Reconciling visual field defects and retinal nerve fibre layer asymmetric patterns in retrograde degeneration: an extended case series.

BACKGROUND: Accurate diagnosis in patients presenting with lesions at various locations within the visual pathway is challenging. This study investigated functional and structural changes secondary to such lesions to identify patterns useful to guide early and effective management. METHODS: Over 10,000 records from patients referred for optic nerve head assessment were reviewed and 31 patients with a final diagnosis of likely neuropathic lesions posterior to the eye were included in the current study. Fundus photographs, optic coherence tomography images and visual field tests were evaluated for changes with respect to retinal nerve fibre layer topography and prediction of structure-function paradigms. Emerging clinical patterns were examined for their consistency with the likely anatomical origin of the underlying insult in the presence of varying diagnoses. RESULTS: Data from patients with lesions along the visual system allowed identification of retinal nerve fibre layer asymmetry correlated with visual field defects and ganglion cell analysis. Bilateral discordance in retinal nerve fibre loss easily discernible from an altered pattern of the temporal-superior-nasal-inferior-temporal curve was characteristic for post-chiasmal lesions. These sometimes-subtle changes supported diagnosis in cases with multiple aetiologies or with ambiguous visual field analysis and/or ganglion cell loss. CONCLUSION: Intricate knowledge of the retinal architecture and projections allows coherent predictions of functional and structural deficits following various lesions affecting the visual pathway. The integration of adjunct imaging and retinal nerve fibre layer thinning will assist clinicians to guide clinical investigations toward a likely diagnosis in the light of significant individual variations. The case series presented in this study aids in differential diagnosis of retrograde optic neuropathies by using retinal nerve fibre layer asymmetric patterns as an important clinical marker.

OCT and Fundus Autofluorescence Enhances Visualization of White Dot Syndromes.

PURPOSE: White dot syndromes (WDS) are a group of inflammatory conditions characterized by white lesions at the retina and choroid level. Detection and monitoring of these syndromes are currently hampered by the subtlety of these lesions, making them difficult to image using traditional clinical techniques. New imaging modalities such as optical coherence tomography (OCT) and fundus autofluorescence (FAF) offer new opportunities for clinicians to noninvasively image WDS. METHODS: A literature search was performed using a variety of WDS as the search terms. All articles from January 2004 to May 2014 were analyzed for clinical information regarding imaging of the diseases using OCT or FAF. RESULTS: Current descriptions of OCT and FAF imaging of WDS are fragmented across case reports and small-scale studies. Assessing clinical presentation of WDS using OCT and FAF, however, is useful as the retinal layers affected in these syndromes are well characterized by these technologies. Furthermore, the new information revealed by OCT and FAF is helpful to elucidate the underlying mechanisms of these diseases in combination with known clinical and angiographic findings. CONCLUSIONS: This review collates current literature and provides a succinct overview of the clinical presentation of WDS using OCT and FAF.

Use of adjuvant hyperbaric oxygen therapy to support limbal conjunctival graft in the management of recurrent pterygium.

PURPOSE: To assess the role of hyperbaric oxygen therapy (HBOT) in the management of recurrent pterygium. METHODS: Thirty-nine eyes with recurrent pterygium were treated with surgical excision and limbal conjunctival autograft, followed by a course of HBOT. Patients were followed for development of recurrence. RESULTS: Of the 39 eyes, 18 had a known history of exposure to beta radiation or mitomycin C. The mean duration of follow-up in this group was 23.1 months. A single recurrence was noted in this group. For the remaining 21 eyes, the mean duration of follow-up was 19.4 months. No recurrences were recorded in this group. No significant complications from HBOT were recorded. CONCLUSIONS: The use of HBOT together with excision and limbal conjunctival autograft for recurrent pterygium is associated with a low recurrence rate. Adjuvant HBOT should be considered in the surgical management of recurrent pterygium.

Crystal structure of the soluble form of the redox-regulated chloride ion channel protein CLIC4.

The structure of CLIC4, a member of the CLIC family of putative intracellular chloride ion channel proteins, has been determined at 1.8 Angstroms resolution by X-ray crystallography. The protein is monomeric and it is structurally similar to CLIC1, belonging to the GST fold class. Differences between the structures of CLIC1 and CLIC4 are localized to helix 2 in the glutaredoxin-like N-terminal domain, which has previously been shown to undergo a dramatic structural change in CLIC1 upon oxidation. The structural differences in this region correlate with the sequence differences, where the CLIC1 sequence appears to be atypical of the family. Purified, recombinant, wild-type CLIC4 is shown to bind to artificial lipid bilayers, induce a chloride efflux current when associated with artificial liposomes and produce an ion channel in artificial bilayers with a conductance of 30 pS. Membrane binding is enhanced by oxidation of CLIC4 while no channels were observed via tip-dip electrophysiology in the presence of a reducing agent. Thus, recombinant CLIC4 appears to be able to form a redox-regulated ion channel in the absence of any partner proteins.

Centripetal lens epithelial cell migration: a prospective study of the Alcon SA60AT intraocular lens.

PURPOSE: To evaluate prospectively the incidence and severity of centripetal lens epithelial cell migration (CLECM) onto the anterior surface of the Alcon SA60AT intraocular lens (IOL). METHODS: One hundred and four consecutive cases of SA60AT IOL implantations were prospectively evaluated. At the 1-month postoperative visit, best corrected visual acuity (BCVA) was obtained. Following maximal pupillary dilatation, the extent of CLECM was assessed using a simplified grading scale (0-4). The centrality of the lens within the capsular bag was recorded. Patients with the highest grade of CLECM were recalled for reassessment at a minimum of 3 months. RESULTS: Centripetal lens epithelial cell migration data were obtained on 99 patients. Of these, 94% demonstrated CLECM of varying severity at 1 month postoperatively. The severity was low grade in 54% of patients (29% grade 1, 24% grade 2), and high grade in 40% of patients (16% grade 3, 24% grade 4). BCVA results were good (91.9% 6/6 or better) and did not correlate with CLECM grade. Operative capsulorhexis size did not correlate with the severity of CLECM. The lens was well-centred in 91 of 92 patients in whom lens position was assessed. Twenty-three patients with grade 4 CLECM at 1 month were brought back for reassessment (3.5-13 months postoperatively) and 18 of these demonstrated complete regression of CLECM (to grade 0). CONCLUSIONS: There is a high incidence and severity of CLECM 1 month postoperatively using the Alcon SA60AT IOL. There was no significant correlation between CLECM grade and either BCVA at 1 month, capsulorhexis size or lens centration. CLECM appears to be a frequent, benign and transient event with this lens.

Acute haptic-induced pigmentary glaucoma with an AcrySof intraocular lens.

A 49-year-old man had uneventful endocapsular phacoemulsification with in-the-bag implantation of an AcrySof SA60AT single-piece intraocular lens (IOL) (Alcon) in the right eye. Twenty-seven days postoperatively, he presented with ocular pain, intraocular pressure of 48 mm Hg, 360 degrees of hyperpigmentation of the trabecular meshwork, and iris pigment epithelial atrophy in the region of the upper temporal haptic, which had dislocated into the sulcus. The patient made an excellent recovery following IOL removal and exchange. Scanning electron microscopy of the explanted IOL demonstrated that the haptic had a rough lateral surface and anterolateral edge. We do not think this IOL should be implanted in the sulcus placement of the heptics. In this article, we report the case of a patient with an AcrySof SA60ATIOL (Alcon) who developed acute pigmentary glaucoma when the inferior haptic slipped out of the bag and came into contact with the pigmented iris and ciliary body.