PURPOSE: To assess depth of field in phakic and pseudophakic eyes to explain good distance and uncorrected near visual acuity in pseudophakic eyes. SETTING: Department of Ophthalmology, University of Otago Medical School, Dunedin, New Zealand. METHODS: Depth of field was measured in pseudophakic (n = 10) and phakic (n = 10) eyes for both near and distant targets. Test conditions included cycloplegia and a constant pupillary aperture using a soft contact lens with a central artificial pupil diameter of 2.5 mm. RESULTS: There was no statistically significant difference between phakic and pseudophakic eyes for any test. Depth of field for near visual acuity was +/-0.85 diopters (D), but amplitude of legibility was +/-1.94 D. Depth of field for distance visual acuity was between 0.25 and 0.50 D in 85% of eyes. CONCLUSION: In the absence of astigmatism and disease, a pseudophakic eye with -0.75 D of myopia can expect to achieve 20/30 uncorrected distance acuity and read N5 unaided if the pupil is approximately 2.5 mm.

Accommodation, Ocular↗

PubMed1996

Anterior lamellar repositioning and grey line split for upper lid entropion in ocular cicatricial pemphigoid.

PURPOSE: Trichiasis in ocular cicatricial pemphigoid (OCP) is usually due to cicatricial entropion and is a major cause of ocular morbidity. Unfortunately in this disease, direct surgery on the conjunctiva often results in marked inflammation and cicatrisation. This paper assessed a procedure that corrects cicatricial entropion of the upper lid while avoiding surgery to the conjunctiva. METHODS: A grey line upper lid split and a vertical anterior lamellar repositioning was performed on 16 lids of 11 patients with OCP. RESULTS: Anatomical success was achieved in 72% of lids at 1 year and 61% had complete success with no lashes touching the globe. These outcomes were maintained up to 4 years. There were no perioperative complications. Two patients post-operatively developed severe conjunctival inflammation that required systemic immunosuppression. The causes of failure were primary surgical failure (n = 2), progression of cicatrisation secondary to surgically induced inflammation (n = 1), development of misdirected lashes (n = 1) and late recurrence at 7 months (n = 1). One patient developed peaking of the eyelid. CONCLUSIONS: This procedure has a good long-term outcome with minimal complications. Activation of severe conjunctival inflammation occurred in 13% of cases and this must be considered pre- and post-operatively.

Aged↗

PubMed1996

Biofilm formation in infectious crystalline keratopathy due to Candida albicans.

Infectious crystalline keratopathy (ICK) is an uncommon, indolent corneal infection in which the slow clinical course contrasts with the rapid laboratory growth and microbiological sensitivities of the infecting organism. This prospective study aimed to determine whether biofilm production was the cause of this disparity. A case of failed medical management of ICK in a patient with Stevens-Johnson syndrome is presented. A penetrating keratoplasty yielded corneal tissue that was freshly fixed for electron microscopy using 0.05% ruthenium red and 2.5% gluteraldehyde. Candida albicans was grown from 3/3 broths, and fungi with morphology consistent with Candida were seen on histological examination. Electron microscopy revealed microorganisms morphologically typical of Candida surrounded by a polysaccharide-rich glycocalyx consistent with a biofilm. We concluded that Candida albicans is capable of producing a biofilm and is a known cause of ICK. This case is supportive evidence that biofilm production is associated with cases of ICK and may explain the chronic, pauciinflammatory features of ICK and its relative resistance to antibiotic treatment.

Biofilms↗

PubMed1996

Progression of disease in ocular cicatricial pemphigoid.

BACKGROUND: Ocular cicatricial pemphigoid (OCP) is a sight threatening autoimmune disease that can lead to severe conjunctival cicatrisation and keratopathy. It has a variable course and little is known about the factors that determine disease progression. This study analysed the factors that have prognostic significance regarding disease outcome, progression, and keratopathy. METHODS: Sixty six patients with OCP were monitored prospectively at Moorfields Eye Hospital. The influence of ocular features, the systemic disease, and the management were analysed to identify factors that influence the outcomes and disease progression. RESULTS: The mean age at presentation was 67 years; 56% were men. The binocular visual acuities were 6/24 or worse in 25%. Extensive cicatrisation at presentation was common but correlated only weakly with the visual prognosis. Systemic manifestations included lesions of the mouth in 44%, pharynx in 30%, oesophagus in 27%, nose/sinus in 18%, and skin in 17%. There was no association between the ocular and systemic manifestations. Persistent corneal epithelial defects and limbitis occurred in 18% and 32%, respectively, and both were associated with a worse visual prognosis. Systemic immunosuppression was ultimately prescribed in 74%, mainly in patients with advanced stages of conjunctival cicatrisation. Of patients with more than 24 months follow up, progression of cicatrisation occurred in 35% of eyes (16/46) all but one of which were associated with episodes of conjunctival inflammation. CONCLUSIONS: Persistent epithelial defects, limbal inflammation, and ongoing conjunctival inflammation are important factors that lead to keratopathy and visual handicap. These require aggressive management, often with systemic immunosuppressive treatment. Close follow up is required in cases with extensive cicatrisation.

