Kajian terdahulu banyak menunjukkan perbezaan dalam dimensi okular mengikut kaum. Walau bagaimanapun hanya terdapat sedikit data mengenai dimensi okular bangsa Melayu di Malaysia yang dilaporkan. Kajian ini bertujuan untuk menetapkan nilai normal dimensi okular bangsa Melayu muda di Malaysia. Seramai 584 orang telah diundang untuk menjadi subjek untuk kajian secara sukarela. Pengukuran yang dilakukan meliputi kelengkungan dan ketebalan tengah kornea, nilai esentrisiti kornea (e), diameter iris horizontal dan vertikal yang kelihatan, saiz pupil dan bukaan palpebral. Subjek dibahagikan kepada 3 kumpulan berikut mengikut umur dan dipadankan mengikut jantina dan umur: Kumpulan 1 (7-12 tahun, n = 188), Kumpulan 2 (13 to 18 tahun, n = 196) and Kumpulan 3 (19 to 24 tahun, n = 200). Pengukuran dilakukan menggunakan topografer kornea (CTK 922 dari Haag Streit, Jerman), pakometer ultrasonik (Corneo-Gage Plus 2 dari Sonogage Incorporated) dan auto refraktometer (Auto-Ref R1 dari Canon, Jepun). Dimensi okular bangsa Melayu yang diukur didapati lebih kecil dari bangsa lain di seluruh dunia. Perbezaan yang signifikan juga didapati untuk semua pengukuran dengan peningkatan umur (p < 0.05). Keputusan kajian ini boleh dijadikan rujukan untuk nilai dimensi okular populasi Melayu muda Malaysia di masa hadapan.
Iris recognition has become a widely popular biometric system. The stable textures and features of the human iris have made such biometric systems efficient and accurate for purposes of verification and identification. The term non-ideal iris refers to a situation in which the iris is occluded by noise, including reflections, eyelashes, eyelids and so on. Most current iris recognition algorithms assume that the iris is not occluded, which is less accurate. A method using only some parts of the iris may be suitable to deal with a non-ideal iris. The current application of iris recognition systems are plagued by weaknesses such as slow processing times, especially when dealing with many irises. In this study, a sub-iris recognition technique is proposed to deal with the non-ideal iris, while reducing execution time via an embedded system using a graphical processing unit (GPU). The experiment revealed that the proposed method was accurate and fast.
Descriptions of four new species of the genus Philanthaxia Deyrolle, 1864: Philanthaxia pseudoaeneasp. n. (Thailand), Philanthaxia jaklisp. n. (Indonesia, Sumatra), Philanthaxia chalcogenioidessp. n. (Indonesia, Sabah) and Philanthaxia lombokanasp. n. (Indonesia, Lombok) are given. The new species and male genitalia are illustrated and compared with the most similar congeners. Sexual dimorphism of Philanthaxia iris Obenberger, 1938 is described and discussed.
This paper examines the chemical elements used as colour additives in cosmetic coloured contact lenses (Cos-CCL) using Field Emission Scanning Electron Microscope equipped with Energy Dispersive X-ray Spectroscopy (FESEM-EDX) analysis. The samples comprised two different Cos-CCL brands and colours (sample A1-black iris colour & B1-gray iris colour) with their respective clear contact lens counterparts as controls (sample A2 & B2). The parameters of Cos-CCL were observed carefully so that they resembled their respective controls. All the samples were analysed for chemical element characterisation by using EDX spectroscopy surface mapping analysis on both front and back surfaces. EDX spectroscopy point analysis was done on cross-section surface of Cos-CCL when colour additive pattern could not be detected by FESEM on either surface. FESEM-EDX spectroscopy analysis has revealed iron element in the colour additives of the A1 sample and aluminium elements in the B2 sample. These two elements were not present in the respective control samples. It can be concluded that iron and aluminium elements are exclusively attributed to the colour additive in Cos-CCL samples. It is important for manufacturers of Cos-CCL to disclose information of their products and create greater awareness on the risks facing users.
Iris biometric detection provides contactless authentication, preventing the spread of COVID-19-like contagious diseases. However, these systems are prone to spoofing attacks attempted with the help of contact lenses, replayed video, and print attacks, making them vulnerable and unsafe. This paper proposes the iris liveness detection (ILD) method to mitigate spoofing attacks, taking global-level features of Thepade's sorted block truncation coding (TSBTC) and local-level features of the gray-level co-occurrence matrix (GLCM) of the iris image. Thepade's SBTC extracts global color texture content as features, and GLCM extracts local fine-texture details. The fusion of global and local content presentation may help distinguish between live and non-live iris samples. The fusion of Thepade's SBTC with GLCM features is considered in experimental validations of the proposed method. The features are used to train nine assorted machine learning classifiers, including naïve Bayes (NB), decision tree (J48), support vector machine (SVM), random forest (RF), multilayer perceptron (MLP), and ensembles (SVM + RF + NB, SVM + RF + RT, RF + SVM + MLP, J48 + RF + MLP) for ILD. Accuracy, precision, recall, and F-measure are used to evaluate the performance of the projected ILD variants. The experimentation was carried out on four standard benchmark datasets, and our proposed model showed improved results with the feature fusion approach. The proposed fusion approach gave 99.68% accuracy using the RF + J48 + MLP ensemble of classifiers, immediately followed by the RF algorithm, which gave 95.57%. The better capability of iris liveness detection will improve human-computer interaction and security in the cyber-physical space by improving person validation.
