MyMedR

Response: Optical Coherence Tomography Angiography of Optic Disc and Macula Vessel Density in Glaucoma and Healthy Eyes

Yip VCH, Wong HT, Yong VKY, Lim BA, Hee OK, Cheng J, et al.

J Glaucoma, 2019 07;28(7):e132-e133.

PMID: 31135585 DOI: 10.1097/IJG.0000000000001289

Matched MeSH terms: Optic Disk*

Fulltext Optic disc topography of normal tension glaucoma patients in Malaysia

Abdul Rahim A, Ismail S, Ahmad Tajudin LS, Ahmad MS

Med J Malaysia, 2013 Aug;68(4):338-42.

PMID: 24145263 MyJurnal

There are limited data in the literature on the optic disc topography in normal tension glaucoma (NTG) patients in Asian countries, especially in Southeast Asia. This study is aimed at comparing optic disc topography in NTG patients and a control group in Malaysia, and we discuss the literature on NTG studies in other Asian populations. A comparative cross-sectional study was conducted in two hospitals with glaucoma services in Malaysia from November 2010 to February 2012. A total of 109 eyes of 109 Malay patients were included in this study: 32 NTG patients and 77 subjects in the control group. All participants underwent a thorough ocular examination, including visual acuity, subjective refraction, anterior segment and fundus examinations, Humphrey visual field 24-2, intraocular pressure measurement, gonioscopy examination and fundus photography. Optic disc topography was assessed using the Heidelberg Retinal Tomograph III by an identified masked investigator in each hospital. NTG patients had a notably larger disc area (2.65 (0.41) vs 2.19 (0.43) mm(2), respectively), larger cupping (1.54 (0.43) vs 0.63 (0.40) mm(2), respectively), smaller retinal rim areas (1.12 (0.41) vs 1.56 (0.33) mm(2), respectively), higher cup volume (0.47 (0.28) vs 0.11 (0.19) mm(3), respectively), reduced rim volume (0.23 (0.13) vs 0.41 (0.16) mm(3), respectively), higher cup to disc area ratio (0.58 (0.14) vs 0.27 (0.15), respectively), higher linear cup to disc ratio (0.76 (0.09) vs 0.49 (0.17) mm(2), respectively), higher mean cup depth (0.37 (0.09) vs 0.22 (0.09) mm, respectively), higher maximum cup depth (0.77 (0.16) vs 0.59 (0.20) mm, respectively), higher mean of cup shape measure (-0.04 (0.06) vs -0.16 (0.07), respectively), and thinner mean retinal nerve fibre layer thickness (0.15 (0.15) vs 0.24 (0.07) mm, respectively) compared to the control group (p<0.05). In conclusion, most of the optic disc parameters were significantly different in NTG patients compared to healthy individuals in Malaysia. Our findings are comparable to those reported in NTG studies in other Asian countries.

Matched MeSH terms: Optic Disk*

Fulltext Evaluation of Retinal Nerve Fiber Layer Thickness and Optic Nerve Head Parameters in Obstructive Sleep Apnoea Patients

Ngoo QZ, A NF, A B, Wh WH

Korean J Ophthalmol, 2021 06;35(3):223-230.

PMID: 34120421 DOI: 10.3341/kjo.2020.0019

PURPOSE: To study the retinal nerve fiber layer (RNFL) thickness and optic nerve head (ONH) parameters in obstructive sleep apnoea (OSA) patients and their relationship with severity of the disease.

METHODS: A cross-sectional, hospital-based study. Fifty-four OSA subjects and 54 controls were recruited. Candidate that fulfil the criteria with normal ocular examinations then proceed with spectrum domain Cirrus optical coherence tomography examinations. ONH parameters and RNFL thickness were evaluated. Apnoea-hypopnoea index (AHI) of the OSA group were obtained from the medical record.

RESULTS: In OSA, mean of average RNFL thickness was 93.87 µm, standard deviation (SD) = 9.17, p = 0.008 (p < 0.05) while superior RNFL thickness was 113.59 µm, SD = 16.29, p ≤ 0.001 (p < 0.05). RNFL thickness fairly correlate with severity of the disease (AHI), superior RNFL with R = 0.293, R2 = 0.087, p = 0.030 (p < 0.05), and nasal RNFL R = 0.292, R2 = 0.085, p = 0.032. No significant difference and correlation observed on ONH parameters. In control group, mean of average RNFL thickness was 98.96 µm, SD = 10.50, p = 0.008 (p < 0.05) while superior RNFL thickness was 125.76 µm, SD = 14.93, p ≤ 0.001 (p < 0.05).

