Fat-suppressed T2-weighted Magnetic Resonance Research Articles

Radiomic nomogram for predicting high-risk cytogenetic status in multiple myeloma based on fat-suppressed T2-weighted magnetic resonance imaging

Rationale and ObjectivesRadiomics has demonstrated potential in predicting the cytogenetic status of multiple myeloma (MM). However, the role of single-sequence radiomic nomograms in predicting the high-risk cytogenetic (HRC) status of MM remains underexplored. This study aims to develop and validate radiomic nomograms based on fat-suppressed T2-weighted images (T2WI-FS) for predicting MM’s HRC status, facilitating pre-treatment decision-making and prognostic assessment. Materials and methodsA cohort of 159 MM patients was included, comprising 71 HRC and 88 non-HRC cases. Regions of interest within the most significant tumor lesions on T2WI-FS images were manually delineated, yielding 1688 features. Fourteen radiomic features were selected using 10-fold cross-validation, employing methods such as variance thresholds, Student’s t-test, redundancy analysis, and least absolute shrinkage and selection operator (LASSO). Logistic regression was utilized to develop three prediction models: a clinical model (model 1), a T2WI-FS radiomic model (model 2), and a combined clinical-radiomic model (model 3). Receiver operating characteristic (ROC) curves evaluated and compared the diagnostic performance of these models. Kaplan-Meier survival analysis and log-rank tests assessed the prognostic value of the radiomic nomograms. ResultsModels 2 and 3 demonstrated significantly greater diagnostic efficacy compared to model 1 (p < 0.05). The areas under the ROC curve for models 1, 2, and 3 were as follows: training set—0.650, 0.832, and 0.846; validation set—0.702, 0.730, and 0.757, respectively. Kaplan-Meier survival analysis indicated comparable prognostic values between the radiomic nomogram and MM cytogenetic status, with log-rank test results (p < 0.05) and concordance indices of 0.651 and 0.659, respectively; z-score test results were not statistically significant (p = 0.153). Additionally, Kaplan-Meier analysis revealed that patients in the non-HRC group, low-RS group, and aged ≤ 60 years exhibited the longest overall survival, while those in the HRC group, high-RS group, and aged > 60 years demonstrated the shortest overall survival (p = 0.004, Log-rank test). ConclusionsRadiomic nomograms are capable of predicting the HRC status in MM. The cytogenetic status, radiomics model Rad score, and age collectively influence the overall survival of MM patients. These factors potentially contribute to pre-treatment clinical decision-making and prognostic assessment.

Differentiation of parotid pleomorphic adenoma from Warthin tumor using signal intensity ratios on fat-suppressed T2-weighted magnetic resonance imaging

ObjectiveTo investigate the value of magnetic resonance imaging (MRI) signal intensity ratios (SIRs) based on fat-suppressed T2-weighted imaging (FS-T2WI), together with demographic features, MRI anatomical characteristics, and SIRs of histopathological patterns of the tumors, in the differentiation of parotid pleomorphic adenoma (PA) from Warthin tumor (WT). Study DesignIn total, 90 patients with PA and 56 patients with WT were enrolled in the study. SIRs of tumor to normal parotid gland (SIR-T/P), spinal cord (SIR-T/S), and muscle (SIR-T/M) were calculated. Demographic and MRI anatomical features of the two patient groups were compared with univariate analysis and multivariate logistic regression analysis. The area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were analyzed to evaluate the utility of SIRs in distinguishing between PA and WT. ResultsSIR-T/P exhibited outstanding discriminating ability (AUC=0.934), SIR-T/S had excellent discrimination (AUC=0.839), and SIR-T/M showed acceptable discrimination (AUC=0.728). When SIR-T/P of 1.96 was selected as the cutoff value, sensitivity and specificity were 0.756 and 0.982, respectively. SIR-T/P, age, sex, and number of lesions were identified as independent predictors by multivariate logistic regression analysis. Differences in SIRs between histopathological patterns were significant. ConclusionSIR-T/P based on FS-T2WI is an effective discriminator in the differential diagnosis between PA and WT. Age, sex, and number of lesions provided additional value in the differentiation.