Iris mammillations are dark brown, smooth, mound- or dome-shaped protuberances that are typically found on the anterior iris surface and are presumed to be congenital in origin. This congenital anomaly is usually unilateral and can be hereditary or sporadic. Lisch nodules in neurofibromatosis, tapioca melanoma of the iris, inflammatory iris granulomata and Cogan-Reese syndrome should be considered in the differential diagnosis. In this case report, the authors present a case of a bilateral iris mammillations in two siblings with congenital adrenal hyperplasia (CAH). To our knowledge, this is the first case where bilateral iris mammilations have been found to be associated with a systemic condition. Iris mammillations can be considered as one of the clinical signs in CAH in view of the pathogenesis discussed. Detailed ocular examination in CAH may reveal an increased incidence.
To report a case of spontaneous malignant glaucoma in an Asian female. To propose the term "positive vitreous pressure glaucoma" to reflect the pathophysiology, treatment and prognosis of the condition.
This manuscript describes the first detailed chemical investigation of endemic species Iris adriatica, including isolation and structure elucidation. Chemical analyses of the rhizome CH2Cl2/MeOH (2:1) extract revealed fourteen secondary metabolites, mainly isoflavonoids. Among isoflavonoids, two groups have been found: nigricin-type and tectorigenin-type. Dominant group of the isolated compounds has been nigricin-type isoflavones: nigricin, nigricin-4'-(1-O-β-D-glucopyranoside) and nigricin-4'-(1-O-β-D-glucopyranosyl (1-6)-β-D-glucopyranoside) with 2.5, 10 and 1% of the total extract, respectively. Irisxanthone - xanthone C-glucoside, β-sitosterol, benzophenone and one of its derivatives have also been found. Nigricin-type isoflavonoids and irisxanthone can be considered as possible chemotaxonomic markers for I. adriatica. 5,3',5'-Trimethoxy-6,7-methylenedioxyisoflavone-4'-(1-O-β-D-glucopyranoside) and benzophenone have been isolated from Iris species for the first time.
The use of 0.5 mg/0.05 ml of ranibizumab intracamerally, to induce regression of iris neovascularisation in a non-diabetic patient, is reported. A 55-year-old Malay man presented with left eye rubeosis and hyphaema secondary to ischaemic remnant retinal flap in his silicone filled pseudophakic eye. Regression of rubeosis and resolution of hyphaema was noted within 4 days of injection of intracameral ranibizumab, allowing repeat vitrectomy to be performed without much bleeding, thus facilitating removal of his intraocular lens and laser to remaining flap. One month postoperatively he remained comfortable with counting fingers vision similar to the pre-hyphaema period.
This paper had selected watermifoil (Myriophyllum veticillatum Linn.), softstem bulrush (Scirpus validus Vahl) and yellow-flowered iris (Iris wilsonii), in showing the water purification through different configuration. AFIs with different combination of aquatic plants were set up to purify the water quality for 50 days. This paper aimed to evaluate chemical and vegetative characteristics of each type of plant and also to find configuration of aquatic plants to maximize the contaminants removal efficiency by artificial floating island (AFI). The result indicated that the trophic waterbody promote the growth of plants and all of the AFIs have the ability to purify water and reduce contaminants. However, the most effective way is by combination of these three aquatic plants which has strong capacity to remove COD, NO3-, total nitrogen, total phosphorous and improve pH levels. Watermifoil (Myriophyllum verticillatum Linn.) is better than yellow-flowered iris (Iris wilsonii) and softstem bulrush (Scirpus validus Vahl) in disposing water pollutants.
Uncontrolled hypertension is well- known to give rise to systemic complications involving multiple central organs. Artherosclerosis leads to damage of the retinal vessels wall, contributing to venous stasis, thrombosis and finally, occlusion. Retinal vein occlusions compromise vision through development of ischaemic maculopathy, macular oedema, and rubeotic glaucoma. Laser photocoagulation remains the definitive treatment for ischaemic vein occlusion with secondary neovascularization. Timely treatment with anti- vascular endothelial growth factor prevents development of rubeotic glaucoma. We hereby report an unusual case of bilateral retinal vein occlusion complicated by rubeosis irides, which was successfully managed to improve vision and prevent rubeotic glaucoma.
Iris-based biometric systems identify individuals based on the characteristics of their iris, since they are proven to remain unique for a long time. An iris recognition system includes four phases, the most important of which is preprocessing in which the iris segmentation is performed. The accuracy of an iris biometric system critically depends on the segmentation system. In this paper, an iris segmentation system using edge detection techniques and Hough transforms is presented. The newly proposed edge detection system enhances the performance of the segmentation in a way that it performs much more efficiently than the other conventional iris segmentation methods.
Ciliary-block glaucoma occurred in one eye of a 65-year-old-male, following a combined trabeculectomy and extracapsular lens extraction for long-standing angle-closure glaucoma. After pupillary block was excluded as a cause, a posterior capsulotomy resolved the condition. This procedure was repeated successfully when a flat anterior chamber recurred on spontaneous closure of the initial capsulotomy. The ciliary block appeared to be caused by the residual zonule and lens capsule.
This retrospective study investigated the role of antivascular endothelial growth factor agents (VEGF), ranibizumab, bevacizumab and pegaptanib sodium in patients with iris neovascularisation (INV), in which 9 eyes received intraocular injections for various ischaemic ocular conditions. Ocular sequelae included recurrence of rubeosis (n=2) and hyphaema (n=2). Systemic complication included one case of cerebrovascular accident. INV regressed in all cases from day one. INV recurrence occurred in 2 cases. The mean intraocular pressure of the study eyes decreased from 25.3 mmHg to 18.3 mmHg at one month. Five eyes are medication free. Visual acuity improved in 5 eyes. Four eyes achieved a Snellen visual acuity of 6/24 or better. We conclude that the use of intraocular anti-VEGF agents are safe and effective for inducing the regression of INV. Patients with multiple systemic risk factors should be counseled on stroke risk.