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N V Nielsen

Publications and source records attributed to N V Nielsen.

At least 19 recordsLinked to original sources
PubMed2001

[Age related macular degeneration. A widespread disease].

Age-related macular degeneration, AMD, is the commonest cause of legal blindness in the industrialised world. Epidemiological data suggest that in Denmark more than 80,000 persons suffer impaired vision in at least one eye, because of AMD. More than 4000 are legally blind owing to this disease. AMD has two major phenotypes: wet and dry. Most severe visual losses are caused by wet AMD, where new blood vessels form under the macula. A new treatment of this condition is now available. Photodynamic therapy with verteporfin has been investigated in a double-blind, randomised clinical trial with more than 600 patients. This study has been scrutinised by a Cochrane review, which has recommended criteria for the treatment. For eyes meeting these inclusion criteria, photodynamic therapy can reduce the occurrence of moderate and severe visual loss over a two-year period by more than 60%. It is estimated that around 1000 eyes in Denmark will meet the inclusion criteria for photodynamic therapy.

Age Factors↗
PubMed2001

Diabetic retinopathy in newly diagnosed middle-aged and elderly diabetic patients. Prevalence and interrelationship with microalbuminuria and triglycerides.

BACKGROUND: The exact role of factors such as serum lipids, body mass index and (micro-)albuminuria as possible determinants of diabetic retinopathy remains to be determined. We have scrutinized the prevalence of diabetic retinopathy and its concomitants in terms of risk factors and other diabetic complications in newly diagnosed diabetic patients. METHODS: A population-based sample of 1,251 newly diagnosed diabetic patients aged 40 years or over was established in general practice. Median age was 65.3 years. Funduscopy was performed by practising ophthalmologists. Blood and urine analyses were centralised. RESULTS: The overall prevalence of diabetic retinopathy was 5.0%. Only three patients had proliferative diabetic retinopathy. As expected, diabetic retinopathy and renal involvement, as expressed by the urinary albumin/creatinine ratio. were strongly positively associated. An intriguing finding was that of an inverse relationship between fasting triglycerides and diabetic retinopathy, an association that proved to be confined to microalbuminuric patients. An inverse association between body mass index and diabetic retinopathy was found only univariately. CONCLUSION: The low prevalence of diabetic retinopathy cannot be explained by the screening method alone, but rather by early detection of diabetes in a non-selective patient sample. It seems that renal involvement modifies the expected relationship between diabetic retinopathy and triglycerides, but a pathophysiological mechanism is not available.

Aged↗
PubMed2001

Prevalence and causes of visual impairment according to World Health Organization and United States criteria in an aged, urban Scandinavian population: the Copenhagen City Eye Study.

PURPOSE: To evaluate the prevalence and causes of visual impairment in an epidemiologic study of aged, urban individuals in Denmark. DESIGN: Cross-sectional study. PARTICIPANTS: The study population consisted of 1000 randomly selected residents aged 60 to 80 years in Copenhagen, Denmark. Of 976 eligible persons, 946 (96.9%) could be examined. Information about best-corrected visual acuity (VA) was obtained from 944 cooperative persons (96.7%). METHODS: Data from the Copenhagen City Eye Study were used to assess the cause-specific prevalence of visual impairment as defined by the World Health Organization (WHO) (VA worse than 20/60-20/400 in the better eye) and the criteria used most commonly in the United States (VA worse than 20/40 but better than 20/200 in the better eye). Eligible subjects underwent an extensive ophthalmologic examination at The National University Hospital of Denmark. MAIN OUTCOME MEASURES: Best-corrected VA and primary causes of visual impairment. RESULTS: The prevalence of low vision according to the WHO definition ranged from 2.6% in subjects aged 70 to 74 years to 4.8% in subjects 75 to 80 years of age, with an age-adjusted relative prevalence of 1.58%. Using the U.S. definition, the overall age-adjusted prevalence of visual impairment was 2.9%. The causes of visual impairment according to the WHO criteria were age-related macular degeneration (AMD) (44.4%), cataract (33.3%), glaucoma in combination with cataract (11.1%), myopic macular degeneration (5.6%), and diabetic retinopathy (5.6%). However, according to the U.S. criteria, cataract was the most frequent primary cause (50.0%) and AMD was the second most frequent primary cause (34.4%) of visual impairment. Furthermore, using the U.S. criteria diabetic retinopathy was revealed as equally important as AMD and cataract as a cause of visual impairment among persons aged 65 to 69 years (33.3%). CONCLUSIONS: Increasing age was an independent predictor of visual impairment. Cataract and AMD were the leading causes. Adequate implementation of surgery to treat cataract could reduce visual impairment by 33.3% according to the WHO criteria and by 50% according to the U.S. criteria.

