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Sample records for tortuous retinal arteries

  1. Straight versus tortuous retinal arteries in relation to blood pressure and genetics

    DEFF Research Database (Denmark)

    TaarnhØj, Nina Charlotte; Munch, I C

    2008-01-01

    BACKGROUND/AIMS: To assess the relative influence of genetic and environmental factors on retinal arterial tortuosity and the association between tortuosity and various health indices in healthy young to middle-aged persons. METHODS: This cross-sectional study included 57 monozygotic and 52 dizygotic same-sex healthy twin pairs, aged 20 to 46 years, who were characterised by determination of retinal vessel diameters, arterial blood pressure, blood glucose, body mass index, smoking habits and retinal arterial tortuosity, using a three-level grading scale (straight, wavy, tortuous). Heritability of retinal arterial tortuosity was estimated using structural equation modelling. RESULTS: Of 218 subjects, 79 (36.2%) had straight retinal arteries, 110 (50.5%) had wavy arteries, and 29 (13.3%) had tortuous arteries. Heritability of tortuosity was 82% (CI(95 )64, 92%), with unshared environmental factors accounting for the remaining 18% (CI(95 )8, 36%). Increasing values of mean arterial blood pressure and body massindex were both associated with decreasing levels of retinal arterial tortuosity. CONCLUSION: There was a large variation in tortuosity of retinal arteries in these healthy subjects and the predominant determinant was genetic influence, accounting for 82% of the observed variation in tortuosity.

  2. Straight versus tortuous retinal arteries in relation to blood pressure and genetics

    DEFF Research Database (Denmark)

    Taarnhøj, N C B B; Munch, I C; Sander, B; Kessel, L; Hougaard, J L; Kyvik, K; Sørensen, T I A; Larsen, M

    2008-01-01

    BACKGROUND/AIMS: To assess the relative influence of genetic and environmental factors on retinal arterial tortuosity and the association between tortuosity and various health indices in healthy young to middle-aged persons. METHODS: This cross-sectional study included 57 monozygotic and 52 dizygotic same-sex healthy twin pairs, aged 20 to 46 years, who were characterised by determination of retinal vessel diameters, arterial blood pressure, blood glucose, body mass index, smoking habits and ret...

  3. Thyroid abnormality secondary to tortuous carotid artery

    International Nuclear Information System (INIS)

    A 59-year-old man was referred to the nuclear medicine service for a thyroid scan, as his neck was thick and the thyroid was not palpable. In the past the patient had undergone head and neck irradiation for acne. A 123I-thyroid scan was interpreted as a ''cold'' nodule in the lower pole of the right lobe, but thyroid ultrasound showed no thyroid abnormality. Repeat ultrasound examination eventually showed a tortuous carotid artery behind the lower pole of the right lobe of the thyroid that corresponded to the ''cold'' defect. (orig.)

  4. New techniques for intracranial stent navigation in patients with tortuous arteries

    International Nuclear Information System (INIS)

    We wanted to describe several new techniques of intracranial stenting that are helpful for navigating the stent delivery system in the tortuous carotid or vertebral arteries. Between May 1998 and June 2004, 65 patients with 73 symptomatic, stenotic intracranial arteries (more than 50%) were successfully treated with stent-assisted angioplasty. In eleven of the total cases, the standard technique failed to navigate the stent delivery system into the objective lesion because of the tortuous path of the carotid or vertebral arteries. In these cases, several new techniques were used to overcome the vessels' tortuous path. The several new techniques were 1) the waiting method (20-30 minutes) after advancement of microwire across the lesion; 2) the double wires technique using an additional microwire; and 3) the coaxial double guiding catheters technique using an additional smaller guiding catheter. Five lesions were located in the middle cerebral arteries, four were in the supraclinoid internal carotid arteries, and two were in the distal vertebral arteries. In all difficult cases, intracranial artery stenting was performed successfully by using the several new techniques. The waiting method made smooth stent navigation possible in 5 cases, the double wire technique was successful in 4 cases and the coaxial double guiding catheter technique was successful in 2 case. There was no complication related to the new techniques. In difficult cases where the standard technique failed to navigate the stent delivery system into the objective lesion because of the vessels' tortuous path, these new techniques for intracranial stent navigation were usefully implemented

  5. New techniques for intracranial stent navigation in patients with tortuous arteries

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hyun Wook; Koo, Young Baek; Lee, Tae Hong; Kim, Hak Jin; Lee, Jun Woo; Kim, Chang Won; Kim, Suk; Choo, Ki Seok; Jeong, Yeon Joo; Lee, Suk Hong [Pusan National University Hospital, Pusan (Korea, Republic of)

    2005-07-15

    We wanted to describe several new techniques of intracranial stenting that are helpful for navigating the stent delivery system in the tortuous carotid or vertebral arteries. Between May 1998 and June 2004, 65 patients with 73 symptomatic, stenotic intracranial arteries (more than 50%) were successfully treated with stent-assisted angioplasty. In eleven of the total cases, the standard technique failed to navigate the stent delivery system into the objective lesion because of the tortuous path of the carotid or vertebral arteries. In these cases, several new techniques were used to overcome the vessels' tortuous path. The several new techniques were 1) the waiting method (20-30 minutes) after advancement of microwire across the lesion; 2) the double wires technique using an additional microwire; and 3) the coaxial double guiding catheters technique using an additional smaller guiding catheter. Five lesions were located in the middle cerebral arteries, four were in the supraclinoid internal carotid arteries, and two were in the distal vertebral arteries. In all difficult cases, intracranial artery stenting was performed successfully by using the several new techniques. The waiting method made smooth stent navigation possible in 5 cases, the double wire technique was successful in 4 cases and the coaxial double guiding catheter technique was successful in 2 case. There was no complication related to the new techniques. In difficult cases where the standard technique failed to navigate the stent delivery system into the objective lesion because of the vessels' tortuous path, these new techniques for intracranial stent navigation were usefully implemented.

  6. Iliac artery occlusion with "oxbow lake" formation following stent deployment in a tortuous external iliac artery during EVAR: a case report.

    Science.gov (United States)

    Culverwell, Adam D; Kent, Patrick; Puppala, Sapna

    2011-10-01

    In this case report, we describe a complication that we term the "oxbow lake" deformity. This phenomenon occurs when a tortuous elongated external iliac artery segment is artificially straightened by an iliac stent resulting in kinking and compression of a redundant loop with lumen compromise. We describe the anatomy, corrective treatment, and outcome. This occurrence is potentially foreseeable with tortuous vascular anatomy and recognition can allow appropriate management planning avoiding complications for the patient. PMID:21788283

  7. Retinal artery occlusions in children.

    Science.gov (United States)

    Dharmasena, Aruna; Wallis, Simon

    2014-01-01

    The purpose of this study is to present a case of RAO in a 13 year old girl with a preceding history of hyperextension of the neck at her hairdressers for a long duration and use of her mobile phone handset resting it against the side of her neck presumably exerting some pressure on carotids during the same time. Materials and methods of this study was reported as case report and review of literature. A 13 year-old girl presented with the left supero-nasal scotoma due to an inferior temporal branch retinal artery occlusion (BRAO). She underwent extensive investigations and no underlying cause was discovered. She gave a history of cervical extension over a long period of time while having the hair coloured twice in the preceding week. She also mentioned that she was using her mobile phone more or less continuously during both these occasions keeping it against her neck. Given the above history it is possible that the pressure on the ipsilateral carotid arteries or the prolong neck extension may have been responsible for the formation of a platelet embolus resulting in the BRAO. In conclusion, although cerebro-vascular accidents due to 'beauty parlor stroke syndrome' (JAMA 269:2085-2086, 1993) have been reported previously it has not been reported in children to our knowledge. On the other hand, 'beauty parlor stroke syndrome' occurs due to a dissection of the vertebral arteries or due to mechanical compression of the vertebral arteries during the prolonged hyperextension of the neck. The central retinal artery originates from the internal carotid circulation and it is highly unlikely for an embolus to enter the retinal circulation from the vertebral arteries. Therefore, the authors favour the possibility that the compulsive use of a mobile phone exerting pressure on the carotid arteries for a long time may have led to the formation of an embolus and subsequent RAO in this case. PMID:23440575

  8. Branch retinal artery occlusion in Susac's syndrome

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    Ricardo Evangelista Marrocos de Aragão

    2015-02-01

    Full Text Available Susac's syndrome is a rare disease attribuited to a microangiopathy involving the arterioles of the cochlea, retina and brain. Encefalopathy, hearing loss, and visual deficits are the hallmarks of the disease. Visual loss is due to multiple, recurrent branch arterial retinal occlusions. We report a case of a 20-year-old women with Susac syndrome presented with peripheral vestibular syndrome, hearing loss, ataxia, vertigo, and vision loss due occlusion of the retinal branch artery.

  9. Branch retinal artery occlusion associated with congenital retinal macrovessel.

    Science.gov (United States)

    Goel, Neha; Kumar, Vinod; Seth, Anisha; Ghosh, Basudeb

    2014-05-01

    A congenital retinal macrovessel (CRM) is a large retinal vessel, usually a vein, which traverses through the central macula and has large tributaries extending on both sides of the horizontal raphe. In the majority of cases, CRM have no effect on visual acuity, although in rare cases, macular hemorrhage, foveolar cysts, serous macular detachment, and the presence of the anomalous vessel in the foveola can affect vision. We describe a case of CRM with decreased vision secondary to a branch retinal artery occlusion (BRAO). To the best of our knowledge, this association has not been reported previously. PMID:25136239

  10. Guyon's canal syndrome due to tortuous ulnar artery with DeQuervain stenosing tenosynovitis, ligamentous injuries and dorsal intercalated segmental instability syndrome, a rare presentation: a case report

    OpenAIRE

    Zeeshan, Muhammad; Ahmed, Farhan; Kanwal, Darakhshan; Khalid, Qazi Saad Bin; Ahmed, Muhammad Nadeem

    2009-01-01

    The Guyon's canal syndrome is a well known clinical entity and may have significant impact on patient's quality of life. We report a case of 43-year-old male who presented with complaints of pain and numbness in right hand and difficulty in writing for past one month. On imaging diagnosis of Guyon's canal syndrome because of tortuous ulnar artery was made with additional findings of DeQuervain's stenosing tenosynovitis and dorsal intercalated segmental instability syndrome with ligamentous in...

  11. Retinal artery embolization: a rare presentation of calcific aortic stenosis.

    Science.gov (United States)

    Reimers, C D; Williams, R J; Berger, M; Wisnicki, H J; Tranbaugh, R F

    1996-03-01

    Retinal artery embolization is an unusual but serious complication of calcific aortic stenosis. However, it is rare for retinal embolization to be the presenting feature of aortic stenosis. This report describes a young patient who presented with an acute retinal artery occlusion secondary to calcific aortic valve disease, and discusses the rationale for early surgical intervention. PMID:8674266

  12. Guyon's canal syndrome due to tortuous ulnar artery with DeQuervain stenosing tenosynovitis, ligamentous injuries and dorsal intercalated segmental instability syndrome, a rare presentation: a case report.

    Science.gov (United States)

    Zeeshan, Muhammad; Ahmed, Farhan; Kanwal, Darakhshan; Khalid, Qazi Saad Bin; Ahmed, Muhammad Nadeem

    2009-01-01

    The Guyon's canal syndrome is a well known clinical entity and may have significant impact on patient's quality of life. We report a case of 43-year-old male who presented with complaints of pain and numbness in right hand and difficulty in writing for past one month. On imaging diagnosis of Guyon's canal syndrome because of tortuous ulnar artery was made with additional findings of DeQuervain's stenosing tenosynovitis and dorsal intercalated segmental instability syndrome with ligamentous injury and subsequently these were confirmed on surgery.Although it is a rare syndrome, early diagnosis and treatment prevents permanent neurological deficits and improve patient's quality of life. PMID:20076781

  13. Central retinal artery occlusion following cosmetic blepharoplasty.

    OpenAIRE

    Kelly, P W; May, D. R.

    1980-01-01

    A case is presented of a 70-year-old white male who underwent a bilateral cosmetic lower lid blepharoplasty with fat removal. He subsequently developed a right orbital haemorrhage which resulted in the occlusion of the central retinal artery. The patient had no light perception with his right eye for approximately 1 hour, but vision was eventually restored to 20/20 after emergency therapeutic measures. There are many possible causes of visual loss following blepharoplasty, with orbital haemor...

  14. Metabolic syndrome and central retinal artery occlusion

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    Kosanovi?-Jakovi? Natalija

    2005-01-01

    Full Text Available Background. The accumulation of risk factors for central retinal artery occlusion can be seen in a single person and might be explained by the metabolic syndrome. Case report. We presented the case of a 52-year-old man with no light perception in his right eye. The visual loss was monocular and painless, fundoscopy showed central retinal artery occlusion and the laboratory investigation showed the raised erythrocyte sedimentation rate of 105 mm/h and the raised C-reactive protein of 22 mg/l. Specific laboratory investigations and fluorescein angiography excluded the presence of vasculitis, collagen vascular diseases, hypercoagulable state and antiphospholipid syndrome. Conclusion. The patient met all the five of the National Cholesterol Education Program (NCEP criteria for the metabolic syndrome: hypertension, abnormal lipid profile, abnormal glucose metabolism, obesity and hyperuricemia. Measurement of C-reactive protein is useful for the assessment of therapeutic systemic effect on any abnormality in the metabolic syndrome. Individual therapy for all risk factors in the metabolic syndrome is necessary to prevent complications such as cardiovascular, retinal vascular diseases and stroke.

  15. PHACE association with intracranial, oropharyngeal hemangiomas, and an atypical patent ductus arteriosus arising from the tortuous left subclavian artery in a premature infant

    Science.gov (United States)

    Choi, Jang Hwan; Lee, Jung Ha; Kim, Hee Sup

    2012-01-01

    PHACE association is a rare neurocutaneous condition in which facial hemangiomas associate with a spectrum of posterior fossa malformations, arterial cerebrovascular anomalies, cardiovascular anomalies, and eye anomalies. We reported a case of PHACE association in a premature infant showing facial, intracranial, and oropharyngeal hemangiomas with evidence of the Dandy-Walker variant and complicated cardiovascular anomalies, including a right-sided aortic arch and an atypical patent ductus arteriosus arising from a tortuous left subclavian artery. To our knowledge, intracranial hemangiomas are rare in PHACE association, and a concomitant oropharyngeal hemangioma has not been previously reported in the PHACE association literature. In infants presenting with large, plaque-like facial hemangiomas, it is important to conduct active cardiovascular and neurological evaluations. Special attention should be given to the laryngoscopic examination to search for additional hemangiomas in the airway. PMID:22359528

  16. PHACE association with intracranial, oropharyngeal hemangiomas, and an atypical patent ductus arteriosus arising from the tortuous left subclavian artery in a premature infant

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    Do-Hyun Kim

    2012-01-01

    Full Text Available PHACE association is a rare neurocutaneous condition in which facial hemangiomas associate with a spectrum of posterior fossa malformations, arterial cerebrovascular anomalies, cardiovascular anomalies, and eye anomalies. We reported a case of PHACE association in a premature infant showing facial, intracranial, and oropharyngeal hemangiomas with evidence of the Dandy-Walker variant and complicated cardiovascular anomalies, including a right-sided aortic arch and an atypical patent ductus arteriosus arising from a tortuous left subclavian artery. To our knowledge, intracranial hemangiomas are rare in PHACE association, and a concomitant oropharyngeal hemangioma has not been previously reported in the PHACE association literature. In infants presenting with large, plaque-like facial hemangiomas, it is important to conduct active cardiovascular and neurological evaluations. Special attention should be given to the laryngoscopic examination to search for additional hemangiomas in the airway.

  17. Thrombophilic screening in retinal artery occlusion patients

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    Valeria Nagy

    2008-10-01

    Full Text Available Valeria Nagy1, Lili Takacs1, Zita Steiber1, György Pfliegler2, Andras Berta11Department of Ophthalmology, 2Division of Rare Diseases, University of Debrecen Medical and Health Science Center, Debrecen, HungaryBackground: Retinal artery occlusion (RAO is an ischemic vascular damage of the retina, which frequently leads to sudden, mostly irreversible loss of vision. In this study, blood thrombophilic factors as well as cardiovascular risk factors were investigated for their relevance to this pathology. Thrombophilic risk factors so far not evaluated were included in the study.Patients and methods: 28 RAO patients and 81 matched control subjects were examined. From blood samples, protein C, protein S, antithrombinopathy, and factor V (Leiden mutation (FV, factor II gene polymorphism, factor VIII C level, plasminogen activity, lipoprotein(a and fibrinogen levels, hyperhomocysteinemia and presence of anticardiolipin – antiphospholipid antibodies were investigated. Possibly relevant pathologies such as diabetes mellitus, hypertension, and ischemic heart disease were also registered. Statistical analysis by logistic regression was performed with 95% confidence intervals.Results: In the group of patients with RAO only the incidence of hypertension (OR: 3.33, 95% CI: 1.30–9.70, p = 0.014 as an average risk factor showed significant difference, but thrombophilic factors such as hyperfibrinogenemia (OR: 2.9, 95% CI: 1.29–6.57, p = 0.010 and the presence of FV (Leiden mutation (OR: 3.9, 95% CI: 1.43–10.96, p = 0.008 increased the chances of developing this disease.Conclusions: Our results support the assumption that thrombophilia may contribute to the development of RAO besides vascular damage due to the presence of cardiovascular risk factors. Further studies are needed, however, to justify the possible use of secondary prophylaxis in form of anticoagulant/antiplatelet therapy.Keywords: retinal arterial occlusion, risk factors, thrombophilia

  18. Ischaemia-reperfusion injury in central retinal artery occlusion.

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    Saxena, Sandeep; Mishra, Nibha; Meyer, Carsten H; Akduman, Levent

    2013-01-01

    A 53-year-old man presented with sudden painless diminution of vision in his right eye for 3 days. His fundus examination showed diffuse whitening of the retina with a cherry red spot at the fovea with cilioretinal artery sparing. On fluorescein angiography delayed arteriovenous transit was observed. Three-dimensional spectral domain optical coherence tomography was used to assess retinal nerve fibre layer thickness and average macular central subfield thickness on days 3, 7, 30 and 90. Marked retinal oedema due to ischaemia was observed on day 3 of occurrence of central retinal artery occlusion. On day 7, significant decrease in retinal nerve fibre thickness and macular thickness was noted suggestive of acute reperfusion injury. Retinal nerve fibre layer thickness and macular thickness returned to near normal on day 30 due to restoration of blood supply with wash out of stress mediators. Retinal atrophy was observed on day 90. PMID:24145508

  19. Presumed toxoplasmic central retinal artery occlusion and multifocal retinitis with perivascular sheathing

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    Arai H

    2014-04-01

    Full Text Available Haruka Arai,1 Tsutomu Sakai,1 Kiichiro Okano,1 Ranko Aoyagi,1 Ayano Imai,2 Hiroshi Takase,2 Manabu Mochizuki,2 Hiroshi Tsuneoka11Department of Ophthalmology, Jikei University School of Medicine, Tokyo, Japan; 2Department of Ophthalmology and Visual Science, Tokyo Medical and Dental University, Tokyo, JapanAbstract: Central retinal artery occlusion (CRAO and multifocal retinitis with perivascular sheathing are rare in ocular toxoplasmosis. We report a case of toxoplasmic CRAO and multifocal retinitis with perivascular sheathing. A healthy 83-year-old male developed left panuveitis. Funduscopic examination of the left eye showed a swollen optic disc and sheathing of the retinal artery with a dense vitreous haze and a white retinal lesion. Serum anti-toxoplasma antibodies were positive in a latex agglutination assay. Vitrectomy was performed to improve visualization of the retinal lesions and for examination of causative microorganisms. A postoperative fundus examination revealed CRAO with optic disc involvement and multifocal retinitis with perivascular sheathing. Qualitative multiplex polymerase chain reaction detected the Toxoplasma gondii B1 gene in ocular fluid from both the aqueous and vitreous humor. The presumed diagnosis of ocular toxoplasmosis was made and treatment was started with prednisone and acetylspiramycin with subsequent improvement. Two months later, the patient developed active retinochoroiditis in the left eye. After 6 weeks of anti-toxoplasma therapy, the disease involuted. Retinal vascular occlusions and multifocal retinitis with perivascular sheathing are rare in toxoplasmosis. This is the first case report of toxoplasmic CRAO and multifocal retinitis with perivascular sheathing. The diagnosis of ocular toxoplasmosis should be considered in patients with retinal artery occlusions and multifocal retinitis with perivascular sheathing associated with inflammation.Keywords: ocular toxoplasmosis, toxoplasma retinochoroiditis, retinal vascular occlusion, polymerase chain reaction, vitrectomy

  20. Branch retinal artery occlusion associated with congenital retinal macrovessel

    OpenAIRE

    Goel, Neha; Kumar, Vinod; Seth, Anisha; Ghosh, Basudeb

    2014-01-01

    A congenital retinal macrovessel (CRM) is a large retinal vessel, usually a vein, which traverses through the central macula and has large tributaries extending on both sides of the horizontal raphe. In the majority of cases, CRM have no effect on visual acuity, although in rare cases, macular hemorrhage, foveolar cysts, serous macular detachment, and the presence of the anomalous vessel in the foveola can affect vision. We describe a case of CRM with decreased vision secondary to a branch re...

  1. Visual prognosis following treatment of acute central retinal artery obstruction.

    OpenAIRE

    Augsburger, J. J.; Magargal, L E

    1980-01-01

    The authors report the visual outcome in 34 consecutive cases of treated acute central retinal artery obstruction. Visual acuity equal to or better than 6/30 was recovered in 35% of the cases. The presenting visual acuity and duration of visual impairment appear to correlate with visual prognosis.

  2. Ocular neovascularization in eyes with a central retinal artery occlusion or a branch retinal artery occlusion

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    Mason lll JO

    2015-06-01

    Full Text Available John O Mason III,1,2 Shyam A Patel,1 Richard M Feist,1,2 Michael A Albert Jr,1,2 Carrie Huisingh,1 Gerald McGwin Jr,1,3 Martin L Thomley1,2 1Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, AL, USA; 2Retina Consultants of Alabama, Callahan Eye Foundation Hospital, Birmingham, AL, USA; 3Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, AL, USA Purpose: To investigate the ocular neovascularization (ONV rate in eyes with a branch retinal artery occlusion (BRAO or a central retinal artery occlusion (CRAO, and to study factors that may influence the ONV rate secondary to CRAO.Methods: This was a retrospective case series of consecutive patients (286 total eyes: 83 CRAOs and 203 BRAOs who were diagnosed with a retinal artery occlusion from 1998 to 2013 at the Retina Consultants of Alabama and University of Alabama at Birmingham, Birmingham, AL, USA. Generalized estimating equations were used to evaluate the association between hypothesized risk factors and ONV development.Results: Twelve (14.5% of the 83 eyes with a CRAO developed ONV. Eleven of 12 eyes (91.7% had iris neovascularization, ten of 12 eyes (83.3% had neovascular glaucoma, and two of 12 eyes (16.7% had neovascularization of the optic disc. The average time for ONV development secondary to CRAO was 30.7 days, ranging from the date of presentation to 137 days. Only two (<1.0% of the 203 eyes with a BRAO developed iris neovascularization. Diabetes mellitus type 2 was a risk factor for ONV development following a CRAO with an adjusted odds ratio of 5.2 (95% confidence interval: 1.4–19.8 (P=0.02.Conclusion: ONV is an important complication of CRAO and is a less-frequent complication of BRAO. Patients with a CRAO, especially those with diabetes mellitus type 2, should be closely monitored for the first 6 months for ONV. Keywords: neovascularization, neovascular glaucoma, retinal artery occlusion, central retinal artery occlusion, branch retinal artery occlusion, diabetes mellitus

  3. Retinal vessels caliber assessment in patients with arterial hypertension

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    N. S. Semenova

    2014-07-01

    Full Text Available Purpose: to evaluate the diagnostic capability of automated retinal vessels (RV caliber estimation for hypertensive angiopathy.Methods: this study included 146 patients (292 eyes with arterial hypertension. All the subjects underwent fundus photography and RV caliber estimation. the latter was performed using newly developed computer-based method for automated vessel detection and central retinal arteriolar and venular equivalents determination (CRAE & CRVE. Sensitivity, specificity, and reproducibility of the method were estimated.Results: the method of RV caliber assessment showed good reproducibility. the overall specificity and sensitivity were 74% and 80.77%, respectively. Computer-based method of retinal vascular caliber assessment revealed higher predictive value comparing with ophthalmoscopic assessment (AUC = 0.903 and 0.85, respectively. Retinal arteriolar and venular caliber and AVR tend to decrease with age. Higher blood pressure is associated with narrower retinal arterioles.Conclusion: Novel method of RV caliber estimation demonstrated high information value. these findings are in good agreementwith data from major population-based studies.

  4. Macroaneurisma arterial retinal. Presentación de un caso.

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    Aimé Broche Hernández

    2011-08-01

    Full Text Available Los macroaneurismas retinianos son dilataciones saculares de las arterias retinianas, con mayor frecuencia en arcadas temporales, que se detectan en pacientes de edad avanzada con hipertensión arterial y/o enfermedad vascular generalizada; son ligeramente más frecuentes en mujeres. Se presenta un caso clínico con ruptura de un macroaneurisma, que fue tratado con fotocoagulación con láser y evolucionó favorablemente.

  5. Central retinal artery occlusion resembling Purtscher-like retinopathy

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    Etomi T

    2011-08-01

    Full Text Available Takuji Kurimoto1, Norio Okamoto2, Hidehiro Oku1, Yuko Kanbara1, Tomohiko Etomi1, Masahiro Tonari1, Tsunehiko Ikeda11Department of Ophthalmology, Osaka Medical College, Takatsuki, Japan; 2Okamoto Eye Clinic, Suita, Osaka, JapanAbstract: This paper reports three cases of central retinal artery occlusion (CRAO with Purtscher-like retinopathy and good recovery of visual function. The three cases of CRAO had similar fundus changes, ie, cotton wool patches surrounding the optic disc and whitening of the retina surrounding the fovea with a cherry red spot. Fluorescein angiography showed a delay of arm-to-retina circulation time and a partial defect of choroid circulation. Although the three cases were treated by different regimens of steroid pulse therapy and antiplatelet therapy, visual function recovered well and all disturbances of the retinal and choroid circulations resolved. Although eyes with a CRAO normally have a poor visual prognosis, our three cases responded well to the treatments and recovered good visual function. Thus, cases showing fundus changes similar to our three cases may have a pathogenesis different from that of a complete CRAO.Keywords: central retinal artery occlusion, cotton wool patches, Purtscher retinopathy, steroid therapy

  6. Imaging of Dual Ophthalmic Arteries: Identification of the Central Retinal Artery

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    Louise Louw

    2014-01-01

    Full Text Available Identification of the origin of the central retinal artery (CRA is imperative in tailoring angiographic studies to resolve a given clinical problem. A case with dual ophthalmic arteries (OAs, characterized by different origins and distinct branching patterns, is documented for training purposes. Pre-clinical diagnosis of a 9-year-old child who presented with a sharp wire in the left-side eyeball was primarily corneal laceration. For imaging, a selected six-vessel angiographic study with the transfemoral approach was performed. Embolization was not required and the wire could be successfully removed. Right-side OA anatomy was normal, while left-side dual OAs with external carotid artery (ECA and internal carotid artery (ICA origins were seen. The case presented with a left-side meningo-ophthalmic artery (M-OA anomaly via the ECA, marked by a middle meningeal artery (MMA (origin: Maxillary artery; course: Through foramen spinosum with normal branches (i.e. anterior and posterior branches, and an OA variant (course: Through superior orbital fissure with a distinct orbital branching pattern. A smaller OA (origin: ICA; course: Through optic foramen with a distinct ocular branching pattern presented with the central retinal artery (CRA. The presence of the dual OAs and the M-OA anomaly can be explained by disturbed evolutionary changes of the primitive OA and stapedial artery during development. The surgical interventionist must be aware of dual OAs and M-OA anomalies with branching pattern variations on retinal supply, because of dangerous extracranial-intracranial anastomotic connections. It is of clinical significance that the origin of the CRA from the ICA or ECA must be determined to avoid complications to the vision.

  7. Analysis of emboli and blood flow in the ophthalmic artery to understand retinal artery occlusion.

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    Kaufmann, Tim A S; Leisser, Christoph; Gemsa, Jeannie; Steinseifer, Ulrich

    2014-12-01

    Retinal artery occlusion (RAO) is a common ocular vascular occlusive disorder that may lead to partial or complete retinal ischemia with sudden visual deterioration and visual field defects. Although RAO has been investigated since 1859, the main mechanism is still not fully understood. While hypoperfusion of the ophthalmic artery (OA) due to severe stenosis of the internal carotid artery might lead to RAO, emboli are assumed to be the main reason. Intra-arterial thrombolysis is not a sufficient treatment for RAO, and current research is mainly focused on risk factors. In this study, a computational fluid dynamic model is presented to analyse flow conditions and clot behaviour at the junction of the internal carotid artery and OA based on a realistic geometry from a RAO patient. Clot diameters varied between 5 and 200 ?m, and the probability of clots reaching the OA or being washed into the brain was analysed. Results show sufficient blood flow and perfusion pressure at the end of OA. The probability that clots from the main blood flow will to be washed into the brain is 7.32 ± 1.08%. A wall shear stress hotspot is observed at the curvature proximal to the internal carotid artery/OA junction. Clots released from this hotspot have a higher probability of causing RAO. The occurrence of such patient-specific pathophysiologies will have to be considered in the future. PMID:25029079

  8. Automated Method for Identification and Artery-Venous Classification of Vessel Trees in Retinal Vessel Networks

    OpenAIRE

    Joshi, Vinayak S.; Reinhardt, Joseph M.; Garvin, Mona K.; Abramoff, Michael D

    2014-01-01

    The separation of the retinal vessel network into distinct arterial and venous vessel trees is of high interest. We propose an automated method for identification and separation of retinal vessel trees in a retinal color image by converting a vessel segmentation image into a vessel segment map and identifying the individual vessel trees by graph search. Orientation, width, and intensity of each vessel segment are utilized to find the optimal graph of vessel segments. The separated vessel tree...

  9. Preservation of retinal structure and function after cilioretinal artery occlusion: a case report.

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    Brown, Craig J

    2016-01-01

    Cilioretinal artery occlusion is a cause of sudden, often catastrophic loss of central vision. There are no established effective treatments. Recently, a patient presented 24 hours after a cilioretinal artery occlusion, following a cardiac catheterization prior to which her blood thinners had been discontinued. Lacking an effective way to address the severe retinal ischemic oxidative stress, she was offered, under compassionate use, a multivitamin complex designed to address retinal ischemia and oxidative stress. Significant components of this product are L-methylfolate and n-acetyl cysteine. The patient experienced a rapid unexpected improvement in vision and preservation of retinal structure, suggesting that marked improvement in retinal artery occlusions outcomes may be possible as late as 24 hours postocclusion. This is the third reported case of cilioretinal artery occlusion associated with cardiac catheterization. PMID:26929671

  10. 3D Reconstruction of the Retinal Arterial Tree Using Subject-Specific Fundus Images

    Science.gov (United States)

    Liu, D.; Wood, N. B.; Xu, X. Y.; Witt, N.; Hughes, A. D.; Samcg, Thom

    Systemic diseases, such as hypertension and diabetes, are associated with changes in the retinal microvasculature. Although a number of studies have been performed on the quantitative assessment of the geometrical patterns of the retinal vasculature, previous work has been confined to 2 dimensional (2D) analyses. In this paper, we present an approach to obtain a 3D reconstruction of the retinal arteries from a pair of 2D retinal images acquired in vivo. A simple essential matrix based self-calibration approach was employed for the "fundus camera-eye" system. Vessel segmentation was performed using a semi-automatic approach and correspondence between points from different images was calculated. The results of 3D reconstruction show the centreline of retinal vessels and their 3D curvature clearly. Three-dimensional reconstruction of the retinal vessels is feasible and may be useful in future studies of the retinal vasculature in disease.

  11. The central retinal artery occlusion in the right eye followed by a branch retinal artery occlusion in the left eye four days later

    Directory of Open Access Journals (Sweden)

    Cagatay Caglar

    2013-01-01

    Full Text Available A 65-year-old woman was admitted to our clinic with complaints of sudden, painless, decrease in vision, and sectoral visual field defect in the left eye and later presented to our clinic again with a history of sudden loss of vision in her right eye. In this case study we reported that the patient had branch retinal artery occlusion (BRAO in the left eye and at the same time progressing central retinal artery occlusion (CRAO in the right eye.

