European Journal of Cardiovascular Medicine

Examination for the ocular fundus forms a vital part of the clinical assessment as it provides pivotal findings to assess the severity of illness in a patient and disease diagnosis. In the central nervous system, retina is the only part which can be visualized from outside. Similarly, the retina is the only area where vasculatures as capillaries, veins, and arteries can be visualized from outside. Hence, it is an excellent area to detect any end-organ damage and for chronic disease staging as hypertension and diabetes. The role of fundoscopy in medical emergencies for detection of papillodema with increased intracranial pressure is vital which is otherwise contraindicated for lumbar puncture.¹ 

Also, fundoscopic assessment can help in identification of the pathological process which is not evident otherwise as in assessment of cytomegalovirus infection, choroidal tubercles, disseminated candidaemia, and/or endocarditis. Despite fundus examination is vital, it is usually not adopted routinely as it needs expertise, is time consuming, and when not done accurately, it can miss findings that are clinically vital. Fundus examination is usually performed by trained ophthalmologist or physician in medical emergencies with a direct hand-held DO (direct ophthalmoscope). Other techniques that are used to assess fundus include fundus photography using a specialized fundus camera, indirect ophthalmoscopy, and slit-lamp biomicroscopy using +78D or +90D lens.² 

SFP (Smartphone fundus photography) is a novel technique that follows the principle of indirect ophthalmoscopy where fundus is photographed using a smartphone and 20D lens. It allows bedside assessment of the fundus by a person who is not ophthalmologist and is relatively an easier technique. Commercial adopters are available for aligning the lens with smartphone. Adaptor can be readily available from materials as polyvinyl chloride pipes and insulation tapes. One end of the adaptor is attached with 20D lens and on other side, smartphone is attached. Light source is provided by the flashlight of the smartphone. The images are saved and can be sent for expert opinion to the ophthalmologist. The images can be stored and retrieved when needed.³

Smartphone fundus photography plays an essential role for the outreach programmes that have limited availability for traditional fundus cameras and limited number of clinicians. It is used commonly in ophthalmology for screening diseases such as retinopathy of prematurity, glaucoma, and diabetic retinopathy. However, using retinopathy of prematurity by physicians in various medical conditions, particularly in medical emergencies has not been explored.⁴ The present study was aimed to assess the smartphone fundus photography use by physicians in the medical emergencies and compared them with the findings of DO (direct ophthalmology) by the ophthalmologist

The present prospective observational study was aimed to assess the smartphone fundus photography use by physicians in the medical emergencies and compared them with the findings of DO (direct ophthalmology) by the ophthalmologist. The study was done at Department of Ophthalmology of the Institute. Verbal and written informed consent were taken from guardians/parents of all the subjects before study participation.

The study assessed subjects that reported to the medical emergency Department of the Institute within the defined study period that were aged >18 years and were indicated for fundus evaluation for reasons as subjects having bleeding manifestations and fever of more than 1 week or unknown origin (suspected tuberculosis, infective endocarditis, HIV, etc.), indication for lumbar puncture (to rule out papilloedema), and /or altered sensorium (Glasgow Coma Scale <9). The exclusion criteria for the study were subjects that were allergic to the eye drops, glaucoma suspects (shallow anterior chamber), and subjects with prior eye surgeries.

All the subjects that met the inclusion criteria were included in the study and smartphone used for SFP in the study was GOOGLE PIXEL having 12-megapixel camera with KED (light emitting diode) flash, Following the method by Raju et al,⁵ a cardboard adaptor was made to hold the 20D lens. The initial assessment and fundus photographs were recorded by the physician and was sent to ophthalmologist for assessment.

Another physician expert in the field did DO (direct ophthalmoscopy) and time taken for both the techniques was noted and the findings recorded by the two observers were compared as smartphone fundus photography and direct ophthalmoscopy findings.

The collected data were subjected to statistical evaluation using chi-square test, Fisher’s exact test, Mann Whitney U test, and SPSS (Statistical Package for the Social Sciences) software version 24.0 (IBM Corp., Armonk. NY, USA) using ANOVA, chi-square test, and student's t-test. The significance level was considered at a p-value of <0.05.

The present prospective observational study was aimed to assess the smartphone fundus photography use by physicians in the medical emergencies and compared them with the findings of DO (direct ophthalmology) by the ophthalmologist. The present study assessed 364 subjects that presented to the medical emergencies of the Institute within the defined study period with indicated fundus examination. The smartphone fundus photography was done by the physician in all the subjects and findings were recorded in a preformed structured proforma and were compared to the direct ophthalmology findings by the ophthalmologists. Among 364 subjects, there were 58.2% (n=212) males and 41.8% (n=152) females, comorbid conditions as hypertension and diabetes were seen in 44% subjects. Other comorbid conditions seen were HIV, SLE (systemic lupus erythematosus), and hypothyroidism in 8, 4, and 10 subjects respectively.

