Essential requisite for the preservation of normal brain activity is to maintain a narrow and stable homeostatic control in the neuronal environment of the CNS. Blood flow alterations and altered vessel permeability are considered key determinants in the pathophysiology of brain injuries. We will review the present-day literature on the anatomy, development and physiological mechanisms of the blood-brain barrier, a distinctive and tightly regulated interface between the CNS and the peripheral circulation, playing a crucial role in the maintenance of the strict environment required for normal brain function.

From this study we determined the most important prognostic factor in zone III open globe injuries is the presenting acuity. Other prognostic factors associated with a poor final outcome are eyelid injury, iris deformity, lens damage, ocular hypotonia, coexisting injuries and low ocular trauma score (< or =2). Posterior open eye injuries were most commonly owing to metal entering the eyes of young men.

Background: An understanding of statistical methods and basic epidemiology are crucial for the practice of modern medicine. Aims: To assess (1) the knowledge of basic methods of conducting research and data analysis among residents and practicing doctors and (2) the effect of country of medical school graduation, professional status, medical article reading and writing experience on the level of this knowledge. Methods: Data were collected by means of a supervised self-administered questionnaire, which was distributed among doctors at Soroka Medical Center, Beer-Sheva, Israel. The questionnaire included 10 multiple-choice questions on basic epidemiology and statistics, and respondent demographical data. Results: Of the 260 eligible doctors, 219 (84.2%) returned completed questionnaires. Of the 219 doctors, 50% graduated more than 8.5 years ago, 39.7% were specialists and the remaining were residents. The most frequent specialty was internal medicine (37.4%). Israel was the most frequent country of graduation (45.7%), followed by the former Soviet Union (Eastern medical education; 38.4%). The median total score of knowledge was 4 of 10 questions (interquartile range 2-6). A higher score was associated with a Western medical education, being a specialist, shorter elapsed time since graduation, higher number of publications and self-reported reading of ''methods'' and ''discussion'' sections in scientific articles. Conclusion: This study found a low level of knowledge of basic principles of research methods and data analysis among doctors, and this knowledge considerably differed by country of medical school graduation.

While the correlation and chronology of appearance of diabetic nephropathy and retinopathy is well known in diabetes mellitus (DM) type 1 patients, in DM type 2 this correlation is less clear. A retrospective study including 917 patients with type 2 diabetes. Diabetic retinopathy (DR) was diagnosed based on fundus photographs taken with a non-mydriatic camera. Diabetic nephropathy (DN) was diagnosed based on urinary albumin concentration in a morning urine sample. Statistical analysis was performed with a seemingly unrelated regression (SUR) model. Our SUR model is statistically significant: the test for "model versus saturated" is 2.20 and its significance level is 0.8205. The model revealed that creatinine and glomerular filtration rate (GFR) have strong influence on albuminuria, while body mass index (BMI) and HbA1c have less significant impact. DR is affected positively by diabetes duration, insulin treatment, glucose levels, and HbA1c, and it is affected negatively by GFR, triglyceride levels, and BMI. The association between DR and DN was statistically significant and had a unidirectional correlation, which can be explained by chronological order; that is, DN precedes DR. The present study indicates that the level of renal impairment is proportional to the level of damage to the eye. Furthermore, such an association has a chronological aspect; the renal injury precedes retinal damage.

We found that CFD levels correlate well with the extent of ischemic injury, brain edema, and neurologic outcome in rats 24 hours post-MCAO. We have also shown that CFD correlates well with the expected temporal progression of ischemic injury. These findings place CFD in a unique place as a biomarker for stroke, both experimentally and possibly clinically.

