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T J Ffytche

Publications and source records attributed to T J Ffytche.

At least 19 recordsLinked to original sources
PubMed1996

Breakdown of the blood-aqueous barrier after argon laser panretinal photocoagulation for proliferative diabetic retinopathy.

BACKGROUND: Breakdown of the blood-aqueous barrier (BAB) after panretinal photocoagulation (PRP) was measured with a laser flare photometer over a study period of 8 weeks. METHODS: Twenty-five eyes of 25 patients who had no previous photocoagulation and required such treatment for proliferative diabetic retinopathy (PDR) were included in the trial. They received 2000 burns (0.1-second exposure, 200 mu m spot) via a panfunduscope and 500 burns (0.1-second exposure, 500-mu m spot) with a Goldmann lens. Power levels were adjusted to produce a mild blanching of the retina. Only an argon green laser (514 nm) was used. Laser photometry was performed on both eyes at 3, 24, 48, 72, 96, and 168 hours and 8 weeks after laser treatment. RESULTS: Including all of the eyes treated, there was a significant increase in flare value of 3, 24, and 48 hours compared with baseline (Student's t test) but not at 72, 96, and 168 hours or at 8 weeks. Peak values occurred at 24 hours. When blue and brown irides were analyzed separately, there was a significant increase in flare for blue irides compared with baseline levels at 3 and 24 hours, whereas for brown irides the increased flare was sustained at 3, 24, 48, 72, and 96 hours (Student's paired t test). In addition, when the increase in flare value from baseline was compared between blue and brown irides (pooled Student's test), there was a sustained increase at 24, 48, 72, and 96 hours for brown irides compared with blue. Clinically significant uveitis, posterior synechiae, or peripheral anterior synechiae did not develop in any of the patients. CONCLUSIONS: Breakdown of the BAB may occur after PRP, particularly in more heavily pigmented irides. The time course of this suggests that the phenomenon is related directly to laser effects in the anterior segment, although other factors may contribute.

Anterior Eye Segment↗
PubMed1995

Foveal involvement and lack of visual recovery in APMPPE associated with uncommon features.

Acute posterior multifocal placoid pigment epitheliopathy (APMPPE) is commonly believed to be a benign disease with excellent visual prognosis. Identification of cases with poor visual outcome prompted this retrospective study of 33 eyes of 18 patients with this disorder. Loss of visual acuity at presentation was recorded in 25 eyes (76%), 22 of which had lesions at the fovea. Visual acuity quickly returned to normal or near normal levels (even when it was as poor as counting fingers at entry) in all but 7 eyes of 7 patients, in which visual acuity failed to recover to better than 6/24 over a period of several months. All these eyes had poor acuity and foveal involvement when first seen, and at least one of the following atypical features: age older than 60 years, unilaterality, an interval before involvement of the second eye of at least 6 months, recurrence of the disease, leakage from choroidal vein. One additional patient whose foveae were initially not involved lost vision in one eye because of the development of choroidal neovascularisation. Caution should be exercised in giving a prognosis in cases when the fovea is involved and the acuity markedly reduced, particularly if one or more atypical features is present.

Adolescent↗
PubMed1994

Studies of the blood-aqueous barrier in diabetes mellitus.

We measured the breakdown of the blood-aqueous barrier in 63 patients with diabetes (126 eyes) by using a laser flare meter. Of 126 eyes, 40 had no retinopathy, 34 had proliferative retinopathy, 24 had regressed proliferative retinopathy, 14 had background retinopathy, and 14 had maculopathy. Eyes were classified into one category only. Mean flare was greater for proliferative retinopathy compared to background retinopathy (P = .0065), no retinopathy (P = .0001), and maculopathy (P = .0189). Flare values were greater for regressed proliferative retinopathy compared to no retinopathy (P = .0118) (paired Student's t-test). Diabetic eyes without demonstrable retinopathy still had higher flare values than control eyes without diabetes. The length of diabetes was greater for those eyes with proliferative diabetic retinopathy (P = .0195), regressed proliferative diabetic retinopathy (P = .0625), and background diabetic retinopathy (P = .006) compared to those with no retinopathy. No significant difference was noted in duration of diabetes for eyes with diabetic maculopathy when compared to those with no retinopathy (P = .5788). Breakdown of the blood-aqueous barrier precedes the development of retinopathy, and the more severe proliferative forms have greater blood-aqueous barrier dysfunction.

Adult↗
PubMed1993

Long-term follow-up of diode laser trabeculoplasty for primary open-angle glaucoma and ocular hypertension.

