Effects of Lidocaine on Mitomycin C Cytotoxicity

PURPOSE

Intra-Tenon or subconjunctival injection of a solution of mitomycin C (MMC) and 1% preservative-free lidocaine (as an anesthetic) has gained popularity for its use in trabeculectomy, a filtering surgery for glaucoma. To our knowledge, no studies have analyzed the impact of lidocaine on the cytotoxic effects of MMC in this setting. This study was conducted to evaluate in vitro fibroblast cytotoxicity to a solution of MMC (0.2 mg/ml) and 1% preservative-free lidocaine.

DESIGN

Experimental study.

PARTICIPANTS

Nonhuman subject research.

METHODS

Cultured human conjunctival fibroblasts were incubated in phosphate-buffered saline (PBS) (control), MMC (0.2 mg/ml), a mixture of 0.2 mg/ml MMC + 1% preservative-free lidocaine, or 1% preservative-free lidocaine. Samples were taken at 2, 5, 10, 30, and 60 minutes, and a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay with photoabsorbance testing was used to assess conjunctival cell viability.

MAIN OUTCOME MEASURE

Mean photoabsorbance.

RESULTS

Mean photoabsorbance across all time intervals was 0.680 for solutions incubated in PBS, 0.642 for MMC, 0.612 for MMC + 1% preservative-free lidocaine, and 0.605 for 1% preservative-free lidocaine. A 2-way analysis of variance analyzing solution, time, and solution-time interaction on photoabsorbance showed that PBS was least cytotoxic and an optimal control for this study. Tukey post hoc comparisons showed that MMC was more cytotoxic than PBS (P < 0.001). However, both MMC + 1% preservative-free lidocaine and 1% preservative-free lidocaine were more cytotoxic than MMC and PBS (P < 0.01 for all). No significant differences in cytotoxicity comparing lidocaine-containing solutions were observed.

CONCLUSIONS

In this in vitro study, we found an increase in cytotoxicity when MMC (0.2 mg/ml) was combined with 1% preservative-free lidocaine. We note that lidocaine did not inhibit MMC cytotoxicity and exhibited a significant cytotoxic effect on its own.

Association of Dry Eye Disease With Dyslipidemia and Statin Use

PURPOSE

To determine whether an association exists between dry eye disease (DED) and statin use and/or dyslipidemia.

DESIGN

Retrospective, case-control study.

METHODS

Setting: University of North Carolina (UNC)-affiliated healthcare facilities.

STUDY POPULATION

72,931 patients seen at UNC ophthalmology clinics over a 10-year period.

MAIN OUTCOME MEASURES

Odds ratios (ORs) calculated between DED and a history of low, moderate, or high-intensity statin use; and ORs calculated between DED and abnormal lipid panel values.

RESULTS

Total of 39,336 individuals (53.9% female) were analyzed after exclusion of individuals with confounding risk factors for DED. Of these, 3,399 patients (8.6%) carried a diagnosis of DED. Low-, moderate-, and high-intensity statin regimens were used by 751 subjects (1.9%), 2,655 subjects (6.8%), and 1,036 subjects (2.6%). Lipid abnormalities were identified as total cholesterol >200 mg/dL, 4,558 subjects (11.6%); high-density lipoprotein (HDL) <40 mg/dL, 2,078 subjects (5.3%); low-density lipoprotein (LDL) >130 mg/dL, 2,756 subjects (7.0%); and triglycerides (TGs) >150 mg/dL, 2,881 subjects (7.3%). The odds ratios (OR) of carrying a diagnosis of DED given the presence of low-, moderate-, and high-intensity statin use were 1.39 (95% confidence interval [CI]: 1.13-1.72); OR 1.47 (95% CI: 1.30-1.65), and OR 1.46 (95% CI: 1.21-1.75), respectively. The OR of carrying a diagnosis of DED given the presence of total cholesterol >200 mg/dL, HDL <40 mg/dL, LDL >130 mg/dL, and TGs >150 mg/dL were 1.66 (95% CI: 1.52-1.82), 1.45 (95% CI: 1.26-1.67), 1.55 (95% CI: 1.39-1.74), and 1.43 (95% CI: 1.27-1.61), respectively.

