Uncovering Language Disparity of ChatGPT on Retinal Vascular Disease Classification: Cross-Sectional Study

BACKGROUND

Benefiting from rich knowledge and the exceptional ability to understand text, large language models like ChatGPT have shown great potential in English clinical environments. However, the performance of ChatGPT in non-English clinical settings, as well as its reasoning, have not been explored in depth.

OBJECTIVE

This study aimed to evaluate ChatGPT's diagnostic performance and inference abilities for retinal vascular diseases in a non-English clinical environment.

METHODS

In this cross-sectional study, we collected 1226 fundus fluorescein angiography reports and corresponding diagnoses written in Chinese and tested ChatGPT with 4 prompting strategies (direct diagnosis or diagnosis with a step-by-step reasoning process and in Chinese or English).

RESULTS

Compared with ChatGPT using Chinese prompts for direct diagnosis that achieved an F1-score of 70.47%, ChatGPT using English prompts for direct diagnosis achieved the best diagnostic performance (80.05%), which was inferior to ophthalmologists (89.35%) but close to ophthalmologist interns (82.69%). As for its inference abilities, although ChatGPT can derive a reasoning process with a low error rate (0.4 per report) for both Chinese and English prompts, ophthalmologists identified that the latter brought more reasoning steps with less incompleteness (44.31%), misinformation (1.96%), and hallucinations (0.59%) (all P<.001). Also, analysis of the robustness of ChatGPT with different language prompts indicated significant differences in the recall (P=.03) and F1-score (P=.04) between Chinese and English prompts. In short, when prompted in English, ChatGPT exhibited enhanced diagnostic and inference capabilities for retinal vascular disease classification based on Chinese fundus fluorescein angiography reports.

CONCLUSIONS

ChatGPT can serve as a helpful medical assistant to provide diagnosis in non-English clinical environments, but there are still performance gaps, language disparities, and errors compared to professionals, which demonstrate the potential limitations and the need to continually explore more robust large language models in ophthalmology practice.

ANALYSIS OF TRANSFER LEARNING FOR SELECT RETINAL DISEASE CLASSIFICATION

PURPOSE

To analyze the effect of transfer learning for classification of diabetic retinopathy (DR) by fundus photography and select retinal diseases by spectral domain optical coherence tomography (SD-OCT).

METHODS

Five widely used open-source deep neural networks and four customized simpler and smaller networks, termed the CBR family, were trained and evaluated on two tasks: 1) classification of DR using fundus photography and 2) classification of drusen, choroidal neovascularization, and diabetic macular edema using SD-OCT. For DR classification, the quadratic weighted Kappa coefficient was used to measure the level of agreement between each network and ground truth-labeled test cases. For SD-OCT-based classification, accuracy was calculated for each network. Kappa and accuracy were compared between iterations with and without use of transfer learning for each network to assess for its effect.

RESULTS

For DR classification, Kappa increased with transfer learning for all networks (range of increase 0.152-0.556). For SD-OCT-based classification, accuracy increased for four of five open-source deep neural networks (range of increase 1.8%-3.5%), slightly decreased for the remaining deep neural network (-0.6%), decreased slightly for three of four CBR networks (range of decrease 0.9%-1.8%), and decreased by 9.6% for the remaining CBR network.

CONCLUSION

Transfer learning improved performance, as measured by Kappa, for DR classification for all networks, although the effect ranged from small to substantial. Transfer learning had minimal effect on accuracy for SD-OCT-based classification for eight of the nine networks analyzed. These results imply that transfer learning may substantially increase performance for DR classification but may have minimal effect for SD-OCT-based classification.

MHANet: A hybrid attention mechanism for retinal diseases classification

With the increase of patients with retinopathy, retinopathy recognition has become a research hotspot. In this article, we describe the etiology and symptoms of three kinds of retinal diseases, including drusen(DRUSEN), choroidal neovascularization(CNV) and diabetic macular edema(DME). In addition, we also propose a hybrid attention mechanism to classify and recognize different types of retinopathy images. In particular, the hybrid attention mechanism proposed in this paper includes parallel spatial attention mechanism and channel attention mechanism. It can extract the key features in the channel dimension and spatial dimension of retinopathy images, and reduce the negative impact of background information on classification results. The experimental results show that the hybrid attention mechanism proposed in this paper can better assist the network to focus on extracting thr fetures of the retinopathy area and enhance the adaptability to the differences of different data sets. Finally, the hybrid attention mechanism achieved 96.5% and 99.76% classification accuracy on two public OCT data sets of retinopathy, respectively.

