Biomedical subjects

H I Alanko

Publications and source records attributed to H I Alanko.

10 recordsLinked to original sources

PubMed1992

Rate and pattern of neuroretinal rim area decrease in ocular hypertension and glaucoma.

The neuroretinal rim areas of 123 eyes (from five normal subjects, 75 patients with ocular hypertension, and 43 patients with glaucoma) were measured to determine the rate and pattern of rim area change during 5 to 15 years (mean, 10 years) of follow-up. Fifty-seven percent of the patients with ocular hypertension and 79% of those with glaucoma showed a statistically significant slope of rim area decrease, a high rate of loss being associated with a high initial rim area. Ninety percent of the variation of rim area loss was accounted for by variables other than the ones measured herein, however (age, disc area, initial rim area, and intraocular pressure). The yearly loss of rim area was 0.23% of the initial area in normal subjects, 0.47% and 2.75% in the patients with stable and deteriorating ocular hypertension, respectively, and 3.47% in the patients with deteriorating glaucoma. The pattern of rim area change was linear in 49% of the patients with a statistically significant rim area decrease, episodic in 22%, and curvilinear in 29%.

Adult↗

PubMed1992

Neuroretinal rim area measurements by configuration and by pallor in ocular hypertension and glaucoma.

PURPOSE: The purpose of this study is to examine the differences between measurements of neuroretinal rim area of the optic disc defined by configuration and by pallor. METHODS: One hundred seventy-one patients were studied (59 with glaucoma, 96 ocular hypertensive patients, and 16 controls). The magnification-corrected neuroretinal rim area was measured from black-and-white stereoscopic paper prints. The central area of pallor was measured using computer-assisted image analysis techniques. The percentage of central area of pallor was converted into mm2, and an estimate of neuroretinal rim area defined by color was calculated. RESULTS: The correlation between the measurements of neuroretinal rim area by configuration and by pallor was statistically highly significant (r = 0.89, P less than 0.0001). No consistent differences between measurements were found in different diagnostic groups, or in different stages or types of glaucomatous optic disc abnormality. The correlation of changes of both measurements during a 9-year follow-up period also was statistically significant (r = 0.68, P less than 0.001). CONCLUSION: In clinical routine measurements of the neuroretinal rim area, using both configuration and pallor definition does not seem to add to the information.

Adult↗

PubMed1991

Lens autofluorescence in healthy individuals.

We measured blue-green autofluorescence (AF, 495 nm/520 nm) of the lens in 43 random eyes of 43 healthy volunteers aged 6-86 years, five in each decade, using an instrument designed by one of us (HN). The instrument generates an autofluorescence profile, which consists of anterior and posterior juxtacortical peaks and a central plateau. The height of the anterior peak was taken as a maximum autofluorescence value and the square root of the ratio between the posterior and the anterior peak was used as a lens transmission index. The coefficient of variation for the measurement technique was 3.9% for maximum autofluorescence and 2.9% for lens transmission index. Both the maximum autofluorescence and the transmission index were highly correlated with age. Statistically over 90% of the variation in maximum autofluorescence values and almost 70% of the variation in transmission could be attributed to age.

Adolescent↗

PubMed1991

Neuroretinal rim area in low tension glaucoma: effect of nifedipine and acetazolamide compared to no treatment.

The purpose of this study was to measure the change of neuroretinal rim area in patients with low tension glaucoma on- and off-treatment. Thirty-two patients were followed up for a mean of 2.6 years. Ten patients received treatment with nifedipine, 11 patients with acetazolamide and 11 patients had no treatment. The total change of rim area and the yearly rate of rim area change did not differ statistically significantly between the three groups. Seven patients in each group suffered from cold hands and feet. The response to cold provocation visual field testing was positive in 25% of patients. Neither the history of cold hands and feet nor the cold provocation test result affected the rate of progression of optic disc abnormalities. Nifedipine and acetazolamide treatment seemed to show no advantage over no-treatment in our patients.

Acetazolamide↗

PubMed1990

Retinal nerve fiber layer abnormalities and high-pass resolution perimetry.

The purpose of this study was to compare high-pass resolution perimetry (HRP) test results with clinical optic disc measurements and semi-quantitative retinal nerve fiber layer (RNFL) estimates. HRP reflects the separation of functional ganglion cells in the retina, and estimates a 'Functional Channel Fraction (FCF)' index that expresses the number of functional ganglion cells relative to average normal. FCF was statistically highly significantly correlated both with the overall and diffuse RNFL score (r = -0.63, P less than 0.0001) and with the neuroretinal rim area (r = 0.44; P less than 0.001). This suggests that HRP is a useful psychophysical test to assess optic nerve integrity in glaucoma.

Adult↗

PubMed1989

Laser trabeculoplasty versus medication treatment as primary therapy for glaucoma.