Percutaneous Sclerotherapy of Large Venous Malformations Using Consecutive Polidocanol and Bleomycin Foam: MR Imaging Volumetric and Quality-of-Life Assessment

PurposeTo retrospectively evaluate sclerotherapy using consecutive polidocanol and bleomycin foam (CPBF) for large untreated venous malformations (VMs) and/or those resistant to prior treatment. Materials and MethodsThis retrospective study included all patients treated with CPBF for untreated VMs larger than 10 mL and/or refractory to treatment between May 2016 and October 2019. Baseline and follow-up VM volumes were measured on fat-suppressed T2-weighted magnetic resonance (MR) imaging. Outcome was evaluated on postprocedural MR imaging volumetry and by a retrospective survey assessing clinical response and adverse events. Imaging response was considered good for volume reduction from 50% to 70% and excellent for volume reduction ≥70%. Symptoms and quality-of-life (QoL) scores were compared before and after CPBF sclerotherapy. ResultsForty-five patients (mean age, 16 years; range, 1–63 years; 25 males) with 57 VMs were analyzed and treated by 80 sclerotherapy. Sixty percent (27 of 45) of patients had undergone prior treatment for VM. Median VM volume was 36.7 mL (interquartile range, 84 mL) on pretherapy MR imaging. Good and excellent results after the last sclerotherapy were achieved in 36% (16 of 45) and 29% (13 of 45) of patients, respectively, corresponding to a decrease of >50% in 60% (34 of 57) of VMs. QoL score increased by at least 3 points, regardless of initial symptoms. Most patients did not desire additional sclerotherapy owing to near complete symptomatic relief, even for patients who did not achieve a good response. Swelling, pain, and motor impairment scores significantly improved after CPBF. Adverse events included fever (44%, 15 of 34) and nausea/vomiting (29%, 10 of 34). ConclusionsCPBF sclerotherapy represents an effective therapy for large and/or refractory VMs with minimal adverse events.

Spinal Cerebrospinal Fluid Leak: Current Concepts and Management Policies

In this article we provide an update on the recent developments in understanding the diagnosis and treatment of spinal cerebrospinal fluid(CSF)leaks. Patients with spinal CSF leak show an increasingly broad spectrum of clinical presentations including intractable whiplash-associated disorder(WAD)and orthostatic dysregulation in childhood, in addition to classical spontaneous intracranial hypotension(SIH). A simple understanding of the condition defined by the presence of low CSF pressure is no longer sufficient or accurate. Fat-suppressed T2-weighted magnetic resonance images and continuous epidural fluid infusion as a diagnostic therapy ensure accurate diagnosis. Accurate localization of the leak followed by targeted epidural blood patch(EBP)significantly improves the outcome of patients with spinal CSF leak. In addition to the known sites of CSF leakage, a newly identified CSF leak site, at the craniovertebral junction dural entry point of the vertebral artery(VA), is described.

Texture Analysis of Fat-Suppressed T2-Weighted Magnetic Resonance Imaging and Use of Machine Learning to Discriminate Nasal and Paranasal Sinus Small Round Malignant Cell Tumors.

