2013

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Palioura S, Kim B, Dohlman CH, Chodosh J. The Boston keratoprosthesis type I in mucous membrane pemphigoid. Cornea 2013;32(7):956-61.Abstract
PURPOSE: To evaluate the use of the Boston keratoprosthesis type I implantation in patients with mucous membrane pemphigoid (MMP). METHODS: Retrospective review of 8 eyes of 8 patients with severe ocular surface disease and corneal blindness as a result of MMP who underwent Boston keratoprosthesis type I implantation at the Massachusetts Eye and Ear Infirmary from January 1, 2000, through December 31, 2009. The main outcome measures were best-corrected visual acuity, keratoprosthesis retention, and postoperative complications. RESULTS: The mean age of patients was 71.3 years (range, 55-94 years), and the mean duration of their disease preoperatively was 6.1 years (range, 1.7-11.4 years). Visual acuity after the surgery improved to 20/200 or better in 6 eyes (75%) and to 20/40 or better in 3 eyes (37.5%). Only 1 of 6 eyes (16.7%) was able to maintain visual acuity of 20/200 or better over a mean follow-up period of 3.2 years. Five of the 8 Boston keratoprosthesis type I devices (62.5%) extruded or had to be replaced during a mean follow-up time of 1.7 ± 1.7 years. Loss of vision to worse than 20/200 during the follow-up period occurred because of keratoprosthesis type I extrusion, end-stage glaucoma, and retinal or choroidal detachment. CONCLUSIONS: The clinical outcomes of Boston keratoprosthesis type I implantation in MMP are guarded and, as judged from the literature, less favorable than those with the Boston keratoprosthesis type II for the same disease.
Palioura S, Chodosh J, Pineda R. A novel approach to the management of a progressive Descemet membrane tear in a patient with keratoglobus and acute hydrops. Cornea 2013;32(3):355-8.Abstract
PURPOSE: To report a case of corneal hydrops in a patient with keratoglobus that was managed with endothelial keratoplasty to achieve corneal stability and prevent a limbus-to-limbus tear in Descemet membrane. METHODS: A 30-year-old man with keratoglobus presented with corneal hydrops in his left eye resulting from a central vertical tear in Descemet membrane. His other eye had been previously treated with penetrating keratoplasty using a large graft (an 11-mm donor graft to a 10-mm recipient bed) because of a limbus-to-limbus tear in Descemet membrane without resolution of his edema. An attempt to approximate the edges of the Descemet tear in the left eye by an intracameral air injection failed, and the tear continued to progress peripherally. An endothelial keratoplasty button with anchoring sutures was placed over the Descemet tear because of excessive localized edema. RESULTS: One month after insertion of the sutured endothelial keratoplasty button, the edema had resolved, and 1 year later, the tear remains sealed. The patient's visual acuity improved from counting fingers at 1 foot to 20/100. CONCLUSIONS: Reconstitution of the posterior corneal surface in keratoglobus-induced hydrops can be achieved with endothelial keratoplasty over the Descemet tear. Preventing progression of a central Descemet tear is essential to bypass the need for a large-diameter penetrating keratoplasty graft and its complications in a young patient with a history of bilateral corneal hydrops.
Panou N, Kim IK, Sobrin L. Choroiditis and choroidal neovascularization in acute disseminated encephalomyelitis. Retin Cases Brief Rep 2013;7(1):89-90.Abstract
PURPOSE: To present a case with bilateral choroidal neovascularization (CNV) secondary to acute disseminated encephalomyelitis-associated choroiditis requiring immunomodulatory therapy for prevention of recurrence. METHODS: The clinical course of a patient diagnosed with acute disseminated encephalomyelitis, who developed bilateral choroiditis at the time of his neurologic diagnosis and bilateral CNV 6 years later, is reviewed. PATIENT: A 57-year-old man developed CNV in both eyes, 6 years after the initial diagnosis of acute disseminated encephalomyelitis-associated choroiditis. The patient was initially treated successfully with intravitreal bevacizumab injections and oral prednisone, but CNV recurred with steroid tapering. Mycophenolate mofetil was initiated as steroid-sparing immunomodulatory therapy. RESULTS: There was no CNV recurrence for 1.5 years without the need for additional antiangiogenic therapy. CONCLUSION: To our best knowledge, this is the first report of choroiditis and secondary CNV associated with acute disseminated encephalomyelitis. In cases of recurrent CNV associated with choroiditis, systemic therapy should be strongly considered in conjunction with antiangiogenic therapy. The recurrence of CNV with tapering of oral steroids and the remission of CNV with steroid-sparing immunomodulatory therapy support the role of ongoing inflammation in the pathogenesis.
