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To develop a multi-radionuclide imaging system with a flexible and compact structure that has a potential for breast and other applications, and to evaluate its performances under both positron emission tomography and single photon emission imaging conditions. The plane detector was composed of 5 × 6 blocks with an effective detection area of 168.6 mm × 202.4 mm. Each block consisted of a 16 × 16 LYSO array. The pixel size is 1.9 mm × 1.9 mm × 15 mm. An 8 × 8 silicon photomultiplier (SiPM) array with SensL’s C-30035 sensors was coupled to the LYSO array, separated by a 1.5-mm-thick glass. To minimize the influence of temperature on the detector, the active part of the front-end electronics was kept away from SiPMs. Self-designed data acquisition system and reconstruction software were utilized to evaluate the performances of the whole system. All the blocks had excellent pixels identification. An average energy resolution of 11.39% for 511 keV and 21.37% for 140 keV was obtained. In the PET mode, the best spatial resolution was better than 2 mm and the system sensitivity reached up to 11.05% at 60 mm distance. In the single photon emission imaging mode, a spatial resolution better than 3 mm was obtained. The results indicated that the system has a good overall performance and can be used in breast imaging and other general PET applications. It also has the potential to be used for single photon emission imaging. In pursuit of a better spatial resolution of cross-plane, PSF and DOI technology will be developed in the next work. For specific applications, further improvement of the detector system such as performance evaluation with phantoms will be carried out.

Group A rotavirus (RV-A) genotypes isolated in Malaysia was studied to estimate the effectiveness of a universal RV-A vaccination in Malaysia. A simple mathematical model was used, with input from a two-year, two-center, prospective study on hospitalization of RV-A gastroenteritis (RVGE) in young children, published data on RV-A hospitalizations and genotypes, mortality on childhood GE and published genotype-specific efficacy data on two RV-A vaccines. Assuming a 95% vaccine coverage, the overall projected effectiveness was 75.7 to 88.1% for Rotateq® and 78.7 to 90.6% for Rotarix® against RVGE-related hospitalizations. The projected annual reduction in RVGE-related deaths was 27 to 32 deaths (from 34 deaths) for Rotateq® and 28 to 32 deaths annually forRotarix®. A universal RV-A vaccine is efficacious in reducing RVGE-related hospitalizations and mortality in Malaysia.

OBJECTIVE: The central nervous system (CNS) is often affected by systemic lupus erythematosus (SLE), but assessment of CNS outcomes using noninvasive cerebral structural measures remains in its infancy. Magnetic resonance imaging (MRI) with expert visual interpretation is critical to diagnosis, but does not permit quantitative measurements. Our pilot study investigated whether quantitative brain volumetric analyses could be used to detect white-matter (WM) abnormalities and responses to treatment in SLE (ClinicalTrials.gov: NCT00703742). METHODS: Forty-two pairs of SLE patients and healthy controls underwent high-resolution 3-dimensional structural MRI scans. Combining voxel-based morphometry and region of interest analyses, subtle WM volume abnormalities in whole brains from SLE patients were identified, and regional WM volume was calculated. Associations between WM volume and symptom severity, as well as the effects of immunosuppressive therapy, were then investigated. RESULTS: The WM volume of the SLE group was significantly decreased in the bilateral posterior and anterior crus of the internal capsule (PIC and AIC, respectively), the subgyral right frontal lobe, and left temporal lobe (p < 0.001). Regional WM volume (left PIC and right AIC) was correlated with SLEDAI scores. The WM volume of patients treated with immunosuppressive therapy was greater than that of patients who were never treated with immunosuppressive therapy. CONCLUSION: Quantitative brain volumetric analyses detect brain injuries in WM for SLE that are not obvious by conventional MRI, and may be adequately sensitive and quantitative to measure the effect of therapeutic interventions in preventing brain injury and outcomes in SLE.

Graft rejection and disease recurrence are well-recognized complications of liver transplantation (LT) for autoimmune hepatitis (AIH) and autoimmune sclerosing cholangitis (AISC). We describe indications and outcome of LT for childhood AIH and AISC.

Graft rejection and disease recurrence are well‐recognized complications of liver transplantation (LT) for autoimmune hepatitis (AIH) and autoimmune sclerosing cholangitis (AISC). We describe indications and outcome of LT for childhood AIH and AISC. Twenty‐year retrospective review of a cohort of children (n = 101) with AIH, AISC, or AIH/sclerosing cholangitis overlap syndrome from a single center. AIH type 1 (AIH1, n = 67) was more common than AIH type 2 (AIH2, n = 18), AISC (n = 8), or overlap syndrome (n = 8). Overall, 18 patients (18%) required LT, the indications being failure of medical therapy (n = 16) and fulminant liver failure (n = 2). Patients with AIH who required LT had a more prolonged prothrombin time at presentation compared with those who did not undergo transplantation (P= 0.01). Patients with AIH1 who received LT had a lower aspartate transaminase (P= 0.009) and alanine transaminase (P= 0.02) levels at initial diagnosis compared with those with AIH1 who did not undergo transplantation. Post‐LT, 11 patients (61%) had 18 episodes of rejection, most were steroid sensitive. Disease recurrence was observed in 7 patients (39%, median duration post‐LT 33 months), more common in AIH2 (80% recurrence rate), and those taking cyclosporine (71%, 5/7 patients) compared with those taking tacrolimus (18%, 2/11 patients; P< 0.05) and in 3 of 3 children who did not have maintenance steroids post‐LT. The overall 5‐ and 7‐year post‐LT survival rate was 94% and 88%, respectively. LT is a good therapeutic option for progressive AIH and AISC, although recurrence of the primary autoimmune process limits the outcome.