Ultrashort echo time pulse sequences for visualization of deep peripheral fasciae and epimysium in porcine models with histologic correlations.

Background: The deep peripheral fascia and epimysium are vital for muscle and tendon support, but their tight proton composition results in hypointense signals in conventional spin echo sequences. Ultrashort echo time (UTE) magnetic resonance imaging (MRI), using microsecond TE values, may visualize these structures. The purpose of this study was to evaluate whether UTE pulse sequence with a three-dimensional cone trajectory (3D UTE), with or without fat suppression (FS), can be used to visualize the fascia and epimysium using porcine lower legs as an example. Methods: The anterior soft tissues of porcine lower legs were dissected and partially separated into distinct layers to expose the deep peripheral fascia, epimysium, and muscle. Axial 3D UTE and 3D UTE FS imaging using dual-echo acquisition and echo subtraction were performed both before and after dissection. Prior to dissection, the thickness, signal-to-noise ratios (SNRs), and contrast-to-noise ratios (CNRs) of structures believed to be deep peripheral fascia and epimysium were measured in both 3D UTE and 3D UTE FS. Post-dissection images were also analyzed to measure the SNRs and CNRs for the deep peripheral fascia and epimysium. Histological evaluations were carried out to verify the identities of the deep peripheral fascia and epimysium, as well as their thickness, and these measurements were compared to imaging findings. Results: In pre-dissection images obtained with 3D UTE and 3D UTE FS, both the deep peripheral fascia and epimysium exhibited high signal intensity. In the subtraction images, the mean thickness of the deep fascia was 0.87 mm, and that of the epimysium was 0.80 mm when imaged with 3D UTE. This is compared to measurements of 0.77 and 0.22 mm in 3D UTE FS, respectively. Histological analyses confirmed the thickness of the deep peripheral fascia and epimysium as 0.65 and 0.14 mm, respectively. In the post-dissection images, the deep fascia continued to display high signal intensity when compared with adjacent soft tissues, consistent with the histological findings. Meanwhile, the epimysium showed very low CNRs. Conclusions: 3D UTE and 3D UTE FS can be used to visualize the deep peripheral fascia with high signal intensity and contrast but are insufficient to show signal intensity in the epimysium.

Characteristics, trend, and methodological quality of systematic reviews and meta-analyses in nuclear medicine: A bibliometric analysis of studies published between 2005 and 2016.

To evaluate the characteristics, trend, and quality of systematic reviews and meta-analyses in nuclear medicine.We performed a PubMed search to identify systematic reviews and meta-analyses published between 2005 and 2016 in the field of nuclear medicine. The following data were extracted: journal name, impact factor, type of study, topics with cancer type, imaging modalities, authors (number, country, affiliation, presence of nuclear medicine specialists and statisticians, discordance between the first and corresponding authors), funding, methodological quality, methods used for quality assessment, and statistical methods.We included 185 nuclear medicine articles. Meta-analyses (n = 164; 88.6%) were published about 7 times more frequently than systematic reviews. Oncology was the most commonly studied topic (n = 125, 67.6%). The first authors were most frequently located in China (n = 73; 39.5%). PET was the most commonly used modality (n = 150; 81.1%). Both the number of authors and the ratio of discordance between the first and corresponding authors tended to progressively increase over time.The mean AMSTAR score increased over time (5.77 in 2005-2008, 6.71 in 2009-2012, and 7.44 in 2013-2016). The proportion of articles with quality assessment increased significantly (20/26 in 2005-2008, 54/65 in 2009-2012, and 79/94 in 2013-2016). The most commonly used assessment tool was quality assessment of diagnostic accuracy studies (n = 85; 54.9%).The number and quality of systematic reviews and meta-analyses in nuclear medicine have significantly increased over the review period; however, the quality of these articles varies. Efforts to overcome specific weaknesses of the methodologies can provide opportunities for quality improvement.

Incidental Paratracheal Air Cysts on Thoracic CT and Their Association with Chronic Inflammatory Lung Disease.