Papakostas TD, Lessell S. Teaching video neuroimages: pulsatile proptosis. Neurology 2013;81(21):e160.Abstract
A 44-year-old man with neurofibromatosis type 1 had been aware that his right eye pulsated. His visual acuity was 20/15 in both eyes and his intraocular pressures were normal. He had 4 mm of right exophthalmos and there was pulse-synchronous pulsation of the right eye (video on the Neurology® Web site at www.neurology.org). No bruit was heard. Lisch nodules were present on both irides. CT showed a large osseous defect of the greater wing of the right sphenoid bone. The differential diagnosis of pulsatile proptosis includes absence of the sphenoid wing in patients with neurofibromatosis 1,(1) carotid-cavernous fistula, orbital roof fractures, and arteriovenous malformations.(2.)
Papakostas TD, Lee GN, Lefebvre DR, Barshak MB, Freitag SK. Endogenous panophthalmitis with orbital cellulitis secondary to Escherichia coli. Clin Exp Ophthalmol 2013;41(7):716-8.
Pasquale LR, Loomis SJ, Kang JH, Yaspan BL, Abdrabou W, Budenz DL, Chen TC, Delbono E, Friedman DS, Gaasterland D, Gaasterland T, Grosskreutz CL, Lee RK, Lichter PR, Liu Y, McCarty CA, Moroi SE, Olson LM, Realini T, Rhee DJ, Schuman JS, Singh K, Vollrath D, Wollstein G, Zack DJ, Allingham RR, Pericak-Vance MA, Weinreb RN, Zhang K, Hauser MA, Richards JE, Haines JL, Wiggs JL. CDKN2B-AS1 genotype-glaucoma feature correlations in primary open-angle glaucoma patients from the United States. Am J Ophthalmol 2013;155(2):342-353.e5.Abstract
PURPOSE: To assess the association between single nucleotide polymorphisms (SNPs) of the gene region containing cyclin-dependent kinase inhibitor 2B antisense noncoding RNA (CDKN2B-AS1) and glaucoma features among primary open-angle glaucoma (POAG) patients. DESIGN: Retrospective observational case series. METHODS: We studied associations between 10 CDKN2B-AS1 SNPs and glaucoma features among 976 POAG cases from the Glaucoma Genes and Environment (GLAUGEN) study and 1971 cases from the National Eye Institute Glaucoma Human Genetics Collaboration (NEIGHBOR) consortium. For each patient, we chose the feature from the eye with the higher value. We created cohort-specific multivariable models for glaucoma features and then meta-analyzed the results. RESULTS: For 9 of the 10 protective CDKN2B-AS1 SNPs with minor alleles associated with reduced disease risk (eg, the G allele at rs2157719), POAG patients carrying these minor alleles had smaller cup-to-disc ratio (0.05 units smaller per G allele at diagnosis; 95% CI: -0.08, -0.03; P = 6.23E-05) despite having higher intraocular pressure (IOP) (0.70 mm Hg higher per G allele at DNA collection; 95% CI: 0.40, 1.00; P = 5.45E-06). For the 1 adverse rs3217992 SNP with minor allele A associated with increased disease risk, POAG patients with A alleles had larger cup-to-disc ratio (0.05 units larger per A allele at diagnosis; 95% CI: 0.02, 0.07; P = 4.74E-04) despite having lower IOP (-0.57 mm Hg per A allele at DNA collection; 95% CI: -0.84, -0.29; P = 6.55E-05). CONCLUSION: Alleles of CDKN2B-AS1 SNPs, which influence risk of developing POAG, also modulate optic nerve degeneration among POAG patients, underscoring the role of CDKN2B-AS1 in POAG.