CONCLUSIONS: The mean of the average and superior RNFL thickness were significantly lower in the OSA group compare to control. Regression analysis showed RNFL thickness having significantly linear relationship with the AHI, specifically involving the superior and nasal quadrant.

Matched MeSH terms: Optic Disk*

Localization of optic disc and fovea in retinal images using intensity based line scanning analysis

Kamble R, Kokare M, Deshmukh G, Hussin FA, Mériaudeau F

Comput Biol Med, 2017 08 01;87:382-396.

PMID: 28595892 DOI: 10.1016/j.compbiomed.2017.04.016

Accurate detection of diabetic retinopathy (DR) mainly depends on identification of retinal landmarks such as optic disc and fovea. Present methods suffer from challenges like less accuracy and high computational complexity. To address this issue, this paper presents a novel approach for fast and accurate localization of optic disc (OD) and fovea using one-dimensional scanned intensity profile analysis. The proposed method utilizes both time and frequency domain information effectively for localization of OD. The final OD center is located using signal peak-valley detection in time domain and discontinuity detection in frequency domain analysis. However, with the help of detected OD location, the fovea center is located using signal valley analysis. Experiments were conducted on MESSIDOR dataset, where OD was successfully located in 1197 out of 1200 images (99.75%) and fovea in 1196 out of 1200 images (99.66%) with an average computation time of 0.52s. The large scale evaluation has been carried out extensively on nine publicly available databases. The proposed method is highly efficient in terms of quickly and accurately localizing OD and fovea structure together compared with the other state-of-the-art methods.

Matched MeSH terms: Optic Disk/pathology*

Fulltext Retinal break adjacent to the optic disc causing retinal detachment in a pathological myopia

Noor Aniah, A., Bastion, M.L.C., Mushawiahti, M.

Journal of Surgical Academia, 2017;7(2):21-23.

MyJurnal

Retinal detachment is one of the common complications of pathological myopia due to presence of retinal break.
However, retinal break commonly occurs in the peripheral retina. This case report illustrates the rare incidence of
retinal break adjacent to the optic disc, highlights the possible causes of poor visual outcome following surgical
repair as well as the possible measures to treat the complications.

Matched MeSH terms: Optic Disk

Automated identification of exudates and optic disc based on inverse surface thresholding

Yazid H, Arof H, Isa HM

J Med Syst, 2012 Jun;36(3):1997-2004.

PMID: 21318328 DOI: 10.1007/s10916-011-9659-4

This paper presents a new approach to detect exudates and optic disc from color fundus images based on inverse surface thresholding. The strategy involves the applications of fuzzy c-means clustering, edge detection, otsu thresholding and inverse surface thresholding. The main advantage of the proposed approach is that it does not depend on manually selected parameters that are normally chosen to suit the tested databases. When applied to two sets of databases the proposed method outperforms a method based on watershed segmentation.

Matched MeSH terms: Optic Disk/physiopathology*

Fulltext Optic disc topography in Malay patients with normal-tension glaucoma and primary open-angle glaucoma

Adlina AR, Alisa-Victoria K, Shatriah I, Liza-Sharmini AT, Ahmad MS

Clin Ophthalmol, 2014;8:2533-9.

PMID: 25540578 DOI: 10.2147/OPTH.S71136

There are limited data concerning the optic disc topography in normal-tension glaucoma (NTG) and primary open-angle glaucoma (POAG) patients living in Southeast Asian countries. This study aims to compare optic disc parameters in patients with NTG and POAG in Malaysia and to discuss the results in comparison with studies of NTG and POAG in other Asian countries.

Matched MeSH terms: Optic Disk

Fulltext Assessment of the optic nerve head parameters using Heidelberg retinal tomography III in preterm children

Alshaarawi S, Shatriah I, Zunaina E, Wan Hitam WH

PLoS One, 2014;9(2):e88056.

