scholarly journals DA-M2Det: An Iris Classification Network for UBM Images

2021 ◽  
Vol 2112 (1) ◽  
pp. 012011
Author(s):  
Luquan Wang ◽  
Junxing Lao ◽  
Lingfeng Yang ◽  
Yaguang Zeng ◽  
Yong Chen

Abstract Primary angle closure glaucoma (PACG) is primarily diagnosed by ophthalmologists through morphological analysis of the iris in ultrasonic biomicrocopy(UBM). In recent years, Deep convolutional neural networks (CNNs) show potential for quick category definition in eye disease. According to the characteristics of iris in UBM images, we proposed a network (DenseNet and Attention gate) DA-M2Det to automatic classification iris morphology. Firstly, in the framework of M2Det network, We used the backbone of DenseNet to replace the VGG backbone of M2Det, better extraction of basic feature layers. Secondly, three scales of attention gate (AG) was added to the Thinned U-shape Module (TUM), enable the network to pay more attention to the iris region. Finally, we use the retraining method to further improve the accuracy of iris classification. The classification results of VGG-16, M2Det, ResNet-50 and DA-M2Det networks are compared experimentally. The results show that, in three different iris shapes (including arch, flat and depression), DA-M2Det achieves an average classification accuracy of 85%, which is higher than that of the other three networks. Experimental results show that DA-M2Det can accurately classify irises into three categories, assisting ophthalmologists to quickly diagnose the cause of glaucoma and accurately perform clinical treatment thereby.

Author(s):  
Rouzbeh Amini ◽  
Victor H. Barocas

The constant flow of aqueous humor (AH) in the anterior eye provides avascular tissues, notably the lens and cornea, with oxygen and nutrients (Fig. 1a). The hydrodynamics of AH and the iris contour are directly related to each other and abnormality of one may cause abnormal behavior in the other one. For example, in primary angle closure glaucoma, the abnormal anteriorly-located iris blocks the outflow pathway of AH. Increased AH pressure, in return, may push the iris more towards the anterior and worsen the blockage.


Author(s):  
Fumiaki Tanaka ◽  
Naoki Shibatani ◽  
Kazumi Fujita ◽  
Hiroaki Ikesue ◽  
Satoru Yoshimizu ◽  
...  

Abstract Background Primary angle closure disease (PACD) is a type of glaucoma in which the intraocular pressure (IOP) is increased because of the blockage of the anterior chamber angle. Medications contraindicated for patients with PACD, such as anticholinergics, cause mydriasis, and can elevate IOP. However, anticholinergics are currently contraindicated only for primary angle closure glaucoma (PACG) in Japanese package inserts. In this study, we investigated the prescription status of medications contraindicated for PACD, such as anticholinergics, in patients with PACD scheduled for eye surgeries. Methods Forty-three Japanese patients diagnosed with PACD at Kobe City Eye Hospital, Japan, and scheduled hospitalization for eye surgeries between December 2017 and July 2018, were included. Data, including sex, age, diagnosis, IOP, anterior chamber depth, and patients’ regular medications prior to hospitalization, were collected for each patient from the electronic medical records. Results The number of patients with chronic primary angle closure (CPAC) and acute primary angle closure (APAC) was 35 (81.4%) and 8 (18.6%), respectively. Among all the 43 patients with PACD, 8 (18.6%) received 15 medications that are potentially contraindicated for PACD by non-ophthalmologist. According to medication categories, benzodiazepine hypnotics were the most commonly prescribed. Among the 8 patients with APAC, 2 (25.0%) had routinely received medications contraindicated for PACD. The median number of all kinds of prescriptions on the day of hospitalization was significantly higher for patients who received medications contraindicated for PACD than for those who did not receive them (p = 0.010). Conclusions About 20% of patients with PACD received medications potentially contraindicated for PACD, such as anticholinergics. Attention should be paid to patients prescribed multiple drugs for adverse events, such as increase in intraocular pressure.


2021 ◽  
pp. 112067212110121
Author(s):  
Guido Barosco ◽  
Roberta Morbio ◽  
Francesca Chemello ◽  
Roberto Tosi ◽  
Giorgio Marchini

Purpose: This report describes a case of bilateral primary angle closure (PAC) progressing to unilateral end-stage primary angle closure glaucoma (PACG) associated with treatment for coronavirus disease-19 (COVID-19) infection. Methods: A 64-year-old man came to our attention because of blurred vision after a 2-month hospital stay for treatment of COVID-19 infection. Examination findings revealed PACG, with severe visual impairment in the right eye and PAC in the left eye due to plateau iris syndrome. The patient’s severe clinical condition and prolonged systemic therapy masked the symptoms and delayed the diagnosis. Medical chart review disclosed the multifactorial causes of the visual impairment. Ultrasound biomicroscopy (UBM) aided in diagnosis and subsequent therapy. Results: The cause behind the primary angle closure and the iridotrabecular contact was eliminated by bilateral cataract extraction, goniosynechialysis, and myotic therapy. Conclusions: COVID-19 treatment may pose an increased risk for PAC. Accurate recording of patient and family ophthalmic history is essential to prevent its onset. Recognition of early signs of PAC is key to averting its progression to PACG.


Sign in / Sign up

Export Citation Format

Share Document