  12. Autofluorescence and high-definition optical coherence tomography of retinal artery occlusions

    Directory of Open Access Journals (Sweden)

    Raeba Mathew

    2010-10-01

    Full Text Available Raeba Mathew, Evangelia Papavasileiou, Sobha SivaprasadLaser and Retinal Research Unit, Department of Ophthalmology, King’s College Hospital, Denmark Hill, London, UKBackground: The purpose of this study is to illustrate the fundus autofluorescence and high-definition optical coherence tomography (HD-OCT features of acute and long-standing retinal artery occlusions.Design: Retrospective case series.Participants: Patients with acute and chronic retinal and cilioretinal artery occlusions are included in this series.Methods: A detailed clinical examination, color fundus photographs, autofluorescence, and HD-OCT of the subjects were performed.Results: HD-OCT demonstrates the localized and well-demarcated thickening of the inner retina in the acute phase of arterial occlusions that correlates with the areas of blocked autofluorescence caused by the cloudy swelling of the retina. The areas of blocked autofluorescence disappear with chronicity of the disease and this corresponds to the thinning of the inner retinal layers on HD-OCT.Conclusion: Heidelberg OCT and autofluorescence are useful tools to assess retinal arterial occlusions especially in subjects with unexplained visual field loss.Keywords: autofluorescence, high definition OCT, retinal artery occlusion

  13. Branch retinal artery occlusion in Susac's syndrome / Oclusão de ramo arterial da retina na Síndrome de Susac

    Scientific Electronic Library Online (English)

    Ricardo Evangelista Marrocos de, Aragão; Lorena Maria Araújo, Gomes; Ieda Maria Alexandre, Barreira; Francisco Holanda, Oliveira Neto; Ariane Sá Vieira, Bastos.

    2015-02-01

    Full Text Available Síndrome de Susac é uma microangiopatia rara que afeta as arteríolas da cóclea, retina e encéfalo. Encefalopatia, perda auditiva e baixa da acuidade visual formam a tríade clássica da doença. A baixa de acuidade visual ocorre devido a múltiplas e recorrentes oclusões de ramo arterial da retina. Rela [...] tamos o caso de uma paciente de 20 anos com síndrome de Susac apresentando síndrome vestibular periférica, perda auditiva, vertigem, ataxia e baixa da acuidade visual por oclusão de ramo arterial de retina. Abstract in english Susac's syndrome is a rare disease attribuited to a microangiopathy involving the arterioles of the cochlea, retina and brain. Encefalopathy, hearing loss, and visual deficits are the hallmarks of the disease. Visual loss is due to multiple, recurrent branch arterial retinal occlusions. We report a [...] case of a 20-year-old women with Susac syndrome presented with peripheral vestibular syndrome, hearing loss, ataxia, vertigo, and vision loss due occlusion of the retinal branch artery.

  14. Protein kinase C in porcine retinal arteries and neuroretina following retinal ischemia-reperfusion

    DEFF Research Database (Denmark)

    Gesslein, Bodil; Gustafsson, Lotta; Wackenfors, Angelica; Ghosh, Fredrik; Malmsjö, Malin

    2009-01-01

    Identification of the intracellular signal-transduction pathways activated in retinal ischemia may be important in revealing novel pharmacological targets. To date, most studies have focused on identifying neuroprotective agents. The retinal blood vessels are key organs in circulatory failure, an...

  15. Evidence for an enduring ischaemic penumbra following central retinal artery occlusion, with implications for fibrinolytic therapy.

    Science.gov (United States)

    McLeod, David; Beatty, Stephen

    2015-11-01

    The rationale behind hyperacute fibrinolytic therapy for cerebral and retinal arterial occlusion is to rescue ischaemic cells from irreversible damage through timely restitution of tissue perfusion. In cerebral stroke, an anoxic tissue compartment (the "infarct core") is surrounded by a hypoxic compartment (the "ischaemic penumbra"). The latter comprises electrically-silent neurons that undergo delayed apoptotic cell death within 1-6 h unless salvaged by arterial recanalisation. Establishment of an equivalent hypoxic compartment within the inner retina following central retinal artery occlusion (CRAO) isn't widely acknowledged. During experimental CRAO, electroretinography reveals 3 oxygenation-based tissue compartments (anoxic, hypoxic and normoxic) that contribute 32%, 27% and 41% respectively to the pre-occlusion b-wave amplitude. Thus, once the anoxia survival time (?2 h) expires, the contribution from the infarcted posterior retina is irreversibly extinguished, but electrical activity continues in the normoxic periphery. Inbetween these compartments, an annular hypoxic zone (the "penumbra obscura") endures in a structurally-intact but functionally-impaired state until retinal reperfusion allows rapid recovery from electrical silence. Clinically, residual circulation of sufficient volume flow rate generates the heterogeneous fundus picture of "partial" CRAO. Persistent retinal venous hypoxaemia signifies maximal extraction of oxygen by an enduring "polar penumbra" that permeates or largely replaces the infarct core. On retinal reperfusion some days later, the retinal venous oxygen saturation reverts to normal and vision improves. Thus, penumbral inner retina, marginally oxygenated by the choroid or by residual circulation, isn't at risk of delayed apoptotic infarction (unlike hypoxic cerebral cortex). Emergency fibrinolytic intervention is inappropriate, therefore, once the duration of CRAO exceeds 2 h. PMID:26113210

  16. Spontaneous Central Retinal Artery Occlusion in a Teenager with Sickle Cell Trait

    OpenAIRE

    Pai, Sivakami A; Hebri, Sudhira Pai; Dekhain, Moza A.

    2015-01-01

    Sickle cell trait (SCT) is traditionally considered a benign condition by ophthalmologists. Several studies have reported ocular complications in SCT, but these complications have been described as a consequence of trauma, exertion, and associated systemic disorders. We here in the report a case of an Arab teen boy, who presented with a sudden loss of vision in his left eye of 1 h duration. The ocular examination revealed acute central retinal artery occlusion. He underwent a series of labora...

  17. Intravitreal Bevacizumab for the Treatment of Neovascular Glaucoma Associated With Central Retinal Artery Occlusion

    OpenAIRE

    Sagong, Min; Kim, Jinseon; Chang, Woohyok

    2009-01-01

    We report three cases of neovascular glaucoma secondary to central retinal artery occlusion (CRAO) which were effectively managed with intravitreal bevacizumab (IVB) followed by panretinal photocoagulation (PRP). Neovascular glaucoma without peripheral anterior synechiae developed between one and five weeks following CRAO onset. All patients received 0.75 mg (0.03 ml) IVB. In all patients, complete regression of the iris and anterior chamber angle neovascularization was confirmed within one w...

  18. Combined central retinal artery and vein occlusion secondary to systemic non-Hodgkin?s lymphoma

    OpenAIRE

    Shukla Dhananjay; Arora Amit; Hadi Khazaei; Kumar Mahesh; Baddela Satish; Kim Ramasamy

    2006-01-01

    We report a rare case of low-grade systemic B-cell non-Hodgkin?s lymphoma (NHL) causing central retinal artery and vein occlusion, which was the only manifestation of disease recurrence. A young man with resolved systemic NHL underwent fluorescein angiography, magnetic resonance imaging and computed tomography to investigate a severe unilateral visual loss. A combined vascular occlusion was observed in the right eye. Neuroimaging detected optic nerve infiltration; but no systemic/ cent...

  19. Clinicopathological correlation of parapapillary atrophy in monkeys with experimental glaucoma and temporary central retinal artery occlusion

    Directory of Open Access Journals (Sweden)

    Jost B Jonas

    2014-01-01

    Full Text Available Objective: To investigate the clinicopathological correlation of parapapillary atrophy. Materials and Methods: The study included 16 eyes of rhesus monkeys (Macaca mulatta - 4 eyes with experimental glaucoma, 11 eyes after experimental temporary occlusion of the central retinal artery, and 1 normal eye. On histological sections, we measured zones with different histological characteristics.On fundus photographs, alpha zone and beta zone of parapapillary atrophy were measured and correlated with the histological data. Results: The size of the clinical alpha zone of parapapillary atrophy was significantly correlated with the size of the histological region with irregularities of the retinal pigment epithelium (P = 0.05; correlation coefficient r = 0.49 and with the size of the histological region with a decreased density of retinal photoreceptors (P = 0.01; r = 0.60. The size of clinical beta zone of parapapillary atrophy significantly correlated with the size of the histological region with complete loss of the retinal pigment epithelium (P <0.001; r = 0.91, with the size of the histological zone with a complete loss of photoreceptors (P <0.001; r = 0.81, and with the size of the histological zone with a closed choriocapillaris (P <0.001; r = 0.89. Conclusions: The clinically seen alpha zone of parapapillary atrophy correlates with histological parapapillary irregularities of the retinal pigment epithelium and decreased density of retinal photoreceptors. The clinically seen beta zone of parapapillary atrophy correlates with histological complete loss of the retinal pigment epithelium and of the photoreceptors, and a closure of the choriocapillaris.

  20. Multifocal central serous chorioretinopathy with photoreceptor-retinal pigment epithelium diastasis in heritable pulmonary arterial hypertension

    DEFF Research Database (Denmark)

    Li, Xiao Qiang; Pryds, Anders

    2015-01-01

    PURPOSE: To report atypical central serous chorioretinopathy and choroidal thickening in a patient with heritable pulmonary arterial hypertension. METHODS: A 40-year-old man with heritable pulmonary arterial hypertension presented with blurred vision in his left eye and was followed up for 1 year with clinical examination, enhanced depth optical coherence tomography, fluorescein and indocyanine green angiography, and fundus photography. RESULTS: At presentation, atypical central serous chorioretinopathy with multiple retinal pigment epithelial detachments, a thick subfoveal choroid, and dilated choroidal vessels were seen in the patient's symptomatic left eye. After treatment for pulmonary hypertension, the serous detachments disappeared and choroidal thickness gradually decreased over a period of 4 weeks and remained unchanged at 13 months of follow-up. CONCLUSION: Central serous chorioretinopathy and choroidal thickening that responded to treatment of pulmonary arterial hypertension suggest a pathophysiological link between pulmonary arterial hypertension and central serous chorioretinopathy, perhaps mediated by choroidal venous stasis.

  1. No-Reflow Phenomenon in Central Retinal Artery Occlusion: Incidence, Risk Factors, and Clinical Implications

    Science.gov (United States)

    Ahn, Seong Joon; Park, Kyu Hyung; Ryoo, Na-Kyung; Hong, Jeong-Ho; Jung, Cheolkyu; Yoon, Chang-Hwan; Han, Moon-Ku; Woo, Se Joon

    2015-01-01

    Purpose To investigate the incidence and risk factors of the no-reflow phenomenon in central retinal artery occlusion (CRAO) patients and to determine its effects on visual and anatomic outcomes. Methods In 102 eyes with CRAO in which arterial recanalization was obtained within 1 week from baseline, fluorescein angiography images obtained at baseline and 1 week were retrospectively reviewed. The no-reflow phenomenon in the retina was defined as macular capillary nonperfusion following arterial recanalization on fluorescein angiographs. We investigated the incidence and risk factors for the no-reflow phenomenon and compared the anatomical and visual outcomes between eyes with and without the phenomenon. Results Among the 102 CRAO eyes with arterial recanalization, 39 exhibited the no-reflow phenomenon, resulting in an incidence of 38.2%. The incidence among the eyes with treatment-induced and spontaneous recanalization was 43.4% and 15.8%, respectively, and it increased with the CRAO stage. CRAO stage and increased central macular thickness were risk factors for the phenomenon, with an odds ratio of 4.47 [95% confidence interval (CI), 1.19–16.8; P = 0.027] and 1.69 (95% CI, 1.12–2.55; P = 0.012) per 100-?m increase, respectively. The visual outcome was significantly poorer and retinal atrophy and photoreceptor disruption was greater in eyes with the no-reflow phenomenon than in those without. Conclusions The no-reflow phenomenon may occur after arterial recanalization in approximately one-third of CRAO patients and can affect anatomical and visual outcomes. This phenomenon may provide an additional explanation regarding the permanent retinal damage and vision loss in eyes with CRAO. PMID:26599539

  2. Arterial blood flow characteristics in central retinal vein occlusion and effects of panretinal photocoagulation treatment: an investigation by colour Doppler imaging

    OpenAIRE

    Avunduk, A M; Dinc, H.; Kapicioglu, Z.; Ugurlu, S.; Dayanir, V.; Korkmaz, E.

    1999-01-01

    AIMS—To determine whether an increase in vascular resistance in the central retinal and ophthalmic arterial circulations contributes to the development of central retinal vein occlusion (CRVO), or haemodynamic alterations in central retinal and ophthalmic arteries occur secondary to the vein occlusion as increased intravascular pressure is transferred through the capillary bed to the arterial side and the effect of panretinal photocoagulation treatment on these circulations in ischaemic cases...

  3. Automatic determination of the artery vein ratio in retinal images

    Science.gov (United States)

    Niemeijer, Meindert; van Ginneken, Bram; Abràmoff, Michael D.

    2010-03-01

    A lower ratio between the width of the arteries and veins (Arteriolar-to-Venular diameter Ratio, AVR) on the retina, is well established to be predictive of stroke and other cardiovascular events in adults, as well as an increased risk of retinopathy of prematurity in premature infants. This work presents an automatic method that detects the location of the optic disc, determines the appropriate region of interest (ROI), classifies the vessels in the ROI into arteries and veins, measures their widths and calculates the AVR. After vessel segmentation and vessel width determination the optic disc is located and the system eliminates all vessels outside the AVR measurement ROI. The remaining vessels are thinned, vessel crossing and bifurcation points are removed leaving a set of vessel segments containing centerline pixels. Features are extracted from each centerline pixel that are used to assign them a soft label indicating the likelihood the pixel is part of a vein. As all centerline pixels in a connected segment should be the same type, the median soft label is assigned to each centerline pixel in the segment. Next artery vein pairs are matched using an iterative algorithm and the widths of the vessels is used to calculate the AVR. We train and test the algorithm using a set of 25 high resolution digital color fundus photographs a reference standard that indicates for the major vessels in the images whether they are an artery or a vein. We compared the AVR values produced by our system with those determined using a computer assisted method in 15 high resolution digital color fundus photographs and obtained a correlation coefficient of 0.881.

  4. Retinal abnormalities in CADASIL: a retrospective study of 18 patients

    Science.gov (United States)

    Cumurciuc, R; Massin, P; Paques, M; Krisovic, V; Gaudric, A; Bousser, M; Chabriat, H

    2004-01-01

    Aim: To report retinal findings in symptomatic CADASIL patients. Methods: Assessment of visual acuity (VA), testing of visual fields (VF), funduscopic examination (FE), and fluorescein angiography (FA) were carried out in 18 symptomatic patients. Results: No visual symptoms were presented by our patients. VA was normal in all. Ophthalmologic abnormalities were found in 8 patients. VF were normal except for a right hemianopia in one subject due to ischemic stroke. FE and FA revealed significant abnormalities in seven other subjects (mean age: 55 years; range: 39–74): nerve fibre loss (n = 4), cotton wool spots (n = 3), sheathed arteries (n = 1), and tortuous arteries (n = 1). Only one patient with both tortuous arteries and nerve fibre loss had multiple vascular risk factors, and another patient with cotton wool spots was a current smoker. Discussion: FE and FA revealed silent retinal abnormalities in CADASIL patients with nerve fibre loss in 22% and cotton wool spots in 17%. The presence of these abnormal retinal findings does not seem related to the severity of the disorder but may be considered as peripheral markers of this genetic disease. PMID:15201374

  5. Central Retinal and Posterior Ciliary Artery Occlusion After Intralesional Injection of Sclerosant to Glabellar Subcutaneous Hemangioma

    International Nuclear Information System (INIS)

    The aim of this study is to describe vision loss caused by central retinal artery and posterior ciliary artery occlusion as a consequence of sclerotherapy with a polidocanol injection to a glabellar hemangioma. An 18-year-old man underwent direct injection with a 23-gauge needle of 1 mL of a polidocanol-carbon dioxide emulsion into the glabellar subcutaneous hemangioma under ultrasound visualization of the needle tip by radiologists. He developed lid swelling the next day, and 3 days later at referral, the visual acuity in the left eye was no light perception. Funduscopy revealed central retinal artery occlusion and fluorescein angiography disclosed no perfusion at all in the left fundus, indicating concurrent posterior ciliary artery occlusion. The patient also showed mydriasis, blepharoptosis, and total external ophthalmoplegia on the left side. Magnetic resonance imaging demonstrated the swollen medial rectus muscle. In a month, blepharoptosis and ophthalmoplegia resolved but the visual acuity remained no light perception. Sclerosing therapy for facial hemangioma may develop a severe complication such as permanent visual loss.

  6. Blood vessel classification into arteries and veins in retinal images

    Science.gov (United States)

    Kondermann, Claudia; Kondermann, Daniel; Yan, Michelle

    2007-03-01

    The prevalence of diabetes is expected to increase dramatically in coming years; already today it accounts for a major proportion of the health care budget in many countries. Diabetic Retinopathy (DR), a micro vascular complication very often seen in diabetes patients, is the most common cause of visual loss in working age population of developed countries today. Since the possibility of slowing or even stopping the progress of this disease depends on the early detection of DR, an automatic analysis of fundus images would be of great help to the ophthalmologist due to the small size of the symptoms and the large number of patients. An important symptom for DR are abnormally wide veins leading to an unusually low ratio of the average diameter of arteries to veins (AVR). There are also other diseases like high blood pressure or diseases of the pancreas with one symptom being an abnormal AVR value. To determine it, a classification of vessels as arteries or veins is indispensable. As to our knowledge despite the importance there have only been two approaches to vessel classification yet. Therefore we propose an improved method. We compare two feature extraction methods and two classification methods based on support vector machines and neural networks. Given a hand-segmentation of vessels our approach achieves 95.32% correctly classified vessel pixels. This value decreases by 10% on average, if the result of a segmentation algorithm is used as basis for the classification.

  7. A case of central retinal artery occlusion following embolization procedure for juvenile nasopharyngeal angiofibroma

    Directory of Open Access Journals (Sweden)

    Ramezani Alireza

    2010-01-01

    Full Text Available A 23-year-old male patient with right nasal Juvenile Nasopharyngeal Angiofibroma (JNA developed Central Retinal Artery Occlusion (CRAO during embolization of the tumor using polyvinyl alcohol particles before endoscopic excision. Classic CRAO management was initiated by an ophthalmologist after 12 h. Retrospective evaluation of the angiograms revealed a tiny communication between the external carotid and ophthalmic arteries which had not been noticed before embolization. During endoscopic excision, the tumor was found to originate extraordinarily from midline structures. It was concluded that CRAO might be a rare complication of JNA embolization. Careful preoperative angiographic evaluations to detect communicating arteries and immediate ophthalmologic consultation in case of developing visual symptoms during the procedure are necessary.

  8. A case of Churg-Strauss syndrome and central retinal artery occlusion with good visual recovery

    Directory of Open Access Journals (Sweden)

    Yuki Kamata

    2013-01-01

    Full Text Available Here we report a case of Churg-Strauss syndrome (CSS and central retinal artery occlusion (CRAO, with good visual recovery. A 58-year-old Japanese man with CSS experienced acute painless loss of vision in his right eye. CRAO was diagnosed by fundoscopic findings (retinal whitening with a cherry-red spot. Steroid pulse therapy (methylprednisolone at 1 g daily for 3 days followed by combined treatment with prednisolone (30 mg/day and cyclophosphamide (150 mg/day was administered; his visual acuity recovered to 20/30 in 1 month, and no recurrence has occurred for 1 year. Steroid pulse therapy may be effective for CRAO in CSS patients.

  9. Cerebro-retinal ischemia after bilateral occlusion of internal carotid artery

    International Nuclear Information System (INIS)

    Six patients with occlusion of internal carotid arteries (ICAs) were prospectively followed during a mean period of 14 months. Prior to demonstration of occlusions, four patients suffered a mild stroke, and three isolated transient ischemic attacks (TIAs) or amaurosis fugax. All patients remained alive and with an unchanged functional ability. During follow-up, one patient suffered amaurosis fugax and TIAs followed by a mild stroke, three suffered isolated TIAs or amaurosis fugax, two suffered reversible cerebro-retinal ischemia of more than 24 hours, and one remained symptomfree. In three cases, delayed cerebro-retinal ischemia distal to one of the occluded ICAs was systematically triggered by orthostatic, cardiogenic or iatrogenic hypotension, and resolved after adequate medical treatment or restoration of a functional collateral circulation by endarterectomy of a tightly stenosed ipsilateral external carotid artery (ECA), suggesting hemodynamic phenomena. In three cases, micro-emboli originating from a stump or an ulcerated ipsilateral common carotid artery and migrating through well-developed ECA collateral channels explained delayed episodes of ipsilateral TIAs or amaurosis fugax, which disappeared in two cases after adequate anticoagulant therepy was introduced. Bilateral occlusion of ICA may be a relatively benign condition, if the patients are carefully controlled and treated. (orig.)

  10. A Case of Central Retinal Artery Occlusion after Chiropractic Manipulation of the Neck

    OpenAIRE

    Jang, Young-Jun; Chun, Jun-Woo; Lee, Seung-Woo; Kim, Ho-Chang

    2012-01-01

    Here we report a case of central retinal artery occlusion after chiropractic manipulation on the neck. A 49-year old man presented at the hospital because of sudden visual loss in his right eye after chiropractic neck manipulation. He had received chiropractic manipulation of the neck by a chiropractor eight days prior. When he first visited us, his best corrected visual acuity in his right eye was hand motion. A full ophthalmic examination was performed. There was cherry-red spot in the macu...

  11. VZV multifocal vasculopathy with ischemic optic neuropathy, acute retinal necrosis and temporal artery infection in the absence of zoster rash.

    Science.gov (United States)

    Mathias, Marc; Nagel, Maria A; Khmeleva, Nelly; Boyer, Philip J; Choe, Alexander; Durairaj, Vikram D; Bennett, Jeffrey L; Mandava, Naresh; Gilden, Don

    2013-02-15

    We describe a 54-year-old diabetic woman who developed ischemic optic neuropathy followed by acute retinal necrosis and multiple areas of focal venous beading. Vitreous fluid contained amplifiable VZV DNA but not HSV-1, CMV or toxoplasma DNA. The clinical presentation was remarkable for jaw claudication and intermittent scalp pain, prompting a temporal artery biopsy that was pathologically negative for giant cell arteritis, but notable for VZV antigen. The current case adds to the clinical spectrum of multifocal VZV vasculopathy. The development of acute VZV retinal necrosis after ischemic optic neuropathy supports the notion that vasculitis is an important additional mechanism in the development of VZV retinal injury. PMID:23312850

  12. Unilateral central retinal artery occlusion as the sole presenting sign of Susac syndrome in a young man: case report

    Directory of Open Access Journals (Sweden)

    Samira Luiza dos Apóstolos-Pereira

    2013-06-01

    Full Text Available We report the case of a 24-year-old man presenting with sudden visual loss in the left eye from a central retinal artery occlusion. An extensive clinical investigation revealed no etiology. Three weeks later, however, the patient developed hearing loss followed by encephalopathy and multiple branch retinal artery occlusions in the right eye. Fluorescein angiography confirmed retinal vascular occlusions with no sign of vasculitis. The neurological examination revealed a diffuse encephalopathy while the MRI scan disclosed several small areas of infarcts in the brain. Bilateral sensorineural hearing loss was confirmed on audiometry. The patient was diagnosed with Susac syndrome and treated with methylprednisolone and cyclophosphamide, resulting in slight improvement and stabilization. This case shows that Susac syndrome may be diagnosed late due to the absence at onset of one or more of the symptoms of the classic triad (encephalopathy, multiple branch retinal artery occlusions and hearing loss. This case also serves to emphasize that Susac syndrome should be considered in the differential diagnosis of central retinal artery occlusion, even in apparently healthy young men.

  13. Central retinal artery occlusion in a patient with ANCA-negative Churg-Strauss syndrome

    Directory of Open Access Journals (Sweden)

    Miyazaki M

    2012-07-01

    Full Text Available Yuji Kumano,1 Noriko Yoshida,2 Satoru Fukuyama,3 Masanori Miyazaki,2 Hiroshi Enaida,2 Takaaki Matsui11Ohshima Hospital of Ophthalmology, Fukuoka, 2Department of Ophthalmology, 3Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, JapanAbstract: Ocular involvement in Churg-Strauss syndrome is infrequent. We describe the case of a 54-year-old woman with eosinophilia and involvement of the respiratory tract, skin, and peripheral nervous system, fulfilling the American College of Rheumatology criteria for Churg-Strauss syndrome. The patient presented with acute, painless vision loss in her right eye. Central retinal artery occlusion (CRAO without accompanying retinal vasculitis was diagnosed by angiographic findings and funduscopic findings of retinal whitening with a cherry-red spot. Although her antineutrophil cytoplasmic antibody (ANCA status was negative, CRAO was thought to be an ocular manifestation of Churg-Strauss syndrome, and appropriate treatment was planned. She was treated with high-dose corticosteroids and anticoagulant therapy. Her macular edema improved, but visual recovery was poor. Specific therapy to alter inflammation, blood coagulation, and rheology reportedly plays an important role in ANCA-positive patients with Churg-Strauss syndrome who develop CRAO. Regardless of ANCA status, high-dose corticosteroids should be considered for CRAO in patients with Churg-Strauss syndrome, as discussed in this case.Keywords: CRAO, ANCA, Churg-Strauss syndrome

  14. A new imaging technique for retinal vessel oximetry: principles and first clinical results in patients with retinal arterial occlusion and diabetic retinopathy

    Science.gov (United States)

    Hammer, M.; Riemer, T.; Vilser, W.; Gehlert, S.; Schweitzer, D.

    2009-02-01

    The oxygen saturation of blood inside retinal vessels is an essential measure for the estimation of oxygen supply to the tissue as well as its oxygen consumption. In the current approach, the blood oxygenation is measured by a dual-wavelength technique. Using a fundus camera, equipped with a special dual wavelength transmission filter and a color CCD camera, two monochromatic fundus images at 548 nm and 610 nm were recorded simultaneously. The optical densities of retinal vessels for both wavelengths and their ratio, which is known to be proportional to the oxygen saturation, were calculated. From a health control population, mean arterial and venous oxygen saturations were measured of 98+/-10.1% and 65+/-11.7% with reproducibility of 2.52% and 3.25% respectively. In 10 patients with arterial occlusion, a reduction of the arterial oxygen saturation to 78 +/-17% (mean +/- standard deviation, branch arterial occlusion) and 91+/-11% (central arterial occlusion) respectively was found in the occluded vessel. After 5 days on pentoxifilin therapy, the arterial saturation increased to an average of 93+/-12% or 103 +/-6% respectively. In 70 eyes of 42 patients suffering from diabetic retinopathy, an increase of the venous oxygen saturation with the severity of the retinopathy was found (mild nonproliferative retinopathy: 68.4+/-8.2%, moderate non-proliferative retinopathy: 70.5+/-6.8%, severe non-proliferative retinopathy: 72.4+/-7.6%, proliferative retinopathy 75.7+/-8.3%) due to vessel shunting and diabetic changes of the permeability of vessel walls. These first clinical results demonstrate the ability of an accurate measurement of retinal vessel oxygenation with a very simple setup just requiring a special filter in the illumination path of a fundus camera and dedicated software.

  15. Atrial Fibrillation and Coronary Artery Disease as Risk Factors of Retinal Artery Occlusion: A Nationwide Population-Based Study

    Science.gov (United States)

    Yen, Ju-Chuan; Lin, Hsiu-Li; Hsu, Chia-An; Li, Yu-Chuan (Jack); Hsu, Min-Huei

    2015-01-01

    We use Taiwanese national health insurance research database (NHIRD) to investigate whether thrombolism (carotid artery disease (CAD) as a surrogate) or embolism (atrial fibrillation (AF) as a surrogate) plays roles in later retinal artery occlusion (RAO) development and examine their relative weights. The relative risks of RAO between AF and CAD patients and controls were compared by estimating the crude hazard ratio with logistic regression. Kaplan-Meier analysis was used to calculate the cumulative incidence rates of developing RAO, and a log-rank test was used to analyze the differences between the survival curves. Separate Cox proportional hazard regressions were done to compute the RAO-free rate after adjusting for possible confounding factors such as age and sex. The crude hazard ratios were 7.98 for the AF group and 5.27 for the CAD group, and the adjusted hazard ratios were 8.32 and 5.34 for the AF and CAD groups, respectively. The observation time with RAO-free was shorter for AF compared with CAD group (1490 versus 1819 days). AF and CAD were both risk factors for RAO with different hazard ratios. To tackle both AF and CAD is crucial for curbing RAO.

  16. Central retinal artery occlusion following laser treatment for ocular ischemic aortic arch syndrome

    Directory of Open Access Journals (Sweden)

    Shah, Payal J.

    2015-12-01

    Full Text Available Objective: Ocular ischemic syndrome is a rare blinding condition generally caused by disease of the carotid artery. We describe a 69-year-old female with a 50 pack-year smoking history with aortic arch syndrome causing bilateral ocular ischemic syndrome. Methods: The patient presented with progressive visual loss and temple pain. Slit lamp biomicroscopy revealed bilateral iris neovascularization. This finding prompted a cardiovascular work up. Panretinal photocoagulation with retrobulbar block was performed in the right eye. Results: A temporal artery biopsy was negative. The carotid duplex sound showed only a 1–39% stenosis. MRA revealed a more proximal occlusion of the aortic branch for which she underwent subclavian carotid bypass surgery. At the one month follow up, the right eye suffered profound vision loss secondary to a central retinal artery occlusion. Conclusion: Ocular neovascularization may be one of the clinical manifestations of aortic arch syndrome. This case also illustrates the limitations of relying solely on carotid duplex ultrasound testing. We caution against overly aggressive panretinal photocoagulation utilizing retrobulbar anesthesia.

  17. Combined central retinal artery and vein occlusion secondary to systemic non-Hodgkin?s lymphoma

    Directory of Open Access Journals (Sweden)

    Shukla Dhananjay

    2006-01-01

    Full Text Available We report a rare case of low-grade systemic B-cell non-Hodgkin?s lymphoma (NHL causing central retinal artery and vein occlusion, which was the only manifestation of disease recurrence. A young man with resolved systemic NHL underwent fluorescein angiography, magnetic resonance imaging and computed tomography to investigate a severe unilateral visual loss. A combined vascular occlusion was observed in the right eye. Neuroimaging detected optic nerve infiltration; but no systemic/ central nervous system involvement was observed. The patient was treated with high-doses of corticosteroids and optic nerve irradiation. The optic neuropathy and vascular occlusion were resistant to treatment. The subsequent neovascular glaucoma was treated by panretinal photocoagulation, which relieved the pain, but vision was not recovered. No further recurrence was observed over the following year.

  18. Retinal protective effects of topically administered agmatine on ischemic ocular injury caused by transient occlusion of the ophthalmic artery

    Scientific Electronic Library Online (English)

    S., Hong; H., Hara; M., Shimazawa; K., Hyakkoku; C.Y., Kim; G.J., Seong.

    2012-03-01

    Full Text Available Agmatine, an endogenous polyamine and putative neuromodulator, is known to have neuroprotective effects on various neurons in the central nervous system. We determined whether or not topically administered agmatine could reduce ischemic retinal injury. Transient ocular ischemia was achieved by intra [...] luminal occlusion of the middle cerebral artery of ddY mice (30-35 g) for 2 h, which is known to also induce occlusion of the ophthalmic artery. In the agmatine group (N = 6), a 1.0 mM agmatine-containing ophthalmic solution was administered four times daily for 2 weeks before occlusion. In the control group (N = 6), a 0.1% hyaluronic acid ophthalmic solution was instilled at the same times. At 22 h after reperfusion, the eyeballs were enucleated and the retinal sections were stained by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL). Transient ocular ischemia induced apoptosis of retinal cells in the entire retinal layer, and topically administered agmatine can significantly reduce this ischemic retinal injury. The proportion of apoptotic cells was definitely decreased (P

  19. Relationship between Retinal Vascular Caliber and Coronary Artery Disease in Patients with Non-Alcoholic Fatty Liver Disease (NAFLD

    Directory of Open Access Journals (Sweden)

    Marmor Alon

    2013-08-01

    Full Text Available Objective: To evaluate the relationship between retinal vascular caliber and cardiovascular disease in non-alcoholic fatty liver disease (NAFLD patients without diabetes and hypertension. Methods: Intention to treat study of individuals who underwent cardiac computed tomography (CT during a two year period. Coronary artery disease (CAD was defined as stenosis of >50% in at least one major coronary artery. Liver and spleen density were measured by abdominal (CT; intima-media thickness (IMT by Doppler ultrasound; retinal artery and vein diameter by colored-retinal angiography; and metabolic syndrome by ATP III guidelines. Serum biomarkers of insulin resistance, inflammation, and oxidant-antioxidant status were assessed. Results: Compared with 22 gender and age matched controls, the 29 NAFLD patients showed higher prevalence of coronary plaques (70% vs. 30%, p < 0.001, higher prevalence of coronary stenosis (30% vs. 15%, p < 0.001, lower retinal arteriole-to-venule ratio (AVR (0.66 ± 0.06 vs. 0.71 ± 0.02, p < 0.01, higher IMT (0.98 ± 0.3 vs. 0.83 ± 0.1, p < 0.04, higher carotid plaques (60% vs. 40%, p < 0.001, higher homeostasis model assessment of insulin resistance (HOMA (4.0 ± 3.4 vs. 2.0 ± 1.0, p < 0.005, and higher triglyceride levels (200 ± 80 vs. 150 ± 60, p < 0.005 than controls. Multivariate analysis showed fatty liver (OR 2.5; p < 0.01, IMT (OR 2.3 p < 0.001, and retinal AVR ratio (OR 1.5, p < 0.01 to be strongly associated with CAD independent of metabolic syndrome (OR 1.2, p < 0.05. Conclusions: Patients with smaller retinal AVR (<0.7 are likely to be at increased risk for CAD and carotid atherosclerosis in patients with NAFLD even without hypertension or diabetes.

