ABSTRACT
PURPOSE: This study aimed to evaluate the factors associated with retinal pigment epithelium (RPE) tear development in the early phase after anti-vascular endothelial growth factor (VEGF) drug initiation in eyes with neovascular age-related macular degeneration (nAMD) and retinal pigment epithelial detachment (PED). METHODS: Treatment-naive eyes with nAMD and PED for which anti-VEGF drug injections had been initiated and followed up for at least 3 months after the 1st anti-VEGF drug injection, were retrospectively investigated. Baseline characteristics of the PEDs, including type, height, and area, were evaluated using fundus photographs, fluorescein angiography, and optical coherence tomography images. The association between patient age, sex, medical history, PED characteristics, and the development of RPE tears within 3 months of starting anti-VEGF therapy was examined. RESULTS: This study included 244 eyes (230 patients; mean age 75.0 years, 159 males and 71 females). RPE tears occurred in 13 eyes (5.3%) within 3 months of the start of anti-VEGF therapy. Multivariate analysis showed an association of the development of RPE tears with PED height (every 100 µm, odds ratio [OR]: 1.50, 95% confidence interval [CI]: 1.07-2.12, p = 0.019), PED area (every 10 mm2, OR: 3.02, CI: 1.22-7.46, p = 0.016), and the presence of fibrovascular PED (OR: 59.22, CI: 4.12-850.59, p = 0.002). Eyes with cleft (the hypo-reflective space beneath the fibrovascular PED) were more likely to develop an RPE tear (p = 0.01, χ-square test). CONCLUSIONS: Fibrovascular PED, large PED area, high PED height, and the cleft finding are independent risk factors for the development of RPE tears early after the administration of anti-VEGF drugs.
ABSTRACT
A radiophotoluminescent glass dosimeter (RGD) is used for a postal audit of a photon beam because of its various excellent characteristics. However, it has not been used for scanning proton beams because its response characteristics have not been verified. In this study, the response of RGD to scanning protons was investigated to develop a dosimetry protocol using the linear energy transfer (LET)-based correction factor. The responses of RGD to four maximum-range-energy-pattern proton beams were verified by comparing it with ionization chamber (IC) dosimetry. The LET at each measurement depth was calculated via Monte Carlo (MC) simulation. The LET correction factor ( k LET RGD ) was the ratio between the uncorrected RGD dose ( D raw RGD ) and the IC dose at each measurement depth. k LET RGD can be represented as a function of LET using the following equation: k LET RGD LET = - 0.035 LET + 1.090 . D raw RGD showed a linear under-response with increasing LET, and the maximum dose difference between the IC dose and D raw RGD was 15.2% at an LET of 6.07 keV/µm. The LET-based correction dose ( D LET RGD ) conformed within 3.6% of the IC dose. The mean dose difference (±SD) of D raw RGD and D LET RGD was -2.5 ± 6.9% and 0.0 ± 1.6%, respectively. To achieve accurate dose verification for scanning proton beams using RGD, we derived a linear regression equation based on LET. The results show that with appropriate LET correction, RGD can be used for dose verification of scanning proton beams.
Subject(s)
Linear Energy Transfer , Proton Therapy , Humans , Monte Carlo Method , Protons , Radiation Dosimeters , RadiometryABSTRACT
The aim of this study was to investigate the condition of the maxillary lateral incisors and evaluate the methods used for cleft closure in patients with cleft lip and palate, including the treatment of the maxillary lateral incisors. A total of 214 patients (260 clefts) with alveolar clefts who had started Phase II treatment and entered the maintenance period at the Department of Orthodontics at Tokyo Dental College, Chiba Hospital, between 1975 and 2014 were included. Panoramic, intraoral, and occlusal radiographs, as well as intraoral photographs and medical records, were used to investigate cleft classification, the presence or absence and location of maxillary lateral incisors, and frequency and treatment method for peg lateral incisors in the cleft region. There were more unilateral cleft cases (78.5%) than bilateral cleft cases. The prevalence of congenital absence of the maxillary lateral incisors was similar between unilateral (53.0%) and bilateral cases (53.3%). Peg laterals occurred frequently, with 89.9% occurring in unilateral cases. The maxillary lateral incisors were more commonly found in the secondary than in the primary palate. The number of non-extraction cases was larger than that of extraction cases, regardless of cleft type or the location of the peg laterals. In many cases, the peg laterals were treated with non-extraction and space closure or crown modification. These results suggest that, depending on their condition, the peg laterals should be preserved as much as possible in devising a treatment plan.
