Robustness of a Combined Modified Dixon and PROPELLER Sequence with Two Interleaved Echoes in Clinical Head and Neck MRI.

PURPOSE: The combination of modified Dixon (mDixon) and periodically rotated overlapping parallel lines with enhanced reconstruction sequence with two interleaved echoes, which promotes uniform fat-suppression and motion insensitivity, has recently become available for commercial magnetic resonance imaging (MRI) scanners. To compare the robustness of this combination sequence with that of standard Cartesian mDixon sequence for fat-suppressed T2-weighted imaging in clinical head and neck MRI. METHODS: Fifty patients with head and neck tumors were involved this study. All patients underwent MRI using both the combination and standard sequences. Two radiologists independently scored motion artifacts and water-fat separation error using a 4-point scale (1, unacceptable; 4, excellent). Furthermore, comprehensive comparative evaluation was performed using a 5-point scale (1, substantially inferior; 5, substantially superior). Data were statistically analyzed using the Wilcoxon signed-rank test. RESULTS: In the motion artifact assessment, ratings of 3 or 4 points were assigned to 45% (observer-1, 58.0%; observer-2, 32.0%) and 97% (100%; 94.0%) of images for the standard and combination sequences, respectively (P < 0.001). For the water-fat separation error assessment, ratings of 3 or 4 points were assigned to 100% (100%; 100%) and 85% (84.0%; 86.0%) of images, respectively (P < 0.001). In the comprehensive evaluation, of the 100 cases (observer-1, 50; observer-2, 50), 96 were rated at four or five points. In cases with slight or no motion artifacts and water-fat separation errors, the combination sequence was superior to the standard sequence in term of noise and sharpness, and equal in terms of contrast. CONCLUSION: Although water-fat separation errors increased significantly in the combination sequence, most of these were acceptable. The significantly decreased motion artifacts in the combination sequence significantly improved image quality overall.

Effect of the Cell Alive System on nerve tissue cryopreservation.

Effective cellular cryopreservation while maintaining high cell viability is achieved by preventing intracellular and extracellular ice crystal formation using the Cells Alive System (CAS), a programmed freezer that applies a magnetic field. Here, the optimal temperature settings of the CAS were determined using rat sciatic nerves as a model tissue. Firstly, it was found that Schwann cell survival was increased by pre-cooling the samples in the ice crystal formation zone, increasing the freeze-thaw speed, and freezing-thawing in a magnetic field. Secondly, the setting (intensity and frequency) of the magnetic field at freezing-thawing was changed, and the optimum magnetic field strength was determined by evaluating cell viability. At the set temperature excluding previous studies, the minimum temperature was set to - 50 °C and kept frozen for 15 min, and then thawed immediately. The highest cell viability (27%) was achieved at 0.67 mT (intensity 3 [29.6 V] and frequency setting 10 [60 Hz]). The effects of the freeze-thaw program were assessed using transplanted sciatic nerve tissues removed after 2, 4, and 8 weeks. Anterior tibial muscle wet weight increased at 8 weeks in the control (without freezing) and after freezing-thawing in a magnetic field, compared to that without a magnetic field. Fluorescence staining of the sciatic nerve with anti-S100 antibodies revealed that Schwann cell counts increased at the transplanted site (at 8 weeks) of nerves that were freeze-thawed in a magnetic field. Overall, the CAS prevented ice crystal formation in rat sciatic nerves and could be used to maintain cell viability during cryopreservation.

Combined analysis of V20, VS5, pulmonary fibrosis score on baseline computed tomography, and patient age improves prediction of severe radiation pneumonitis after concurrent chemoradiotherapy for locally advanced non-small-cell lung cancer.

INTRODUCTION: We aimed to develop a more accurate model for predicting severe radiation pneumonitis (RP) after concurrent chemoradiotherapy for non-small-cell lung cancer. METHODS: We retrospectively analyzed data from 122 patients with locally advanced non-small-cell lung cancer treated with concurrent chemoradiotherapy. Several dose-volume histogram metrics including absolute lung volume spared from a 5 Gy dose (VS5) were analyzed for an association with RP above NCI-CTC grade 3 (RP ≥ G3). Clinical factors including pulmonary fibrosis score (PFS) and pulmonary emphysema score on baseline chest computed tomography (CT) were also analyzed. RESULTS: Fourteen patients (11.4%) developed RP greater than or equal to G3. On univariate analysis, all dose-volume histogram metrics, sex, and PFS on baseline CT were significantly (p < 0.05) associated with occurrence of RP greater than or equal to G3. Multivariate analysis revealed that V20 greater than or equal to 26%, VS5 less than 1500 cc, age greater than or equal to 68 years, and PFS on baseline CT greater than or equal to 2 were significant risk factors. Thus, we defined a new predictive risk score (PRS) that combines these factors. The cumulative incidence of RP greater than or equal to G3 at 12 months were 0%, 7.8%, 26.6%, and 71.4% when the PRS was 0, 3-5, 6-8, and 9-14, respectively (p < 0.001). This PRS was superior at predicting RP than both V20 and VS5 combined, or V20 alone by receiver operating characteristic analysis (area under the curve, 0.888 versus 0.779 versus 0.678). CONCLUSIONS: V20, VS5, age, and PFS on baseline CT are independent and significant risk factors for occurrence of severe RP. Combining these factors may improve the predictability of severe RP.

