz and 10 dB for 0.5 to 4 kHz; (6) normal, type-A peaked tympanograms; and (7) all subjects had two "normal" ears (as defined by these criteria). Measurements included pure-tone audiometry for 0.25 to 8 kHz, standard 226 Hz tympanometry, ECR for 0.2 to 6 kHz at 60 dB SPL using the Mimosa Acoustics HearID system, and umbo velocity (VU) for 0.3 to 6 kHz at 70 to 90 dB SPL using the HLV-1000 laser Doppler vibrometer (Polytec Inc). RESULTS: Mean power reflectance (|ECR|) was near 1.0 at 0.2 to 0.3 kHz, decreased to a broad minimum of 0.3 to 0.4 between 1 and 4 kHz, and then sharply increased to almost 0.8 by 6 kHz. The mean pressure reflectance phase angle (∠ECR) plotted on a linear frequency scale showed a group delay of approximately 0.1 msec for 0.2 to 6 kHz. Small significant differences were observed in |ECR| at the lowest frequencies between right and left ears and between males and females at 4 kHz. |ECR| decreased with age but reached significance only at 1 kHz. Our ECR measurements were generally similar to previous published reports. Highly significant negative correlations were found between |ECR| and VU for frequencies below 1 kHz. Significant correlations were also found between the tympanometrically determined peak total compliance and |ECR| and VU at frequencies below 1 kHz. The results suggest that middle ear compliance contributes significantly to the measured power reflectance and umbo velocity at frequencies below 1 kHz but not at higher frequencies. CONCLUSIONS: This study has established a database of objective measurements of middle ear function (ECR, umbo velocity, tympanometry) in a population of strictly defined normal-hearing ears. These data will promote our understanding of normal middle ear function and will serve as a control for comparison to similar measurements made in pathological ears.


Subject(s)
Acoustic Impedance Tests/standards , Ear Canal/physiology , Ear, Middle/physiology , Hearing/physiology , Acoustic Impedance Tests/methods , Adult , Audiometry, Pure-Tone/methods , Audiometry, Pure-Tone/standards , Calibration/standards , Female , Humans , Male , Middle Aged , Reference Values , Sex Characteristics , Young Adult
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