MRI anatomy and pathology of the anal canal.

The normal function of the anal sphincter complex is crucial for quality of life, as it is the mechanism by which fecal continence is maintained. Additionally, the anal sphincter complex is an integral part of the coordinated effort of defecation. As imaging plays an important role in assessment of pathologic conditions involving the anal region, understanding the normal anatomy of the anal sphincter complex is important for correct image interpretation and accurate diagnosis. This review discusses the anatomy and function of the anal sphincter complex, important technical considerations for MRI, and various inflammatory, infectious, and neoplastic processes, as well as pathologic structural conditions that affect the anal region. Level of Evidence: 5 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2019;50:1018-1032.

Radiologist, obstetric patient, and emergency department provider survey: radiologist-patient interaction in the emergency department setting.

The aim of this study was to evaluate the feasibility and acceptance of a model of direct interaction between radiologist and patients in the emergency department (ED) setting. The study population was comprised of pregnant patients accrued in a non-consecutive prospective manner from June 2014 to September 2015, who had an obstetrical ultrasound performed in the radiology department of an inner-city tertiary care hospital at the request of the ED. The feasibility and approval of direct communication between radiologist and patient were evaluated by means of a questionnaire presented by an independent observer to the ED provider, patient, and radiologist. The exam enrolled 54 patients. Ultrasound (US) exam results were divided into (31) normal live intrauterine gestation (group 1), (7) abnormal failed intrauterine gestation or ectopic pregnancy (group 2), and (16) indeterminate pregnancies that could not be placed in the former categories and may require a follow-up exam (group 3). Forty-five (83 %) ED providers approved of the radiologist's direct communication with patients. Fifty (93 %) patients stated a better understanding of the radiologist's role in their care after than before the interaction. The radiologists found the interaction with patients to be positive in 52 (96 %) cases. Direct communication between radiologist and patient yielded a good acceptance by the radiologist, ED provider, and patient. More importantly, after the encounter, the vast majority of patients reported a better understanding of the radiologist's role in their care.

Diagnostic significance of the CT rim sign in cases of gangrenous cholecystitis.

PURPOSE: To evaluate the association between the CT rim sign and gangrenous cholecystitis (GC) and increased surgical difficulty. METHOD: Patients who had a contrast enhanced CT of the abdomen and pelvis, followed by non-elective cholecystectomy were analyzed. The scans were reviewed for the CT rim sign by radiologists blinded to the pathologic and clinical outcomes. Demographic and clinical characteristics were compared between patients with and without GC using t-tests or Wilcoxon ranked sum test for continuous variables, and Fishers' exact test for categorical variables, when appropriate. A logistic regression model was fitted with multiple risk factors. Odds ratios as well as 95% confidence intervals were then calculated for the risk factors. A secondary analysis predicting increased surgical difficulty, defined as an operative time of greater than 2 h or increased conversion rate to open surgery, was also examined. RESULTS: A total of 100 patients were included; 20 of which had GC. On imaging, patients with GC were more likely to have a CT rim sign (65% vs 32.5%, OR = 3.80, 95% CI: 1.24-12.7, p = 0.011). The presence of the CT rim sign did not reach a statistically significant association with an operative time >2 h or conversion to open case (56.52% vs 33.77%, OR = 2.55, p = 0.056). CONCLUSION: The CT rim sign can be utilized to raise the possibility of GC, however the presence of the CT rim sign does not demonstrate an association with increased surgical difficulty.

Association between linear skull fractures and intracranial hemorrhage in children with minor head trauma.