Articular synovial chondromatosis of the finger.

A 40-year-old woman presented with a six-month history of synovial chondromatosis of the metacarpophalangeal joint of the right ring finger, which was resected through both dorsal and volar incisions. To our knowledge there have been only 17 reported cases of articular synovial chondromatosis of the digital joint so far. We present a case affecting the metacarpophalangeal joint with a review of scattered information found in other 17 reports.

Two-stage tendon sheath reconstruction using sublimis tendon and silicone Penrose drain after severe purulent flexor tenosynovitis: a case report.

Two-stage tendon sheath reconstruction, a method of pulley reconstruction using the sublimis tendon and a pseudosheath formed with a silicone Penrose drain wrapped around the profundus tendon, is a new technique for improving a poor functional prognosis after purulent flexor tenosynovitis.

Percutaneous flexible double pinning (Py-Desmanet's procedure) for pediatric distal radius fractures.

PURPOSE: The purpose of this study is to report the results of percutaneous flexible double pinning for pediatric distal radius fractures. METHODS: Thirteen unstable fractures (three physeal and ten metaphyseal) of the distal radius in which the physeal plate could be still identified were treated with percutaneous flexible double pinning between 2008 and 2011. The average age of these cases was 9.8 years (range, 2-16 years). According as Py-Demanet's original technique, the fracture was fixed with two percutaneous transepiphyseal intramedullary wires. Kirschner wires or c-wires of 1.4-1.6 mm in diameter were used in each case depending on age. Operative and short follow-up outcomes were assessed. RESULTS: The average operative duration was 23 min (range, 5-45 min). Comorbid distal ulnar fractures were further stabilized by intramedullary pinning. Additional external splintage was administered in all cases for 6 weeks postoperatively. Wires were removed after an average of 7.2 weeks (range, 4-10 weeks). Bone union was achieved in all cases. Neither malunion nor early epiphyseal closure of the distal radius was identified at mean follow-up of 12 months (range, 3-51 months). DISCUSSION: Flexible double pinning has been successfully used for distal radius fractures in adults. Since this technique is minimally invasive, quick, and technically easy, it is also a good treatment option for unstable distal radius fractures in children. LEVEL OF CLINICAL EVIDENCE: Therapeutic Level IV.

Vascularized genicular osseous-periosteal flap for pseudarthrosis of the proximal phalanx of the little finger: a case report.

This study describes pseudoarthrosis of the proximal phalanx of the little finger and its successful treatment using a free vascularized genicular osseous-periosteal flap. Since this thin and pliable flap can be harvested as a small vascularized unit, it is ideal for the treatment of phalangeal pseudoarthrosis.

A rare nodular fasciitis involving the finger: a case report.

This is a report of a 43-year-old man with nodular fasciitis of the little finger. Nodular fasciitis with its feature of rapid growth and aggressive histological appearance is often mistaken for a malignant neoplasm and rarely involves fingers.

Bilateral popliteal artery entrapment syndrome: reemphasis on reading axial tomograms.

A 33-year-old man with bilateral popliteal artery entrapment syndrome (PAES) presented with right calf claudication. He underwent radiological studies including conventional arteriography, multidetector row CT (MDCT), and magnetic resonance imaging (MRI) of the lower extremities. He had been fine since birth and athletic in his school days. Axial tomographic images by MDCT and MRI at the popliteal fossa bilaterally showed an anomalous medial head of the gastrocnemius muscle between the popliteal artery and vein, resulting in right popliteal artery occlusion and leading to the diagnosis of bilateral PAES type II. MDCT or MR facilitates noninvasive computer-aided arteriography and is often utilized for screening patients with claudication for peripheral arterial diseases. However, axial tomograms are more essential for confirming PAES than arteriography, and radiologists should continue to look for possible abnormalities on popliteal fossa tomograms because early diagnosis of PAES allows better choices and outcomes of treatment.