The Strain Response to Intraocular Pressure Decrease in the Lamina Cribrosa of Patients with Glaucoma.

OBJECTIVE: To measure biomechanical strains in the lamina cribrosa (LC) of living human eyes with intraocular pressure (IOP) lowering. DESIGN: Cohort study. PARTICIPANTS: Patients with glaucoma underwent imaging before and after laser suturelysis after trabeculectomy surgery (29 image pairs; 26 persons). INTERVENTION: Noninvasive imaging of the eye. MAIN OUTCOME MEASURES: Strains in optic nerve head tissue and changes in depths of the anterior border of the LC. RESULTS: Intraocular pressure decreases caused the LC to expand in thickness in the anterior-posterior strain (Ezz = 0.94 ± 1.2%; P = 0.00020) and contract in radius in the radial strain (Err = - 0.19 ± 0.33%; P = 0.0043). The mean LC depth did not significantly change with IOP lowering (1.33 ± 6.26 µm; P = 0.26). A larger IOP decrease produced a larger, more tensile Ezz (P < 0.0001), greater maximum principal strain (Emax; P < 0.0001), and greater maximum shear strain (Γmax; P < 0.0001). The average LC depth change was associated with the Γmax and radial-circumferential shear strain (Erθ; P < 0.02) but was not significantly related to tensile or compressive strains. An analysis by clock hour showed that in temporal clock hours 3 to 6, a more anterior LC movement was associated with a more positive Emax, and in clock hours 3, 5, and 6, it was associated with a more positive Γmax. At 10 o'clock, a more posterior LC movement was related to a more positive Emax (P < 0.004). Greater compliance (strain/ΔIOP) of Emax (P = 0.044), Γmax (P = 0.052), and Erθ (P = 0.018) was associated with a thinner retinal nerve fiber layer. Greater compliance of Emax (P = 0.041), Γmax (P = 0.021), Erθ (P = 0.024), and in-plane shear strain (Erz; P = 0.0069) was associated with more negative mean deviations. Greater compliance of Γmax (P = 0.055), Erθ (P = 0.040), and Erz (P = 0.015) was associated with lower visual field indices. CONCLUSIONS: With IOP lowering, the LC moves either into or out of the eye but, on average, expands in thickness and contracts in radius. Shear strains are nearly as substantial as in-plane strains. Biomechanical strains are more compliant in eyes with greater glaucoma damage. This work was registered at ClinicalTrials.gov as NCT03267849.

Comparison of Patient-Reported Functional Recovery From Different Types of Ophthalmic Surgery.

PURPOSE: To characterize and compare patient-reported recovery of function after cataract or glaucoma surgery using a novel visual analog scale. DESIGN: Prospective observational cohort study. METHODS: Daily for 2 weeks and weekly thereafter, patients recovering from trabeculectomy, tube shunt implantation, or cataract extraction (CE) completed a diary-style questionnaire including visual analog scales (VASs; scored 0-100) grading pain and global function. Clinical examination data and medical histories were collected. Generalized estimating equation models evaluated associations between VAS function scores and pain or visual acuity (VA) and compared scores between surgery types. RESULTS: Among 51 participants followed for 12 weeks, tube shunt placement reduced postoperative day 1 (POD1) function by 47 of 100 points vs CE (P = .006), while trabeculectomy did not reduce POD1 function vs CE (P = .33). After CE, trabeculectomy, and tube shunt placement, average VAS function scores increased 13.94 per week for 2 weeks (P < .001), 4.18 per week for 4 weeks (P = .02), and 7.76 per week for 7 weeks (P < .001), respectively. After those timepoints, there was no further significant change. Beyond 2 weeks, pain levels plateaued, and VA returned to baseline across surgery types; function was inversely related to pain or VA only for the first 2 or 4 weeks, respectively. CONCLUSIONS: Patients recovering from cataract and glaucoma surgery report reduced function in the postoperative period. Tube shunt implantation causes greater morbidity than trabeculectomy, and both are associated with slower improvement than CE. Early postoperative function is associated with VA and pain, but neither fully explains reported impairment. A VAS for function may efficiently capture postoperative recovery.

Five-Year Survival is Not a Useful Measure for Cancer Control in the Population: an Analysis Based on UK Data

Background: Five-year survival is an important metric for progress in cancer control broadly used both in the cancer literature and by the public. In order to assess its validity and relation to other common metrics, we analyzed the relationship between 5-year survival, incidence and mortality using publicly available cancer registry data from England and Wales. Methods: Five-year survival, incidence and mortality data were obtained from the online database of a registered charity, Cancer Research UK. We extracted sex-specific age-standardized mortality, incidence, and 5-year survivalfor16 types of cancer over the period from 1976 to 1995. The relationships between 5-year survival, incidence and mortality were estimated using both Pearson and Spearman correlation coefficients. Results: All 16cancer types showed an increase in 5-year survival for both genders from 1976 to 1995, ranging from 0.2% (pancreas and lung cancer) to 16.6% (prostate cancer) for males and 0.2% (pancreas cancer) to 16.6% (leukemia) for females. From 1976 to 1995, there was no significant correlation between changes in 5-year survival and cancer mortality for either sex (males, Pearson r=0.16, Spearman r=-0.06; females, Pearson r=-0.33, Spearman r=-0.43). A positive relationship between 5-year survival and incidence was noted among males, but not among females (males, Pearson r=0.61, Spearman r=0.53; females, Pearson r=0.03, Spearman r=0.11). However, after excluding breast and prostate cancer, the positive association became weaker and became statistically non-significant for males (Pearson r=0.47; Spearman r=0.41). Conclusions: Our findings suggest that there are no reliable relationships between changes in 5-year survival and cancer incidence or mortality. Increases in 5-year survival might therefore represent poor indicators of progress in cancer control at the population level. In the absence of over-diagnosis, 5-year survival might only indicate improved diagnosis and treatment in clinical practice.

Does Shared Decision Making in Cancer Treatment Improve Quality of Life? A Systematic Literature Review.

BACKGROUND: The growing consensus espousing the use of shared decision making (SDM) in cancer treatment has coincided with the rise of health care evaluation paradigms that emphasize quality of life (QOL) as a central outcome measure. This review systematically examines the association between treatment SDM and QOL outcomes in cancer. METHODS: A range of bibliographic databases and gray literature sources was searched. The search retrieved 16,726 records, which were screened by title, abstract, and full text to identify relevant studies. The review included 17 studies with a range of study designs and populations. Data were extracted on study methods, participants, setting, study or intervention description, outcomes, main findings, secondary findings, and limitations. Quality appraisal was used, in conjunction with a narrative approach, to synthesize the evidence. RESULTS: The review found weak, but suggestive, evidence for a positive association between perceived patient involvement in decision making, a central dimension of SDM, and QOL outcomes in cancer. The review did not find evidence for an inverse association between SDM and QOL. The poor methodological quality and heterogeneity of the extant literature constrained the derived conclusions. In addition, the literature commonly treated various subscales of QOL instruments as separate outcomes, increasing the probability of spurious findings. CONCLUSIONS: There is weak evidence that aspects of shared decision-making approaches are positively associated with QOL outcomes and very little evidence of a negative association. The extant literature largely assessed patient involvement, only capturing one aspect of the shared decision-making construct, and is of poor quality, necessitating robust studies examining the association.