The first-year results of a 5-year prospective randomized follow-up study on 39 glaucoma patients, of whom 19 patients received laser trabeculoplasty and 20 patients medication therapy as primary treatment of their newly detected open-angle glaucoma, are presented. The optic disc changes were recorded by measuring the magnification corrected neuroretinal rim area from stereoscopic optic disc photographs and the visual field changes with an automated perimeter. There were no statistically significant differences in success rate, intraocular pressure reduction, and optic disc or visual field changes between the two groups during the first year of follow-up. In half of the laser treated patients the intraocular pressure was below 22 mmHg without medication treatment. Many patients in the medication group required frequent modifications of their therapy. Laser trabeculoplasty has an important role as primary therapy in glaucoma.

Acetazolamide↗

PubMed1988

Prevalence of exfoliation syndrome in Finland.

Three separate investigations are reported, covering a total of 795 patients from different parts of Finland, two of them consisting of inmates of old people's homes in two towns (N = 205 and 262) and one a randomly selected population from a rural commune (N = 328). They show the mean prevalence of exfoliation syndrome (PS) to be 14.2% in age group 60 less than or equal to 69 years, 21.9% in age group 70-79 and 34.7% in age group greater than or equal to 80. The prevalence increases statistically significantly with age. The mean prevalence of PS in all three groups was 22.4%. No isolate-like accumulation of PS could be demonstrated. The figures seem representative of the hole country.

Age Factors↗

PubMed1987

A controlled five-year follow-up study of laser trabeculoplasty as primary therapy for open-angle glaucoma.

We followed up 32 eyes of 32 patients with early glaucoma (22 with capsular glaucoma and ten with simple glaucoma) who received laser trabeculoplasty as a primary therapy. These eyes were compared with a matched control group of 32 eyes treated with medication initially. The success rate (intraocular pressure below 22 mm Hg with laser alone or medication alone) at five years was 50% (16 of 32 eyes) in the laser-treated group and 22% (seven of 32 eyes) in the control group (P less than .02). The control group required more modifications of their therapy to control intraocular pressure. The neuroretinal rim area in the control eyes decreased 2.5 times as much as in the laser group (P = .017). Changes in the Friedmann visual fields did not differ significantly between the two groups.

Aged↗

PubMed1986

Characteristics of corneal endothelial cells in Fuchs' heterochromic cyclitis.

We studied the corneal endothelial cells in 14 patients (6 men and 8 women, ranging in age from 15 to 70 years) with unilateral Fuchs' heterochromic cyclitis (FHC) by means of specular microscopy. The healthy fellow eyes of the patients served as control material. Two affected eyes had undergone an intracapsular cataract extraction before specular microscopy. In one patient, the cyclitic eye also had glaucoma. Changes of the endothelium characterized by intra- and intercellular dark bodies, larger dark defects spanning several endothelial cells and bright irregular patchy areas crossing cell borders on the specular reflex were found in all eyes with FHC. Individual cell analysis did not reveal any significant differences in the endothelial cell density, cell area, coefficient of variation for cell area, cell perimeter, cell shape and in the number of endothelial cell apices between unoperated cyclitic and healthy fellow eyes. The mean cell density was 4.9% lower in the unoperated eyes with FHC than in the control eyes. A significant negative correlation was observed between the patients' age and the cell density both in the healthy and the cyclitic eyes. On the other hand, the correlation between follow-up period and cell density was not statistically significant in the cyclitic eyes. Although FHC does not seem to accelerate significantly the age-related cell density reduction, the magnitude of the cell loss found in the two operated eyes (45.5% and 49.8%) and in the eye with glaucoma (45.2%) may indicate altered tolerance against endothelial traumas in this disease.

Adolescent↗

PubMed1986

Dislocated intraocular lens after biodegradation of fixation loops. A case report.

A boy aged 3 years had a Worst Medallion intraocular lens with loops made of nylon 6 implanted in his right eye after aspiration of traumatic cataract. Post-operatively, the eye was irritated and showed increased tendency to secondary membrane formation. The patient was lost to follow-up 3 months post-operatively. He returned 5 years later because of 4 days of pain and redness in his right eye. On examination, the optic part of the intraocular lens was seen to lie free in the anterior chamber. The loops were broken near their insertions in the lens body. The distal ends of the broken loops could not be detected in the pupillary region. No traces of the iris fixation suture were to be seen. The lens was removed and subjected to scanning electron microscopy which revealed extensive biodegradative changes in the 3 loop stumps, the 4th being totally dissolved. The young age of the patient and the chronic inflammation may have had an accelerating effect on the nylon degradation. We conclude that children with eyes implanted with nylon-loop lenses should stay under regular ophthalmological control.

Anterior Chamber↗