Loss of Müller's cells and photoreceptors in macular telangiectasia type 2

PURPOSE: To correlate postmortem histology from a patient with macular telangiectasia (MacTel) type 2 with previously recorded clinical imaging data. DESIGN: Observational clinicopathologic case report. METHODS: The distribution of retinal blood vessels was used to map the location of serial wax sections in color fundus and optical coherence tomography (OCT) images. Fluorescent immunohistochemistry was used to visualize markers for Müller's cells (vimentin and retinaldehyde-binding protein 1), photoreceptors (L-M opsin, rhodopsin, and cytochrome oxidase 2), and the outer limiting membrane (OLM) (zonula occludens 1 and occludin). MAIN OUTCOME MEASURES: Distribution of specific markers in immunohistochemistry on retinal sections through the fovea in relation to clinical data. RESULTS: The clinically recorded region of macular pigment loss in the macula correlated well with Müller's cell depletion. The OCT data showed a loss of the photoreceptor inner segment/outer segment (IS/OS) junction in the central retina, which correlated well with rod loss but not with cone loss. Markers for the OLM were lost where Müller's cells were lost. CONCLUSIONS: We have confirmed our previous finding of Müller's cell loss in MacTel type 2 and have shown that the area of Müller's cell loss matches the area of macular pigment depletion. In this patient, the IS/OS junction seen by OCT was absent in a region where rods were depleted but cones were still present

Effect of High Dose Spironolactone and Chlorthalidone in Essential Hypertension: Relation to Plasma Renin Activity and Plasma Volume

The effect on blood pressure of high (400 mg/day-S400) and moderate dose (200 mg/day-S200) spironolactone and chlorthalidone (100 mg/day—C100), given in a random double-blind manner was related to plasma renin activity and plasma volume in 38 essential hypertensives. The fall in pressure from a control of 154/103 mm Hg was essentially the same after four weeks of each drug—S400 ABP 24/13 mm, S200 18/9 mm, C100 17/12 mm (all P < 0–001). Twelve of 37 patients (32%) had low initial renin, but this appeared as responsive to the chlorthalidone stimulus as that of the normal renin group. The anti-hypertensive effect of all regimens was unrelated to plasma renin activity. Plasma volume was significantly lowered at the end of each treatment period, but the decline could not be correlated with blood pressure effects. Patients with initially low plasma volume were more likely to respond to S400 ( r = 0.545, P < 0.01), whereas the anti-hypertensive effect of the S200 and C100 regimens was independent of this variable.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73411/1/j.1445-5994.1975.tb03249.x.pd

Blood pressure crisis following withdrawal of clonidine (Catapres, Catapresan), with special reference to arterial and urinary catecholamine levels, and suggestions for acute management

In five patients with severe essential hypertension, placebo was substituted after 24 to 48 months of treatment with clonidine and a diuretic. In the present study, four of the patients developed a marked blood pressure rise following withdrawal of clonidine which was rapidly reversed by intravenous administration of propranolol 0.2 mg. per kilogram of body weight and phentolamine 20 to 30 mg. The fifth patient was pretreated with reserpine 2.0 mg. intramuscularly for three days prior to withdrawal of clonidine, and the blood pressure rise which he experienced was far less impressive. All patients experienced similar "withdrawal" symptoms, consisting of headaches, insomnia, restlessness, tremor, and nausea.Catecholamines were determined in arterial blood and urine, before and during the overshoot. They revealed a marked increase, particularly in the urine samples, consistent with the appearance of a hyperadrenergic state.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33890/1/0000155.pd

Chronic creatine kinase deficiency eventually leads to congestive heart failure, but severity is dependent on genetic background, gender and age

The creatine kinase (CK) energy transport and buffering system supports cardiac function at times of high demand and is impaired in the failing heart. Mice deficient in muscle- and mitochondrial-CK (M/Mt-CK(−/−)) have previously been described, but exhibit an unexpectedly mild phenotype of compensated left ventricular (LV) hypertrophy. We hypothesised that heart failure would develop with age and performed echocardiography and LV haemodynamics at 1 year. Since all previous studies have utilised mice with a mixed genetic background, we backcrossed for >10 generations on to C57BL/6, and repeated the in vivo investigations. Male M/Mt-CK(−/−) mice on the mixed genetic background developed congestive heart failure as evidenced by significantly elevated end-diastolic pressure, impaired contractility, LV dilatation, hypertrophy and pulmonary congestion. Female mice were less severely affected, only showing trends for these parameters. After backcrossing, M/Mt-CK(−/−) mice had LV dysfunction consisting of impaired isovolumetric pressure changes and reduced contractile reserve, but did not develop congestive heart failure. Body weight was lower in knockout mice as a consequence of reduced total body fat. LV weight was not significantly elevated in relation to other internal organs and gene expression of LVH markers was normal, suggesting an absence of hypertrophy. In conclusion, the consequences of CK deficiency are highly dependent on genetic modifiers, gender and age. However, the observation that a primary defect in CK can, under the right conditions, result in heart failure suggests that impaired CK activity in the failing heart could contribute to disease progression. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00395-012-0276-2) contains supplementary material, which is available to authorized users