ObjectiveWe used texture analysis and machine learning (ML) to classify small round cell malignant tumors (SRCMTs) and Non-SRCMTs of nasal and paranasal sinus on fat-suppressed T2 weighted imaging (Fs-T2WI).MaterialsPreoperative MRI scans of 164 patients from 1 January 2018 to 1 January 2021 diagnosed with SRCMTs and Non-SRCMTs were included in this study. A total of 271 features were extracted from each regions of interest. Datasets were randomly divided into two sets, including a training set (∼70%) and a test set (∼30%). The Pearson correlation coefficient (PCC) and principal component analysis (PCA) methods were performed to reduce dimensions, and the Analysis of Variance (ANOVA), Kruskal-Wallis (KW), and Recursive Feature Elimination (RFE) and Relief were performed for feature selections. Classifications were performed using 10 ML classifiers. Results were evaluated using a leave one out cross-validation analysis.ResultsWe compared the AUC of all pipelines on the validation dataset with FeAture Explorer (FAE) software. The pipeline using a PCC dimension reduction, relief feature selection, and gaussian process (GP) classifier yielded the highest area under the curve (AUC) using 15 features. When the “one-standard error” rule was used, FAE also produced a simpler model with 13 features, including S(5,-5)SumAverg, S(3,0)InvDfMom, Skewness, WavEnHL_s-3, Horzl_GlevNonU, Horzl_RLNonUni, 135dr_GlevNonU, WavEnLL_s-3, Teta4, Teta2, S(5,5)DifVarnc, Perc.01%, and WavEnLH_s-2. The AUCs of the training/validation/test datasets were 1.000/0.965/0.979, and the accuracies, sensitivities, and specificities were 0.890, 0.880, and 0.920, respectively. The best algorithm was GP whose AUCs of the training/validation/test datasets by the two-dimensional reduction methods and four feature selection methods were greater than approximately 0.800. Especially, the AUCs of different datasets were greater than approximately 0.900 using the PCC, RFE/Relief, and GP algorithms.ConclusionsWe demonstrated the feasibility of combining artificial intelligence and the radiomics from Fs-T2WI to differentially diagnose SRCMTs and Non-SRCMTs. This non-invasive approach could be very promising in clinical oncology.

Microsurgical Anatomy of the Inferior Petroclival Vein and its Relation to Surrounding Structures: A Cadaveric and Radiological Study.

The inferior petroclival vein (IPV) courses along the extracranial surface of the petroclival fissure. It is occasionally involved in vascular diseases and has recently been used for vascular access to the cavernous sinus. However, detailed descriptions of its anatomy are currently lacking. To define the anatomic relationship between the IPV and its surrounding structures based on cadaveric dissection and radiological analysis. A dry skull and an injected cadaver head were examined to reveal the relationships between the IPV and its surrounding structures. The existence of the IPV and its relationships with other venous structures were also examined by contrast-enhanced, fat-suppressed T1-weighted magnetic resonance imaging in 26 patients (51 sides). The entire course of the IPV was shown via stepwise cadaver dissection from below. Its relationships with surrounding structures, such as the jugular bulb, sigmoid sinus, inferior petrosal sinus, petrosal venous confluence, and the posterior, lateral, and anterior condylar veins, were also shown. In the radiological analysis, the IPV was identified on all sides. The rostral end of the vein was connected to the venous plexus around the carotid artery on all sides. The vein drained into the caudal end of the inferior petrosal sinus (49/51 sides, 96.1%) or into the anterior condylar vein (2/51 sides, 3.9%). A precise understanding of the anatomy of the IPV will enable endovascular and skull base surgeons to achieve diagnoses and gain safe access to lesions involving the IPV.

Quantification of Lumbar Spinal Canal Stenosis by Quantitative Fat-Suppressed Contrast-Enhanced Magnetic Resonance Imaging.

Fat-suppressed T1-weighted magnetic resonance images (MRIs) enhanced with gadolinium can evaluate the internal vertebral venous plexus and cauda equina. This study compared such findings with clinical situations and discusses whether these are helpful for symptomatic grading and selection at the surgical level in patients with lumbar central stenosis. A total of 263 patients (337 levels < 75 mm2 of dural cross sectional area (DCSA)) were included. The enhancement patterns of dorsal epidural vein (DVCE), periradicular vein (PVCE) and intraradicular vein (IRCE) were assessed qualitatively. The quantification of IRCE was acquired by the ratio (%) (enhancement parameters: MS/P1, MS/P2, WR/P1, WR/P2) of signal intensities between the cauda equina (MS-IRCE: maximal spot rootlet, WR-IRCE: whole rootlets) and psoas muscle (P1, P2). Receiver-operator characteristic curves were plotted to obtain imaginary cutoff values for the prediction of symptomatic appearance or operation decision. All levels were classified into seven groups on the basis of pain distribution and the presence of IRCE. PVCE was significantly related to high incidences of symptoms, unilaterality and operation. DVCE and IRCE were connected with high incidences of symptoms, bilaterality and operation. IRCE was also related to high visual analogue scale (VAS), small DCSA and high enhancement parameters. The order of the group was concordant with the degree of enhancement parameters (p = 0.000). Cutoff values of enhancement parameters for prediction were as follows: symptoms (147/123/140/121), bilaterality (165/139/157/137) and operation (164/139/159/138). Enhancement patterns and parameters could help in stratification, grading and decision-making at the surgical level.

