Visual field loss in HIV-positive patients without infectious retinopathy

Sociodemographic predictors associated with the spectrum of non-opportunist neuroretinal disease of non-infectious etiology in patients with HIV/AIDS: A scoping review

BACKGROUND

Non-infectious retinal disease, even in the HAART era, continues to be one of the most common diagnoses in patients with HIV, with prevalences of up to 27% of cases. This study aims to characterize the association between demographic variables and their role. As a risk factor for the development of non-opportunistic non-infectious retinal disease in patients with HIV/AIDS.

METHODS

An integrative review of the literature was carried out according to Arksey O'Malley's approach, based on the PICO methodology and following the PRISMA recommendations; An exhaustive search was carried out in databases of articles that were filtered using established criteria, with their extraction and analysis carried out qualitatively.

RESULTS

Ocular manifestations from any cause develop from 35 years of age in patients with HIV/AIDS, with the highest risk for age-related macular degeneration over the fourth decade of life and for the development of neuroretinal disorder on the fifth decade of life; some studies report a slight tendency to diagnose macular degeneration in women and those who acquired AIDS through sexual contact; data contrasted with increased risk for diagnosing neuroretinal disorder in homosexual men who also use intravenous drugs, possibly due to oversampling in studies; non-Hispanic whites and African Americans were the races most commonly affected by neuroretinal disease; the means between the 11.3-14.5 years elapsed since the HIV diagnosis were more frequently associated with cognitive impairment and both in those with high or low CD4 counts, and in patients with high or low viral loads, neuroretinal disease without Statistically significant differences. Adherence and early initiation of HAART had a modest impact on the development of neuroretinal disease.

DISCUSSION

Even in the HAART era, non-infectious neuroretinal disease and cytomegalovirus retinitis remain the most frequent ocular diagnoses, however, different studies argue an increase in age-related non-infectious retinal diseases in patients with HIV, theories that are may explain by the increase in life expectancy, the metabolic effects of HAART itself or the generalized pro-inflammatory state in this group of patients, it is essential to recognize this new diagnostic challenge in order to direct preventive efforts through the use of cost-effective sociodemographic risk predictors towards that technological tools for diagnosis and treatment can be targeted.

CONCLUSIONS

HIV/AIDS patients who present at the ophthalmological consultation with the suggested sociodemographic predictors have a high risk of visual impairment due to non-infectious retinopathy, therefore prevention, diagnosis and treatment efforts directed at these diseases should be increased.

Sociodemographic predictors associated with the spectrum of non-opportunist neuroretinal disease of non-infectious etiology in patients with HIV/AIDS: a scoping review

BACKGROUND

Non-infectious retinal disease, even in the HAART era, continues to be one of the most common diagnoses in patients with HIV, with prevalences of up to 27% of cases. This study aims to characterize the association between demographic variables and their role. as a risk factor for the development of non-opportunistic non-infectious retinal disease in patients with HIV/AIDS METHODS: An integrative review of the literature was carried out according to Arksey O'Malley's approach, based on the PICO methodology and following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) recommendations; An exhaustive search was carried out in databases of articles that were filtered using established criteria, with their extraction and analysis carried out qualitatively.

RESULTS

Ocular manifestations from any cause develop from 35 years of age in patients with HIV/AIDS, with the highest risk for age-related macular degeneration over the fourth decade of life and for the development of neuroretinal disorder on the fifth decade of life; some studies report a slight tendency to diagnose macular degeneration in women and those who acquired AIDS through sexual contact; data contrasted with increased risk for diagnosing neuroretinal disorder in homosexual men who also use intravenous drugs, possibly due to oversampling in studies; non-Hispanic whites and African Americans were the races most commonly affected by neuroretinal disease; the means between the 11.3 to 14.5 years elapsed since the HIV diagnosis were more frequently associated with cognitive impairment and both in those with high or low CD4 counts, and in patients with high or low viral loads, neuroretinal disease without Statistically significant differences. Adherence and early initiation of HAART had a modest impact on the development of neuroretinal disease.