It was seen that most common indication for fundus examination in the study subjects was fever of unknown origin followed by alteration in the sensorium. For smartphone fundus photography, fundus findings were seen in 61% (n=222) study subjects (Table 1). Among fundus findings, most common lesion was papillodema seen in 78 subjects followed by roth spots and retinal hemorrhage. In 12 study subjects, choroid tubercles were seen. Physician missed 14 findings as 2 choroid tubercles, 6 vessel abnormalities, 2 Roth spots, and 6 papilledema that were identified by ophthalmologist from the images.

The study results showed that for findings of direct ophthalmology in 222 subjects and the comparison, it was seen that 38 findings were missed from direct ophthalmology including 2 vessel wall abnormality, 4 choroid tubercles, 4 retinal haemorrhages, 4-disc pallor, 12 Roth spots, and 12 papilledemas. The overall agreement among two techniques was nearly perfect with k coefficient of 0.924. Other findings as diabetic retinopathy was seen in 18 subjects from 66 subjects that had hypertension as seen of grade 3 and 4 in 6 and 12 study subjects respectively. In 4 subjects, SLE retinopathy and HIV retinopathy was seen. All these subjects were assessed using both the techniques. Smartphone fundus photography took mean 4.81 minutes less compared to direct ophthalmology with p<0.01.

It was also seen that for other artefacts and cataract in the study subjects, in 84 subjects, cataract was seen. The smartphone fundus photography method needed 2 minutes more compared to the subjects that did not have cataract with p<0.01. Also, the images in subjects with cataract were less clear compared to subjects that had cataract. In the fundus photography, other cause of artefacts were scratches, photophobia, and excessive tears.

Table 1: Comparison of the fundus findings in study subjects as assessed using direct ophthalmology and smartphone fundus photography

The present study assessed 364 subjects that presented to the medical emergencies of the Institute within the defined study period with indicated fundus examination. The smartphone fundus photography was done by the physician in all the subjects and findings were recorded in a preformed structured proforma and were compared to the direct ophthalmology findings by the ophthalmologists. Among 364 subjects, there were 58.2% (n=212) males and 41.8% (n=152) females, comorbid conditions as hypertension and diabetes were seen in 44% subjects. Other comorbid conditions seen were HIV, SLE (systemic lupus erythematosus), and hypothyroidism in 8, 4, and 10 subjects respectively. These data were comparable to the previous studies of Muiesan ML et al⁶ in 2017 and Wintergerst MW et al⁷ in 2020 where authors assessed subjects with demographic and disease data that underwent SFP in their studies as in the present study.

The study results showed that most common indication for fundus examination in the study subjects was fever of unknown origin followed by alteration in the sensorium. For smartphone fundus photography, fundus findings were seen in 61% (n=222) study subjects (Table 1). Among fundus findings, most common lesion was papillodema seen in 78 subjects followed by roth spots and retinal hemorrhage. In 12 study subjects, choroid tubercles were seen. Physician missed 14 findings as 2 choroid tubercles, 6 vessel abnormalities, 2 Roth spots, and 6 papilledema that were identified by ophthalmologist from the images. These results were consistent with the findings of Chow SP et al⁸ in 2006 and Wintergerst MW et al⁹ in 2019 where fundus examination indications and findings reported by the authors were similar to the results of the present study.

It was seen that for findings of direct ophthalmology in 222 subjects and the comparison, it was seen that 38 findings were missed from direct ophthalmology including 2 vessel wall abnormality, 4 choroid tubercles, 4 retinal haemorrhages, 4-disc pallor, 12 Roth spots, and 12 papilledemas. The overall agreement among two techniques was nearly perfect with k coefficient of 0.924. Other findings as diabetic retinopathy was seen in 18 subjects from 66 subjects that had hypertension as seen of grade 3 and 4 in 6 and 12 study subjects respectively. In 4 subjects, SLE retinopathy and HIV retinopathy was seen. All these subjects were assessed using both the techniques. Smartphone fundus photography took mean 4.81 minutes less compared to direct ophthalmology with p<0.01. these findings were in agreement with the results of Natarajan S et al¹⁰ in 2019 and Sengupta S et al¹¹ in 2019 where results similar to present study concerning comparison of DO and SFP comparable to the present study were also reported by the authors in their studies.

Concerning the assessment of other artefacts and cataract in the study subjects, in 84 subjects, cataract was seen. The smartphone fundus photography method needed 2 minutes more compared to the subjects that did not have cataract with p<0.01. Also, the images in subjects with cataract were less clear compared to subjects that had cataract. In the fundus photography, other cause of artefacts were scratches, photophobia, and excessive tears. These results correlated with the findings from the previous studies of Dunn HP et al¹² in 2021 and Pradeep R et al¹³ in 2023 where artefacts and cataract data in SFP and DO reported by the authors was comparable to the results of the present study

Considering its limitations, the present study concludes that smartphone fundus photography has equal efficacy when compared to direct ophthalmology in the assessment of the retinal findings in subjects that have medical emergencies and can be done as the bedside examination by the physicians in the emergency.

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