Multiclass retinal disease classification and lesion segmentation in OCT B-scan images using cascaded convolutional networks

Disease classification and lesion segmentation of retinal optical coherence tomography images play important roles in ophthalmic computer-aided diagnosis. However, existing methods achieve the two tasks separately, which is insufficient for clinical application and ignores the internal relation of disease and lesion features. In this paper, a framework of cascaded convolutional networks is proposed to jointly classify retinal diseases and segment lesions. First, we adopt an auxiliary binary classification network to identify normal and abnormal images. Then a novel, to the best of our knowledge, U-shaped multi-task network, BDA-Net, combined with a bidirectional decoder and self-attention mechanism, is used to further analyze abnormal images. Experimental results show that the proposed method reaches an accuracy of 0.9913 in classification and achieves an improvement of around 3% in Dice compared to the baseline U-shaped model in segmentation.

An enhanced OCT image captioning system to assist ophthalmologists in detecting and classifying eye diseases

Human eye is affected by the different eye diseases including choroidal neovascularization (CNV), diabetic macular edema (DME) and age-related macular degeneration (AMD). This work aims to design an artificial intelligence (AI) based clinical decision support system for eye disease detection and classification to assist the ophthalmologists more effectively detecting and classifying CNV, DME and drusen by using the Optical Coherence Tomography (OCT) images depicting different tissues. The methodology used for designing this system involves different deep learning convolutional neural network (CNN) models and long short-term memory networks (LSTM). The best image captioning model is selected after performance analysis by comparing nine different image captioning systems for assisting ophthalmologists to detect and classify eye diseases. The quantitative data analysis results obtained for the image captioning models designed using DenseNet201 with LSTM have superior performance in terms of overall accuracy of 0.969, positive predictive value of 0.972 and true-positive rate of 0.969using OCT images enhanced by the generative adversarial network (GAN). The corresponding performance values for the Xception with LSTM image captioning models are 0.969, 0.969 and 0.938, respectively. Thus, these two models yield superior performance and have potential to assist ophthalmologists in making optimal diagnostic decision.

Myopic maculopathy: Current status and proposal for a new classification and grading system (ATN)

Myopia is a highly frequent ocular disorder worldwide and pathologic myopia is the 4th most common cause of irreversible blindness in developed countries. Pathologic myopia is especially common in East Asian countries. Ocular alterations associated with pathologic myopia, especially those involving the macular area-defined as myopic maculopathy-are the leading causes of vision loss in patients with pathologic myopia. High myopia is defined as the presence of a highly negative refractive error (>-6 to -8 diopters) in the context of eye elongation (26-26.5 mm). Although the terms high myopia and pathologic myopia are often used interchangeably, they do not refer to the same eye disease. The two key factors driving the development of pathologic myopia are: 1) elongation of the axial length and 2) posterior staphyloma. The presence of posterior staphyloma, which is the most common finding in patients with pathologic myopia, is the key differentiating factor between high and pathologic myopia. The occurrence of staphyloma will, in most cases, eventually lead to other conditions such as atrophic, traction, or neovascular maculopathy. Posterior staphyloma is for instance, responsible for the differences between a myopic macular hole (MH)-with and without retinal detachment-and idiopathic MH. Posterior staphyloma typically induces retinal layer splitting, leading to foveoschisis in myopic MH, an important differentiating factor between myopic and emmetropic MH. Myopic maculopathy is a highly complex disease and current classification systems do not fully account for the numerous changes that occur in the macula of these patients. Therefore, a more comprehensive classification system is needed, for several important reasons. First, to more precisely define the disease stage to improve follow-up by enabling clinicians to more accurately monitor changes over time, which is essential given the progressive nature of this condition. Second, unification of the currently-available classification systems would establish standardized classification criteria that could be used to compare the findings from international multicentric studies. Finally, a more comprehensive classification system could help to improve our understanding of the genetic origins of this disease, which is clearly relevant given the interchangeable-but erroneous-use of the terms high and pathologic myopia in genetic research.

