Longitudinal MR Quantification of the Fat Fraction within the Supraspinatus and Infraspinatus Muscles in Patients with Shoulder Pain.

Rationale And Objectives: Knowing the natural history of fatty degeneration of rotator cuff muscles is important for estimating the risk and rate of progression to cuff tear arthropathy (CTA). The purpose of this study was to investigate the changes in rotator cuff muscle fatty degeneration over time quantitatively in patients treated conservatively for shoulder pain.

Materials And Methods: Thirty patients with a baseline and follow-up shoulder MRI, including a 2-point Dixon sequence, which were performed at least 1 year apart, were included.

Review of Quantitative Knee Articular Cartilage MR Imaging.

Osteoarthritis (OA) is one of the most prevalent disorders in today's society, resulting in significant socio-economic costs and morbidity. MRI is widely used as a non-invasive imaging tool for OA of the knee. However, conventional knee MRI has limitations to detect subtle early cartilage degeneration before morphological changes are visually apparent.

Quantitative MRI Analysis of the Talocrural and Talonavicular Joints in Ballet Dancers.

The ankles of ballet dancers are routinely under heavy loading that may lead to osteoarthritic changes. It would be clinically useful to identify such pathology as early as possible in a dancer's career. Therefore, the purpose of this study was to compare quantitative measurements in magnetic resonance (MR) images of the talocrural and talonavicular joints in ballet dancers and healthy non-dancers for use in formulating prediction of chronic injury and degenerative joint disease in these locations.

Prediction of Stress Distribution Applied to the Triangular Fibrocartilage Complex: A Finite Element Analysis.

Purpose: The triangular fibrocartilage complex (TFCC) is an important tissue stabilizer for the distal radioulnar joint, but stress distribution on the TFCC is not clear. The purpose of this study was to report the stress distribution of the TFCC using finite element analysis (FEA).

Methods: Pathological specimens of the wrist joint from an 80-year-old man were imported into a finite element analysis software package, and regions of interest including bone, soft tissue, and TFCC were extracted to create a 3-dimensional model.

There are no three physiological narrowings in the upper urinary tract: a new concept of the retroperitoneal anatomy around the ureter.

The widely held dogma of three physiological narrowings in the upper urinary tract has proven incorrect by recent several studies using computed tomography images. There are only two common obstruction sites: the upper ureter and the ureterovesical junction. The second narrowing, where the ureter crosses the iliac vessels, cannot be regarded anymore as a common obstruction site.

Comparison of visibility of ulnar sided triangular fibrocartilage complex (TFCC) ligaments between isotropic three-dimensional and two-dimensional high-resolution FSE MR images.

Objectives: Assessment of the ulnar attachment of the triangular fibrocartilage complex (TFCC) in a neutral forearm position remains challenging. Our study aims to evaluate the visibility of ulnar sided TFCC on 3 T MRI and compare isotropic 3D FSE sequences utilizing multiplanar reformation (MPR) with standard high-resolution 2D FSE sequences.

Methods: Ninety-nine MRI wrist studies in patients with wrist pain were retrospectively analyzed.

Anatomical relationship between the morphology of the styloid process of the ulna and the attachment of the radioulnar ligaments.

The radioulnar ligaments are the major stabilizers of the distal radioulnar joint under dynamic loading; however, anatomical detail regarding their attachment on the middle and distal thirds of the styloid process of the ulna remains unclear. Because previous anatomical studies included only old cadavers, their anatomical findings might not reflect the morphological features of younger and healthy specimens. This study investigated the anatomical features of the distal ulna, particularly the styloid process, to determine the attachment of the radioulnar ligaments to the styloid process and verified their direction and attachment to the styloid process in younger and healthy donors using magnetic resonance imaging (MRI).

T1rho and T2 mapping of ankle cartilage of female and male ballet dancers.

Background: Since ballet dancers begin their training before skeletal maturity, accurate and non-invasive identification of cartilage diseases is clinically important. Angle-dependent analysis of T1rho and T2 sequences can be useful for quantification of the composition of cartilage.

Purpose: To investigate the angle-dependent T1rho and T2 profiles of ankle cartilage in non-dancers and dancers.

Extrahepatic Collateral Artery Extravasation in Patients with Ruptured Hepatocellular Carcinoma.

This report describes 3 patients with previously untreated hepatic tumors who underwent embolization for the treatment of extravasation from extrahepatic arteries. Although development of extrahepatic collateral blood supply is well known, its importance in the presentation of rupture of liver tumors may be underrecognized. Findings that suggest bleeding from extrahepatic arteries include a discrepancy in the pattern of extravasation on computed tomography vs hepatic angiography and a lack of stabilization of vital signs after embolization of hepatic arteries.

