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Purpose: Due to high specificity and sensitivity noncontrast computerized tomography is increasingly used to diagnose and follow patients with ureteral stones. We evaluated the feasibility of limited field noncontrast computerized tomography to follow patients with ureteral stones., Materials and Methods: Included in the study were 71 patients who underwent diagnostic and followup noncontrast computerized tomography due to ureteral stones. According to stone position on the first diagnostic scan a limited field batch from the followup scan was formed and examined by an independent radiologist. Radiation doses and rates of potentially missed findings in the batch were compared to those of the full followup noncontrast scan., Results: Average full followup noncontrast computerized tomography length was 46.5 cm and average batch length was 20.7 and 13.8 cm for proximal and distal stones, respectively. The average full followup noncontrast scan radiation dose was 12.2 mSv. Average batch doses were 6.1 and 4.1 mSv for proximal and distal stones, respectively (p = 0.002), resulting in a radiation exposure reduction of 48.8% for proximal stones and 66% for distal stones. In 3 cases additional clinical information (not including hydronephrosis) was missed when relying only on batch images. This additional information did not impact further urological treatment., Conclusions: Limited field noncontrast computerized tomography is a feasible option for following patients diagnosed with ureteral stones. It may lead to significantly lower radiation exposure., (Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Simian virus 40 (SV40) is capable of inducing cellular DNA synthesis in permissive and nonpermissive cells. Utilizing flow cytometry, we analyzed the DNA content changes in two diploid human cell strains and two monkey cell lines. The osteogenesis imperfecta (OI) human skin fibroblasts were induced into DNA synthesis, and within one to two cell generations, a polyploid cell population was produced. With WI-38 phase II cells, a similar pattern of increased cycling of cells into DNA synthesis was observed; however, the majority (approximately 60%) of the cells were blocked in the G2 + M phase of the cell cycle. At later time intervals, an increase in the G1 population was demonstrated. The two monkey cell lines responded to SV40 virus with an accumulation of cells in the G2 + M phase of the cell cycle. Thus, two diploid human cell strains exhibited different cell cycle kinetics early after infection with SV40 virus. The one strain (WI-38) behaved similarly to the two monkey cell lines studied. The other strain (OI) responded similarly to nonpermissive (transforming) cells infected with SV40 virus.