Luu C, Theodore Smith R, H. Guymer R, Ishikawa H, S. Schuman J, Ramamohanarao K. Classification of healthy and diseased retina using SD-OCT imaging and Random Forest algorithm

In this paper, we propose a novel classification model for automatically identifying individuals with age-related macular degeneration (AMD) or Diabetic Macular Edema (DME) using retinal features from Spectral Domain Optical Coherence Tomography (SD-OCT) images. Our classification method uses retinal features such as the thickness of the retina and the thickness of the individual retinal layers, and the volume of the pathologies such as drusen and hyper-reflective intra-retinal spots. We extract automatically, ten clinically important retinal features by segmenting individual SD-OCT images for classification purposes. The effectiveness of the extracted features is evaluated using several classification methods such as Random Forrest on 251 (59 normal, 177 AMD and 15 DME) subjects. We have performed 15-fold cross-validation tests for three phenotypes; DME, AMD and normal cases using these data sets and achieved accuracy of more than 95% on each data set with the classification method using Random Forrest. When we trained the system as a two-class problem of normal and eye with pathology, using the Random Forrest classifier, we obtained an accuracy of more than 96%. The area under the receiver operating characteristic curve (AUC) finds a value of 0.99 for each dataset. We have also shown the performance of four state-of-the-methods for classification the eye participants and found that our proposed method showed the best accuracy.

Classification and characterization of acute macular neuroretinopathy with spectral domain optical coherence tomography

PURPOSE

To classify and characterize AMN lesions with SD-OCT during a follow-up as long as 5 years.

METHODS

Retrospective study of 14 patients (18 eyes) with special focus on SD-OCT. We measured thickness of inner nuclear layer (INL), outer retinal layer (ONL), and hyperreflective band at baseline and during follow-up. AMN lesions were classified as type 1 and type 2.

RESULTS

Of 14 patients (six males, eight females, mean age 29.7 years), three patients (four eyes) had type 1 and nine (12 eyes) had type 2. Two patients did not meet the criteria for AMN type 1 or 2 and were therefore classified as new subtype of AMN. In all patients, statistically significant thinning of ONL and INL was observable. Mean ONL of all patients was 90.2 ± 7.81 and 72.3 ± 15.64 μm (p < 0.05) during follow-up; mean INL was 54.4 ± 10.71 and 37.5 ± 6.18 μm (p < 0.05) in the course. In the subgroup analysis in AMN type 2, the thinning of both ONL and INL was also statistically significant (mean ONL: 87.4 ± 6.02 and 71.6 ± 12.7 μm (p < 0.05); mean INL: 48.5 ± 5.04 and 38.5 ± 5.6 μm (p < 0.05)) in the course.

CONCLUSION

SD-OCT allows for classification, characterization, and further understanding of AMN lesions. Up to now, this is one of the largest AMN case series differentiating into different subtypes and following up for up to 5 years. Furthermore, we describe a new AMN subtype characterized by initially clinically visible yellowish parafoveal lesions, subtle pigmentary changes at late stage, lack of classic dark appearance on IR reflectance, involvement of RPE/Bruch's complex, and disruption of ellipsoid zone and interdigitation zone. The patients suffered from a prolonged visual impairment and paracentral scotomata. We propose the term AMN type 3 or "paracentral acute outer maculopathy."

Vitreomacular traction syndrome: postoperative functional and anatomic outcomes

BACKGROUND AND OBJECTIVE

To analyze a variety of vitreomacular traction (VMT) morphologies to establish a major classification that better reflects the preoperative predictive factors of postoperative visual and anatomic outcomes.

PATIENTS AND METHODS

Thirty-six eyes submitted to vitrectomy surgery were categorized with a VMT pattern (V- or J-shaped) and diameter (focal < 1,500 µm or broad > 1,500 µm) based on optical coherence tomography.