Age Distribution↗
PubMed2001

The prevalence and causes of bilateral and unilateral blindness in an elderly urban Danish population. The Copenhagen City Eye Study.

PURPOSE: To study the prevalence and causes of bilateral and unilateral blindness in an elderly urban Danish population. METHODS: Data originated from a Danish epidemiologic cross-sectional random sample population eye survey conducted during the years 1986-1988. The population consisted of 1,000 inhabitants aged 60 to 80 years in Copenhagen. The participants underwent an extensive ophthalmologic examination. A participation rate of 96.9% was achieved. Any blindness was defined as best-corrected visual acuity (VA) worse than 0.05 (the WHO criteria) and VA of 0.1 or worse (the National criteria (NC) of blindness). RESULTS: The prevalence rates of bilateral and unilateral blindness were, respectively, 0.53% and 3.38% according to WHO, but 1.06% and 4.44% using NC. Bilateral blindness rose significantly with age (p=0.02). According to NC, age-related macular degeneration (AMD) was the leading cause of bilateral blindness, accounting for 60% of all blind persons. Glaucoma, myopic macular degeneration, cataract and retinitis pigmentosa were jointly the second most common cause, each accounting for 10% of all bilaterally blind persons. Diabetic retinopathy was not a cause of bilateral blindness. Amblyopia was the most frequent, AMD the second most frequent, and diabetic retinopathy was among the third most common cause of unilateral blindness accounting for, respectively, 28.60%, 16.66% and 9.52% of all unilateral blindness. CONCLUSIONS: Blindness was associated with increasing age. A calculation indicates that among Danes aged 60 to 80 years 7,736 are bilaterally blind and 35,503 suffer from unilateral blindness. This study highlights AMD as the most important cause.

Aged↗
PubMed2000

HSV-1--induced acute retinal necrosis syndrome presenting with severe inflammatory orbitopathy, proptosis, and optic nerve involvement.

OBJECTIVE: To present a unique case in which orbital inflammation, proptosis, and optic neuritis were the initial symptoms of acute retinal necrosis (ARN). The clinical presentation of ARN, as well as the currently recommended diagnostic procedures and guidelines for medical treatment of ARN, are summarized. DESIGN: Interventional case report. TESTING: Polymerase chain reaction (PCR) techniques were made on the vitreous for cytomegalovirus, Epstein-Barr virus, herpes simplex virus (HSV), varicella zoster virus, and toxoplasmosis. A full laboratory evaluation was made together with HLA-typing and serologic tests measuring convalescent titers for HSV and other micro-organisms. Magnetic resonance imaging scan, computed tomography (CT) scan, and fluorescein angiographic examination were performed. The patient was treated with acyclovir and oral prednisone. MAIN OUTCOME MEASURES: The patient was evaluated for initial and final visual acuity and for degree of proptosis, periocular edema, and vitreitis. RESULTS: The first symptoms and signs of ARN were eye pain, headache, proptosis, and a swollen optic nerve on CT scan. Other than increased C-reactive protein, all blood samples were normal. PCR was positive for HSV-type I in two separate vitreous biopsies. The patient had the strongly ARN-related specificity HLA-DQ7. CONCLUSIONS: This is the first report of HSV-induced ARN presenting with inflammatory orbitopathy and optic neuritis. Polymerase chain reaction for HSV-1 was positive more than 4 weeks after debut of symptoms, which is a new finding. The combination of severe vitreitis and retinal whitening, with or without proptosis, should alert the clinician to the possibility of herpes infection and treatment with intravenous acyclovir started promptly.

Acyclovir↗
PubMed1999

Pachometry before and after vitrectomy with silicone oil injection.

