Comparison of 2D Thin Section Dixon, 3D Isotropic SPACE, and 2D T2-Weighted Sequences in Ankle MRI

Purpose@#This study aimed to conduct a comparison between 2D thin section intermediate-weighted Dixon turbo spin echo (TSE), 3D intermediate-weighted SPACE (sampling perfection with application-optimized contrasts using flip angle evolutions) TSE, and 2D fat-suppressed T2-weighted TSE in terms of their image quality and diagnostic performance for ankle ligament evaluation. @*Materials and Methods@#Thirty-eight ankle MRI studies were retrospectively analyzed. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the multiplanar reformation images of the sequences were obtained. For each sequence, the subjective image quality and the diagnostic performance for ankle ligament tear were analyzed. @*Results@#The Dixon demonstrated the highest CNR both between ligament and fluid and between ligament and bone marrow. The 3D SPACE showed the highest SNR of the ligament. Regarding subjective image quality, it was significantly higher in the T2-weighted image than it was in the SPACE (p < 0.05), while there was no significant difference between the Dixon and the SPACE. The Dixon showed the highest sensitivity for anterior talofibular ligament (ATFL) tear (80.0%; 95% confidence interval [CI], 64.4–92.3) and deep deltoid ligament (DL) tear (86.4%; 95% CI, 65.1–97.1), and it showed the highest specificity for ATFL tear (70.2%; 95% CI, 59.3–79.7). The interobserver agreement was moderate to good (intraclass correlation coefficient [ICC], 0.50–0.93) in most cases except for the SNR of deep DL (ICC of 0.35–0.62). @*Conclusion@#For ankle ligament evaluation, the 2D thin section Dixon provides adequate image quality with high SNR and CNR and the highest sensitivity for detecting tears.

Triaging deep vein thrombosis using ultrasonography after lower-extremity orthopedic surgery: analysis of a single-center experience

Purpose@#This study aimed to stratify risk factors and vein levels for postoperative deep vein thrombosis (DVT) after lower-extremity orthopedic surgery. @*Methods@#Ninety-nine patients who underwent Doppler ultrasonography after lower-extremity orthopedic surgery were enrolled. Medical records were reviewed for anesthesia duration, type of surgery, body weight, height, and cardiovascular risk factors (including history of smoking, diabetes mellitus or hypertension, blood pressure, and total cholesterol and high-density lipoprotein [HDL] cholesterol levels), and the DVT treatment. Ultrasound diagnosis of DVT was made according to a routine protocol. The relationships between selected factors and the presence of DVT were assessed using univariate and multivariate regression analyses. @*Results@#Thirty-three (33%) patients were found to have calf DVT. The mean age, weight, and height of the non-DVT and postoperative DVT patients were 55.1 years versus 65.4 years, 70.5 kg versus 61.2 kg, and 163.3 cm versus 157.0 cm, respectively. Total cholesterol/HDL levels in the non-DVT and DVT patients were 70.6/20.7 mg/dL and 90.8/26.0 mg/dL, retrospectively. Systolic and diastolic blood pressure in the non-DVT and DVT patients were 133.6/80.2 mm Hg and 132.2/78.1 mmHg, respectively. The mean duration of anesthesia was 173.9 versus 199.9 minutes, and the operative time was 136.4 minutes versus 161.0 minutes. Older age (P=0.005) and lower body weight (P=0.002) were significantly associated with postoperative DVT. No other significant between-group differences were found (P>0.05). The patients with ultrasound-identified DVT received antithrombotic treatment. None of them had distant thromboembolism. @*Conclusion@#After lower-extremity orthopedic surgery, the calf veins in elderly patients with low body weight are susceptible to thrombosis; they would most likely benefit from postoperative ultrasonography.

Susceptibility Weighted Imaging of the Cervical Spinal Cord with Compensation of Respiratory-Induced Artifact

PURPOSE: The objective of this study was to obtain improved susceptibility weighted images (SWI) of the cervical spinal cord using respiratory-induced artifact compensation. MATERIALS AND METHODS: The artifact from B0 fluctuations by respiration could be compensated using a double navigator echo approach. The two navigators were inserted in an SWI sequence before and after the image readouts. The B0 fluctuation was measured by each navigator echoes, and the inverse of the fluctuation was applied to eliminate the artifact from fluctuation. The degree of compensation was quantified using a quality index (QI) term for compensated imaging using each navigator. Also, the effect of compensation was analyzed according to the position of the spinal cord using QI values. RESULTS: Compensation using navigator echo gave the improved visualization of SWI in cervical spinal cord compared to non-compensated images. Before compensation, images were influenced by artificial noise from motion in both the superior (QI = 0.031) and inferior (QI = 0.043) regions. In most parts of the superior regions, the second navigator resulted in better quality (QI = 0.024, P < 0.01) compared to the first navigator, but in the inferior regions the first navigator showed better quality (QI = 0.033, P < 0.01) after correction. CONCLUSION: Motion compensation using a double navigator method can increase the improvement of the SWI in the cervical spinal cord. The proposed method makes SWI a useful tool for the diagnosis of spinal cord injury by reducing respiratory-induced artifact.