DISCUSSION

Even in the HAART era, non-infectious neuroretinal disease and cytomegalovirus retinitis remain the most frequent ocular diagnoses, however, different studies argue an increase in age-related non-infectious retinal diseases in patients with HIV, theories that are may explain by the increase in life expectancy, the metabolic effects of HAART itself or the generalized pro-inflammatory state in this group of patients, it is essential to recognize this new diagnostic challenge in order to direct preventive efforts through the use of cost-effective sociodemographic risk predictors towards that technological tools for diagnosis and treatment can be targeted.

CONCLUSIONS

HIV/AIDS patients who present at the ophthalmological consultation with the suggested sociodemographic predictors have a high risk of visual impairment due to non-infectious retinopathy, therefore prevention, diagnosis and treatment efforts directed at these diseases should be increased.

[Importance of perimetric differential diagnostics in patients with primary open-angle glaucoma]

Functional deficits in glaucomatous optic neuropathy are, apart from other disturbances in the visual field, typically detected with achromatic perimetry as a well accepted gold standard. With the development of new perimetric devices and strategies (e.g. short wave perimetry, frequency doubling perimetry and flicker perimetry) individually different patterns of scotomas in the different perimetric devices could be recognized. The reasons for this could be a different sensitivity reaction of the ganglion cell subpopulations to an increased intraocular pressure as well as an influence of the underlying systemic diseases. To obtain a differentiated detection of the functional loss in the visual field in glaucoma, the use of different perimetric methods seems to be reasonable and helpful.

Human immunodeficiency virus and its effects on the visual system

During the first 15 years of the AIDS epidemic patients experienced a high incidence of blindness due to cytomegalovirus (CMV) retinitis and other severe ocular opportunistic infections. Highly active anti-retroviral therapy, introduced in 1996, dramatically decreased the incidence of CMV retinitis. Though CMV retinitis still causes 40% of vision loss in AIDS patients, other conditions such as immune reconstitution uveitis, cataracts, and a significant othercategory -which most investigators believe is directly due to HIV - comprise the majority of cases. HIV causes vascular abnormalities of the conjunctiva and retina in the majority of AIDS patients, as well as retinitis, anterior and posterior uveitis and vasculitis. HIV frequently causes an optic neuropathy and is responsible for the majority of eye movement disorders among HIV patients. Physicians need to be aware that these problems may be the initial manifestation of HIV infections or a sign of highly active anti-retroviral therapy (HAART) failure. Therefore, patients with identifiable risk factors for AIDS who present with ophthalmologic conditions of unknown etiology should be considered for HIV testing. Finally, anti-retroviral therapy has been reported to cause asymptomatic deposits as well as degenerative conditions of both the anterior and posterior segments of the eye.

Relationship between retinal nerve fiber layer thickness and driving ability in patients with human immunodeficiency virus infection

BACKGROUND

The aim of this work is to study the possible association between retinal nerve fiber layer (NFL) thickness and driving ability.

METHODS

Thirty-eight drivers including 22 HIV-positive (HIV+) and 16 age-matched HIV-negative controls participants underwent a full ophthalmologic evaluation, including assessment of retinal NFL thickness. In the undilated state with standard optical correction and under standard illumination they also completed a computer-based, wide field-of-view driving simulation in which they were to obey traffic laws, engage in crash avoidance, and pass slower automobiles. Crashes, speeding and traffic light tickets, and off-road excursions contributed to a weighted score of driving errors.

RESULTS

HIV-seropositive participants had a significantly higher weighted error score than control participants (18.4 [9.2] vs. 11.1 [4.5], p = 0.006). NFL thickness was significantly correlated with driving errors (r = -0.51, p = 0.025); there was a trend for participants with a CD4 nadir <100 to have more errors than those with a nadir >100 (29.7 [13.2] vs. 19.3 [8.4], p = 0.056). The highest number of driving errors occurred in individuals with both CD4 <100 and NFL thickness <80.

CONCLUSIONS

Driving ability may be impacted by reductions in retinal nerve fiber layer thickness. Physicians should consider the potential impact that more complex ophthalmologic conditions in HIV-infected patients may have on driving performance.

Pattern recognition can detect subtle field defects in eyes of HIV individuals without retinitis under HAART

Objectives

To use machine learning classifiers (MLCs) to seek differences in visual fields (VFs) between normal eyes and eyes of HIV+ patients; to find the effect of immunodeficiency on VFs and to compare the effectiveness of MLCs to commonly-used Statpac global indices in analyzing standard automated perimetry (SAP).

