Imaging Review of Subscapularis Tendon and Rotator Interval Pathology

As the largest rotator cuff muscle, the subscapularis plays a major role in stabilizing the glenohumeral joint, in conjunction with surrounding rotator cuff structures. Injury to the subscapularis tendon can be isolated, but more commonly is seen in conjunction with supraspinatus tendon pathology. Injury can be associated with biceps pulley instability, superior labral anterior-posterior (SLAP) tears, humeral head subluxation, and anterosuperior and coracoid impingements. The involvement of the rotator interval can lead to what is called “the hidden lesion,” due to its difficulty to diagnose during arthroscopy. Understanding the anatomical relations of the subscapularis tendon with the rest of the rotator cuff and rotator interval, as well as common patterns of injury that involve the subscapularis tendon, can aid in proper diagnosis of these injuries leading to prompt surgical repair. This review describes the anatomy of the subscapularis muscle and tendon, and the magnetic resonance imaging (MRI) patterns of subscapularis tendon injury.

Comparative Study of Multiple High-Signal-Intensity Spots on 3D and 2D Magnetic Resonance Sialography for Patients with Sjögren’s Syndrome

We investigated the sensitivities of 2-dimensional (2D) magnetic resonance sialography (MR-S) and unilateral sagittal and axial 3-dimensional (3D) MR-S using a surface coil and their combination in diagnosing patients with Sjögren’s syndrome (SS). We retrospectively analyzed the 3D and 2D MR-S results of 78 patients with SS. We evaluated the sensitivities of multiple high-signal-intensity spots and staging on MR sialograms and analyzed the efficient imaging methods and cross section for diagnosing patients with SS. The sensitivities of MR-S for detecting abnormal findings (i.e., MR-S stage 1 or higher) were as follows: 65 cases (83.3% [95% confidence interval (CI): 73.2–90.8]) for unilateral sagittal 3D MR-S; 62 cases (79.4% [95% CI: 68.8–87.8]) for axial 3D MR-S; 66 cases (84.6% [95% CI: 74.7–91.8]) for combined unilateral sagittal and axial 3D MR-S; and 32 cases (41.0% [95% CI: 30.0–52.7]) for bilateral sagittal 2D MR-S. The ratio of the abnormal finding of MR-S was tested using the two-tailed Fisher’s exact test. Unilateral sagittal, axial, and combined unilateral sagittal and axial 3D MR-S showed significantly higher sensitivity than bilateral sagittal 2D MR-S, respectively ( P < 0.001). Most cases upstaged by 3D MR-S were those positive (stage 1 or higher) among the stage 0 cases detected by 2D MR-S. Axial 3D MR-S, compared with 2D MR-S, understaged four cases, which was due to the imaging range of the axial 3D MR-S. We concluded that a single unilateral sagittal 3D MR-S was sufficient and axial 3D MR-S was unnecessary for SS staging. T1- and T2-weighted images are essential for investigating the salivary glands in patients with SS. Therefore, we also concluded that bilateral sagittal 3D MR-S of the parotid glands in addition to T1- and T2-weighted imaging is necessary, sufficient, and most efficient for precise MR imaging examination of the salivary glands, including diagnosing SS.

A Review of Doses for Dental Imaging in 2010–2020 and Development of a Web Dose Calculator

Dental imaging is one of the most common types of diagnostic radiological procedures in modern medicine. We introduce a comprehensive table of organ doses received by patients in dental imaging procedures extracted from literature and a new web application to visualize the summarized dose information. We analyzed articles, published after 2010, from PubMed on organ and effective doses delivered by dental imaging procedures, including intraoral radiography, panoramic radiography, and cone-beam computed tomography (CBCT), and summarized doses by dosimetry method, machine model, patient age, and technical parameters. Mean effective doses delivered by intraoral, 1.32 (0.60–2.56) μSv, and panoramic, 17.93 (3.47–75.00) μSv, procedures were found to be about1% and 15% of that delivered by CBCT, 121.09 (17.10–392.20) μSv, respectively. In CBCT imaging, child phantoms received about 29% more effective dose than the adult phantoms received. The effective dose of a large field of view (FOV) (>150 cm2) was about 1.6 times greater than that of a small FOV (<50 cm2). The maximum CBCT effective dose with a large FOV for children, 392.2 μSv, was about 13% of theeffective dose that a person receives on average every year from natural radiation, 3110 μSv. Monte Carlo simulations of representative cases of the three dental imaging procedures were then conducted to estimate and visualize the dose distribution within the head. The user-friendly interactive web application (available at http://dentaldose.org) receives user input, such as the number of intraoral radiographs taken, and displays total organ and effective doses, dose distribution maps, and a comparison with other medical and natural sources of radiation. The web dose calculator provides a practical resource for patients interested in understanding the radiation doses delivered by dental imaging procedures.