RESULTS

The researchers compared different classifications of VMT. Despite similar postoperative best corrected visual acuity (BCVA) values (P = .393), cases with focal VMT had greater visual improvement (P = .027) because the preoperative BCVA was significantly lower in the focal group (P = .007). However, the BCVA improvements did not differ between the groups regarding the classic VMT morphologic patterns (P = .235).

CONCLUSION

Postoperative outcomes and macular disorders are closely related to VMT size. The adhesion diameter (focal or broad VMT) and not the classic VMT morphologic pattern (V- or J-shaped) may better predict the postoperative anatomic and functional outcomes.

[Grade III lipemia retinalis in a 14-year-old girl]

A case of grade III lipemia retinalis is reported in a 14-year-old girl presenting to the emergency department with fatigue and somnolence. Diabetic ketoacidosis diagnostic of type 1 diabetes mellitus and severe hypertriglyceridemia (23,508 mg/dL) were found on routine blood tests. The patient was admitted to the hospital, kept NPO, and intravenous insulin was started. Her symptoms rapidly improved as did the lipid panel and fundus exam. Cases of lipemia retinalis described in the literature typically occur at a blood triglyceride level above 2,000-2,500 mg/dL. A high level of chylomicrons is responsible for the milky appearance of the serum and retinal vessels. Once the blood triglyceride level decreases significantly, the fundus appearance usually returns to normal.

Retinal disorders

The retina represents part of the central nervous system (CNS). After modifying the neural signal, the axon of the last neuron enters the optic nerve and leaves the eye. In most cases of retinal disease leading to visual loss, the diagnosis will be made by an ophthalmologist after examining the ocular fundus. Some retinal disorders, however, might not be detectable at the time of examination. Those patients will be referred to a neurologist for "unexplained visual loss" when suspecting a lesion behind the optic nerve. Moreover, knowledge of potential retinal abnormalities is useful for the neurologist when seeing patients with CNS disease, which can manifest itself also in the retina. This chapter aims to give an overview about retinal disorders causing no or only few retinal abnormalities, those associated with neurological diseases, as well as the most important retinal diseases involving the tissues of the ocular fundus (vitreous body, retina, pigment epithelium, and the choroid). The most frequently used examination techniques and diagnostic tools are described. Tumors, vascular disease, especially diabetic retinopathy, age-related macular degeneration, chorioretinal inflammatory and toxic disorders, paraneoplastic retinopathies, inherited retinal dystrophies, and retinal involvement in CNS disease such as phakomatoses and multiple sclerosis are discussed.

The retinal ciliopathies

While the functions of many of the proteins located in or associated with the photoreceptor cilia are poorly understood, disruption of the function of these proteins may result in a wide variety of phenotypes ranging from isolated retinal degeneration to more pleiotropic phenotypes. Systemic findings include neurosensory hearing loss, developmental delay, situs-inversus, infertility, disorders of limb and digit development, obesity, kidney disease, liver disease, and respiratory disease. The concept of "retinal ciliopathies" brings to attention the importance of further molecular analysis of this organelle as well as provides a potential common target for therapies for these disorders. The retinal ciliopathies include retinitis pigmentosa, macular degeneration, cone-dystrophy, cone-rod dystrophy, Leber congenital amaurosis, as well as retinal degenerations associated with Usher syndrome, primary ciliary dyskinesia, Senior-Loken syndrome, Joubert syndrome, Bardet-Biedl syndrome, Laurence-Moon syndrome, McKusick-Kaufman syndrome, and Biemond syndrome. Mutations for these disorders have been found in retinitis pigmentosa-1 (RP1), retinitis pigmentosa GTPase regulator (RPGR), retinitis pigmentosa GTPase regulator interacting protein (RPGR-IP), as well as the Usher, Bardet-Biedl, and nephronophthisis genes. Other systemic disorders associated with retinal degenerations that may also involve ciliary abnormalities include: Alstrom, Edwards-Sethi, Ellis-van Creveld, Jeune, Meckel-Gruber, Orofaciodigital Type 9, and Gurrieri syndromes. Understanding these conditions as ciliopathies may help the ophthalmologist to recognize associations between seemingly unrelated diseases and have a high degree of suspicion that a systemic finding may be present.

