The effect of complement factor H Y402H polymorphism on the outcome of photodynamic therapy in age-related macular degeneration.

PURPOSE: Photodynamic therapy (PDT) has been widely used in the treatment of age-related macular degeneration (AMD). The complement cascade has an important role in the tissue reactions occurring after PDT. The Y402H polymorphism of the complement factor H (CFH) gene has been identified as a risk factor for AMD. Since CFH is central in the regulation of the complement system the authors wanted to analyze whether the CFH Y402H polymorphism modifies the PDT outcome in AMD. METHODS: A total of 88 patients having been treated with PDT and without further scheduled PDT sessions were analyzed. Depending on the situation at their final PDT session the patients were classified retrospectively as PDT-responders or PDT-nonresponders. All patients were genotyped for the CFH Y402H polymorphism. RESULTS: The proportion of PDT-responders was 18/26 (69.2%) in patients homozygous for the CFH Y402H risk allele, 34/50 (68.0%) in heterozygous, and 7/12 (58.3%) in patients with the normal genotype (p=0.520). The median number of PDT treatments of the PDT-responders was three for all the genotypes. CONCLUSIONS: The dysfunction of the CFH related to the risk of AMD and caused by the Y402H polymorphism does not modify the outcome of PDT. Genotyping for CFH Y402H cannot be used to select patients for this treatment.

Inflammatory markers and retinopathy in pregnancies complicated with type I diabetes.

AIM: The relation of maternal cytokine levels to retinopathy progression during diabetic pregnancy is a less studied subject. Therefore, we investigated levels of systemic proinflammatory markers, C-reactive peptide (CRP), interleukin-6 (IL-6) and circulating vascular cell adhesion molecule-1 (VCAM-1) during pregnancy and postpartum in relation to the progression of diabetic retinopathy (DR). METHODS: A prospective follow-up study of 39 pregnant women with Type I diabetes and eight nondiabetic pregnant women was performed. DR was graded from fundus photographs. Plasma levels of systemic proinflammatory markers were measured by immunofluorometric assay (CRP) and by enzyme-linked immunosorbent assay (IL-6 and VCAM-1) in the first, second (diabetics only), third trimester of pregnancy, and 3 and 6 months postpartum (diabetics only). RESULTS: Our diabetic women had good glycaemic control (HbA1c 6.9 +/- 0.8). The levels of IL-6, VCAM-1, and CRP did not differ between diabetic and nondiabetic women throughout pregnancy and postpartum (repeated measures ANOVA between the groups). An association between CRP and progression of retinopathy was observed in diabetic women (P = 0.037). Additional evidence of inter-relationship could be revealed as CRP was higher in those diabetic women with worse glycaemic control (HbA1c) (P = 0.038). CONCLUSIONS: During pregnancy and postpartum, levels of proinflammatory factors (IL-6, CRP, VCAM-1) seem to be generally similar in Type I diabetic women compared to nondiabetic controls. However, CRP levels were higher in those diabetic women with progression of retinopathy and in those with worse glycaemic control.

Angiopoietic factors and retinopathy in pregnancies complicated with Type 1 diabetes.

AIMS: To evaluate the role of systemic angiopoietic factors in the progression of diabetic retinopathy during pregnancy. METHODS: In a prospective study of 26 pregnant women with diabetes and eight non-diabetic pregnant women, retinopathy was graded from fundus photographs. Plasma levels of angiopoietin-1, angiopoietin-2, human vascular endothelial growth factor A (hVEGF-A), and total soluble receptor of vascular endothelial growth factor (sVEGF) receptor-1 were measured during the first and third trimester and 3 months postpartum. RESULTS: In diabetic women, levels of angiopoietin-2 were 26.5 ng/ml (12.1-47.7) (median and range) during the first trimester, 2.9 ng/ml (0.6-3.5) during the third trimester, and 0.5 ng/ml (0.3-0.7) 3 months postpartum, compared with 44.3 (38.3-61.9), 5.7 (3.1-8.4) and 0.9 (0.6-4.9) ng/ml, respectively, in non-diabetic women (P = 0.002 between groups). Levels of angiopoietin-1 and sVEGF receptor-1 did not differ between the groups. Postpartum hVEGF-A levels were lowest in women with progression of retinopathy. In logistic regression analyses, progression of retinopathy during pregnancy was not explained by the levels of the angiopoietic factors. CONCLUSIONS: The circulating levels of angiopoietic factors in pregnant diabetic women were either lower than (Ang-2) or similar to (Ang-1, hVEGF-A, VEGFR-1) those levels observed in non-diabetic pregnant women. The levels of angiopoietic factors measured here appear not to be connected with the progression of retinopathy during pregnancy.

