Publications

2017

PURPOSE: Obstructive meibomian gland dysfunction is a leading cause of ocular morbidity and its treatment remains a challenge. Meibomian gland probing was initially described in 2010. Here, the authors describe a modified technique, dynamic intraductal meibomian probing, which offers several advantages over the traditional approach including increased magnification, greater eyelid stabilization, enhanced anesthesia, and easier identification of gland orifices through the expression of meibum. METHODS: The authors conducted a retrospective chart review of 70 eyelids with treatment-resistant obstructive meibomian gland dysfunction undergoing dynamic intraductal meibomian probing between January 2013 and April 2015. RESULTS: Immediately after the procedure, 91.4% of cases experienced symptomatic improvement, and no complications were noted. CONCLUSIONS: Dynamic intraductal meibomian probing is an effective and safe treatment for obstructive meibomian gland dysfunction that is resistant to traditional therapies.

Turalba A, Cakiner-Egilmez T, Payal A, Gonzalez-Gonzalez L, Chomsky A, Vollman D, Baze E, Lawrence M, Daly M. Outcomes after cataract surgery in eyes with pseudoexfoliation: Results from the Veterans Affairs Ophthalmic Surgery Outcomes Data Project. Can J Ophthalmol. 2017;52(1):61–68.

OBJECTIVE: To compare clinical outcomes of cataract surgery in eyes with and without pseudoexfoliation (PXF). DESIGN: Retrospective deidentified data analysis. PARTICIPANTS: A total of 123 PXF and 4776 non-PXF eyes of patients who underwent cataract surgery. METHODS: We compared data on visual acuity, Visual Function Questionnaire (VFQ)-based quality of life, and complications in PXF and non-PXF eyes from the Veterans Affairs (VA) Ophthalmic Surgery Outcomes Data Project across 5 VA medical centres. RESULTS: Pupillary expansion devices were used in 31 (25.2%) PXF cases and 398 (8.4%) non-PXF cases (p < 0.0001). Capsular tension rings were used in 6 (4.9%) PXF cases and 55 (1.2%) non-PXF cases (p < 0.004). The following complications occurred more frequently in PXF cases: zonular dehiscence without vitrectomy (4 [3.3%] PXF cases vs 40 [0.8%] non-PXF cases p = 0.02), persistent inflammation (28 [24.1%] vs 668 [14.5%]; p = 0.007), and persistent intraocular pressure elevation (5 [4.3%] vs 68 [1.5%]; p = 0.03). Best corrected visual acuity (BCVA) improved in both groups after 1 month, but 87 (83.7%) PXF cases achieved postoperative BCVA better than or equal to 20/40 compared to 3991 (93.8%) non-PXF cases (p = 0.0003). There was no significant difference in the postoperative composite VFQ scores between PXF (82.1 ± 16.9) and non-PXF cases (84.2 ± 16.8, p = 0.09). CONCLUSIONS: Several complications occurred more frequently in the PXF group compared to the non-PXF group, and fewer PXF cases achieved BCVA better than or equal to 20/40. Despite this, both groups experienced similar improvement in vision-related quality of life after cataract surgery.

Enterococci are ancient commensal bacteria that recently emerged as leading causes of antibiotic-resistant, hospital-acquired infection. Vancomycin-resistant enterococci (VRE) epitomize why drug-resistant enterococcal infections are a problem: VRE readily colonize the antibiotic-perturbed gastrointestinal (GI) tract where they amplify to large numbers, and from there, they infect other body sites, including the bloodstream, urinary tract, and surgical wounds. VRE are resistant to many antimicrobials and host defenses, which facilitates establishment at the site of infection and confounds therapeutic clearance. Having evolved to colonize the GI tract, VRE are comparatively ill adapted to the human bloodstream. A recent study by Honsa and colleagues (E. S. Honsa et al., mBio 8:e02124-16, 2017, https://doi.org/10.1128/mBio.02124-16) found that a strain of vancomycin-resistant Enterococcus faecium evolved antibiotic tolerance within the bloodstream of an immunocompromised host by activating the stringent response through mutation of relA Precisely how VRE colonize and infect and the selective pressures that led to the outgrowth of relA mutants are the subjects of ongoing research.

Wang R, Seifert P, Jakobs T. Astrocytes in the Optic Nerve Head of Glaucomatous Mice Display a Characteristic Reactive Phenotype. Invest Ophthalmol Vis Sci. 2017;58(2):924–932.