BACKGROUND: To determine whether skull fractures can be used to associate intracranial hemorrhage with minor head trauma (MHT). OBJECTIVE: We conducted a retrospective study evaluating the association between linear skull fractures and intracranial hemorrhage among children with MHT. Furthermore, we evaluated the significance of small intracranial hemorrhages by assessing the need for neurosurgical interventions. MATERIALS AND METHODS: The case group included 114 children with a diagnosis of a linear skull fracture and the control group included 125 children without the diagnosis. We conducted multivariable logistic regression analyses to estimate the odds ratio (OR) between linear skull fractures and intracranial bleeding. RESULTS: Among the cases, 29 of 114 (25%) children were diagnosed with an intracranial hemorrhage on CT, compared to only 14 of 125 (11%) among the controls. The multivariable OR for intracranial hemorrhages comparing cases and controls adjusted for age and gender was 2.17 (95% confidence interval [CI]: 1.01, 4.68). All the intracranial hemorrhages were small (3.8 +/- 2.3 mm) and none of them required any neurosurgical intervention. CONCLUSION: The presence of a linear skull fracture is an independent risk factor for intracranial hemorrhage. However, all the intracranial hemorrhages associated with the skull fractures were small and did not require any neurosurgical interventions.

Contrast enhanced ultrasound: A review of radiology applications.

Ultrasound contrast agents have been used for decades in Europe and Asia for cardiac and abdominal imaging and are now being more commonly utilized in the United States for radiology applications. Our article reviews the basics of contrast-enhanced ultrasound including how the contrast agent works, advantages and disadvantages, as well as pearls and pitfalls to help the radiologist efficiently integrate this technology into day-to-day clinical practice. We also discuss the diagnosis of focal hepatic lesions as well as off-label applications such as evaluation of renal masses.

Evaluation of suture abrasion against rotator cuff tendon and proximal humerus bone.

PURPOSE: This study evaluates the abrasion properties of different suture materials through the rotator cuff tendon and proximal humerus tuberosity bone. METHODS: Three types of sutures were compared: monofilament polypropylene, braided polyester, and braided polyblend polyester with a polyethylene core. For soft-tissue testing, the suture was passed through the infraspinatus tendons of 11 cadaveric shoulders. The suture was cycled with a fixed load, and the migration of the suture as it cut through the tissue was measured at intervals of 5 cycles, for a total of 50 cycles. For tuberosity testing, the sutures were passed through a transosseous tunnel created in the lesser tuberosity, and the suture was cycled with a fixed load until suture failure occurred. RESULTS: On soft-tissue testing, the monofilament suture showed the least amount of abrasion, followed by the braided polyblend and then the braided polyester suture (cutting rate of 0.06 +/- 0.11 mm/cycle, 0.99 +/- 0.44 mm/cycle, and 1.75 +/- 0.91 mm/cycle, respectively; P < .0001). On tuberosity testing, suture breakage for the braided polyblend suture occurred at 501.3 +/- 220.4 cycles. The braided polyester and monofilament sutures broke after 256.6 +/- 120.9 and 193.5 +/- 144.8 cycles, respectively. The difference between cycles to failure of the polyblend and latter 2 sutures was statistically significant (P < .0001). CONCLUSIONS: This study shows increased abrasion properties for braided sutures compared with monofilament sutures, as well as different abrasion properties among different types of braided sutures. Furthermore, the braided polyblend suture showed significantly increased cycles before suture failure through a transosseous tunnel. CLINICAL RELEVANCE: Although development of new suture materials has increased their failure strength, further advancements in suture material design should focus on decreasing soft-tissue abrasion properties and increasing strength to suture failure when cycled through bone.

Use of multidetector computed tomography 3D reconstructions in assessing lower tracheal-bronchial pathology and subsequent surgical interventions.

PURPOSE: To evaluate the contribution of 3D reconstruction in assessing lower tracheobronchial pathology and surgical interventions. METHODS: Twenty patients fit our criteria of lower tract tracheobronchial pathologies for a total of 25 abnormalities. Studies were reviewed by two board certified pediatric radiologists. Diagnostic value of 3D reconstruction in assessing surgical findings was evaluated. RESULTS: Three-dimensional (3D) reconstruction was perceived to add specific information in seven cases: three cases clarifying how attempting surgical intervention would be helpful, and in four cases, 3D reconstruction gave added information that aided surgical planning. CONCLUSIONS: Three-dimensional reconstructions can be a helpful tool in planning surgical interventions.