Metal Artifact Reduction in Virtual Monoenergetic Spectral Dual-Energy CT of Patients With Metallic Orthopedic Implants in the Distal Radius.

OBJECTIVE: The purpose of this study was to evaluate the image quality of virtual monoenergetic images obtained from dual-layer-detector spectral CT of patients with metallic orthopedic implants of the distal radius. MATERIALS AND METHODS: A retrospective analysis was performed between April 2016 and January 2017. Forty-three consecutively registered patients (33 women, 10 men; mean age, 50.7 ± 15.4 years) with metallic implants for distal radius fractures underwent dual-layer-detector spectral CT. Sixteen virtual monoenergetic image sets ranging from 50 to 200 keV were generated from the single slice with the most pronounced low-attenuation artifact from implants. Image quality was quantitatively assessed on the basis of the attenuation of the artifacts and reference tissue, background image noise, and artifact index. Qualitative assessment included degree of artifact, diagnostic image quality of the periimplant bones, and delineation of fracture lines. The Friedman rank sum test and kappa analysis were used for statistical analysis. RESULTS: There were statistically significant differences in quantitative and qualitative parameters at different monoenergy levels (all p < 0.001). Artifact index was the lowest at 120 keV. Low-attenuation artifacts in the periimplant regions were least pronounced at 110 keV, and the diagnostic image quality of periimplant bone was best at 130 keV. Fracture lines were well delineated in all cases at 80-110 keV (p < 0.001). CONCLUSION: The optimal energy setting for incurring the fewest metallic artifacts and obtaining the best diagnostic image quality from distal radius implants during dual-layer-detector spectral CT is the range of 110-130 keV.

MRI of Cuboid Pulley Lesion.

OBJECTIVE: The aim of this study was to describe cuboid pulley lesions and associated abnormalities on the basis of clinical findings and the results of MRI examinations of the ankle. MATERIALS AND METHODS: A retrospective search was performed to identify patients who had a cuboid pulley lesion during a 10-year period. A cuboid pulley lesion was defined as bone marrow edema in the lateroplantar ridge of the cuboid that was shown to be wrapped by the peroneus longus tendon on MRI of the ankle. A total of 19 patients (11 men and eight women; mean age, 45.4 years) were included in the group of patients with a cuboid pulley lesion, and 38 age-and sex-matched patients without a cuboid pulley lesion were randomly selected as the control group. We reviewed medical records and assessed MRI findings that could be associated with a cuboid pulley lesion. RESULTS: The mean (± SD) diameter of the cuboid pulley lesion was 8.9 ± 4.7 mm. Cuboid pulley lesions were associated with peroneal tenosynovitis (p < 0.001), Achilles enthesitis (p = 0.004), and a clinical diagnosis of inflammatory arthritis (p < 0.001). Eleven of the 19 patients in the group with cuboid pulley lesions had inflammatory arthritis (either rheumatoid arthritis [n = 7] or spondyloarthritis [n = 4]). The cuboid pulley lesions did not cause localized lateral foot pain and tenderness, except in one patient who had an accompanying stress fracture of the cuboid. CONCLUSION: MRI of the ankle rarely but clearly shows cuboid pulley lesions, which themselves are not likely to cause localized pain, and cuboid pulley lesions show significant associations with peroneal tenosynovitis, Achilles enthesitis, and clinically diagnosed inflammatory arthritis.

A 12-Year Retrospective Study of Survival Rates and Outcomes of Very Low Birth Weight Infants in a Single Center

PURPOSE: To investigate the outcomes and survival rates of very low birth weight infants (VLBWI) born over a 12-year period in a single center. METHODS: A retrospective review of 613 VLBWI born from January 2000 to December 2011 was performed. We compared the incidence, survival rate, and morbidity of infants classified according to their birth weight or gestational age for the following periods: Period I (2000-2002), Period II (2003-2005), Period III (2006-2008), and Period IV (2009-2011). RESULTS: The incidence of VLBWI was 0.7%, while the overall survival rate was 94.9%. The survival rates were 92.8%, 92.9%, 95.9%, and 97.5% for periods I, II, III and IV, respectively; the rates improved significantly over time (P or =grade III), 8.5%; sepsis, 6.5%; cystic periventricular leukomalacia, 3.8%; necrotizing enterocolitis (> or =grade II), 3.4%; and intraventricular hemorrhage (> or =grade III), 2.3%. A significant decrease was seen in some clinical parameters: the time to start feeding, duration of parenteral nutrition, and duration required to reach full enteral feeding in every successive three-year period (P<0.01). CONCLUSION: The overall survival rate of VLBWI born between January 2000 and December 2011 was 94.9%. This survival rate was found to increase significantly in each successive three-year period starting January 2000.

Ultrasound assessment of degrees of extrathyroidal extension in papillary thyroid microcarcinoma.

OBJECTIVE: This study aimed to assess the diagnostic accuracy of ultrasound (US)-based T staging of papillary thyroid microcarcinoma (PTMC). METHODS: From January to June 2013, a total of 185 patients underwent preoperative thyroid US for the treatment of thyroid malignancy. A single radiologist immediately determined sonographic T staging for PTMC during real-time US examination. Based on histopathologic results, the diagnostic accuracy of sonographic T staging for PTMC and the difference in the frequency of level VI node metastasis according to the T stage of PTMC were evaluated. RESULTS: Of 105 PTMC cases, the preoperative sonographic diagnoses included intraglandular location (n = 35), subcapsular location (n = 30), mild capsule abutment (n = 7), moderate capsule abutment (n = 19), and perithyroidal invasion without adjacent strap muscle invasion (n = 14). When the sonographic T stages were compared with histopathologic results, all the sonographic categories showed high specificity and low sensitivity. The intraglandular and subcapsular location cases in preoperative US diagnosis showed a low rate of extrathyroidal tumor invasion (6.2%, 4/65). The extrathyroidal tumor invasion cases in preoperative US diagnosis only included 26 extrathyroidal fat invasion cases, and 12 (46.2%, 12/26) true positives. There was a significant correlation between multifocality and histopathologic T stage, but no significant relationship between level VI node metastasis and histopathologic T stage was found. CONCLUSION: The sonographic T staging categorization described here may be helpful for the preoperative evaluation of PTMC patients.

Unusual Presentation of Calcinosis Cutis: Venous Calcification Following intravenous Calcium Gluconate Administration in a Preterm Baby

Neonatal hypocalcemia is not uncommon, especially in premature neonates. It is usually treated by intravenous calcium gluconate administration. However, complications caused by the extravasation of intravenous calcium gluconate include calcinosis cutis, calcium deposition in the dermis, which is irritating to soft tissues and can produce tissue necrosis. We report a case of iatrogenic calcinosis cutis in a 27-day-old preterm baby following the extravasation of calcium gluconate. In this case, calcinosis cutis occurred along the venous pathway in a rare vascular calcification pattern but spontaneously resolved 2 months later. Although iatrogenic calcinosis cutis is generally benign, early recognition of the extravasation of calcium gluconate is important to avoid severe complications. This report aimed to provide a warning about the risks associated with intravenous calcium gluconate and information about the course of a rare presentation of the common disease calcinosis cutis with vascular calcification.