Purpose: Optic nerve head astrocytes, a subtype of white-matter astrocytes, become reactive early in the course of glaucoma. It was shown recently that in the DBA/2J mouse model of inherited glaucoma optic nerve astrocytes extend new longitudinal processes into the axon bundles before ganglion cell loss becomes apparent. The present study aims at testing whether this behavior of astrocytes is typical of early glaucomatous damage. Methods: Mice expressing green fluorescent protein in individual astrocytes were used to evaluate the early response of astrocytes in the glial lamina of the optic nerve head after increasing the IOP using the microbead occlusion method. Tissue sections from the glial lamina were imaged consecutively by confocal and electron microscopy. Results: Confocal and electron microscope images show that astrocytes close to the myelination transition zone in the hypertensive nerve heads extend new processes that follow the longitudinal axis of the optic nerve and invade axon bundles in the nerve head. Ultrastructurally, the longitudinal processes were largely devoid of subcellular organelles except for degenerating mitochondria. Conclusions: The longitudinal processes are a common feature of glaucomatous optic nerve astrocytes, whereas they are not observed after traumatic nerve injury. Thus, astrocytes appear to fine-tune their responses to the nature and/or timing of the injury to the neurons that they surround.

You C, Lamba N, Lasave A, Ma L, Diaz MH, Foster S. Rituximab in the treatment of ocular cicatricial pemphigoid: a retrospective cohort study. Graefes Arch Clin Exp Ophthalmol. 2017;255(6):1221–1228.
PURPOSE: The purpose was to evaluate the effectiveness and safety of rituximab (RTX) for the treatment of patients with aggressive ocular cicatricial pemphigoid (OCP). METHODS: A review of patient records at a tertiary referral center with biopsy confirmed OCP who presented between 2006 and 2016. Sixty-one eyes of 32 patients with symptomatic OCP who received treatment with RTX monotherapy or RTX in combination with additional immunomodulatory treatment (IMT) were evaluated. Main outcomes included clinically evident remission of disease, the percentage of corticosteroid sparing patients, stage of OCP (Foster), best corrected visual acuity, and treatment complications. Remission was defined as absence of progressive scarring and active ocular inflammation for ≥ 2 months. Partial remission/responding was defined as disease control and clinical improvement for ≥ 2 months. RESULTS: Mean age at the initiation of RTX treatment was 59.1 years (range, 24-80 years) with a median follow-up time after RTX initiation of 32 months (range, 14 to 127 months). Twenty-six patients achieved clinical remission with an average sustained remission of 24.5 months (from 9 months to 84 months). RTX monotherapy was used in six patients, RTX in combination with intravenous immunoglobulin in 14 patients, and RTX with intravenous immunoglobulin and/or with other IMT agent in six patients. Seven eyes (11.5%) of six patients had favorable response to RTX and achieved response and partial remission, while inflammation remained active in the other seven eyes (11.5%) of four patients though there was no progressive scarring. At the last visit, three patients (9.4%) were on topical corticosteroid, three patients (9.4%) were treated with systemic corticosteroid treatments, and the other 26 patients (81.2%) achieved corticosteroid sparing therapy. Five eyes (8.2%) progressed one Foster stage. No other cicatrization progression or worsening of LogMAR visual acuity (p = 0.641) was observed during the follow-up period. Adverse events included leukopenia in three patients (9.4%), anemia in two patients (6.2%), liver enzyme elevation in three patients (9.4%) who were also on another concomitant IMT drug, and Epstein-Barr Virus infection and sinus infection in one patient each (3.1%). No other severe adverse events were noted during the follow-up period. CONCLUSIONS: These retrospective data suggest that RTX is efficacious and well tolerated when included for the treatment of OCP. Controlled studies are necessary to identify the role of this IMT agent in the therapeutic arsenal, especially its optimum dose and duration of administration.
Huang X, Zhou G, Wu W, Ma G, D’Amore P, Mukai S, Lei H. Editing VEGFR2 Blocks VEGF-Induced Activation of Akt and Tube Formation. Invest Ophthalmol Vis Sci. 2017;58(2):1228–1236.

Purpose: Vascular endothelial growth factor receptor 2 (VEGFR2) plays a key role in VEGF-induced angiogenesis. The goal of this project was to test the hypothesis that editing genomic VEGFR2 loci using the technology of clustered regularly interspaced palindromic repeats (CRISPR)-associated DNA endonuclease (Cas)9 in Streptococcus pyogenes (SpCas9) was able to block VEGF-induced activation of Akt and tube formation. Methods: Four 20 nucleotides for synthesizing single-guide RNAs based on human genomic VEGFR2 exon 3 loci were selected and cloned into a lentiCRISPR v2 vector, respectively. The DNA fragments from the genomic VEGFR2 exon 3 of transduced primary human retinal microvascular endothelial cells (HRECs) were analyzed by Sanger DNA sequencing, surveyor nuclease assay, and next-generation sequencing (NGS). In the transduced cells, expression of VEGFR2 and VEGF-stimulated signaling events (e.g., Akt phosphorylation) were determined by Western blot analyses; VEGF-induced cellular responses (proliferation, migration, and tube formation) were examined. Results: In the VEGFR2-sgRNA/SpCas9-transduced HRECs, Sanger DNA sequencing indicated that there were mutations, and NGS demonstrated that there were 83.57% insertion and deletions in the genomic VEGFR2 locus; expression of VEGFR2 was depleted in the VEGFR2-sgRNA/SpCas9-transduced HRECs. In addition, there were lower levels of Akt phosphorylation in HRECs with VEGFR2-sgRNA/SpCas9 than those with LacZ-sgRNA/SpCas9, and there was less VEGF-stimulated Akt activation, proliferation, migration, or tube formation in the VEGFR2-depleted HRECs than those treated with aflibercept or ranibizumab. Conclusions: The CRISPR-SpCas9 technology is a potential novel approach to prevention of pathologic angiogenesis.

