Biomedical subjects
I H Chisholm
Publications and source records attributed to I H Chisholm.
Disciform macular degeneration: a review of the disease and its management.
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The recurrence of neovascularization and late visual failure in senile disciform lesions.
Recurrent disease poses a major problem in the clinical management of neovascular senile macular degeneration. Some visual loss may accompany successful flattening of the neovascular lesion and late visual failure may occur in all cases.
Indications for fluorescein angiography in disease of the ocular fundus: a review.
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Senile disciform macular degeneration: features indicating suitability for photocoagulation.
During a 1-year period 398 new patients were seen with disciform macular degeneration (530 eyes). The lesions were studied retrospectively, and those in which the neovascular tissue did not underlie the fovea, and therefore were treatable, were identified. The following conclusions were drawn: (1) Treatment is possible in most patients with good acuity and few with poor acuity. (2) Treatment is possible in a large proportion of patients with a short history and few with a long history of visual loss. (3) As many as 50% of all patients with senile disciform macular degeneration may be amenable to treatment if seen early enough in the course of their disease. (4) Over one-third of eyes with lesions that are untreated have a visual acuity of 6/60 or better 3 years after the onset of symptoms. (5) If a controlled trial proves that treatment is beneficial, these results emphasise the need for rapid referral and show that these patients will generate a large additional clinical load.
Senile disciform macular degeneration in the second eye.
Development of senile disciform degeneration in the second eye was studied in a group of 104 patients over a period of up to five years. 12 to 15% of these patients develop disciform degeneration in the other eye each year. Patients with large and confluent drusen, especially if combined with accumulation of dye on fluorescein angiogram, were at greatest risk of developing disciform degeneration in the second eye.
The late stage of serpiginous (geographic) choroiditis.
Serpiginous and geographic choroiditis, one and the same disease, is characterized by episodic involvement of the pigment epithelium and choroid. Each new lesion passes through an acute phase into an atrophic and scarring one. We observed 20 patients, some with long-term follow-up; some had eventual widespread involvement of both posterior poles. There was no basis for the disease, and treatment did not affect its course. In the patients with long-term disease there was widespread atrophy of the choroid and pigment epithelium and variable amounts of pigment clumping and subretinal fibrous tissue deposition. In nine patients discrete peripheral patches of atrophy were also found. In some eyes the atrophy at the posterior pole had become so confluent that the condition could have been mistaken superficially for a primary choroidal dystrophy. The uninvolved areas appeared to be normal. The electroretinogram and electrooculogram were only affected when extensive disease was present.
Cortical blindness in cranial arteritis.
A case is presented of cortical blindness in cranial arteritis. A clinical diagnosis at the time of presentation was based on the integrity of the pupillary light reflex and the absence of visually evoked responses. Pathological examination confirmed bilateral occipital infarction. This report stresses the need for recognizing this presentation of cranial arteritis and initiating immediate treatment.
Incidence of aphakic macular oedema. A prospective study.
A prospective angiographic study of 77 aphakic eyes demonstrated cystoid macular oedema in 36 eyes (46-7 per cent) 6 to 7 weeks postoperatively. This subsequently resolved in 16 eyes, improved in eight, and was no better or worse in five (eight patients failed to return for follow-up). Of those patients with cystoid oedema, 16-6 per cent had a visual acuity of less than 6/12 at the time of the original examination; this was reduced to 13-8 per cent at the time of the follow-up study. The mean visual acuity of the group with oedema improved from 6/9 to 6/7-5 between the two examinations compared with 6/6 in the remaining 53-3 per cent without oedema. Preoperative ocular or general disease, specific surgical technique, and vitreous loss were not shown to be associated with macular oedema. However, there was some indication that intraocular inflammation predisposed to macular oedema.
Aphakic macular edema: incidence and pathogenesis.
In a prospective study, the incidence of cystoid macular edema for two groups of patients was found at six weeks following surgery. The first group who underwent cataract extraction had a 50 per cent incidence. The second group who underwent elective glaucoma surgery had no patient with cystoid macular endema. At six weeks, 16 per cent of those patients who had originally developed cystoid edema, had a visual acuity of 6/12 or less, with no other cause for the poor visual result. The two major differences between these two groups of patients were the actual cataract extraction, and the presence of postoperative vitreous inflammation. No factors were noted to cause persistence of the aphakic macular edema although the technique of cataract extraction and vascular disease were implicated.
Choroidal haemangioma, a diagnostic and therapeutic problem.
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Vascular tufts at the pupillary margin in myotonic dystrophy.
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An international classification and grading system for age-related maculopathy and age-related macular degeneration. The International ARM Epidemiological Study Group.
A common detection and classification system is needed for epidemiologic studies of age-related maculopathy (ARM). Such a grading scheme for ARM is described in this paper. ARM is defined as a degenerative disorder in persons > or = 50 years of age characterized on grading of color fundus transparencies by the presence of the following abnormalities in the macular area: soft drusen > or = 63 microns, hyperpigmentation and/or hypopigmentation of the retinal pigment epithelium (RPE), RPE and associated neurosensory detachment, (peri)retinal hemorrhages, geographic atrophy of the RPE, or (peri)retinal fibrous scarring in the absence of other retinal (vascular) disorders. Visual acuity is not used to define the presence of ARM. Early ARM is defined as the presence of drusen and RPE pigmentary abnormalities described above; late ARM is similar to age-related macular degeneration (AMD) and includes dry AMD (geographic atrophy of the RPE in the absence of neovascular AMD) or neovascular AMD (RPE detachment, hemorrhages, and/or scars as described above). Methods to take and grade fundus transparencies are described.