Pasquale LR, Brusie S. The blue arc entoptic phenomenon in glaucoma (an American ophthalmological thesis). Trans Am Ophthalmol Soc 2013;111:46-55.Abstract
PURPOSE: To determine whether the blue arc entoptic phenomenon, a positive visual response originating from the retina with a shape that conforms to the topology of the nerve fiber layer, is depressed in glaucoma. METHODS: We recruited a cross-sectional, nonconsecutive sample of 202 patients from a single institution in a prospective manner. Subjects underwent full ophthalmic examination, including standard automated perimetry (Humphrey Visual Field 24-2) or frequency doubling technology (Screening C 20-5) perimetry. Eligible patients viewed computer-generated stimuli under conditions chosen to optimize perception of the blue arcs. Unmasked testers instructed patients to report whether they were able to perceive blue arcs but did not reveal what response was expected. We created multivariable logistic regression models to ascertain the demographic and clinical parameters associated with perceiving the blue arcs. RESULTS: In multivariable analyses, each 0.1 unit increase in cup-disc ratio was associated with 36% reduced likelihood of perceiving the blue arcs (odds ratio [OR] = 0.66 [95% confidence interval (CI): 0.53-0.83], P<.001). A smaller mean defect was associated with an increased likelihood of perceiving the blue arcs (OR=1.79 [95% CI: 1.40-2.28]); P<.001), while larger pattern standard deviation (OR=0.72 [95% CI: 0.57-0.91]; P=.005) and abnormal glaucoma hemifield test (OR=0.25 [0.10-0.65]; P=.006) were associated with a reduced likelihood of perceiving them. Older age and media opacity were also associated with an inability to perceive the blue arcs. CONCLUSION: In this study, the inability to perceive the blue arcs correlated with structural and functional features associated with glaucoma, although older age and media opacity were also predictors of this entoptic response.
Pasquale LR, Loomis SJ, Weinreb RN, Kang JH, Yaspan BL, Bailey JC, Gaasterland D, Gaasterland T, Lee RK, Scott WK, Lichter PR, Budenz DL, Liu Y, Realini T, Friedman DS, McCarty CA, Moroi SE, Olson L, Schuman JS, Singh K, Vollrath D, Wollstein G, Zack DJ, Brilliant M, Sit AJ, Christen WG, Fingert J, Kraft P, Zhang K, Allingham RR, Pericak-Vance MA, Richards JE, Hauser MA, Haines JL, Wiggs JL. Estrogen pathway polymorphisms in relation to primary open angle glaucoma: an analysis accounting for gender from the United States. Mol Vis 2013;19:1471-81.Abstract
PURPOSE: Circulating estrogen levels are relevant in glaucoma phenotypic traits. We assessed the association between an estrogen metabolism single nucleotide polymorphism (SNP) panel in relation to primary open angle glaucoma (POAG), accounting for gender. METHODS: We included 3,108 POAG cases and 3,430 controls of both genders from the Glaucoma Genes and Environment (GLAUGEN) study and the National Eye Institute Glaucoma Human Genetics Collaboration (NEIGHBOR) consortium genotyped on the Illumina 660W-Quad platform. We assessed the relation between the SNP panels representative of estrogen metabolism and POAG using pathway- and gene-based approaches with the Pathway Analysis by Randomization Incorporating Structure (PARIS) software. PARIS executes a permutation algorithm to assess statistical significance relative to the pathways and genes of comparable genetic architecture. These analyses were performed using the meta-analyzed results from the GLAUGEN and NEIGHBOR data sets. We evaluated POAG overall as well as two subtypes of POAG defined as intraocular pressure (IOP) ≥22 mmHg (high-pressure glaucoma [HPG]) or IOP <22 mmHg (normal pressure glaucoma [NPG]) at diagnosis. We conducted these analyses for each gender separately and then jointly in men and women. RESULTS: Among women, the estrogen SNP pathway was associated with POAG overall (permuted p=0.006) and HPG (permuted p<0.001) but not NPG (permuted p=0.09). Interestingly, there was no relation between the estrogen SNP pathway and POAG when men were considered alone (permuted p>0.99). Among women, gene-based analyses revealed that the catechol-O-methyltransferase gene showed strong associations with HTG (permuted gene p≤0.001) and NPG (permuted gene p=0.01). CONCLUSIONS: The estrogen SNP pathway was associated with POAG among women.