Preliminary experience of combined peri- and retrobulbar block in surgery for penetrating eye injuries.

BACKGROUND AND OBJECTIVE: Regional anaesthesia has not been recommended as an anaesthetic method for penetrating eye injuries because it is suspected to aggravate the injury already present. After having successfully managed the treatment of a penetrating eye injury under combined peri- and retrobulbar block in an ASA IV patient, it was decided to evaluate this anaesthetic method further in the treatment of such emergency cases. METHODS: Twenty adult patients with penetrating eye injuries with a maximum wound length of 8 mm extending up to 4 mm posteriorly from the limbus were operated on under combined peri- and retrobulbar anaesthesia. Eighteen patients receiving general anaesthesia served as controls. RESULTS: The mean (range) volume injected for a satisfactory peribulbar retrobulbar block was 7.4 (6.5-8.0) mL, six patients needed an additional retrobulbar injection before surgery (2.9, range 2-4, mL). All patients receiving regional anaesthesia were satisfied with the anaesthetic method and the surgeons considered the surgical conditions as good. No problems relating to local anaesthesia were observed or reported by any of the patients. CONCLUSIONS: In the hands of an experienced anaesthesiologist and under certain conditions, regional anaesthesia appears to be suitable for adult patients having penetrating eye injuries.

Transscleral contact krypton laser cyclophotocoagulation for treatment of glaucoma in children and young adults.

PURPOSE: To evaluate the usefulness of the krypton laser for transscleral contact cyclophotocoagulation (CPC) in the treatment of glaucoma in young patients. DESIGN: Retrospective noncomparative interventional case series. PARTICIPANTS: Transscleral contact krypton laser CPC was performed in 27 glaucomatous eyes of 22 young patients (mean age, 10.5 +/- 5.6 years; range, 11 months-19.4 years). METHODS: The treatment was delivered by means of a fiberoptic probe with compression of the sclera by the probe. The power used was 300 to 500 W per application at the tip of the probe with an exposure time of 10 seconds. MAIN OUTCOME MEASURES: The primary outcome measure is a change in intraocular pressure (IOP). RESULTS: Of the patients who received CPC in both eyes, one eye was randomly chosen for statistical analysis. The mean overall follow-up time was 43.3 +/- 25.3 (median, 36.5; range, 1-82) months after the initial CPC. Preoperatively, the mean intraocular pressure was 35.0 +/- 7.9 mmHg (n = 22). After one or more CPCs, the mean IOP was decreased to 21.5 +/- 8.7 mmHg (n = 22) at 1 month (P < 0.001), to 23.4 +/- 8.6 mmHg (n = 18) at 3 months (P < 0.001), to 25.0 +/- 12.1 mmHg (n = 19) at 6 months (P < 0.01), to 22.1 +/- 9.1 mmHg (n = 16) at 1 year (P < 0.01), and to 22.6 +/- 10.3 (n = 11) at 2 years (P < 0.01). After one or more krypton CPCs, but no other glaucoma procedures, an IOP level of 8 to 21 mmHg or a decrease in IOP of more than 30% was obtained in 14 of 22 (64%) eyes at the last follow-up. No permanent hypotonia, phthisis bulbi, or devastating CPC-related complications were noted. CONCLUSIONS: Krypton laser CPC is a well-tolerated means of lowering IOP in young patients with glaucoma, but repeated treatments may be needed.

Grading choroidal neovascular membrane regression after strontium plaque radiotherapy; masked subjective evaluation vs planimetry.