Prevalence and Risk Factors of Work-Related Lower Back Pain among Radiographers in the State of Kuwait

Background. Work-related lower back pain (WrLBP) is a global health issue and a rising concern in the State of Kuwait. The prevalence and the risk factors of WrLBP among radiographers are not well documented. Objective. The purpose of the study was to determine the one-year prevalence, characteristics, impact, and physical risk factors of WrLBP among radiographers in the State of Kuwait. Methods. A self-administered questionnaire was distributed to 200 radiographers. The questionnaire collected data on demographics, physical risk factors, and the occurrence of WrLBP in the previous 12 months. Descriptive statistics, frequency calculations, and chi-square analyses were performed. Results. One hundred forty-six radiographers completed and returned the questionnaires with a response rate of 73% (146/200). The one-year prevalence of WrLBP was 16%. The prevalence of WrLBP was not significantly associated with the participants’ demographics. Although WrLBP was significantly associated with work demands, the overall impact of WrLBP on work duties was minimal. Conclusions. The occurrence of WrLBP among radiographers in Kuwait was low, particularly when compared to healthcare providers involved in more patient handling and direct contact. However, various physical risk factors were identified. Further research is needed to investigate the effect of a treatment and prevention program on the prevalence of WrLBP.

Comparison of Phase Estimation Methods for Quantitative Susceptibility Mapping Using a Rotating-Tube Phantom

Quantitative Susceptibility Mapping (QSM) is an MRI tool with the potential to reveal pathological changes from magnetic susceptibility measurements. Before phase data can be used to recover susceptibility ( Δ χ ), the QSM process begins with two steps: data acquisition and phase estimation. We assess the performance of these steps, when applied without user intervention, on several variations of a phantom imaging task. We used a rotating-tube phantom with five tubes ranging from Δ χ = 0.05 ppm to Δ χ = 0.336 ppm. MRI data was acquired at nine angles of rotation for four different pulse sequences. The images were processed by 10 phase estimation algorithms including Laplacian, region-growing, branch-cut, temporal unwrapping, and maximum-likelihood methods, resulting in approximately 90 different combinations of data acquisition and phase estimation methods. We analyzed errors between measured and expected phases using the probability mass function and Cumulative Distribution Function. Repeatable acquisition and estimation methods were identified based on the probability of relative phase errors. For single-echo GRE and segmented EPI sequences, a region-growing method was most reliable with Pr (relative error <0.1) = 0.95 and 0.90, respectively. For multiecho sequences, a maximum-likelihood method was most reliable with Pr (relative error <0.1) = 0.97. The most repeatable multiecho methods outperformed the most repeatable single-echo methods. We found a wide range of repeatability and reproducibility for off-the-shelf MRI acquisition and phase estimation approaches, and this variability may prevent the techniques from being widely integrated in clinical workflows. The error was dominated in many cases by spatially discontinuous phase unwrapping errors. Any postprocessing applied on erroneous phase estimates, such as QSM’s background field removal and dipole inversion, would suffer from error propagation. Our paradigm identifies methods that yield consistent and accurate phase estimates that would ultimately yield consistent and accurate Δ χ estimates.

Appendiceal Intraluminal Gas: A CT Marker for Gangrenous Appendicitis

Introduction. This manuscript aims to investigate the amount of intraluminal gas in acute, nonperforated appendicitis identified on computed tomography (CT) in diagnosing gangrenous appendicitis. Methods. This is a retrospective observational, case-control study with consecutive data collected at a tertiary institution over a two-year period, of patients with CT-diagnosed acute appendicitis who subsequently went on for surgery within 48 hours. Patients who were less than 16 years old, who had an interval between CT and surgery of more than 48 hours, or with CT evidence of appendiceal perforation were excluded. Images were independently assessed by 3 radiologists for intraluminal gas, and the results were then correlated with reference standards obtained from surgical and histopathology reports for the diagnosis of nongangrenous versus gangrenous appendicitis. The sensitivity, specificity, and predictive values of CT intraluminal gas in gangrenous appendicitis were calculated. Results. Our study identified 93 patients with nonperforated acute appendicitis who underwent surgery within the stated timeframe. Intraluminal gas in the appendix was identified in 26 patients (28%), of which 54% had macroscopic and/or microscopic evidence of gangrenous appendicitis. This is in contrast to the subgroup of patients who did not have intraluminal gas (72%), of which only 33% had gangrenous appendicitis. The specificity of intraluminal gas for gangrenous appendicitis is 79%, with a negative predictive value of 86% and likelihood ratio of 1.85. Conclusion. In cases of established acute appendicitis, the presence of intraluminal gas is a moderately specific sign for gangrenous complication. This is worth reporting as it can help prognosticate and triage patients accordingly, for a timelier surgical management and a better outcome.