Patel MM, Stacy RC. Paraneoplastic dermatomyositis related to a chondrosarcoma involving the cavernous sinus. J Neuroophthalmol 2013;33(4):363-6.Abstract
Approximately one third of all cases of dermatomyositis may be associated with malignancy. We describe a patient with unexplained rash, joint pain, and muscle weakness, who subsequently developed a cavernous sinus syndrome due to a central nervous system chondrosarcoma. Discovery of this tumor and further dermatologic evaluation, including skin biopsy, resulted in diagnosis of paraneoplastic dermatomyositis due to cavernous sinus chondrosarcoma.
Patel M, Vavvas DG. Fundus autofluorescence in ampiginous choroiditis. Ophthalmic Surg Lasers Imaging Retina 2013;44(4):393-7.Abstract
Fundus autofluorescence (FAF) is being increasingly employed in the evaluation of retinal diseases. We report the first description of FAF findings during the natural history of ampiginous choroiditis and correlate these findings to fundus photography, infrared imaging, and cross-sectional optical coherence tomography. In a patient with a 12-month recurring, relapsing course of ampiginous choroiditis, there was a predictable pattern of FAF findings. At the time of presentation with a whitish-yellow, creamy clinical lesion, FAF reveals a diffuse, subtle hyperautofluorescence at the site of activity. As the clinical lesion fades, the FAF takes on a more intense, discrete, coalesced hyperautofluorescence, which decreases and becomes stippled over time, eventually giving way to a patch of hypoautofluorescence at the site of inactivity. Examination over the patient's long course suggests that FAF evolves predictably during exacerbations and remissions, and the FAF findings reveal activity well after the clinical lesion resolves. FAF is a simple, noninvasive, and effective modality for following the evolution of ampiginous choroiditis.
Patel MM, Jakobiec FA, Zakka FR, Du R, Annino DJ, Borboli-Gerogiannis S, Daniels AB. Intraorbital metastasis from solitary fibrous tumor. Ophthalmic Plast Reconstr Surg 2013;29(3):e76-9.Abstract
Solitary fibrous tumor (SFT) is a rare spindle cell tumor of mesenchymal origin that usually arises from pleura or pericardium but can also arise from many extraserosal sites. Although more than 50 cases of primary SFT of the orbit have been reported, there are no reports to date of a malignant nonophthalmic SFT metastasizing in the orbital soft tissues (although sphenoid wing bony involvement has been reported). The authors report here the first case of a patient with intraorbital metastasis of a CD34-positive malignant SFT. The patient was a 57-year-old man with a history of malignant pleural SFT and a prior kidney metastasis. He presented with the rapid appearance of proptosis and massive conjunctival chemosis preventing eyelid closure, and he was found to have a well-circumscribed metastasis to his lateral rectus muscle. Surgical excision cured his ocular symptoms, although he died 3 months later from brain and widespread metastases.
Patel MM, Lefebvre DR, Lee GN, Brachtel E, Rizzo J, Freitag SK. Gaze-evoked amaurosis from orbital breast carcinoma metastasis. Ophthalmic Plast Reconstr Surg 2013;29(4):e98-e101.Abstract
Gaze-evoked amaurosis (GEA) is a transient monocular vision loss provoked by eccentric gaze. Gaze-evoked amaurosis has been associated with a variety of orbital lesions, most commonly optic nerve sheath meningiomas and cavernous hemangiomas. The authors describe the first report in the literature of GEA as the presenting symptom of an orbital metastasis. The patient was a 47-year-old woman with a history of breast cancer with no known history of metastasis or active disease who presented with several weeks of vision loss in the OD upon rightward gaze. She was found to have enophthalmos and optic disc edema of the OD. Imaging revealed an intraorbital lesion, and a biopsy was consistent with a scirrhous metastasis of her breast carcinoma. This case highlights the importance of considering orbital metastases among the differential for gaze-evoked amaurosis.