Subject(s)
Cleft Lip , Humans , Incisor , Maxilla , Retrospective Studies , Surveys and Questionnaires , TokyoABSTRACT
Intensity-modulated radiation therapy (IMRT) has become a popular choice for breast cancer treatment. We aimed to evaluate and compare the robustness of each optimization method used for breast IMRT using TomoTherapy. A retrospective analysis was performed on 10 patients with left breast cancer. For each optimization method (clipping, virtual bolus, and skin flash), a corresponding 50 Gy/25 fr plan was created in the helical and direct TomoTherapy modes. The dose-volume histogram parameters were compared after shifting the patients anteriorly and posteriorly. In the helical mode, when the patient was not shifted, the median D1cc (minimum dose delivered to 1 cc of the organ volume) of the breast skin for the clipping and virtual bolus plans was 52.2 (interquartile range: 51.9-52.6) and 50.4 (50.1-50.8) Gy, respectively. After an anterior shift, D1cc of the breast skin for the clipping and virtual bolus plans was 56.0 (55.6-56.8) and 50.9 (50.5-51.3) Gy, respectively. When the direct mode was used without shifting the patient, D1cc of the breast skin for the clipping, virtual bolus, and skin flash plans was 52.6 (51.9-53.1), 53.4 (52.6-53.9), and 52.3 (51.7-53.0) Gy, respectively. After shifting anteriorly, D1cc of the breast skin for the clipping, virtual bolus, and skin flash plans was 55.6 (54.1-56.4), 52.4 (52.0-53.0), and 53.6 (52.6-54.6) Gy, respectively. The clipping method is not sufficient for breast IMRT. The virtual bolus and skin flash methods were more robust optimization methods according to our analyses.
Subject(s)
Breast Neoplasms , Radiotherapy Planning, Computer-Assisted , Radiotherapy, Intensity-Modulated , Humans , Female , Breast Neoplasms/radiotherapy , Breast Neoplasms/diagnostic imaging , Radiotherapy Dosage , Middle Aged , Dose-Response Relationship, Radiation , Retrospective Studies , Breast/diagnostic imagingABSTRACT
BACKGROUND: Although anti-vascular endothelial growth factor (anti-VEGF) therapy is the first choice of treatment for eyes with neovascular age-related macular degeneration (AMD), it sometimes results in retinal pigment epithelium (RPE) tears. This study presents the detailed clinical characteristics of RPE tears to help predict their occurrence before anti-VEGF therapy initiation. METHODS: This study retrospectively analyzed neovascular age-related macular degeneration (nAMD) patients who visited the Kyushu University Hospital and started anti-VEGF therapy between April 2013 and June 2020. Using medical records, we collected the clinical data of patients with RPE tears, including age, sex, best-corrected visual acuity (BCVA), number of anti-VEGF drug injections and the type and size of pigment epithelial detachment (PED). RESULTS: RPE tears occurred in 16 (1.50%) eyes of 16 patients in all 1068 nAMD eyes of 987 patients. The mean age of these patients with RPE tear was 81.7 ± 8.7 years. Fifteen eyes had typical AMD and one eye had polypoidal choroidal vasculopathy. The mean number of anti-VEGF drug injections before RPE tears was 5.0 ± 5.1. All patients experienced PED before the RPE tear (hemorrhagic, 4 eyes; serous vascular, 2 eyes; fibrovascular, 10 eyes). The average PED height and area were 615.7 ± 175.3 µm and 21.0 ± 7.2 mm2, respectively. The sub-RPE cleft was observed in 10 eyes. The logMAR BCVA immediately after the RPE tear (0.73 ± 0.40) at 6 months (0.86 ± 0.51) and 12 months (0.84 ± 0.43) after the RPE tear were significantly worse than that before the RPE tear (0.58 ± 0.31; p < 0.05). The BCVA of patients with RPE tears that spread to the fovea was poorer than that of patients without RPE tears. CONCLUSIONS: In patients with nAMD, RPE tears tended to occur in typical AMD eyes with high or large PEDs, and sub-RPE clefts. The visual prognosis depended on whether the RPE tear included the fovea.