  20. Mitogen-activated protein kinases in the porcine retinal arteries and neuroretina following retinal ischemia-reperfusion

    DEFF Research Database (Denmark)

    Gesslein, Bodil; Håkansson, Gisela; Carpio, Ronald; Gustafsson, Lotta; Perez, Maria-Thereza; Malmsjö, Malin

    2010-01-01

    The aim of the present study was to examine changes in the expression of intracellular signal-transduction pathways, specifically mitogen-activated protein kinases, following retinal ischemia-reperfusion....

  1. Central Retinal Artery Occlusion- A rare complication of oral contraceptive pills

    Directory of Open Access Journals (Sweden)

    Nidhi Pancholi

    2013-07-01

    Full Text Available Aim: To propose a hypothesis of causal association between central retinal artery occlusion (CRAO and oral contraceptive pills (OCPCase Summary:A case report-A 22 yr old, female presented with sudden painless loss of vision in OS [Right Eye] for 1 day. VA [Visual Activity] in OS was PL PR [Perception of Light and Projection of Rays] Faulty with RAPD [Relative Afferent Papillary Defect] with normal for fifteen minutes, given five hundred mg of acetazolamide orally stat, 0.4 ml of anterior chamber paracentesis done, 5400 IU LMW [Low Molecular Weight] heparin given SC[Subcutaneous] with carbogen inhalation. Retrospectively she was on oral contraceptives(Mala D for 1 month. She was not hypertensive or diabetic with normal blood, coagulation profile & carotid Doppler. She was evaluated by an intern to find the cause of coagulation disorder and was found to be normal. On first day FFA [Fundus Florescien Angiography] showed no blockage with normal cilioretinal artery perfusion established. Visual fields after one week showed central tubular vision and OCT [Ocular Coherent Tomography] showed normal fovea. After 2 weeks vision was 20/80 with persistent RAPD papilla macular bundle being perfused.

  2. Acute Central Retinal Artery Occlusion Associated with Intraocular Silicone Oil Tamponade

    Directory of Open Access Journals (Sweden)

    Mehmet Yasin Teke

    2012-05-01

    Full Text Available Many systemic and ocular factors may cause acute central retinal artery occlusion (CRAO. Herein, we aimed to describe a case of CRAO due to intraocular silicone oil (SO tamponade. To the best of our knowledge, a case like our has not been reported previously. A 58-yearold male patient had undergone combined pars plana vitrectomy-lensectomy and intraocular SO for lens luxation and vitreus hemorrhage associated with a blunt ocular trauma in his right eye. Two weeks after the surgery, he presented with acute vision loss in the same eye. He was diagnosed with acute CRAO and it should be related with mechanical press or raised intraocular pressure (IOP associated with SO. He was treated by partial removal of SO immediately. In spite of the regression of retina edema, his visual acuity did not improve due to optic atrophy. SO may cause CRAO due to raised IOP and/or its mechanical pressure and this complication must be kept in mind. (Turk J Oph thal mol 2012; 42: 238-40

  3. HIGH DIVISION ABDOMINAL AORTA WITH TORTUOUS ILIAC ARTERIES

    OpenAIRE

    Pradeep Kumar H Murudkar; Ravindra Kumar Boddeti

    2013-01-01

    Abdominal Aorta is considered as principle arteryof the abdominal cavity through which thevarious branches will be arises to supply differentparts of the gut according to their developmentalrelationship.As per the standard Anatomical text bookdescription, abdominal aorta begins at themedian, aortic hiatus of the diaphragm, anteriorto the inferior border of the 12th thoracicvertebra and the thoracolumbar intervertebraldisc. It descends anterior to the lumbarvertebrae to end at the lower border...

  4. HIGH DIVISION ABDOMINAL AORTA WITH TORTUOUS ILIAC ARTERIES

    Directory of Open Access Journals (Sweden)

    Pradeep Kumar H Murudkar

    2013-05-01

    Full Text Available Abdominal Aorta is considered as principle arteryof the abdominal cavity through which thevarious branches will be arises to supply differentparts of the gut according to their developmentalrelationship.As per the standard Anatomical text bookdescription, abdominal aorta begins at themedian, aortic hiatus of the diaphragm, anteriorto the inferior border of the 12th thoracicvertebra and the thoracolumbar intervertebraldisc. It descends anterior to the lumbarvertebrae to end at the lower border of thefourth lumbar vertebra, a little to the left of themidline, by dividing into two common iliacarteries.

  5. Central retinal artery occlusion and non-arteritic anterior ischemic optic neuropathy associated with an overlap syndrome: a case report

    Directory of Open Access Journals (Sweden)

    Lima Verônica C

    2008-12-01

    Full Text Available Abstract Introduction An "overlap syndrome" is defined as the sequential appearance over time of two or more risk factors for glaucomatous damage. The appearance of a new risk factor can alter the course and prognosis of previously stable disease. Exfoliation syndrome is a leading cause of glaucoma and is associated with vascular disease. We report a case of central retinal artery occlusion and non-arteritic anterior ischemic optic neuropathy in a patient with overlap syndrome. Case presentation An 87-year-old woman with longstanding stable primary open-angle glaucoma developed bilateral exfoliation syndrome, after which her intraocular pressure became uncontrolled and her glaucomatous damage progressed rapidly. She also developed ischemic arterial events in both eyes. Conclusion The case presented here shows that overlap syndromes can lead to rapid, irreversible vision impairment. To the best of our knowledge, this is the first reported case of central retinal artery occlusion and non-arteritic anterior ischemic optic neuropathy in a patient with overlap syndrome.

  6. Obstrução arterial retiniana periférica associada com hiper-homocisteinemia: relato de caso Peripheral retinal arterial obstruction associated with hyperhomocysteinemia: case report

    Directory of Open Access Journals (Sweden)

    Alexandre Kazuo Misawa

    2008-10-01

    Full Text Available A hiperhomocisteinemia é fator de risco para fenômenos trombo-embólicos retinianos associados a quadro de oclusão vascular venosa e arterial. Descrevemos um paciente com obstrução arterial retiniana periférica, sem sinais de vasculite ativa, associada a proliferação de neovasos com tração vítreo-retiniana e hemorragia vítrea recidivante. O alto nível sérico de homocisteína decorrente de deficiência de vitamina B12 e ácido fólico, sem outras alterações na cascata da coagulação, inclusive com a pesquisa do fator V de Leiden, sugere que a hiper-homocisteinemia esteja diretamente ligada como fator causal deste quadro clínico. Embora apresentasse PPD elevado, o diagnóstico diferencial mais importante de doença de Eales foi menos considerado por ser diagnóstico de exclusão. O controle do quadro clínico foi feito com suplemento de vitaminas (B12 e ácido fólico e fotocoagulação retiniana periférica. A homocisteína plasmática total deve ser dosada em pacientes com obstrução vascular retiniana, já que a hiper-homocisteinemia é fator de risco modificável e de fácil tratamento por meio de dieta ou suplementação vitamínica.Hyperhomocysteinemia is a risk factor for thromboembolic events of the retina associated with vascular venous or arterial occlusion. We describe a patient with occlusion of the peripheral arteriolar network without active vasculitis, associated with neovascular proliferation, peripheral vitreous-retinal traction and relapsing vitreous hemorrhage. The high serum homocysteine level resulting from vitamin B12 and folic acid deficiency, without further changes in the coagulation cascade including the test for Leiden's Factor V, indicates hyperhomocysteinemia as a direct causal factor in this clinical condition. Despite a high PPD, Eales Disease, a major differential diagnosis, was not fully considered, since it is established by exclusion. The patient was treated with photocoagulation and vitamin supplements and the condition was successfully controlled. Patients with retinal vascular obstruction should have their total plasma homocysteine levels measured, since this modifiable risk factor can be easily treated with dietary approaches including vitamin supplementation.

  7. Accurate 3D reconstruction of tortuous coronary vessels using biplane angiography and intravascular ultrasound

    Science.gov (United States)

    Prause, Guido P. M.; DeJong, Steven C.; McKay, Charles R.; Sonka, Milan

    1997-05-01

    At present, 3D reconstructions of coronary vessels are generated from intravascular ultrasound (IVUS) pullback sequences by stacking up ECG-gated segmented IVUS frames. Since this approach results in straight vessel reconstructions, it clearly fails in tortuous coronary arteries. This shortcoming may be overcome by data fusion with biplane angiography. The 3D course of the vessel is first derived from angiograms and then combined with segmented IVUS images in order to obtain a spatially correct and anatomically complete vessel reconstruction. In this paper, different approaches to two problems associated with the data fusion method are discussed: the definition of the pullback path and the estimation of IVUS catheter twist during pullback. A procedure for image acquisition, segmentation, mapping, and interpolation is proposed that has been designed with respect to its clinical applicability. In vitro validations of our previously reported algorithm for analytic catheter twist quantification is presented along with data fusion results of coronary arteries in cadaveric pig hearts.

  8. Internal carotid artery pseudo occlusion with embolic cerebral ischemia and low flow in the central retinal artery: a diagnostic challenge

    Directory of Open Access Journals (Sweden)

    Christoph Roehrer

    2011-08-01

    Full Text Available We present a rare case of internal carotid artery pseudoocclusion (ICAPO in a 60-yearold male Caucasian patient who experienced a reversible sudden loss of vision of the right eye for 10 min followed by recurrent blurring of vision as well as dysarthria and numbness in the left face. The referring ophthalmologist admitted the patient for suspicious occlusion of the internal carotid artery causing anterior ischemic optic neuropathy (AION.

  9. Multifocal central serous chorioretinopathy with photoreceptor-retinal pigment epithelium diastasis in heritable pulmonary arterial hypertension

    DEFF Research Database (Denmark)

    Li, Xiao Qiang; Pryds, Anders; Carlsen, Jørn; Larsen, Michael

    2015-01-01

    PURPOSE: To report atypical central serous chorioretinopathy and choroidal thickening in a patient with heritable pulmonary arterial hypertension. METHODS: A 40-year-old man with heritable pulmonary arterial hypertension presented with blurred vision in his left eye and was followed up for 1 year...... chorioretinopathy and choroidal thickening that responded to treatment of pulmonary arterial hypertension suggest a pathophysiological link between pulmonary arterial hypertension and central serous chorioretinopathy, perhaps mediated by choroidal venous stasis....... choroidal vessels were seen in the patient's symptomatic left eye. After treatment for pulmonary hypertension, the serous detachments disappeared and choroidal thickness gradually decreased over a period of 4 weeks and remained unchanged at 13 months of follow-up. CONCLUSION: Central serous...

  10. Obstrução arterial retiniana periférica associada com hiper-homocisteinemia: relato de caso / Peripheral retinal arterial obstruction associated with hyperhomocysteinemia: case report

    Scientific Electronic Library Online (English)

    Alexandre Kazuo, Misawa; Hisashi, Suzuki; Otacílio de Oliveira, Maia Júnior; Maria Teresa Brizzi Chizzotti, Bonanomi; Carlos Sérgio Nascimento de, Melo.

    2008-10-01

    Full Text Available A hiperhomocisteinemia é fator de risco para fenômenos trombo-embólicos retinianos associados a quadro de oclusão vascular venosa e arterial. Descrevemos um paciente com obstrução arterial retiniana periférica, sem sinais de vasculite ativa, associada a proliferação de neovasos com tração vítreo-ret [...] iniana e hemorragia vítrea recidivante. O alto nível sérico de homocisteína decorrente de deficiência de vitamina B12 e ácido fólico, sem outras alterações na cascata da coagulação, inclusive com a pesquisa do fator V de Leiden, sugere que a hiper-homocisteinemia esteja diretamente ligada como fator causal deste quadro clínico. Embora apresentasse PPD elevado, o diagnóstico diferencial mais importante de doença de Eales foi menos considerado por ser diagnóstico de exclusão. O controle do quadro clínico foi feito com suplemento de vitaminas (B12 e ácido fólico) e fotocoagulação retiniana periférica. A homocisteína plasmática total deve ser dosada em pacientes com obstrução vascular retiniana, já que a hiper-homocisteinemia é fator de risco modificável e de fácil tratamento por meio de dieta ou suplementação vitamínica. Abstract in english Hyperhomocysteinemia is a risk factor for thromboembolic events of the retina associated with vascular venous or arterial occlusion. We describe a patient with occlusion of the peripheral arteriolar network without active vasculitis, associated with neovascular proliferation, peripheral vitreous-ret [...] inal traction and relapsing vitreous hemorrhage. The high serum homocysteine level resulting from vitamin B12 and folic acid deficiency, without further changes in the coagulation cascade including the test for Leiden's Factor V, indicates hyperhomocysteinemia as a direct causal factor in this clinical condition. Despite a high PPD, Eales Disease, a major differential diagnosis, was not fully considered, since it is established by exclusion. The patient was treated with photocoagulation and vitamin supplements and the condition was successfully controlled. Patients with retinal vascular obstruction should have their total plasma homocysteine levels measured, since this modifiable risk factor can be easily treated with dietary approaches including vitamin supplementation.

  11. Efeito da tibolona sobre parâmetros doplervelocimétricos das artérias oftálmica e retiniana / Tibolone's effect on retinal and ophthalmic arteries flowmetry

    Scientific Electronic Library Online (English)

    Marco Aurélio Martins de, Souza; Selmo, Geber.

    2008-11-01

    Full Text Available OBJETIVO: avaliar o efeito do uso da tibolona sobre os parâmetros doplervelocimétricos das artérias oftálmica e retiniana. MÉTODOS: realizou-se ensaio clínico, prospectivo, longitudinal, aleatorizado, controlado com placebo, duplo-cego, no qual dentre 100 mulheres na menopausa, 50 usaram o princípio [...] ativo tibolona 2,5 mg (Grupo Tib) e 50, o placebo para formar o grupo controle (Grupo Plac). No Grupo Tib, das 50 mulheres que iniciaram o estudo, 44 retornaram após 84 dias para a finalização dos exames. No Grupo Plac retornaram 47 delas. As artérias oftálmica e retiniana foram estudadas, determinando-se o índice de resistência (IR), índice de pulsatilidade (IP) e relação sístole/diástole (S/D). As aferições foram feitas antes e 84 dias após a medicação. Utilizou-se o teste t de Student para amostras independentes na comparação das medianas entre os grupos e para amostras dependentes na comparação entre as medianas dentro do mesmo grupo. RESULTADOS: as características das mulheres nos dois grupos foram semelhantes em relação à idade, ao tempo de menopausa, ao índice de massa corporal, à pressão arterial, à paridade e à freqüência cardíaca. O Grupo Tib apresentou as seguintes medianas: IR(pré)=0,71±0,05, IR(pós)=0,72±0,08 (p=0,43); IP(pré)=1,29±0,22, IP(pós)=1,30±0,25 (p=0,4) e SD(pré)=3,49±0,77, SD(pós)=3,65±0,94 (p=0,32). Na artéria retiniana foram obtidas as seguintes medianas na artéria oftálmica: IR(pré)=0,67±0,09, IR(pós)=0,69±0,10 (p=0,7); IP(pré)=1,20±0,29, IP(pós)=1,22±0,3 (p=0,2) e SD(pré)=3,29±0,95, SD(pós)=3,30±1,07 (p=0,3). Os grupos tibolona e controle não apresentaram diferenças significantes nos índices quando avaliados ao final do estudo. CONCLUSÕES: a tibolona, na dose de 2,5 mg, não apresenta efeitos sobre os índices doppler das artérias oftálmica e retiniana. Abstract in english PURPOSE: to evaluate the effect of tibolone use on dopplervelocimetric parameters of ophthalmic and retinal arteries. METHODS: clinical, prospective, longitudinal, randomized, placebo-controlled, triple-blind study, in which among 100 menopausal women, 50 have used 2.5 mg of the active principle tib [...] olone (Tib Group) and 50, placebo as a means to form the control-group (Plac Group). In the Tib Group, 44 of the 50 women returned after 84 days to finish the exams, and in the Plac Group, 47. The ophthalmic and retinal arteries were studied to determine the resistance index (RI), the pulsatility index (PI) and the systole/diastole ratio (S/D). Assessments have been done before and 84 days after medication. The t-Student test has been used for the comparison of means between the groups in independent samples, as well as for within-group comparisons in dependent samples. RESULTS: in both groups, the women's characteristics were similar in age, menopause duration, body mass index, arterial blood pressure, deliveries and cardiac rate. The Tib Group presented the following values in the ophthalmic artery: RI(pre)=0.71±0.05, RI(post)0.72±0.08 (p=0.43); PI(pre)=1.29±0.22, PI(post)=1.30±0.25 (p=0.4) and S/D(pre)=3.49±0.77, SD(post)=3.65±0.94 (p=0.32). In the retinal artery, the following values have been found: RI(pre)=0.67±0.09, RI(post)=0.69±0.10 (p=0.7); PI(pre)=1.20±0.29, PI(post)=1.22±0.3 (p=0.2) and SD(pre)=3.29±0.95, SD(post)=3.30±1.07 (p=0.3). Also, the tibolone and control groups did not show any significant difference in regard to the above indexes in the end of the study. CONCLUSIONS: the 2.5 mg dose of tibolone had no effect on the Doppler velocimetry indexes of the ophthalmic and retinal arteries.

  12. Doplervelocimetria das artérias oftálmica e central da retina em gestantes normais Dopplervelocimetry of ophthalmic and central retinal arteries in normal pregnancies

    Directory of Open Access Journals (Sweden)

    Angélica Lemos Debs Diniz

    2005-04-01

    Full Text Available OBJETIVOS: avaliar os padrões dos índices doplervelocimétricos das artérias oftálmica e central da retina durante o segundo e terceiro trimestres da gestação normal e comparar os valores obtidos do olho direito e esquerdo das gestantes. MÉTODOS: estudo transversal no qual se avaliaram seis índices doplervelocimétricos das artérias central da retina e oftálmica em 51 gestantes normais, com idades gestacionais entre a 20ª e a 38ª semana. As variáveis analisadas foram os índices de resistência e pulsatilidade (IR, IP, os picos de velocidade sistólica e diastólica (PVS, PVD e a razão entre picos de velocidade (RPV. A análise dos índices doplervelocimétricos dos olhos direito e esquerdo foi realizada utilizando-se a mediana dos valores. Para a comparação dos valores dos índices entre os dois olhos das gestantes, utilizou-se o teste t de Student para dados pareados. A associação entre a idade gestacional e os índices foi testada empregando-se o coeficiente de correlação linear de Pearson. Adotou-se o nível de significância de 5% para os testes estatísticos. RESULTADOS: a mediana dos índices doplervelocimétricos das artérias oftálmica e central da retina foram, respectivamente: IP=1,83; IR=0,78; PVS=34,20; PVD=6,80; RPV=0,48 e IP=1,34; IR=0,70; PVS=7,40; PVD=2,10. Não houve diferenças na análise comparativa dos índices doplervelocimétricos entre os olhos direito e esquerdo das gestantes normais. O coeficiente de correlação linear entre a idade gestacional e os índices de ambas as artérias não mostrou diferença significante durante a gestação normal. CONCLUSÃO: é factível a análise unilateral dos índices doplervelocimétricos das artérias oftálmica e central da retina no estudo de doenças maternas sistêmicas. Não há mudança significativa dos índices doplervelocimétricos das artérias oftálmica e central da retina ao longo da gestação normal entre a 20ª e a 38ª semana.PURPOSE: to evaluate ophthalmic and retinal central artery Doppler indices during the second and third trimesters of normal pregnancy and to compare the right with left eye Doppler indices of normotensive women. METHODS: a cross-sectional study which evaluated central retinal and ophthalmic artery Doppler velocimetry values of 51 normal pregnant women, in the 20th to 38th week of gestation. The following values were analyzed: pulsatility and resistance indexes (PI, RI, peak systolic and end-diastolic flow velocity (PSV, EDFV and peak velocity ratio (PVR. The Doppler indices in the right and left eyes were studied by the median. The paired Student's t test was used to confront the right and left eye values and the Pearson linear correlation analysis was performed to study the value changes throughout the gestation, with the level of significance set at 5%. RESULTS: Doppler velocimetry indices of ophthalmic and central retinal arteries (median values were, respectively: PI=1.83; RI=0.78; PSV=34.20; EDFV=6.80; PVR=0.48 and PI=1.34; RI=0.70; PSV=7.40; EDFV=2.10. There was no significant difference between the right and left side Doppler values. Linear correlation analysis showed no association between the arterial values and pregnancy age. CONCLUSION: the unilateral analysis of ophthalmic and central retinal artery Doppler velocimetry values can be used in systemic maternal disease. There is no significant change in ophthalmic and central retinal artery Doppler velocimetry values throughout normal pregnancy.

  13. Doplervelocimetria das artérias oftálmica e central da retina em gestantes normais / Dopplervelocimetry of ophthalmic and central retinal arteries in normal pregnancies

    Scientific Electronic Library Online (English)

    Angélica Lemos Debs, Diniz; Antonio Fernandes, Moron; Maria Célia dos, Santos; Nelson, Sass; Claudio Rodrigues, Pires.

    2005-04-01

    Full Text Available OBJETIVOS: avaliar os padrões dos índices doplervelocimétricos das artérias oftálmica e central da retina durante o segundo e terceiro trimestres da gestação normal e comparar os valores obtidos do olho direito e esquerdo das gestantes. MÉTODOS: estudo transversal no qual se avaliaram seis índices d [...] oplervelocimétricos das artérias central da retina e oftálmica em 51 gestantes normais, com idades gestacionais entre a 20ª e a 38ª semana. As variáveis analisadas foram os índices de resistência e pulsatilidade (IR, IP), os picos de velocidade sistólica e diastólica (PVS, PVD) e a razão entre picos de velocidade (RPV). A análise dos índices doplervelocimétricos dos olhos direito e esquerdo foi realizada utilizando-se a mediana dos valores. Para a comparação dos valores dos índices entre os dois olhos das gestantes, utilizou-se o teste t de Student para dados pareados. A associação entre a idade gestacional e os índices foi testada empregando-se o coeficiente de correlação linear de Pearson. Adotou-se o nível de significância de 5% para os testes estatísticos. RESULTADOS: a mediana dos índices doplervelocimétricos das artérias oftálmica e central da retina foram, respectivamente: IP=1,83; IR=0,78; PVS=34,20; PVD=6,80; RPV=0,48 e IP=1,34; IR=0,70; PVS=7,40; PVD=2,10. Não houve diferenças na análise comparativa dos índices doplervelocimétricos entre os olhos direito e esquerdo das gestantes normais. O coeficiente de correlação linear entre a idade gestacional e os índices de ambas as artérias não mostrou diferença significante durante a gestação normal. CONCLUSÃO: é factível a análise unilateral dos índices doplervelocimétricos das artérias oftálmica e central da retina no estudo de doenças maternas sistêmicas. Não há mudança significativa dos índices doplervelocimétricos das artérias oftálmica e central da retina ao longo da gestação normal entre a 20ª e a 38ª semana. Abstract in english PURPOSE: to evaluate ophthalmic and retinal central artery Doppler indices during the second and third trimesters of normal pregnancy and to compare the right with left eye Doppler indices of normotensive women. METHODS: a cross-sectional study which evaluated central retinal and ophthalmic artery D [...] oppler velocimetry values of 51 normal pregnant women, in the 20th to 38th week of gestation. The following values were analyzed: pulsatility and resistance indexes (PI, RI), peak systolic and end-diastolic flow velocity (PSV, EDFV) and peak velocity ratio (PVR). The Doppler indices in the right and left eyes were studied by the median. The paired Student's t test was used to confront the right and left eye values and the Pearson linear correlation analysis was performed to study the value changes throughout the gestation, with the level of significance set at 5%. RESULTS: Doppler velocimetry indices of ophthalmic and central retinal arteries (median values) were, respectively: PI=1.83; RI=0.78; PSV=34.20; EDFV=6.80; PVR=0.48 and PI=1.34; RI=0.70; PSV=7.40; EDFV=2.10. There was no significant difference between the right and left side Doppler values. Linear correlation analysis showed no association between the arterial values and pregnancy age. CONCLUSION: the unilateral analysis of ophthalmic and central retinal artery Doppler velocimetry values can be used in systemic maternal disease. There is no significant change in ophthalmic and central retinal artery Doppler velocimetry values throughout normal pregnancy.

  14. AUTOMATIC RETINAL VESSEL TORTUOSITY MEASUREMENT

    OpenAIRE

    Nidhal Khdhair El Abbadi; Enas Hamood Al Saadi

    2013-01-01

    Retinal vascular vessels have the role to indicate the retinal diseases and for systematic diseases when there are any abnormalities in retinal vascular pattern. A characteristic of the vascular pattern that is appreciated by clinicians is vascular tortuosity, i.e., how curved or kinked a blood vessel, either vein or artery, appears along its course. In this study we suggest a novel mask filter to track the blood vessel along its course and measuring the blood vessels tortuosity over the enti...

  15. Effects of elastin degradation and surrounding matrix support on artery stability

    OpenAIRE

    Lee, Avione Y.; Han, Boyang; Lamm, Shawn D.; Fierro, Cesar A.; Han, Hai-Chao

    2011-01-01

    Tortuous arteries are often associated with aging, hypertension, atherosclerosis, and degenerative vascular diseases, but the mechanisms are poorly understood. Our recent theoretical analysis suggested that mechanical instability (buckling) may lead to tortuous blood vessels. The objectives of this study were to determine the critical pressure of artery buckling and the effects of elastin degradation and surrounding matrix support on the mechanical stability of arteries. The mechanical proper...

  16. An isolated left subclavian artery supplied by a collateral artery from the abdominal aorta

    Energy Technology Data Exchange (ETDEWEB)

    Ming, Zhu; Qian, Wang [Shanghai Jiaotong University School of Medicine, Department of Radiology, Shanghai Children' s Medical Center, Shanghai (China)

    2009-08-15

    An isolated left subclavian artery is a rare anomaly. We report a 9-month-old boy with an isolated left subclavian artery associated with tetralogy of Fallot and the right aortic arch. MRI and angiography show that the blood supply through the left subclavian artery was maintained by a large tortuous collateral artery from the abdominal aorta. This type of collateral artery structure is unique. (orig.)

  17. Retinal vascular oximetry during ranibizumab treatment of central retinal vein occlusion

    DEFF Research Database (Denmark)

    Traustason, Sindri; la Cour, Morten; Larsen, Michael

    2014-01-01

    PURPOSE: To investigate the effect of intravitreal injections of the vascular endothelial growth factor inhibitor ranibizumab on retinal oxygenation in patients with central retinal vein occlusion (CRVO). METHODS: Retinal oxygen saturation in patients with CRVO was analysed using the Oxymap Retinal...... Oximeter P3, before and during 6?months of treatment with intravitreal injections of ranibizumab. RESULTS: At presentation, retinal venous oxygen saturation was lower in eyes with CRVO than in the healthy fellow eyes (32±13% vs 59±10%, respectively, p=0.001) whereas retinal arterial saturation was higher.......012), while no significant change was found in arterial saturation (p=0.24). CONCLUSIONS: Retinal venous oxygen saturation was markedly reduced in untreated CRVO and was roughly halfway normalised during intravitreal ranibizumab treatment. Retinal artery oxygen saturation was not reduced in CRVO. TRIAL...

  18. Mechanical Buckling of Artery under Pulsatile Pressure

    OpenAIRE

    Liu, Qin; Han, Hai-Chao

    2012-01-01

    Tortuosity that often occurs in carotid and other arteries has been shown to be associated with high blood pressure, atherosclerosis, and other diseases. However the mechanisms of tortuosity development are not clear. Our previous studies have suggested that arteries buckling could be a possible mechanism for the initiation of tortuous shape but artery buckling under pulsatile flow condition has not been fully studied. The objectives of this study were to determine the artery critical bucklin...

  19. Oclusão artério-venosa da retina após bloqueio retrobulbar: relato de dois casos / Combined central retinal vein and artery occlusion after retrobulbar anesthesia: report of two cases

    Scientific Electronic Library Online (English)

    Rogil José de Almeida, Torres; Andréa, Luchini; Wilma, Weis; Paulo Roberto, Frecceiro; Marcelo, Casella.

    2005-04-01

    Full Text Available São descritos dois casos de oclusão artério-venosa da retina após cirurgia intra-ocular. As duas pacientes foram submetidas à anestesia peribulbar. Devido à sensação dolorosa e à mobilidade ocular foi necessário a realização de bloqueio retrobulbar. Ao final da cirurgia, ambas receberam injeção subc [...] onjuntival de gentamicina associada à dexametasona. No primeiro dia pós-cirúrgico as pacientes apresentaram arreflexia pupilar e acuidade visual de percepção luminosa, sendo referidas para nosso serviço. A confirmação do diagnóstico de oclusão vascular retiniana mista foi feito por meio do exame de retinografia fluorescente. As pacientes não manifestaram, em nenhum momento, alterações neurológicas, porém a perda visual foi grave e permanente. Por meio da descrição cirúrgica, da história clínica e dos achados oftalmoscópicos e angiográficos discutem-se as possíveis causas desta grave lesão vascular retiniana, dando ênfase à presumida injeção de anestésico na bainha do nervo óptico durante o bloqueio retrobulbar. Ao mesmo tempo, abordam-se medidas preventivas para evitar tal complicação. Abstract in english Two cases of combined central retinal artery and vein occlusion after intraocular surgery are described. Both patients were submitted to peribulbar anesthesia. Due to the painful sensation and ocular mobility retrobulbar anesthesia was necessary. At the end of the surgery both patients received a su [...] bconjunctival injection of gentamicin associated with dexamethasone. On the very first day after the surgery the two patients showed pupillary areflexia and visual acuity of luminous perception when they were referred to our service. The confirmation of the diagnosis of combined vascular occlusion of the retina was obtained by fluorescein angiography test. The two patients never showed, any neurological alteration. However visual loss was severe and permanent. By means of surgical description, clinical history, fundus photography and fluorescein angiography we are able to discuss the possible causes of this severe retinal vascular injury emphasizing the presumed anesthesic injection that was given into the optical nerve during retrobulbar anesthesia. At the same time we discuss preventive measures to avoid such problem.

  20. Retinal detachment

    OpenAIRE

    Fraser, Scott; Steel, David

    2010-01-01

    Rhegmatogenous retinal detachment (RRD) is the most common form of retinal detachment, where a retinal "break" allows the ingress of fluid from the vitreous cavity to the subretinal space, resulting in retinal separation. It occurs in about 1 in 10,000 people a year. This review considers only acute progressive RRD.

  1. Retinal detachment

    OpenAIRE

    Fraser, Scott; Steel, David

    2009-01-01

    Rhegmatogenous retinal detachment (RRD) is the most common form of retinal detachment, where a retinal "break" allows the ingress of fluid from the vitreous cavity to the subretinal space, resulting in retinal separation. It occurs in about 1 in 10,000 people a year. This review considers only acute progressive RRD.

  2. Intravital Video Microscopy Measurements of Retinal Blood Flow in Mice

    OpenAIRE

    Norman R. Harris; Watts, Megan N.; Leskova, Wendy

    2013-01-01

    Alterations in retinal blood flow can contribute to, or be a consequence of, ocular disease and visual dysfunction. Therefore, quantitation of altered perfusion can aid research into the mechanisms of retinal pathologies. Intravital video microscopy of fluorescent tracers can be used to measure vascular diameters and bloodstream velocities of the retinal vasculature, specifically the arterioles branching from the central retinal artery and of the venules leading into the central retinal vein....

  3. Variação do fluxo sanguíneo da artéria central da retina durante as diferentes fases do ciclo menstrual ovulatório / Central retinal artery blood flow variation during menstrual cycle

    Scientific Electronic Library Online (English)

    Luiz Carlos, Viana; Michelle Amorim Costa, Burmann; Marcos, Sampaio; Selmo, Geber.