Methods

The high CD4 group consisted of 70 eyes of 39 HIV-positive patients with good immune status (CD4 counts were never <100/ml). The low CD4 group had 59 eyes of 38 HIV-positive patients with CD4 cell counts <100/ml at some period of time lasting for at least 6 months. The normal group consisted of 61 eyes of 52 HIV-negative individuals. We used a Humphrey Visual Field Analyzer, SAP full threshold program 24-2, and routine settings for evaluating VFs. We trained and tested support vector machine (SVM) machine learning classifiers to distinguish fields from normal subjects and high and CD4 groups separately. Receiver operating characteristic (ROC) curves measured the discrimination of each classifier, and areas under ROC were statistically compared.

Results

Low CD4 HIV patients: with SVM, the AUROC was 0.790 ± 0.042. SVM and MD each significantly differed from chance decision, with p < .00005. High CD4 HIV patients: the SVM AUROC of 0.664 ± 0.047 and MD were each significantly better than chance (p = .041, p = .05 respectively).

Conclusions

Eyes from both low and high CD4 HIV+ patients have VFs defects indicating retinal damage. Generalized learning classifier, SVM, and a Statpac classifier, MD, are effective at detecting HIV eyes that have field defects, even when these defects are subtle.

Structural and functional assessment in HIV-infected patients using optical coherence tomography and frequency-doubling technology perimetry

PURPOSE

To assess retinal nerve fiber layer (RNFL) and macular thickness using optical coherence tomography (OCT) on HIV-infected patients without ocular manifestations and to correlate these findings with frequency-doubling technology perimetry (FDT).

DESIGN

Cross-sectional study.

METHODS

setting: Single center. study population: Seventy-three patients (146 eyes) with clinically normal examination classified in 3 groups: group A, HIV-infected patients with CD4 count <100 cells/mm(3) for at least 6 months; group B, HIV-infected patients with CD4 count >100 cells/mm(3) since diagnosis; and group C, HIV-negative control subjects. observation procedures: Fast RNFL and fast macula scan strategies on Stratus OCT and Humphrey Matrix 24-2 full-threshold program. main outcome measures: OCT RNFL and macular thicknesses and FDT indices (mean deviation [MD], pattern standard deviation [PSD], and glaucoma hemifield test [GHT]).

RESULTS

Group A had a significantly thinner average RNFL, temporal outer macula, and inferior outer macula thicknesses when compared to groups B and C (P < .05). Statistically significant differences were observed in the FDT MD between groups A and C (P = .034) and in PSD in group A compared to groups B and C (P = .011). Eyes of HIV patients with GHT and PSD results outside normal confidence limits had thinner average RNFL thickness measures than eyes with results within normal limits in the same group of patients (P < .05).

CONCLUSIONS

HIV-infected patients with low CD4 count have a significant RNFL and macular thinning. Functional loss detected by FDT is related to RNFL thinning in HIV-infected patients.

[Functional glaucoma diagnosis]

Achromatic perimetry is the gold standard in glaucoma diagnosis for detecting functional defects from glaucomatous optic neuropathy. Because achromatic perimetry is only able to detect scotomas after loss of up to 30-40% of retinal ganglion cells, early diagnosis using this method is rarely possible. Therefore, a lot of new perimetric procedures have been developed in recent years to detect new scotomas at a very early stage. This review summarizes the theoretical background of retinal ganglion cells in order to better understand the theoretical approaches of new perimetric methods. In addition, the most important commercial perimetric devices currently available are presented.

Multifocal electroretinography in HIV-positive patients without infectious retinitis

PURPOSE

To evaluate early changes in the central retinal response in human immunodeficiency virus (HIV)-positive patients without infectious retinitis using multifocal electroretinography (mfERG).

DESIGN

Case control study.

METHODS

We evaluated three cohorts: HIV-negative controls and two groups of HIV-positive patients separated according to their nadir CD4 counts (>or= 100 cells/mm(3) and < 100 cells/mm(3) for a minimum of six months). mfERG first-order kernels (FOKs) and second-order kernels (SOKs) were analyzed separately by areas of rings, quadrants, and individual hexagons for each cohort.