PURPOSE: To analyze angiographic changes in choroidal neovascular membranes (CNVM) after strontium-plaque (90Sr) irradiation for exudative age-related macular degeneration (AMD) using masked measurement of the CNVM areas and a masked subjective comparison of CNVM size and leakage. METHODS: We studied the baseline, 3, 6, and 12-month angiograms of 19 eyes treated with 90Sr-plaque irradiation for exudative AMD. The area of CNVM-related hyperfluorescence was measured quantitatively, and the angiograms were subjectively evaluated by a masked grader. RESULTS: In 7 of the 19 eyes the CNVM-related hyperfluorescence was too scattered to be analyzed by planimetry but masked subjective grading correlated with the clinical response to irradiation. In the remaining 12 eyes, the CNVM decreased in size in 67% of the eyes and showed leakage in 67%. Planimetry and subjective assessment of the size and leakage of the CNVMs similarly reflected the regression after irradiation. CONCLUSIONS: CNVM size and leakage frequently diminish after 90Sr-plaque irradiation. Quantitative measurement of the CNVM areas, or a grading system based on masked subjective assessment, give similar results for evaluating these changes. Masked subjective grading can be used even in cases where the CNVM is too scattered to be outlined for planimetry.

Transscleral contact krypton laser cyclophotocoagulation for treatment of posttraumatic glaucoma.

PURPOSE: To evaluate the usefulness of the krypton laser for transscleral contact cyclophotocoagulation in the treatment of posttraumatic glaucoma. PATIENTS AND METHODS: A total of 18 eyes of 18 patients with therapy-resistant posttraumatic glaucoma treated with krypton laser cyclophotocoagulation from 1991 to 1996 were included in this review. The krypton laser was delivered by a fiberoptic probe with simultaneous compression of the sclera. The energy used was 3 to 5 J per application at the tip of the probe, with an exposure time of 10 seconds. The treatment covered 90 to 360 degrees of the ciliary body with approximately 10 applications per quadrant. RESULTS: With one or more cyclophotocoagulation treatments, the intraocular pressure decreased from the baseline mean (+/- standard deviation) of 32.6 +/- 12.8 mm Hg to 23.6 +/- 10.3 mm Hg (n = 17) at 1 month, to 21.8 +/- 7.5 mm Hg (n = 13) at 3 months, to 22.5 +/- 7.6 mm Hg (n = 13) at 6 months, and to 19.6 +/- 10.5 mm Hg (n = 18) at the last control visit (mean, 19.4 months; range, 3 weeks to 73 months) after cyclophotocoagulation but no other glaucoma procedure. At baseline, 17 (94%) of 18 patients were taking glaucoma medication, as were 15 (83%) of 18 patients at the last control visit. One (6%) case of phthisis occurred. CONCLUSIONS: Krypton laser cyclophotocoagulation is an effective and reasonably well tolerated means of lowering intraocular pressure in posttraumatic glaucoma. Because of the refractory nature of the disease, repeated treatments may be needed.

Retinal breaks before and after neodymium:YAG posterior capsulotomy.

PURPOSE: To determine the frequency of asymptomatic retinal breaks before and after neodymium:YAG (Nd:YAG) laser posterior capsulotomy. SETTING: Department of Ophthalmology, Helsinki University Central Hospital, Helsinki, Finland. METHODS: Of 350 consecutive patients referred for their first laser Nd:YAG posterior capsulotomy, 235 eligible eyes were enrolled and 220 eyes completed the study. A vitreoretinal surgeon looked for retinal breaks using binocular indirect ophthalmoscopy with scleral indentation. The eyes were examined 1 week before and 1 hour and 1 month after the posterior capsulotomy. The number, type, and location of retinal breaks were recorded. RESULTS: The median age of eligible patients who did not participate in the study was higher than that of enrolled patients (79.6 versus 74.4 years; P =.0005). The mean axial length, median time from cataract surgery, and the course of cataract surgery were comparable in both groups. Before the posterior capsulotomy, an untreated retinal break was diagnosed in 4 of the 235 eyes (1.7%; 95% confidence interval [CI] 0 to 4) scheduled for surgery and an undiagnosed retinal detachment was present in 2 additional eyes (0.9%; 95% CI 0 to 3). An asymptomatic retinal break was also present in 4 fellow eyes (1.7%, 95% CI 0 to 4). No new breaks developed during Nd:YAG posterior capsulotomy using a median total energy of 51 mJ (range 10 to 901 mJ) and a median number of 22 applications (range 4 to 341 applications) and resulting in an opening with a median largest diameter of 3.4 mm (range 2.0 to 4.6 mm). In 1 treated eye (0.4%; 95% CI 0 to 2), a new retinal break had developed by 1 month postoperatively. CONCLUSIONS: The observed 2.1% frequency of asymptomatic retinal breaks that had escaped the attention of the referring ophthalmologist or had developed by 1 month after Nd:YAG posterior capsulotomy can be contrasted with the 0.5% to 2.0% frequency of retinal detachment reported in the literature. However, it is not known which proportion of such asymptomatic breaks, if any, will progress to detachment after Nd:YAG laser posterior capsulotomy.