Retinopathy in persons without diabetes: the Los Angeles Latino Eye Study

PURPOSE

To assess the prevalence of retinopathy and its relationship to sociodemographic and clinical characteristics in a population-based cohort of adult Latinos without diabetes mellitus.

METHODS

This was a population-based, cross-sectional study comprising 6357 Latinos, 40 years of age and older, from six census tracts in La Puente, Los Angeles, California. An interviewer-administered questionnaire assessed sociodemographic factors and medical history. Color fundus photographs were taken and graded in a masked manner according to a modified Airlie House Classification Grading System. Participants underwent a physical examination that included height, weight, blood pressure, random serum glucose, and glycosylated hemoglobin measurements. Univariate and multivariate logistic regression analyses were used to assess associations between sociodemographic and clinical characteristics and retinopathy in persons without diabetes.

RESULTS

The prevalence of retinopathy among individuals without diabetes in the Los Angeles Latino Eye Study (LALES) population was 6.6% (95% confidence interval 5.9%-7.4%). Stepwise logistic regression indicated that stage II hypertension (World Health Organization 2003 Guidelines), male gender, current smoking status, and obesity (body mass index >or= 30 kg/m(2)) were associated with retinopathy (odds ratio = 4.3, 1.6, 1.4, and 1.3, respectively). No statistically significant associations with retinopathy were present for Native American ancestry; country of origin; health insurance status; history of cardiovascular disease; or history of aspirin, oral contraceptive, or hormone replacement therapy.

CONCLUSIONS

The data suggest that the prevalence of retinopathy in nondiabetic individuals among Latinos of primarily Mexican ancestry is significant. Independent risk indicators for retinopathy in the study population are hypertension, male gender, current smoking status, and obesity.

Error correction and quantitative subanalysis of optical coherence tomography data using computer-assisted grading

PURPOSE

To demonstrate feature subanalysis and error correction of optical coherence tomography (OCT) data by using computer-assisted grading.

METHODS

The raw exported StratusOCT (Carl Zeiss Meditec, Inc., Dublin, CA) scan data from 20 eyes of 20 patients were analyzed using custom software (termed OCTOR) designed to allow the user to define manually the retinal borders on each radial line scan. Measurements calculated by the software, including thickness of the nine standard macular subfields, foveal center point (FCP), and macular volume, were compared between two graders and with the automated Stratus analysis. Mean and range of differences for each parameter were calculated and assessed by Bland-Altman plots and Pearson correlation coefficients. Additional cases with clinically relevant subretinal findings were selected to demonstrate the capabilities of this system for quantitative feature subanalysis.

RESULTS

Retinal thickness measurements for the various subfields and the FCP showed a mean difference of 1.7 mum (maximum, 7 microm) between OCTOR graders and a mean difference of 2.3 microm (maximum of 8 microm) between the OCTOR and Stratus analysis methods. Volume measurements between Stratus and OCTOR methods differed by a mean of 0.06 mm(3) (in reference to a mean macular volume of 6.81 mm(3)). The differences were not statistically significant, and the thicknesses correlated highly (R(2) > or = 0.98 for all parameters).

CONCLUSIONS

Manual identification of the inner and outer retinal boundaries on OCT scans can produce retinal thickness measurements consistent with those derived from the automated StratusOCT analysis. Computer-assisted OCT grading may be useful for correcting thickness measurements in cases with errors of automated retinal boundary detection and may be useful for quantitative subanalysis of clinically relevant features, such as subretinal fluid volume or pigment epithelial detachment volume.

The eye in hypertension

Hypertension has a range of effects on the eye. Hypertensive retinopathy refers to retinal microvascular signs that develop in response to raised blood pressure. Signs of hypertensive retinopathy are frequently seen in adults 40 years and older, and are predictive of incident stroke, congestive heart failure, and cardiovascular mortality--independently of traditional risk factors. Hypertension is also a major risk factor for the development of other retinal vascular diseases, such as retinal vein and artery occlusion, and ischaemic optic neuropathy. High blood pressure increases the risk of both development of diabetic retinopathy and its progression. Adequate control of blood pressure has been proven in randomised clinical trials to reduce vision loss associated with diabetic retinopathy. Finally, hypertension has been implicated in the pathogenesis of glaucoma and age-related macular degeneration. Recognition of the ocular effects of blood pressure could allow physicians to better manage patients with hypertension, and to monitor its end-organ effects.