RESULTS

Of 103 hexagon locations of FOK results, there were no significant differences in amplitudes of P1 and N1 across the groups (.05 < P < .50), although there was a trend for an overall reduction in the amplitudes. Similarly, latency N1 did not differ (.28 < P < .95). There were significantly delayed latencies of P1 between cohorts across 103 hexagons in both kernels. SOK results also showed significant delay in latencies of P1 and a trend of reduced P1 amplitudes across studied locations among cohorts (.24 < P < .08).

CONCLUSIONS

The results demonstrate widespread delay in latency in HIV-positive patients, especially in those with prolonged low (below 100 cells/mm(3)) CD4 nadir counts. These findings suggest early diffuse dysfunction of the inner retina results from severe HIV disease even in the HAART era.

Vision function in HIV-infected individuals without retinitis: report of the Studies of Ocular Complications of AIDS Research Group

PURPOSE

To evaluate the prevalence and risk factors for vision loss in patients with clinical or immunologic AIDS without infectious retinitis.

DESIGN

A prospective, multicenter cohort study of patients with AIDS.

METHODS

One thousand three hundred and fifty-one patients (2,671 eyes) at 19 clinical trials centers diagnosed with AIDS but without major ocular complications of HIV. Standardized measurements of visual acuity, automated perimetry, and contrast sensitivity were analyzed and correlated with measurements of patients' health and medical data relating to HIV infection. We evaluated correlations between vision function testing and HIV-related risk factors and medical testing.

RESULTS

There were significant (P<.05) associations between measures of decreasing vision function and indices of increasing disease severity, including Karnofsky score and hemoglobin. A significant relationship was seen between low-contrast sensitivity and decreasing levels of CD4+ T-cell count. Three percent of eyes had a visual acuity worse than 20/40 Snellen equivalents, which was significantly associated with a history of opportunistic infections and low Karnofsky score. When compared with external groups with normal vision, 39% of eyes had abnormal mean deviation on automated perimetry, 33% had abnormal pattern standard deviation, and 12% of eyes had low contrast sensitivity.

CONCLUSIONS

This study confirms that visual dysfunction is common in patients with AIDS but without retinitis. The most prevalent visual dysfunction is loss of visual field; nearly 40% of patients have some abnormal visual field. There is an association between general disease severity and less access to care and vision loss. The pathophysiology of this vision loss is unknown but is consistent with retinovascular disease or optic nerve disease.

Objective analysis of retinal function in HIV-positive children without retinitis using optical coherence tomography

PURPOSE

To assess the retinal nerve fiber layer thickness in children with human immunodeficiency virus disease without cytomegalovirus retinitis or visual symptoms.

METHODS

Thirty-eight eyes of 19 human immunodeficiency virus-positive children (group A) with visual acuity of 20/20 or better, normal color vision testing and no ophthalmoscopically detectable disorders were prospectively examined. All subjects of group A had no history of cytomegalovirus retinitis and CD4 counts consistently above 100. Patients in group B (40 eyes of 21 patients) were human immunodeficiency virus-negative age-matched control subjects. Thickness of retinal nerve fiber layer along a 3.4-mm-diameter circle centered on the optic nerve head was evaluated using third-generation optical coherence tomography. CD8 T-lymphocyte count, presence of systemic infection, hemoglobin, hematocrit and serum beta-microglobulin levels were also recorded.

RESULTS

The mean overall retinal nerve fiber layer thickness in groups A and B were 89.2 +/- 24.01 microm and 102.82 +/- 29.168 microm (SD) respectively. The difference was considered extremely significant (P < 0.0001). Group A had significantly thinner average nerve fiber layer in temporal, nasal, superior and inferior retinal areas.

CONCLUSIONS

Significant retinal nerve fiber layer thinning occurs in human immunodeficiency virus-positive children with no visual impairment or ophthalmologic evidence or retinitis.

Effect of Cytomegalovirus Retinitis on the Risk of Visual Acuity Loss among Patients with AIDS

PURPOSE

To describe the prevalence and incidence of reduced visual acuity in eyes of patients with AIDS and without cytomegalovirus (CMV) retinitis at enrollment and estimate the proportion of incident vision loss attributable to new-onset CMV retinitis in this cohort.