Purpose. To determine the association between the progression of upper lung fibrosis and paratracheal air cysts (PACs) size. Materials and Methods. The thoracic CT images of 4573 patients were reviewed for the prevalence, size, and location of PACs and their communication with trachea. In addition, the presence of upper lung fibrosis, emphysema, and bronchiectasis was evaluated in patients with PACs and compared with a control group without PACs. Upper lung fibrosis was analyzed using a fibrosis score system. Results. The prevalence of PACs was 6.8%. Communication with tracheal lumen was demonstrated by 31.5% of patients with PACs. The prevalence of fibrosis, emphysema, and bronchiectasis in patients with PACs were 67.5%, 21.9%, and 28.3%, respectively. The prevalence of fibrosis was significantly different in the two groups by univariable and multivariable analysis (odds ratio = 2.077, P < 0.001). 140 patients with fibrosis among PAC group underwent a previous or follow-up CT; the prevalence with increase in PAC sizes was higher in patients with increase in fibrosis score than those without it (66.2% versus 17.3%, P < 0.001). Conclusions. PACs appear to be highly related to upper lung fibrosis and moderately related to bronchiectasis. In patients with fibrosis, PAC sizes tended to increase with the progression of upper lung fibrosis.

Incidental thyroid nodules on thoracic contrast-enhanced computed tomography in clinical practice during a 10-year period: Characteristics, clinical outcomes, and factors contributing to further evaluation.

The purposes of this study were to assess the prevalence, malignancy rate, and characteristics of incidental thyroid nodules (ITNs), and to identify factors that contribute the additional workup by ultrasound.The medical records and imaging features of ITNs reported via thoracic computed tomography (CT) were retrospectively reviewed to determine the size, multiplicity, attenuation, shape, and presence of calcification. To identify the factors associated with additional workup, we compared the workup and non-workup groups in terms of nodule characteristics, indications, and CT slices. We identified factors that could distinguish malignant ITNs from non-malignant nodules.A total of 60,921 thoracic CT scans met the inclusion criteria, and ITNs were reported using formal radiology in 2733 patients (4.5%). Among all patients with reported ITNs, 546 (20.0%) underwent further workup. Of these patients, 62 (2.3%, 62/2773) were diagnosed with malignant nodules. Multivariable analysis identified multiple factors associated with additional workup, including female sex, younger age, larger nodule size, calcification, anteroposterior to transverse dimension ratio >1, heterogeneous attenuation in the nodule, and scanning indications such as infection or screening. However, only calcification was associated with malignant nodules (odds ratio [OR] = 2.313; 95% confidence interval [CI], 1.301-4.113).We observed discordance between the numbers of reported ITNs and case with additional workup and identified multiple factors associated with additional workup. We have, therefore, demonstrated a need for reliable subsequent evaluation guidelines and note that the appearance of calcification in an ITN on imaging may be a factor indicating the need for additional workup.

Computed Tomography Features of Appendiceal Metastasis in Patients With Underlying Malignancy: Comparison With Pathological Findings.

OBJECTIVE: To evaluate the computed tomography (CT) findings compared with pathologic features and to determine whether CT findings are useful for diagnosis of appendiceal metastasis in patients with underlying malignancy. MATERIALS AND METHODS: Preoperative CT examinations of 59 patients who had underlying malignancy and underwent appendectomy were evaluated. Appendiceal metastasis (n = 21) and nonmetastasis (n = 38) were pathologically confirmed. Computed tomography features (appendiceal morphology and diameter, presence of ascites, rectal shelf, omental cake, lymphadenopathy or organ metastasis) were retrospectively reviewed, and compared with histopathological findings. Fisher exact test and Wilcoxon rank sum test were performed for statistical analysis. RESULTS: Mean diameter of appendiceal metastasis was significantly larger (9.1 mm) than that of nonmetastasis (5.2 mm), (P < 0.0001). The CT morphology of appendiceal metastasis showed broad spectrum, and 3 cases of nodular thickening was only detected in appendiceal metastasis. There was a significant difference between groups (P = 0.0102). Appendiceal metastasis was more frequently associated with peritoneal seeding (ascitis, rectal shelf, omental cake) than nonmetastasis (P < 0.0001). Histopathological invasion of appendiceal metastasis was more frequently seen in serosa-mesoappendix (n = 20, 100%) or muscularis propria (n = 17, 85%), than in submucosa (n = 10, 50%) or mucosa layer (n = 7, 35%). Acute appendicitis was more commonly detected in metastasis (n = 4) than in nonmetastasis (n = 1) (P = 0.0495). CONCLUSIONS: Evaluation of CT features of appendix and peritoneum may be useful for prediction of appendiceal metastasis in patients with underlying malignancy.

