Moorfields Eye Hospital

About: Moorfields Eye Hospital is a healthcare organization based out in London, United Kingdom. It is known for research contribution in the topics: Visual acuity & Glaucoma. The organization has 3721 authors who have published 6790 publications receiving 246004 citations.

Autologous serum eyedrops for dry eyes and epithelial defects: clinical and in vitro toxicity studies

Abstract: BACKGROUND/AIMS Autologous serum drops have been reported to be beneficial in keratoconjunctivitis sicca (KCS) and persistent epithelial defects (PED). A clinical pilot study was carried out to examine these potential uses and in vitro toxicity testing on corneal epithelial cell cultures was performed to compare the effect of serum drops with unpreserved hypromellose (hydroxypropylmethylcellulose 0.3%). METHODS Patients with KCS and PED, unresponsive to conventional treatment were recruited. Patients were examined before treatment, at 1 and 2 weeks after initiation, and then 2 weekly until treatment ceased. Symptoms were assessed at each visit. Clinical examination included Schirmer's test without anaesthesia, rose bengal staining, and fluorescein staining. Epithelial defects were measured with the slit beam. In the laboratory, cultured human corneal epithelial cells were exposed to serum drops and hypromellose, and their viability evaluated with fluorescent viability staining (Calcein AM ethidium homodimer) and an ATP assay. RESULTS Autologous serum was used in 15 eyes of 13 patients with PED and 11 eyes of nine patients with KCS. In two patients serum drops were started after penetrating keratoplasty (PK). The PKs were performed for perforations secondary to PEDs. Of the 15 eyes with PED, nine healed at a mean of 29 days and six failed. The mean duration of PED before the use of serum drops was 48.2 days. Of the 11 eyes with KCS, six had improved subjective scores and fluorescein scores, and five had improved rose bengal scores after the use of serum drops. For the two patients who used serum eyedrops post-PK, there was a stable and intact epithelium at 1 week. Cessation of serum drops during the postoperative period led to deterioration in the subjective and objective scores in both patients. One developed a PED that responded to reinstitution of serum drops. The morphology and ATP levels of cultured epithelial cells exposed to serum were better maintained than those exposed to hypromellose. CONCLUSION Autologous serum drops are useful for PED and KCS. This effect may be related to a number of active factors in serum including growth factors, fibronectin, vitamin A, and anti-proteases. In vitro toxicity testing demonstrated that serum drops have reduced toxicity compared with unpreserved hypromellose. Currently regulatory restrictions in the UK have prevented the establishment of a prospective randomised controlled trial examining the efficacy of autologous serum drops for the management of this group of ocular surface disorders.

A new local anesthesia technique for cataract extraction by one quadrant sub-Tenon's infiltration.

Abstract: A new technique of local anesthetic administration has been used for 50 patients undergoing cataract extraction. The simple technique involves direct transconjunctival infiltration of local anaesthetic directly to the sub-Tenon's space, in the inferior-nasal quadrant, using a blunt 19-gauge Southampton cannula. This method seeks to avoid the risks of retrobulbar haemorrhage, perforation of the globe, damage to the optic nerve, and injection into the subarachnoid space, whilst providing prolonged and reliable anaesthesia. Akinesia is achieved by the inferior-nasal placement of solution and if not sufficient, a top-up can easily be given. Patients graded any discomfort or pain using a 10 cm visual analogue graphical pain score chart with numerical and descriptive rating scale. The delivery of 50:50 mixture of lignocaine 2% and bupivacaine 0.5% anaesthetic was evaluated by patients with a median response of 'slight discomfort'. The operative procedure was graded with a median of 'no pain or discomfort', both for extracapsular cataract extraction and phakoemulsification. This is a new, modified, sub-Tenon technique which is simple, reliable, and which offers excellent anaesthesia and akinesia and avoids a sharp instrument being passed into the orbit.

In vitro characterization of a spontaneously immortalized human Müller cell line (MIO-M1).

Abstract: Purpose: To characterize a spontaneously immortalized human Muller cell line and to determine whether it retains the characteristics of primary isolated cells without undergoing differentiation in vitro. Methods: An immortalized cell line obtained from human retina was investigated for the expression of known markers of Muller cells, including cellular retinaldehyde binding protein (CRALBP), glutamine synthetase, epidermal growth factor receptor (EGF-R), -smooth muscle actin (-SMA), and glial fibrillary acidic protein (GFAP). Also examined were the morphologic features of these cells, by scanning and transmission electron microscopy, and their functional characteristics, by electrogenic responses to glutamate. In addition, comparative studies were made of these cells with primary cultures of freshly isolated human Muller cells. Results: The cells expressed CRALBP, EGF-R, glutamine synthetase, and -SMA, as judged by confocal microscopy and Western blot analysis of cell lysates. Western blot analysis did not detect GFAP in cell lysates, but confocal microscopy showed that occasional cells expressed GFAP after detachment from the monolayer. The morphologic features of the cells examined, as judged by scanning and transmission electron microscopy, resemble those of cells derived from primary cell cultures. They possess villous projections on their apical surfaces and contain loose bundles of microtubules aligned parallel to one another and the long axis of the cell process. Characteristically, they contain abundant deposits of glycogen particles that do not differ from those seen in primary isolated cells. Preliminary recordings with intracellular electrodes revealed that these cells have properties similar to those described for mammalian Muller cells and depolarize in response to L-glutamate without significant change in membrane resistance, consistent with the well-established electrogenic uptake of this amino acid. Conclusions: A spontaneously immortalized Muller cell line was characterized that retains the characteristics of primary isolated cells in culture. To the authors’ knowledge, it constitutes the first human Muller cell line reported in the literature. It has been named MIO-M1 (Moorfields/Institute of Ophthalmology-Muller 1) after the authors’ institution. Availability of this human cell line will facilitate studies designed to obtain a better understanding of the role of Muller cells in normal and pathologic conditions.