    2007-03-01

    Full Text Available OBJETIVO: avaliar a resistência vascular da artéria central da retina, por meio do fluxo Doppler, nas diferentes fases do ciclo menstrual ovulatório. MÉTODOS: estudo observacional, longitudinal e prospectivo com avaliação de 34 mulheres saudáveis, submetidas a estudo dopplerfluxométrico do fundo do [...] olho para avaliação da resistência vascular da artéria central da retina nas posições sentada e deitada, durante quatro fases do ciclo menstrual: fase folicular inicial, fase folicular média, fase periovulatória e fase lútea média. A confirmação da ovulação no ciclo de estudo foi feita pela dosagem de progesterona sérica na fase lútea média. Foram avaliados os índices de pulsatilidade (IP) e de resistência, e as velocidades máxima, mínima e média. RESULTADOS: a idade média foi de 29,7 anos. Não foram observadas diferenças entre os índices obtidos para ambos os olhos; assim, utilizamos as médias dos índices para realizar o cálculo estatístico. Quando comparadas às posições de realização do exame, detectou-se um IP maior na posição sentada; assim, as análises foram avaliadas em separado, respeitando-se a posição da paciente. O IP da artéria central da retina, avaliado com a paciente deitada, variou durante o ciclo menstrual, apresentando-se significativamente mais baixo nas fases folicular média (1,5±0,3) e periovulatória (1,5±0,3) quando comparadas às fases folicular precoce (1,7±0,4) e lútea média (1,7±0,4). Quando a avaliação foi feita com a paciente sentada não foram observadas diferenças para as diferentes fases do ciclo. CONCLUSÕES: num ciclo menstrual ovulatório ocorre diminuição da resistência vascular na artéria central da retina e posterior reversão do efeito, como demonstrado pelas variações do IP. Abstract in english PURPOSE: to evaluate the vascular blood flow of the central retinal arteries using dopplervelocimetry in the different phases of the ovulatory menstrual cycle. METHODS: we performed an observational, longitudinal and prospective study evaluating 34 healthy and ovulatory women. All women were submitt [...] ed to Doppler scan of the eye to evaluate the vascular resistance of the central retinal arteries, either lying down or on a seated position, during four phases of the menstrual cycle. Confirmation of ovulation was performed by measuring serum progesterone during the luteal phase. We analyzed the pulsatility and resistance index and the maximum, minimum and mean velocity. RESULTS: mean age was 29.7 years. No differences were observed between the indexes obtained in both eyes, therefore a mean index was used for comparisons. As the comparison between the positions used for the exams showed a higher PI for the seated position, the analyses were performed separately. The pulsatility index in the lying position was different among the different phases of the menstrual cycle. The arterial resistance was significantly lower during the intermediate follicular and the periovulatory phases, as compared to the early follicular and luteal phases. When the comparison was performed with the patient in the seated position, no differences were observed. CONCLUSIONS: Our results demonstrate a reduction in the vascular resistance of the cerebral microcirculation and a posterior reversal, as shown by changes in the PI.

  4. Variação do fluxo sanguíneo da artéria central da retina durante as diferentes fases do ciclo menstrual ovulatório Central retinal artery blood flow variation during menstrual cycle

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Viana

    2007-03-01

    Full Text Available OBJETIVO: avaliar a resistência vascular da artéria central da retina, por meio do fluxo Doppler, nas diferentes fases do ciclo menstrual ovulatório. MÉTODOS: estudo observacional, longitudinal e prospectivo com avaliação de 34 mulheres saudáveis, submetidas a estudo dopplerfluxométrico do fundo do olho para avaliação da resistência vascular da artéria central da retina nas posições sentada e deitada, durante quatro fases do ciclo menstrual: fase folicular inicial, fase folicular média, fase periovulatória e fase lútea média. A confirmação da ovulação no ciclo de estudo foi feita pela dosagem de progesterona sérica na fase lútea média. Foram avaliados os índices de pulsatilidade (IP e de resistência, e as velocidades máxima, mínima e média. RESULTADOS: a idade média foi de 29,7 anos. Não foram observadas diferenças entre os índices obtidos para ambos os olhos; assim, utilizamos as médias dos índices para realizar o cálculo estatístico. Quando comparadas às posições de realização do exame, detectou-se um IP maior na posição sentada; assim, as análises foram avaliadas em separado, respeitando-se a posição da paciente. O IP da artéria central da retina, avaliado com a paciente deitada, variou durante o ciclo menstrual, apresentando-se significativamente mais baixo nas fases folicular média (1,5±0,3 e periovulatória (1,5±0,3 quando comparadas às fases folicular precoce (1,7±0,4 e lútea média (1,7±0,4. Quando a avaliação foi feita com a paciente sentada não foram observadas diferenças para as diferentes fases do ciclo. CONCLUSÕES: num ciclo menstrual ovulatório ocorre diminuição da resistência vascular na artéria central da retina e posterior reversão do efeito, como demonstrado pelas variações do IP.PURPOSE: to evaluate the vascular blood flow of the central retinal arteries using dopplervelocimetry in the different phases of the ovulatory menstrual cycle. METHODS: we performed an observational, longitudinal and prospective study evaluating 34 healthy and ovulatory women. All women were submitted to Doppler scan of the eye to evaluate the vascular resistance of the central retinal arteries, either lying down or on a seated position, during four phases of the menstrual cycle. Confirmation of ovulation was performed by measuring serum progesterone during the luteal phase. We analyzed the pulsatility and resistance index and the maximum, minimum and mean velocity. RESULTS: mean age was 29.7 years. No differences were observed between the indexes obtained in both eyes, therefore a mean index was used for comparisons. As the comparison between the positions used for the exams showed a higher PI for the seated position, the analyses were performed separately. The pulsatility index in the lying position was different among the different phases of the menstrual cycle. The arterial resistance was significantly lower during the intermediate follicular and the periovulatory phases, as compared to the early follicular and luteal phases. When the comparison was performed with the patient in the seated position, no differences were observed. CONCLUSIONS: Our results demonstrate a reduction in the vascular resistance of the cerebral microcirculation and a posterior reversal, as shown by changes in the PI.

  5. Retinitis Pigmentosa.

    Science.gov (United States)

    Carr, Ronald E.

    1979-01-01

    The author describes the etiology of retinitis pigmentosa, a visual dysfunction which results from progressive loss of the retinal photoreceptors. Sections address signs and symptoms, ancillary findings, heredity, clinical diagnosis, therapy, and research. (SBH)

  6. Spectrophotometric retinal oximetry in pigs

    DEFF Research Database (Denmark)

    Traustason, Sindri; Kiilgaard, Jens Folke; Karlsson, Robert; Hardarson, Sveinn H; Stefansson, Einar; la Cour, Morten

    2013-01-01

    PURPOSE: To assess the validity of spectrophotometric retinal oximetry, by comparison to blood gas analysis and intra-vitreal measurements of partial pressure of oxygen (pO2). METHODS: Female domestic pigs were used for all experiments (n=8). Oxygen fraction in inspired air was changed using a mixture of room air, pure oxygen and pure nitrogen, ranging from 5% to 100% oxygen. Femoral arterial blood gas analysis and retinal oximetry was performed at each level of inspiratory oxygen fraction. Reti...

  7. Spectrophotometric retinal oximetry in pigs

    DEFF Research Database (Denmark)

    Traustason, Sindri; Kiilgaard, Jens Folke; Karlsson, Robert; Hardarson, Sveinn H; Stefansson, Einar; la Cour, Morten

    2013-01-01

    , Reykjavik, Iceland). The device simultaneously acquires images at two wavelengths (570 nm and 600 nm) and specialized software automatically detects retinal blood vessels. In three pigs, invasive pO2-measurements were performed after the initial non-invasive measurements. RESULTS: Comparison of femoral......PURPOSE: To assess the validity of spectrophotometric retinal oximetry, by comparison to blood gas analysis and intra-vitreal measurements of partial pressure of oxygen (pO2). METHODS: Female domestic pigs were used for all experiments (n=8). Oxygen fraction in inspired air was changed using a...... mixture of room air, pure oxygen and pure nitrogen, ranging from 5% to 100% oxygen. Femoral arterial blood gas analysis and retinal oximetry was performed at each level of inspiratory oxygen fraction. Retinal oximetry was performed using a commercial instrument, the Oxymap Retinal Oximeter T1 (Oxymap ehf...

  8. Glutamate escape from a tortuous synaptic cleft of the hippocampal mossy fibre synapse.

    Science.gov (United States)

    Savtchenko, Leonid P; Rusakov, Dmitri A

    2004-09-01

    The time course of neurotransmitter in the synaptic cleft contributes substantially to the fast kinetics of synaptic signalling. Hippocampal mossy fibres (MFs), a well-characterised excitatory pathway from dentate granule cells to the hippocampus proper, form large glutamatergic synapses at branched spiny structures in CA3 pyramidal cell dendrites. To what extent transmission at these synapses is affected by retarded glutamate clearance from the large tortuous synaptic cleft is not known. Here, we propose a simple geometrical approximation representing the 'typical' geometry of thorny excrescences that form the tortuous cleft interface at a MF synapse. We then employ Monte Carlo simulations to monitor movements of 3000 individual glutamate molecules released within the cleft. The results predict that, in the absence of neuronal glutamate transporters, it should take approximately 10 ms for 50% and 60-70 ms for 90% of glutamate molecules to escape the MF synapse. PMID:15186913

  9. Spectrophotometric retinal oximetry in pigs

    DEFF Research Database (Denmark)

    Traustason, Sindri; Kiilgaard, Jens Folke

    2013-01-01

    PURPOSE: To assess the validity of spectrophotometric retinal oximetry, by comparison to blood gas analysis and intra-vitreal measurements of partial pressure of oxygen (pO2). METHODS: Female domestic pigs were used for all experiments (n=8). Oxygen fraction in inspired air was changed using a mixture of room air, pure oxygen and pure nitrogen, ranging from 5% to 100% oxygen. Femoral arterial blood gas analysis and retinal oximetry was performed at each level of inspiratory oxygen fraction. Retinal oximetry was performed using a commercial instrument, the Oxymap Retinal Oximeter T1 (Oxymap ehf, Reykjavik, Iceland). The device simultaneously acquires images at two wavelengths (570 nm and 600 nm) and specialized software automatically detects retinal blood vessels. In three pigs, invasive pO2-measurements were performed after the initial non-invasive measurements. RESULTS: Comparison of femoral arterial oxygen saturation and the optical density ratio over retinal arteries revealed an approximately linear relationship (R(2) = 0.74, p = 3.4 x 10(-9)). In order to test the validity of applying the arterial calibration to veins, we compared non-invasive oximetry measurements to invasive pO2-measurements in three pigs. This relationship was approximately linear (R(2) = 0.45, p = 0.04). CONCLUSIONS: Non-invasive spectrophotometric oximetry is sensitive to changes in oxygen saturation in pigs and correlated with intravitreal pO2-measurements and with femoral artery pO2. Pigs present a higher intra-individual variability in retinal oxygen saturation and a lower overall saturation than humans. The difference between porcine and human eyes makes direct comparisons of measurements difficult.

  10. Platelet size and density affect shear-induced thrombus formation in tortuous arterioles

    International Nuclear Information System (INIS)

    Thrombosis accounts for 80% of deaths in patients with diabetes mellitus. Diabetic patients demonstrate tortuous microvessels and larger than normal platelets. Large platelets are associated with increased platelet activation and thrombosis, but the physical effects of large platelets in the microscale processes of thrombus formation are not clear. Therefore, the objective of this study was to determine the physical effects of mean platelet volume (MPV), mean platelet density (MPD) and vessel tortuosity on platelet activation and thrombus formation in tortuous arterioles. A computational model of the transport, shear-induced activation, collision, adhesion and aggregation of individual platelets was used to simulate platelet interactions and thrombus formation in tortuous arterioles. Our results showed that an increase in MPV resulted in a larger number of activated platelets, though MPD and level of tortuosity made little difference on platelet activation. Platelets with normal MPD yielded the lowest amount of mural thrombus. With platelets of normal MPD, the amount of mural thrombus decreased with increasing level of tortuosity but did not have a simple monotonic relationship with MPV. The physical mechanisms associated with MPV, MPD and arteriole tortuosity play important roles in platelet activation and thrombus formation. (paper)

  11. Learning about Retinitis Pigmentosa

    Science.gov (United States)

    ... genetic terms used on this page Learning About Retinitis Pigmentosa What is retinitis pigmentosa? What are the symptoms ... Pigmentosa Additional Resources for Retinitis Pigmentosa What is retinitis pigmentosa? Retinitis pigmentosa (RP) is the name given to ...

  12. Retinitis pigmentosa

    OpenAIRE

    Hamel Christian

    2006-01-01

    Abstract Retinitis pigmentosa (RP) is an inherited retinal dystrophy caused by the loss of photoreceptors and characterized by retinal pigment deposits visible on fundus examination. Prevalence of non syndromic RP is approximately 1/4,000. The most common form of RP is a rod-cone dystrophy, in which the first symptom is night blindness, followed by the progressive loss in the peripheral visual field in daylight, and eventually leading to blindness after several decades. Some extreme cases may...

  13. Retinitis pigmentosa

    OpenAIRE

    Hamel, Christian,

    2006-01-01

    Retinitis pigmentosa (RP) is an inherited retinal dystrophy caused by the loss of photoreceptors and characterized by retinal pigment deposits visible on fundus examination. Prevalence of non syndromic RP is approximately 1/4,000. The most common form of RP is a rod-cone dystrophy, in which the first symptom is night blindness, followed by the progressive loss in the peripheral visual field in daylight, and eventually leading to blindness after several decades. Some extreme cases may have a r...

  14. Retinitis pigmentosa.

    OpenAIRE

    Hamel, Christian,

    2006-01-01

    Retinitis pigmentosa (RP) is an inherited retinal dystrophy caused by the loss of photoreceptors and characterized by retinal pigment deposits visible on fundus examination. Prevalence of non syndromic RP is approximately 1/4,000. The most common form of RP is a rod-cone dystrophy, in which the first symptom is night blindness, followed by the progressive loss in the peripheral visual field in daylight, and eventually leading to blindness after several decades. Some extreme cases may have a r...

  15. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit; Kyvik, Kirsten O; Kessel, Line; Hougaard, Jesper L; Sørensen, Thorkild I A

    2006-01-01

    PURPOSE: To assess the relative influence of genetic and environmental effects on retinal vessel diameters and blood pressure in healthy adults, as well as the possible genetic connection between these two characteristics. METHODS: In 55 monozygotic and 50 dizygotic same-sex healthy twin pairs, aged 20 to 46 years, interpolated diameter estimates for the central retinal artery (CRAE), the central retinal vein (CRVE), and the artery-to-vein diameter ratio (AVR) were assessed by analysis of digita...

  16. Smooth Muscle Cell Contraction Increases the Critical Buckling Pressure of Arteries

    OpenAIRE

    Hayman, Danika M.; Zhang, Jinzhou; Liu, Qin; Xiao, Yangming; Han, Hai-Chao

    2012-01-01

    Recent in vitro experiments demonstrated that arteries under increased internal pressure or decreased axial stretch may buckle into the tortuous pattern that is commonly observed in aging or diseased arteries in vivo. It suggests that buckling is a possible mechanism for the development of artery tortuosity. Vascular tone has significant effects on arterial mechanical properties but its effect on artery buckling is unknown. The objective of this study was to determine the effects of smooth mu...

  17. AUTOMATIC RETINAL VESSEL TORTUOSITY MEASUREMENT

    Directory of Open Access Journals (Sweden)

    Nidhal Khdhair El Abbadi

    2013-01-01

    Full Text Available Retinal vascular vessels have the role to indicate the retinal diseases and for systematic diseases when there are any abnormalities in retinal vascular pattern. A characteristic of the vascular pattern that is appreciated by clinicians is vascular tortuosity, i.e., how curved or kinked a blood vessel, either vein or artery, appears along its course. In this study we suggest a novel mask filter to track the blood vessel along its course and measuring the blood vessels tortuosity over the entire human retinal vessel network in fundus eye image, by using the arc to chord ratio. The suggested algorithm tested with straight and curve hand drawing lines and gives high accurate results.

  18. Retinitis Pigmentosa

    Science.gov (United States)

    ... inherited diseases causing retinal degeneration. The cell-rich retina lines the back inside wall of the eye. It is responsible for capturing images from the visual field. People with RP experience ...

  19. Anatomic and functional outcome of eyes with massive submacular hemorrhage secondary to retinal macroaneurysm submitted to vitrectomy / Resultados anatômicos e funcionais em pacientes com hemorragia submacular maciça secundária à macroaneurisma arterial de retina submetidos à vitrectomia posterior

    Scientific Electronic Library Online (English)

    Leonardo Provetti, Cunha; Luciana Virgínia Ferreira Costa, Cunha; Carolina Ferreira, Costa; Hugo Henrique, Moreira; Mário Luiz Ribeiro, Monteiro.

    2015-02-01

    Full Text Available Objetivo: Relatar os resultados anatômicos e funcionais em uma série de pacientes com perda visual grave por hemorragia submacular maciça aguda secundária a macroaneurisma arterial de retina (MAR) e descrever a técnica cirúrgica utilizada. Métodos: Este é um estudo retrospectivo, observacional, sér [...] ie de casos, incluindo 4 olhos de 4 pacientes que foram submetidos à cirurgia de vitrectomia posterior (VP), associada a peeling da membrane limitante interna (MLI) e injeção sub-retiniana de ativador do plasminogênio tecidual recombinante (rtPA-12,5 mg/0.1 ml) por hemorragia submacular maciça recente (?7 dias) secundária MAR. Em todos os casos, o exame de tomografia de coerência óptica (OCT) foi obtido na consulta inicial e nas subsequentes para avaliação das alterações estruturais da retina. Resultados: A idade dos pacientes variou entre 63 a 78 anos e todos apresentavam hipertensão arterial sistêmica. A acuidade visual inicial nos olhos afetados variou de movimento de mãos a conta dedos a 50 cm. Todos os olhos apresentaram hemorragia retiniana extensa ocupando mais do que dois terços da região macular. O tempo decorrido entre a perda visual e a cirurgia variou entre 3 a 7 dias. Após um seguimento médio de 15.5 ± 5.19 meses (variando entre 10 a 22 meses), a acuidade visual pós-operatória variou entre 20/30 e 20/80. Todos os olhos apresentaram um deslocamento completo da hemorragia subretiniana da região macular central no pós operatório. As imagens seccionais da retina obtidas pela OCT revelaram um afilamento da retina neurossensorial e interrupções na linha refletiva que representa a junção entre os segmentos internos e externos dos fotorreceptores na região macular, além de falhas na membrane limitante externa em todos os casos. Conclusão: De acordo com os resultados do presente estudo, a VP associada à injeção sub-retiniana de rtPA parece ser uma técnica segura e eficaz em promover melhora visual em pacientes com hemorragia submacular maciça secundária a MAR. Os achados do OCT revelaram que, apesar da grande melhora visual apresentada, a presença de hemorragia submacular pode promover danos estruturais permanentes da retina neurossensorial, em especial ao segmento externo dos fotorreceptores. Abstract in english Purpose: To report the anatomic and functional outcome in patients with severe visual loss after acute massive submacular hemorrhage secondary to retinal arterial macroaneurysm submitted to vitrectomy and subretinal recombinant tissue plasminogen activator injection. Methods: Retrospective, observa [...] tional, case-series of 4 eyes of 4 patients submitted to pars plana posterior vitrectomy (ppV) combined with internal limiting membrane (ILM) removal and subretinal recombinant tissue plasminogen activator (rtPA-12.5 mg/0.1 ml) injection with dilute (20%) sulfur hexafluoride (SF6) gas in the vitreous cavity of eyes with recent onset (?7 days) massive macular hemorrhage due to retinal arterial macroaneurysm (RAMA). Optical coherence tomography (OCT) was obtained both at presentation and during follow up. Results: Patients ranged in age from 63 to 78 years and all had systemic arterial hypertension. Visual acuity at presentation ranged from hand motions to count fingers at 50 cm. All eyes showed extensive retinal hemorrhage involving more than two-thirds of macular area. The time between the onset of symptoms and the surgery ranged from 3 to 7 days. After a mean postoperative follow-up of 15.5 ± 5.19 months (range, 10-22 months), all eyes showed visual acuity improvement and final visual acuity ranged from 20/30 to 20/80. All had complete displacement of the subretinal hemorrhage from the fovea after the surgery. OCT images showed neurosensory retina thinning and disruption of the reflective line that represents the junction between inner and outer photoreceptors segments (IS/OS line) beneath the macular area and absence of the external limiting membrane (ELM). Conclusions: ppV associated with subretinal rtPA injection with intravitreal g

  20. Intravitreal bevacizumab in congenital retinal macrovessel with retinal arteriolar macroaneurysm.

    Science.gov (United States)

    Goel, Neha; Kumar, Vinod; Seth, Anisha; Ghosh, Basudeb

    2015-01-01

    Congenital retinal macrovessel (CRM) refers to an aberrant vessel, usually a vein, which traverses the macula and supplies both sides of the horizontal raphe. It is a rare condition, mostly asymptomatic and discovered on routine examination. We describe a case of both arterial and venous CRM with a macroaneurysm along the arterial CRM that presented with decreased vision due to prominent lipid exudation at the macula. Treatment with intravitreal bevacizumab resulted in a favourable anatomical as well as functional outcome. To the best of our knowledge, this is the first report of this unusual presentation of CRM, and its successful management with intravitreal bevacizumab. PMID:26586981

  1. Unilateral central retinal artery occlusion as the sole presenting sign of Susac syndrome in a young man: case report / Oclusão unilateral da artéria central da retina como único sinal de apresentação da síndrome de Susac em jovem do sexo masculino: relato de caso

    Scientific Electronic Library Online (English)

    Samira Luiza dos, Apóstolos-Pereira; Lúcia B. Passos, Kara-José; Paulo Euripedes, Marchiori; Mário Luiz Ribeiro, Monteiro.

    2013-06-01

    Full Text Available Descrevemos um paciente de 24 anos, sexo masculino, que se apresentou com perda súbita da visão do olho esquerdo causado por oclusão da artéria central da retina. Ele foi submetido à investigação clínica detalhada sem encontrar uma causa. Três semanas depois, no entanto, desenvolveu surdez, encefalo [...] patia e múltiplas oclusões de ramo arterial da retina no olho direito. Angiofluoresceinografia confirmou as oclusões de ramo arterial no OD e oclusão da artéria central da retina no OE, sem qualquer sinal de vascutile. O exame neurológico revelou encefalopatia difusa, enquanto que o estudo efetuado por ressonância nuclear magnética mostrou várias áreas de enfarte do cérebro e a audiometria demonstrou perda auditiva neurosensorial bilateral. A síndrome de Susac foi diagnosticada e tratamento com metilprednisolona e ciclofosfamida instituido com melhora discreta, seguida de estabilização clínica. Este caso é importante para chamar a atenção de que nem todos os três critérios diagnósticos (encefalopatia, oclusão de ramo arterial retiniano e surdez) para a síndrome de Susac precisam estar presentes de início, o que pode causar confusão diagnóstica. O diagnóstico deve portanto ser incluído no diferencial de oclusão da artéria central da retina mesmo quando ocorre em homem sem outros sintomas associados. Abstract in english We report the case of a 24-year-old man presenting with sudden visual loss in the left eye from a central retinal artery occlusion. An extensive clinical investigation revealed no etiology. Three weeks later, however, the patient developed hearing loss followed by encephalopathy and multiple branch [...] retinal artery occlusions in the right eye. Fluorescein angiography confirmed retinal vascular occlusions with no sign of vasculitis. The neurological examination revealed a diffuse encephalopathy while the MRI scan disclosed several small areas of infarcts in the brain. Bilateral sensorineural hearing loss was confirmed on audiometry. The patient was diagnosed with Susac syndrome and treated with methylprednisolone and cyclophosphamide, resulting in slight improvement and stabilization. This case shows that Susac syndrome may be diagnosed late due to the absence at onset of one or more of the symptoms of the classic triad (encephalopathy, multiple branch retinal artery occlusions and hearing loss). This case also serves to emphasize that Susac syndrome should be considered in the differential diagnosis of central retinal artery occlusion, even in apparently healthy young men.

  2. Coronary artery anatomy and variants

    Energy Technology Data Exchange (ETDEWEB)

    Malago, Roberto; Pezzato, Andrea; Barbiani, Camilla; Alfonsi, Ugolino; Nicoli, Lisa; Caliari, Giuliana; Pozzi Mucelli, Roberto [Policlinico G.B. Rossi, University of Verona, Department of Radiology, Verona (Italy)

    2011-12-15

    Variants and congenital anomalies of the coronary arteries are usually asymptomatic, but may present with severe chest pain or cardiac arrest. The introduction of multidetector CT coronary angiography (MDCT-CA) allows the detection of significant coronary artery stenosis. Improved performance with isotropic spatial resolution and higher temporal resolution provides a valid alternative to conventional coronary angiography (CCA) in many patients. MDCT-CA is now considered the ideal tool for three-dimensional visualization of the complex and tortuous anatomy of the coronary arteries. With multiplanar and volume-rendered reconstructions, MDCT-CA may even outperform CCA in determining the relative position of vessels, thus providing a better view of the coronary vascular anatomy. The purpose of this review is to describe the normal anatomy of the coronary arteries and their main variants based on MDCT-CA with appropriate reconstructions. (orig.)

  3. Coronary artery anatomy and variants

    International Nuclear Information System (INIS)

    Variants and congenital anomalies of the coronary arteries are usually asymptomatic, but may present with severe chest pain or cardiac arrest. The introduction of multidetector CT coronary angiography (MDCT-CA) allows the detection of significant coronary artery stenosis. Improved performance with isotropic spatial resolution and higher temporal resolution provides a valid alternative to conventional coronary angiography (CCA) in many patients. MDCT-CA is now considered the ideal tool for three-dimensional visualization of the complex and tortuous anatomy of the coronary arteries. With multiplanar and volume-rendered reconstructions, MDCT-CA may even outperform CCA in determining the relative position of vessels, thus providing a better view of the coronary vascular anatomy. The purpose of this review is to describe the normal anatomy of the coronary arteries and their main variants based on MDCT-CA with appropriate reconstructions. (orig.)

  4. Retinal detachment and retinal holes in retinitis pigmentosa sine pigmento.

    Science.gov (United States)

    Csaky, K; Olk, R J; Mahl, C F; Bloom, S M

    1991-01-01

    Retinal detachment and retinal holes in two family members with retinitis pigmentosa sine pigmento are reported. We believe these are the first such cases reported in the literature. We describe the presenting symptoms and management, including cryotherapy, scleral buckling procedure, and sulfur hexafluoride injection (SF6), resulting in stable visual acuity in one case and retinal reattachment and improved visual acuity in the other case. PMID:1841673

  5. Retinitis pigmentosa

    Directory of Open Access Journals (Sweden)

    Hamel Christian

    2006-10-01

    Full Text Available Abstract Retinitis pigmentosa (RP is an inherited retinal dystrophy caused by the loss of photoreceptors and characterized by retinal pigment deposits visible on fundus examination. Prevalence of non syndromic RP is approximately 1/4,000. The most common form of RP is a rod-cone dystrophy, in which the first symptom is night blindness, followed by the progressive loss in the peripheral visual field in daylight, and eventually leading to blindness after several decades. Some extreme cases may have a rapid evolution over two decades or a slow progression that never leads to blindness. In some cases, the clinical presentation is a cone-rod dystrophy, in which the decrease in visual acuity predominates over the visual field loss. RP is usually non syndromic but there are also many syndromic forms, the most frequent being Usher syndrome. To date, 45 causative genes/loci have been identified in non syndromic RP (for the autosomal dominant, autosomal recessive, X-linked, and digenic forms. Clinical diagnosis is based on the presence of night blindness and peripheral visual field defects, lesions in the fundus, hypovolted electroretinogram traces, and progressive worsening of these signs. Molecular diagnosis can be made for some genes, but is not usually performed due to the tremendous genetic heterogeneity of the disease. Genetic counseling is always advised. Currently, there is no therapy that stops the evolution of the disease or restores the vision, so the visual prognosis is poor. The therapeutic approach is restricted to slowing down the degenerative process by sunlight protection and vitaminotherapy, treating the complications (cataract and macular edema, and helping patients to cope with the social and psychological impact of blindness. However, new therapeutic strategies are emerging from intensive research (gene therapy, neuroprotection, retinal prosthesis.

  6. Treatment of splenic artery aneurysm with double overlapping bare stents: case report

    International Nuclear Information System (INIS)

    The traditional treatment of splenic artery aneurysm (SAA) is generally surgery and/or transcatheter arterial embolization, but recently, the treatment of SAA using a stent graft has been reported. However, the acute angle of the celiac axis, as well as the tortuous path of the splenic artery makes the use of stent graft difficult for treatment of aneurysma. We report here a case of SAA treated with the technique of double overlapping metallic stents

  7. Treatment of splenic artery aneurysm with double overlapping bare stents: case report

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Hyo Sung; Han, Young Min; Jin, Gong Yong [School of Medicine, Chonbuk National Univ., Chonju (Korea, Republic of)

    2004-09-01

    The traditional treatment of splenic artery aneurysm (SAA) is generally surgery and/or transcatheter arterial embolization, but recently, the treatment of SAA using a stent graft has been reported. However, the acute angle of the celiac axis, as well as the tortuous path of the splenic artery makes the use of stent graft difficult for treatment of aneurysma. We report here a case of SAA treated with the technique of double overlapping metallic stents.

  8. Retinal vascular calibre and response to light exposure and serial imaging

    OpenAIRE

    von Hanno, Therese; Sjølie, Anne Katrin; Mathiesen, Ellisiv B.

    2014-01-01

    Purpose To investigate whether retinal vessel calibre measurements on optical retinal photography are affected by light and dark exposure prior to photography and whether the vessel calibre changes during an imaging sequence of several images. Methods Digital optical retinal photographs were obtained from 32 healthy adults in two separate image sequences of six images during 1 min; one sequence with 10 min of dark exposure and one with 10 min of light exposure prior to imaging. Retinal arteri...

  9. : Peropsin in retinitis pigmentosa

    OpenAIRE

    Ksantini, Mohamed; Sénéchal, Audrey; Humbert, Ghyslaine; Arnaud, Bernard; Hamel, Christian

    2007-01-01

    Many genes from retinoid metabolism cause retinitis pigmentosa. Peropsin, an opsin-like protein with unknown function, is specifically expressed in apical retinal pigment epithelium microvilli. Since rhodopsin and RGR, another opsin-like protein, cause retinitis pigmentosa, we used D-HPLC to screen for the peropsin gene RRH in 331 patients (288 with retinitis pigmentosa and 82 with other retinal dystrophies). We found 13 nonpathogenic variants only, among which a c.730_731delATinsG that trunc...

  10. Blood pressure and retinal arteriolar narrowing in children.

    Science.gov (United States)

    Mitchell, Paul; Cheung, Ning; de Haseth, Kristin; Taylor, Bronwen; Rochtchina, Elena; Islam, F M Amirul; Wang, Jie Jin; Saw, Seang Mei; Wong, Tien Y

    2007-05-01

    Retinal arteriolar narrowing is a known response of hypertension and independently predicts cardiovascular mortality in adults. Whether elevated blood pressure leads to retinal arteriolar narrowing in young children is unknown. We examined the relationship of retinal vascular caliber and blood pressure levels in 2 population-based cohorts among children aged 6 to 8 years in Sydney, Australia (1572 children) and Singapore (380 children). Participants had digital retinal photographs and measurement of retinal arteriolar (or small artery) and venular (or small vein) caliber. Children with higher quartiles of blood pressure had significantly narrower retinal arterioles than those with lower blood pressure (retinal arteriolar caliber 162.8, 161.0, 157.8, and 157.1 microm (P for trendrefraction, and birth parameters, each 10-mm Hg increase in systolic blood pressure was associated with narrowing of the retinal arterioles by 2.08 microm (95% confidence interval: 1.38 to 2.79; P<0.0001) in Sydney children and 1.43 microm (95% confidence interval: 0.27 to 2.59; P=0.016) in Singapore children. These associations were consistent across age, sex, body mass index, and birth parameters. Retinal venules were not affected by blood pressure. We conclude that higher childhood blood pressure is associated with retinal arteriolar narrowing. Our data provide evidence that the effects of elevated blood pressure may manifest early in life. PMID:17372033

  11. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit; Kyvik, Kirsten O; Kessel, Line; Hougaard, Jesper L; Sørensen, Thorkild I A

    2006-01-01

    , aged 20 to 46 years, interpolated diameter estimates for the central retinal artery (CRAE), the central retinal vein (CRVE), and the artery-to-vein diameter ratio (AVR) were assessed by analysis of digital gray-scale fundus photographs of right eyes. RESULTS: The heritability was 70% (95% CI: 54...... for CRVE, and 0.67 +/- 0.05 microm for AVR. No significant influence on artery or vein diameters was found for gender, smoking, body mass index (BMI), total cholesterol, fasting blood glucose, or 2-hour oral glucose tolerance test values. CONCLUSIONS: In healthy young adults with normal blood pressure...