Sonographic Differentiation Between Angiolipomas and Superficial Lipomas.

OBJECTIVES: The purpose of this study was to compare the sonographic findings of angio lipomas with those of superficial lipomas. METHODS: Preoperative sonograms of 26 angiolipomas from 18 patients and 47 superficial lipomas from 43 patients that were confirmed by biopsy were reviewed retrospectively. The echo texture, echogenicity, internal echogenic stranding, vascularity, visualization of lateral and superficial-deep tumor capsules, shape, and tumor length, width, and length-to-width ratio were evaluated and compared between angiolipomas and superficial lipomas. RESULTS: Angiolipomas frequently appeared as heterogeneous (19 of 26 [73.1%]), hyperechoic (23 of 26 [88.5%]), and ovoid (17 of 26 [65.4%]) masses with lesser visualized lateral tumor capsules (6 of 26 [23.1%]), whereas superficial lipomas appeared as homogeneous (36 of 47 [76.6%]), isoechoic (35 of 47 [74.5%]), and spindle-shaped (23 of 47 [48.9%]) masses with well-visualized lateral capsules (33 of 47 [70.2%]), and the differences were statistically significant (P < .001). Vascularity was seen in 4 angiolipomas (16.7%) and in no superficial lipomas (0%). The mean length and width ± SD of angiolipomas (2.2 ± 1.02 and 0.6 ± 0.27 cm, respectively) were smaller than those of superficial lipomas (4.2 ± 1.52 and 1.1 ± 0.51 cm), with statistical significance (P< .001). The other sonographic findings did not reveal statistically significant differences between the tumor types. CONCLUSIONS: Sonography might help differentiate angiolipomas from superficial lipomas.

Superficial Fascia (SF) in the Cheek and Parotid Area: Histology and Magnetic Resonance Image (MRI).

BACKGROUND: The aim of this study is to compare the superficial fascia (SF) in the cheek and parotid areas histologically and through MRI. METHODS: An in vitro study included a histological report and an MRI of the cheek of two Korean adult cadavers. The in vivo study included 100 MRI images and three axial image cuts (mandibular condyle, notch, and half the distance between the top of the condyle and the angle). Four angles, one length, and four thicknesses were measured and compared. RESULTS: The MRI results were in concord with the gross specimen or histology. The SF consisted of multilayered horizontal and vertical fibrous connective tissues at all three levels in both the histology and MRI. In the cheek, both histology and MRI showed horizontal fibrous connective tissues which were connected with the zygomaticus major, visualized as a continuous membrane (membranous layer, MSF). MSF divided the SF into the superficial fatty layer (SFS) and the deep fatty layer. The thickness of the SF depended upon the thickness of the SFS since the thickness of the MSF was very similar irrespective of the three levels. The thickness of the SFS was thicker in females than in males. At the condyle level, the AS-PS angle (AP line-the most posterior superficial fascia angle) and AS-PS length increased significantly (p = 0.001, y = 0.15x + 16.19, and p < 0.001, y = 0.33x + 14.68, respectively). CONCLUSION: We hope the information we have gathered could be useful to provide subcutaneous dissection or sub-SMAS dissection in facelift surgeries. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Paralytic Ileus and Prophylactic Gastrointestinal Motility Medication after Spinal Operation.

PURPOSE: To investigate the prevalence of paralytic ileus after spinal operation in the supine or prone operative position and to determine the efficacy of prophylactic gastrointestinal motility medications in preventing symptomatic paralytic ileus after a spinal operation. MATERIALS AND METHODS: All patients received spinal surgery in the supine or prone operative position. The study period was divided into two phases: first, to analyze the prevalence of radiographic and symptomatic paralytic ileus after a spinal operation, and second, to determine the therapeutic effects of prophylactic gastrointestinal motility medications (postoperative intravenous injection of scopolamine butylbromide and metoclopramide hydrochloride) on symptomatic paralytic ileus after a spinal operation. RESULTS: Basic demographic data were not different. In the first phase of this study, 27 patients (32.9%) with radiographic paralytic ileus and 11 patients (13.4%) with symptomatic paralytic ileus were observed. Radiographic paralytic ileus was more often noted in patients who underwent an operation in the prone position (p=0.044); whereas the occurrence of symptomatic paralytic ileus was not different between the supine and prone positioned patients (p=0.385). In the second phase, prophylactic medications were shown to be ineffective in preventing symptomatic paralytic ileus after spinal surgery [symptomatic paralytic ileus was observed in 11.1% (4/36) with prophylactic medication and 16.7% (5/30) with a placebo, p=0.513]. CONCLUSION: Spinal surgery in the prone position was shown to increase the likelihood of radiographic paralytic ileus occurrence, but not symptomatic paralytic ileus. Unfortunately, the prophylactic medications to prevent symptomatic paralytic ileus after spine surgery were shown to be ineffective.