Corneal structure and sensitivity in type 1 diabetes mellitus.

PURPOSE: Corneal wound healing is impaired in diabetic cornea. The purpose of this study was to examine patients with type 1 diabetes mellitus for changes in corneal morphology and to correlate corneal sensitivity, subbasal nerve morphology, and degree of polyneuropathy with each other. METHODS: Forty-four eyes of 23 patients with diabetes and nine control eyes were included. Corneal sensitivity was tested with a Cochet-Bonnet esthesiometer (Luneau, Paris, France), and corneal morphology and epithelial and corneal thickness were determined by in vivo confocal microscopy. The density of subbasal nerves was evaluated by calculating the number of long subbasal nerve fiber bundles per confocal microscopic field. The degree of polyneuropathy was evaluated using the clinical part of the Michigan Neuropathy Screening Instrument (MNSI) classification, and retinopathy was evaluated using fundus photographs. RESULTS: A reduction of long nerve fiber bundles per image was noted to have occurred already in patients with mild to moderate neuropathy, but corneal mechanical sensitivity was reduced only in patients with severe neuropathy. Compared with control subjects the corneal thickness was increased in patients with diabetes without neuropathy. The epithelium of patients with diabetes with severe neuropathy was significantly thinner than that of patients with diabetes without neuropathy. CONCLUSIONS: Confocal microscopy appears to allow early detection of beginning neuropathy, because decreases in nerve fiber bundle counts precede impairment of corneal sensitivity. Apparently, the cornea becomes thicker in a relatively early stage of diabetes but does not further change with the degree of neuropathy. A reduction in neurotrophic stimuli in severe neuropathy may induce a thin epithelium that may lead to recurrent erosions.

Transforming growth factor beta induces urokinase receptor expression in cultured retinal pigment epithelial cells.

The effect of transforming growth factor-beta1 (TGF-beta1) and interferon-gamma (IFN-gamma) was studied on urokinase receptor (uPAR) expression of cultured human retinal pigment epithelial (RPE) cells. Human RPE cells were incubated with 1, 5 or 10 ng/ml of TGF-beta1 or with 10, 100 or 1,000 IU/ml of IFN-gamma to measure total cellular uPAR protein and released uPAR by enzyme immunoassay. uPAR at cell surface was measured by flow cytometric analysis at 8, 12, 24 and 48 h. uPAR mRNA levels were assayed by Northern blotting at 2, 6, 12 and 24 h. The increase in uPAR gene expression in RPE cells exposed to TGF-beta1 paralleled enhanced uPAR level at the cell surface and in conditioned medium. TGF-beta appeared to induce also membrane-bound uPA activity and the release of active plasminogen activator inhibitor-1, indicating that TGF-beta has the potential to regulate plasminogen activation at the RPE cell surface. The increase in uPAR gene expression by IFN-gamma did not seem to translate into the protein level. We conclude that TGF-beta regulates the pericellular proteolysis in RPE cells by increasing uPAR expression.

Visual function after strontium-90 plaque irradiation in patients with age-related subfoveal choroidal neovascularization.