Adult↗

PubMed1996

Sulphapyridine--a new agent for the treatment of ocular cicatricial pemphigoid.

AIMS: Ocular cicatricial pemphigoid (OCP) is a severe, potentially sight threatening systemic disease that sometimes requires systemic immunosuppression. This study assessed the clinical outcome of patients with OCP treated with sulphapyridine, a sulphonamide with an anti-inflammatory and immunosuppressive action but few side effects. METHODS: A prospective, single armed, unmasked clinical trial was undertaken at Moorfields Eye Hospital. Twenty consecutive patients with moderate or marked conjunctival inflammation due to OCP were treated with oral sulphapyridine 500 mg twice daily. The degree of ocular inflammation was assessed as nil, mild, moderate, marked, or severe. Success was defined as resolution to mild or less. Ocular limbitis, systemic features of the disease, and side effects of the drug were also monitored. RESULTS: Follow up was a mean of 12.3 (SD 4.0) months and ranged from 7 to 17 months. A successful reduction in inflammation was recorded in 22/39 eyes (56%) and 10/20 patients (50%). This improvement occurred within 1 month in 64% and in all by 2 months. Three patients developed allergy. Other side effects included nausea (n = 3), headache (n = 1), urinary hesitancy (n = 1), and mild lymphocytopenia (n = 1). These were dose dependent. Progression of cicatrisation was observed in 1/22 eyes. Success was less likely if there were systemic features of OCP or ocular limbitis. CONCLUSIONS: Sulphapyridine was clinically effective in 50% of patients with moderate marked inflammation and had few side effects. It is a good alternative to dapsone.

Administration, Oral↗

PubMed1996

The true rate of success in argon laser eyelash thermoablation.

Argon laser thermoablation has a success rate of 50% typically, when success is defined as an absence of recurrence of any eyelash per lid treated. When success is redefined as an absence of recurrence per eyelash treated, the success rate increases to 76% to 93%. Laser thermoablation potentially offers selective eyelash ablation with minimal inflammation and adjacent tissue damage. Its true rate of success may be better than previously indicated.

Eyelashes↗

PubMed1995

Chemotherapy for acanthamoeba keratitis.

Explore the source record for details and available documents.

Acanthamoeba Keratitis↗

PubMed1995

Biofilm-related infections in ophthalmology.

A biofilm is a functional consortium of microorganisms organised within an extensive exopolymer matrix. Organisms within a biofilm are difficult to eradicate by conventional antimicrobial therapy and can cause indolent infections. This paper reviews the pathophysiology of biofilms and their application of ophthalmology. Under certain environmental conditions such as nutrient limitation, some bacteria may secrete and reside in an exopolysaccharide glycocalyx polymer. This confers relative protection from humoral and cellular immunity, antibiotics and surfactants. Biofilms occur in natural aquatic ecosystems, on ship hulls, in pipelines and on the surface of biomaterials. They cause clinical infections of prosthetic hip joints, heart valves and catheters. Biofilm formation may occur rapidly on contact lenses and their cases and hence contribute to the pathogenesis of keratitis. Formation of biofilms is also implicated in delayed post-operative endophthalmitis and crystalline keratopathy. Bacteria within biofilms are 20-1000 times less sensitive to antibiotic than free-living planktonic organisms. Existing experimental methods for modifying biofilm include the use of macrolide antibiotics that specifically impair biofilm production, and the use of enzymes to digest it. These may have clinical applications, as potential adjunctive therapies to antibiotic treatment, for these resistant infections. In conclusion, biofilm is an important cause of infections associated with biomaterials. Novel strategies are needed to deal with these.

Biofilms↗

PubMed1995

Inferior retractor plication surgery for lower lid entropion with trichiasis in ocular cicatricial pemphigoid.

AIMS: To assess the outcome of inferior retractor plication surgery for lower lid entropion in patients with ocular cicatricial pemphigoid (OCP). This technique avoids surgery on the conjunctiva that can result in exacerbations of disease activity. METHODS: This prospective study assessed the outcomes of a standard 'Jones' type plication in 14 lids of 10 patients with OCP. Seven patients were taking systemic immunosuppression and no patients had conjunctival inflammation for the 4 months before surgery. RESULTS: Life table analysis showed a 77% chance of anatomical success at 2 years and a 54% chance of completely preventing lash-globe touch. The surgery did not cause clinical activation of conjunctival inflammation or other complications. Anatomical failure was primary (n = 2) and due to late cicatrisation (n = 1). Three further cases had restoration of normal anatomy but the patients had persistently misdirected lashes that touched the globe. CONCLUSION: This technique gives good anatomical success over long periods and is particularly safe when there is no conjunctival inflammation present before surgery.

Aged↗