Unexpected FDG-PET uptake in the gastrointestinal tract: endoscopic and histopathological correlations.

AIM: To investigate the nature and significance of unexpected positron emission tomography with fluorodeoxyglucose (FDG-PET) uptake within the gastrointestinal tract (GIT). METHODS: Patients with unexpected FDG-PET findings in the GIT were evaluated. All patients had a previous confirmed malignancy, either solid or lymphoproliferative. The radiologic reports were performed by experienced radiologists with an exclusive PET expertise. Endoscopy, i.e., esophagogastroduodenoscopy (EGD) and colonoscopy, and histopathological evaluation of all findings was performed in all patients in accordance to the FDG-PET results. The findings from each of these modalities were compared to each other. Both clinically significant and insignificant findings were assessed. RESULTS: Seventy-two patients were endoscopically evaluated. Twenty-seven patients (37.5%) had primarily a lymphoproliferative tumor and 45 (62.5%) had solid tumors. In 50 patients (69.4%) the endoscopic examination revealed lesions in the same anatomical areas as the FDG-PET findings. Among these 50 patients, malignant and premalignant lesions i.e., adenomatous polyps were found in 16 (32%) and 9 (18%) patients, respectively. Inflammation was noted in an additional 20 patients (40%). Compared to primary solid tumors, a background of primary lymphoproliferative malignancy was more likely to reveal an additional primary malignancy (15.6% vs 33.3%, respectively, P < 0.01). EGD compared to colonoscopy, revealed altogether 11 (25.6%) new malignancies compared to 5 (17.2%), respectively, P = 0.12. No GIT clinically significant findings were overseen by the FDG-PET. CONCLUSION: Unexpected FDG uptake in the GIT is commonly encountered and may contain significant findings. Endoscopy evaluation is justified in order to detect these additional findings.

Electromagnetic interference from wireless video-capsule endoscopy on implantable cardioverter-defibrillators.

OBJECTIVES: The purpose of this study was to evaluate potential interference between the Pill-cam video-capsule and implanted cardio-defibrillators (ICD) in both in vitro and in vivo test environments. METHODS: Phase I consisted of in vitro testing utilized 6 ICD models. Each was placed in a saline gel bath in conjunction with a tool designed to emit the same wave length as the Pill-Cam (the Test Cap). Tests were performed at both the manufacturer's nominal and most sensitive settings with the test probe placed at 1, 5, 10, and 15 cm from three different points. There were emissions of 10-, 30-, and 60- second duration at each location. Phase II was the in vivo study utilizing patients with implanted ICDs for standard clinical reasons who were undergoing evaluation with the Test Cap. RESULTS: In Phase I, 864 tests were performed involving the 6 ICDs. There was totally normal behavior in 5 of the devices. The Biotronik Belos (Berlin, Germany) demonstrated oversensing and delivery of inappropriate therapy. In phase II, 6 patients underwent a total number of 288 tests (48 in each patient). There were 4 men and 2 women, mean age 61 (33-77) and none demonstrated any adverse interactions. CONCLUSIONS: In patients with devices identical to those evaluated that showed no interference, the use of the Pill-Cam is safe. However, in patients with a Biotronik Belos ICD (or any other nontested ICD) the use of the Pill-Cam should be done only in-hospital, after suspended ICD therapy and in conjunction with close monitoring.

Electromagnetic interference with implantable cardiac pacemakers by video capsule.

BACKGROUND: Electromagnetic fields, such as those generated by cellular phones and metal detectors, may interfere with normal pacemaker function. However, it remains unclear whether the wireless capsule endoscope interacts with implanted pacemakers. This prospective study evaluated potential interactions between the M2A video capsule (Given Imaging, Yoknam, Israel) and implanted pacemakers. METHODS: A total of 100 consecutive patients (70 men, 30 women) with an implanted pacemaker (95 on bipolar mode) were studied. The testing was performed with a functional testing device (Test Cap) for the Given Diagnostic System that reproduces the effect of the video capsule by transmitting at exactly the same frequency. During continuous electrocardiographic monitoring and recording, 100 tests were carried out without changing the pacemaker settings. Those with a positive result were retested 1 week later. RESULTS: The 100 pacemakers evaluated in the study population included the following: 70 dual chamber (11 DDD, 56 DDDR, 3 VDD) and 30 ventricular inhibited (12 VVI, 18 VVIR). In 4 of the 100 patients, pacemaker interference (noise-mode function forcing a synchronous mode) was registered during the Test Cap operation. Three patients had a dual-chamber pacemaker, and one had a single-chamber pacemaker. The interference was reproducible in all cases 1 week later. None of the implanted pacemakers tested was affected by oversensing. CONCLUSIONS: Electromagnetic interferences with pacemakers from the M2A video capsule can occur, but this is without clinical significance. No potentially dangerous pacemaker inhibition was observed.