Optimization of psoriasis assessment system based on patch images.

Psoriasis is a chronic inflammatory skin disease that occurs in various forms throughout the body and is associated with certain conditions such as heart disease, diabetes, and depression. The psoriasis area severity index (PASI) score, a tool used to evaluate the severity of psoriasis, is currently used in clinical trials and clinical research. The determination of severity is based on the subjective judgment of the clinician. Thus, the disease evaluation deviations are induced. Therefore, we propose optimal algorithms that can effectively segment the lesion area and classify the severity. In addition, a new dataset on psoriasis was built, including patch images of erythema and scaling. We performed psoriasis lesion segmentation and classified the disease severity. In addition, we evaluated the best-performing segmentation method and classifier and analyzed features that are highly related to the severity of psoriasis. In conclusion, we presented the optimal techniques for evaluating the severity of psoriasis. Our newly constructed dataset improved the generalization performance of psoriasis diagnosis and evaluation. It proposed an optimal system for specific evaluation indicators of the disease and a quantitative PASI scoring method. The proposed system can help to evaluate the severity of localized psoriasis more accurately.

Plan Quality and Secondary Cancer Risk Assessment in Patients with Benign Intracranial Lesions after Radiosurgery using the CyberKnife M6 Robotic Radiosurgery System.

This study was performed to examine the quality of planning and treatment modality using a CyberKnife (CK) robotic radiosurgery system with multileaf collimator (MLC)-based plans and IRIS (variable aperture collimator system)-based plans in relation to the dose-response of secondary cancer risk (SCR) in patients with benign intracranial tumors. The study population consisted of 15 patients with benign intracranial lesions after curative treatment using a CyberKnife M6 robotic radiosurgery system. Each patient had a single tumor with a median volume of 6.43 cm3 (range, 0.33-29.72 cm3). The IRIS-based plan quality and MLC-based plan quality were evaluated by comparing the dosimetric indices, taking into account the planning target volume (PTV) coverage, the conformity index (CI), and the dose gradient (R10% and R50%). The dose-response SCR with sarcoma/carcinoma induction was calculated using the concept of the organ equivalent dose (OED). Analyses of sarcoma/carcinoma induction were performed using excess absolute risk (EAR) and various OED models of dose-response type/lifetime attributable risk (LAR). Moreover, analyses were performed using the BEIR VII model. PTV coverage using both IRIS-based plans and MLC-based plans was identical, although the CI values obtained using the MLC-based plans showed greater statistical significance. In comparison with the IRIS-based plans, the MLC-based plans showed better dose falloff for R10% and R50% evaluation. The estimated difference between Schneider's model and BEIR VII in linear-no-threshold (Lnt) cumulative EAR was about twofold. The average values of LAR/EAR for carcinoma, for the IRIS-based plans, were 25% higher than those for the MLC-based plans using four SCR models; for sarcoma, they were 15% better in Schneider's SCR models. MLC-based plans showed slightly better conformity, dose gradients, and SCR reduction. There was a slight increase in SCR with IRIS-based plans in comparison with MLC-based plans. EAR analyses did not show any significant difference between PTV and brainstem analyses, regardless of the tumor volume. Nevertheless, an increase in target volume led to an increase in the probability of SCR. EAR showed statistically significant differences in the soft tissue according to tumor volume (1-10 cc and ≥10 cc).

A Monte Carlo study of bone-tissue interface microdosimeters.

Radiation-induced bone diseases were frequently reported in radiotherapy patients. To study the diseases, microdosimeters were constructed with walls of A150-A150, A150-B100, B100-A150 and B100-B100 interfaces. Monte Carlo simulations of these microdosimeters were performed to determine the lineal energy spectra of an interface site at different depths in water for 230 MeV protons. Comparing these spectra with data of ICRU tissue and bone walls, better agreements were found at shallow depths for protons and delta-rays than deep depths for nuclear interactions.

Improvements in the quantitative assessment of cerebral blood volume and flow with the removal of vessel voxels from MR perfusion images.