  12. Relationship between carotid artery stenosis and ischemic ocular diseases

    Directory of Open Access Journals (Sweden)

    Qian Chen

    2015-01-01

    Full Text Available AIM: To investigate the relationship between carotid artery stenosis and ischemic ocular diseases.METHODS: The clinical data of 30 cases(37 eyesof patients with ischemic eye diseases were collected from November 2010 to May 2014, and they were accepted the fundus fluorescein angiography(FFA, transcranial Doppler(TCDultrasonic blood vessels of the eye, neck vascular color Doppler flow imaging(CDFI, the neck CT angiography(CTAand carotid artery digital subtraction angiography(DSAexamination, and then the ischemic eye disease patients with ocular symptoms were analyzed. The peak systolic velocity(PSVand resistance index(RIof ophthalmic artery and central retinal artery were compared. Correlation between the internal carotid artery intima-media thickness(IMTand ophthalmic artery, central retinal artery PSV and RI correlation risk; ipsilateral internal carotid artery plaque and ophthalmic artery PSV and RI; PSV and RI associated ipsilateral internal carotid artery plaque and central retinal artery were analyzed. RESULTS: Eye symptoms: a black dim, reduced vision, the eyes flash, and around the eye pain were 75.7%, 83.8%, 51.4% and 32.4%; The eye signs: the dilatation of retinal vein, retinal hemorrhage, arterial stenosis and cotton spot and the contralateral side were regarded as main signs. Ophthalmic artery PSV and RI value of the differences were statistically significant(PPP>0.05; The ipsilateral internal carotid artery plaque and ophthalmic artery PSV had no correlation with RI values(P>0.05; PSV and RI and the ipsilateral internal carotid artery plaque and central retinal artery had no correlation(P>0.05.CONCLUSION: The incidence of ischemic eye diseases and internal carotid artery stenosis is associated with very close, the clinical can regard the degree of internal carotid artery stenosis as an important basis for diagnosis and treatment of eye diseases.

  13. Retinal Anatomy and Pathology.

    Science.gov (United States)

    Gupta, Mrinali Patel; Herzlich, Alexandra A; Sauer, Theodor; Chan, Chi-Chao

    2016-01-01

    Normal retina contains neuroretina and retinal pigment epithelium. The neuroretina consists of outer and inner segments of photoreceptors (rods and cones), external limiting membrane, outer nuclear layer, outer plexiform layer, inner nuclear layer, inner plexiform layer, ganglion cell layer, nerve fiber layer and internal limiting membrane. There is a broad spectrum of retinal pathology including congenital abnormalities, dystrophies, degenerations (notably age-related macular degeneration), retinal vascular diseases, toxicities, inflammatory diseases, neoplasms, retinal detachment, trauma and retinal involvement of systemic diseases. This chapter presents a few major pathological processes in retinal diseases, especially processes that are amenable to pharmacotherapeutics. PMID:26502225

  14. Retinal Tears and Detachments

    Science.gov (United States)

    ... have diabetes What are the symptoms of a retinal detachment? If part of the retina detaches, it will ... and prevent permanent vision loss. How is a retinal detachment diagnosed? A detached retina cannot be seen from ...

  15. Retinal Detachment Vision Simulator

    Science.gov (United States)

    ... Retinal Detachment Vision Simulator Retinal Detachment Vision Simulator Mar. 10, 2014 How does a detached or torn ... but not Right for Everyone Jun 30, 2015 Color Blindness May Soon Be Treatable With a Single ...

  16. Four-wavelength retinal vessel oximetry

    Science.gov (United States)

    Drewes, Jonathan Jensen

    1999-11-01

    This dissertation documents the design and construction of a four-wavelength retinal vessel oximeter, the Eye Oximeter (EOX). The EOX scans low-powered laser beams (at 629, 678, 821 and 899 nm) into the eye and across a targeted retinal vessel to measure the transmittance of the blood within the vessel. From the transmittance measurements, the oxygen saturation of the blood within the vessel is computed. Retinal vessel oxygen saturation has been suggested as a useful parameter for monitoring a wide range of conditions including occult blood loss and a variety of ophthalmic diseases. An artificial eye that simulates the geometry of a human retinal vessel was constructed and used to calibrate the EOX saturation measurement. A number of different oximetry equations were developed and tested. From measurements made on whole human blood in the artificial eye, an oximetry equation that places a linear wavelength dependance on the scattering losses (3% decrease from 629 to 899 nm) is found to best calibrate the EOX oxygen saturation measurement. This calibration also requires that an adjustment be made to the absorption coefficient of hemoglobin at 629 nm that has been reported in the literature. More than 4,000 measurements were made in the eyes of three human subjects during the development of the EOX. Applying the oximetry equation developed through the in vitro experiments to human data, the average human retinal venous oxygen saturation is estimated to be 0.63 +/- 0.07 and the average human retinal arterial oxygen saturation is 0.99 +/- 0.03. Furthermore, measurements made away from the optic disk resulted in a larger variance in the calculated saturation when compared to measurements made on the optic disk. A series of EOX experiments using anesthetized swine helped to verify the sensitivity of the EOX measurement of oxygen saturation. It is found that the calibration in swine differed from the calibration in the artificial eye. An empirical calibration from the swine measurements was applied to the human measurements. With this correction, the average human retinal venous oxygen saturation was found to be 0.40 +/- 0.08 and the average human retinal arterial oxygen saturation was found to be 0.98 +/- 0.03. This suggests that the swine, human and model eye measurements may each require a different calibration because of differences between the spectral characteristics of their ocular fundi. Finally, further in vitro and in vivo experimentation is proposed so that the goal of having an accurate, absolute measurement of the human retinal vessel oxygen saturation will be realized.

  17. Ophthalmodynamometric determination of the central retinal vessel collapse pressure correlated with systemic blood pressure

    OpenAIRE

    Jonas, J.B.

    2004-01-01

    Aims: To evaluate whether determination of the central retinal artery and vein collapse pressure correlate with systemic blood pressure measurements, using a new Goldmann contact lens associated ophthalmodynamometric device

  18. Cone pathway function in relation to asymmetric carotid artery stenosis

    DEFF Research Database (Denmark)

    Kofoed, Peter Kristian; Munch, Inger Christine; Holfort, Stig K; Sillesen, Henrik; Jensen, Leif Panduro; Iversen, Helle K; Larsen, Michael

    2013-01-01

    Purpose:  To examine retinal function in relation to retinal perfusion pressure in patients with carotid artery stenosis. Methods:  Thirteen patients with carotid artery stenosis without clinical eye disease underwent assessment of ophthalmic artery systolic blood pressure (OSP) by ocular...... pneumoplethysmography, carotid artery obstructive disease by ultrasonography, intraocular pressure by applanation tonometry, retinal perfusion by fluorescein angiography and retinal function by multifocal electroretinography (mfERG). Data analysis compared the eye on the most stenotic side with the fellow eye in the...... same patient. Results:  Ophthalmic systolic pressure was 95.8?±?13.1?mmHg on the side with the highest degree of carotid artery stenosis (mean 94.0%) and 111.7?±?10.3?mmHg in the fellow eyes on the side with the lesser degree of stenosis (mean 33.9%). Summed mfERG implicit times (N1 and P1) were 3...

  19. Modern retinal laser therapy

    OpenAIRE

    KOZAK, IGOR; Luttrull, Jeffrey K

    2014-01-01

    Medicinal lasers are a standard source of light to produce retinal tissue photocoagulation to treat retinovascular disease. The Diabetic Retinopathy Study and the Early Treatment Diabetic Retinopathy Study were large randomized clinical trials that have shown beneficial effect of retinal laser photocoagulation in diabetic retinopathy and have dictated the standard of care for decades. However, current treatment protocols undergo modifications. Types of lasers used in treatment of retinal dise...

  20. Retinal oximetry using ultrahigh-resolution optical coherence tomography

    Directory of Open Access Journals (Sweden)

    Ye Y

    2012-12-01

    Full Text Available Yufeng Ye,1,2 Hong Jiang,2,3 Meixiao Shen,4 Byron L Lam,2 Delia Cabrera DeBuc,2 Lili Ge,2,4 Mitra Sehi,2 Jianhua Wang21Hangzhou First People’s Hospital, Hangzhou, China; 2Bascom Palmer Eye Institute, 3Neurology, University of Miami, Miami, FL, USA; 4School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, ChinaBackground: The purpose of this study was to investigate the repeatability of retinal oximetry using slit-lamp adapted ultrahigh-resolution optical coherence tomography (SL-UHR-OCT.Methods: SL-UHR-OCT was developed and fringe patterns were obtained for a major retinal artery and a major retinal vein. A-scans at the central wavelengths of 805 nm and 855 nm were analyzed for calculating optical density ratios (ODRs, from which the percentage oxygen saturation was calculated. Measurements were made on two occasions for each person. Repeatability and coefficients of repeatability were calculated.Results: The mean ODRs of the artery were 0.79 ± 0.86 and 0.88 ± 0.97 in sessions 1 and 2, respectively. The mean ODRs of the vein were ?0.08 ± 0.69 and 0.14 ± 0.77 between the two sessions, and were significantly lower than that of the artery (P < 0.05. The coefficients of repeatability were 1.44 and 1.81 for the artery and vein, respectively. The mean oxygen saturation of the major retinal artery was 94% ± 45% and 98% ± 51% in sessions 1 and 2, respectively, and the mean oxygen saturation of the major retinal vein was 48% ± 36% and 60% ± 40% between sessions.Conclusion: Optical coherence tomographic oximetry for evaluating retinal oxygen saturation was subject to variation, although the averaged measurements in repeated sessions were matched. Further work on reducing variation will be needed.Keywords: ultrahigh-resolution optical coherence tomography, oximetry

  1. Measurement of retinal blood velocity

    Science.gov (United States)

    Winchester, Leonard W., Jr.; Chou, Nee-Yin

    2006-02-01

    A fundus camera was modified to illuminate the retina of a rabbit model with low power laser light in order to obtain laser speckle images. A fast-exposure charge-coupled device (CCD) camera was used to capture laser speckle images of the retina. Image acquisition was synchronized with the arterial pulses of the rabbit to ensure that all images are obtained at the same point in the cardiac cycle. The rabbits were sedated and a speculum was inserted to prevent the eyelid from closing. Both albino (New Zealand; pigmented (Dutch belted) rabbits were used in the study. The rabbit retina is almost avascular. The measurements are obtained for choroidal tissue as well as retinal tissue. Because the retina is in a region of high metabolism, blood velocity is strongly affected by blood oxygen saturation. Measurements of blood velocity obtained over a wide range of O II saturations (58%-100%) showed that blood velocity increases with decreasing O II saturation. For most experiments, the left eye of the rabbit was used for laser measurements whereas the right eye served as a control. No observable difference between pre- and post-experimented eye was noted. Histological examinations of retinal tissue subjected to repeated laser measurements showed no indication of tissue damage.

  2. VANISHING RETINAL DETACHMENT

    Science.gov (United States)

    2015-01-01

    Purpose: The purpose of this report is to describe a case of rhegmatogenous retinal detachment in the setting of chronic kidney disease that exhibited complete retinal reattachment after serial hemodialysis. Methods: Retrospective case report. Results: A 58-year-old woman with acute vision loss was found to have a macula-involving rhegmatogenous retinal detachment. Due to chronic kidney disease, she continued with routinely scheduled hemodialysis for 1 week until surgical clearance was obtained. Preoperative examination revealed complete reattachment of the retina with a persistent retinal tear. Barrier laser was applied to the tear and the retina remained attached until the most recent follow-up 8 months later. The workup of alternate etiologies was unrevealing. Conclusion: This case describes a temporal association between hemodialysis and resolution of subretinal fluid due to rhegmatogenous retinal detachment. A potential causal linkage is suggested based on shifting fluid dynamics associated with hemodialysis. A shift in treatment paradigm is not advised. PMID:26352323

  3. Modern retinal laser therapy.

    Science.gov (United States)

    Kozak, Igor; Luttrull, Jeffrey K

    2015-01-01

    Medicinal lasers are a standard source of light to produce retinal tissue photocoagulation to treat retinovascular disease. The Diabetic Retinopathy Study and the Early Treatment Diabetic Retinopathy Study were large randomized clinical trials that have shown beneficial effect of retinal laser photocoagulation in diabetic retinopathy and have dictated the standard of care for decades. However, current treatment protocols undergo modifications. Types of lasers used in treatment of retinal diseases include argon, diode, dye and multicolor lasers, micropulse lasers and lasers for photodynamic therapy. Delivery systems include contact lens slit-lamp laser delivery, indirect ophthalmocope based laser photocoagulation and camera based navigated retinal photocoagulation with retinal eye-tracking. Selective targeted photocoagulation could be a future alternative to panretinal photocoagulation. PMID:25892934

  4. Modern retinal laser therapy

    Science.gov (United States)

    Kozak, Igor; Luttrull, Jeffrey K.

    2014-01-01

    Medicinal lasers are a standard source of light to produce retinal tissue photocoagulation to treat retinovascular disease. The Diabetic Retinopathy Study and the Early Treatment Diabetic Retinopathy Study were large randomized clinical trials that have shown beneficial effect of retinal laser photocoagulation in diabetic retinopathy and have dictated the standard of care for decades. However, current treatment protocols undergo modifications. Types of lasers used in treatment of retinal diseases include argon, diode, dye and multicolor lasers, micropulse lasers and lasers for photodynamic therapy. Delivery systems include contact lens slit-lamp laser delivery, indirect ophthalmocope based laser photocoagulation and camera based navigated retinal photocoagulation with retinal eye-tracking. Selective targeted photocoagulation could be a future alternative to panretinal photocoagulation. PMID:25892934

  5. Transient tractional retinal detachment in an eye with retinitis pigmentosa

    Directory of Open Access Journals (Sweden)

    Shuichiro Hirahara

    2010-09-01

    Full Text Available Shuichiro Hirahara, Yoshio Hirano, Tsutomu Yasukawa, Yuichiro OguraDepartment of Ophthalmology and Visual Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, JapanAbstract: We present a case of retinitis pigmentosa with vitreoretinal traction-associated retinal detachment. The retinal detachment was detected in the nasal periphery. No retinal breaks and no active vascular leakage were observed by fundus scopy and fluorescein angiography, respectively. However, 8 months later, the tractional retinal detachment was spontaneously resolved with posterior vitreous detachment.Keywords: retinitis pigmentosa, vitreoretinal traction, retinal detachment

  6. [The function of the precortical arteries].

    Science.gov (United States)

    Gordeladze, Z T; Baramidze, D G; Levkovich, Iu I

    1991-06-01

    In anesthetized adult rabbits, the responses of pial and precortical arteries to retinal photostimulation and the application of 0.5% strychnine solution to the brain surface were studied, as well as the distribution of cholinergic and adrenergic nerve fibres in these microvessels. The precortical arteries showed the highest degree of dilatation and frequency of responses. Dense innervation was mostly in evidence in the precortical arteries. Upon atropin application, the response suppression was also more obvious in the precortical arteries. The data suggest that the precortical arteries play an important role in regulation of the adequate blood supply to the brain tissue. PMID:1665822

  7. Retinal vascular calibre and response to light exposure and serial imaging

    DEFF Research Database (Denmark)

    von Hanno, T.; Sjølie, Anne K.; Mathiesen, E. B.

    2014-01-01

    Purpose: To investigate whether retinal vessel calibre measurements on optical retinal photography are affected by light and dark exposure prior to photography and whether the vessel calibre changes during an imaging sequence of several images. Methods: Digital optical retinal photographs were...... obtained from 32 healthy adults in two separate image sequences of six images during 1 min; one sequence with 10 min of dark exposure and one with 10 min of light exposure prior to imaging. Retinal arteriolar and venular calibres were measured computer-assisted and summarized as central retinal artery and....... Conclusions: Retinal venular calibre was wider with light exposure prior to imaging and increased slightly during the imaging sequences, less pronounced after prior light than dark exposure. Measurement error due to these effects will probably be reduced by avoiding dark prior to imaging, and a possible bias...

  8. Kyrieleis´ vasculitis in acute retinal necrosis

    Directory of Open Access Journals (Sweden)

    Ester Francés-Muñoz

    2010-07-01

    Full Text Available Ester Francés-Muñoz1, Roberto Gallego-Pinazo1, Ruth López-Lizcano1, Salvador García-Delpech1, J Luis Mullor3, Manuel Díaz-Llopis1,21Department of Ophthalmology, Hospital La Fe, Valencia, Spain; 2University of Valencia, Valencia, Spain; 3Unit of Experimental Ophthalmology. Fundación para la Investigación del Hospital Universitario La Fe. Valencia, Valencia, SpainAbstract: We report the first case in the literature of Kyrieleis´ vasculitis related to acute retinal necrosis by Varicella zoster virus in a 76-year-old woman with bilateral involvement. In our patient the arterial lesions appeared 15 days after the initial presentation.Keywords: Kyrieleis´ vasculitis, retinal necrosis, herpes virus

  9. Retinal detachment repair

    Science.gov (United States)

    ... rhegmatogenous retinal detachments. These occur due to a hole or tear in the retina. ... the eye inward so that it meets the hole in the retina. Scleral buckling can be done using numbing medicine while you ...

  10. Retinal and choroidal intravascular spectral-domain optical coherence tomography

    DEFF Research Database (Denmark)

    Willerslev, Anne; Li, Xiao

    2014-01-01

    Purpose:? To examine retinal and choroidal blood vessels using spectral-domain optical coherence tomography (SD-OCT). Methods:? Retrospective case series. Results:? Scans through retinal blood vessels in healthy subjects demonstrated vessel wall reflexes and a tri-layer profile of the blood column on longitudinal scans and a figure-of-eight configuration on cross-sectional scans. Intravascular reflectivity decreased with increasingly oblique angles of observation and was absent when blood flow was parallel to the line of sight. The high blood flow in the choroidal vessels in healthy subjects and the low flow in the retinal vessels in patients with ocular ischaemic syndrome and central retinal artery occlusion were both associated with lower reflectivity of the blood and an unstructured intravascular SD-OCT profile. Discussion:? This qualitative in vivo study found a characteristically structured SD-OCT profile of the blood column in retinal vessels with normal blood flow. Both structure and total reflectivityfaded when blood flow was lower or higher than normal or at oblique angles to the line of sight. In conclusion, SD-OCT scans of the vessels in the posterior pole of the eye may assist the clinical assessment of gross abnormalities of ocular blood flow, e.g. in carotid artery stenosis.

  11. Genetics in Retinal Diseases.

    Science.gov (United States)

    Riaz, Moeen; Baird, Paul N

    2016-01-01

    The phenotypic presentation of retinal diseases is typically underpinned by the presence of genetic variation represented by either polymorphic changes, mutations, copy number variations or epigenetic changes. Retinal dystrophies can broadly be divided into two forms, either monogenic (single-gene) or complex (multifactorial) diseases. Recent advances in molecular techniques such as genome-wide association studies and next-generation sequencing have revolutionized the discovery of genetic variants associated with different retinal disorders, including retinitis pigmentosa and age-related macular degeneration. Understanding the genetic profile of the disease not only helps in diagnostics but also in gene therapy, as recently shown for Leber's congenital amaurosis. Following the elucidation of many genetic features of retinal diseases, the task is now to make sense of this large amount of data to better understand as well as experimentally prove the physiological process of the retinal disease genes and the mechanisms behind the diseases. This in turn will lead to improved gene-based therapies and personalize treatments for patients. PMID:26501365

  12. Retinal Detachment: Torn or Detached Retina Treatment

    Science.gov (United States)

    ... Eyes & the Sun Eye Health News Consumer Alerts Retinal Detachment: Torn or Detached Retina Treatment Tweet A retinal ... Detached Retina Diagnosis Torn Or Detached Retina Treatment Retinal Detachment Vision Simulator Torn retina surgery Most retinal tears ...

  13. Bilateral Patching in Retinal Detachment: Fluid Mechanics and Retinal “Settling”

    OpenAIRE

    Foster, William J

    2011-01-01

    The role of vitreous traction on retinal detachment “settling” with bilateral patching has been studied computationally. Vitreous traction, induced by eye movements and suppressed with bilateral patching, creates a subretinal vacuum that promotes increased retinal detachment.

  14. Management of massive hemoptysis in pulmonary tuberculosis and bronchiectasis by bronchial arterial embolization

    International Nuclear Information System (INIS)

    Objective: To probe into the angiographic signs and the variations of bronchial arteries for pulmonary tuberculosis or bronchiectasis with massive hemoptysis. Methods: 25 patients with pulmonary tuberculosis and 15 patients suffered from bronchiectasis accompanied by massive hemoptysis were undertaken bronchial arterial embolization (BAE). All patients were embolized with gelfoam including 32 with spring coils in addition. Results: 63 arteries demonstrated angiographic signs of hemoptysis in 40 patients. The immediate stanching rate was 92.5%(37/40). The bronchopulmonary shunt formation sign shown by angiograph was the major feature of tuberculosis (P=0.0528) and the enlarged tortuous arteries in bronchiectasis were more to be demonstrated than in tuberculosis (P<0.05). Conclusions: The BAE for patients with tuberculosis ought to be performed in the smaller arteries. BAE for patients with bronchiectasis should to be taken in the trunk of arteries. (authors)

  15. Integration of retinal image sequences

    Science.gov (United States)

    Ballerini, Lucia

    1998-10-01

    In this paper a method for noise reduction in ocular fundus image sequences is described. The eye is the only part of the human body where the capillary network can be observed along with the arterial and venous circulation using a non invasive technique. The study of the retinal vessels is very important both for the study of the local pathology (retinal disease) and for the large amount of information it offers on systematic haemodynamics, such as hypertension, arteriosclerosis, and diabetes. In this paper a method for image integration of ocular fundus image sequences is described. The procedure can be divided in two step: registration and fusion. First we describe an automatic alignment algorithm for registration of ocular fundus images. In order to enhance vessel structures, we used a spatially oriented bank of filters designed to match the properties of the objects of interest. To evaluate interframe misalignment we adopted a fast cross-correlation algorithm. The performances of the alignment method have been estimated by simulating shifts between image pairs and by using a cross-validation approach. Then we propose a temporal integration technique of image sequences so as to compute enhanced pictures of the overall capillary network. Image registration is combined with image enhancement by fusing subsequent frames of a same region. To evaluate the attainable results, the signal-to-noise ratio was estimated before and after integration. Experimental results on synthetic images of vessel-like structures with different kind of Gaussian additive noise as well as on real fundus images are reported.

  16. Transient tractional retinal detachment in an eye with retinitis pigmentosa

    OpenAIRE

    Shuichiro Hirahara; Yoshio Hirano; Tsutomu Yasukawa; et al

    2010-01-01

    Shuichiro Hirahara, Yoshio Hirano, Tsutomu Yasukawa, Yuichiro OguraDepartment of Ophthalmology and Visual Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, JapanAbstract: We present a case of retinitis pigmentosa with vitreoretinal traction-associated retinal detachment. The retinal detachment was detected in the nasal periphery. No retinal breaks and no active vascular leakage were observed by fundus scopy and fluorescein angiography, respectively. However, 8 month...

  17. Retinal detachment repair - series (image)

    Science.gov (United States)

    Retinal detachments are associated with a tear or hole in the retina through which the internal fluids of ... often caused by trauma, and the risk of retinal detachment after minor trauma, such a blow to the ...

  18. Amino acids in retinitis pigmentosa

    OpenAIRE

    Singh M.

    1988-01-01

    Retinitis pigmentosa may be associated with amino acid? disorders; whether the association is incidental or consequential is not known. The present investigation on amino acids in retinitis pigmentosa indicates that the level of plasma amino acids does not differ significantly in pa-tients with retinitis pigmentosa compared to that of normal subjects, hence it has no etiological bearing.

  19. Retinal Detachment in Preeclampsia

    Directory of Open Access Journals (Sweden)

    Prado Renata Silva do

    2002-01-01

    Full Text Available Preeclampsia is an obstetric disease of unknown cause that affects approximately 5% of pregnant women. The visual system may be affected with variable intensity, being the retinal detachment a rare complication. The retinal detachment in preeclampsia is usually bilateral and serous, and its pathogenesis is related to the choroidal ischemia secondary to an intense arteriolar vasospasm. The majority of patients have complete recovery of vision with clinical management, and surgery is unnecessary. This is a case report of a 27 year old patient who developed the severe form of preeclampsia on her first pregnancy. She had progressive blurred vision, until she could see only shadows. Ophthalmic examination diagnosed spread and bilateral retinal detachment. With blood pressure control at postpartum, the patient had her retina reattached, and recovery of vision.

  20. Probabilistic retinal vessel segmentation

    Science.gov (United States)

    Wu, Chang-Hua; Agam, Gady

    2007-03-01

    Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

  1. Retinal vasoproliferative tumor

    Directory of Open Access Journals (Sweden)

    Eduardo Ferrari Marback

    2013-06-01

    Full Text Available Retinal vasoproliferative tumor is a rare disease that has capillary hemangioma as the most frequent diferential diagnosis. The tumor is considered to be of reactive nature. It can be idiophatic or secondary to other ocular diseases such as: uveitis, retinitis pigmentosa, sickle cell disease, previous surgery and retinopathy of prematurity. Lesions with no exsudation or visual decrease can be observed. Lesions that need treatment can be managed by on or more modalities such as cryotherapy, a variety of lasers, surgical excision, radiation, and antiangiogenic intravitreal injections.

  2. The blood pressure-induced diameter response of retinal arterioles decreases with increasing diabetic maculopathy

    DEFF Research Database (Denmark)

    Frederiksen, Christian Alcaraz; Jeppesen, Peter; Knudsen, Søren Tang; Poulsen, Per Løgstrup; Mogensen, Carl Erik; Bek, Toke

    2006-01-01

    BACKGROUND: The aim of the study was to compare the diameter response of retinal arterioles and retinal thickness in patients with different stages of diabetic maculopathy during an increase in the arterial blood pressure. METHODS: Four groups each consisting of 19 individuals were studied. Group A consisted of normal individuals and groups B-D consisted of type 2 diabetic patients matched for diabetes duration, age, and gender, and characterized by: Group B no retinopathy, Group C mild retinopa...

  3. Imaging polarimetry and retinal blood vessel quantification at the epiretinal membrane

    OpenAIRE

    MIURA, MASAHIRO; Elsner, Ann E.; Cheney, Michael C.; USUI, MASAHIKO; IWASAKI, TAKUYA

    2007-01-01

    We evaluated a polarimetry method to enhance retinal blood vessels masked by the epiretinal membrane. Depolarized light images were computed by removing the polarization retaining light reaching the instrument and were compared with parallel polarized light images, average reflectance images, and the corresponding images at 514 nm. Contrasts were computed for retinal vessel profiles for arteries and veins. Contrasts were higher in the 514 nm images in normal eyes but higher in the depolarized...

  4. Empirical description of bronchial and nonbronchial arteries with MDCT

    International Nuclear Information System (INIS)

    Purpose: We aimed to retrospectively evaluate bronchial and nonbronchial systemic arteries using multi-detector row helical computed tomographic (MDCT) angiography in patients with pulmonary disorders. Materials and Methods: Thirty-nine patients (24 men, 15 women; mean age, 63.4 years; range, 20-82 years) with congenital and acquired pulmonary disorders of the bronchial and nonbronchial systemic arteries underwent multi-detector row helical computed tomographic angiography of the thorax using a 16-detector row scanner. Each of these patients had experienced an episode of hemoptysis. Computed tomographic angiogram data, which included maximum intensity projections, multiplanar reconstruction, and three-dimensional volume-rendered images, were used to retrospectively analyse the characteristics of the bronchial and nonbronchial systemic arteries. Results: We identified a total of 128 bronchial arteries (76 on the right side and 52 on the left) in 39 patients. We detected 42 nonbronchial systemic artery branches, including 19 internal mammary artery branches, 8 subclavian artery branches, 8 inferior phrenic artery branches, 5 intercostal artery branches, 1 thyrocervical trunk branch, and 1 celiac trunk branch. Thirty-five dilated and tortuous nonbronchial systemic arteries entered into the lung parenchyma and extended down to the lesions. Every case, except the one case of sequestration, was associated with pleural thickening where the vascular structures passed through the extrapleural fat. Conclusions: The variations in both the bronchial artery anatomy and the location and type of the nonbronchial arteries were great. Nonbronchial arteries may be a significant source of hemoptysis. MDCT angiography can be used to detect detailed anatomical information about the origins and courses of bronchial and nonbronchial systemic arteries and their pathophysiologic features.

  5. Empirical description of bronchial and nonbronchial arteries with MDCT

    Energy Technology Data Exchange (ETDEWEB)

    Yu Hong, E-mail: yuhong.2002@hotmail.co [Department of Imageology, Changzheng hospital, Second Military Medical University, Shanghai 200003 (China); Liu Shiyuan, E-mail: cjr.liushiyuan@vip.163.co [Department of Imageology, Changzheng hospital, Second Military Medical University, Shanghai 200003 (China); Li Huimin, E-mail: yuhongphd@163.co [Department of Imageology, Changzheng hospital, Second Military Medical University, Shanghai 200003 (China); Xiao Xiangsheng, E-mail: cjr.xxsh@vip.163.co [Department of Imageology, Changzheng hospital, Second Military Medical University, Shanghai 200003 (China); Dong Weihua, E-mail: dongweihua2000@163.co [Department of Imageology, Changzheng hospital, Second Military Medical University, Shanghai 200003 (China)

    2010-08-15

    Purpose: We aimed to retrospectively evaluate bronchial and nonbronchial systemic arteries using multi-detector row helical computed tomographic (MDCT) angiography in patients with pulmonary disorders. Materials and Methods: Thirty-nine patients (24 men, 15 women; mean age, 63.4 years; range, 20-82 years) with congenital and acquired pulmonary disorders of the bronchial and nonbronchial systemic arteries underwent multi-detector row helical computed tomographic angiography of the thorax using a 16-detector row scanner. Each of these patients had experienced an episode of hemoptysis. Computed tomographic angiogram data, which included maximum intensity projections, multiplanar reconstruction, and three-dimensional volume-rendered images, were used to retrospectively analyse the characteristics of the bronchial and nonbronchial systemic arteries. Results: We identified a total of 128 bronchial arteries (76 on the right side and 52 on the left) in 39 patients. We detected 42 nonbronchial systemic artery branches, including 19 internal mammary artery branches, 8 subclavian artery branches, 8 inferior phrenic artery branches, 5 intercostal artery branches, 1 thyrocervical trunk branch, and 1 celiac trunk branch. Thirty-five dilated and tortuous nonbronchial systemic arteries entered into the lung parenchyma and extended down to the lesions. Every case, except the one case of sequestration, was associated with pleural thickening where the vascular structures passed through the extrapleural fat. Conclusions: The variations in both the bronchial artery anatomy and the location and type of the nonbronchial arteries were great. Nonbronchial arteries may be a significant source of hemoptysis. MDCT angiography can be used to detect detailed anatomical information about the origins and courses of bronchial and nonbronchial systemic arteries and their pathophysiologic features.

  6. A semi-automated computer tool for the analysis of retinal vessel diameter dynamics.

    Science.gov (United States)

    Euvrard, Guillaume; Genevois, Olivier; Rivals, Isabelle; Massin, Pascale; Collet, Amélie; Sahel, José-Alain; Paques, Michel

    2013-06-01

    Retinal vessels are directly accessible to clinical observation. This has numerous potential interests for medical investigations. Using the Retinal Vessel Analyzer, a dedicated eye fundus camera enabling dynamic, video-rate recording of micrometric changes of the diameter of retinal vessels, we developed a semi-automated computer tool that extracts the heart beat rate and pulse amplitude values from the records. The extracted data enabled us to show that there is a decreasing relationship between heart beat rate and pulse amplitude of arteries and veins. Such an approach will facilitate the modeling of hemodynamic interactions in small vessels. PMID:23566397

  7. Retinal tolerance to dyes

    OpenAIRE

    Lüke, C; Lüke, M; Dietlein, T S; Hueber, A; Jordan, J.; Sickel, W.; Kirchhof, B

    2005-01-01

    Background: Dye solutions for intraoperative staining of epiretinal membranes and the internal limiting membrane improve the visualisation of these thin structures and facilitate their removal. In the present study the authors investigated the effects of indocyanine green 0.05%, trypan blue 0.15%, and patent blue 0.48% on bovine retinal function.

  8. Peripapillary retinal thermal coagulation following electrical injury

    Directory of Open Access Journals (Sweden)

    Manjari Tandon

    2013-01-01

    Full Text Available In this study, we have presented the case report of a 20 year old boy who suffered an electric injury shock, following which he showed peripapillary retinal opacification and increased retinal thickening that subsequently progressed to retinal atrophy. The fluorescein angiogram revealed normal retinal circulation, thus indicating thermal damage to retina without any compromise to retinal circulation.

