Computer-aided diagnostic system for hypertensive retinopathy: A review

Hypertensive Retinopathy (HR) is a retinal disease caused by elevated blood pressure for a prolonged period. There are no obvious signs in the early stages of high blood pressure, but it affects various body parts over time, including the eyes. HR is a biomarker for several illnesses, including retinal diseases, atherosclerosis, strokes, kidney disease, and cardiovascular risks. Early microcirculation abnormalities in chronic diseases can be diagnosed through retinal examination prior to the onset of major clinical consequences. Computer-aided diagnosis (CAD) plays a vital role in the early identification of HR with improved diagnostic accuracy, which is time-efficient and demands fewer resources. Recently, numerous studies have been reported on the automatic identification of HR. This paper provides a comprehensive review of the automated tasks of Artery-Vein (A/V) classification, Arteriovenous ratio (AVR) computation, HR detection (Binary classification), and HR severity grading. The review is conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. The paper discusses the clinical features of HR, the availability of datasets, existing methods used for A/V classification, AVR computation, HR detection, and severity grading, and performance evaluation metrics. The reviewed articles are summarized with classifiers details, adoption of different kinds of methodologies, performance comparisons, datasets details, their pros and cons, and computational platform. For each task, a summary and critical in-depth analysis are provided, as well as common research issues and challenges in the existing studies. Finally, the paper proposes future research directions to overcome challenges associated with data set availability, HR detection, and severity grading.

Association Of Hypertensive Retinopathy With Angiographic Severity Of Coronary Artery Disease Determined By Syntax Score

BACKGROUND

Hypertension is a leading cause of morbidity among developing and developed countries. Hypertensive Retinopathy is a micro vascular complication of long standing hypertension while CAD is a macro vascular complication. The main objective of the study was to determine the association between worsening grade of hypertensive retinopathy with angiographic severity of coronary artery disease (CAD) measured by Syntax Score.

METHODS

This was a cross sectional study which was conducted after approval from IRB. All patients with history of hypertension, who underwent coronary angiography, were included in the study. After a detailed history and physical exam, all included patients were subjected to fundoscopy. Patients were categorized into 4 groups according to Keith et al classification of hypertensive retinopathy: No HR, Mild HR, Moderate HR and Severe HR. Patients were also categorized into three groups on the basis of angiographic severity of CAD by syntax score (SS): Mild CAD (SS<22), Moderate CAD (SS: 22-32) and Severe CAD (SS>32). Data was analysed in SPSS Version 20.0. Categorical and continuous variables were described as frequencies/percentages and Mean±SD respectively.

RESULTS

A total of 370 patients were included in the study out of which 205 were males with a mean age of 55.3±10.07 years. Mean duration of hypertension was 8.1±2.7 years with a mean SBP of 130.1±37.2 mmHg and mean DBP of 90.3±17.3 mmHg. Patients with no HR, mild HR, moderate HR and severe HR had a mean SS of 11.7±4.5, 17.1±3.9, 26.3±5.1 and 37.9±5.1 respectively. Significant association was found between HR and severity of CAD with a chi square value of 285.53 (p<0.001). PORs for worsening grade of HR with severity of CAD increased from 0.341 (p<0.001) for mild HR to 2.33 (p<0.001) times for severe HR.

CONCLUSIONS

A higher grade of hypertensive retinopathy is significantly associated to a higher angiographic severity of CAD by syntax score.

Bilateral Obstructive Uropathy Caused by Congenital Bladder Diverticulum Presenting as Hypertensive Retinopathy

A congenital bladder diverticulum (CBD) is caused by inherent muscular weakness instead of obstruction of the bladder outlet. The major clinical conditions are recurrent urinary tract infection (UTI) and voiding dysfunction. This report describes a 15-year-old male adolescent who developed sudden visual disturbance resulting from hypertensive retinopathy. The cause of hypertension was bilateral obstructive uropathy caused by enlarged paraureteral bladder diverticula. After the non-functioning right kidney and ureter and the bilateral diverticula were removed, the left ureter was reimplanted in the bladder. Pathologic findings showed chronic pyelonephritis and partial loss of the bladder musculature in the diverticular wall. This observation indicates that dilated CBD can cause latent UTI, ureteral obstruction, hydronephrosis, and secondary hypertension.

Serum uric acid concentration is associated with hypertensive retinopathy in hypertensive chinese adults

BACKGROUND

This cross sectional investigation included 12,966 subjects with hypertension, a cohort of the China Stroke Primary Prevention Trial (CSPPT), a randomized, multicenter clinical trial. This study aimed to explore the correlation between serum uric acid (SUA) concentration and hypertensive retinopathy in hypertensive adults.

METHODS

Diagnosis of hypertensive retinopathy was determined by non-mydriatic fundus photography and classified with Keith-Wagener-Barker (KWB) system. The correlation of SUA levels with hypertensive retinopathy prevalence and severity was assessed by statistical analysis.

RESULTS

9848 (75.95%) subjects were diagnosed with hypertensive retinopathy with the following retinopathy grade distribution: grade 1: 58.80%, grade 2: 14.81%, and grade 3-4: 2.34%. SUA levels were significantly associated with hypertensive retinopathy prevalence. Patients with hypertensive retinopathy had higher SUA levels than those without hypertensive retinopathy. Patients in the highest uric acid quartile had an odds ratio for hypertensive retinopathy of 1.21 compared to patients in the lowest uric acid quartile (OR = 1.21, 95% CI: 1.05-1.40, P = 0.008). When compared to the non-hyperuricemia group, those in the hyperuricemia group had an odds ratio for hypertensive retinopathy of 1.18(OR = 1.18, 95% CI: 1.05-1.33, P = 0.004). Every 1 mg/dl increase in uric acid concentration was significantly associated with a 6% higher odds of hypertensive retinopathy (OR = 1.06, 95% CI: 1.02-1.10, P = 0.002).

CONCLUSIONS

The prevalence of hypertensive retinopathy was high (75.95%) among hypertensives in our patients cohort. In addition, SUA concentration was significantly associated with hypertensive retinopathy.