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.

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.

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.