Postoperative versus Spontaneous Intracranial Abscess: Diagnostic Value of the Apparent Diffusion Coefficient for Accurate Assessment.

Purpose To assess the diagnostic value of apparent diffusion coefficients (ADCs) in spontaneous intracranial abscesses compared with those occurring after primary neurosurgery. Materials and Methods This retrospective comparative study was approved by the local institutional review board. The requirement to obtain written informed consent was waived. A total of 73 consecutive patients who underwent preoperative diffusion-weighted magnetic resonance (MR) imaging from February 2005 to May 2015 were divided into two cohorts depending on whether the abscess was identified after a primary neurosurgical procedure (n = 43) or was a spontaneous abscess (n = 30). Abscesses were assessed for ADC by two readers independently. ADCs were described as medians with interquartile range. The Mann-Whitney and χ(2) tests were used to compare ADCs between the two cohorts, and χ(2) automatic interaction detection analysis was used to classify the ADCs into categories according to the cohorts. Results The median ADC of postoperative abscesses was 1.34 × 10(-3) mm(2)/sec (interquartile range, 1.00-1.62 × 10(-3) mm(2)/sec), which was significantly higher than the median ADC of spontaneous abscesses, 0.68 × 10(-3) mm(2)/sec (interquartile range, 0.58-0.79 × 10(-3) mm(2)/sec; P < .001). Twenty four (83%) of the abscesses with ADCs less than 0.79 × 10(-3) mm(2)/sec were found to be spontaneous, while only six (27%) abscesses with ADCs between 0.79 and 1.33 × 10(-3) mm(2)/sec and no abscesses with ADCs greater than 1.33 × 10(-3) mm(2)/sec were spontaneous (P < .001). Conclusion Significantly higher ADCs were found in postoperative abscesses compared with those in spontaneous abscesses. Diffusion-weighted imaging with ADC mapping is not sufficient for excluding postoperative intracranial abscess and should not be used as the key diagnostic modality in this situation. (©) RSNA, 2016.

Venous Malformations Sclerotherapy: Outcomes, Patient Satisfaction and Predictors of Treatment Success.

PURPOSE: To retrospectively evaluate the results of sclerotherapy for venous malformations, with emphasis on patient satisfaction, complications and predictors of positive response to treatment. MATERIALS AND METHODS: Three hundred and nine patients were treated with ethanol sclerotherapy for venous malformations in our center between the years 2000 and 2014. All of them were sent a self-assessment questionnaire for evaluation of their satisfaction and treatment complications. In total, 153 patients (mean age 21, range 6 weeks to 67 years) responded to the questionnaire. We analyzed clinical and imaging data from the medical records of these patients. RESULTS: Sixty-four (42%) patients had venous malformations in the lower extremities, 35 (23%) in head and neck regions, 33 (22%) in the trunk, 14 (9%) in the upper extremities and 5 (3%) in the buttock and genitalia. Complete relief of swelling, pain, functional and esthetic complaints was reported in 23%, 22%, 17% and 12% of patients, respectively. Thirty-eight (25%) patients reported being very satisfied with treatment outcomes, 55 (36%) were satisfied, 49 (32%) were not satisfied and 11 (7%) were very unsatisfied. We did not find significant correlations between patient satisfaction and demographics characteristics, lesion location, lesion size, tissue involvement or total sclerosant quantity. The rate of class 3 complications was 7% and that of class 4 complications was 2%. CONCLUSION: Ethanol sclerotherapy is an effective treatment for venous malformations. Nonetheless, this treatment has a significant complication rate. Patient satisfaction is independent of lesion characteristics and is not as high as may be expected.

Physiologic uptake of 18F-FDG in transposed ovaries may mimic metastasis on 18F-FDG PET/CT imaging.

BACKGROUND: Ovarian transposition is aimed at preserving ovarian function before irradiation in pelvic malignancies. The extrapelvic location of the ovaries and their physiologic fluorine-18-fluorodeoxyglucose (F-FDG)-uptake is a potential source of misdiagnosis as metastasis on F-FDG PET/CT. We describe the F-FDG PET/CT characteristics of transposed ovaries and their changes over time. PATIENTS AND METHODS: We reviewed F-FDG PET/CT studies of all consecutive women with pelvic malignancies who underwent ovarian transposition between 2007 and 2013. Studies were grouped according to the time period over which they were carried out. Findings were categorized by location, size, appearance (solid/mixed/cystic), presence of surgical clips, ovarian F-FDG uptake (maximum standardized uptake value), and attenuation values on CT (Hounsfield units). Group time-period differences were assessed. RESULTS: Seventy-nine F-FDG PET/CT studies were reviewed, 30 before and 49 after transposition. Time-period groups after transposition were up to 4 months (18 studies), 4.1-12 months (n=14), and more than 12 months (n=17). After transposition, ovaries were located mainly in the paracolic gutter (n=32) and subhepatic regions (n=18). Surgical clips were present in 67%. Both ovaries appeared more solid 1 year after surgery than preoperatively (13.7% before vs. 61.3% after surgery; P<0.001). Transient F-FDG-avidity was observed in 11 ovaries. Hounsfield unit values were higher within 4 months after surgery than preoperatively, reverting thereafter to preoperative values. CONCLUSION: After ovarian transposition, nonanatomic location, loss of cysts formation in favor of solid appearance over time, and intermittent F-FDG uptake of functioning transposed ovaries might mimic metastatic lesions. Careful interpretation of F-FDG PET/CT findings is mandatory in women with pelvic malignancies who have undergone ovarian transposition.