Pennock S, Kim D, Mukai S, Kuhnle M, Chun DW, Matsubara J, Cui J, Ma P, Maberley D, Samad A, Van Geest RJ, Oberstein SL, Schlingemann RO, Kazlauskas A. Ranibizumab is a potential prophylaxis for proliferative vitreoretinopathy, a nonangiogenic blinding disease. Am J Pathol 2013;182(5):1659-70.Abstract
Proliferative vitreoretinopathy (PVR) exemplifies a disease that is difficult to predict, lacks effective treatment options, and substantially reduces the quality of life of an individual. Surgery to correct a rhegmatogenous retinal detachment fails primarily because of PVR. Likely mediators of PVR are growth factors in vitreous, which stimulate cells within and behind the retina as an inevitable consequence of a breached retina. Three classes of growth factors [vascular endothelial growth factor A (VEGF-A), platelet-derived growth factors (PDGFs), and non-PDGFs (growth factors outside of the PDGF family)] are relevant to PVR pathogenesis because they act on PDGF receptor α, which is required for experimental PVR and is associated with this disease in humans. We discovered that ranibizumab (a clinically approved agent that neutralizes VEGF-A) reduced the bioactivity of vitreous from patients and experimental animals with PVR, and protected rabbits from developing disease. The apparent mechanism of ranibizumab action involved derepressing PDGFs, which, at the concentrations present in PVR vitreous, inhibited non-PDGF-mediated activation of PDGF receptor α. These preclinical findings suggest that available approaches to neutralize VEGF-A are prophylactic for PVR, and that anti-VEGF-based therapies may be effective for managing more than angiogenesis- and edema-driven pathological conditions.
Poole Perry LJ, Jakobiec FA, Zakka FR, Reichel E, Herwig MC, Perry A, Brat DJ, Grossniklaus HE. Reactive retinal astrocytic tumors (so-called vasoproliferative tumors): histopathologic, immunohistochemical, and genetic studies of four cases. Am J Ophthalmol 2013;155(3):593-608.e1.Abstract
PURPOSE: To evaluate the cellular nature of and diagnostic terminology used in connection with acquired retinal "vasoproliferative tumors." DESIGN: Retrospective clinicopathologic study. METHODS: Clinical records and microscopic slides of 4 enucleated globes were reviewed. Special stains and immunohistochemical probes for CD31, CD34, p53, glial fibrillary acidic protein (GFAP), CD163, and Ki67 (cell replication) were employed; ultrastructural and fluorescence in situ hybridization (FISH) analyses were performed. RESULTS: Tumors were located inferotemporally in middle-aged patients. They were uniformly composed of compacted elongated, GFAP-positive spindle cells (due to intermediate filaments identified ultrastructurally) with a Ki67 index of less than 1%. Rosenthal fibers and eosinophilic granular bodies were observed. Hyalinized periodic acid-Schiff-positive vessels were widely separated. CD31 and CD34 revealed a sparse microvasculature. Tumor-associated exudate spread predominantly subretinally. The retinal pigment epithelium had undergone extensive placoid fibrous metaplasia with focal ossification. P53 upregulation, BRAF-KIAA gene rearrangement, and IDH1R132H mutation typically associated with low-grade astrocytic neoplasms were absent. CONCLUSIONS: Retinal "vasoproliferative" tumors have been mischaracterized, because they actually display a paucity of microvessels. Proliferating fibrous astrocytes with a very low proliferation index predominate, without immunohistochemical or genetic evidence favoring a neoplasm. Subretinal exudate appeared capable of provoking widespread fibrous metaplasia of the pigment epithelium that was mainly responsible for secondary retinal damage. The term "reactive retinal astrocytic tumor" is proposed as more appropriate for this entity. In carefully selected progressive lesions, consideration should be given to earlier surgical intervention before extensive subretinal exudate accumulates and pigment epithelial proliferation with fibrous metaplasia ensues.
