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J F Talbot

Publications and source records attributed to J F Talbot.

At least 19 recordsLinked to original sources
PubMed2002

A prospective, case controlled study of the natural history of diabetic retinopathy and maculopathy after uncomplicated phacoemulsification cataract surgery in patients with type 2 diabetes.

AIM: To determine if uncomplicated phacoemulsification cataract surgery is associated with an accelerated rate of progression of diabetic retinopathy or maculopathy postoperatively. METHODS: A prospective trial of 50 type 2 diabetics undergoing monocular phacoemulsification cataract surgery by a single consultant surgeon. The grade of diabetic retinopathy and diabetic maculopathy in the operated and non-operated fellow eye was assessed preoperatively and for 12 months postoperatively. RESULTS: Overall, retinopathy progression was observed in 11 patients. In seven the retinopathy progressed in both eyes, in three it progressed in the operated eye alone, and in one it progressed in the fellow eye alone. Macular oedema was observed in 13 eyes postoperatively. Four had transient pseudophakic cystoid macular oedema and nine true diabetic maculopathy. Where maculopathy progressed it did so symmetrically in five patients, it progressed in the operated eye alone in four patients, and the fellow eye alone in two patients. There was no significant difference in the number of operated and fellow eyes whose retinopathy or maculopathy progressed postoperatively. In both the operated (OE) and non-operated (NoE) eyes retinopathy progression was associated with a higher mean HbA(1)C (OE p=0.003; NoE p=0.001) and insulin treatment (OE p=0.008, NoE p=0.04). CONCLUSION: Uncomplicated phacoemulsification cataract surgery does not cause acceleration of diabetic retinopathy postoperatively and any progression that is observed probably represents the natural history of the disease. Although macular oedema is common after cataract surgery it may follow a benign course and in many patients the development of clinically significant macular oedema postoperatively probably represents natural disease progression rather than being a direct effect of surgery.

Aged↗
PubMed2001

Pupillary distortion and staphyloma following trans-scleral contact diode laser cyclophotocoagulation: a clinicopathological study of three patients.

PURPOSE: To search for the cause of scleral thinning and pupillary distortion following trans-scleral contact diode laser cyclophotocoagulation (TCDLC). METHODS: We reviewed the records of 3 patients in whom there were complications of scleral thinning and pupillary distortion following TCDLC. One of the eyes was later enucleated, and we present the histopathological findings. Using the histopathological features in this patient, we discuss the possible pathogenesis of the scleral thinning and pupillary distortion. RESULTS: Case 1 is a 46-year-old white woman who following TCDLC in an area of clinically normal sclera developed a staphyloma. Case 2 is a 52-year-old white woman who following TCDLC in an area of scarred sclera developed mild thinning. Case 3 is an 85-year-old white man who following TCDLC developed pupillary distortion, and gonioscopy revealed damage to the peripheral iris. Histological examination of case 1 revealed the staphyloma covered by a thin layer of conjunctival epithelium, collagen and vitreous condensation. We also observed cicatricial cilary body contraction causing distortion of the pupil and lens. CONCLUSIONS: Therapeutic TCDLC can produce scarring of the iris root, anterior chamber angle, draining structures and ciliary body, and may result in pupillary distortion. Pre-existing scleral scars may predispose to scleral damage following TCDLC. We discuss a simple strategy to avoid this complication of TCDLC.

Aged↗
PubMed2001

A prospective evaluation of the Heidelberg retina flowmeter in diagnosing ischaemia following branch retinal vein occlusion: a masked, controlled comparison with fluorescein angiography.

