Histological analysis of surgical lumbar intervertebral disc tissue provides evidence for an association between disc degeneration and increased body mass index

<p>Abstract</p> <p>Background</p> <p>Although histopathological grading systems for disc degeneration are frequently used in research, they are not yet integrated into daily care routine pathology of surgical samples. Therefore, data on histopathological changes in surgically excised disc material and their correlation to clinical parameters such as age, gender or body mass index (BMI) is limited to date. The current study was designed to correlate major physico-clinical parameters from a population of orthopaedic spine center patients (gender, age and BMI) with a quantitative histologic degeneration score (HDS).</p> <p>Methods</p> <p>Excised lumbar disc material from 854 patients (529 men/325 women/mean age 56 (15-96) yrs.) was graded based on a previously validated histologic degeneration score (HDS) in a cohort of surgical disc samples that had been obtained for the treatment of either disc herniation or discogenic back pain. Cases with obvious inflammation, tumor formation or congenital disc pathology were excluded. The degree of histological changes was correlated with sex, age and BMI.</p> <p>Results</p> <p>The HDS (0-15 points) showed significantly higher values in the nucleus pulposus (NP) than in the annulus fibrosus (AF) (Mean: NP 11.45/AF 7.87), with a significantly higher frequency of histomorphological alterations in men in comparison to women. Furthermore, the HDS revealed a positive significant correlation between the BMI and the extent of histological changes. No statistical age relation of the degenerative lesions was seen.</p> <p>Conclusions</p> <p>This study demonstrated that histological disc alterations in surgical specimens can be graded in a reliable manner based on a quantitative histologic degeneration score (HDS). Increased BMI was identified as a positive risk factor for the development of symptomatic, clinically significant disc degeneration.</p

Practice patterns analysis of ocular proton therapy centers the international OPTIC survey

PURPOSE To assess the planning, treatment, and follow up strategies worldwide in dedicated proton therapy ocular programs. METHODS AND MATERIALS Ten centers from 7 countries completed a questionnaire survey with 109 queries on the eye treatment planning system TPS , hardware software equipment, image acquisition registration, patient positioning, eye surveillance, beam delivery, quality assurance QA , clinical management, and workflow. RESULTS Worldwide, 28,891 eye patients were treated with protons at the 10 centers as of the end of 2014. Most centers treated a vast number of ocular patients 1729 to 6369 . Three centers treated fewer than 200 ocular patients. Most commonly, the centers treated uveal melanoma UM and other primary ocular malignancies, benign ocular tumors, conjunctival lesions, choroidal metastases, and retinoblastomas. The UM dose fractionation was generally within a standard range, whereas dosing for other ocular conditions was not standardized. The majority 80 of centers used in common a specific ocular TPS. Variability existed in imaging registration, with magnetic resonance imaging MRI rarely being used in routine planning 20 . Increased patient to full time equivalent ratios were observed by higher accruing centers P .0161 . Generally, ophthalmologists followed up the post radiation therapy patients, though in 40 of centers radiation oncologists also followed up the patients. Seven centers had a prospective outcomes database. All centers used a cyclotron to accelerate protons with dedicated horizontal beam lines only. QA checks range, modulation varied substantially across centers. CONCLUSIONS The first worldwide multi institutional ophthalmic proton therapy survey of the clinical and technical approach shows areas of substantial overlap and areas of progress needed to achieve sustainable and systematic management. Future international efforts include research and development for imaging and planning software upgrades, increased use of MRI, development of clinical protocols, systematic patient centered data acquisition, and publishing guidelines on QA, staffing, treatment, and follow up parameters by dedicated ocular programs to ensure the highest level of care for ocular patient

Dose-response and normal tissue complication probabilities after proton therapy for choroidal melanomas

Purpose Normal tissue complication probability (NTCP) models could aid the understanding of dose-dependence of radiation-induced toxicities after eye-preserving radiotherapy of choroidal melanomas. We performed NTCP-modelling and established dose-response relationships for visual acuity deterioration and common late complications after treatments with proton therapy (PT). Design Retrospective study from single large referral centre. Subjects We considered patients diagnosed with choroidal melanoma and primarily treated with hypo-fractionated PT (52 Gy physical dose in 4 fractions). 1020 patients had complete visual acuity deterioration information, 991 patients had complete information on late complications. Methods Treatment details and dose-volume histograms (DVHs) for relevant anatomical structures and patient and tumour characteristics were available from a dedicated ocular database. Lasso variable selection was used to identify variables with the strongest impact on each endpoint, followed by multivariable Cox regressions and logistic regressions to analyse the relationship between dose, clinical characteristics and clinical outcomes. Dose-response relationships were estimated, adjusting for relevant clinical variables. Main Outcome Measures Dose-response relationship for visual acuity deterioration and late complications Results Dose metrics for several structures (i.e. optic disc, macula, retina, globe, lens, ciliary body) correlated with clinical outcome. The near-maximum dose to the macula (macula D2%) showed the strongest correlation with visual acuity deterioration. Retina D20% was the only variable with clear impact on the risk of developing maculopathy; optic disc D20% had the largest impact on optic neuropathy; cornea D20% had the largest impact on neovascular glaucoma; ciliary body D20% had the largest impact on ocular hypertension; the volume of the ciliary body receiving 26 Gy (ciliary body V26Gy) was the only variable associated with the risk of cataract; and retina V52Gy was associated with the risk of retinal detachment. Optic disc-tumour distance was the only variable associated with dry eye syndrome in the absence of DVH for the lachrymal gland. Conclusions Visual acuity deterioration and specific late complications demonstrated dependence on dose delivered to normal structures in the eye after PT for choroidal melanoma. Visual acuity deterioration depended on dose to a range of structures, while more specific complications were primarily related to dose metrics for specific structures