Radiological imaging features of the salivary glands in xerostomia induced by an immune checkpoint inhibitor

The clinical features of xerostomia induced by immune checkpoint inhibitors (ICI) are similar to those of Sjögren’s syndrome (SS), whereas the immunohistological and serological features are known to differ from those of SS. However, the radiologic imaging features of salivary glands are not yet well known. We report a case of a 56-year-old male patient diagnosed with ICI-induced xerostomia. The patient underwent various imaging examinations to investigate the condition of the salivary glands, which indicated the following: (1) less specific findings on contrast-enhanced computed tomography, (2) mixed with intermediate and low signal intensity on both T1-weighted and fat-suppressed T2-weighted magnetic resonance imaging and poor “salt and pepper” appearance on magnetic resonance sialography, and (3) multiple ovoid hypoechoic areas with hyperechoic bands without acute sialadenitis on ultrasound. These radiologic imaging findings suggested remarkable lymphocyte infiltration, which could be a characteristic of ICI-induced xerostomia.

Effectiveness of the periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) technique for reducing motion artifacts caused by mandibular movements on fat-suppressed T2-weighted magnetic resonance (MR) images

PurposeTo compare a fat-suppressed T2-weighted periodically rotated overlapping parallel lines with enhanced reconstruction (T2W-PROPELLER) sequence with a fat-suppressed T2-weighted fast spin-echo (T2W-FSE) sequence in the oral and maxillofacial regions for the evaluation of the presence of motion artifacts caused by mandibular movements. MethodsFifty-six healthy adult volunteers were examined in a closed mouth position and then with three different rhythmical mandibular movements throughout MR scanning: open-close movement (movement 1), lateral movement (movement 2) and open-close and lateral movement (movement 3). All subjects were scanned first with fat-suppressed T2W-FSE and then with fat-suppressed T2W-PROPELLER while performing the same movements. Motion artifacts, including ghosting or pulsation artifacts, streak artifacts, susceptibility artifacts and the overall image quality were independently evaluated by two oral and maxillofacial radiologists using a five-point scale. The score graded by the two observers was averaged. ResultsThe inter-observer agreement was almost perfect for all evaluated items (κ ≥ 0.81). The T2W-PROPELLER images showed significantly fewer ghosting artifacts than T2W-FSE images in subjects performing the mandibular movements throughout MR scanning (P < .001). T2W-PROPELLER images also showed significantly fewer pulsation artifacts than T2W-FSE images, regardless of the performance of a movement, throughout MR scanning (P < .001). Finally, the T2W-PROPELLER images showed a significantly better overall image quality than T2W-FSE images in subjects performing movements 2 or 3 throughout MR scanning (P < .001). ConclusionThe PROPELLER technique was found to be effective in reducing the motion artifacts caused by mandibular movements on fat-suppressed T2W MR images in the oral and maxillofacial regions.

Orbital Interstitial Fluid: Evidence of a Potential Pathway for Extracranial Cerebrospinal Fluid Absorption.