FDG PET-CT evaluation in neurolymphomatosis: imaging characteristics and clinical outcomes.

Neurolymphomatosis (NL) often represents unidentified non-Hodgkin lymphoma relapses. Considering its severity, early detection and treatment are crucial. We outline one hospital's 18F-FDG-PET-CT imaging findings of NL, along with the patients' clinical characteristics. Clinical records and imaging findings of 19 NL patients, PET-CT diagnosed, were retrospectively reviewed. Patient data, FDG-PET-CT findings and the presence of coexisting diseases, especially CNS involvement, were documented. Available MRI and clinical data verified the findings. All cases had increased linear FDG uptake along anatomic nerve sites. CTs showed varying degrees of corresponding soft-tissue-thickening. Clinical correlations also contributed to the diagnosis. In 4/19 patients, lymphoma presented with NL, in 15/19 it appeared with disease recurrence/progression. In 9/19, clinical symptoms suggested neural involvement while 10/19 had nonspecific symptoms. Eleven died of lymphoma within 0.9 years of diagnosis despite directed-therapy. Eight, however, survived up to 7.82 years post-diagnosis. Whole-body FDG-PET-CT can assist in early NL diagnosis, possibly enhancing survival.

A volcanic explosion of autoantibodies in systemic lupus erythematosus: a diversity of 180 different antibodies found in SLE patients.

Recent research in systemic lupus erythematosus (SLE) yielded new antigens and antibodies in SLE patients. We describe the various autoantibodies that can be detected in patients with SLE. A literature review, using the terms "autoantibody" and "systemic lupus erythematosus", was conducted to search for articles on autoantibodies in SLE, their target antigens, association with disease activity and other clinical manifestations. One hundred and eighty autoantibodies were so far described in SLE patients. These include autoantibodies that target nuclear antigens, cytoplasmic antigens, cell membrane antigens, phospholipid-associated antigens, blood cells, endothelial cells, and nervous system antigens, plasma proteins, matrix proteins, and miscellaneous antigens. The target of an autoantibody, the autoantigen properties, autoantibody frequencies in SLE, as well as clinical associations, and correlation with disease activity are described for all 180 autoantibodies. SLE is so far the autoimmune disease with the largest number of detectable autoantibodies. Their production could be antigen-driven, the result of a polyclonal B cell activation, impaired apoptotic pathways, or the outcome of an idiotypic network dysregulation.

Retropharyngeal and parapharyngeal abscess in children--epidemiology, clinical features and treatment.

OBJECTIVE: To describe the clinical presentation, diagnosis, management and complications of children with retropharyngeal abscesses (RPAs) and parapharyngeal abscesses (PPAs). METHODS: A retrospective chart review was conducted at two tertiary care, pediatric hospitals in Israel. The medical records of all children <18 years who had been admitted with a diagnosis of RPA or PPA during an 11-year period (January 1997 to February 2008) were reviewed. Data on demographics, presenting symptoms, physical examination findings, imaging studies and interpretation, laboratory results, hospital course, medical treatment and surgical interventions were retrieved. RESULTS: A total of 39 children were diagnosed as having RPA (n=26, 67%) or PPA (n=13, 33%). There was a predominance of boys (61.5%). The mean age of all the children at diagnosis was 4 years. The annual incidence increased over the 11-year period. The most common symptoms at presentation included fever (n=27, 70%) and neck pain (n=24, 62%). The physical examination revealed cervical lymphadenopathy in 30 children (77%), limitation of neck movements in 25 (64%), torticollis in 21 (54%), drooling in three (8%), and stridor in two (5%). Computerized tomographic (CT) scanning with contrast was performed in 37 patients (95%), of whom 17 underwent surgical drainage. Thirteen children were positively diagnosed as having an abscess by the finding of pus at surgery, of whom 12 had been found to have an abscess on their CT scan. All the patients received intravenous antibiotics. There was no significant difference in the duration of hospital stay between those who underwent surgery and those who were treated with antibiotics alone. There were no treatment failures and no complications in either of the two groups. CONCLUSION: Children with RPA most commonly present with restricted neck movements, fever and cervical lymphadenopathy, and rarely with respiratory distress or stridor. Many patients with RPA and PPA can be treated successfully without surgery. CT scans are helpful in diagnosing and assessing the extent of the infection, but they are not always accurate.