Stroke is a major cause of global morbidity and mortality. Middle cerebral artery occlusion (MCAO) has historically been the most common animal model of simulating ischemic stroke. The extent of neurological injury after MCAO is typically measured by cerebral edema, infarct zone, and blood-brain barrier (BBB) permeability. A significant limitation of these methods is that separate sets of brains must be used for each measurement. Here we examine an alternative method of measuring cerebral edema, infarct zone and BBB permeability following MCAO in the same set of brain samples. Ninety-six rats were randomly divided into three experimental groups. Group 1 (n = 27) was used for the evaluation of infarct zone and brain edema in rats post-MCAO (n = 17) vs. sham-operated controls (n = 10). Group 2 (n = 27) was used for the evaluation of BBB breakdown in rats post-MCAO (n = 15) vs. sham-operated controls (n = 10). In Group 3 (n = 42), all three parameters were measured in the same set of brain slices in rats post-MCAO (n = 26) vs. sham-operated controls (n = 16). The effect of Evans blue on the accuracy of measuring infarct zone by 2,3,5-triphenyltetrazolium chloride (TTC) staining was determined by measuring infarct zone with and without an applied blue filter. The effects of various concentrations of TTC (0, 0.05, 0.35, 0.5, 1, and 2%) on the accuracy of measuring BBB permeability was also assessed. There was an increase in infarct volume (p < 0.01), brain edema (p < 0.01) and BBB breakdown (p < 0.01) in rats following MCAO compared to sham-operated controls, whether measured separately or together in the same set of brain samples. Evans blue had an effect on measuring infarct volume that was minimized by the application of a blue filter on scanned brain slices. There was no difference in the Evans blue extravasation index for the brain tissue samples without TTC compared to brain tissue samples incubated in TTC. Our results demonstrate that measuring cerebral edema, infarct zone and BBB permeability following MCAO can accurately be measured in the same set of brain samples.

PURPOSE: To evaluate the safety and efficacy of accelerated contact lens–assisted cross-linking (A-CACXL) for patients with keratoconus and thin corneas. METHODS: This retrospective study included consecutive patients undergoing A-CACXL for progressive keratoconus from 2015 to 2017. Patients with a minimum corneal thickness of 400 µm or less after epithelium removal who underwent A-CACXL (9 mW/cm 2 for 10 minutes, using iso-osmolar 0.1% riboflavin solution and a 90-µm thick, daily disposable bandage soft contact lens) with a follow-up time of 12 months or more were included. The main outcome measures were uncorrected (UDVA) and corrected (CDVA) distance visual acuity and minimum corneal thickness at the last visit. Progression (increase) and flattening (decrease) were defined as a change of 1.00 diopters (D) or greater in maximum keratometry or 1.50 D or greater in mean keratometry. RESULTS: Overall, 24 eyes of 24 patients were included with a follow-up time of 18.2 ± 6.3 months and a mean minimum corneal thickness, after epithelial debridement, of 353.13 µm. There was a significant improvement in UDVA ( P = .009), maximum keratometry ( P = .03), anterior steep keratometry ( P = .04), anterior astigmatism ( P = .02), and posterior astigmatism ( P = .04) with no significant change in minimum corneal thickness ( P = .11). There was a significant improvement in UDVA (0.90 ± 0.63 to 0.64 ± 0.47 logMAR, P = .009), maximum keratometry (61.20 ± 6.30 to 59.90 ± 5.70 D, P = .03), anterior steep keratometry (55.10 ± 3.90 to 54.50 ± 4.10 D, P = .04), anterior astigmatism (5.50 ± 2.40 to 4.60 ± 2.10 D, P = .02), and posterior astigmatism (0.90 ± 0.40 to 0.80 ± 0.40 D, P = .04) with no significant change in minimum corneal thickness (from 399.8 ± 30.7 to 391.0 ± 43.8 μm, P = .11). Flattening occurred in 45.8% (n = 11) and progression in 20.8% (n = 5). There were no serious adverse events. Persistent clinically significant stromal haze occurred in one case and completely resolved by 6 months. There was no significant change in endothelial cell density ( P = .10). CONCLUSIONS: In patients with keratoconus and thin corneas, A-CACXL halted keratoconus progression in 80%, led to flattening in 45%, and significantly improved UDVA and keratometry values without any evidence of damage to the corneal endothelium or permanent adverse events. [ J Refract Surg. 2019;35(10):642–648.]

Our results suggest that accelerated PACK-CXL may provide an antimicrobial effect similar to the 1 low-intensity, slow setting (30 minutes at 3 mW/cm) and may be used as additional treatment in moderate-sized therapy-resistant infectious keratitis.