The aim of the study was to describe the prevalence and characteristics of orbital interstitial fluid seen on magnetic resonance (MR) images of infants and young children. Fat-suppressed axial T2-weighted MR images of 100 consecutive infants and young children (<6 years) without orbital pathology were retrospectively reviewed by 2 neuroradiologists. The presence, location, and extent of high-signal orbital interstitial fluid were characterized and tabulated as a function of age. Orbital interstitial fluid was detected in 90 (90%) of the 100 subjects overall, present in 100% (75/75) of infants and children younger than 3 years, 75% (12/16) of those aged 3 to 5 years, and 33% (3/9) of those aged 5 to 6 years. The fluid was bilateral and symmetric in all cases. Two morphologic patterns were distinguished, which often co-existed: (1) a focal discrete curvilinear band of fluid in the posterior-lateral orbit, more common in younger patients, and (2) an ill-defined, lace-like pattern primarily in the superior orbit seen in subjects of all ages. Orbital interstitial fluid as detected by fat-suppressed T2-weighted MR imaging is a nearly universal finding in infants and young children and should not be considered pathologic. It may have either a focal or lace-like pattern or both. Orbital interstitial fluid decreases in size and prevalence as a function of age but is still present in nearly half of children aged 4 to 6 years. Possible explanations concerning the nature and origin of this fluid are presented, including the fascinating possibility that the fluid represents an extracranial pathway for outflow of cerebrospinal fluid.

Periportal lymphatic system on post-hepatobiliary phase Gd-EOB-DTPA-enhanced MR imaging in normal subjects and patients with chronic hepatitis C.

We sought to evaluate visualization of periportal lymphatics and lymph nodes (lymphatic system) on Gd-EOB-DTPA-enhanced magnetic resonance (MR) images using a fat-suppressed T2-weighted sequence with 3-dimensional (3D) volume isotropic turbo spin echo acquisition (VISTA) at 3.0 T in normal subjects and patients with chronic hepatitis C. MR imaging was performed in 254 subjects between June 2013 and May 2016. After applying inclusion and exclusion criteria, the final population was 31 normal subjects and 34 patients with chronic hepatitis C. Images were acquired after the hepatobiliary phase following intravenous administration of Gd-EOB-DTPA, which causes signal loss in the bile ducts, to facilitate the visualization of the periportal lymphatic system. Two radiologists assessed the visualization of the periportal lymphatic system in 31 normal subjects. The axial dimensions of the main periportal lymphatic system in normal subjects were measured and compared with those of 34 patients with chronic hepatitis C using the Mann-Whitney U-test, and their correlation with a hepatic fibrosis marker, the Fibrosis-4 (FIB-4), was assessed using Spearman's rank correlation test. The periportal lymphatic system was detected as high signal intensity areas surrounding the portal vein up to the third branches by each reader in all normal subjects. The axial dimensions of the main periportal lymphatic system in patients with chronic hepatitis C were significantly larger than those in normal subjects (p<0.0001), and showed a significantly positive correlation with the FIB-4 score (ρ=0.73, p<0.001). Fat-suppressed T2-weighted MR imaging with 3D-VISTA acquired after the hepatobiliary phase on Gd-EOB-DTPA-enhanced imaging may be a useful noninvasive method for evaluating the periportal lymphatic system and the degree of hepatic fibrosis.

Postmortem Study of Validation of Low Signal on Fat-Suppressed T1-Weighted Magnetic Resonance Imaging as Marker of Lipid Core in Middle Cerebral Artery Atherosclerosis.

Background and Purpose—High signal on T1-weighted fat-suppressed images in middle cerebral artery plaques on ex vivo magnetic resonance imaging was verified to be intraplaque hemorrhage histologically. However, the underlying plaque component of low signal on T1-weighted fat-suppressed images (LST1) has never been explored. Based on our experience, we hypothesized that LST1 might indicate the presence of lipid core within intracranial plaques.Methods—1.5 T magnetic resonance imaging was performed in the postmortem brains to scan the cross sections of bilateral middle cerebral arteries. Then middle cerebral artery specimens were removed for histology processing. LST1 presence was identified on magnetic resonance images, and lipid core areas were measured on the corresponding histology sections.Results—Total 76 middle cerebral artery locations were included for analysis. LST1 showed a high specificity (96.9%; 95% confidence interval, 82.0%–99.8%) but a low sensitivity (38.6%; 95% confidence interval, 24.7%–54.5%) for detecting lipid core of all areas. However, the sensitivity increased markedly (81.2%; 95% confidence interval, 53.7%–95.0%) when only lipid cores of area ≥0.80 mm2 were included. Mean lipid core area was 5× larger in those with presence of LST1 than in those without (1.63±1.18 mm2 versus 0.32±0.31 mm2; P=0.003).Conclusions—LST1 is a promising imaging biomarker of identifying intraplaque lipid core, which may be useful to distinguish intracranial atherosclerotic disease from other intracranial vasculopathies and to assess plaque vulnerability for risk stratification of patients with intracranial atherosclerotic disease. In vivo clinical studies are required to explore the correlation between LST1 and clinical outcomes of patients with intracranial atherosclerotic disease.