Evaluation of Knee Joint after Double-Bundle ACL Reconstruction with Three-Dimensional Isotropic MRI

PURPOSE: To evaluate the knee joint after double-bundle anterior cruciate ligament (ACL) reconstruction with three-dimensional (3D) isotropic magnetic resonance (MR) image, and to directly compare the ACL graft findings on 3D MR with the clinical results. MATERIALS AND METHODS: From January 2009 to December 2014, we retrospectively reviewed MRIs of 39 patients who had reconstructed ACL with double bundle technique. The subjects were examined using 3D isotropic proton-density sequence and routine two-dimensional (2D) sequence on 3.0T scanner. The MR images were qualitatively evaluated for the intraarticular curvature, graft tear, bony impingement, intraosseous tunnel cyst, and synovitis of anteromedial and posterolateral bundles (AMB, PLB). In addition anterior tibial translation, PCL angle, PCL ratio were quantitatively measured. KT arthrometric values were reviewed for anterior tibial translation as positive or negative. The second look arthroscopy results including tear and laxity were reviewed. RESULTS: Significant correlations were found between an AMB tear on 3D-isotropic proton density MR images and arthroscopic proven AMB tear or laxity (P < 0.05). Also, a significant correlation was observed between increased PCL ratio on 3D isotropic MRI and the arthroscopic findings such as tear, laxities of grafts (P < 0.05). KT arthrometric results were found to be significantly correlated with AMB tears (P < 0.05) and tibial tunnel cysts (P < 0.05). CONCLUSION: An AMB tear on 3D-isotropic MRI was correlated with arthroscopic results qualitatively and quantitatively. 3D isotropic MRI findings can aid the evaluation of ACL grafts after double bundle reconstruction.

Fracture Healing Effects of Locally-Administered Adipose Tissue-Derived Cells

PURPOSE: Although the applications of adipose tissue-derived cells (ADCs) in regenerative medicine have been investigated, the role of ADCs in fracture healing remains unclear. In this study, we examined the fracture-healing effects and survival of transplanted ADCs using micro-computed tomography (CT) and bioluminescence imaging (BLI). MATERIALS AND METHODS: Luciferase-expressing ADCs were suspended in solubilized basement membrane preparation (SBMP) and xenografted on defects in the right femur of nude mice (n=5). SBMP alone was grafted on a defect in the contralateral femur. Serial in vivo micro-CT and BLI were performed for 20 days. Ex vivo BLI images of both femurs were obtained. Differences in the Hounsfield unit (HU), HUratio, and luciferase activities were compared using Wilcoxon signed-rank tests and non-parametric longitudinal analyses (p<0.05). RESULTS: In vivo BLI revealed a signal drop on day 2, reconstitution on day 5, and continuous decrement thereafter. Ex vivo BLI revealed residual activity in the ADC-implanted and adjacent areas. No activity was detected in the contralateral femur. The overall increment rate of normalized HUs was higher for ADC-treated femurs than for SBMP-treated femurs. Cell migration to distant injury sites was not detected. CONCLUSION: Enhanced bone density in the implant area suggests that ADCs have fracture-healing effects.

Comparison of Radiation Exposure during Fluoroscopy-Guided Transforaminal Epidural Steroid Injections at Different Vertebral Levels

OBJECTIVE: To estimate and compare radiation exposure during transforaminal fluoroscopy-guided epidural steroid injection (TFESI) at different vertebral levels. MATERIALS AND METHODS: Fluoroscopy-guided TFESI was performed in 181 patients. The patients were categorized into three groups according to the injected lumbosacral nerve level of L2-4, L5, or S1. Fluoroscopy time (FT) and dose area product (DAP) were recorded for all patients; correlations between FT and DAP were determined at each level, and both FT and DAP were compared between the different vertebral levels. RESULTS: The numbers of patients who received ESI at L2-4, L5, and S1 were 29, 123, and 29. Mean FT was 44 seconds at L2-4, 33.5 seconds at L5, and 37.7 seconds at S1. Mean DAP was 138.6 microGy.m2 at L2-4, 100.6 microGy.m2 at L5, and 72.1 microGy.m2 at S1. FT and DAP were positively correlated in each group (p values < 0.001). FT was significantly shorter at L5 than that at L2-4 (p = 0.004) but was not significantly different between S1 and L2-4 or L5 (p values = 0.286 and 0.532, respectively). DAP was significantly smaller at L5 and S1 than that at L2-4, but L5 and S1 were not significantly different. After correcting for FT, DAP was significantly smaller at S1 than that at either L2-4 or L5 (p values = 0.001 and 0.010). CONCLUSION: The radiation dose was small during a single procedure of ESI and showed differences between different lumbosacral spine levels.