PMID: 24551076 DOI: 10.1371/journal.pone.0088056

Variations in optic nerve head morphology and abnormal retinal vascular pattern have been described in preterm children using digital image analysis of fundus photograph, optical coherence tomograph and serial funduscopy. We aimed to compare the optic nerve head parameters in preterm and term Malay children using Heidelberg Retinal Tomograph III.

Matched MeSH terms: Optic Disk/anatomy & histology; Optic Disk/pathology*

Comparison of B-scan sonographic measurements of optic cup with fundus photographic measurements

Ali NA, Subrayan V, Reddy SC, Othman F

J Clin Ultrasound, 2009 Jun;37(5):285-9.

PMID: 19280658 DOI: 10.1002/jcu.20570

To compare the measurements of the optic cup diameter with B-scan sonography with fundus photography in patients with clear ocular media and to propose a solution for the clinical problem of determining the cup-disc ratio in eyes with opaque ocular media.

Matched MeSH terms: Optic Disk/pathology; Optic Disk/ultrasonography*

Fulltext Bilateral idiopathic optic perineuritis in a young Malay woman: A case report

Ayesha Mohd Zain, Umi Kalthum Md Noh, Mushawiahti Mustapha, Norshamsiah Md. Din, Bastion, Mae Lynn Catherine

Neurology Asia, 2015;20(4):407-409.

MyJurnal

A 28-year-old Malay woman presented with severe loss of vision in both eyes associated with periocular pain on eye movement. She was completely blind at presentation and examination showed optic discs
swelling. Optic nerve imaging showed ‘doughnut sign’, characteristic of optic perineuritis. Steroid was
given over six months. Visual function improved gradually and was maintained at one year follow-up.
This case highlights the importance of differentiation between optic neuritis and optic perineuritis as
visual recovery depends on prolonged management with corticosteroid in optic perineuritis.

Matched MeSH terms: Optic Disk

Fulltext Posterior Vitreous Detachment Precipitated by Yoga

Chong SY, Fhun LC, Tai E, Chong MF, Sonny Teo KS

Cureus, 2018 Jan 24;10(1):e2109.

PMID: 29581921 DOI: 10.7759/cureus.2109

Yoga has recently been touted as a means to improve physical and mental well-being. However, no form of exercise is without its risks. A 32-year-old Chinese female with moderate myopia complained of right eye sudden onset of floaters and mild blurring of vision after the head-down posture. The visual acuity was 6/12 in the right eye and 6/9 in the left eye. A right eye fundus examination showed posterior vitreous detachment, with a small blood clot located at the inferior margin of the optic disc. The patient was diagnosed with right eye vitreous hemorrhage secondary to acute posterior vitreous detachment and was managed conservatively. Acute changes in posture, especially between an upright and a head-down position, may cause acute posterior vitreous detachment. As yoga practitioners may be required to assume this head-down position, myopic patients should be warned of the possible ocular complications of this exercise.

Matched MeSH terms: Optic Disk

Fulltext Optic Discs Swelling Procrastinates Wernicke's Encephalopathy Associated with Hyperemesis Gravidarum: A Case Report and Review of Literature

Mun-Wei L, Gayathri G, Kwang Hwee G, Ruban K, Suresh Kumar V, Shatriah I

Cureus, 2018 Jun 12;10(6):e2793.

PMID: 30112269 DOI: 10.7759/cureus.2793

Wernicke's encephalopathy following severe hyperemesis gravidarum is an uncommon clinical entity. We describe a rare manifestation of optic discs swelling in a pregnant woman that has caused a diagnostic dilemma. With high index of suspicion of clinical manifestations and radiological evidences, a clinical diagnosis of Wernicke's encephalopathy was made. Intravenous thiamine therapy was instituted, and prompt improvement of clinical signs was observed. The association of optic discs swelling and Wernicke's encephalopathy after hyperemesis gravidarum is discussed.

Matched MeSH terms: Optic Disk

Diagnosis of diabetic retinopathy: automatic extraction of optic disc and exudates from retinal images using marker-controlled watershed transformation

Reza AW, Eswaran C, Dimyati K

J Med Syst, 2011 Dec;35(6):1491-501.