PURPOSE: To report 2-year visual and angiographic results in eyes treated with strontium plaque irradiation for subfoveal choroidal neovascular membranes (CNVM) in age-related macular degeneration. METHODS: Twenty eyes with recent subfoveal CNVM were treated with local irradiation. The impact of the treatment on visual function was evaluated by visual acuity, contrast sensitivity and reading speed testing. RESULTS: At 12 months visual acuity had improved or remained the same in 9/ 20 eyes (45%). At 24 months visual acuity was stable in 5/18 eyes (28%). Eyes with signs of CNVM regression (13/18, 72%) lost a mean of 3.3 lines, but eyes with recurrent CNVM lost a mean of 5.1 lines of vision. The mean contrast sensitivity was better in the irradiated eyes than in the fellow eyes with late age-related macular degeneration at 24 months. Six of 17 irradiated eyes (35%) could read at least some words at 24 months. CONCLUSIONS: Visual function decreases in patients treated with strontium irradiation, but less in eyes showing regression of the CNVM than in eyes with further growth of the CNVM.

The use of confocal scanning laser tomography in the evaluation of retinal elevation in age-related macular degeneration.

OBJECTIVE: To evaluate the feasibility of using confocal scanning laser tomography in the analysis of macular topography in patients with subfoveal choroidal neovascularization associated with age-related macular degeneration (AMD) and to analyze quantitatively the changes in topography after local strontium-plaque radiation therapy. DESIGN: Prospective case series. PARTICIPANTS: A total of 16 eyes with subfoveal choroidal neovascular membranes (CNVM) treated with strontium-90 (90Sr)-plaque radiation therapy and 16 fellow eyes of 16 patients were examined. INTERVENTION: Confocal scanning laser analysis of macular surface topography before and after irradiation of the macula was performed. MAIN OUTCOME MEASURES: Parameters describing the height and volume of the retinal elevation in the macula were measured. RESULTS: The maximum height of the macular lesion at baseline was 0.25 mm (standard deviation [SD], 0.12 mm) in eyes showing regression of the CNVM during follow-up and 0.34 mm (SD, 0.19 mm) in eyes showing continued growth of the CNVM. During follow-up, a mean decrease in the maximum height of the macular lesion ranging from 0.03 to 0.10 mm occurred in eyes with regression of the CNVM, whereas the mean maximum height increased by 0.07 to 0.15 mm during follow-up visits in eyes with continued growth of the CNVM. All parameters describing the mean height and volume of the lesion also decreased significantly in patients showing angiographic regression, whereas they increased or remained unchanged in patients with continuous growth of the CNVM despite irradiation. The corresponding parameters also were higher in fellow eyes with untreated CNVM than in eyes without exudative AMD. CONCLUSIONS: Confocal scanning laser tomography can be used to monitor the amount of the change in neurosensory detachment in AMD. The parameters obtained by confocal scanning laser tomography correlate with CNVM perfusion after 90Sr-plaque radiation therapy. This technology is a useful tool for objective evaluation of morphologic change after institution of new therapeutic methods for the treatment of AMD.

Biodegradable tube implants in experimental glaucoma surgery in the rabbit.

Although ocular drainage implants are manufactured from biocombatible materials to reduce foreign-body reaction, the formation of excessive scar tissue around the implant is a common cause for implant failure. In this study, the suitability of poly(D, L-lactide-co-glycolide) copolymer, impregnated with an antiproliferative agent retinoic acid, was evaluated as a material for biodegradable tubular implants, as well as the duration and magnitude of the intraocular pressure reduction obtained with the prototype implant. Subconjunctivally placed retinoid-impregnated polymer particles caused a milder inflammatory reaction than plain polymer, and the layer of connective tissue around the material was thinner after the follow-up period of 60 d. In the anterior chamber, the inflammatory response elicited by the material was milder than subconjunctivally. The plain polymer caused a transiently stronger reaction than the retinoid-impregnated polymer, but after 60 d no difference was evident between the two materials. In all operated eyes with the tubular implant, the intraocular pressure was statistically significantly lower (p<0.05) than in control eyes for 9 wk after the operation. The intraocular pressure of the eyes with the retinoid-impregnated implant was statistically significantly lower (p<0.05) than in eyes with a plain polymer implant for up to 7 wk post-operatively. However, the use of retinoid did not prolong the effective functioning time of the implants.

Strontium plaque irradiation of subfoveal neovascular membranes in age-related macular degeneration.