Perineural Spread in Noncutaneous Head and Neck Cancer: New Insights into an Old Problem.

Head and neck malignancies have the propensity to invade nerves. Perineural tumor invasion is common, with some series reporting rates of 30 to 100%. Squamous cell carcinoma and adenoid cystic carcinoma are the most commonly involved tumors. The most commonly involved nerves are the trigeminal (cranial nerve [CN] V) and facial (CN VII) and their branches. Neural spread away from a tumor is encountered less often and usually causes specific symptoms such as pain, muscle weakness, and atrophy, depending on the involved nerves. While clinical symptoms and physical examination may suggest the presence of neural invasion, specific imaging modalities such as fat-suppressed T1-weighted magnetic resonance images, should be utilized to identify perineural tumor spread in its early phases. Perineural tumor spread should be considered and addressed in the treatment planning of patients with head and neck or skull base cancers as it can influence the extent of surgery, and the dosage and fields of radiation therapy. In the current review, we discuss the clinical course of perineural tumor spread and its therapeutic implications.

Feasibility of fat-saturated T2-weighted magnetic resonance imaging with slice encoding for metal artifact correction (SEMAC) at 3T

Background and PurposeFluid-sensitive MR imaging in postoperative evaluation is important, however, metallic artifacts is inevitable. The purpose is to investigate the feasibility of fat-saturated slice encoding for metal artifact correction (SEMAC)-corrected T2-weighted magnetic resonance (MR) at 3T in patients with spinal prostheses. MethodsFollowing institutional review board approval, 27 SEMAC-encoded spinal MRs between September 2012 and October 2013 in patients with spinal metallic prostheses were analyzed. The MR images were scanned on a 3T MR system including SEMAC-corrected and uncorrected fast spin echo (FSE) T2-weighted MR images with fat-saturation. Two musculoskeletal radiologists compared the image sets and qualitatively analyzed the images using a five-point scale in terms of artifact reduction around the prosthesis, visualization of the prosthesis and pedicle, and intervertebral neural foramina. Quantitative assessments were performed by calculating the ratio of signal intensity from the fixated vertebra and that from upper level vertebra. For statistical analyses, paired t-test was used. ResultsFat-saturated SEMAC-corrected T2-weighted MR images enabled significantly improved metallic artifact reduction (P<0.05). Quantitative evaluation of the signal intensity ratio of screw-fixated vertebra and upper level vertebra showed a significantly lower ratio on fat-saturated SEMAC images (P<0.05), however, the high signal intensity of signal pile-up could be not completely corrected. ConclusionSEMAC correction in fat-suppressed T2-weighted MR images can overcome the signal loss of metallic artifacts and provide improved delineation of the pedicle screw and peri-prosthetic region. Signal pile-up, however, could not be corrected completely, therefore readers should be cautious in the evaluation of marrow around the prosthesis.