DESIGN

Multicenter prospective observational study.

PARTICIPANTS

Three thousand fourteen eyes of 1507 patients with AIDS and without CMV retinitis at enrollment.

METHODS

Medical history, ophthalmologic examination, and laboratory testing collected at enrollment and at follow-up visits every 6 months thereafter.

MAIN OUTCOME MEASURES

Loss of visual acuity across the < or =20/50 and < or =20/200 thresholds and doubling of the visual angle; potential causes of this vision loss.

RESULTS

For eyes of patients without CMV retinitis at enrollment, the proportions with best-corrected visual acuity of < or =20/50 and of < or =20/200 were 3.9% and 1.8%, respectively. The incidence rates of vision loss to < or =20/50, < or =20/200, and to a doubling of the visual angle were 1.5/100 eye-year (EY), 0.8/100 EY, and 2.1/100 EY, respectively. Approximately 40% of the incident vision loss was attributable to CMV retinitis diagnosed during the follow-up period, and approximately 25% was attributable to cataract.

CONCLUSIONS

Although the development of CMV retinitis was the most common reason for visual acuity loss in eyes of our patients with AIDS, it accounted for less than half of the vision loss in our population (approximately 40%). Newly diagnosed cataract during the follow-up period accounted for a substantial amount of incident vision loss as well.

Longitudinal study of the ocular complications of AIDS: 2. Ocular examination results at enrollment

OBJECTIVE

To report the clinical features on eye examination of patients with AIDS in the era of highly active antiretroviral therapy (HAART).

DESIGN

Cohort study.

PARTICIPANTS

Patients with AIDS, age > or = 13 years.

METHODS

Ophthalmologic examination, contrast sensitivity, visual fields, and laboratory testing at enrollment.

MAIN OUTCOME MEASURES

Eye examination findings at enrollment.

RESULTS

As of March 31, 2003, 1632 participants with AIDS were enrolled. Evidence of intraocular inflammation was substantially more common among patients with cytomegalovirus (CMV) retinitis or other major ocular complications than among those without, as were the complications of infection and inflammation, including cataracts, pseudophakia, macular edema, and epiretinal membrane. Among patients with CMV retinitis, macular edema and epiretinal membrane formation were most common among patients with long-standing retinitis and immune recovery. Patients with newly diagnosed retinitis had eye examination findings similar to those reported in the pre-HAART era. Visual impairment (<20/40) in the better-seeing eye was present in 9.2% of patients with CMV retinitis, 41.4% of patients with other major ocular complications (primarily ocular opportunistic infections), and only 0.6% of patients with no major ocular complication (P<.0001). Although patients without major ocular complications generally had good visual acuity, approximately 9.8% of eyes and 6.6% of participants had contrast sensitivity loss sufficient to impair reading speed.

CONCLUSIONS

In the HAART era, CMV retinitis and other ocular opportunistic infections are associated with intraocular inflammation, structural ocular complications, and visual impairment. Patients with newly diagnosed CMV retinitis have eye examination findings similar to those seen in the pre-HAART era.

ASSESSMENT OF RETINAL FUNCTION IN PATIENTS WITH HIV WITHOUT INFECTIOUS RETINITIS BY MULTIFOCAL ELECTRORETINOGRAM AND AUTOMATED PERIMETRY

PURPOSE

To determine if multifocal electroretinogram (mfERG) testing shows abnormalities that correspond to perimetric defects in HIV positive patients without infectious retinitis.

METHODS

We studied three groups of patients: HIV negative controls, HIV high CD4 nadir patients (lowest CD4 T cell count is over 100) and low CD4 nadir patients (below 100 for over 6 months). Twenty-six HIV positive eyes and 16 HIV negative control eyes were studied by mfERG. A subset of 10 eyes also underwent computerized perimetry for comparison. We analyzed mfERG by hexagons as well as by quadrants and rings.

RESULTS

Of 103 hexagon locations there was no significant difference in the amplitudes P1 and N1 (nV/degree) between the three studied groups (p>0.05), similarly, the latencies were not different (p>0.05). All eyes with significant visual field defects at the 0.01 and 0.005 level (Humphrey pattern deviation; 24-2) were compared to mfERG amplitudes and latencies at those locations-there were no corresponding defects in mfERG data (p>0.2).