PURPOSE: To evaluate differences in central corneal thickness (CCT) before and after vitrectomy with injection of silicone oil as vitreous substitution material in order to determine whether silicone oil causes more frequent and/or pronounced corneal decompensation than other substitution materials. METHODS: CCT was measured by ultrasonic pachometry in 42 eyes. 25 eyes received injection of silicone oil and 17 eyes C3F8, atmospheric air or saline. Measurements were performed 24 hours pre operatively, during anaesthesia pre operatively and 24 hours, 48 hours and five months post operatively. RESULTS: A progressive central corneal thickening could be demonstrated in both groups. Eyes which received silicone oil showed maximum CCT increase of 0.083 mm (14.1%) 48 hours post operatively. At follow-up CCT had decreased to baseline value in both groups. Silicone oil did not induce CCT changes that were significantly different from those induced by other substitution materials. CONCLUSION: Silicone oil injection in detachment surgery induces reversible corneal decompensation to the same degree as other substitution materials within the first five months post operatively.

Adult↗
PubMed1997

[Retinal detachment. The vitrectomy technique].

One hundred and ten eyes from 110 patients who in 1992 had undergone vitrectomy for regmatogenous retinal detachment were included in a retrospective study. Two year follow-up was obtained for 97 eyes. At the end of follow-up 45% of the eyes had complete anatomical success. Fifty-five percent had attachment of the macula. Anatomical success after a single operation was obtained in 33%. A visual acuity of more than 0.05 was obtained for 35% of the eyes at the end of follow-up. Eighty patients had a follow-up interview; of these 56% stated that the advantages of the operation outweighed the disadvantages.

Adolescent↗
PubMed1997

[Retinal detachment. The scleral buckling technique].

Eighty-four eyes from 83 patients who in 1992 had undergone scleral buckling surgery for rhegmatogenous retinal detachment were included in a retrospective study. Two year follow-up was obtained for 72 eyes. At the end of follow-up 93% of the eyes had complete anatomical success. A visual acuity of 0.5 or more was obtained for 45% of the eyes at the end of follow-up. Sixty-three patients stated that the advantages of the operation outweighed the disadvantages.

Adolescent↗
PubMed1994

Central retinal artery occlusion in a patient with Fabry's disease documented by scanning laser ophthalmoscopy.

Fabry's disease, angiokeratoma corporis diffusum, is an X-linked inborn error of glycosphingolipid metabolism due to lack of activity of the lysosomal enzyme, alpha-galactosidase A, resulting in progressive intracellular deposition of neutral glycosphingolipids in various tissues, including vascular endothelial - and smooth muscle cells. Occlusions of the retinal vessels are rare. We present a case of central retinal artery occlusion in a 25-year-old male with Fabry's disease, documented by fluorescein- and indocyanine green angiography performed by scanning laser opththalmoscopy.

Adult↗
PubMed1994

Retinopathy in type II diabetes mellitus associated with above-normal urinary excretion of RBP.

We performed a cross-sectional study on the urinary excretion profiles of albumin (a marker of glomerular dysfunction) and retinol-binding protein (a low molecular mass protein marker of renal proximal tubular dysfunction) in non-insulin dependent (Type II) diabetics, with or without retinopathy. The urinary excretion of both proteins, in particular retinol-binding protein, was significantly higher in patients with background/proliferative retinopathy compared to patients without retinopathy. The degree of retinopathy correlated to the urinary excretion of albumin (P < 0.005) and retinol-binding protein (P < 0.0001). Retinopathy occurred at a higher frequency in patients with above-normal urinary excretion of retinol-binding protein, both in the absence or presence of micro/macroalbuminuria. The frequency of retinopathy among micro/macroalbuminuric patients with a normal urinary excretion of retinol-binding protein did not differ significantly from that observed in patients with a normal urinary excretion of both proteins. We cannot explain the association between retinopathy and proximal tubular dysfunction in Type II diabetes. However, it is possible that both phenomena are related to a common pathogenetic factor.

Aged↗
PubMed1993

Low-molecular-mass proteinuria as a marker of proximal renal tubular dysfunction in normo- and microalbuminuric non-insulin-dependent diabetic subjects.

We determined the urinary excretion, expressed as the protein/creatinine ratio (morning urines), of albumin (a marker of glomerular dysfunction) and retinol-binding protein (RBP; a low-molecular-mass protein marker of tubular proteinuria) in 102 non-insulin-dependent diabetic patients. There was a statistically significant (P < 0.0001) correlation (rho = 0.38) between the urinary excretion values of the two proteins. The population could be divided into four subgroups: 32 with normal excretion values, 15 with above-normal urinary excretion of RBP, 24 with above-normal urinary excretion of albumin, and 31 patients with above-normal urinary excretion of both proteins. No patients had above-normal serum creatinine concentrations or above-normal serum RBP concentrations. This seems to exclude "tubular overflow proteinuria" as the cause of the increased urinary excretion of RBP seen in some patients with non-insulin-dependent diabetes. Our data suggest the presence of a state of proximal tubular dysfunction in these patients.