  9. Influence of cataract surgery and blood pressure changes caused by sodium restriction on retinal vascular diameter

    Directory of Open Access Journals (Sweden)

    Takatoshi Tano

    2010-11-01

    Full Text Available Takatoshi Tano1, Yoshimune Hiratsuka2, Koichi Ono1, Akira Murakami11Department of Ophthalmology, Juntendo University School of Medicine, Tokyo; 2National Institute of Public Health, Tokyo, JapanPurpose: To investigate the impact of cataract surgery and blood pressure changes induced by one week of sodium restriction on retinal vascular diameter.Methods: Fundus photographs of 200 patients were obtained before and one week after cataract surgery. For one week after admission, 100 patients received sodium restriction and 100 patients (ie, the control group did not receive sodium restriction. The diameter of the retinal vessels and blood pressure were compared between the sodium restriction group and the control group. The vascular diameter was measured using an objective computer-based method.Results: Neither group had a significant change in the diameter of the retinal vessels after cataract surgery. Although there was no significant change in retinal arterial and venular diameter in the sodium restriction group, one-week sodium restriction significantly reduced mean blood pressure. However, multiple linear regression analyses indicated that an increase in retinal arteriolar diameter was significantly associated with diabetes, hyperlipidemia, and alcohol intake.Conclusion: Cataract surgery and blood pressure reduction induced by one week of sodium restriction resulted in no significant change in retinal arteriolar diameter.Keywords: cataract surgery, hypertension, retinal blood vessel diameter, retinal fundus camera, sodium restriction.

  10. Automated method for the identification and analysis of vascular tree structures in retinal vessel network

    Science.gov (United States)

    Joshi, Vinayak S.; Garvin, Mona K.; Reinhardt, Joseph M.; Abramoff, Michael D.

    2011-03-01

    Structural analysis of retinal vessel network has so far served in the diagnosis of retinopathies and systemic diseases. The retinopathies are known to affect the morphologic properties of retinal vessels such as course, shape, caliber, and tortuosity. Whether the arteries and the veins respond to these changes together or in tandem has always been a topic of discussion. However the diseases such as diabetic retinopathy and retinopathy of prematurity have been diagnosed with the morphologic changes specific either to arteries or to veins. Thus a method describing the separation of retinal vessel trees imaged in a two dimensional color fundus image may assist in artery-vein classification and quantitative assessment of morphologic changes particular to arteries or veins. We propose a method based on mathematical morphology and graph search to identify and label the retinal vessel trees, which provides a structural mapping of vessel network in terms of each individual primary vessel, its branches and spatial positions of branching and cross-over points. The method was evaluated on a dataset of 15 fundus images resulting into an accuracy of 92.87 % correctly assigned vessel pixels when compared with the manual labeling of separated vessel trees. Accordingly, the structural mapping method performs well and we are currently investigating its potential in evaluating the characteristic properties specific to arteries or veins.

  11. Retinal Detachment: Torn or Detached Retina Diagnosis

    Science.gov (United States)

    ... Eyes & the Sun Eye Health News Consumer Alerts Retinal Detachment: Torn or Detached Retina Diagnosis Tweet Your ophthalmologist can diagnose retinal tear or retinal detachment during an eye examination where he or she ...

  12. Retinal Detachment: Torn or Detached Retina Symptoms

    Science.gov (United States)

    ... Eyes & the Sun Eye Health News Consumer Alerts Retinal Detachment: Torn or Detached Retina Symptoms Tweet Symptoms of a retinal tear and a retinal detachment can include the following: • A sudden increase in ...

  13. Contrast sensitivity in retinitis pigmentosa.

    OpenAIRE

    Lindberg, C. R.; Fishman, G.A.; R.J. Anderson; Vasquez, V.

    1981-01-01

    Arden gratings were used to measure contrast sensitivity in 40 patients with retinitis pigmentosa whose Snellen visual acuity was 6/12 or better. When compared with a group of 30 normal subjects the patients with retinitis pigmentosa had substantially decreased contrast sensitivity, especially at high frequencies. The Arden grating test appeared to be a sensitive test of abnormal central visual function in patients with retinitis pigmentosa.

  14. Inherited Retinal Degenerative Disease Registry

    Science.gov (United States)

    2015-05-01

    Eye Diseases Hereditary; Retinal Disease; Achromatopsia; Bardet-Biedl Syndrome; Bassen-Kornzweig Syndrome; Batten Disease; Best Disease; Choroidal Dystrophy; Choroideremia; Cone Dystrophy; Cone-Rod Dystrophy; Congenital Stationary Night Blindness; Enhanced S-Cone Syndrome; Fundus Albipunctatus; Goldmann-Favre Syndrome; Gyrate Atrophy; Juvenile Macular Degeneration; Kearns-Sayre Syndrome; Leber Congenital Amaurosis; Refsum Syndrome; Retinitis Pigmentosa; Retinitis Punctata Albescens; Retinoschisis; Rod-Cone Dystrophy; Rod Dystrophy; Rod Monochromacy; Stargardt Disease; Usher Syndrome

  15. Optogenetic approaches to retinal prosthesis

    OpenAIRE

    BARRETT, JOHN MARTIN; Berlinguer-Palmini, Rolando; DEGENAAR, PATRICK

    2014-01-01

    The concept of visual restoration via retinal prosthesis arguably started in 1992 with the discovery that some of the retinal cells were still intact in those with the retinitis pigmentosa disease. Two decades later, the first commercially available devices have the capability to allow users to identify basic shapes. Such devices are still very far from returning vision beyond the legal blindness. Thus, there is considerable continued development of electrode materials, and ...

  16. Intra-arterial chemotherapy for bilateral retinoblastoma via left ophthalmic artery and right anterior deep temporal artery.

    Science.gov (United States)

    Amans, Matthew R; Narvid, Jared; Halbach, Van V

    2014-01-01

    A 12-month-old boy with a history of bilateral retinoblastoma refractory to systemic chemotherapy, laser therapy and cryotherapy, with excellent response to previous intra-arterial melphalan infusion, presents with active tumour deposits in the right eye. Repeat intra-arterial chemotherapy was recommended. Previous bilateral melphalan infusion was uneventful using flow-guided catheterisation technique. Direct catheterisation of the right ophthalmic artery was unsuccessful despite employment of several flow-guided and over-the-wire catheters. Superselective catheterisation of the ipsilateral middle meningeal artery was unable to identify an anastomotic connection to the ophthalmic artery; however, angiography of the anterior deep temporal artery identified an alternate route for chemotherapy infusion. The anterior deep temporal artery was successfully and safely catheterised to infuse chemotherapy into the ophthalmic artery. The anterior deep temporal artery is an important potential anastomotic connection to the ophthalmic artery that can be used safely and effectively for central retinal artery chemotherapy infusion for retinoblastoma treatment. PMID:25240013

  17. Optogenetics for Retinal Disorders

    OpenAIRE

    Henriksen, Bradley S; Marc, Robert E; Bernstein, Paul S

    2014-01-01

    Optogenetics is the use of genetic methods combined with optical technology to achieve gain or loss of function within neuronal circuits. The field of optogenetics has been rapidly expanding in efforts to restore visual function to blinding diseases such as retinitis pigmentosa (RP). Most work in the field includes a group of light-sensitive retinaldehyde-binding proteins known as opsins. Opsins couple photon absorption to molecular signaling chains that control cellular ion currents. Targeti...

  18. Neuroprotection and Retinal Diseases.

    Science.gov (United States)

    Paulus, Yannis M; Campbell, J Peter

    2016-01-01

    Neuronal death is the primary cause of vision loss in most retinal diseases. Neuroprotection is the modification of neurons, and/or their surrounding environment, to promote the survival and function of the neurons, especially in environments that would normally be deleterious to their health. Through advances in antioxidative therapy, neurotrophic support and anti-apoptotic therapy, the field of neuroprotection is advancing with the therapeutic hope of improving vision and clinical outcomes for patients. PMID:26501142

  19. Lessons from retinal dystrophins

    Directory of Open Access Journals (Sweden)

    Michel Joseph Roux

    2013-01-01

    Full Text Available Problem Statement: Dystrophins are expressed not only in muscles, but also in many parts of the central nervous system, including the cerebellum, hippocampus and retina. This leads in many Duchenne patients to cognitive deficits, as well as an abnormal electroretinogram, close to the one found in night-blind patients. This latter element is puzzling, as patients do not seem to suffer from visual deficits. This has attracted attention to retinal dystrophins, which are expressed in Müller glial cells (Dp71, notably in the processes surrounding blood vessels, and in photoreceptors and possibly in bipolar and/or amacrine cells (Dp427, Dp260 and Dp140. We have examined how the absence of these proteins lead to an abnormal electroretinogram, and if Dp71 absence impacted the bloor-retinal-barrier integrity. Approach: Comparison of the mdx3Cv (which lacks all dystrophins and/or Dp71-null mice to WT was performed by immunohistochemistry and confocal microscopy, as well as by electron microscopy. Results: Absence of Dp71 alters the blood-retinal barrier integrity and leads to an abnormal development of retinal vessels. When longer dystrophins are missing (mdx3Cv mouse, the morphology of the synapse between photoreceptors and bipolar cells is profoundly altered. In addition, the distribution of proteins involved in calcium signaling in bipolar cells is modified in mdx3Cv but not Dp71-null retinas. Conclusion: Together, these results stress the fragility of Duchenne retina in absence of Dp71, and open new perspectives to understand not only the abnormal electroretinography in Duchenne patients, but also possibly their cognitive deficits.

  20. Retinal vasculature enhancement using independent component analysis

    OpenAIRE

    Ahmad Fadzil M. Hani; Hanung Adi Nugroho

    2009-01-01

    Retinal vasculature is a network of vessels in the retinal layer. In ophthalmology, information of retinal vasculature in analyzing fundus images is important for early detection of diseases related to the retina, e.g. diabetic retinopathy. However, in fundus images the contrast between retinal vasculature and the background is very low. As a result, analyzing or visualizing tiny retinal vasculature is difficult. There-fore, enhancement of retinal vasculature in digital fundus image is import...

  1. Retinal oxygen extraction in humans

    Science.gov (United States)

    Werkmeister, René M.; Schmidl, Doreen; Aschinger, Gerold; Doblhoff-Dier, Veronika; Palkovits, Stefan; Wirth, Magdalena; Garhöfer, Gerhard; Linsenmeier, Robert A.; Leitgeb, Rainer A.; Schmetterer, Leopold

    2015-10-01

    Adequate function of the retina is dependent on proper oxygen supply. In humans, the inner retina is oxygenated via the retinal circulation. We present a method to calculate total retinal oxygen extraction based on measurement of total retinal blood flow using dual-beam bidirectional Doppler optical coherence tomography and measurement of oxygen saturation by spectrophotometry. These measurements were done on 8 healthy subjects while breathing ambient room air and 100% oxygen. Total retinal blood flow was 44.3?±?9.0??l/min during baseline and decreased to 18.7?±?4.2??l/min during 100% oxygen breathing (P?diabetic retinopathy.

  2. Retinal Thickening and Photoreceptor Loss in HIV Eyes without Retinitis

    Science.gov (United States)

    Arcinue, Cheryl A.; Bartsch, Dirk-Uwe; El-Emam, Sharif Y.; Ma, Feiyan; Doede, Aubrey; Sharpsten, Lucie; Gomez, Maria Laura; Freeman, William R.

    2015-01-01

    Purpose To determine the presence of structural changes in HIV retinae (i.e., photoreceptor density and retinal thickness in the macula) compared with age-matched HIV-negative controls. Methods Cohort of patients with known HIV under CART (combination Antiretroviral Therapy) treatment were examined with a flood-illuminated retinal AO camera to assess the cone photoreceptor mosaic and spectral-domain optical coherence tomography (SD-OCT) to assess retinal layers and retinal thickness. Results Twenty-four eyes of 12 patients (n = 6 HIV-positive and 6 HIV-negative) were imaged with the adaptive optics camera. In each of the regions of interest studied (nasal, temporal, superior, inferior), the HIV group had significantly less mean cone photoreceptor density compared with age-matched controls (difference range, 4,308–6,872 cones/mm2). A different subset of forty eyes of 20 patients (n = 10 HIV-positive and 10 HIV-negative) was included in the retinal thickness measurements and retinal layer segmentation with the SD-OCT. We observed significant thickening in HIV positive eyes in the total retinal thickness at the foveal center, and in each of the three horizontal B-scans (through the macular center, superior, and inferior to the fovea). We also noted that the inner retina (combined thickness from ILM through RNFL to GCL layer) was also significantly thickened in all the different locations scanned compared with HIV-negative controls. Conclusion Our present study shows that the cone photoreceptor density is significantly reduced in HIV retinae compared with age-matched controls. HIV retinae also have increased macular retinal thickness that may be caused by inner retinal edema secondary to retinovascular disease in HIV. The interaction of photoreceptors with the aging RPE, as well as possible low-grade ocular inflammation causing diffuse inner retinal edema, may be the key to the progressive vision changes in HIV-positive patients without overt retinitis. PMID:26244973

  3. Segmental reproducibility of retinal blood flow velocity measurements using retinal function imager

    Science.gov (United States)

    Chhablani, Jay; Bartsch, Dirk-Uwe; Kozak, Igor; Cheng, Lingyun; Alshareef, Rayan A; Rezeq, Sami S; Sampat, Kapil M; Garg, Sunir J; Burgansky-Eliash, Zvia; Freeman, William R

    2013-01-01

    Background To evaluate the reproducibility of blood flow velocity measurements of individual retinal blood vessel segments using retinal function imager (RFI). Methods Eighteen eyes of 15 healthy subjects were enrolled prospectively at three centers. All subjects underwent RFI imaging in two separate sessions 15 min apart by a single experienced photographer at each center. An average of five to seven serial RFI images were obtained. All images were transferred electronically to one center, and were analyzed by a single observer. Multiple blood vessel segments (each shorter than 100 ?m) were co-localized on first and second session images taken at different times of the same fundus using built-in software. Velocities of corresponding segments were determined, and then the inter-session reproducibility of flow velocity was assessed by the concordance correlation co-efficient (CCC), coefficient of reproducibility (CR), and coefficient of variance (CV). Results Inter-session CCC for flow velocity was 0.97 (95% confidence interval (CI), 0.966 to 0.9797). The CR was 1.49 mm/sec (95% CI, 1.39 to 1.59 mm/sec), and CV was 10.9%. The average arterial blood flow velocity was 3.16 mm/sec, and average venous blood flow velocity was 3.15 mm/sec. The CR for arterial and venous blood flow velocity was 1.61 mm/sec and 1.27 mm/sec respectively. Conclusion RFI provides reproducible measurements for retinal blood flow velocity for individual blood vessel segments, with 10.9% variability. PMID:23700326

  4. Bilateral Carotid and Vertebral Rete Mirabile Presenting with a Prominent Anterior Spinal Artery Mimicking a Spinal Dural AV Fistula at MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Young; Cha, Sang Hoon [Chungbuk National University College of Medicine, Iksan (Korea, Republic of)

    2011-11-15

    Bilateral carotid and vertebral rete mirabile (CVRM) is a very rare condition. We report a new case of CVRM initially detected by magnetic resonance imaging (MRI) of the cervical spine. MRI demonstrated tortuous vascular signal voids limited to the anterior cerebrospinal fluid space mimicking spinal dural arteriovenous fistula. A diagnosis of CVRM was confirmed on the basis of angiographic findings of rete formation associated with bilateral aplasia of the cavernous internal carotid and vertebral arteries without abnormal arteriovenous connection.

  5. Bilateral Carotid and Vertebral Rete Mirabile Presenting with a Prominent Anterior Spinal Artery Mimicking a Spinal Dural AV Fistula at MRI

    International Nuclear Information System (INIS)

    Bilateral carotid and vertebral rete mirabile (CVRM) is a very rare condition. We report a new case of CVRM initially detected by magnetic resonance imaging (MRI) of the cervical spine. MRI demonstrated tortuous vascular signal voids limited to the anterior cerebrospinal fluid space mimicking spinal dural arteriovenous fistula. A diagnosis of CVRM was confirmed on the basis of angiographic findings of rete formation associated with bilateral aplasia of the cavernous internal carotid and vertebral arteries without abnormal arteriovenous connection.

  6. Refractile superficial retinal crystals and chronic retinal detachment: Case report

    Directory of Open Access Journals (Sweden)

    McCarthy John H

    2006-01-01

    Full Text Available Abstract Background Few previous reports have described the presence of retinal refractile opacities at the macular area in patients presenting with longstanding peripheral retinal detachment. The exact nature of these opacities is unknown. Case presentation Two patients were referred with an abnormal appearance of refractile opacities in the macular area noted during routine examination. Both were found to have longstanding peripheral retinal detachments. Subretinal fluid analysis of one patient revealed the presence of multiple birefringent crystals. We hypothesise that these crystals are the origin of the refractile macular opacities noted. Conclusion This report describes the rare presentation of asymptomatic peripheral retinal detachment by the detection of refractile macular opacities on routine examination. It highlights the importance of meticulous peripheral retinal examination in these cases. The article also describes the findings of the subretinal fluid analysis and discusses the possible hypothesis behind their appearance.

  7. Descolamento de retina seroso em paraganglioma: relato de caso / Serous retinal detachment in paraganglioma: case report

    Scientific Electronic Library Online (English)

    Oscar, Villas Boas; André Moura, Bastos; Alexandre Campelo, Ramiro; Roberto Alexandre, Fonseca.

    2008-02-01

    Full Text Available Os autores descrevem um caso de uma paciente gestante com hipertensão arterial resistente ao tratamento e descolamento seroso bilateral de retina. Confirmou-se, pelo exame anátomo-patológico, ser um paraganglioma. [...] Abstract in english The authors describe a case of a pregnant patient with arterial hypertension that resists to the treatment and retinal bilateral serous detachment. It was confirmed to be a paraganglioma by anatomicopathological examination. [...

  8. Descolamento de retina seroso em paraganglioma: relato de caso Serous retinal detachment in paraganglioma: case report

    Directory of Open Access Journals (Sweden)

    Oscar Villas Boas

    2008-02-01

    Full Text Available Os autores descrevem um caso de uma paciente gestante com hipertensão arterial resistente ao tratamento e descolamento seroso bilateral de retina. Confirmou-se, pelo exame anátomo-patológico, ser um paraganglioma.The authors describe a case of a pregnant patient with arterial hypertension that resists to the treatment and retinal bilateral serous detachment. It was confirmed to be a paraganglioma by anatomicopathological examination.

  9. Pharmacotherapy of Retinal Diseases with Ranibizumab

    Directory of Open Access Journals (Sweden)

    Daniel F. Kiernan

    2009-01-01

    Full Text Available The development of new, abnormal and leaky blood vessels, termed choroidal neovascularization, causes loss of vision and quality of life as a result of many ocular diseases. A current therapy for a leading cause of irreversible blindness in older people in the United States, age-related macular degeneration, is intravitreal injection of ranibizumab. However, ranibizumab has also been used off-label to successfully treat a number of other ocular diseases causing significant ocular morbidity, including retinal vascular occlusion and diabetic macular edema. Despite its efficacy, the association of detectable serum levels of ranibizumab and arterial thromboembolic events in major follow-up studies since its approval by the United States Food and Drug Administration as well as its high cost relative to the possible existence of cheaper, equally efficacious alternatives has underscored the importance of understanding the mode of action and clinical utility of this novel pharmacotherapy.

  10. Prophylactic cryotherapy of retinal breaks.

    Science.gov (United States)

    Yanoff, M

    1977-03-01

    All 100 eyes treated with transconjunctival cryotherapy to seal peripheral retinal breaks had a final vision as good or better than when they were first seen. Three of the 100 eyes developed clinical retinal detachments subsequent to the initial cryotherapy, necessitating scleral buckling procedures; all 3 had a final vision of 6/6 in the involved eye. No other complications occurred. Indications for treating retinal breaks or for not treating, are presented. In general, all symptomatic retinal breaks and asymptomatic ones if in aphakic eyes, when crescentic or linear at the margin of lattice, or if horseshoe, are treated. Other instances in which asymptomatic retinal breaks are treated are the following: (1) eyes on long-term miotics: (2) cases in which a retinal detachment is present in the fellow eye: (3) the break(s) are in an only eye; (4) cataract extraction is being considered; (5) 4 diopters of myopia or greater are present; or (6) subretinal fluid of more than 1 but less than 2 disc diameters in size is noted. Other retinal breaks not associated with subclinical or clinical retinal detachments are placed under observation at periodic intervals. PMID:869411

  11. High resolution optoelectronic retinal prosthesis

    Science.gov (United States)

    Loudin, Jim; Dinyari, Rostam; Huie, Phil; Butterwick, Alex; Peumans, Peter; Palanker, Daniel

    2009-02-01

    Electronic retinal prostheses seek to restore sight in patients with retinal degeneration by delivering pulsed electric currents to retinal neurons via an array of microelectrodes. Most implants use inductive or optical transmission of information and power to an intraocular receiver, with decoded signals subsequently distributed to retinal electrodes through an intraocular cable. Surgical complexity could be minimized by an "integrated" prosthesis, in which both power and data are delivered directly to the stimulating array without any discrete components or cables. We present here an integrated retinal prosthesis system based on a photodiode array implant. Video frames are processed and imaged onto the retinal implant by a video goggle projection system operating at near-infrared wavelengths (~ 900 nm). Photodiodes convert light into pulsed electric current, with charge injection maximized by specially optimized series photodiode circuits. Prostheses of three different pixel densities (16 pix/mm2, 64 pix/mm2, and 256 pix/mm2) have been designed, simulated, and prototyped. Retinal tissue response to subretinal implants made of various materials has been investigated in RCS rats. The resulting prosthesis can provide sufficient charge injection for high resolution retinal stimulation without the need for implantation of any bulky discrete elements such as coils or tethers. In addition, since every pixel functions independently, pixel arrays may be placed separately in the subretinal space, providing visual stimulation to a larger field of view.

  12. Persistent trigeminal artery variants detected by MR angiography

    International Nuclear Information System (INIS)

    Persistent trigeminal artery (PTA) variants are cerebellar arteries that originate directly from the precavernous portion of the internal carotid artery (ICA). The goal of our study was to determine the incidence and MR angiographic features of PTA variants. Between April 1996 and September 1999, 523 cranial MR angiographies were performed at our institution. Most of the patients examined had or were suspected of having cerebrovascular disease. We retrospectively reviewed these 523 MR angiograms. A 1.5-T scanner was used in all studies, and maximum intensity projection (MIP) images obtained using the three-dimensional time-of-flight (3D TOF) technique were displayed stereoscopically. Four PTA variants were detected on MR angiograms, at a rate of 0.76 %. At least three of the four PTA variants were anterior inferior cerebellar arteries (AICAs), small tortuous arteries arising from the precavernous portions of the ICAs and taking a posterior course. Although the clinical significance is not great, we found a relatively high incidence of PTA variants on MR angiograms. We stress that knowledge and recognition of these anomalous cerebellar arteries are useful and important in the interpretation of cranial MR angiograms. (orig.)

  13. Flow patterns on spectral-domain optical coherence tomography reveal flow directions at retinal vessel bifurcations

    DEFF Research Database (Denmark)

    Willerslev, Anne; Li, Xiao Q; Munch, Inger C; Larsen, Michael

    2014-01-01

    PURPOSE: To study intravascular characteristics of flowing blood in retinal vessels using spectral-domain optical coherence tomography (SD-OCT). METHODS: Examination of selected arterial bifurcations and venous sites of confluence in 25 healthy 11-year-old children recruited as an ad hoc subsampl...... determined using SD-OCT. This feature may assist the identification of flow reversal near sites of vascular occlusion, the analysis of blood flow near vascular malformations and the segmentation of retinal SD-OCT images.......PURPOSE: To study intravascular characteristics of flowing blood in retinal vessels using spectral-domain optical coherence tomography (SD-OCT). METHODS: Examination of selected arterial bifurcations and venous sites of confluence in 25 healthy 11-year-old children recruited as an ad hoc subsample...... from the population-based, observational Copenhagen Child Cohort 2000 study. RESULTS: The blood stream in retinal arteries maintains a figure-of-8 SD-OCT profile consistent with a laminar flow in concentric sheets and a parabolic velocity distribution up to the point of divergence at arterial...

  14. Gelatine and hydroxyl ethyl starch hypervolemic hemodilution – Effect on hemorheology and retinal circulation in a pig model

    OpenAIRE

    Grossherr, M; Hager, A; Gerriets, T; E. G. Kraatz; Misfeld, M.; K. F. Klotz

    2008-01-01

    The present study was designed to determine the effects of hemodilution with gelatine (GEL) and hydroxyethyl starch (HES) on hematocrit, blood viscosity, systemic hemodynamics, and central retinal arterial blood flow in anaesthetized pigs. 20 pigs were studied. Hypervolemic hemodilution was induced by 30 ml kg-1h-1 GEL (n=10) or HES (n=10) infused over 30 min. The hematocrit decreased comparably in both groups. Plasma viscosity was higher after HES than after GEL. Systolic central retinal blo...

  15. Retinal oxygen saturation evaluation by multi-spectral fundus imaging

    Science.gov (United States)

    Khoobehi, Bahram; Ning, Jinfeng; Puissegur, Elise; Bordeaux, Kimberly; Balasubramanian, Madhusudhanan; Beach, James

    2007-03-01

    Purpose: To develop a multi-spectral method to measure oxygen saturation of the retina in the human eye. Methods: Five Cynomolgus monkeys with normal eyes were anesthetized with intramuscular ketamine/xylazine and intravenous pentobarbital. Multi-spectral fundus imaging was performed in five monkeys with a commercial fundus camera equipped with a liquid crystal tuned filter in the illumination light path and a 16-bit digital camera. Recording parameters were controlled with software written specifically for the application. Seven images at successively longer oxygen-sensing wavelengths were recorded within 4 seconds. Individual images for each wavelength were captured in less than 100 msec of flash illumination. Slightly misaligned images of separate wavelengths due to slight eye motion were registered and corrected by translational and rotational image registration prior to analysis. Numerical values of relative oxygen saturation of retinal arteries and veins and the underlying tissue in between the artery/vein pairs were evaluated by an algorithm previously described, but which is now corrected for blood volume from averaged pixels (n > 1000). Color saturation maps were constructed by applying the algorithm at each image pixel using a Matlab script. Results: Both the numerical values of relative oxygen saturation and the saturation maps correspond to the physiological condition, that is, in a normal retina, the artery is more saturated than the tissue and the tissue is more saturated than the vein. With the multi-spectral fundus camera and proper registration of the multi-wavelength images, we were able to determine oxygen saturation in the primate retinal structures on a tolerable time scale which is applicable to human subjects. Conclusions: Seven wavelength multi-spectral imagery can be used to measure oxygen saturation in retinal artery, vein, and tissue (microcirculation). This technique is safe and can be used to monitor oxygen uptake in humans. This work is original and is not under consideration for publication elsewhere.

  16. Clinical features and etiology of retinal vasculitis in Northern Thailand

    Directory of Open Access Journals (Sweden)

    Supanut Apinyawasisuk

    2013-01-01

    Full Text Available Purpose: To report on the clinical features and etiology of patients with retinal vasculitis (RV. Materials and Methods: We reviewed medical records of 47 patients (75 affected eyes diagnosed with RV. Clinical presentations, ocular complications, associated systemic diseases, and treatment regimens were registered. Results: Etiology of RV included infectious causes in 10/47, (21% while an association with systemic and/or ocular non-infectious disorders was noted in 22/47 (47%. Eales? disease and Behcet?s disease represented the most common clinical entities in non-infectious group while tuberculosis-associated RV was diagnosed in 6/10 (60% among those with infectious disorders. RV was bilateral in 28/47 (60% patients. Retinal veins were most commonly affected (72%, 34/47. Involvement of arteries was present in 12/47 (25% and was associated with viral infections and Behcet?s disease. Ocular complications developed in 60/75 (80% eyes. The most common complications were elevated intraocular pressure and/or glaucoma (33/75, 44%. Retinal detachment, vitreous hemorrhage, and cystoid macular edema developed in similar percentages (15%. Conclusions: RV in Thailand manifested mostly in male patients, was typically bilateral and involved mostly veins. Involvement of arteries was observed in patients with viral infections and Behcet?s disease. Tuberculosis was the most common infectious cause.

  17. Predetection of diseases by retinal diagnosis using Digital image processing.

    Directory of Open Access Journals (Sweden)

    Vamsi Krishna Reddy Munnangi#1 , Hemanth yadav Aradhyula#2 , Riyan Mohammed

    2013-08-01

    Full Text Available This paper presents linguistic process for detecting the risk of future heart strokes and various diseases using the retinal image. For patients, it can be reduced the need for travel and provide the access to a doctor. Ophthalmology lends itself easily to telemedicine as it’s a largely image based diagnosis to know the disease of a person earlier. The main goal of the proposed system is to diagnose the type of disease by the retinal image and to automatically detect and segment retinal diseases/various diseases in human beings without human supervision or interaction. The eyes are one place in the body through which we can actually see veins and arteries without surgery and without X-rays. The eyes also reveal the disease present in the human body like high blood pressure, diabetes and future risk of heart strokes. Hence a retina scan can provide sufficient results to predict risk of heart attack and other diseases. So we can use retinal image analysis to analyze whether a person is having high blood pressure,diabetes,crop disease by detecting crossovers and diameter of blood vessels in retina and this can be processed by the digital image processing

  18. Management of retinal detachments secondary to cytomegalovirus retinitis.

    Science.gov (United States)

    Ross, W H; Bryan, J S; Barloon, A S

    1994-06-01

    Nine patients with acquired immune deficiency syndrome underwent surgery for rhegmatogenous retinal detachments related to cytomegalovirus (CMV) retinitis. The patients were followed for at least 6 months or until death. Two patients with localized peripheral detachments for 3 to 4 clock hours or less initially underwent laser retinopexy. Although in both cases the treatment ultimately failed, one patient maintained 20/20 vision for 5 months. In four patients in whom the retinal detachment was more extensive but could be explained on the basis of a single or multiple well-defined peripheral break(s), a scleral buckle procedure was performed, with anatomic success in three, two of whom maintained 20/40 vision for 7 and 8 months. Six patients with retinal detachments associated with multiple atrophic holes that were not amenable to scleral buckling were treated with pars plana vitrectomy, air-fluid exchange and endolaser, with anatomic success in three; the visual acuity ranged from 20/30 to 20/400. One patient with failed pars plana vitrectomy underwent repeat vitrectomy with long-term internal tamponade by silicone oil, and he regained hand movements vision. We suggest a graduated approach to the management of retinal detachments secondary to CMV retinitis tailored to each patient based on the number and location of the retinal breaks, the extent of the detachment, the extent of necrotic retina and the overall health of the patient. PMID:7922852

  19. Retinal hemodynamic oxygen reactivity assessed by perfusion velocity, blood oximetry and vessel diameter measurements

    DEFF Research Database (Denmark)

    Klefter, Oliver Niels; Lauritsen, Anne Øberg

    2015-01-01

    PURPOSE: To test the oxygen reactivity of a fundus photographic method of measuring macular perfusion velocity and to integrate macular perfusion velocities with measurements of retinal vessel diameters and blood oxygen saturation. METHODS: Sixteen eyes in 16 healthy volunteers were studied at two examination sessions using motion-contrast velocimetry and retinal oximetry with vessel diameter corrections. To test oxygen reactivity, participants were examined during normoxia, after 15 min of hyperoxia and finally after 45 min of normoxia. Repeatability was assessed by intraclass correlation coefficients (ICC) and limits of agreement. RESULTS: Fifteen minutes of hyperoxia was accompanied by mean reductions in arterial and venous perfusion velocities of 14% and 16%, respectively (p = 0.0080; p = 0.0019), constriction of major arteries and veins by 5.5% and 8.2%, respectively (p < 0.0001), increased retinal arterial oxygen saturation from 95.1 ± 5.0% to 96.6 ± 6.4% (p = 0.038) and increased retinal venous oxygen saturation from 62.9 ± 6.7% to 70.3 ± 7.8% (p = 0.0010). Parameters returned to baseline levels after subsequent normoxia. Saturation and vessel diameter ICCs were 0.88-0.98 (range). For perfusion velocities, short-term ICCs were 0.79-0.82 and long-term ICCs were 0.06-0.11. Intersession increases in blood glucose were associated with reductions in perfusion velocities (arterial p = 0.0067; venous p = 0.018). CONCLUSION: Oxygen reactivity testing supported that motion-contrast velocimetry is a valid method for assessing macular perfusion. Results were consistent with previous observations of hyperoxic blood flow reduction using blue field entoptic and laser Doppler velocimetry. Retinal perfusion seemed to be regulated around individual set points according to blood glucose levels. Multimodal measurements may provide comprehensive information about retinal metabolism.