CONCLUSION

In the era of HAART there are still demonstrable visual field defects and other evidence of damage to the retinal nerve fiber layer in HIV patients. Our mfERG studies show that the damage appears to affect the inner retina, the outer retina is spared. Further studies of inner retinal structure and function are indicated to elucidate this process.

Objective analysis of retinal damage in HIV-positive patients in the HAART era using OCT

PURPOSE

To assess retinal nerve fiber layer (RNFL) thickness in patients with human immunodeficiency virus (HIV) disease without cytomegalovirus retinitis (CMV).

DESIGN

A case-control study.

METHODS

The study included 113 eyes of 65 patients in one center. Thickness of RNFL along a 3.4-mm-diameter circle centered on the optic nerve head was evaluated using third-generation optical coherence tomography. Patients in group A (39 eyes of 22 patients) were human immunodeficiency virus-negative control subjects. Group B (36 eyes of 18 patients) was composed of HIV patients with no history of CMV retinitis and CD4 counts consistently above 100. Group C (38 eyes of 25 patients) comprised HIV patients with no history of CMV retinitis but a history of CD4 count less than 100 at some point lasting for at least 6 months.

RESULTS

The average RNFL thicknesses in groups A, B, and C were 103.33 +/- 8.50 microm, 103.30 +/- 9.28 microm, and 90.10 +/- 12.50 microm, respectively. Group C had significantly thinner overall RNFL than either of the groups A and B (Tukey-Kramer). This difference was most prominent in temporal, superior, and inferior retinal areas. No difference was in nasal retinal area, nor between groups A and B in any of the areas.

CONCLUSIONS

Significant RNFL thinning occurs in HIV patients without CMV retinitis and with low CD4 counts compared with the same subgroup of patients with CD4 count increased to above 100 and HIV-negative control subjects. Third-generation OCT may be useful in diagnosis of early subclinical HIV-associated visual functional loss.

Beyond visual acuity: new and complementary tests of visual function

Visual acuity is an essential component of the routine ophthalmic examination and the most common measure of visual function. There is increasing recognition, however, of the need to evaluate visual function beyond the limited extent afforded by visual acuity. The primary objective of this article is to introduce a variety of new and lesser-used techniques for measuring visual function that complement visual acuity assessment, each of which has been shown to detect visual dysfunction in patients with normal visual acuity.

Short wavelength automated perimetry

Short Wavelength Automated Perimetry (SWAP) utilizes a blue stimulus to preferentially stimulate the blue cones and a high luminance yellow background to adapt the green and red cones and to saturate, simultaneously, the activity of the rods. This review describes the theoretical aspects of SWAP, highlights current limitations associated with the technique and discusses potential clinical applications. Compared to white-on-white (W-W) perimetry, SWAP is limited clinically by: greater variability associated with the estimation of threshold, ocular media absorption, increased examination duration and an additional learning effect. Comparative studies of SWAP and W-W perimetry have generally been undertaken on small cohorts of patients. The conclusions are frequently unconvincing due to limitations for SWAP in the delineation of abnormality and of progressive field loss. SWAP is almost certainly able to identify glaucomatous visual field loss in advance of that by W-W perimetry although the incidence of progressive field loss is similar between the two techniques. Increasing evidence suggests that functional abnormality with SWAP is preceded by structural abnormality of the optic nerve head and/or the retinal nerve fibre layer. SWAP appears to be beneficial in the detection of diabetic macular oedema and possibly in some neuro-ophthalmic disorders.

Latent ocular deviations in patients with advanced AIDS

The purpose of this study is to determine horizontal latent ocular deviations in patients with advanced AIDS (CD4+ count <0.050 x 10(9)/l) and to compare with normal values by means of the von Graefe technique. Twenty patients aged between 17 and 44 years with AIDS and aged-matched control groups were submitted to study. The AC/A ratio was also measured in both groups using the Gradient test. The AIDS patients showed a horizontal latent deviation value of 0.28+/-1.07delta exo at near (40 cm.) and 2.12+/-1.37delta eso at distance (6 m). The AC/A ratio obtained was 2.03+/-0.65. Statistically significant differences were obtained in relation to aged-matched control group at near and at distance (p<0.01). The horizontal latent ocular deviation at near and at distance in advanced AIDS patients showed lower values than the expected. The AC/A relationship also was lower. The results obtained in this study indicate that AIDS patients suffer a divergence insufficiency, which could add to other visual complaints such as blurred vision, photophobia, nyctalopia and reading difficulty.