Adult↗
PubMed1990

Diabetic retinopathy related to degree of albuminuria and tubular (low molecular weight) proteinuria in insulin-dependent (type I) diabetes mellitus.

The urinary excretion of albumin (a marker of glomerular damage) and retinol binding protein (a low molecular weight protein marker of tubular dysfunction) was determined by sensitive immunochemical methods in 110 insulin-dependent (Type I) diabetic patients. We observed a statistically significant correlation between the urinary excretion levels of both proteins, in particular albumin, and the degree of retinopathy. The incidence of macroalbuminuria and tubular proteinuria was significantly higher in patients with manifest background retinopathy and proliferative retinopathy as compared to patients with no or slight retinopathy. The duration of diabetes was significantly correlated to the degree of retinopathy, but not to the urinary excretion of albumin and retinol binding protein.

Adolescent↗
PubMed1990

Arterial blood pressure related to degree of albuminuria and low-molecular-weight proteinuria in IDDM.

Urinary excretion of albumin and retinol-binding protein (a marker of tubular proteinuria that results from impaired proximal tubular reabsorption of low-molecular-weight proteins) was determined in 110 insulin-dependent diabetic (IDDM) subjects. A statistically significant correlation between the urinary excretion of both proteins, in particular the retinol-binding protein, and the height of arterial blood pressure (systolic and diastolic) was observed. Correlation was weak, i.e., factors other than incipient nephropathy could be of greater importance for the development of arterial hypertension in diabetes.

Adolescent↗
PubMed1988

Relationship between the urinary excretion of albumin and retinol-binding protein in insulin-dependent diabetics.

The glomerular and proximal tubular function of the diabetic kidney was investigated. The urinary excretion (relative clearance) of albumin, a marker of glomerular function, and retinol binding protein (RBP), a low molecular weight (LMW) protein and marker of proximal tubular function, was determined in insulin-dependent diabetics. No correlation between the relative clearances of albumin and RBP was observed. LMW proteinuria without microalbuminuria was observed in 27 patients which suggests that tubular dysfunction may be an early stage in the development of diabetic nephropathy. Microalbuminuria was found in 16 patients while a mixed type of proteinuria (microalbuminuria and LMW proteinuria) was present in 56 patients several of whom had advanced nephropathy with elevated serum levels of RBP and creatinine. It is suggested that a combination of tubular and glomerular malfunction may be responsible for some cases of mixed proteinuria.

Adolescent↗
PubMed1988

Treatment of age-related macular degeneration by laser photocoagulation. Visual results 2-8 weeks and 2-4 years after initial laser treatment.

Laser treatment with blue-green argon, green argon and/or krypton red was performed on 578 eyes in 443 patients with neovascular age-related macular degeneration (AMD). The visual acuity was examined in all eyes 2 to 8 weeks after initial treatment and in 204 eyes in 167 patients 2 to 4 years after initial treatment. The short term results were as follow: 91/578 eyes (16%) had improved (greater than or equal to 2 lines on Snellen's charge or equivalent steps), 445/578 eyes (77%) remained unchanged and 42/578 eyes (7%) had deteriorated visual acuity (greater than or equal to 2 lines on Snellen's chart or equivalent steps). The reduction in visual acuity, may in about half of the 42 eyes be caused by too intensive laser application in the beginning of this study in 1983 and 1984 where treatment was applied with blue-green argon, which has now been abandoned. In the group with an observation time of 2 to 4 years, 42/204 eyes (21%) had improved, 119/204 eyes (58%) remained unchanged and 43/204 eyes (21%) had a deteriorated visual acuity. In the 204 eyes the subretinal neovascular lesion(s) were located extrafoveally in 52 eyes, juxtafoveally in 114 eyes and subfoveally in 38 eyes. It is to be pointed out, that even patients with a pre-laser visual acuity of 6/60 or worse obtained an improvement of visual acuity in 12/27 eyes. About 40% of the eyes needed re-treatment from 1 to 8 times. It is unknown whether the obtained results are to be considered marginal or more substantial.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