Optical Coherence Tomographic Finding in a Case of Macular Coloboma

PURPOSE: To report the optical coherence tomography (OCT) findings in a patient with unilateral macular coloboma. METHODS: A 12-year-old male was presented with macular coloboma in the left eye. The optical coherence tomography was performed with fluorescein angiography (FA). RESULTS: The OCT revealed the crater-like depression in the macula, demonstrating atrophic neurosensory retina, and an absence of retinal pigment epithelium and choroid in the lesion. FA showed hypofluorescence corresponding to the size of the lesion in both early and late frames without leakage of dye at any stage. CONCLUSIONS: The OCT can be beneficial to confirm the diagnosis of macular coloboma

Berger’s space

Introduction and Objective: The Berger’s space (BS) is a space located between the posterior capsule of the lens and the anterior hyaloid of the vitreous, structures that adhere in a circular manner by means of the Wieger ligament, for which the outer limit is defined by Egger´s line. The aim of this article is to perform a review of the BS, as well as to present three cases in which this BS could be demonstrated by optical coherence tomography (OCT). Material and Method: A total of 90 patients from a general ophthalmology clinic were studied, on whom an anterior pole OCT was performed (Cirrus Lumera 700 Carl Zeiss Medicte, Dublin, California, United States). All patients were included consecutively, with an analysis being performed on the cornea, anterior chamber, iris, lens, and anterior vitreous, but excluding those in which the test could not be performed. Results: The posterior lens capsule, the anterior hyaloid, and the BS between both structures were observed in three patients. This is the first time in the current literature that three cases have been described, together with their characteristics (one phakic –case 1- and two pseudophakic, one of them vitreous destructuring –case 2- and the other with opacification of the posterior capsule of the lens –case 3-), using this previous pole OCT technique. Conclusions: Knowledge of the BS is essential to understand the vitreo-lenticular junction and any complications in some cataract surgeries, as well as to also understand the pathological origin of pigment dispersion syndrome

Increased SK3 expression in DM1 lens cells leads to impaired growth through a greater calcium-induced fragility

Although cataract is a characteristic feature of myotonic dystrophy type 1 (DM1), little is known of the underlying mechanisms. We generated four lens epithelial cell lines derived from DM1 cataracts and two from age-matched, non-DM cataracts. Small-pool PCR revealed typical large triplet repeat expansions in the DM1 cells. Furthermore, real-time PCR analysis showed reduced SIX5 expression and increased expression of the Ca2+-activated K+ channel SK3 in the DM1 cells. These cells also exhibited longer population doubling times which did not arise through reduced proliferation, but rather increased cell death as shown by increased release of lactate dehydrogenase (LDH). Using 86Rb+ as a tracer for K+, we found no difference in the resting K+ influx or efflux kinetics. In all cases, the ouabain sensitive component of the influx contributed ~50% of the total. However, stimulating internal Ca2+ by exposure to ionomycin not only caused greater stimulation of K+ (86Rb) efflux in the DM1 cells but also induced a higher rate of cell death (LDH assay). Since both the hyper-stimulation of K+ efflux and cell death were reduced by the highly specific SK inhibitor apamin, we suggest that increased expression of SK3 has a critical role in the increased Ca2+-induced fragility in DM1 cells. The present data, therefore, both help explain the lower epithelial cell density previously observed in DM1 cataracts and provide general insights into mechanisms underlying the fragility of other DM1-affected tissues

The length-tension diagrams of human oblique muscles in trochlear palsy and strabismus sursoadductorius

We determined the relation between length and tension in detached oblique muscles of 16 strabismus patients that underwent surgery, before and during contraction evoked by intravenous administration of succinylcholine. We frequently found a nonlinear relation between length and tension, unlike our previous findings in recti. In superior oblique palsies, the superior oblique was found, before injection of succinylcholine, to be stiff after elongation, and did not contract after injection of succinylcholine, while the ipsilateral inferior oblique contract after injection of succinylcholine, but with a higher spring constant than did usual. In 3 cases the superior oblique contracted vividly after administration of succinylcholine despite the presence of excyclotropia, stereopsis, torticollis (2 cases) and a hypertropia that increased in adduction, in downgaze, in adduction-and-downgaze and on ipsilateral head-tilt. The finding of a vividly contracting superior oblique is incompatible with the diagnosis of a complete superior oblique palsy. We conclude that some of the cases diagnosed as congenital superior oblique palsy, having a hypertropia increasing in adduction, in downgaze, in adduction-and-downgaze and on ipsilateral head-tilt, are in fact cases of unilateral strabismus sursoadductorius (upshoot in adduction), a non-paretic motility disorder

Seborrheic Keratosis of the Conjunctiva: A Case Report

Seborrheic keratosis is a benign epithelial neoplasia that occurs mainly in the skin of the eyelids and face. We describe a case of seborrheic keratosis of the conjunctiva confirmed by histopathology. A 72-year-old man presented with a recurrent conjunctival mass involving the nasal side of his right eye. Clinically, a diagnosis of conjunctival papilloma was made, and a mass excision was performed. The histopathological analysis evidenced a conjunctival-covering epithelium with papillomatous changes and irregular acanthosis, at the expense of a proliferation of basaloid cells. In addition, the lesion exhibited multiple pseudohorn cysts containing keratin. With the above findings, a diagnosis of conjunctival seborrheic keratosis was established. The occurrence of seborrheic keratosis on the conjunctiva is rare. In this case, seborrheic keratosis was confirmed by pathologic report despite its similar appearance with papilloma. Seborrheic keratosis should be considered in the differential diagnosis of conjunctival lesions

The effect of varying glucose levels on the ex vivo crystalline lens: implications for hyperglycaemia-induced refractive changes

Purpose: Refractive changes in diabetic eyes have long been reported but with equivocal results. The lens has been a more recent focus as the source of any change but it is possible that multiple sources of variation have made it difficult to demonstrate a systematic change clinically. The aim of this study was therefore to use a bovine lens model to investigate the optical changes in hyperglycaemia and when lenses are returned to normal glucose levels as would occur following commencement of treatment. Method: Bovine eyes were obtained and their lenses excised under sterile conditions before placing them in culture medium within an incubator using standard tissue culture techniques. In the first experiment, lenses were transferred into culture medium containing 5 mm (n = 12), 15 mm (n = 12) and 30 mm (n = 12) glucose. Measurements were made of the change in back vertex focusing distance with equatorial lens diameter using the ScanTox™ measurement system. From these measurements, the back vertex focal length and primary longitudinal spherical aberration were derived. In a second experiment, lenses maintained at 30 mm glucose (n = 7) were stepped down to 5 mm glucose to simulate starting diabetic therapy and measured in the same way. Changes over time were assessed with a linear regression model. Results: A trend towards myopia was observed with increasing hyperglycaemia, this was not statistically significant. When lenses were stepped-down from hyperglycaemia to normal physiological levels of glucose, a hyperopic shift was observed in line with published clinical studies that again failed to reach statistical significance. High variability in the measurement on longitudinal spherical aberration prevented any significant trends being measured. Conclusions: Our results suggest that there are no consistent crystalline lens-induced refractive changes following exposure to hyperglycaemia for time-periods up to 5 days used in the current study. It is possible that bovine lenses are able to offset the raised osmotic pressure from high glucose levels in the short-term by a process of osmoregulation and that repeated osmotic stress or longer term exposure may be required to induce the changes in refraction that are seen clinically