PMID: 20703768 DOI: 10.1007/s10916-009-9426-y

Due to increasing number of diabetic retinopathy cases, ophthalmologists are experiencing serious problem to automatically extract the features from the retinal images. Optic disc (OD), exudates, and cotton wool spots are the main features of fundus images which are used for diagnosing eye diseases, such as diabetic retinopathy and glaucoma. In this paper, a new algorithm for the extraction of these bright objects from fundus images based on marker-controlled watershed segmentation is presented. The proposed algorithm makes use of average filtering and contrast adjustment as preprocessing steps. The concept of the markers is used to modify the gradient before the watershed transformation is applied. The performance of the proposed algorithm is evaluated using the test images of STARE and DRIVE databases. It is shown that the proposed method can yield an average sensitivity value of about 95%, which is comparable to those obtained by the known methods.

Matched MeSH terms: Optic Disk*

A Case of Polypoidal Choroidal Vasculopathy Associated With Optic Disc Drusen

Sarojini K, Ling KP, Teh WM, Ali H, Zunaina E

Cureus, 2020 Sep 07;12(9):e10297.

PMID: 33047087 DOI: 10.7759/cureus.10297

We report a case of optic disc drusen (ODD) associated with peripapillary polypoidal choroidal vasculopathy (PCV). A 62-year-old Malay lady presented with both eye ODD and the left eye associated with peripapillary subretinal hemorrhage. Ultrasound B-scan and red-free photography confirmed the optic nerve head drusen findings bilaterally. Optical coherence tomography (OCT) of the left eye showed sharply elevated peripapillary pigment epithelial detachment with subretinal fluid. The presence of peripapillary polyps with branching vascular network in indocyanine green angiography of the left eye further confirmed the diagnosis of PCV and excluded choroidal neovascularization (CNV) secondary to ODD. Subsequently, the patient was treated with a combination of verteporfin photodynamic therapy with three monthly intravitreal ranibizumab injections. Three months after the combined treatment, OCT showed completely resolved subretinal fluid. ODD can cause compression of the subretinal vessels at the optic disc that results in retinal ischemia and release of vascular endothelial growth factor, which may trigger the development of CNV or PCV. The rarity of this combination makes it interesting to study more cases of ODD with PCV. Importantly, a thorough evaluation in distinguishing the PCV from the CNV that mimics it is crucial for early detection and prompt intervention. In this case, indocyanine green angiography (ICGA) is the diagnostic method to differentiate the PCV from CNV secondary to ODD.

Matched MeSH terms: Optic Disk; Optic Disk Drusen

Fulltext Optical coherence tomography angiography of the macula and optic nerve head: microvascular density and test-retest repeatability in normal subjects

Lim CW, Cheng J, Tay ELT, Teo HY, Wong EPY, Yong VKY, et al.

BMC Ophthalmol, 2018 Dec 10;18(1):315.

PMID: 30526537 DOI: 10.1186/s12886-018-0976-y

BACKGROUND: Despite the potential usefulness of optical coherence tomography angiography in retinal and optic disc conditions, the reliability of the imaging modality remains unclear. This study set out to measure the microvascular density of macula and optic disc by mean of optical coherence tomography angiography and report the repeatability of the vessel density measurements.

METHODS: Cross sectional observational cohort study. Subjects with normal eyes were recruited. Two sets of optical coherence tomography angiography images of macula and optic nerve head were acquired during one visit. Novel in-house developed software was used to count the pixels in each images and to compute the microvessel density of the macula and optic disc. Data were analysed to determine the measurement repeatability.

RESULTS: A total of 176 eyes from 88 consecutive normal subjects were recruited. For macular images, the mean vessel density at superficial retina, deep retina, outer retina and choriocapillaries segment was OD 0.113 and OS 0.111, OD 0.239 and OS 0.230, OD 0.179 and OS 0.164, OD 0.237 and OS 0.215 respectively. For optic disc images, mean vessel density at vitreoretinal interface, radial peripapillary capillary, superficial nerve head and disc segment at the level of choroid were OD 0.084 and OS 0.085, OD 0.140 and OS 0.138, OD 0.216 and OS 0.209, OD 0.227 and OS 0.236 respectively. The measurement repeatability tests showed that the coefficient of variation of macular scans, for right and left eyes, ranged from 6.4 to 31.1% and 5.3 to 59.4%. Likewise, the coefficient of variation of optic disc scans, for right and left eyes, ranged from 14.3 to 77.4% and 13.5 to 75.3%.

