Citations

Background SynthesiZed Improved Resolution and Concurrent nOise reductioN (ZIRCON) is a multi-kernel synthesis method that creates a single series of thin-slice computed tomography (CT) images displaying low noise and high spatial resolution, increasing reader efficiency and minimizing partial volume averaging. Purpose To compare the diagnostic performance of a single set of ZIRCON images to two routine clinical image series using conventional CT head and bone reconstruction kernels for diagnosing intracranial findings and fractures in patients with trauma or suspected acute neurologic deficit. Material and Methods In total, 50 patients underwent clinically indicated head CT in the ER (15 normal, 35 abnormal cases). A non-reader neuroradiologist established the reference standard. Three neuroradiologists reviewed two routine clinical series (head and bone kernels) and a single ZIRCON series, detecting intracranial findings or fractures and rating confidence (0–100). Sensitivity, specificity, and jackknife free-response receiver operating characteristic (JAFROC) figure of merit (FOM) were compared (limit of non-inferiority: −0.10). Results ZIRCON and conventional images demonstrated comparable performance for fractures (sensitivity: 51.5% vs. 54.5%; specificity: 40.2% vs. 34.2%) and intracranial findings (sensitivity: 88.2% vs. 91.4%; specificity: 77.2% vs. 73.7%).The estimated difference of JAFROC FOM demonstrated ZIRCON non-inferiority for acute pathologies overall (0.003 [95% CI=−0.051–0.057]) and fractures (0.048 [95% CI=−0.050–0.145]) but not for intracranial findings alone (−0.024 [95% CI=−0.100–0.052]). Conclusion Thin-slice, low noise, and high spatial resolution images can be created to display intracranial findings and fractures replacing multiple images series in head CT with similar performance. Future studies in more patients and further algorithmic development are warranted.

Background Recently, genetic testing for sarcomeric hypertrophic cardiomyopathy (HCM) became a commercially available diagnostic test involving analysis of 8 HCM-associated myofilament genes, four of which encode thin filament proteins - TNNT2- encoded cardiac troponin T, TPM1 -encoded alpha tropomyosin, TNNI3- encoded cardiac troponin I, and ACTC- encoded cardiac actin. Compared to the two most common subtypes of sarcomeric HCM, much less is known about the prevalence and spectrum of thin filament HCM. Methods Comprehensive open reading frame/splice site mutational analysis of these 4 thin filament-encoding genes was performed, using polymerase chain reaction, denaturing high performance liquid chromatography, and direct DNA sequencing, on the largest assembled cohort of unrelated patients (N = 1025, 61% male, 49 ± 18 years at diagnosis, maximal left ventricular wall thickness, LVWT, 22.3 ± 7 mm) with clinically diagnosed HCM that were seen at the Mayo Clinic. Results Nineteen distinct missense mutations, involving conserved residues and absent in 600 reference alleles, were identified in 36 of 1025 patients (3.5%) including TNNT2 (16 patients), TNNI3 (12), TPM1 (7) and ACTC (1). Among these 36 patients with thin filament-HCM, their average age at diagnosis was 33.2 ± 16 years and the average LVWT was 21 ± 8 mm. Eighteen patients (50%) had evidence for familial HCM and 13% had a positive history for sudden cardiac death. Only 13 patients (36%) had a reverse septal curvature by echocardiography. Instead, 12 patients (34%) had either sigmoidal or neutral septal contours and 9 patients (25%) had apical variant-HCM. Conclusion Here, we present the largest cohort analysis of thin filament HCM to date and detail the prevalence and spectrum of HCM-associated mutations in these 4 genes. Compared to the strong association between reverse septal curvature and thick filament HCM, the septal morphology associated with thin filament HCM was quite varied. Contrary to published estimates of the frequency of troponin T-HCM (5 – 10%) and the other subtypes of thin filament HCM, the prevalence of thin filament HCM was very low in this cohort. If confirmed in other cohorts, a revised cascade for HCM genetic testing should be considered.