[Classification of the forms of hypertensive retinopathy on the basis of estimation of the bioelectrical retinal potential and contrast sensitivity]

The paper gives the results of electroretinographic and psychophysical studies in hypertensive patients with first-, second-, and third-degree blood pressure (BP) elevation. The most characteristic functional symptoms of hypertensive retinopathy were defined at different stages of its development. There may be impaired retinal bioelectrical activity and diminished contrast and color sensitivity both in the presence and absence of ophthalmoscopically visible changes. Based on the findings, the authors have developed a functional classification of hypertensive retinopathy in relation to the degree of BP elevation.

Vitelliform Macular Dystrophy

PURPOSE

To investigate and integrate the photographic, angiographic, and tomographic findings from a group of patients with various stages of vitelliform macular dystrophy type 2 (VMD2; also known as Best's disease) and use this information to propose mechanisms of disease pathogenesis.

DESIGN

Retrospective observational case series.

PARTICIPANTS

Nine consecutive patients seen in a private practice referral setting by the authors.

METHODS

Patients with VMD2 were imaged with conventional fundus and autofluorescence photography, fluorescein angiography, fundus photography, and optical coherence tomography (OCT).

MAIN OUTCOME MEASURES

The integrated ocular imaging findings.

RESULTS

Early stage lesions were smaller and had accumulation of yellowish material in the central macula. This material was highly autofluorescent and appeared to be located on the outer retinal surface by OCT. Later stages were characterized by larger lesions with central clearing of the yellowish material and deposition of autofluorescent subretinal material at the outer borders of the lesion. Both early and late lesions had a subretinal fluid component with no reflectivity as detected by OCT. Fluorescein angiography showed transmission defects with a suggestion of late leakage, much like that seen in chronic central serous chorioretinopathy (CSC).

CONCLUSIONS

Similar to that seen in CSC, patients with VMD2 have an accumulation of material on the outer retina, which may represent shed photoreceptor outer segments in association with subretinal fluid.

Fred Hollows Lecture: Hypertensive retinopathy – a journey from fundoscopy to digital imaging

Hypertensive retinopathy refers to a spectrum of retinal microvascular signs that develop in response to elevated blood pressure. These signs are broadly divided into localized signs (focal retinal arteriolar narrowing, arteriovenous nicking, retinal haemorrhages, cotton wool spots, hard exudates and microaneurysms) and diffuse signs (generalized retinal arteriolar narrowing, arterial wall opacification and optic disc oedema). Although their association with systemic morbidity was recognized more than a century ago, the prognostic significance of hypertensive retinopathy has not received much attention. In large part, this is because clinical assessment of hypertensive retinopathy signs with the direct fundoscopy has proven imprecise. Data from large population-based studies in the past decade, using retinal photographic methods to define hypertensive retinopathy signs, have provided new insights into the epidemiology, systemic associations and clinical significance of hypertensive retinopathy. These studies show that hypertensive retinopathy signs are common (up to 14% of adults aged 40 years and older, even in those without clinical diabetes or hypertension) and are strongly associated with blood pressure. Various retinopathy signs predict the risk of stroke, congestive heart failure and cardiovascular mortality, independent of blood pressure and other risk factors. These data suggest that patients with hypertensive retinopathy signs may benefit from a careful cardiovascular evaluation, and appropriate risk reduction therapy if indicated. Future advances in digital retinal imaging technology will allow researchers and clinicians to better chart and monitor the vascular effects of hypertension.

Evanescent White Linear Flecks and Posterior Microphthalmos: New Features of a Recently Established Disease

BACKGROUND

Posterior microphthalmos is a rare autosomal recessive condition with normal anterior segment and small posterior segment resulting in axial hyperopia and retinal folding.