CONCLUSIONS

A history of statin use or dyslipidemia is associated with an increased odds of having a DED diagnosis. Further studies are needed to determine whether statin use and/or dyslipidemia increases the risk of DED.

Cataract Surgery Outcomes in Eyes With Primary Epiretinal Membrane

Importance

Primary epiretinal membrane (ERM) is a common retinal disorder with a prevalence of 4% to 18.5%. Although ERM and cataracts commonly occur together, to our knowledge, no studies have investigated the outcome of cataract surgery alone in this setting.

Objective

To analyze the visual outcome and cystoid macular edema risk with cataract surgery in eyes with primary ERM.

Design, Setting, and Participants

In this retrospective clinical database study, data were collected from July 2003 to March 2015 from 8 locations in the United Kingdom. Cataract surgery data of 217 557 eyes were extracted from the electronic medical record of the UK National Health Service. After exclusion of 57 561 eyes with combined surgery, prior vitrectomy, copathology, and complications, 812 eyes with primary ERM and 159 184 reference eyes were analyzed.

Main Outcomes and Measures

We report on visual acuity (VA), the incidence of cystoid macular edema, and the need for ERM surgery.

Results

The mean (SD) age of patients in the ERM group was 73.7 (9.23) years, and 395 of 812 were men (46.8%). The mean (SD) age of patients in the reference group was 74.4 (12.19) years, and 65 265 of 159 184 were men (41%). Epiretinal membrane eyes assessed at 4 to 12 weeks postoperatively gained 0.27 (0.32) logMAR (approximately 3 Snellen lines), with 200 of 448 (44.6%) improving by 0.30 logMAR or more (≥3 Snellen lines) and 32 of 448 (7.1%) worsening by 0.30 logMAR or more. Reference eyes gained a mean (SD) of 0.44 (0.26) logMAR (approximately 4 Snellen lines), with 48 583 of 77 408 (62.8%) improving by 0.30 logMAR or more and 2125 of 77 408 (2.7%) worsening by 0.30 logMAR or more. Although all eyes with preoperative VA of 20/40 or less improved, only reference eyes with preoperative VA of more than 20/40 showed improvement. Cystoid macular edema developed in 57 of 663 ERM eyes (8.6%) (95% CI, 6.69-10.98) and 1731 of 125 435 reference eyes (1.38%) (95% CI, 1.32-1.45) (P < .001). Epiretinal membrane surgery was performed in 43 of 663 (6.5%) ERM eyes.

Conclusions and Relevance

On average, VA improved 0.27 logMAR (approximately 3 Snellen lines) in eyes with ERM. Eyes with ERM and VA of 20/40 or less showed more benefit after cataract surgery than those with better preoperative vision. However, compared with eyes without ERM, higher rates of cystoid macular edema and a lower postoperative VA gain were noted.

Office-based Air-Fluid Exchange for Diabetic Post-Operative Vitreous Cavity Hemorrhage

Post-operative vitreous cavity hemorrhage (POVCH) is observed in 6-75% of eyes undergoing pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR). We describe our technique for office-based Air fluid exchange (AFX) in the treatment of POVCH. Sixteen eyes (15 patients) with PDR and POVCH undergoing office-based AFX between January 2006 and November 2016 were retrospectively identified. The pre- and post- procedure visual acuity (VA) and complications were compared between eyes with and without traction retinal detachment (TRD). Medicare charges for office-based AFX versus PPV were also analyzed. Mean (± standard deviation [SD]) age at the time of AFX was 55.31 (± 8.02) years. Nine eyes (56.25%) had TRD prior to PPV and 11 eyes (68.75%) were pseudophakic. The improvements in mean (±SD) logMAR VA at the last postoperative visit (3 - 8 months) were 1.38 (± 0.99), 0.82 (± 0.91) and 2.09 (± 0.53) in all eyes, TRD eyes and non-TRD eyes, respectively. Complications included cataract progression, hypotony, and recurrence of TRD and ghost cell glaucoma. The total cost of outpatient AFX was $1,409.59 less than that of PPV. Office-based AFX is a cost-effective alternative treatment for non-clearing diabetic POVCH with an acceptable risk profile.