PURPOSE: To evaluate the use of the Heidelberg retina flowmeter (HRF) in diagnosing retinal ischaemia following macular branch retinal vein occlusion. METHODS: Ten patients with ischaemic macular branch retinal vein occlusion, as determined by strict fluorescein angiographic criteria, were examined with the HRF. Blood flow, blood volume and blood velocity characteristics from areas of ischaemic and non-ischaemic retina were recorded and the results between the normal and ischaemic areas of retina compared with paired t-test analysis. Ten healthy volunteers were similarly examined and acted as a control group. RESULTS: Compared with normal retina the HRF recorded a statistically significant reduction in blood flow within the ischaemic retina in 7 of the 10 study patients. In 2 patients the HRF actually recorded a statistically significant increase in blood flow in the area of ischaemic retina; there was no significant difference in the blood flow recorded in the normal and ischaemic retina in the remaining patient. HRF examination of the control group revealed a significant difference in the blood flow between two areas of apparently normal retina in 3 of the 10 volunteers. CONCLUSION: The HRF is not a reliable tool for diagnosing retinal ischaemia following branch retinal vein occlusion. Our results may suggest that the HRF blood flow recordings are not derived from the retinal circulation alone, but represent the cumulative blood flow through the combined circulations of the retina and choriocapillaris.

Aged↗
PubMed2000

Retinal vascular changes associated with transpupillary thermotherapy for choroidal melanomas.

PURPOSE: To define retinal vascular changes after transpupillary thermotherapy (TTT) for choroidal melanomas and assess their clinical impact. METHODS: Stereoscopic fluorescein angiogram pairs of 29 patients pre- and post-treatment with TTT were examined for patterns of vascular damage, and the patients were studied for ensuing complications. RESULTS: Widespread retinal capillary loss was confined within the treatment margins except in cases of coexisting large retinal artery or vein occlusions. Artery occlusions occurred in 83%, involving a large artery in 23%. Venous occlusions occurred in 69%, involving large veins in 10%. Subretinal choroidal neovascularization occurred in four cases, in one causing hemorrhage that broke through into the vitreous. No retinal neovascularization occurred. Choroidal vasculature was relatively preserved at the periphery of the treated area. Foveal vascular damage caused visual loss in six cases. Vascular changes beyond the treatment margins did not affect the fovea in any case. Retinal fibrosis affected two cases. Diabetic patients fared no worse than healthy counterparts. CONCLUSIONS: Transpupillary thermotherapy produces characteristic retinal vascular changes that may reduce vision when affecting the fovea. Vascular changes are confined within the treatment margins except in cases of associated large vessel occlusion. There is a small risk of neovascularization, both retinal and choroidal.

Adult↗
PubMed1996

Iatrogenic choroidal neovascularisation following argon laser photocoagulation for choroidal malignant melanoma.

BACKGROUND: Choroidal neovascularisation is known to occur following photocoagulation for choroidal melanomas. Its occurrence rate, possible causes and clinical impact were studied. METHODS: Post-treatment fluorescein angiograms were reviewed from 18 patients who had received argon laser photocoagulation as sole treatment of their small choroidal melanomas, to look for choroidal neovascularisation. Where it was found an assessment of its clinical impact was made. RESULTS: choroidal neovascularisation was found in 50% of cases. Choroidoretinal neovascularisation, found in five patients, caused vitreous haemorrhage in one patient but was otherwise benign. Choroidovitreal neovascularisation was found in four patients. It occurred early and altered their clinical management. Three of these patients had a vitreous haemorrhage, one of whom also suffered a retinal detachment. The three diabetic patients in the series all developed aggressive choroidovitreal neovascularisation. Tumour size, tumours location and number of treatment sessions did not appear to affect the occurrence of choroidal reovascularisation, nor did other medical or ocular conditions except for diabetes. CONCLUSION: Choroidal neovascularisation occurs commonly after melanoma photocoagulation. Although sometimes benign, it can be aggressive, particularly in diabetic patients, in whom it might be better to consider different forms of tumour treatment.

Adult↗
PubMed1996

The microvasculature in myeloproliferative disease. A study using retinal fluorescein angiography.