ABSTRACT
A radiophotoluminescent glass dosimeter (RGD) is widely used in postal audit system for photon beams in Japan. However, proton dosimetry in RGDs is scarcely used owing to a lack of clarity in their response to beam quality. In this study, we investigated RGD response to beam quality for establishing a suitable linear energy transfer (LET)-corrected dosimetry protocol in a therapeutic proton beam. The RGD response was compared with ionization chamber measurement for a 100-225 MeV passive proton beam. LET of the measurement points was calculated by the Monte Carlo method. An LET-correction factor, defined as a ratio between the non-corrected RGD dose and ionization chamber dose, of 1.226×(LET)-0.171 was derived for the RGD response. The magnitude of the LET-dependence of RGD increased with LET; for an LET of 8.2 keV/µm, the RGD under-response was up to 16%. The coefficient of determination, mean difference ± SD of non-corrected RGD dose, residual range-corrected RGD dose, and LET-corrected RGD dose to the ionization chamber are 0.923, 3.7 ± 4.2%, -2.4 ± 7.5%, and 0.04 ± 2.1%, respectively. The LET-corrected RGD dose was within 5% of the corresponding ionization chamber dose at all energies until 200 MeV, where it was 5.3% lower than the ionization chamber dose. A corrected LET-dependence of RGD using a correction factor based on a power function of LET and precise dosimetric verification close to the maximum LET were realized here. We further confirmed establishment of an accurate postal audit under various irradiation conditions.
Subject(s)
Linear Energy Transfer , Proton Therapy , Japan , Monte Carlo Method , Protons , Radiation Dosimeters , RadiometryABSTRACT
BACKGROUND: While the world's population is growing older, healthy life expectancy is not increasing. The Japanese Orthopedic Association proposed the concept of 'locomotive syndrome,' manifested as a decline in mobility functions, and introduced a short test battery for assessing the risk of this syndrome. The test battery includes the 'stand-up test,' 'two-step test,' and '25-question Geriatric Locomotive Function Scale' (25-question GLFS). The purpose of locomotion training is to improve and sustain standing and gait functions. However, the place where locomotion training can be provided and followed up has not been decided upon. Therefore, a study was conducted to explore the effect of locomotive syndrome improvement by continuous locomotion training provided at community pharmacies. The objective of this study was to evaluate the effect of pharmacists' instructions and follow-up on the compliance and effectiveness of locomotion training. METHODS: The inclusion criteria were 1) age ≥ 65 years and 2) decline in mobility functions. Guidance on how to perform locomotion training was provided by a pharmacist at the pharmacy. The participants performed locomotion training at home. They were tested and instructed at the pharmacy once a month for 3 months. The main outcome measures were test battery results and the percentage of number of days participants who were able to do the training at home. RESULTS: Eleven participants were analysed. The minimum implementation percentage was 78%. Improvements were observed in 25-question GLFS, muscle strength, and standing time on one leg. Three participants no longer showed a noticeable decline in mobility function. CONCLUSION: Continuous locomotion training provided at pharmacies could contribute to locomotive syndrome prevention. TRIAL REGISTRATION: This study was registered with the University hospital Medical Information Network Clinical Trials Registry (UMIN-CTR; identification No. UMIN000027963 . Registered 28 June 2017).