Cervical spine fracture in advanced ankylosing spondylitis

A 51-year-old man with a 22-year history of ankylosing spondylitis who had been treated with nonsteroidal anti-inflammatory drugs and infliximab presented with severe posterior neck pain, which had been aggravated after he fell backwards 3 months earlier. The neurological examination was normal. Plain radiographs showed total ankylosis of the cervical spine and a C5 vertebral body fracture with anterior dislocation of C4 on C5 (Fig. 1). There were numerous thin pieces of foreign material along the spine (Fig. 1). The patient said he had undergone Korean traditional gold thread acupuncture therapy, which had not been effective. Gadolinium-enhanced fat-suppressed T1-weighted magnetic resonance imaging showed a recent compression fracture of the C5 vertebral body and resultant spinal cord compression (Fig. 2), as well as an old compression fracture of C7. For cervical spine fractures in ankylosing spondylitis, conservative treatment with gentle low-weight cervical traction can be performed initially, in the absence of a neurologic deficit. However, secondary neurological deterioration occurs frequently due to the delayed dislocation at the original fracture site, and surgical treatment is generally recommended. On surgical exploration of our patient, the C5 fracture was found to be stable and surgical f ixation was not done. The cervical spine is the most frequent site of acute spinal fracture in ankylosing spondylitis, particularly at C5-6 and C6-7. Since the cervical fractures in ankylosing spondylitis are usually unstable, with a high risk of neurological deficits, our patient was lucky not to have had any significant neurological complications. Figure 1 Plain radiograph shows total ankylosis of the cervical spine, a C5 vertebral body fracture with anterior dislocation of C4 on C5 (arrow), and numerous thin foreign bodies along the spine. Figure 2 Gadolinium-enhanced fat-suppressed T1-weighted magnetic resonance image shows a recent compression fracture of the C5 vertebral body (arrow) and resultant spinal cord compression, as well as an old compression fracture of C7.

Subdeltoid Lipoma Arborescens Combined With Rotator Cuff Tears

Lipoma arborescens, a rare benign intra-articular lesion, is characterized by lipomatous proliferation of the synovium in which the subsynovial tissue is replaced by mature adipocytes. Subdeltoid bursa is a rare location for lipoma arborescens, and only a few cases have been reported in the literature. This article reports 2 cases of subdeltoid lipoma arborescens combined with rotator cuff tears, and the possible relationships between subdeltoid lipoma arborescens and rotator cuff tears are discussed. The intra-articular villous proliferations on fat-suppressed T2-weighted magnetic resonance imaging appeared as yellowish-white lipomatous villous proliferations on arthroscopy, and finger-like lipomatous proliferation of the synovium, where the subsynovial connective tissue is replaced by mature adipocytes, on histology. Although further evidence would be necessary, the bony proliferations, in addition to bone-to-bone abrasion and inflammatory processes, may contribute to the relationship between subdeltoid lipoma arborescens and rotator cuff tears. Because this is a rare disease in a rare location, no established treatment guidelines are available for lipoma arborescens in subdeltoid bursa. For the current patients, arthroscopic excision of the lipoma arborescens and concomitant rotator cuff repair were prescribed after more than 6 months of conservative management. All patients had symptom relief and were satisfied with their results. Paying special attention to the radiologic and arthroscopic characteristics of the lipoma arborescens will help physicians and surgeons to achieve a more accurate diagnosis and effective treatment strategy, especially in patients with concomitant rotator cuff tears.

Intraosseous leiomyosarcoma arising in the epiphysis of the distal femur

Herein, we present a rare case of intraosseous leiomyosarcoma arising in the epiphysis of the distal femur and showing unusual radiographic features. A 44-year-old man presented with a pain in the left knee joint. Computed tomography revealed an intraosseous lesion with slightly increased attenuation and a thin marginal sclerotic rim in the femoral medial condyle. The signal of the lesion was hypointense on T1-weighted magnetic resonance (MR) images and hyperintense on fat-suppressed T2-weighted MR images. After gadolinium administration, the signal of the lesion was moderately and diffusely enhanced. The histological diagnosis of leiomyosarcoma was made based on a preoperative core biopsy specimen. Microscopic examination of the resected specimen revealed an ill-defined intraosseous tumor composed of proliferated atypical and mildly pleomorphic smooth muscle cells permeating among the bone trabeculae with only focal destruction of the bone trabeculae and low mitotic activity, indicating low grade leiomyosarcoma. The bone trabeculae at the periphery of the tumor were mildly thickened and anastomosed with a rim of an increased number of osteoblasts. Systemic examination showed no tumorous lesions in other anatomical sites. Leiomyosarcomas rarely present in the bone as a diffuse intertrabecular growth, even in low grade tumors.