Jakobiec F, Zakka F, Tu Y, Freitag S. Dermatofibroma of the Eyelid: Immunohistochemical Diagnosis. Ophthal Plast Reconstr Surg. 2017;33(6):e134-e138.
A 66-year-old man developed a painless 2 mm to 3 mm recurrent nodule at the left upper eyelid margin. Excision disclosed a spindle cell lesion without frank atypia or mitotic activity growing in a twisted fascicular pattern often referred to as storiform. All the surgical margins were involved with tumor. Immunohistochemistry demonstrated that many of the constituent spindle and dendritic tumor cells were CD34, factor XIIIa, and CD 163, the latter 2 being biomarkers for monocytic lineage. The lesion was diagnosed as a dermatofibroma rather than a fibrous histiocytoma, a term that should be reserved for more aggressive lesions of deeper fascial planes. Facial dermatofibromas are rarer and more likely than those of the extremities to recur and therefore deserve wider local excision at first surgery with careful and frequent clinical follow ups. Eyelid dermatofibroma has probably often been misdiagnosed as another tumor in the past. Immunohistochemistry can supply valuable biomarker criteria for diagnosis.
PURPOSE: To evaluate changes in corneal endothelial cell density over time in patients with dry eye disease (DED) and to correlate endothelial cell loss with corneal subbasal nerve density. METHODS: This retrospective study included 40 eyes of 20 patients with DED. Laser in vivo confocal microscopy had been performed in the central cornea of both eyes at an initial visit and repeated after a mean follow-up of 33.2 ± 10.2 months. The densities of corneal endothelial cells and subbasal nerves were measured in both visits and compared with 13 eyes of 13 normal age-matched controls. RESULTS: At the initial visit, the DED group had lower densities of corneal endothelial cells (2620 ± 386 cells/mm) and subbasal nerves (17.8 ± 7.5 mm/mm) compared with the control group (2861 ± 292 cells/mm and 22.8 ± 3.0 mm/mm, with P = 0.08 and P = 0.01, respectively). At the end of follow-up, although there was no significant change in subbasal nerve density (16.7 ± 7.2 mm/mm, P = 0.43), the mean corneal endothelial cell density significantly decreased to 2465 ± 391 cells/mm (P = 0.01), with a mean corneal endothelial cell loss of 2.1 ± 3.6% per year. The endothelial cell loss showed a statistically significant negative correlation with the initial subbasal nerve density (Rs = -0.55, P = 0.02). CONCLUSIONS: Patients with DED have an accelerated corneal endothelial cell loss compared with that reported in the literature for normal aging. Those with lower subbasal nerve density, in particular, are at a higher risk for endothelial cell loss over time.
Kim EC, Toyono T, Berlinicke C, Zack D, Jurkunas U, Usui T, Jun A. Screening and Characterization of Drugs That Protect Corneal Endothelial Cells Against Unfolded Protein Response and Oxidative Stress. Invest Ophthalmol Vis Sci. 2017;58(2):892–900.

Purpose: To screen for and characterize compounds that protect corneal endothelial cells against unfolded protein response (UPR) and oxidative stress. Methods: Bovine corneal endothelial cells (BCECs) were treated for 48 hours with 640 compounds from a Food and Drug Administration (FDA)-approved drug library and then challenged with thapsigargin or H2O2 to induce UPR or oxidative stress, respectively. Cell viability was measured using the CellTiter-Glo survival assay. Selected "hits" were subjected to further dose-response testing, and their ability to modulate expression of UPR and oxidative stress markers was assessed by RT-PCR, Western blot, and measurement of protein carbonyl and 8-hydroxydeoxyguanosine (8-OHdG) adducts in immortalized human corneal endothelial cells (iHCECs). Results: Forty-one drugs at 20 μM and 55 drugs at 100 μM increased survival of H2O2-challenged cells, and 8 drugs at 20 μM and 2 drugs at 100 μM increased survival of thapsigargin-challenged cells, compared with untreated control cells. Nicergoline, ergothioneine, nimesulide, oxotremorine, and mefenamic acid increased survival of both H2O2- and thapsigargin-challenged cells. Oxotremorine altered DNA damage inducible 3 (CHOP) gene expression, glucose-regulated protein 78 kDa (GRP78) and activating transcription factor 4 (ATF4) protein expression, and protein carbonyl and 8-OHdG levels. Mefenamic acid altered GRP78 protein expression and protein carbonyl and 8-OHdG levels. Conclusions: Oxotremorine and mefenamic acid are potential survival factors for corneal endothelial cells under UPR and oxidative stress. The described assay can be further expanded to screen additional drugs for potential therapeutic effect in corneal endothelial diseases such as Fuchs' endothelial corneal dystrophy.