Microvascular occlusion is known to be a feature of myeloproliferative diseases. Acute manifestations are well documented in individuals causing a variety of symptoms. However, it is not known whether ongoing microvascular changes are present in asymptomatic individuals. We investigated this further by using retinal intravenous fluorescein angiography to image the microvasculature in patients with myeloproliferative disease. In our group of patients fluorescein angiography did not show any ongoing microvascular damage. There appears to be no intrinsic retinal vasculopathy in patients with myeloproliferative disease, suggesting that acute symptomatic events are caused by microemboli in an otherwise normal vascular tree.

Adult↗
PubMed1994

Peripheral retinal vasculature in normal Jamaican children.

A prospective study of the peripheral retinal vasculature in a Jamaican cohort of subjects with sickle cell disease has been in progress over a period of 12 years using fluorescein angiography. Various vascular patterns were identified but their significance was unclear since no comparable records were available in subjects of a similar age with normal (AA) haemoglobin genotype. Fluorescein retinal angioscopy and angiography have been performed in 76 haemoglobin AA controls participating in the cohort study. The peripheral retinal capillary bed could be seen and photographed in a limited portion of the temporal peripheral fundus in a majority of this group, and there was considerable variation in the vascular pattern which could be characterised. These observations allow deviations from normal to be identified in the retinal vasculature in subjects with sickle cell disease.

Adolescent↗
PubMed1994

New classification of peripheral retinal vascular changes in sickle cell disease.

The systemic complications of homozygous sickle cell disease (SS) are more severe than in sickle cell haemoglobin C (SC) disease, and yet visual loss due to proliferative retinopathy is more common in the latter. This anomaly is unexplained. It is believed that proliferative disease occurs in response to closure of the peripheral retinal vasculature, yet a systematic longitudinal survey of the peripheral retinal vascular bed has not been undertaken. In the Jamaica Sickle Cohort study all subjects are scheduled to receive annual ocular examination and fluorescein angiography. The results have now been analysed in subjects with SS and SC disease using a new classification system based on a comparison of the peripheral retinal vascular bed with that recorded in the cohort with normal haemoglobin (AA) genotype. The vascular patterns could be classified as qualitatively normal (type I) or abnormal (type II). An abnormal vascular pattern was identified more commonly with age, in a significantly larger proportion of subjects with SC than SS disease, and was associated with the development of proliferative disease. In order to establish the dynamics of change, the angiograms were analysed in the 18 subjects (24 eyes) who developed proliferative disease. It is shown that a qualitatively normal vascular pattern may be retained despite loss of capillary bed and posterior displacement of the vascular border. A border which is qualitatively abnormal does not revert to normal, and once abnormal, continuous evolution may occur before development of proliferative lesions. The peripheral border of the retinal vasculature was too peripheral to photographed in 13 of the 24 eyes before it becoming qualitatively abnormal. It is concluded that a normal border, if posterior, results from gradual modification of the capillary bed and indicates low risk of proliferative disease. A qualitatively abnormal vascular border occurs as a radical alteration of retinal perfusion in subjects in whom little modification of the vascular bed occurred before the event, and signals risk of proliferative disease. This classification system is useful in identifying the likelihood of threat to vision in young Jamaicans with sickle cell disease, and the higher frequency of proliferative retinopathy in SC can be explained by the higher prevalence of a qualitatively abnormal peripheral retinal vasculature.

Adolescent↗
PubMed1993

A case of ocular ischaemic syndrome in a young insulin dependent diabetic male.

It is well known that diabetic patients are at an increased risk of the earlier development of significant atherosclerotic disease. We wish to report the case of a young insulin-dependent diabetic with an 18 months history of rapidly progressing 'diabetic' retinopathy who presented with right-sided weakness and was found to have severe carotid artery disease. We suggest that the sudden proliferation in his retinopathy was due to retinal ischaemia secondary to the carotid artery stenosis and we wish to present this as a case of ocular ischaemic syndrome in a young diabetic patient.

Adult↗