Comparison Between Isotropic 3-Dimensional Fat-Suppressed T2-Weighted Fast Spin Echo (FSE) and Conventional 2-Dimensional Fat-Suppressed Proton-Weighted FSE Shoulder Magnetic Resonance Imaging at 3-T in Patients With Shoulder Pain.

Objective: The aims of this study were to compare isotropic 3-dimensional fat-suppressed T2-weighted fast spin echo (FSE) imaging (T2FS) with 2-dimensional fat-suppressed proton-density-weighted FSE imaging (2D-PDFS) and evaluate feasibility of isotropic 3-dimensional FSE shoulder imaging at 3-T magnetic resonance imaging (MRI).

Methods: Seventy-eight patients who underwent shoulder MRI were evaluated. Three-dimensional T2FS and 2D-PDFS were qualitatively graded for delineation of anatomic structures.

Mucin-poor and aggressive mucinous tubular and spindle cell carcinoma of the kidney: Two case reports.

Mucinous tubular and spindle cell carcinoma (MTSCC) is a relatively rare renal epithelial neoplasm. Although MTSCC is considered to be a low-grade and indolent neoplasm, aggressive cases have been recently reported. The present study discussed two additional cases of high-grade MTSCC causing multiple distant metastases with a fatal course.

Advanced Imaging Techniques of the Wrist.

Objective: This article covers the technical aspects and clinical applications of recent advancements in wrist MRI techniques, including T2 and T1rho mapping, compressed sensing, and isotropic 3D imaging using driven equilibrium sequences, variable-flip-angle refocusing pulse sequences, and parallel imaging. The clinical applications of these techniques include the quantitative analysis of cartilage and triangular fibrocartilaginous complex (TFCC) degeneration, faster scanning times, and improved resolution of complex wrist anatomy, allowing differentiation of degenerative from traumatic TFCC tears and improved morphologic evaluation of chondromalacia.

Conclusion: MRI of the wrist and of the musculoskeletal system has had multiple novel and exciting advancements in recent years.

The Peak Site of Stone Distribution in the Upper Ureter is Unlikely the Ureteropelvic Junction: Computed Tomography Analysis of Stone Lodging Site With Respect to a Newly Identified Area of Constriction.

Objective: To investigate the relationship between the upper urinary stone distribution and the "crossing point," an area of relative fixation within the upper ureter at approximately the level where the ureter crosses the gonadal vein.

Materials And Methods: We reviewed 298 consecutive patients presenting with acute renal colic, identified upper ureteral stones in computed tomography. For stones located at the "renal pelvis and upper ureter," we measured the vertebral level of each renal pelvis, crossing point, and stone.

Reliability of MR Quantification of Rotator Cuff Muscle Fatty Degeneration Using a 2-point Dixon Technique in Comparison with the Goutallier Classification: Validation Study by Multiple Readers.

Rationale And Objectives: Presurgical assessment of fatty degeneration is important in the management of patients with rotator cuff tears. The Goutallier classification is widely accepted as a qualitative scoring system, although it is highly observer-dependent and has poor reproducibility. The objective of this study was to quantify fatty degeneration of the supraspinatus muscle using a 2-point Dixon technique in patients with rotator cuff tears by multiple readers, and to evaluate the reproducibility compared to Goutallier classification.

Predicting Retear after Repair of Full-Thickness Rotator Cuff Tear: Two-Point Dixon MR Imaging Quantification of Fatty Muscle Degeneration-Initial Experience with 1-year Follow-up.

Purpose To determine the degree of preoperative fatty degeneration within muscles, postoperative longitudinal changes in fatty degeneration, and differences in fatty degeneration between patients with full-thickness supraspinatus tears who do and those who do not experience a retear after surgery. Materials and Methods This prospective study had institutional review board approval and was conducted in accordance with the Committee for Human Research. Informed consent was obtained.

Quantification of Fatty Degeneration Within the Supraspinatus Muscle by Using a 2-Point Dixon Method on 3-T MRI.

Objective: The objective of this study was to quantify fatty degeneration of the supraspinatus muscle by using a 2-point Dixon technique on 3-T MRI and to evaluate the correlation of muscular atrophy and fat fraction values among different severities of rotator cuff tears across differing ages and sexes.

Subjects And Methods: Patients with shoulder pain (n = 359) were evaluated by shoulder MRI on a 3-T unit, including a 2-point Dixon sequence for quantification of muscle atrophy and fatty degeneration within the supraspinatus muscle. Two board-certified musculoskeletal radiologists evaluated the degree of rotator cuff tears in three groups: full-thickness tear (n = 63), partial tear (n = 54), and no tear (n = 242).