Quality control performance evaluation of uMI550 digital PET-CT by utilising LYSO crystal natural radioactivity of 176Lu.

PURPOSE: Quality Control (QC) of the Positron Emission Tomography-Computed Tomography (PET-CT) system must be performed prior to the PET-CT acquisition to ensure the reproducibility as per the manufacturer recommendation. In this study we have evaluated the performance of daily PET QC test by utilising lutetium yttrium oxyorthosilicate (LYSO) scintillation crystal natural radioactivity of 176Lu as a source of radiation to perform the PET uCare.iQC with uMI550 digital PET-CT system. This was also compared with existing radioactive external source-based QC test with other manufacturer PET-CT systems. METHOD: This radioactive source free daily QC study was performed on uMI550 digital PET-CT system. The daily QC data report was captured and interpreted. This PET-CT system has unique feature that utilises the inherent property of LYSO crystal that is 176Lu with natural radioactivity abundance of 2.6%. The Lutetium-176 (176Lu) radioactivity is used to perform the daily QC in PET in place of external radioactive source of Germanium-68 (68Ge). This feature work automatically in preschedule manner to complete the daily QC at preset time in the morning and system get ready after the QC test. RESULTS: Over 120 automatic PET daily uCare.iQC test were performed. The daily PET QC test was prescheduling setup for 6:00 am in every morning. No failure on daily QC test were observed. The QC parameters and system parameters consistency was observed. CONCLUSION: It was concluded that the daily PET QC can be performed by utilising LYSO crystal inherent natural radioactivity of 176Lu as a source of radiation to perform the test as replacement of external 68Ge radioactive source. IMPLICATION FOR PRACTICE: PET-CT daily QC by utilizing the 176Lu radioactivity of LYSO crystal results in reducing the radiation exposure to operation staff and reducing operational cost by elimination 68Ge shield source Phantom.

Diagnosis of osteoarticular tuberculosis by immuno-PCR assay based on mycobacterial antigen 85 complex detection.

Diagnosis of osteoarticular tuberculosis (OATB) exhibits serious challenges owing to paucibacillary nature of specimens and localization of disease at sites that are difficult to access. We recently developed indirect immuno-PCR (I-PCR) and real-time I-PCR (RT-I-PCR) assays for the detection of mycobacterial antigen 85 complex (Ag85) in OATB patients. Detection limits for the purified Ag85 protein were found to be 1 and 41 fg ml-1 by I-PCR and RT-I-PCR, respectively, which were at least 105 -fold lower than respective ELISA. While spiking synovial fluids of non-TB control subjects with the purified Ag85 protein, LODs of 100 and 120 fg ml-1 were obtained by I-PCR and RT-I-PCR, respectively, thus demonstrating the sample matrix effect. Sensitivities of 87·5 and 70·5% were observed in bodily fluids of confirmed (n = 8) and clinically suspected (n = 51) OATB cases, respectively, by I-PCR, with a specificity of 93·9% (n = 33). Markedly, the sensitivities obtained by I-PCR/RT-I-PCR were significantly higher (P < 0·05-0·01) than ELISA and GeneXpert assay (n = 30). However, no substantial difference in sensitivity was observed between the I-PCR and RT-I-PCR assays. After further improving the accuracy of I-PCR, this test may lead to development of an attractive diagnostic kit.

Paraneoplastic pemphigus as a first sign of metastatic retroperitoneal inflammatory myofibroblastic tumor: (18)F-FDG PET/CT findings.

A 30-year-old female presented with a 3-month history of erosive stomatitis and bullous lesions, along with recurrent episodes of abdominal pain. She was found to have a retroperitoneal lump in left lumbar region. Skin biopsy revealed bullous disorder. CT guided biopsy of the retroperitoneal mass was suggestive of inflammatory myofibroblastic tumor (IMT). She was started on oral steroids and supportive care, and surgery was being planned when she developed respiratory failure. CT chest revealed vertebral metastases. PET/CT for whole body work up revealed a left para-aortic mass along with multiple skeletal metastases. The patient was kept on conservative management. After 3 months, the patient has shown clinical improvement, and an exploratory laparotomy is now being planned for the excision of the tumor, followed by chemotherapy. This case of retroperitoneal IMT is rare in terms of skeletal metastases with paraneoplastic pemphigus.

(99m)Tc-MDP SPECT/CT as the one-stop imaging modality for the diagnosis of early setting of Kienbock's disease.

(99m)Tc-Methylene diphosphonate (MDP) triple phase bone scintigraphy (BS) has a role in early diagnosis of Kienbock's disease, especially when the X-ray is negative. Early diagnosis can result in prompt management of the patient since wrist pain in older individuals due to aging may go unnoticed or be due to other diagnoses with the production of greater damage and eventually a worse prognosis. Herein, we present a case report of a 29-year-old female with Kienbock's disease in whom the X-ray was negative and MRI incorrect. The (99m)Tc-MDP SPECT/CT BS helped the diagnosis of the disease in an early stage (stage 1) and had a clinical impact on the patient's management.

Bilateral primary renal lymphoma in a pediatric patient: staging and response evaluation with ¹8F-FDG PET/CT.

Primary renal lymphoma (PRL) is a rare disease. We here present the case of an 8-year-old child who presented with bilateral renal masses. On biopsy, it was confirmed to be B-cell non-Hodgkin's lymphoma. (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography-computed tomography (PET/CT) for staging demonstrated (18)F-FDG avid bilateral renal masses, with no other abnormal focus. Follow up (18)F-FDG PET/CT showed complete resolution of the disease after six cycles of chemotherapy. Here we have highlighted the potential role of (18)F-FDG PET/CT in staging and response evaluation of a patient with PRL and presented a brief review.