  20. Clinical observation of systemic lupus erythematosus complicated with major retinal vascular occlusion

    Directory of Open Access Journals (Sweden)

    Qiao Chen

    2015-12-01

    Full Text Available AIM:To observe the clinical characteristics of the patients with systemic lupus erythematosus(SLEcomplicated with major retinal vascular occlusion.METHODS:Seventeen patients(21 eyeswith SLE complicated with major retinal vascular occlusion were selected as the experimental group from January 2010 to January 2014 in our hospital. Thirty cases(60 eyesof SLE patients without retinopathy were selected as the control group. Ocular and systemic examination and related laboratory tests, including various autoimmune antibodies, were taken. Clinical symptoms and signs were recorded.RESULTS:In the experimental group, 13 cases were uniocular, 4 cases were bilocular, in which there were central retinal vein occlusion(CRVOin 7 eyes(33%, branch retinal vein occlusion(BRVOin 9 eyes(43%, central retinal artery occlusion(CRAOin 3 eyes(14%,branch retinal artery occlusion(BRAOin 1 eye(5%,CRAO combined with CRVO in 1 eye(5%. The best corrected visual acuity(BCVAof the experimental group was significantly worse than that of the control group. The incidence of skin erythema(76%, fever(59%, arthritis(53%, central nervous system symptoms(headache and neuropsychiatric abnormalities(76%, pleurisy(41%were significantly higher than those of the control group. The positive rate of anti ds-DNA antibody(100%and antiphospholipid antibody(65%, the decrease of C3(82%, the elevation of erythrocyte sedimentation rate(100%, thrombocytopenia(65%were significantly higher than those of the control group. The score of SLEDAI(systemic lupus erythematosus disease activity indexwas 20.24±4.66 prompting SLE in moderate or severe active stage.CONCLUSION:In SLE patients with major retinal vascular occlusion, the visual acuity was severely damaged, the multi-system was affected in varying degrees, and all of the patients were in moderate and severe activity period. There may be a correlation between retinal vascular occlusion, APA, and central nervous system disease in SLE.

  1. Retinal vessel diameters and their correlation with retinal nerve fiber layer thickness in patients with pseudoexfoliation syndrome

    Directory of Open Access Journals (Sweden)

    Mehmet Cuneyt Ozmen

    2015-04-01

    Full Text Available AIM: To compare retinal artery-vein diameters (RAVDs of patients with pseudoexfoliation (PSX syndrome with healthy controls and investigate the correlations between retinal nerve fiber layer (RNFL thickness parameters and RAVDs. METHODS: Seventeen eyes with PSX and 17 eyes of age-matched controls were included in the study. All participants underwent routine ophthalmological examination, Humphrey visual field and RNFL examination by using Stratus OCT. Retinal images were obtained by using a retinal camera (Topcon 501X. RAVDs were measured from inferior nasal, inferior temporal, superior nasal and superior temporal arcuates by using IMAGEnet software. Superior, inferior, nasal, temporal and average RNFL thicknesses were recorded. RAVDs and RNFL parameters in groups and correlations were analyzed by Mann-Whitney U and Spearmann correlation tests. RESULTS: Only inferior quadrant and average RNFL thickness were detected thinner in the PSX group compared with control group (P=0.009, P=0.038, respectively. No statistically significant difference regarding RAVDs was found between two groups. CONCLUSION: RAVDs seems to be comparable in the PSX and control group. RNFL is thinner in the inferior quadrant in the PSX group. RNFL thickness and RAVDs show significant correlations in both groups. This correlation doesn’t seem to be specific to PSX.

  2. Gelatine and hydroxyl ethyl starch hypervolemic hemodilution – Effect on hemorheology and retinal circulation in a pig model

    Directory of Open Access Journals (Sweden)

    M. Grossherr

    2008-04-01

    Full Text Available The present study was designed to determine the effects of hemodilution with gelatine (GEL and hydroxyethyl starch (HES on hematocrit, blood viscosity, systemic hemodynamics, and central retinal arterial blood flow in anaesthetized pigs. 20 pigs were studied. Hypervolemic hemodilution was induced by 30 ml kg-1h-1 GEL (n=10 or HES (n=10 infused over 30 min. The hematocrit decreased comparably in both groups. Plasma viscosity was higher after HES than after GEL. Systolic central retinal blood flow and resistance index increased and were higher after HES than after GEL. Despite a greater plasma viscosity HES increases retinal microcirculation during hypervolemic hemodilution.

  3. Delayed administration of glial cell line-derived neurotrophic factor (GDNF) protects retinal ganglion cells in a pig model of acute retinal ischemia

    DEFF Research Database (Denmark)

    2009-01-01

    This study investigates whether intravitreal administration of glial cell line-derived neurotrophic factor (GDNF) enhances survival of NeuN positive retinal cells in a porcine model of retinal ischemia. 16 pigs were subjected to an ischemic insult where intraocular pressure was maintained at 5 mmHg below mean arterial blood pressure for 2 h. The mean IOP during the ischemic insult was 79.5 mmHg (s.e.m. 2.1 mmHg, n = 15). Three days after the insult the pigs received an intravitreal injection of ...

  4. Advances in Retinal Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Matthew Trese

    2012-01-01

    Full Text Available Retinal degenerations cause permanent visual loss and affect millions world-wide. Current treatment strategies, such as gene therapy and anti-angiogenic drugs, merely delay disease progression. Research is underway which aims to regenerate the diseased retina by transplanting a variety of cell types, including embryonic stem cells, fetal cells, progenitor cells and induced pluripotent stem cells. Initial retinal transplantation studies injected stem and progenitor cells into the vitreous or subretinal space with the hope that these donor cells would migrate to the site of retinal degeneration, integrate within the host retina and restore functional vision. Despite promising outcomes, these studies showed that the bolus injection technique gave rise to poorly localized tissue grafts. Subsequently, retinal tissue engineers have drawn upon the success of bone, cartilage and vasculature tissue engineering by employing a polymeric tissue engineering approach. This review will describe the evolution of retinal tissue engineering to date, with particular emphasis on the types of polymers that have routinely been used in recent investigations. Further, this review will show that the field of retinal tissue engineering will require new types of materials and fabrication techniques that optimize the survival, differentiation and delivery of retinal transplant cells.

  5. Sector retinitis pigmentosa in juvenile nephronophthisis.

    OpenAIRE

    Godel, V; Iaina, A.; Nemet, P.; Lazar, M.

    1980-01-01

    In a patient with juvenile nephronophthisis, sector retinitis pigmentosa was found as an extrarenal manifestation, establishing a hitherto undescribed variety of retinal degeneration occurring in this disorder. The retinal function in this case was identical with that in the classic type of sector retinitis pigmentosa, namely, subnormal ERG amplitudes but normal cone and rod implicit times. The range of the retinal findings and their autosomal recessive transmission are discussed. Paucity of ...

  6. Retinal Image Preprocessing: Background and Noise Segmentation

    OpenAIRE

    Usman Akram

    2012-01-01

    Retinal images are used for the automated screening and diagnosis of diabetic retinopathy. The retinal image quality must be improved for the detection of features and abnormalities and for this purpose preprocessing of retinal images is vital. In this paper, we present a novel automated approach for preprocessing of colored retinal images. The proposed technique improves the quality of input retinal image by separating the background and noisy area from the overall image. It contains coarse ...

  7. Retinal synaptic regeneration via microfluidic guiding channels

    OpenAIRE

    Ping-Jung Su; Zongbin Liu; Kai Zhang; Xin Han; Yuki Saito; Xiaojun Xia; Kenji Yokoi; Haifa Shen; Lidong Qin

    2015-01-01

    In vitro culture of dissociated retinal neurons is an important model for investigating retinal synaptic regeneration (RSR) and exploring potentials in artificial retina. Here, retinal precursor cells were cultured in a microfluidic chip with multiple arrays of microchannels in order to reconstruct the retinal neuronal synapse. The cultured retinal cells were physically connected through microchannels. Activation of electric signal transduction by the cells through the microchannels was demon...

  8. Do we need a retinal pigment epithelium (or choroid) for the maintenance of retinal apposition?

    OpenAIRE

    Foulds, W S

    1985-01-01

    The relative rarity of retinal detachment following extensive surgical resection of choroid and retinal pigment epithelium for choroidal malignant melanoma is discussed in relation to the factors maintaining retinal apposition under these circumstances.

  9. The mechanics of retinal detachment

    Science.gov (United States)

    Chou, Tom; Siegel, Michael

    2013-03-01

    We present a model of the mechanical and fluid forces associated with exudative retinal detachments where the retinal photoreceptor cells separate typically from the underlying retinal pigment epithelium (RPE). By computing the total fluid volume flow arising from transretinal, vascular, and retinal pigment epithelium (RPE) pump currents, we determine the conditions under which the subretinal fluid pressure exceeds the maximum yield stress holding the retina and RPE together, giving rise to an irreversible, extended retinal delamination. We also investigate localized, blister-like retinal detachments by balancing mechanical tension in the retina with both the retina-RPE adhesion energy and the hydraulic pressure jump across the retina. For detachments induced by traction forces, we find a critical radius beyond which the blister is unstable to growth. Growth of a detached blister can also be driven by inflamed tissue within which e.g., the hydraulic conductivities of the retina or choroid increase, the RPE pumps fail, or the adhesion properties change. We determine the parameter regimes in which the blister either becomes unstable to growth, remains stable and finite-sized, or shrinks, allowing possible healing. We present a model of the mechanical and fluid forces associated with exudative retinal detachments where the retinal photoreceptor cells separate typically from the underlying retinal pigment epithelium (RPE). By computing the total fluid volume flow arising from transretinal, vascular, and retinal pigment epithelium (RPE) pump currents, we determine the conditions under which the subretinal fluid pressure exceeds the maximum yield stress holding the retina and RPE together, giving rise to an irreversible, extended retinal delamination. We also investigate localized, blister-like retinal detachments by balancing mechanical tension in the retina with both the retina-RPE adhesion energy and the hydraulic pressure jump across the retina. For detachments induced by traction forces, we find a critical radius beyond which the blister is unstable to growth. Growth of a detached blister can also be driven by inflamed tissue within which e.g., the hydraulic conductivities of the retina or choroid increase, the RPE pumps fail, or the adhesion properties change. We determine the parameter regimes in which the blister either becomes unstable to growth, remains stable and finite-sized, or shrinks, allowing possible healing. This work supported by the Army Research Office through grant 58386MA

  10. Internal Carotid Artery Ectasia: The Value of Imaging Studies Prior to Biopsy of a Retropharyngeal Mass

    Directory of Open Access Journals (Sweden)

    Kenneth Chan

    2010-11-01

    Full Text Available The presence of retropharyngeal tissue mass often raises the suspicion of malignancy, especially in elderly patients. This prompts urgent biopsy to investigate tissue histology. We discuss a case where this is contraindicated as the retropharyngeal mass was illustrated by CT scanning and confirmed with MRI to be a tortuous coursing internal carotid artery. An awareness of this unusual anatomical variation and a careful interpretation of imaging studies both at the stage of differential diagnosis and pre-operative screening are essential to avoid damage to important structures, causing unnecessary complications.

  11. Automated retinal vessel type classification in color fundus images

    Science.gov (United States)

    Yu, H.; Barriga, S.; Agurto, C.; Nemeth, S.; Bauman, W.; Soliz, P.

    2013-02-01

    Automated retinal vessel type classification is an essential first step toward machine-based quantitative measurement of various vessel topological parameters and identifying vessel abnormalities and alternations in cardiovascular disease risk analysis. This paper presents a new and accurate automatic artery and vein classification method developed for arteriolar-to-venular width ratio (AVR) and artery and vein tortuosity measurements in regions of interest (ROI) of 1.5 and 2.5 optic disc diameters from the disc center, respectively. This method includes illumination normalization, automatic optic disc detection and retinal vessel segmentation, feature extraction, and a partial least squares (PLS) classification. Normalized multi-color information, color variation, and multi-scale morphological features are extracted on each vessel segment. We trained the algorithm on a set of 51 color fundus images using manually marked arteries and veins. We tested the proposed method in a previously unseen test data set consisting of 42 images. We obtained an area under the ROC curve (AUC) of 93.7% in the ROI of AVR measurement and 91.5% of AUC in the ROI of tortuosity measurement. The proposed AV classification method has the potential to assist automatic cardiovascular disease early detection and risk analysis.

  12. The ovarian and uterine arteries in the chinchilla (Chinchilla lanigera)

    Scientific Electronic Library Online (English)

    A, Çevik-Demirkan; V, Özdemir; I, Demirkan.

    Full Text Available The purpose of this study was to describe arteries supplying the ovaries and uterus in the chinchilla. Five healthy adult female chinchillas were used. In order to reveal the arterial network by dissecting under a stereoscopic microscope, latex coloured with red ink was injected through the common c [...] arotid artery. The ovaries of the chinchilla are supplied by the arteriae ovaricae which formed end-to-end anastomoses with the cranial termination of the arteria uterina. Soon after leaving the aorta abdominalis, the arteriae ovaricae extended 2-3 mm caudolaterally, then released 1 branch and extended caudally and bifurcated into 2 further branches. One of these supplied branches to fat tissue. The other branch coursed caudally and anastomosed with the arteria circumflexa ilium profunda and dispersed into fat tissue. The arteria ovarica further subdivided into 2 rami ovaricae. The origins of the uterine arteries were exclusively from the left arteria iliaca externa. The arteria uterina gave a branch to the arteria umbilicalis and consecutive branches which supplied to the ureter, urinary bladder and cranial aspects of the vagina. It also gave rise to 2-3 branches to the cervix and further supplied 10-12 meandering branches to the uterine horns. The arteria uterina gave rise to many tortuous arteries to the uterus and provided 2 further branches to the ovary.

  13. Diagnosis of arterial sequestration using multidetector CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Yu Hong, E-mail: yuhong.2002@hotmail.com [Department of Radiology, Changzheng Hospital, Second Military Medical University, Shanghai, 200003 (China); Li Huimin, E-mail: lihuiminphd@163.com [Department of Radiology, Changzheng Hospital, Second Military Medical University, Shanghai, 200003 (China); Liu Shiyuan, E-mail: cjr.liushiyuan@vip.163.com [Department of Radiology, Changzheng Hospital, Second Military Medical University, Shanghai, 200003 (China); Xiao Xiangsheng, E-mail: cjr.xxsh@vip.163.com [Department of Radiology, Changzheng Hospital, Second Military Medical University, Shanghai, 200003 (China)

    2010-11-15

    Background: Arterial sequestration is a rare congenital disorder. The diagnostic evaluation of this condition using multidetector computerized tomography (MDCT) has not been described previously. The purpose of this study was to describe the characteristic features of this disorder and to assess the use of MDCT in visualizing the characteristic anatomic features. Methods: We retrospectively reviewed the records of seven patients with anomalous systemic blood supply to left lower lobe of the lung. All the patients had undergone MDCT angiography. To evaluate the lung parenchyma, bronchial branching pattern, and vascular anatomy, four series of images were systematically reconstructed as follows: contiguous transverse CT scans viewed at mediastinal and pulmonary window settings, oblique coronal and sagittal maximum intensity projections (MIP), multiplanar reconstruction (MPR), and three-dimensional volume-rendered images (VR) of airway and thoracic vascular structures. Results: All 7 cases had isolated and tortuous arterial anatomy from the descending thoracic aorta to the basal segment of the left lower lobe; however, variable distribution of branches was observed. Characteristic findings of anomalous systemic arterial (ASA) supply were distinct from those seen in other pulmonary sequestration syndromes and were well visualized by the use of noninvasive MDCT. Conclusion: Complex CT findings allow clear imaging of arterial sequestration and the ASA blood supply; MDCT angiography has demonstrated its value and accuracy in diagnosing this condition, obviating the use of digital subtraction angiography and magnetic resonance angiography for the diagnosis of arterial sequestration.

  14. The ovarian and uterine arteries in the chinchilla (Chinchilla lanigera

    Directory of Open Access Journals (Sweden)

    A. Cevik-Demirkana

    2010-05-01

    Full Text Available The purpose of this study was to describe arteries supplying the ovaries and uterus in the chinchilla. Five healthy adult female chinchillas were used. In order to reveal the arterial network by dissecting under a stereoscopic microscope, latex coloured with red ink was injected through the common carotid artery. The ovaries of the chinchilla are supplied by the arteriae ovaricae which formed end-to-end anastomoses with the cranial termination of the arteria uterina. Soon after leaving the aorta abdominalis, the arteriae ovaricae extended 2-3mm caudolaterally, then released 1 branch and extended caudally and bifurcated into 2 further branches. One of these supplied branches to fat tissue. The other branch coursed caudally and anastomosed with the arteria circumflexa ilium profunda and dispersed into fat tissue. The arteria ovarica further subdivided into 2 rami ovaricae. The origins of the uterine arteries were exclusively from the left arteria iliaca externa. The arteria uterina gave a branch to the arteria umbilicalis and consecutive branches which supplied to the ureter, urinary bladder and cranial aspects of the vagina. It also gave rise to 2-3 branches to the cervix and further supplied 10-12 meandering branches to the uterine horns. The arteria uterina gave rise to many tortuous arteries to the uterus and provided 2 further branches to the ovary.

  15. 3-D segmentation of retinal blood vessels in spectral-domain OCT volumes of the optic nerve head

    Science.gov (United States)

    Lee, Kyungmoo; Abràmoff, Michael D.; Niemeijer, Meindert; Garvin, Mona K.; Sonka, Milan

    2010-03-01

    Segmentation of retinal blood vessels can provide important information for detecting and tracking retinal vascular diseases including diabetic retinopathy, arterial hypertension, arteriosclerosis and retinopathy of prematurity (ROP). Many studies on 2-D segmentation of retinal blood vessels from a variety of medical images have been performed. However, 3-D segmentation of retinal blood vessels from spectral-domain optical coherence tomography (OCT) volumes, which is capable of providing geometrically accurate vessel models, to the best of our knowledge, has not been previously studied. The purpose of this study is to develop and evaluate a method that can automatically detect 3-D retinal blood vessels from spectral-domain OCT scans centered on the optic nerve head (ONH). The proposed method utilized a fast multiscale 3-D graph search to segment retinal surfaces as well as a triangular mesh-based 3-D graph search to detect retinal blood vessels. An experiment on 30 ONH-centered OCT scans (15 right eye scans and 15 left eye scans) from 15 subjects was performed, and the mean unsigned error in 3-D of the computer segmentations compared with the independent standard obtained from a retinal specialist was 3.4 +/- 2.5 voxels (0.10 +/- 0.07 mm).

  16. Cytomegalovirus retinitis mimicking intraocular lymphoma

    Directory of Open Access Journals (Sweden)

    Patrick Gooi

    2008-12-01

    Full Text Available Patrick Gooi1, James Farmer2, Bernard Hurley3, Elliott Brodbaker41Department of Ophthalmology, University of Calgary, Calgary, Alberta, Canada; 2Department of Pathology and Lab Medicine University of Ottawa and The Ottawa Hospital, Ottawa, Ontario, Canada; 3Department of Ophthalmology, University of Ottawa Eye Institute and The Ottawa Hospital, Ottawa, Ontario, Canada; 4Faculty of Medicine, University of Ottawa, Ottawa, Ontario, CanadaAbstract: We present a case of an unusual retinal infiltrate requiring retinal biopsy for definitive diagnosis. A 62-year-old man with treated lymphoma presented with decreased vision in the right eye associated with a white retinal lesion, which extended inferonasally from an edematous disc. Intraocular lymphoma was considered as a diagnosis; thus, the patient was managed with vitrectomy and retinal biopsy. Cytological analysis of the vitreous aspirate could not rule out a lymphoproliferative disorder. The microbial analysis was negative. Histology of the lesion showed extensive necrosis and large cells with prominent nucleoli. To rule out lymphoma, a battery of immunostains was performed and all were negative. However the limited amount of tissue was exhausted in the process. Subsequently, a hematoxylin and eosin (H/E slide was destained, on which a CMV immunostain was performed. This revealed positivity in the nuclei and intranuclear inclusions within the large atypical cells. A diagnosis of CMV retinitis was made. Retinal biopsy may provide a definitive diagnosis and direct patient care toward intravenous gancyclovir in the case of CMV or toward radiation and chemotherapy for intraocular lymphoma. When faced with a limited amount of tissue, destaining regular H/E slides is a possible avenue to performing additional immunohistochemical studies.Keywords: CMV retinitis, retinal biopsy, immunohistochemistry, destaining

  17. Adenocarcinoma of retinal pigment epithelium.

    OpenAIRE

    Ramahefasolo, S; Soubrane, G.; Dhermy, P; Godel, V; Regenbogen, L; Coscas, G

    1987-01-01

    This report describes a 41-year-old man with an intraocular tumour misinterpreted clinically as choroidal melanoma. The fluorescein angiographic features were not fully characteristic of uveal malignancy, and indeed histopathology revealed the diagnosis of adenocarcinoma of the retinal pigment epithelium. It is suggested that, in cases with the fundus and angiographic findings described here, the rare possibility of adenocarcinoma of retinal pigment epithelium should be kept in mind. Of parti...

  18. A Novel Retinal Identification System

    OpenAIRE

    Mohammad-Shahram Moin; Hamid Abrishami-Moghaddam; Hadi Farzin

    2008-01-01

    This paper presents a novel biometric identification system with high performance based on the features obtained from human retinal images. This system is composed of three principal modules including blood vessel segmentation, feature generation, and feature matching. Blood vessel segmentation module has the role of extracting blood vessels pattern from retinal images. Feature generation module includes the following stages. First, the optical disk is found and a circular region of interest ...

  19. Light and inherited retinal degeneration

    OpenAIRE

    Paskowitz, D M; LaVail, M M; Duncan, J L

    2006-01-01

    Light deprivation has long been considered a potential treatment for patients with inherited retinal degenerative diseases, but no therapeutic benefit has been demonstrated to date. In the few clinical studies that have addressed this issue, the underlying mutations were unknown. Our rapidly expanding knowledge of the genes and mechanisms involved in retinal degeneration have made it possible to reconsider the potential value of light restriction in specific genetic contexts. This review summ...

  20. Retinal imaging and image analysis

    OpenAIRE

    Abramoff, M.D.; Garvin, Mona K.; Sonka, Milan

    2010-01-01

    Many important eye diseases as well as systemic diseases manifest themselves in the retina. While a number of other anatomical structures contribute to the process of vision, this review focuses on retinal imaging and image analysis. Following a brief overview of the most prevalent causes of blindness in the industrialized world that includes age-related macular degeneration, diabetic retinopathy, and glaucoma, the review is devoted to retinal imaging and image analysis methods and their clin...

  1. General pathophysiology in retinal degeneration.

    Science.gov (United States)

    Wert, Katherine J; Lin, Jonathan H; Tsang, Stephen H

    2014-01-01

    Retinal degeneration, including that seen in age-related macular degeneration and retinitis pigmentosa (RP), is the most common form of neural degenerative disease in the world. There is great genetic and allelic heterogeneity of the various retinal dystrophies. Classifications of these diseases can be ambiguous, as there are similar clinical presentations in retinal degenerations arising from different genetic mechanisms. As would be expected, alterations in the activity of the phototransduction cascade, such as changes affecting the renewal and shedding of the photoreceptor OS, visual transduction, and/or retinol metabolism have a great impact on the health of the retina. Mutations within any of the molecules responsible for these visual processes cause several types of retinal and retinal pigment epithelium degenerative diseases. Apoptosis has been implicated in the rod cell loss seen in a mouse model of RP, but the precise mechanisms that connect the activation of these pathways to the loss of phosphodiesterase (PDE6β) function has yet to be defined. Additionally, the activation of apoptosis by CCAAT/-enhancer-binding protein homologous protein (CHOP), after activation of the unfolded protein response pathway, may be responsible for cell death, although the mechanism remains unknown. However, the mechanisms of cell death after loss of function of PDE6, which is a commonly studied mammalian model in research, may be generalizable to loss of function of different key proteins involved in the phototransduction cascade. PMID:24732759

  2. Filling in the retinal image

    Science.gov (United States)

    Larimer, James; Piantanida, Thomas

    1990-01-01

    The optics of the eye form an image on a surface at the back of the eyeball called the retina. The retina contains the photoreceptors that sample the image and convert it into a neural signal. The spacing of the photoreceptors in the retina is not uniform and varies with retinal locus. The central retinal field, called the macula, is densely packed with photoreceptors. The packing density falls off rapidly as a function of retinal eccentricity with respect to the macular region and there are regions in which there are no photoreceptors at all. The retinal regions without photoreceptors are called blind spots or scotomas. The neural transformations which convert retinal image signals into percepts fills in the gaps and regularizes the inhomogeneities of the retinal photoreceptor sampling mosaic. The filling-in mechamism plays an important role in understanding visual performance. The filling-in mechanism is not well understood. A systematic collaborative research program at the Ames Research Center and SRI in Menlo Park, California, was designed to explore this mechanism. It was shown that the perceived fields which are in fact different from the image on the retina due to filling-in, control some aspects of performance and not others. Researchers have linked these mechanisms to putative mechanisms of color coding and color constancy.

  3. Transcranial direct middle meningeal artery puncture for the onyx embolization of dural arteriovenous fistula involving the superior sagittal sinus.

    Science.gov (United States)

    Oh, Jae-Sang; Yoon, Seok-Mann; Shim, Jai-Joon; Bae, Hack-Gun

    2015-01-01

    A 66-year-old woman presented with intermittent paraparesis and generalized tonic-clonic seizure. Cerebral angiography demonstrated dural arteriovenous fistula (AVF) involving superior sagittal sinus (SSS), which was associated with SSS occlusion on the posterior one third. The dural AVF was fed by bilateral middle meningeal arteries (MMAs), superficial temporal arteries (STAs) and occipital arteries with marked retrograde cortical venous reflux. Transfemoral arterial Onyx embolization was performed through right MMA and STA, but it was not successful, which resulted in partial obliteration of dural AVF because of tortuous MMA preventing the microcatheter from reaching the fistula closely enough. Second procedure was performed through left MMA accessed by direct MMA puncture following small decortications of cranium overlying the MMA using diamond drill one week later. Microcatheter could be located far distally to the fistula through 5 F sheath placed into the MMA and complete obliteration of dural AVF was achieved using 3.9 cc of Onyx. PMID:25674345

  4. Changes in cardiopulmonary values after heartworm removal from pulmonary artery using flexible alligator forceps

    International Nuclear Information System (INIS)

    Radiograph, arteriograph, echocardiogram, electrocardiogram and cardiopulmonary values were obtained in dogs with dirofilariasis before and after heartworm removal with a flexible alligator forceps. After heartworm removal, the following results were obtained: 1) Dilations of the pulmonary artery, the right ventricle and the right atrium reduced on radiograph and ultrasonic echocardiogram; 2) tortuousness of the pulmonary artery was reduced, and pruning of the peripheral arteries improved on arteriogram: 3) electrocardiographic findings indicated the correction of right axis deviation in mean electric axis in frontal plane and decreases of voltages; 4) pulmonary arterial and right ventricular pressures fell (improvement of pulmonary hypertension); 5) right cardiac output decreased; 6) heart rate tended to decrease; and 7) total pulmonary arterial resistance decreased. These results indicated that pulmonary arterial resistance and blood flow volume might be reduced, thus decreasing the burden on the heart. It was considered that not only lesions of the pulmonary arteries but also heartworms themselves in the pulmonary artery play an important role in affecting right heart hemodynamics

  5. Retinal detachment in paediatric patients

    International Nuclear Information System (INIS)

    Objective: To assess the causes of retinal detachment in children and the various operative procedures requiring vitreoretinal surgical intervention for the same. Study Design: Case series. Place and Duration of Study: Department of Ophthalmology, Al-Shifa Trust Eye Hospital, Rawalpindi, from January 2006 to May 2009. Methodology: A total of 281 eyes of 258 patients, (aged 0 - 18 years) who underwent vitreo-retinal surgical intervention for retinal detachment were included. Surgical log was searched for the type of retinal detachment and its causes. Frequencies of various interventions done in these patients viz. vitrectomy, scleral buckle, use of tamponading agents, laser photocoagulation and cryotherapy were noted. Results were described as descriptive statistics. Results: Myopia was the cause in 62 (22.1%) and trauma in 51 (18.1%) of the eyes. Total retinal detachment (RD) was treated in 94 (33.5%) eyes, sub total RD in 36 (12.8%), recurrent RD in 32 (11.4%), giant retinal tear in 28 (10%), tractional RD in 15 (5.3%) and exudative RD in 2 (0.7%). Prophylactic laser or cryotherapy was applied in 74 (26.3%) of the eyes. Pars plana vitrectomy (PPV) was carried out in 159 (56.6%) eyes while scleral buckle procedure was done in 129 (45.9%) eyes. Silicon oil was used in 149 (53%), perfluorocarbon liquid in 32 (11.4%) and gas tamponade in 20 (7.1%) eyes. Conclusion: The most common cause of retinal detachment in paediatric patients was myopia, followed by trauma. Total RD was more common as compared to the other types. The most common procedure adopted was pars plana vitrectomy followed by scleral buckle procedure. (author)

  6. Retinal Vein Occlusion.

    Science.gov (United States)

    Sawada, Osamu; Ohji, Masahito

    2016-01-01

    The primary treatment against macular edema with retinal vein occlusion (RVO) has changed from observation in central RVO (CRVO) and laser photocoagulation in branch RVO (BRVO) to administration of intravitreal agents based on anti-vascular endothelial growth factor (VEGF) or anti-inflammatory strategies. Anti-VEGF treatment such as ranibizumab, bevacizumab, or aflibercept improved vision by 13.9-16.2 letters (best-corrected visual acuity) after 12 months versus baseline in patients with macular edema secondary to CRVO. A long-term study showed that reduced follow-up and fewer retreatments resulted in worsening visual acuity. Intravitreal therapy with anti-inflammatory agents stabilized visual acuity in CRVO. However, increased intraocular pressure and cataract progression were frequently observed. Anti-VEGF agents such as ranibizumab or bevacizumab improved visual acuity by 15.5-18.3 letters in patients with macular edema secondary to BRVO after 12 months. The improved vision remained during the long-term follow-up. There was no significant difference between standard care and intravitreal triamcinolone groups in BRVO, and increased intraocular pressure and cataract progression occurred frequently in the triamcinolone group. Anti-VEGF intravitreal administration resulted in good vision in CRVO and BRVO patients and is employed as a primary therapy. Anti-VEGF therapy requires frequent observations and intravitreal injections to maintain good vision. PMID:26501219

  7. Retinal Pericytes Inhibit Activated T Cell Proliferation

    OpenAIRE

    Tu, Zhidan; Li, Yan; Smith, Dawn S.; Sheibani, Nader; Huang, Suber; Kern, Timothy; LIN Feng

    2011-01-01

    The role of retinal pericytes in diabetic retinopathy was not clear. This study demonstrated a novel role of retinal pericytes, suggesting that their immunoregulatory activity could contribute to the pathogenesis of diabetic retinopathy.

  8. Wavelength dependence of the apparent diameter of retinal blood vessels

    Science.gov (United States)

    Park, Robert; Twietmeyer, Karen; Chipman, Russell; Beaudry, Neil; Salyer, David

    2005-04-01

    Imaging of retinal blood vessels may assist in the diagnosis and monitoring of diseases such as glaucoma, diabetic retinopathy, and hypertension. However, close examination reveals that the contrast and apparent diameter of vessels are dependent on the wavelength of the illuminating light. In this study multispectral images of large arteries and veins within enucleated swine eyes are obtained with a modified fundus camera by use of intravitreal illumination. The diameters of selected vessels are measured as a function of wavelength by cross-sectional analysis. A fixed scale with spectrally independent dimension is placed above the retina to isolate the chromatic effects of the imaging system and eye. Significant apparent differences between arterial and venous diameters are found, with larger diameters observed at shorter wavelengths. These differences are due primarily to spectral absorption in the cylindrical blood column.

  9. Retinal Migraine: A Case Report

    Directory of Open Access Journals (Sweden)

    Ayhan Sar?ta?

    2013-03-01

    Full Text Available Retinal migraine is a subgroup of migraine. Retinal migraines are transient monocular visual disturbances that can occur simultaneously with migraine headaches or in a patient with a prior history of migraines. Retinal migraines occur because of hypoperfusion of either the eye or the optic nerve. A 28-year woman was admitted to the emergency department with decreased vision in the right eye and headache. Neurologic and other systemic examinations were normal. Ophthalmologist consultation was performed. Her best corrected visual acuity was 20/20 and the intraocular pressures in both eyes were within normal limits. Color vision testing, fundus examination, and extra ocular muscle function were normal bilaterally. Visual field to confrontation suggested a left temporal hemianopia. Left temporal hemianopia was confirmed by the automatic perimetry test. The diagnosis was retinal migraine in the light of the anamnesis and physical exam findings. Headache and visual complaints had resolved during the follow up in the emergency department. The patient was discharged on the 2nd day of admission with full recovery. As a result, for patients presenting with complaints of headache and visual disturbances, emergency physicians should be alert in terms of retinal migraine, and patients should be considered comprehensively for this reason.