OBJECTIVE: To improve the quantitative assessment of cerebral blood volume (CBV) and flow (CBF) in the brain voxels from MR perfusion images. MATERIALS AND METHODS: Normal brain parenchyma was automatically segmented with the time-to-peak criteria after cerebrospinal fluid removal and preliminary vessel voxel removal. Two scaling factors were calculated by comparing the relative CBV and CBF of the segmented normal brain parenchyma with the absolute values in the literature. Using the scaling factors, the relative values were converted to the absolute CBV and CBF. Voxels with either CBV > 8 mL/100 g or CBF > 100 mL/100 g/min were characterized as vessel voxels and were excluded from the quantitative measurements. RESULTS: The segmented brain parenchyma with normal perfusion was consistent with the angiographic findings for each patient. We confirmed the necessity of dual thresholds including CBF and CBV for proper removal of vessel voxels. The scaling factors were 0.208 ± 0.041 for CBV, and 0.168 ± 0.037, 0.172 ± 0.037 for CBF calculated using standard and circulant singular value decomposition techniques, respectively. CONCLUSION: The automatic scaling and vessel removal techniques provide an alternative method for obtaining improved quantitative assessment of CBV and CBF in patients with thromboembolic cerebral arterial disease.

Design and verification of shielding for the advanced spent fuel conditioning process facility.

An Advanced spent fuel Conditioning Process Facility (ACPF) has recently been constructed by a modification of previously unused cells. ACPF is a hot cell with two rooms located in the basement of the Irradiated Materials Experiment Facility (IMEF) at the Korea Atomic Energy Research Institute. This is for demonstrating the advanced spent fuel conditioning process being proposed in Korea, which is an electrolytic reduction process of spent oxide fuels into a metallic form. The ACPF was designed with a more than 90 cm thick high density concrete shield wall to handle 1.38 PBq (37,430 Ci) of radioactive materials with dose rates lower than 10 muSv h in the operational areas (7,000 zone) and 150 muSv h in the service areas (8,000 zone). In Monte Carlo calculations with a design basis source inventory, the results for the bounding wall showed a maximum of 3 muSv h dose rate at an exterior surface of the ACPF for gamma radiation and 0.76 muSv h for neutrons. All the bounding structures of the ACPF were investigated to check on the shielding performance of the facility to ensure the radiation safety of the facility. A test was performed with a 2.96 TBq (80 Ci) 60Co source unit and the test results were compared with the calculation results. A few failure points were discovered and carefully fixed to meet the design criteria. After fixing the problems, the failure points were rechecked and the safety of the shielding structures was confirmed. In conclusion, it was confirmed that all the investigated parts of the ACPF passed the shielding safety limits by using this program and the ACPF is ready to fulfill its tasks for the advanced spent fuel conditioning process.

Cost-effectiveness analysis of an intranasal influenza vaccine for the prevention of influenza in healthy children.

OBJECTIVE: Intranasal influenza vaccine has proven clinical efficacy and may be better tolerated by young children and their families than an injectable vaccine. This study determined the potential cost-effectiveness (CE) of an intranasal influenza vaccine among healthy children. METHODS: We conducted a CE analysis of data collected between 1996 and 1998 during a prospective 2-year efficacy trial of intranasal influenza vaccine, supplemented with data from the literature. The CE analysis included both direct and indirect costs. We enrolled 1602 healthy children aged 15 to 71 months in year 1, 1358 of whom were enrolled in year 2. One or 2 doses of intranasal influenza vaccine or placebo were administered to measure the cost per febrile influenza-like illness (ILI) day avoided. RESULTS: During the 2-year study period, vaccinated children had an average of 1.2 fewer ILI fever days/child than unvaccinated children. In an individual-based vaccine delivery scenario with vaccine given twice in the first year and once each year thereafter at an assumed base case total cost of $20 for the vaccine and its administration (ie, per dose), CE was approximately $30/febrile ILI day avoided. CE ranged from $10 to $69/febrile ILI day avoided at $10 to $40/dose, respectively. In a group-based delivery scenario, vaccination was cost saving compared with placebo and remained so if vaccine cost was <$28 (the break-even price per dose). In the individual-based scenario, vaccination was cost saving if vaccine cost was <$5. In this scenario, nearly half of lost productivity in the vaccine group was attributable to vaccine visits, which overshadowed the relatively modest savings in ILI-associated costs averted. CONCLUSIONS: Routine use of intranasal influenza vaccine among healthy children may be cost-effective and may be maximized by using group-based vaccination approaches. cost-effectiveness, influenza, vaccine, children.

Disparity in our nation's health: improving access to oral health care for children.

The American public and its policymakers are beginning to recognize oral health as an integral part of overall health. Utilization of new technologies and preventive treatments has set a higher standard in the public's expectations of oral health and dentistry. There have been marked improvements in oral health indicators in the United States during the past century. However, some populations have not enjoyed the benefits realized by most Americans.