BACKGROUND: Initial studies of laser trabeculoplasty using infrared energy (810 nm) emitted by diode semi-conductor lasers have been encouraging. A 2-year study of diode laser trabeculoplasty (DLT) in the control of primary open-angle glaucoma (POAG) and ocular hypertension has been completed. METHODS: Patients with uncontrolled POAG or ocular hypertension were treated with DLT to one half of the trabecular meshwork using a trabeculoplasty lens. Spot size was 100 microns, exposure time was 0.2 second, and mean power was 1096 mW (+/- 46.5 mW). The desired endpoint was a mild blanching of the meshwork only. RESULTS: Twenty-five eyes of 16 patients were treated. Mean intraocular pressure reduction was 9.24 mmHg (+/- 3.4 mmHg) at 6 weeks, 9.32 mmHg (+/- 3.6 mmHg) at 3 months, 9.34 mmHg (+/- 3.8 mmHg) at 6 months, 8.42 mmHg (+/- 2.62 mmHg) at 12 months, 8.14 mmHg (+/- 3.42 mmHg) at 18 months, and 7.9 mmHg (+/- 3.63 mmHg) at 24 months. No pressure peaks (> 5 mmHg) were recorded after therapy. Inflammation and discomfort were minimal after laser treatment. Of 16 eyes examined at 2 years, there were no peripheral anterior synechiae. During the course of the study, six eyes became uncontrolled, despite one session of DLT. Four eyes regained control with a further session of DLT, but two required trabeculectomy. CONCLUSION: Diode laser trabeculoplasty is an effective form of therapy in POAG and ocular hypertension. Hypotensive effects and success rates are comparable with argon laser trabeculoplasty (ALT). Reduced inflammation after laser treatment may be due to reduced absorption of infrared energy by the melanin of the anterior segment. The portable nature of these lasers may allow for laser delivery in developing countries and remote situations.

Aged↗
PubMed1993

Comparison of the anterior chamber inflammatory response to diode and argon laser trabeculoplasty using a laser flare meter.

BACKGROUND: Diode laser trabeculoplasty (DLT) has a similar hypotensive action to argon laser trabeculoplasty (ALT). However, anterior chamber inflammatory response and laser-induced discomfort are less pronounced with DLT. The authors compared the breakdown of the blood-aqueous barrier after DLT and ALT over the time course of 1 week and the hypotensive action over 8 weeks. METHODS: Twenty-five patients with uncontrolled intraocular pressure (IOP) were randomized to either DLT or ALT. If two eyes required treatment, then the second eye would be treated with the alternative laser to the first. Flare values were measured at 1, 3, 24, 48, 72, 96, and 168 hours using a laser flare and cell meter. Intraocular pressures were measured at similar intervals and at 8 weeks. RESULTS: Of 38 eyes treated, 21 underwent ALT and 17 DLT. Both forms of treatment induced a similar hypotensive effect with a significant reduction in IOP at 8 weeks compared with initial IOP (P < 0.01) (paired Student's t test). However, there was a significantly greater disruption of the blood-aqueous barrier with ALT when compared with DLT at 1, 3, and 24 hours (P < 0.001) and at 48, 72, and 96 hours (P < 0.01) (unpaired Student's t test). By 1 week, however, there was no significant difference in flare values between the two groups. Postlaser pain occurred in seven eyes treated with ALT but in no eyes treated with DLT. In addition, peripheral anterior synechiae occurred in four eyes after ALT by 8 weeks but none occurred in the DLT group. CONCLUSION: Argon laser trabeculoplasty produces a greater disruption of the blood-aqueous barrier than DLT. This may be associated with the development of complications in the anterior segment.

Aged↗
PubMed1992

Ultrastructural changes of human trabecular meshwork after photocoagulation with a diode laser.

A diode laser, which emitted infrared radiation at a wavelength of 810 nm, was used to perform trabecular photocoagulation in a human eye due for enucleation for malignant melanoma. For comparison, burns were applied with an argon blue-green laser (488-514.5 nm). With each laser, the treatment spot size was 100 microns and the pulse duration was 0.20 sec. Visible lesions were produced with a power of between 750 mW and 1.2 W with the diode laser, and 500-900 mW with the argon laser. The pattern of damage produced by both modalities was similar and essentially consisted of contraction or expansion of trabecular beams, with trabecular destruction occurring only in relation to high power exposures. These findings confirm that trabecular photocoagulation is not a process that depends upon the wavelength of the incident energy at the two spectral extremes of 488 nm and 810 nm.

Aged↗
PubMed1991

Residual sight-threatening lesions in leprosy patients completing multidrug therapy and sulphone monotherapy.