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Qazi Y, Hamrah P. Corneal Allograft Rejection: Immunopathogenesis to Therapeutics. J Clin Cell Immunol 2013;2013(Suppl 9)Abstract
Corneal transplantation is among the most successful solid organ transplants. However, despite low rejection rates of grafts in the 'low-risk' setting, rejection can be as high as 70% when grafted into 'high-risk' recipient beds. Under normal homeostatic conditions, the avascular cornea provides a unique environment that facilitates immune and angiogenic privilege. An imbalance in pro-inflammatory, angiogenic and lymphangiogenic mediators leads to a breakdown in corneal immune privilege with a consequent host response against the donor graft. Recent developments in lamellar and endothelial keratoplasties have reduced the rates of graft rejection even more, while providing improved visual outcomes. The corneal layer against which an immune response is initiated, largely determines reversibility of the acute episode. While epithelial and stromal graft rejection may be treated with topical corticosteroids with higher success, acute endothelial rejection mandates a more aggressive approach to therapy due to the lack of regenerative capacity of this layer. However, current immunosuppressive regimens come with the caveat of ocular and systemic side effects, making prolonged aggressive treatment undesirable. With the advent of biologics, efficacious therapies with a superior side effect profile are on the horizon. In our review we discuss the mediators of ocular immune privilege, the roles of cellular and molecular immune players in graft rejection, with a focus on human leukocyte antigen and antigen presenting cells. Furthermore, we discuss the clinical risk factors for graft rejection and compare rates of rejection in lamellar and endothelial keratoplasties to traditional penetrating keratoplasty. Lastly, we present the current and upcoming measures of therapeutic strategies to manage and treat graft rejection, including an overview of biologics and small molecule therapy.
Qazi Y, Hamrah P. Gene therapy in corneal transplantation. Semin Ophthalmol 2013;28(5-6):287-300.Abstract
Corneal transplantation is the most commonly performed organ transplantation. Immune privilege of the cornea is widely recognized, partly because of the relatively favorable outcome of corneal grafts. The first-time recipient of corneal allografts in an avascular, low-risk setting can expect a 90% success rate without systemic immunosuppressive agents and histocompatibility matching. However, immunologic rejection remains the major cause of graft failure, particularly in patients with a high risk for rejection. Corticosteroids remain the first-line therapy for the prevention and treatment of immune rejection. However, current pharmacological measures are limited in their side-effect profiles, repeated application, lack of targeted response, and short duration of action. Experimental ocular gene therapy may thus present new horizons in immunomodulation. From efficient viral vectors to sustainable alternative splicing, we discuss the progress of gene therapy in promoting graft survival and postulate further avenues for gene-mediated prevention of allogeneic graft rejection.
Qu J, Jakobs TC. The Time Course of Gene Expression during Reactive Gliosis in the Optic Nerve. PLoS One 2013;8(6):e67094.Abstract
Reactive gliosis is a complex process that involves changes in gene expression and morphological remodeling. The mouse optic nerve, where astrocytes, microglia and oligodendrocytes interact with retinal ganglion cell axons and each other, is a particularly suitable model for studying the molecular mechanisms of reactive gliosis. We triggered gliosis at the mouse optic nerve head by retro orbital nerve crush. We followed the expression profiles of 14,000 genes from 1 day to 3 months, as the optic nerve formed a glial scar. The transcriptome showed profound changes. These were greatest shortly after injury; the numbers of differentially regulated genes then dropped, returning nearly to resting levels by 3 months. Different genes were modulated with very different time courses, and functionally distinct groups of genes responded in partially overlapping waves. These correspond roughly to two quick waves of inflammation and cell proliferation, a slow wave of tissue remodeling and debris removal, and a final stationary phase that primarily reflects permanent structural changes in the axons. Responses from astrocytes, microglia and oligodendrocytes were distinctively different, both molecularly and morphologically. Comparisons to other models of brain injury and to glaucoma indicated that the glial responses depended on both the tissue and the injury. Attempts to modulate glial function after axonal injuries should consider different mechanistic targets at different times following the insult.