Correction: Arterial tortuosity syndrome: 40 new families and literature review

In the published version of this paper the author Neus Baena's name was incorrectly given as Neus Baena Diez. This has now been corrected in both the HTML and PDF versions of the paper.

A unique case series of autosomal recessive bestrophinopathy exhibiting multigenerational inheritance

INTRODUCTION

Autosomal recessive bestrophinopathy (ARB) is a retinal disease caused by biallelic mutations of the BEST1 gene. It has a variable phenotype with white flecks in the retina, multifocal yellow subretinal deposits, macular edema, choroidal neovascularization, hyperopia, and electrophysiological abnormalities. We describe a family with ARB and multigenerational inheritance.

METHODS

Three generations of a Middle Eastern family (a woman, one son, and two grandchildren) were evaluated by our ocular genetics team. Eye examinations, fundus photography, and optical coherence tomography (OCT) were performed. Genetic testing was obtained on examined patients and available relatives.

RESULTS

The proband demonstrated counting fingers vision and white flecks in the retinal periphery, with macular subretinal fluid (SRF), loss of outer photoreceptor segments, and epiretinal membrane (ERM) on OCT. Two grandchildren demonstrated decreased vision, multifocal yellow subretinal deposits, and SRF on OCT. Two grandchildren examined elsewhere were reported to be similarly affected. A son's examination was normal except for extra-macular scars (from prior toxoplasmosis) and ERM. Genetic history revealed consanguinity and testing showed homozygosity for BEST1 mutations in the proband and two grandchildren c.473G>A/c.473G>A (R218H /R218H) and heterozygosity in two unaffected sons and two unaffected daughters-in-law c.473G>A/WT (p.R218H/WT).

DISCUSSION

We present a consanguineous family of five affected individuals with ARB and four confirmed carriers. Their pedigree was consistent with dominant inheritance and incomplete penetrance. Genetic testing clarified the diagnosis and mode of inheritance. We describe the genetic findings, phenotypic variability, and recessive inheritance of an often dominantly inherited mutation as notable elements in their case.

A variance-stabilizing transformation for gene-expression microarray data

MOTIVATION

Standard statistical techniques often assume that data are normally distributed, with constant variance not depending on the mean of the data. Data that violate these assumptions can often be brought in line with the assumptions by application of a transformation. Gene-expression microarray data have a complicated error structure, with a variance that changes with the mean in a non-linear fashion. Log transformations, which are often applied to microarray data, can inflate the variance of observations near background.

RESULTS

We introduce a transformation that stabilizes the variance of microarray data across the full range of expression. Simulation studies also suggest that this transformation approximately symmetrizes microarray data.

Pharmacodynamics of a monoclonal antiphencyclidine Fab with broad selectivity for phencyclidine-like drugs

The development of treatment strategies for drug intoxication has been hindered in part by the lack of clinically useful antagonists. Consequently, the major goal of these studies was to determine whether a monoclonal antibody Fab fragment (of IgG) could be used as an effective drug class-selective antagonist and to understand better the dose-response relationships for reversing CNS drug toxicity. Changes in drug-induced locomotor effects in a rat model were used to assess the ability of the antiphencyclidine (anti-PCP) Fab to reverse the behavioral effects of PCP and other potent arylcyclohexylamines. In experiments to determine the pharmacodynamics of Fabinduced antagonism of behavioral effects, the Fab completely reversed all PCP-induced locomotor effects in a Fab dose-dependent manner with a minimal effective dose of 0.18 mole-equivalents of Fab and an ED50 value of about one-third mole-equivalent. The anti-PCP Fab also completely reversed the locomotor effects induced by two other structurally related potent analogs of PCP: 1-[1-(2-thienyl)cyclohexyl]piperidine and N-ethyl-1-phenylcyclohexylamine. In addition, pharmacological and immunological selectivity was further tested by treatment of the behavioral effects induced by the structurally unrelated locomotor stimulant (+)methamphetamine. The antibody did not effectively reverse the effects of methamphetamine-induced locomotor activity. These results indicate that antibody-based medications can be developed to treat toxicity caused by classes of drugs as well as by individual drugs.