PURPOSE: To determine the effect of focal strontium-90 plaque radiotherapy on subfoveal choroidal neovascularization in patients with age-related macular degeneration. METHODS: Twenty patients with age-related macular degeneration, presenting with a recent subfoveal neovascular membrane, were treated with local episcleral radiotherapy using a strontium-90 applicator. The applicator was applied to the sclera under the macular region and held there tightly for 54 min to obtain a dose of 15 Gy at a depth of 1.75 mm. The main parameters evaluated at follow-up after 3, 6 and 12 months were visual acuity and changes in fluorescein angiography. Twelve untreated patients with the same criteria were followed as controls. RESULTS: Early effects of radiation could be seen at 3 months, but became more obvious after follow-up for 6 and 12 months. At 6 months, regression of the choroidal neovascularization was detected in 14/19 patients (74%) as a decrease in the size of the lesion or as diminished leakage in late-phase fluorescein angiography. Likewise, in 14/19 patients (74%) at 12 months the neovascular membrane was partially or totally occluded. In all patients showing regression of the choroidal neovascular membrane, the neurosensory detachment had also dried. Visual acuity was unchanged (within 1 line) or improved in 11/20 (55%) and 9/20 (45%) treated patients after 6 and 12 months, respectively. In the controls, the choroidal neovascularization had increased in size in 9/12 patients (75%) at the last follow-up (mean 12.0 months). Visual acuity was unchanged in 3/12 patients (25%). CONCLUSION: Local low-energy beta irradiation with a strontium-90 applicator can induce regression of choroidal neovascularization. The effect of irradiation is seen as a decrease in the size of the choroidal neovascular membrane and disappearance of the neurosensory detachment and exudates.

Correlation between Octopus perimetry and fluorescein angiography after strontium-90 plaque brachytherapy for subfoveal exudative age related macular degeneration.

AIM: To evaluate the correlation between the central visual field and changes in fluorescein angiography and fundus photography in patients treated with strontium plaque radiotherapy for subfoveal exudative age related macular degeneration (AMD). METHODS: Octopus program 34 automated static perimetry, fluorescein angiography, and colour fundus photography were performed on 19 patients at baseline and at 12 months after strontium-90 plaque therapy. A schematic picture outlining the areas of hyperfluorescent neovascular membranes and subretinal blood was drawn of a projected 30 degrees fundus fluorescein angiogram. This drawing was superimposed on the size adjusted Octopus visual field. The changes in retinal sensitivity were calculated and related to angiographic changes. RESULTS: Three of the 19 patients had a reliability factor (RF) > 15% and were excluded from further analysis. In the remaining 16 patients the mean defect (MD) and loss variance (LV) values remained unchanged in patients showing regression of the choroidal neovascular membrane (CNVM) to irradiation at 12 months. MD was 7.7 (SD 1.7) at baseline and 7.6 (1.9) at 12 months (p = 0.86), and LV was 32.6 (13.9) at baseline and 32.4 (15.7) at 12 months (p = 0.94). However, in patients with progression of the CNVM at 12 months, both the MD and LV increased significantly during the 12 month follow up (MD from 7.3 (2.9) to 13.1 (3.6) (p = 0.05) and LV from 31.0 (22.9) to 71.8 (24.1) (p = 0.017)). When comparing the mean retinal sensitivity in the area of the primary CNVM (including classic, occult, and haemorrhagic components), the results were analogous: in patients with a regression of the CNVM after irradiation the mean sensitivity remained almost unchanged. It was 10.3 (6.4) dB at baseline and 9.4 (7.3) dB at 12 months (p = 0.58). In five out of 11 patients (45%) with regression of the CNVM, the mean retinal sensitivity even improved by 2.0-5.0 dB in the area of the original lesion during follow up. Instead, in patients showing progression of the CNVM at 12 months, there was a significant loss in mean retinal sensitivity--from 9.9 (4.6) dB at baseline to 1.0 (1.1) dB at 12 months (p = 0.019). The mean retinal sensitivity in the area of the irradiated but clinically normal retina during follow up was not significantly altered (21.5 dB at baseline, 19.7 dB at 12 months (p = 0.10)). CONCLUSIONS: Regression of subfoveal choroidal membranes in AMD after focal strontium irradiation is connected with stabilisation or even improvement of retinal sensitivity in central visual field measured by automated perimetry. Strontium plaque irradiation does not change the sensitivity in clinically normal paramacular retina during a 12 month follow up.