Primary squamous cell carcinoma in the chest wall mimicking abscess.

We report a case of squamous cell carcinoma (SCC) presenting a painful cystic mass which originated from the chest wall with bony destructions. The patient underwent complete excision with chest wall reconstruction. Although the imaging characteristics of chest wall tumor can be variable, SCC should be considered in differential diagnosis in the case of symptomatic cystic mass in elderly patients.

Computed tomography and magnetic resonance imaging findings of nasal cavity hemangiomas according to histological type.

OBJECTIVE: To compare computed tomography (CT) and magnetic resonance imaging (MRI) findings between two histological types of nasal hemangiomas (cavernous hemangioma and capillary or lobular capillary hemangioma). MATERIALS AND METHODS: CT (n = 20; six pre-contrast; 20 post-enhancement) and MRI (n = 7) images from 23 patients (16 men and seven women; mean age, 43 years; range, 13-73 years) with a pathologically diagnosed nasal cavity hemangioma (17 capillary and lobular capillary hemangiomas and six cavernous hemangiomas) were reviewed, focusing on lesion location, size, origin, contour, enhancement pattern, attenuation or signal intensity (SI), and bony changes. RESULTS: The 17 capillary and lobular hemangiomas averaged 13 mm (range, 4-37 mm) in size, and most (n = 13) were round. Fourteen capillary hemangiomas had marked or moderate early phase enhancement on CT, which dissipated during the delayed phase. Four capillary hemangiomas on MRI showed marked enhancement. Bony changes were usually not seen on CT or MRI (seen on five cases, 29.4%). Half of the lesions (2/4) had low SI on T1-weighted MRI images and heterogeneously high SI with signal voids on T2-weighted images. The six cavernous hemangiomas were larger than the capillary type (mean, 20.5 mm; range, 10-39 mm) and most had lobulating contours (n = 4), with characteristic enhancement patterns (three centripetal and three multifocal nodular), bony remodeling (n = 4, 66.7%), and mild to moderate heterogeneous enhancement during the early and delayed phases. CONCLUSION: CT and MRI findings are different between the two histological types of nasal hemangiomas, particularly in the enhancement pattern and size, which can assist in preoperative diagnosis and planning of surgical tumor excision.

Cervical arthroplasty for moderate to severe disc degeneration: clinical and radiological assessments after a minimum follow-up of 18 months--Pfirrmann grade and cervical arthroplasty.

PURPOSE: Clinical outcomes and radiologic results after cervical arthroplasty have been reported in many articles, yet relatively few studies after cervical arthroplasty have been conducted in severe degenerative cervical disc disease. MATERIALS AND METHODS: Sixty patients who underwent cervical arthroplasty (Mobi-C®) between April 2006 and November 2011 with a minimum follow-up of 18 months were enrolled in this study. Patients were divided into two groups according to Pfirrmann classification on preoperative cervical MR images: group A (Pfirrmann disc grade III, n=38) and group B (Pfirrmann disc grades IV or V, n=22). Visual analogue scale (VAS) scores of neck and arm pain, modified Oswestry Disability Index (mODI) score, and radiological results including cervical range of motion (ROM) were assessed before and after surgery. RESULTS: VAS and mean mODI scores decreased after surgery from 5.1 and 57.6 to 2.7 and 31.5 in group A and from 6.1 and 59.9 to 3.7 and 38.4 in group B, respectively. In both groups, VAS and mODI scores significantly improved postoperatively (p<0.001), although no significant intergroup differences were found. Also, cervical dynamic ROM was preserved or gradually improved up to 18 months after cervical arthroplasty in both groups. Global, segmental and adjacent ROM was similar for both groups during follow-up. No cases of device subsidence or extrusion were recorded. CONCLUSION: Clinical and radiological results following cervical arthroplasty in patients with severe degenerative cervical disc disease were no different from those in patients with mild degenerative cervical disc disease after 18 months of follow-up.