Abstract Background & Aims The epidemiology of hepatitis B virus (HBV) infection differs between Asians and non‐Asians, but little is known regarding the effect of ethnicity on outcomes of HBV‐related hepatocellular carcinoma (HCC). We aim to characterize the presentation and survival outcomes in Asian and non‐Asian patients with HBV‐related HCC. Methods We analyzed the baseline characteristics and long‐term survival of 613 Asian and 410 non‐Asian patients with HBV‐related HCC from three US and one Spanish centre. Results Overall, non‐Asian patients were more likely to have HIV or hepatitis C co‐infection, cirrhosis, decompensated liver disease and advanced BCLC stage (all P ≤ .04). Compared with Asians, non‐Asians were more likely to be listed for transplantation ( P < .0001) and undergo HCC treatment with curative intent ( P = .003). Propensity‐score matching on HCC diagnosis year, gender and age was performed to balance the two groups for survival analysis and yielded 370 pairs of patients. There was no significant difference in survival overall ( P = .43) and among patients with cirrhosis ( P = .57). Among patients without cirrhosis, non‐Asians had poorer 5‐year survival compared with Asians (37.6% vs 53.7%, P = .01), and was associated with poorer survival after adjusting for age, gender, diabetes, alcohol, co‐infections, diagnosis date, antiviral therapy, BCLC stage and HCC treatment (adjusted HR 2.01 [95% CI 1.07‐3.74], P = .03). Conclusion Among HBV‐related HCC patients, non‐Asians presented with more advanced BCLC stage compared to Asians. Non‐Asian ethnicity was independently associated with twice the risk of mortality among patients without cirrhosis, but not among those with cirrhosis. Additional studies are needed to clarify this disparity.

A system has been developed for the identification of aerobic actinomycetes in the clinical laboratory based on analysis of whole cells for diaminopimelic acid and carbohydrates and on the ability of the organism to decompose casein, tyrosine, and xanthine media. The whole-cell analyses were performed by a simple thin-layer chromatographic procedure that is described. Eighteen reference cultures were correctly identified and, subsequently, 35 isolates from clinical material were grouped by using this system. The method is well suited for use in routine clinical laboratories.

BackgroundFusion of diffusion‐weighted imaging (DWI) to computed tomography (CT) has been touted as a possible technique to improve cholesteatomas localization. This study set out to assess the ability of DWI images fused with thin‐slice heavily T2‐weighted images to similarly localize surgically‐confirmed cholesteatomas.Materials and MethodsA retrospective review was completed of consecutive patients that underwent MR temporal bone imaging (9/2011–3/2020) with both DWI and thin‐slice T2‐weighted imaging. Included patients underwent surgical resection of primary or recidivistic cholesteatoma after preoperative MR imaging. A neuroradiologist, who was blinded to operative and clinical notes, localized each lesion on both DWI and fused DWI‐T2 images in 11 anatomic subdivisions of the temporal bone. Surgical confirmation of cholesteatoma location was used as the gold standard for comparison.ResultsOf 24 included examinations, the average age at time of MR was 48.2 ± 24.7 years; 12/24 (50.0%) were female. Five of 24 had primary cholesteatoma, while the remainder had recidivistic disease. Sensitivity, specificity, and accuracy of unfused DWI images were 52.1%, 88.9%, and 75.8%, respectively. Sensitivity, specificity, and accuracy of fused DWI‐T2 images were 57.1%, 94.8%, and 81.8%, respectively.ConclusionFused DWI‐T2 images outperformed unfused DWI images in the anatomic localization of temporal bone cholesteatomas. This method represents a potential alternative to MR‐CT fusion for pre‐operative cholesteatoma evaluation, and warrants future investigations. Opposed to MR‐CT fusion, this method only necessitates MR sequences and removes the need for additional CT acquisition.Level of Evidence3 Laryngoscope, 131:E1662–E1667, 2021

Abstract Thin-film microelectrode arrays have a wide variety of applications in research and medical devices. Conventionally, these arrays are fabricated through the use of photolithography, which can be problematic for innovative medical device fabrication due to long process times, inflexibility to design changes, and the reliance on potentially harmful chemicals. Here, we present the use of laser micromachining as an alternative to photolithography processes to fabricate thin-film polyimide microelectrode arrays. This fabrication method lends itself to an iterative design process as it can reduce fabrication steps and is attractive for medical devices since it can be used without harmful chemicals. Several process parameters were explored and the performance of the fabricated electrodes was compared to similar electrodes that were fabricated with conventional photolithography processes.