The effect of pregnancy on mild diabetic retinopathy.

PURPOSE: To study microaneurysm (MA) formation and disappearance rates during pregnancy and postpartum in diabetic women with mild diabetic retinopathy. METHODS: Red-free photographs were taken at the 12th, 24th and 32nd-36th weeks of pregnancy and 3 and 6 months postpartum from 21 type 1 diabetics with mild diabetic retinopathy. In a subset of 13 patients follow-up was continued until 1 year after pregnancy. Fundus photographs were analysed using a computer-assisted fundus lesion localization system. RESULTS: In the whole material the total MA count was 3.1 +/- 3.6 (mean +/- SD) at the 12th week, 3.4 +/- 3.1 at the 24th week, 4.1 +/- 4.9 at the 32nd-36th week, 5.4 +/- 6.2 at 3 months postpartum and 5.2 +/- 5.8 at 6 months postpartum. We found that MA count increased during pregnancy, but it was highest 3 months postpartum. Both the rate of MA formation and the rate of MA disappearance increased during pregnancy, with the disappearance rate exceeding the formation rate 6 months postpartum. In patients having mean HbA1c levels below the median value of 6.38 mmol/l there was a flare-up of MAs during pregnancy, levelling by 3 months postpartum. Patients with a higher than the median (0.76 mmol/l) decrease in HbA1c level compared to pre-pregnancy HbA1c also developed more MAs during the course of pregnancy. CONCLUSIONS: These data suggest that there is continuous turnover of MAs during pregnancy. MA count increases during pregnancy but the MA count was highest 3 months postpartum, after which the formation rate started to decline. Temporary aggravation of mild retinopathy occurs in diabetic patients after normalization of blood glucose levels.

Contrast sensitivity in diabetic pregnancy.

PURPOSE: To evaluate the correlation between the changes in contrast sensitivity and retinopathy throughout pregnancy in diabetic women with mild background diabetic retinopathy. METHODS: Contrast sensitivity (Vistech 6500 Contrast Test System) was measured in 22 type I diabetic women with mild background retinopathy [0-16 microaneurysms (MAs)/eye and occasional small intraretinal hemorrhages] and 10 healthy pregnant women at the 12th and 32nd weeks of pregnancy and 3 months after delivery. Red-free fundus photography was also performed at all visits. RESULTS: Throughout pregnancy contrast sensitivity was lower in the diabetics than in the controls at 1.5, 3.0, and 6.0 cycles per degree (cpd). During the course of pregnancy, contrast sensitivity decreased at 1.5 and 6.0 cpd in patients with more than five new MAs compared to those with fewer than five new MAs during pregnancy. Likewise, contrast sensitivity decreased at 6 cpd in patients with an increase in MA count during pregnancy and at 6 and 12 cpd in patients with a baseline MA count of two or more MAs. CONCLUSIONS: Contrast sensitivity, especially at low to mid-range spatial frequencies, is decreased in diabetic women with mild retinopathy. Even small changes in retinopathy are reflected in a decrease in contrast sensitivity during and after pregnancy. Thus, contrast sensitivity seems to be a sensitive indicator of changes in minimal background retinopathy.

Early versus late staining of microaneurysms in fluorescein angiography.

PURPOSE: To analyze the appearance and disappearance of microaneurysms in different phases of fluorescein angiography. METHODS: Three fluorescein angiograms were taken at 13-month intervals during a 26-month follow-up period from 13 patients with type I diabetes and mild background retinopathy. Two frames of the angiogram were analyzed: one from the transit phase and the other from the late phase of the angiogram. Individual microaneurysms were identified and localized from each frame using a computerized system for retrieval of the coordinates for each microaneurysm. Microaneurysms identified by their location then were analyzed in relation to the phase of the angiogram in which they were visualized and their disappearance during follow-up study. RESULTS: Thirty-three percent of the microaneurysms were visualized only in the early phase, 31% in only the late phase, and 36% in both phases of the fluorescein angiogram. The microaneurysms frequently changed their phase of appearance in the angiogram during follow-up study. CONCLUSION: During the 26-month follow-up period, between 55% and 80% of the microaneurysms present at baseline disappeared. The phase of the baseline angiogram in which the microaneurysms were visualized did not determine their disappearance rate.