HISTORY AND SIGNS

The proband from a consanguineous Turkish family was clinically investigated at 5 months of age and followed for the next 8 years. At five months of age, refraction revealed a severe hyperopia of + 10 diopters in both eyes (OU) with a mean axial length of 16.5 mm. Fundus examination showed a dystrophic maculo-papillar bundle. Multiple whitish deep intraretinal linear lesions sparing the macula were present in the mid-periphery with no preferential orientation.

THERAPY AND OUTCOME

By 8 years of age, visual acuity was 20/25 in the right eye (OD) and 20/30 in the left eye (OS) with S + 14 OU. The whitish linear lesions had disappeared and were replaced by retinal pigment epithelium alterations. Optical coherence tomography (OCT) revealed a thickened retina with normal appearance at the site of the linear lesions.

CONCLUSIONS

This is the first report of long-term follow-up and OCT findings in this rare ocular developmental abnormality.

Idiopathic Macular Telangiectasia

OBJECTIVES

To review the frequency and nature of idiopathic macular telangiectasia and to classify the disorders based on new clinical and imaging observations.

METHODS

A combined retrospective and prospective analysis of newly diagnosed patients seen over a period of 3 years. Patients were identified based on the Gass-Blodi classification and were studied with biomicroscopy, fluorescein angiography, and optical coherence tomography.

RESULTS

Ten patients associated with aneurysmal telangiectasia (Gass-Blodi group 1) and 26 patients with perifoveal telangiectasia (Gass-Blodi group 2) were recruited. None with occlusive telangiectasia (Gass-Blodi group 3) were identified. New observations based on clinical, fluorescein angiographic, and optical coherence tomographic findings were made.

CONCLUSIONS

Our series was similar to that in the Gass-Blodi study in terms of frequency. New observations in groups 1 and 2 have expanded our knowledge of the clinical spectrum of these disorders. A simplified classification termed idiopathic macular telangiectasia with 2 distinct types (type I, or aneurysmal telangiectasia, and type II, or perifoveal telangiectasia) was proposed to produce a better understanding of the entities and to enhance teaching and research. The third type, occlusive telangiectasia, has been omitted from our classification based on its rarity and presence of capillary nonperfusion rather than macular telangiectasia as the primary abnormality.

The prevalence of bacteraemia-related retinal lesions in seriously ill patients

OBJECTIVES

In this study, we investigated the frequency and aetiology of retinal lesions in bacteraemic and septic patients and the risk factors involved.

METHODS

A total of 150 adult patients in our hospital were included in the study. After consultation with the infectious diseases specialist, the following details were recorded: demographic data, area of admission, underlying diseases, Winston's clinical condition, Charlson's co-morbidity index, McCabe's criteria for underlying disease, APACHE II scoring, community or nosocomial acquisition of bacteraemia, and micro-organism responsible. Blood cultures were obtained from all the patients at least three times. All patients were examined for ocular lesions by the same ophthalmologist 48-72 h after the first examination. Some long-term hospitalized patients were evaluated more than once.

RESULTS

Patients were divided into six groups: 18 (12%) were bacteraemic non-septic; 31 (20.7%) were septic bacteraemic; 43 (28.7%) were septic non-bacteraemic; 19 (12.7%) had systemic inflammatory response syndrome (SIRS); 16 (10.7%) were non-septic non-bacteraemic but infectious; and 23 (15.3%) were controls. We found bacteraemia-related retinal lesions (BRRLs) in 22/150 (14.7%) of the patients, 19 of whom (86.4%) were in the septic-bacteraemic group while 3 (13.6%) were in the septic non-bacteraemic group. BRRLs were observed in 19/31 (61.3%) patients in the septic-bacteraemic group. Winston and APACHE II scores were found to be higher in patients with BRRLs than in others. BRRLs were more prevalent in septic or bacteraemic patients with central nervous system (CNS) diseases (31.8%) or cancer (27.3%) than in patients with other diseases. The organism most frequently responsible for bacteraemia in patients with BRRLs was Pseudomonas aeruginosa (27.3%), and the second most common was Staphylococcus aureus (22.7%).

CONCLUSION

BRRLs are most frequent in bacteraemic-septic patients (61.3%). The underlying diseases predisposing most to BRRLs are diseases of the CNS and cancers. Ocular examination appears to be a useful aid to diagnosis of bacteraemia or sepsis.