CONCLUSIONS: Optical coherence tomography angiography is a useful modality to visualise the microvasculature plexus of macula and optic nerve head. The vessel density measurement of macular scan by mean of optical coherence tomography angiography demonstrated good repeatability. The optic disc scan, on the other hand, showed a higher coefficient of variation indicating a lower measurement repeatability than macular scan. Interpretation of optical coherence tomography angiography should take into account test-retest repeatability of the imaging system.

TRIAL REGISTRATION: National Healthcare Group Domain Specific Review Board ( NHG DSRB ) Singapore. DSRB Reference: 2015/00301.

Matched MeSH terms: Optic Disk/blood supply*

Fulltext Severe diabetic papillopathy mimicking non-arteritic anterior ischemic optic neuropathy (NAION) in a young patient

Mallika PS, Salowi MA, Thanaraj A, Chong MS, Tan AK, Chua CN

Med J Malaysia, 2012 Apr;67(2):228-30.

PMID: 22822654 MyJurnal

With the pathophysiology not clearly understood and fewer than 130 cases having been reported in the literature, diabetic papillopathy presents a special challenge to the ophthalmologist. We report a case of a young patient with more than 12 years of type 1 diabetes mellitus (T1DM) on insulin with poor compliance to treatment who presented with sudden bilateral loss of vision. Ocular examination, fluorescence angiography (FA) and systemic signs were conclusive of diabetic papillopathy. His fasting blood sugar level was high and serum glycosylated haemoglobin (HbA1c) indicated a long term fluctuating blood glucose control. His vision initially improved with treatment, but later deteriorated with tight glycemic control.

Matched MeSH terms: Optic Disk/pathology*

Assessment of optic disc parameters among healthy adult Malays by Heidelberg Retinal Tomograph II

Jusoh S, Shaharuddin B, Wan Hitam WH

Clin Exp Ophthalmol, 2011 Jan;39(1):15-22.

PMID: 20659136 DOI: 10.1111/j.1442-9071.2010.02385.x

This study aims to assess the optic disc characteristics in healthy adult Malays and to correlate them with age, gender and refractive errors.

Matched MeSH terms: Optic Disk/anatomy & histology*

Triple Vessel Coronary Artery Disease and Retinal Nerve Fibre Layer Thickness

Neoh YL, Neoh PF, Salleh A, Yusof ZB, Gurusamy B, Ahmad Tajudin LS

Ann Acad Med Singap, 2018 06;47(6):226-229.

PMID: 30019068

Matched MeSH terms: Optic Disk/pathology*

Non-arteritic anterior ischaemic optic neuropathy secondary to menorrhagia in a young healthy woman

Koh KL, Sonny Teo KS, Chong MF, Wan Hitam WH

BMJ Case Rep, 2018 Jun 27;2018.

PMID: 29950366 DOI: 10.1136/bcr-2018-225113

Non-arteritic anterior ischaemic optic neuropathy (NAION) may develop due to severe anaemia and hypotension which is seen in acute blood loss. The devastating visual loss is often irreversible. We report a case of NAION in a 20-year-old healthy woman, who presented on the third day of a heavy menstrual cycle with hypovolaemic shock. On day 2 of admission, she had sudden right eye blurring of vision at the superior field on awakening from sleep. Funduscopy revealed a pale and swollen right optic disc. There was a dense right superior altitudinal visual field defect. Her haemoglobin level was low (3.6 g/dL), but she refused blood transfusion due to her religious belief (Jehovah's Witness) and opted for conservative management. She later developed right optic atrophy with persistent visual field defect despite an improved haemoglobin level of 10.5 g/dL.

Matched MeSH terms: Optic Disk/pathology

47 XYY and morning glory syndrome--a unique association

Chew FL, Visvaraja S

J AAPOS, 2009 Aug;13(4):406-7.

PMID: 19487143 DOI: 10.1016/j.jaapos.2009.02.007

47 XYY syndrome is a sporadic condition in which the human male receives an extra Y chromosome. Few ocular associations have been documented. The authors report the first case of 47 XYY associated with morning glory syndrome, frontonasal meningoencephalocele, and midfacial defects.

Matched MeSH terms: Optic Disk/abnormalities*; Optic Disk/pathology

Displaying publications 1 - 20 of 52 in total