Retinal nerve fiber layer evaluation in human immunodeficiency virus-positive patients

PURPOSE

To determine the effect of human immunodeficiency virus (HIV) infection on topographic measures of the optic disk and the retinal nerve fiber layer.

METHODS

A cross-sectional study at the Acquired Immunodeficiency Syndrome (AIDS) Ocular Research Unit at the University of California, San Diego. Retinal nerve fiber layer thickness at the optic nerve head was evaluated using the Heidelberg Retinal Tomograph, a confocal scanning laser tomograph in 38 HIV-positive and 24 age-matched HIV-negative subjects.

RESULTS

HIV-positive patients without CMV retinitis showed significant differences from HIV-negative normal controls in a number of measures of the retinal nerve fiber layer. This indicated a loss of retinal ganglion cells in HIV-positive patients without retinitis. HIV-positive patients with CMV retinitis were worse in most measurements than both HIV-negative controls and HIV-positive patients without CMV.

CONCLUSIONS

Significant thinning of the retinal nerve fiber layer occurs in HIV-positive patients without infectious retinopathy, and there are further changes in the optic disk associated with CMV retinitis. Confocal scanning laser tomography may be of use in the diagnosis of early HIV-associated visual function loss.

Correlation between static automated and scanning laser entoptic perimetry in normal subjects and glaucoma patients

OBJECTIVE

To compare the effectiveness of scanning laser entoptic perimetry with static automated perimetry as a noninvasive instrument for screening for glaucomatous damage in visually asymptomatic subjects within the central 60 degrees (diameter) of vision.

DESIGN

A masked cross-sectional study comparing entoptic perimetry to achromatic threshold perimetry.

PARTICIPANTS

Twenty-three subjects and controls from the Sharp Rees-Stealy Hospital and the Shiley Eye Center at the University of California, San Diego.

TESTING

Virtual reality-based entoptic perimetry was compared with achromatic threshold perimetry.

MAIN OUTCOME MEASURES

For each testing session, we compared the presence of a disturbance in the entoptic perimetry stimulus with the presence of defects in visual function as measured by Humphrey automated visual field perimetry.

RESULTS

Scanning laser entoptic perimetry reasonably estimates the overall visual field loss for moderate-to-severe scotomas as measured by the pattern deviation in standard visual field perimetry. Scanning laser entoptic perimetry has a sensitivity from 27% to 90% and a specificity from 50% to 100% for screening moderate-to-severe visual field defects caused by glaucoma within the central 60 degrees diameter of vision.

CONCLUSIONS

Scanning laser entoptic perimetry may be an effective and inexpensive screening test in hospitals and community clinics for diagnosing visual field loss caused by glaucoma.

Screening for CMV retinitis using chromatic discrimination thresholds and achromatic contrast sensitivity

BACKGROUND

Many patients with cytomegalovirus retinitis (CMVR) are unaware of visual disturbance so screening is advocated for patients with HIV and low CD4 counts. Many tests of retinal function have been recommended but few are effective at detecting CMVR. We assess the potential of chromatic discrimination thresholds and achromatic contrast sensitivity as screening tests for patients with CMVR.

METHOD

11 HIV+ patients with CMVR, 16 age matched HIV+ patients, and 29 age matched controls were recruited. Visual acuity, chromatic discrimination thresholds, and achromatic contrast sensitivity were measured. Fundal examination was performed by slit lamp biomicroscopy for HIV+ patients. Those with CMVR were photographed and the CMVR graded from the photographs.

RESULTS

Loss of chromatic discrimination was found in patients with CMVR (tritan p<0.0005, red/green p<0.05). The same group had deterioration in achromatic contrast sensitivity at 2.2, 3.4, and 10 cpd (p<0.05). There was correlation between the zone of CMVR with chromatic gratings (tritan r=0.83, p<0.005). No statistically significant difference was found between the HIV+ patients and the controls for all tests (p>0.1).