Candida Septic Arthritis with Rice Body Formation: A Case Report and Review of Literature

Rice body formation in a joint or bursa is a rare condition, and is usually associated with rheumatoid arthritis or tuberculous arthritis. Here we describe a case of multiple rice body formation in a shoulder joint and in adjacent bursae, which was confirmed to be due to septic arthritis by Candida species. To the best of our knowledge, rice body formation in Candida septic arthritis in an immune-competent patient has not been previously reported.

Assessment of Collagen-Induced Arthritis Using Cyanine 5.5 Conjugated with Hydrophobically Modified Glycol Chitosan Nanoparticles: Correlation with 18F-Fluorodeoxyglucose Positron Emission Tomography Data

OBJECTIVE: To evaluate the potential and correlation between near-infrared fluorescence (NIRF) imaging using cyanine 5.5 conjugated with hydrophobically modified glycol chitosan nanoparticles (HGC-Cy5.5) and 18F-fluorodeoxyglucose-positron emission tomography (18F-FDG-PET) imaging of collagen-induced arthritis (CIA). MATERIALS AND METHODS: We used 10 CIA and 3 normal mice. Nine days after the injecting collagen twice, microPET imaging was performed 40 minutes after the intravenous injection of 9.3 MBq 18F-FDG in 200 microL PBS. One day later, NIRF imaging was performed two hours after the intravenous injection of HGC-cy5.5 (5 mg/kg). We assessed the correlation between these two modalities in the knees and ankles of CIA mice. RESULTS: The mean standardized uptake values of 18F-FDG for knees and ankles were 1.68 +/- 0.76 and 0.79 +/- 0.71, respectively, for CIA mice; and 0.57 +/- 0.17 and 0.54 +/- 0.20 respectively for control mice. From the NIRF images, the total photon counts per 30 mm2 for knees and ankles were 2.32 +/- 1.54 x 10(5) and 2.75 +/- 1.51 x 10(5), respectively, for CIA mice, and 1.22 +/- 0.27 x 10(5) and 0.88 +/- 0.24 x 10(5), respectively, for control mice. These two modalities showed a moderate correlation for knees (r = 0.604, p = 0.005) and ankles (r = 0.464, p = 0.039). Moreover, both HGC-Cy5.5 (p = 0.002) and 18F-FDG-PET (p = 0.005) imaging also showed statistically significant differences between CIA and normal mice. CONCLUSION: NIRF imaging using HGC-Cy5.5 was moderately correlated with 18F-FDG-PET imaging in the CIA model. As such, HGC-Cy5.5 imaging can be used for the early detection of rheumatoid arthritis.

Nodular Fasciitis in the Finger: The Sonographic Findings and a Literature Review

A 39-year-old woman presented with a rapidly growing nodule on the right thumb. An ultrasound study demonstrated a mass located in the deep subcutaneous tissue on the ulnar side of the interphalangeal joint. Incisional biopsy yielded the diagnosis of nodular fasciitis. We discuss the ultrasound appearance of nodular fasciitis as reported in the literature and how to make the differential diagnosis of an echogenic finger mass.

The Diagnostic Role of US in Patients with Right Lower Quadrant Abdominal Pain

PURPOSE: To determine the frequency with which ultrasonography (US) provides a correct diagnosis and suggests appropriate guidance for the treatment of patients with right lower quadrant abdominal pain. MATERIALS AND METHODS: During an 11-month period, US was consecutively performed in 84 patients who were presented with right lower quadrant abdominal pain. In the 76 [M ; F=16 ; 60, age range 14 -87 (mean, 41) years] who formed the study population, final diagnoses were made surgically or clinically. For US, a 5 -7-MHz convex-array, 4-MHz vector-array, and/or 7-MHz linear-array transducer was used, according to the patient 's body habitus. To determine how often our US reports had provided a correct diagnosis and suggested appropriate guidance for surgical or medical treatment, and to calculate their diagnostic value, the reports were retrospectively compared with final diagnoses. RESULTS: US diagnoses were acute appendicitis in 40 patients (53%), diseases other than this in 25 patients (33%), and no abnormality in 11 (14%). In 38 of the 40 patients (95%), the diagnosis of acute appendicitis was surgically confirmed as correct, and for other diseases, diagnoses based on the findings of US proved to be correct in 21 of 25 patients (84%). Overall, diagnosis was correct in 67 (88%). As regards appropriate guidance for treatment, 46 (61%) and 30 (39%) patients were diagnosed by US to have surgical and medical diseases, respectively. In 44 of the 46 (96%), it was confirmed guidance was appropriate, and for the 30 with medical disease, this was so in all but one case (97%). Overall, the treatment plan was appropriate in 72 patients (95%). CONCLUSION: Our study revealed that US was able to provide a correct diagnosis in 88% of patients with right lower quadrant abdominal pain, and in 95% of these, the treatment plan suggested was appropriate. US is, therefore, a valuable screening tool in the diagnosis and therapeutic guidance of such patients.