Early Pars Plana Vitrectomy for Treatment of Acute Infective Endophthalmitis

Purpose: To evaluate the efficacy and safety of early pars plana vitrectomy (PPV) for the treatment of acute infective endophthalmitis, and identify prognostic factors for better visual outcome. Design: Retrospective cohort study. Methods: Consecutive patients who underwent early PPV within 72 hours of presentation for the treatment of acute infective bacterial endophthalmitis and presented to a large tertiary referral center in New South Wales, Australia, between January 2009 and December 2013 were included. Changes in best-corrected visual acuity (VA) from baseline to 1 year were examined. Results: A total of 64 patients were included. The inciting events were cataract surgery (53%), intravitreal injection (36%), trabeculectomy (3%), and endogenous (3%). The mean VA improved from 3.1 logMAR (hand motion) at baseline to 1.02 (approximately 20/200) at 1 year, with 42% achieving final VA equal to or better than 0.477 logMAR (20/60) following early PPV. Positive prognostic factors were negative microbial cultures (P < 0.01) and etiology of post-cataract surgery (P < 0.01). In multivariable analyses adjusting for age and prognostic factors, patients with baseline VA of light perception and hand motion achieved greater visual gains than those with counting fingers, with gains of logMAR of -2.68, -2.09, and -0.85, respectively (P < 0.0001). Conclusions: Most patients who undergo early PPV experience substantial VA improvement. Negative microbial cultures and endophthalmitis after cataract surgery were associated with better final visual outcome. Patients with presenting VA of light perception or hand motion achieved higher visual gains than those with counting fingers, suggesting the possibility that early PPV may be beneficial in both groups

The role of OCT-A in retinal disease management

Optical coherence tomography angiography (OCT-A) is a non-invasive, non-dye-based imaging modality that has the potential to enhance our understanding of retinal diseases. While this rapidly advancing imaging modality offers great potential, there is a need for community-wide understanding of the range of technologies and methods for interpreting the images, as well as a need to enhance understanding of images from disease-free eyes for reference when screening for retinal diseases. Importantly, clinical trials have been designed without OCT-A-based endpoints; therefore, caution is required when making treatment decisions based on OCT-A imaging alone. With this in mind, a full understanding of the advantages and limitations of OCT-A will be vital for effective development of the technique within the field of ophthalmology. On behalf of the Vision Academy Steering Committee (sponsored by Bayer), this publication summarizes the views of the authors on the current use of OCT-A imaging and explores its potential for future applications in research and clinical practice

Projection of long-term visual acuity outcomes based on initial treatment response in neovascular age-related macular degeneration

PURPOSE To explore various methods for assessing the early response to vascular endothelial growth factor (VEGF) inhibitors for neovascular age-related macular degeneration and investigate their association with 3 year visual acuity (VA) outcomes. DESIGN Observational study from a prospectively collected registry. PARTICIPANTS Treatment-naïve eyes in the Fight Retinal Blindness! outcomes registry that commenced anti-VEGF therapy between 1st January 2007 and 1st March 2014 that received 3 anti-VEGF injections within the first 3 months. METHODS The early response was defined as occurring up until the 4th injection. Various early response metrics, which included both continuous and categorical variables, were explored: 1) achieving good VA (≥70 letters [20/40]), 2) absolute change in VA from baseline, 3) time to first grading of the choroidal neovascular lesion as inactive, 4) maximum rate of VA change between successive injections. MAIN OUTCOME MEASURES Proportion of eyes achieving ≥70 letters at 3 years. RESULTS This study included 2051 treatment-naïve eyes from 1828 patients. Achieving good vision at 3 years was significantly associated with 1) having good vision by the 4th injection (odds ratio [95% CI]: 9.8 [6.5, 14.7] for VA≥70 vs. VA5 letters) early VA gains (1.8 [1.2, 2.6], P = 0.002 and 1.8 [1.3, 2.5], P 3 injections), 4) gradual change (between -4 and 4 letters) or rapid (>5 letters) gains between successive injections (1.7 [1.1, 2.6], P = 0.015 and 1.6 [1.1, 2.3], P = 0.018 for gradual change and rapid gain vs. rapid loss). Eyes that achieved small or large early gains achieved similar vision at 3 years (65.0 and 64.7 letters respectively), and had better vision than eyes with early VA loss (57.2 letters). CONCLUSIONS Attainment of good vision by the 4th injection was strongly associated with 3 year visual outcomes, while other early response parameters had a moderate association. The early response during the initial 3 monthly loading doses can be a useful guide for subsequent treatment decisions