CONCLUSIONS

HIV+ patients with CMVR have a loss of chromatic discrimination and achromatic contrast sensitivity and this may be used to screen HIV+ patients for CMVR.

Short-wavelength automated perimetry: it's role in the clinic and for understanding ganglion cell function

Short-wavelength automated perimetry (SWAP) is a more sensitive test than standard achromatic perimetry for early loss of vision due to glaucoma and other ocular and neurological diseases. SWAP is also more successful for detecting changes in vision as glaucoma progresses. Results from various visual function-specific tests, including SWAP, suggest that there are individual differences in ocular hypertensive and glaucoma eyes in the subtype of ganglion cell first affected. However, the disease targets the same retinal area for all function-specific tests that show a deficit in a given individual. Psychophysical tests of vision are critical to understand glaucoma's effect on retinal ganglion cells, to verify the success or failure of treatment including new neuroprotective agents, and to determine the relationship of genetic markers for glaucoma to the presence and progress of the disease.

Visual dysfunction in HIV-positive patients without infectious retinopathy

Persons with HIV disease are susceptible to various manifestations of retinal damage, such as infectious retinopathies (e.g., cytomegalovirus [CMV] retinitis and toxoplasmosis) and noninfectious complications (microangiopathic infarctions or cotton-wool spots [CWS]); CWS being quite common in AIDS patients. Until recently, little research focused on noninfectious ocular pathology in HIV disease. These disorders may all affect normal functioning of the visual system while funduscopic examination results appear normal. A review of the psychophysical changes, color and contrast sensitivity, peripheral visual function, electrophysiologic and morphologic changes, the relationship of vision loss and neuropsychological changes, postretinal damage, and imaging capabilities cast important new light on quality of life issues and vision function for all HIV/AIDS patients regardless of CD4 count, other measures of wellness, or treatment protocols. Entopic perimetry, a low-cost psychophysical technique screening test, allows sensitive and specific identification of very peripheral areas of visual field loss. The authors recommend its implementation and use by primary care providers, particularly for early detection of retinal damage when funduscopic examination results may appear normal.

Analysis of visual dysfunctions in HIV-positive patients without retinitis

PURPOSE

To investigate visual dysfunctions in ophthalmoscopically normal human immunodeficiency virus (HIV)-positive patients and to correlate the results to the stage of HIV disease and neuropsychological status.

METHODS

Fifty-one randomly selected eyes (26 right, 25 left) of 51 HIV-positive patients with visual acuity measurements of 20/20 or better and no ophthalmoscopically detectable disorders were prospectively examined using achromatic and short-wavelength automated perimetry, color vision testing, and contrast sensitivity testing. CD4+ T-lymphocyte count, presence of systemic infection, hemoglobin, hematocrit, serum beta 2-microglobulin levels, and results of neuropsychological testing were also analyzed.

RESULTS

On achromatic automated perimetry, 21.6% (11/51) of patients performed abnormally according to the mean defect and 27.5% (14/51) according to the Glaucoma Hemifield Test; 29.4% (15/51) performed abnormally on short-wave-length automated perimetry according to the mean defect and 23.5% (12/51) according to the Glaucoma Hemifield Test. On contrast sensitivity, 5.9% (3/51) of patients performed abnormally in the 1.5-cycles per degree (cpd) line, 2.0% (2/51) in the 3-cpd line, 23.5% (12/51) in the 6-cpd line, 25.5% (13/51) in the 12-cpd line, and 33.3% (17/51) in the 18-cpd line. On the Farnsworth-Munsell 100-hue test, 29.4% (15/51) of patients performed abnormally. After correction for multiple correlations, two statistically significant correlations were found: sum of log contrast sensitivity with achromatic automated perimetry and sum of log contrast sensitivity with the Farnsworth-Munsell 100-hue test.

CONCLUSIONS

A significant percentage of HIV-positive patients with visual acuity of 20/20 or better and no ophthalmologic evidence of retinitis performed abnormally on visual psychophysical tests. The severity of visual dysfunction was not correlated with the stage of HIV infection or the degree of neuropsychological dysfunction.