An analysis of data derived from standardized surveys of the ocular findings in cross-sections of the leprosy population in 23 areas is presented. It shows that 24.3% of the patients completing multidrug therapy and 32.9% of those completing sulphone monotherapy have on-going eye problems which have the potential to lead to blindness or severe visual impairment. Most of the ocular complications involve the lids, cornea and anterior uveal tract, but a significant proportion of patients had cataract threatening vision. If left unsupervised, many of these patients will develop major visual problems which could have been avoided. It is important that completion of systemic leprosy therapy should not be regarded as a guarantee that the eyes are safe, and that regular ocular supervision should be continued long after the patient has been classified as 'cured'.

Drug Therapy, Combination↗
PubMed1990

Diode laser trabeculoplasty (DLT) for primary open-angle glaucoma and ocular hypertension.

A pilot study has been carried out to examine the efficacy of diode laser trabeculoplasty in the treatment of primary open-angle glaucoma and ocular hypertension. The device used was portable and could be attached to a standard slit-lamp microscope. Powers of 0.8-1.2 W were used, with a spot size of 100 microns and a pulse of 0.20 second. Laser trabeculoplasty carried out on 20 eyes for glaucoma resulted in a mean ocular hypotensive effect of 10.2 mmHG at two weeks after treatment and of 9.55 mmHg at 6 months. It is concluded that diode laser trabeculoplasty is an effective mode of treatment for eyes with open-angle glaucoma or with ocular hypertension.

Aged↗
PubMed1989

Initial clinical experience using a diode laser in the treatment of retinal vascular disease.

A pilot study has been carried out to investigate the clinical use of an infrared diode laser in the treatment of a number of retinal vascular conditions. A hand-held device was employed initially and subsequently a further prototype was developed for use in conjunction with a standard slit lamp microscope. Thirty-three eyes in thirty patients were treated for conditions such as proliferative diabetic retinopathy, exudative retinopathy and branch and central retinal vein thrombosis. Regression of neovascularisation was observed in 13 of 16 eyes (81%) with proliferative diabetic retinopathy and in six of eight eyes (75%) with branch retinal vein occlusion. Four eyes were successfully treated for established or incipient rubeosis iridis following central vein thrombosis. Focal photocoagulation applied to five eyes for diabetic exudative maculopathy resulted in partial resorption of the exudates. These results are presented together with information on the ease of use of the laser and its reliability. The implications of the development of this instrument in the context of its place in ophthalmic therapy are discussed.

Aged↗
PubMed1985

Ocular leprosy.

Explore the source record for details and available documents.

Ciliary Body↗
PubMed1981

Role of iris changes as a cause of blindness in lepromatous leprosy.

Clinical and pathological investigations in a group of 113 patients with leprosy of long duration demonstrated the importance of iris changes as a cause of blindness. In lepromatous leprosy the so called "chronic iritis" produces iris atrophy with small nonreacting pupils which exaggerate the visual impairment created by developing lens changes and corneal opacities. The cause of this "chronic iritis" is believed to be neuroparalytic from early involvement of the small nerves of the iris, particularly the autonomic supply. Clinical and pharmacological evidence for this theory is supported by the histological changes observed in 18 specimens of iris removed during the course of cataract surgery, with progressive atrophy of the iris preferentially affecting the dilator muscle and leading to a nonreacting miosed pupil. Further pharmacological and histological studies are to be undertaken on lepromatous patients with iris involvement with a view to establishing possible methods of prevention.

Aged↗
PubMed1981

Cataract surgery in the management of the late complications of lepromatous leprosy in South Korea.

Clinical examination of 113 patients in South Korea with lepromatous leprosy and severe visual impairment showed that the main cause of visual loss was the combined effect of corneal and lens opacities associated with small nonreacting pupils and iris atrophy. Cataract surgery with broad iridectomy and inferior sphincterotomy offers these patients with chronic lepromatous complications the best chance of preserving vision. Eighty-one cataract operations were performed under local anaesthesia, and in 90% vision improved; in 60% this improvement was 2 Snellen's lines or more.

Adult↗
PubMed1981

Iritis in leprosy.

Iritis in leprosy is still a significant cause of blindness and visual impairment in this disabling disease. Evidence is accumulating from clinical observations and from pathological and pharmacological studies that the chronic iritis of lepromatous leprosy may have a neuroparalytic origin. A hypothesis derived from this evidence is presented in order to stimulate further research into the pathogenesis of this condition with a view to developing new methods of management and prevention.

Acute Disease↗