Occurrence of the Elongated Styloid Process on Digital Panoramic Radiographs in the Riyadh Population

Background. Patients with an elongated styloid process might present with dysphagia and pain in the cervicofacial region. These patients could be misdiagnosed as other orofacial pathologies. Aim. The present study attempted to assess the prevalence of the elongated styloid process on digital panoramic radiographs in the Riyadh population. Materials and Methods. The present prospective randomized study was conducted on the panoramic digital radiographs of 300 randomly selected patients visiting a private dental hospital to identify any elongation of the styloid process. Only the radiographs without any magnification errors were considered. The styloid process length was measured using the Sidexis measuring tool and entered in an Excel spreadsheet with other demographic data. A length beyond 30 mm was considered styloid process elongation. The data were subjected to statistical analysis. Results. The symptoms of styloid process elongation were higher among females (78.6%), and this difference was statistically significant (χ2 = 7.182; P = 0.007 ). No statistically significant association was observed between styloid process elongation and symptoms between different age groups. Females exhibited a significant longer mean length of the styloid process than males. The present study exhibited a 27.3% prevalence for the elongation and calcification of the styloid process. Conclusion. Given the significant prevalence of the elongated styloid process in our study, we recommend it to be considered as one of the differential diagnosis for pain or discomfort in the orofacial region.

Size of the Carotid Body in Patients with Cardiovascular and Respiratory Diseases Measured by Computed Tomography Angiography: A Case-Control Study

Objectives. Carotid bodies (CBs) play an important role in regulating sympathetic nervous system activity. Thus, they are likely to be enlarged in patients with certain cardiovascular and respiratory diseases. The aim of this case-control study was to verify this hypothesis using computed tomography angiography (CTA). Methods. We retrospectively analysed 141 CTAs including 16 controls, 96 patients with only hypertension (HT), 12 with HT and previous acute myocardial infarction (AMI), 9 with HT and heart failure (HF), and 8 with HT and chronic obstructive pulmonary disease (COPD). We assessed the data using analysis of variance, with p < 0.05 indicating significance. Results. CB average areas in the controls were 2.31 mm2 (right side (RS)) vs. 2.34 mm2 (left side (LS)). CB size was significantly enlarged in patients with HT: 3.07 mm2 (RS) ( p = 0.019 ) vs. 2.91 mm2 (LS) ( p = 0.002 ). If AMI (RS: 3.5 mm2; LS: 3.44 mm2) or HF (RS: 4.01 mm2; LS: 4.55 mm2) was associated with HT, the CB size was even more enlarged. COPD did not affect CB size (RS: 2.40 mm2; LS: 2.29 mm2). Conclusions. Our data showed that certain diseases with increased activity of the sympathetic nervous system were associated with significantly enlarged CBs.

Diagnostic Accuracy Studies in Radiology: How to Recognize and Address Potential Sources of Bias

Accuracy is an important parameter of a diagnostic test. Studies that attempt to determine a test’s accuracy can suffer from various forms of bias. As radiology is a diagnostic specialty, many radiologists may design a diagnostic accuracy study or review one to understand how it may apply to their practice. Radiologists also frequently serve as consultants to other physicians regarding the selection of the most appropriate diagnostic exams. In these roles, understanding how to critically appraise the literature is important for all radiologists. The purpose of this review is to provide a framework for evaluating potential sources of study design biases that are found in diagnostic accuracy studies and to explain their impact on sensitivity and specificity estimates. To help the reader understand these biases, we also present examples from the radiology literature.

Preprocedural Hypertension Is Not a Risk Factor for Postoperative Bleeding following Image-Guided Core Needle Breast Biopsy

Objective. To evaluate the association between preprocedural hypertension and the risk of prolonged bleeding following image-guided core needle breast biopsy in nonpregnant/nonlactating women. Methods. A single institution-based, retrospective cohort study of 400 women who underwent image-guided core needle breast biopsy was conducted. Males and pregnant and lactating women were excluded. Preprocedural systolic or diastolic blood pressure greater than 140 or 90 mm of Hg, respectively, was defined as hypertension. Prolonged bleeding was defined >15 minutes of local, manual pressure required to achieve hemostasis following the biopsy. Severe bleeding complications defined as clinical significant hematoma formation, prolonged bleeding requiring an ER visit, hospitalization, or surgical intervention were also recorded. Results. The difference in the mean time for which manual pressure was held after biopsy for patients with and without preprocedural hypertension was not statistically significant (13 ± 7 vs. 13 ± 8 minutes, respectively, P = 0.856). There was no difference in the number of patients requiring manual postoperative pressure >15 minutes between those with preprocedural hypertension and the normotensive patients (13% vs. 12%, respectively, P = 0.765). Bivariate analysis demonstrated statistically significant association between prolonged bleeding and current antithrombotic or antiplatelet medication use ( P = 0.010), the use of stereotactic guidance ( P = 0.019), and a tethered vacuum-assisted device ( P = 0.045). The use of a tethered vacuum-assisted biopsy device was the only variable associated with prolonged bleeding in the multivariate model ( P = 0.044). Conclusion. Preprocedural hypertension is not a risk factor for prolonged bleeding following image-guided core needle breast biopsies in nonpregnant/nonlactating women.