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Raghuram A, Hansen RM, Moskowitz A, Fulton AB. Photoreceptor and postreceptor responses in congenital stationary night blindness. Invest Ophthalmol Vis Sci 2013;54(7):4648-58.Abstract
PURPOSE: To investigate photoreceptor and postreceptor retinal function in patients with congenital stationary night blindness (CSNB). METHODS: Forty-one patients with CSNB (ages 0.19-32 years) were studied. ERG responses to a series of full-field stimuli were obtained under scotopic and photopic conditions and were used to categorize the CSNB patients as complete (cCSNB) or incomplete (iCSNB). Rod and cone photoreceptor (R(ROD), S(ROD), R(CONE), S(CONE)) and rod-driven postreceptor (V(MAX), log σ) response parameters were calculated from the a- and b-waves. Cone-driven responses to 30 Hz flicker and ON and OFF responses to a long duration (150 ms) flash were also obtained. Dark-adapted thresholds were measured. Analysis of variance was used to compare data from patients with cCSNB, patients with iCSNB, and controls. RESULTS: We found significant reduction in saturated photoreceptor amplitude (R(ROD), R(CONE)) but normal photoreceptor sensitivity (S(ROD), S(CONE)) in both CSNB groups. Rod-driven postreceptor response amplitude (V(MAX)) and sensitivity (log σ) were significantly reduced in CSNB. Log σ was significantly worse in cCSNB than in iCSNB; this was the only scotopic parameter that differed between the two CSNB groups. Photopic b-wave amplitude increased monotonically with stimulus strength in CSNB patients rather than showing a normal photopic hill. The amplitude of the 30-Hz flicker response was reduced compared with controls, more so in iCSNB than in cCSNB. The mean dark-adapted threshold was significantly elevated in CSNB, more so in cCSNB than in iCSNB. CONCLUSIONS: These results are evidence of normal photoreceptor function (despite the low saturated photoresponse amplitude) and anomalous postreceptor retinal circuitry.
Rahimi Darabad R, Suzuki T, Richards SM, Jensen RV, Jakobiec FA, Zakka FR, Liu S, Sullivan DA. Influence of aromatase absence on the gene expression and histology of the mouse meibomian gland. Invest Ophthalmol Vis Sci 2013;54(2):987-98.Abstract
PURPOSE: We hypothesize that aromatase, an enzyme that controls estrogen biosynthesis, plays a major role in the sex-related differences of the meibomian gland. To begin to test this hypothesis, we examined the influence of aromatase absence, which completely eliminates estrogen production, on glandular gene expression and histology in male and female mice. METHODS: Meibomian glands were obtained from adult, age-matched wild-type (WT) and aromatase knockout (ArKO) mice. Tissues were processed for histology or the isolation of total RNA, which was analyzed for differentially expressed mRNAs by using microarrays. RESULTS: Our results show that aromatase significantly influences the expression of more than a thousand genes in the meibomian gland. The nature of this effect is primarily sex-dependent. In addition, the influence of aromatase on sex-related differences in gene expression is predominantly genotype-specific. However, many of the sex-related variations in biological process, molecular function, and cellular component ontologies, as well as in KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, are remarkably similar between WT and ArKO mice. The loss of aromatase activity has no obvious effect on the histology of meibomian glands in male or female mice. CONCLUSIONS: Our findings demonstrate that aromatase has a significant impact on gene expression in the meibomian gland. The nature of this influence is sex-dependent and genotype-specific; however, many of the sex-related variations in gene ontologies and KEGG pathways are similar between WT and ArKO mice. Consequently, it appears that aromatase, and by extension estrogen, do not play a major role in the sex-related differences of the mouse meibomian gland.
Rizzo JF. Festschrift for Simmons Lessell, MD. J Neuroophthalmol 2013;33(4):e26-7.

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