The iliac wing sign: An indicator of the presence of bone and/or soft-tissue injury of the pelvis and hips

PurposeTo prospectively evaluate the feasibility of using the “iliac wing sign (IWS)” as an indicator of bone and/or soft-tissue injury of the pelvis and hips on magnetic resonance (MR) imaging. IWS means edema of the iliacus muscle attachment entering the iliac wing that is visualized as a linear high signal intensity on fat-suppressed T2-weighted MR images. MethodsConsecutive 106 patients who complained of hip pain were enrolled in this study. We evaluated the correlation between IWS and bone and/or soft-tissue injury of the pelvis and hips using Fisher's exact test. Further, performance parameters of sensitivity, specificity, accuracy, the positive predictive value (PPV), and negative predictive value (NPV) of IWS were calculated. ResultsThirty-eight of the 106 (36%) patients had bone and/or soft-tissue injury. Twenty-seven of these 38 (71%) patients with injury showed a positive IWS, while only 11 of 68 (16%) patients without injury showed a positive IWS (p<.0001). IWS, thus, yielded a sensitivity of 71%, specificity of 84%, accuracy of 79%, positive predictive value (PPV) of 71%, and negative predictive value (NPV) of 84%. ConclusionIn cases with a positive IWS, the careful interpretation of MR images is needed because injury presence is highly likely, as suggested by the relatively high sensitivity and PPV. IWS absence may mean a low probability of injury because of the high specificity and NPV.

Can Necrotizing Infectious Fasciitis Be Differentiated from Nonnecrotizing Infectious Fasciitis with MR Imaging?

To retrospectively evaluate whether magnetic resonance (MR) imaging findings can be used to differentiate necrotizing infectious fasciitis (NIF) from nonnecrotizing infectious fasciitis (non-NIF). Institutional review board approval was obtained, but patient consent was not required for this retrospective review of records and images because patient anonymity was preserved. Thirty patients (seven with NIF, 23 with non-NIF) were included in the study. The following imaging findings were analyzed on fat-suppressed T2-weighted MR images: (a) signal intensity in the deep fascia (low, high, or mixed high and low), (b) thickness of abnormal signal intensity in the deep fascia (≥3 mm or <3 mm), (c) pattern of abnormal signal intensity in muscle (no abnormality, peripheral bandlike signal intensity, or patchy high signal intensity), (d) degree of deep fascia involvement (partial or extensive), and (e) degree of compartment involvement (fewer than three compartments or three or more compartments). On contrast material-enhanced fat-suppressed T1-weighted images, the contrast enhancement patterns of the abnormal deep fascia (no enhancement, enhancement, or enhancement with nonenhancing portion) and the muscle (no abnormality, peripheral bandlike signal intensity, or patchy high signal intensity) were evaluated. The presence of abscesses in the subcutaneous fat layer was evaluated with all sequences. The patients with NIF had a significantly greater frequency of (a) thick (≥3 mm) abnormal signal intensity on fat-suppressed T2-weighted images, (b) low signal intensity in the deep fascia on fat-suppressed T2-weighted images, (c) a focal or diffuse nonenhancing portion in the area of abnormal signal intensity in the deep fascia, (d) extensive involvement of the deep fascia, and (e) involvement of three or more compartments in one extremity (P < .05). MR imaging is potentially helpful for differentiating NIF from non-NIF. http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101164/-/DC1.

High-dose steroid therapy for idiopathic optic perineuritis: a case series

IntroductionIt has been reported that the prognosis of optic perineuritis may be poor when initiation of treatment is delayed. Here we report the successful treatment of three patients with idiopathic optic perineuritis, including two in whom initiation of therapy was delayed.Case presentationThree Japanese patients (two women aged 73 and 66 years, and one man aged 27 years) presented with loss of vision (for five months, several months, and two months respectively) and pain on eye movement in the third case only, and were diagnosed as having idiopathic optic perineuritis. Fat-suppressed T2-weighted magnetic resonance images showed high signal intensity areas around the affected optic nerves, suggesting the presence of optic perineuritis. Two patients received steroid pulse therapy and the third was given high-dose steroid therapy. The visual acuity improved in all three cases.ConclusionHigh-dose steroid therapy may be effective for idiopathic perineuritis in patients without optic nerve atrophy, even if initial treatment (including moderate-dose steroids) has failed.