Lipoma arborescens associated with osseous/chondroid differentiation in subdeltoid bursa.

Lipoma arborescens (LA) is a rare benign lesion of unknown etiology. It is characterized histologically by villous proliferation of the synovial membrane and diffuse replacement of the subsynovial tissue by mature fat cells. This condition affects the knee joint most commonly. Cases involving other locations including glenohumeral joint,[1] hip,[2] elbow,[3] hand[4] and ankle[5] have been rarely described. Involvement of the subdeltoid bursa has also been reported, but to date no case has described LA with osseous/chondroid differentiation of this bursa. Another significant finding in our case was the coexistence of LA with intermuscular lipoma, SLAP lesion and labral cyst.

Primary osteosarcoma arising from the middle turbinate in a pediatric patient.

Osteosarcomas usually occur as secondary tumors after radiation therapy or chemotherapy. Without a history of irradiation to the head and neck area, primary osteosarcoma of the turbinate is extremely rare. We report here a rare case of primary turbinate osteosarcoma presenting as a relatively small, well-circumscribed, turbinate mass. Its appearance mimicked a benign nasal mass like mucocele and polyp. We also reviewed the previously reported cases of tumor arising from turbinate.

Muscular involvement of Behçet's disease: ultrasonography, computed tomography, and magnetic resonance imaging findings.

Behçet's disease (BD) is a form of systemic vasculitis with the classic triad of recurrent oral and genital ulcers along with uveitis. In BD, muscular involvement is very rare. We report a case of muscular involvement in BD with characteristic findings using ultrasonography, computed tomography, and magnetic resonance imaging.

Uncommon pulmonary metastasis presenting as pulmonary infarction with tumour emboli in two cases.

We report two cases of pathologically proven pulmonary metastases presenting as pulmonary infarction with tumour emboli. In two cases, high-resolution CT showed multiple small subpleural consolidations in both lungs. The patients had breast cancer and uterine cervix cancer, respectively. Although various pulmonary diseases show subpleural consolidations on CT, pulmonary metastases by tumour emboli should be primarily considered in differential diagnosis especially when the patient has known malignancy.

Pseudoaneurysm of the popliteal artery mimicking tumorous condition.

Diagnosing pseudoaneurysms of the popliteal artery is usually straightforward in physical examinations and imaging findings. However, when a pseudoaneurysm shows a soft tissue mass with adjacent osseous change, it can mimic a bone tumor or a soft tissue sarcoma. We present a case of a 65-year-old man who had a pseudoaneurysm of the popliteal artery showing soft tissue mass and insinuating into the intramedullary cavity of the tibia. This presented case emphasizes the importance of considering pseudoaneurysms in the differential diagnosis of an apparent soft tissue mass with pressure erosion in adjacent bone.

Ectopic hidradenoma papilliferum of the breast: ultrasound finding.

Hidradenoma papilliferum (HP) is a benign neoplasm arising from mammary-like glands which typically involves the dermal layer of the female anogenital area. The prognosis for HP is good. Recurrence is unusual and is typically attributed to incomplete excision of the primary tumor. Malignant transformation is rare and HP of the breast has not yet been reported. Ectopic HP is usually solitary, small, and asymptomatic. It appears as a well-circumscribed, complex cystic mass in the dermis on ultrasound. We present a case of HP arising from the axillary tail of the breast.

Myxoid chondrosarcoma of the sinonasal cavity in a child: a case report.

Chondrosarcomas are malignant tumors of cartilage that rarely involve the sinonasal region, and myxoid chondrosarcoma is a rare histologic variant of chondrosarcoma that usually occurs in the soft tissue of extremities. Although several case reports and results of small series of chondrosarcomas in the sinonasal region in children are available, myxoid type chondrosarcoma is extremely rare. We recently experienced a case of low grade myxoid chondrosarcoma involving the sinonasal cavity in a 10-year-old boy, and here we report its radiologic-pathologic findings. In this case, chondroid calcification on CT and septal and marginal enhancement on MRI suggested a chondrosarcoma. Whole body PET-CT demonstrated no definite metastatic lesion and a low peak standardized uptake value primary tumor. However, no definite distinguishing imaging features were observed that distinguished low grade myxoid chondrosarcoma from conventional chondrosarcoma.