  10. Drusenoid retinal pigment epithelium detachments

    Directory of Open Access Journals (Sweden)

    Miguel Hage Amaro

    2015-10-01

    Full Text Available ABSTRACT The authors make a review of drusenoid retinal pigment epithelium detachments(DPDs, a form of retinal pigment epithelium detachment(PED that evolves from confluent and large soft drusen.Drusenoidretinal pigment epithelial detachments are a recognized element of the "dry" AMD. Until now, no treatment is indicated in drusenoid PEDs. The authors describe the clinical characteristics of drusenoid retinal pigment epithelium detachments (DPEDs and make a review of the DPEDs related in the international literature. We related in this revision paper the multimodal advanced image exams in two cases of dusenoid retinal pigment epithelium detachments (DPEDs and the general characteristics of thisfinding associated with Dry Macular degeneration.Upon examination of the ocular fundusDPEDs emerge as well-circumscribed yellow or yellow–white elevations of the RPE that are usually found within the macula.They may show scalloped borders and a slightly irregular surface. When visualized using fluorescein angiography (FA,DPEDs are typically described as faint hyper-fluorescent in the early phase followed by a slow increase in fluorescence throughout the transit stage of the study without late leakage. With optical coherence tomography (OCT, drusenoid PEDs usually show a smooth contour of the detached hyperreflective RPE band that may have an undulating appearance.Drusenoid PEDs encompass far above the ground possibility type of "dry" AMD that develops in relationship with large confluent soft drusen.At this point no treatment is utilized in drusenoid retinal pigment epithelium detachment(DPEDs.

  11. Reading visual Braille with a retinal prosthesis

    OpenAIRE

    ThomasZaccarinLauritzen; JordanHarris; JoseSahel

    2012-01-01

    Retinal prostheses, which restore partial vision to patients blinded by outer retinal degeneration, are currently in clinical trial. The Argus II retinal prosthesis system was recently awarded CE approval for commercial use in Europe. While retinal prosthesis users have achieved remarkable visual improvement to the point of reading letters and short sentences, the reading process is still fairly cumbersome. This study investigates the possibility of using an epiretinal prosthesis to stimulate...

  12. Shifting subretinal fluid in rhegmatogenous retinal detachment.

    OpenAIRE

    Kirkby, G R; Chignell, A H

    1985-01-01

    In a consecutive series of 470 cases of rhegmatogenous retinal detachment 25 (5%) were found to have shifting subretinal fluid (SRF) at the preoperative examination. The study showed that the association between SRF and rhegmatogenous retinal detachment is unusual but not rare. Shifting SRF was most often associated with aphakic and longstanding retinal detachment, and found in cases in which the retinal holes were small.

  13. Retinal imaging using adaptive optics technology?

    OpenAIRE

    Kozak, Igor

    2014-01-01

    Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effect of wave front distortions. Retinal imaging using AO aims to compensate for higher order aberrations originating from the cornea and the lens by using deformable mirror. The main application of AO retinal imaging has been to assess photoreceptor cell density, spacing, and mosaic regularity in normal and diseased eyes. Apart from photoreceptors, the retinal pigment epithelium, retinal ...

  14. Cell based therapies in retinal diseases

    OpenAIRE

    Touka Banaee

    2014-01-01

    Background Degenerative retinal diseases, including age related macular degeneration, glaucoma, and hereditary retinal dystrophies are major causes of blindness. The principal defect in these diseases is cell loss which is amenable to both cell based neuroprotective and neuroregenerative therapies. To briefly review the lines of research and potential candidates for cell based therapies among retinal diseases.Methods: Review of current literature on stem cell therapies in retinal diseas...

  15. Retinal blood vessels extraction using probabilistic modelling

    OpenAIRE

    Kaba, D; C. Wang; Li, Y; Salazar-Gonzalez, A; Liu, X; Serag, A

    2014-01-01

    The analysis of retinal blood vessels plays an important role in detecting and treating retinal diseases. In this review, we present an automated method to segment blood vessels of fundus retinal image. The proposed method could be used to support a non-intrusive diagnosis in modern ophthalmology for early detection of retinal diseases, treatment evaluation or clinical study. This study combines the bias correction and an adaptive histogram equalisation to enhance the appearance of the blood ...

  16. Instrument for the measurement of retinal vessel oxygen saturation

    Science.gov (United States)

    Drewes, Jonathan J.; Smith, Matthew H.; Denninghoff, Kurt R.; Hillman, Lloyd W.

    1999-06-01

    Retinal vessel oxygen saturation has been suggested as a parameter for monitoring a wide range of conditions including occult blood los and a variety of ophthalmic diseases. We have developed an Eye Oximeter (EOX), that noninvasively measures the oxygen saturation of the blood in individual large retinal vessels using scanning lasers. 1D vessel extinction profiles are obtained at four wavelengths (629, 678, 821 and 899 nm), and the vessel transmittances computed. The oxygen saturation of blood within the vessel is then calculated from the transmittance data. We have performed an in vitro experiment on human blood which demonstrates the calibration of the EOX measurements and validates our oximetry equations. Retinal vessel oxygen saturation was measured in a human subject and found to be 65%O2Sat and 101 - 102%O2Sat in the veins and arteries on the optic disk. Irregularities in the background measured away from the optic disk resulted in a large variance in the calculated saturation when compared to measurements made on the disk.

  17. Identifying All True Vessels from Segmented Retinal Images

    Directory of Open Access Journals (Sweden)

    G. Delucta Mary

    2014-02-01

    Full Text Available Measurements of retinal blood vessel morphology have been shown to be related to the risk of cardiovascular diseases. The wrong identification of vessels may result in a large variation of these measurements, leading to a wrong clinical diagnosis Both the arteries and veins of the retina are generally binary trees, whose properties can be considered either locally or globally. Measurable geometrical changes in diameter, branching angle, length, or tortuosity, as a result of disease, have been described in retinal blood vessels. The detection and measurement of retinal blood vessels can be used to quantify the severity of disease such as hypertension, stroke and arteriosclerosis, as part of the process of automated diagnosis of disease or in the assessment of the progression of therapy. Thus, a reliable method of vessel detection and quantification would be valuable. In this paper, we address the problem of identifying true vessels as a postprocessing step to vascular structure segmentation. We model the segmented vascular structure as a vessel segment graph and formulate the problem of identifying vessels as one of finding the optimal forest in the graph given a set of constraints.

  18. Uterine artery embolization: an effective treatment for intractable obstetric haemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Hong, T.-M.; Tseng, H.-S. E-mail: hstseng@vghtpe.gov.tw; Lee, R.-C.; Wang, J.-H.; Chang, C.-Y

    2004-01-01

    AIM: To present the findings of uterine artery embolization (UAE) in the management of obstetric haemorrhage. MATERIALS AND METHODS: From October 1999 to February 2003, 10 women with postpartum haemorrhage (n=7) and post-abortion haemorrhage with placenta accreta (n=3), were referred to our department for pelvic angiography and possible arterial embolization. RESULTS: Angiography revealed engorged and tortuous uterine arteries in all patients; and contrast medium extravasation in three patients. Eight patients (three with and five without detectable active bleeding) then underwent bilateral UAE. Medium-sized (250-355 {mu}m) polyvinyl alcohol particles were injected via a coaxial catheter into the uterine arteries, followed by gelatin sponge pieces via a 4 F Cobra catheter. Microcoil devascularization was also performed in the two patients with visible, active bleeding. The vaginal bleeding resolved in all patients, without any ischaemic complications. At follow-up, all patients who underwent UAE had normal menstruation; three of them subsequently gave birth to full-term healthy babies. CONCLUSION: Selective UAE by the coaxial method is safe and effective to control obstetric haemorrhage, with the potential to preserve fertility.

  19. Uterine artery embolization: an effective treatment for intractable obstetric haemorrhage

    International Nuclear Information System (INIS)

    AIM: To present the findings of uterine artery embolization (UAE) in the management of obstetric haemorrhage. MATERIALS AND METHODS: From October 1999 to February 2003, 10 women with postpartum haemorrhage (n=7) and post-abortion haemorrhage with placenta accreta (n=3), were referred to our department for pelvic angiography and possible arterial embolization. RESULTS: Angiography revealed engorged and tortuous uterine arteries in all patients; and contrast medium extravasation in three patients. Eight patients (three with and five without detectable active bleeding) then underwent bilateral UAE. Medium-sized (250-355 ?m) polyvinyl alcohol particles were injected via a coaxial catheter into the uterine arteries, followed by gelatin sponge pieces via a 4 F Cobra catheter. Microcoil devascularization was also performed in the two patients with visible, active bleeding. The vaginal bleeding resolved in all patients, without any ischaemic complications. At follow-up, all patients who underwent UAE had normal menstruation; three of them subsequently gave birth to full-term healthy babies. CONCLUSION: Selective UAE by the coaxial method is safe and effective to control obstetric haemorrhage, with the potential to preserve fertility

  20. Surgical techniques for selected giant retinal tears.

    Science.gov (United States)

    Michels, R G; Rice, T A; Blankenship, G

    1983-01-01

    Based on clinical experience, improved methods for treating giant retinal tears with an inverted retinal flap are described. In all cases a broad encircling scleral buckle is used in conjunction with a broad zone of peripheral chorioretinal adhesion produced by cryotherapy and, often, supplemented by postoperative photocoagulation. This virtually eliminates recurrent retinal detachment from an anterior location, if the retinal flap can be properly unfolded and the retina is initially reattached. Vitrectomy is done in all these cases, and an intraocular bubble is used to unfold and reposition the retinal flap during or after surgery. If the retinal flap is especially stiff or foreshortened, special techniques are used to incarcerate the edge of the retinal flap in the pars plana or the peripheral choroid, or transvitreal suturing techniques are used to secure the edge of the retinal flap to the eyewall before fluid-gas exchange is performed. This insures proper unfolding of the flap by the intraocular bubble. Applying retinal cryotherapy before performing the vitrectomy seems to reduce the occurrence of postoperative proliferative vitreoretinopathy (PVR), perhaps because retinal pigment epithelial cells in the vitreous cavity are removed during vitrectomy. Frequent, detailed examination during the first three weeks after surgery and use of postoperative photocoagulation to supplement the cryotherapy seem to prevent recurrent detachment from anterior leakage of subretinal fluid beneath the retinal flap or through other anterior retinal breaks. PMID:6356259

  1. Imaging of retinal and choroidal vascular tumours

    OpenAIRE

    HEIMANN, H.; Jmor, F; DAMATO, B

    2012-01-01

    The most common intraocular vascular tumours are choroidal haemangiomas, vasoproliferative tumours, and retinal haemangioblastomas. Rarer conditions include cavernous retinal angioma and arteriovenous malformations. Options for ablating the tumour include photodynamic therapy, argon laser photocoagulation, trans-scleral diathermy, cryotherapy, anti-angiogenic agents, plaque radiotherapy, and proton beam radiotherapy. Secondary effects are common and include retinal exudates, macular oedema, e...

  2. Human retinal circuitry and physiology

    Directory of Open Access Journals (Sweden)

    Christina Joselevitch

    2008-01-01

    Full Text Available Every second, in an average daytime light environment, hundreds of millions of photons enter the human eye and arrive at the photoreceptor layer of the retina. All our information about the visible world is contained in this rain of photons. The retina is a complex tissue, literally an extension of the brain, which transforms the rain of photons into bioelectric signals containing all the information available to the brain to interpret and respond to the external visual world. A considerable amount of processing takes place within the retinal tissue itself. Understanding what kind of processing takes place at each retinal stage is crucial for understanding normal vision, vision in the presence of diseases affecting the retina, and, ultimately, for the development of therapies to treat such diseases. This manuscript reviews the relation between structure and function of the different retinal pathways and addresses their possible roles for visual perception.

  3. Human retinal circuitry and physiology

    Scientific Electronic Library Online (English)

    Christina, Joselevitch.

    2008-12-01

    Full Text Available Every second, in an average daytime light environment, hundreds of millions of photons enter the human eye and arrive at the photoreceptor layer of the retina. All our information about the visible world is contained in this rain of photons. The retina is a complex tissue, literally an extension of [...] the brain, which transforms the rain of photons into bioelectric signals containing all the information available to the brain to interpret and respond to the external visual world. A considerable amount of processing takes place within the retinal tissue itself. Understanding what kind of processing takes place at each retinal stage is crucial for understanding normal vision, vision in the presence of diseases affecting the retina, and, ultimately, for the development of therapies to treat such diseases. This manuscript reviews the relation between structure and function of the different retinal pathways and addresses their possible roles for visual perception.

  4. Anatomy of the Ophthalmic Artery: A Review concerning Its Modern Surgical and Clinical Applications

    Science.gov (United States)

    Michalinos, Adamantios; Zogana, Sofia; Kotsiomitis, Evangelos; Mazarakis, Antonios; Troupis, Theodore

    2015-01-01

    Anatomy of ophthalmic artery has been thoroughly studied and reviewed in many anatomical and surgical textbooks and papers. Issues of interest are its intracranial and extracranial course, its branches, its importance for vision, and its interaction with various intracranial pathologies. Improvement of our understanding about pathophysiology of certain diseases like aneurysm formation, central retinal artery occlusion, and retinoblastoma and also invention of new therapeutic modalities like superselective catheterization, intra-arterial fibrinolysis, and intra-arterial chemotherapy necessitate a reappraisal of its anatomy from a clinical point of view. The aim of this review is to examine clinical anatomy of ophthalmic artery and correlate it with new diagnostic and therapeutic applications.

  5. Imaging pulse wave propagation in human retinal vessels using full-field swept-source optical coherence tomography.

    Science.gov (United States)

    Spahr, Hendrik; Hillmann, Dierck; Hain, Carola; Pfäffle, Clara; Sudkamp, Helge; Franke, Gesa; Hüttmann, Gereon

    2015-10-15

    We demonstrate a new noninvasive method to assess biomechanical properties of the retinal vascular system. Phase-sensitive full-field swept-source optical coherence tomography (PhS-FF-SS-OCT) is used to investigate retinal vascular dynamics at unprecedented temporal resolution. The motion of retinal tissue that is induced by expansion of the vessels therein is measured with an accuracy of about 10 nm. The pulse shapes of arterial and venous pulsations, their temporal delays, as well as the frequency-dependent pulse propagation through the capillary bed, are determined. For the first time, imaging speed and motion sensitivity are sufficient for a direct measurement of pulse waves propagating with more than 600 mm/s in retinal vessels of a healthy young subject. PMID:26469616

  6. Retinal Optical Coherence Tomography Imaging

    Science.gov (United States)

    Drexler, Wolfgang; Fujimoto, James G.

    The eye is essentially transparent, transmitting light with only minimal optical attenuation and scattering providing easy optical access to the anterior segment as well as the retina. For this reason, ophthalmic and especially retinal imaging has been not only the first but also most successful clinical application for optical coherence tomography (OCT). This chapter focuses on the development of OCT technology for retinal imaging. OCT has significantly improved the potential for early diagnosis, understanding of retinal disease pathogenesis, as well as monitoring disease progression and response to therapy. Development of ultrabroad bandwidth light sources and high-speed detection techniques has enabled significant improvements in ophthalmic OCT imaging performance, demonstrating the potential of three-dimensional, ultrahigh-resolution OCT (UHR OCT) to perform noninvasive optical biopsy of the living human retina, i.e., the in vivo visualization of microstructural, intraretinal morphology in situ approaching the resolution of conventional histopathology. Significant improvements in axial resolution and speed not only enable three-dimensional rendering of retinal volumes but also high-definition, two-dimensional tomograms, topographic thickness maps of all major intraretinal layers, as well as volumetric quantification of pathologic intraretinal changes. These advances in OCT technology have also been successfully applied in several animal models of retinal pathologies. The development of light sources emitting at alternative wavelengths, e.g., around #1,060 nm, not only enabled three-dimensional OCT imaging with enhanced choroidal visualization but also improved OCT performance in cataract patients due to reduced scattering losses in this wavelength region. Adaptive optics using deformable mirror technology, with unique high stroke to correct higher-order ocular aberrations, with specially designed optics to compensate chromatic aberration of the human eye, in combination with three-dimensional UHR OCT, recently enabled in vivo cellular resolution retinal imaging.

  7. Adenocarcinoma of retinal pigment epithelium.

    Science.gov (United States)

    Ramahefasolo, S; Soubrane, G; Dhermy, P; Godel, V; Regenbogen, L; Coscas, G

    1987-01-01

    This report describes a 41-year-old man with an intraocular tumour misinterpreted clinically as choroidal melanoma. The fluorescein angiographic features were not fully characteristic of uveal malignancy, and indeed histopathology revealed the diagnosis of adenocarcinoma of the retinal pigment epithelium. It is suggested that, in cases with the fundus and angiographic findings described here, the rare possibility of adenocarcinoma of retinal pigment epithelium should be kept in mind. Of particular interest were the changing pathological findings in the various parts of the tumour, which paralleled the fluorescein angiographic pattern. Images PMID:3651364

  8. Tortuosity and calcification of the splenic artery. More than an additional finding

    International Nuclear Information System (INIS)

    Tortuosity of the splenic artery and calcification of the vessel wall are typical additional findings on plain abdominal x-ray. The combination of both anomalies is common in elderly persons presenting without symptoms of splenic ischemia. Its pathogenesis is thought to be multifactorial. In infancy and childhood, the splenic artery is stretched in its entire course. A growing difference between the length of the vessel and the distance between its origin and the splenic hilum gives rise to tortuosity. The artery's proximal segment is involved more frequently and more severely than the distal one. The tortuous route of the vessel is accentuated by the direction of its major branches, which is roughly perpendicular to the main trajectory. Neither tortuosity nor calcification should be taken to be risk factors for the comparatively common splenic artery aneurysm. Calcific deposits are not confined to the media but are also detected in the intima of the vascular wall. Critical narrowings of the lumen arising on the calcium deposits are not observed. Calcifying atherosclerosis of the splenic artery is comparable to medial sclerosis of the peripheral arteries frequently noticed in diabetics and dialysis patients. Only the less important calcification of the intima may be attributed to mechanisms of the hydrohemodynamic theory of atherosclerosis. The spleen's blood storage capacity may contribute to the characteristic age-dependent alterations of the shape and course of the splenic artery. (orig.)

  9. MULTIDETECTOR-ROW COMPUTED TOMOGRAPHY PATTERNS OF BRONCHOESPHAGEAL ARTERY HYPERTROPHY AND SYSTEMIC-TO-PULMONARY FISTULA IN DOGS.

    Science.gov (United States)

    Ledda, Gianluca; Caldin, Marco; Mezzalira, Giorgia; Bertolini, Giovanna

    2015-01-01

    Anomalies involving arterial branches in the lungs are one of the causes of hemoptysis in humans and dogs. Congenital and acquired patterns of bronchoesophageal artery hypertrophy have been reported in humans based on CT characteristics. The purpose of this retrospective study was to describe clinical, echocardiographic, and multidetector computed tomography features of bronchoesophageal artery hypertrophy and systemic-to-pulmonary arterial communications in a sample of 14 dogs. Two main vascular patterns were identified in dogs that resembled congenital and acquired conditions reported in humans. Pattern 1 appeared as an aberrant origin of the right bronchoesophageal artery, normal origin of the left one, and enlargement of both the bronchial and esophageal branches that formed a dense network terminating in a pulmonary artery through an orifice. Pattern 2 appeared as a normal origin of both right and left bronchoesophageal arteries, with an enlarged and tortuous course along the bronchi to the periphery of the lung, where they communicated with subsegmental pulmonary arteries. Dogs having Pattern 1 also had paraesophageal and esophageal varices, with the latter being confirmed by videoendoscopy examination. Authors conclude that dogs with Pattern 1 should be differentiated from dogs with other congenital vascular systemic-to-pulmonary connections. Dogs having Pattern 2 should be evaluated for underlying pleural or pulmonary diseases. Bronchoesophageal artery hypertrophy can be accompanied by esophageal venous engorgement and should be included in the differential diagnosis for esophageal and paraesophageal varices in dogs. PMID:25961802

  10. Cirsoid Aneurysm of Coronary Arteries Associated with Arterioventricular Fistula Evaluated by 64-Multidetector CT Coronary Angiography: Depiction of a Case

    International Nuclear Information System (INIS)

    A female patient with severe pulmonary hypertension was admitted for lung transplant evaluation. As an incidental finding, the chest CT showed diffuse and dilated coronaries, not detected at previous echocardiography. A coronary CT angiography was then performed using a 64-multidetector computed tomography (MDCT) scanner to better evaluate the coronary tree. The images obtained after postprocessing demonstrated tremendously aneurysmatic and tortuous coronary arteries and the presence of a septal branch deepening into the myocardium and penetrating the right ventricle cavity, forming an abnormal arterioventricular fistula. A causal relation between the aneurysms and the fistula is suspected.

  11. Fractal Analysis Reveals Reduced Complexity of Retinal Vessels in CADASIL

    Science.gov (United States)

    Cavallari, Michele; Falco, Teresa; Frontali, Marina; Romano, Silvia; Bagnato, Francesca; Orzi, Francesco

    2011-01-01

    The Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) affects mainly small cerebral arteries and leads to disability and dementia. The relationship between clinical expression of the disease and progression of the microvessel pathology is, however, uncertain as we lack tools for imaging brain vessels in vivo. Ophthalmoscopy is regarded as a window into the cerebral microcirculation. In this study we carried out an ophthalmoscopic examination in subjects with CADASIL. Specifically, we performed fractal analysis of digital retinal photographs. Data are expressed as mean fractal dimension (mean-D), a parameter that reflects complexity of the retinal vessel branching. Ten subjects with genetically confirmed diagnosis of CADASIL and 10 sex and age-matched control subjects were enrolled. Fractal analysis of retinal digital images was performed by means of a computer-based program, and the data expressed as mean-D. Brain MRI lesion volume in FLAIR and T1-weighted images was assessed using MIPAV software. Paired t-test was used to disclose differences in mean-D between CADASIL and control groups. Spearman rank analysis was performed to evaluate potential associations between mean-D values and both disease duration and disease severity, the latter expressed as brain MRI lesion volumes, in the subjects with CADASIL. The results showed that mean-D value of patients (1.42±0.05; mean±SD) was lower than control (1.50±0.04; p?=?0.002). Mean-D did not correlate with disease duration nor with MRI lesion volumes of the subjects with CADASIL. The findings suggest that fractal analysis is a sensitive tool to assess changes of retinal vessel branching, likely reflecting early brain microvessel alterations, in CADASIL patients. PMID:21556373

  12. Arterial embolism

    Science.gov (United States)

    ... the affected artery Shedding (sloughing) of skin Skin erosion ( ulcer ) Tissue death (necrosis; skin is dark and ... of the following tests: Euglobulin lysis time (ELT) Factor VIII assay Isotope study of the affected organ ...

  13. [Arterial heterogeneity].

    Science.gov (United States)

    Gouëffic, Y; Davaine, J-M; Merlini, T; Rimbert, A; Hérisson, F; Heymann, M-F; Heymann, D; Steenman, M; Lambert, G

    2013-01-01

    More and more clinical observations and trials support the concept of heterogeneity of atheroma according to the arterial bed. In a pilot study named "Étude Comparative des Lésions Athéromateuses" (ECLA), we have shown that carotid and femoral plaques possess different characteristics. Carotid arteries display increased lipid content compared to femoral arteries whereas femoral arteries are more prone to calcify and to develop osteoid metaplasia. These observations should lead the researcher and the clinician to look at the cellular and molecular mechanisms governing the heterogeneity of atheromas. At last, a better understanding of the characteristics of plaques should help us to determine plaque stability, to prevent cardiovascular events and to choose the best medical, endovascular or surgical option. PMID:23159822

  14. Mining retinal connectomes

    Directory of Open Access Journals (Sweden)

    Robert Marc

    2010-06-01

    Full Text Available Robert E. Marc and James R. Anderson, John A. Moran Eye Center, University of Utah Automated transmission electron microscope (TEM allows extensive capture of contiguous 2D and 3D imagery, posing challenges for data storage, access, viewing, annotation, tracking and analysis. Such datasets quickly transcend a userʼs capacity for analysis. And, as annotated anatomical data sets represent significant investment of resources, we argue they should follow Open Data concepts for access and reuse. The Viking application (Anderson et al., 2010, J Microscopy was our solution to view and annotate RC1, a 16.5 TB ultrastructural retinal connectome volume. Viking is HTTP-compliant, supports concurrent authenticated users, and collaborative annotation strategies, including mining, graphing and rendering neural networks. It demarcates viewing and analysis from capture and hosting and permits applying image transforms in real-time. It also permits the fusion of registered thin-section optical molecular data with TEM image data, augmenting the collection of cell classification metadata. Connectome dataset RC1 was imaged at 2 nm resolution, balancing competing constraints of large-area sampling and fine-scale cell association maps (subclasses of chemical synapses, gap junctions, adherens junctions, organelle patterning. We use a crowd-sourcing strategy for annotation with Viking. This leads to rapid assembly of directed cyclic network graphs, dynamically visualized via a web-services Viz application that also provides network validation, error discovery and correction. The network graph below illustrates the associations of a single class A-II glycinergic amacrine cell (C467, circled in the rabbit retina tracked through four synaptic “hops”. Even if automated tracking and annotation were viable, a Viz-like application would still be critical for finding and correcting network errors. Moreover, crowd-sourcing enables the discovery of novelty (connective, associative and ultrastructural, which automated tools have yet to achieve. In a year of analysis, mining connectome RC1 has uncovered new synaptic pathways and topologies, new non-neural activities, and new signaling states. Intensive mining of connectomics datasets provides the unique opportunity to build realistic system models based on complete synaptic partner maps. Support: NEI EY02576, NEI EY015128, P30EY014800, NIH T32DC008553, NSF 0941717, Research to Prevent Blindness. Disclosure: REM is a principal of Signature Immunologics, Inc.

  15. [Doppler ultrasonographic velocimetry of the central retinal artery and central retinal vein].

    Science.gov (United States)

    Mális, V; Kovácik, A; Cuvala, J

    1994-10-01

    A blood flow rate in the arteria and vena centralis retinae was measured by Doppler-ultrasonographic method in a group of 36 patients of an average age of 59.35 years. The patients did not suffer any cardiovascular disease, glaucoma, diabetes mellitus-factors which influence the blood viscosity. In the arteria centralis retinae, there was measured a maximum systolic rate of 10.25 +/- 2.66 cm/s and a end diastolic rate of 5.24 +/- 1.27 cm/s. In the vena centralis retinae, there was measured an average maximum flow rate of 5.89 +/- 1.72 cm/s and end diastolic rate of 4.1 +/- 1.28 cm/s (minimum 2.12; maximum 6.2 cm/s). A procedure of examination and terms of its optimalisation are described there. PMID:7805121

  16. Retinal vessel diameters in relation to hematocrit variation during acclimatization of highlanders to sea level altitude

    DEFF Research Database (Denmark)

    Kofoed, Peter Kristian; Sander, Birgit

    2009-01-01

    PURPOSE: To examine variations in retinal vessel diameters during acclimatization of native highlanders to normobaric normoxia at sea level. METHODS: Fifteen healthy residents of the greater La Paz region in Bolivia (3600 m above sea level) were examined thrice over a 72-day period, after having traveled by airplane to Copenhagen, Denmark, near sea level. RESULTS: In the study subjects, hematocrit decreased from 49.6% (day 2) to 45.9% (P = 0.0066, day 23) and 41.7% (P <0.0001, day 72); from days 2 to 23, retinal vein diameter increased by 2.68% (P = 0.0079); whereas retinal artery and vein diameters were indistinguishable from baseline after 72 days. No funduscopic signs of retinopathy were observed. Arterial blood pressure remained stable throughout the study. CONCLUSIONS: Although a 16% reduction in hematocrit occurred between days 2 and 72 after arrival at sea level, the only significant excursion observed was that the diameter of the veins was larger at day 23 than at days 2 and 72. Retinal vessel diameters demonstrated a wide homeostatic range during acclimatization-driven hematocrit variation.

  17. Retinal detachment in congenital glaucoma.

    OpenAIRE

    Cooling, R. J.; Rice, N S; McLeod, D.

    1980-01-01

    This paper reports the occurrence of retinal detachment in 18 patients suffering from congenital glaucoma. Difficulty in establishing control of the glaucoma and the presence of high myopia were common findings. The poor results of detachment surgery were related to opacites in the media preventing evaluation of the renal details and the development of massive preretinal retraction.

  18. Retinitis Pigmentosa and Education Issues

    Science.gov (United States)

    Brown, Thomas J.

    2005-01-01

    Retinitis Pigmentosa includes a number of inherited diseases which usually result in blindness. The disease is progressive in nature and begins with the deterioration of cells in the eye responsible for peripheral vision. As the condition worsens there is a gradual loss of peripheral vision and night blindness. Proper educational planning requires…

  19. Prophylactic treatment of retinal breaks

    DEFF Research Database (Denmark)

    Blindbæk, Søren Leer; Grauslund, Jakob

    2015-01-01

    -lamp biomicroscopy or Goldmann 3-mirror examination - with regard to retinal breaks as well as the indication of prophylactic treatment in asymptomatic and symptomatic breaks. A total of 2941 publications were identified with PubMed and Medline searches. Two manual search strategies were used for papers in English...

  20. Clinical application of uterine arterial embolization for treatment of placenta praevia with hemorrhage in advanced stage of pregnancy

    International Nuclear Information System (INIS)

    Objective: To investigate the value of the uterine arterial embolization for the placenta praevia and hemorrhage in late stage of pregnancy. Methods: 16 patients of placenta praevia with hemorrhage in late stage of pregnancy were treated with uterine arterial embolization (UAE)and simultaneously with Lee Rivanol intra-amniotic membrane injection for artificial laboring. Results: During late stage of pregnancy, uterine arteries appeared to be elongated and enlarged with numerous dilated tortuous branches with positive proportion to gestalional age, and rich in blood supply of the placenta. 15 cases passed successfully through the induced abortion. The procedure completed with an average of 4.5 h afterwards, without postpartum hemorrhage. The other ease failed due to complicated reasons and cured by caesarean section. Conclusion: UAE is a safe and effective method for late stage placenta praevia with hemaorrhage and also provides the reservation of fertility and together with promotion of induced abortion. (authors)

  1. Retinal nerve fiber layer thickness map and blood flow pulsation measured with SDOCT

    Science.gov (United States)

    Mujat, Mircea; Chan, Raymond C.; Cense, Barry; Pierce, Mark; Park, Hyle; Joo, Chulmin; Chen, Teresa C.; de Boer, Johannes F.

    2006-02-01

    Spectral-Domain Optical Coherence Tomography (SDOCT) allows for in-vivo video-rate investigation of biomedical tissue depth structure intended for non-invasive optical diagnostics. It has been suggested that OCT can be used for di-agnosis of glaucoma by measuring the thickness of the Retinal Nerve Fiber Layer (RNLF). We present an automated method for determining the RNFL thickness from a 3-D dataset based on edge detection using a deformable spline algo-rithm. The RNFL thickness map is combined with an integrated reflectance map and retinal cross-sectional images to provide the ophthalmologist with a familiar image for interpreting the OCT data. The video-rate capabilities of our SDOCT system allow for mapping the true retinal topography since motion artifacts are significantly reduced as com-pared to slower time-domain systems. Combined with Doppler Velocimetry, SDOCT also provides information on retinal blood flow dynamics. We analyzed the pulsatile nature of the bidirectional flow dynamics in an artery-vein pair for a healthy volunteer at different locations and for different blood vessel diameters. The Doppler phase shift is determined as the phase difference at the same point of adjacent depth profiles, and is integrated over the area delimited by two circles corresponding to the blood vessels location. Its temporal evolution clearly shows the blood flow pulsatile nature, the cardiac cycle, in both artery and vein. The artery is identified as having a stronger variation of the integrated phase shift. We observe that artery pulsation is always easily detectable, while vein pulsation seems to depend on the veins diameter.

  2. Prostatic Artery Embolization for Enlarged Prostates Due to Benign Prostatic Hyperplasia. How I Do It

    International Nuclear Information System (INIS)

    Prostatic artery embolization (PAE) has emerged as an alternative to surgical treatments for benign prostatic hyperplasia (BPH). Patient selection and refined technique are essential for good results. Urodynamic evaluation and magnetic resonance imaging are very important and technical limitations are related to elderly patients with tortuous and atherosclerotic vessels, anatomical variations, difficulty visualizing and catheterizing small diameter arteries feeding the prostate, and the potential risk of bladder and rectum ischemia. The use of small-diameter hydrophilic microcatheters is mandatory. Patients can be treated safely by PAE with low rates of side effects, reducing prostate volume with clinical symptoms and quality of life improvement without urinary incontinence, ejaculatory disorders, or erectile dysfunction. A multidisciplinary approach with urologists and interventional radiologists is essential to achieve better results

  3. Prostatic Artery Embolization for Enlarged Prostates Due to Benign Prostatic Hyperplasia. How I Do It

    Energy Technology Data Exchange (ETDEWEB)

    Carnevale, Francisco C., E-mail: fcarnevale@uol.com.br [University of Sao Paulo Medical School, Interventional Radiology Unit (Brazil); Antunes, Alberto A., E-mail: antunesuro@uol.com.br [University of Sao Paulo Medical School, Division of Urology (Brazil)

    2013-12-15

    Prostatic artery embolization (PAE) has emerged as an alternative to surgical treatments for benign prostatic hyperplasia (BPH). Patient selection and refined technique are essential for good results. Urodynamic evaluation and magnetic resonance imaging are very important and technical limitations are related to elderly patients with tortuous and atherosclerotic vessels, anatomical variations, difficulty visualizing and catheterizing small diameter arteries feeding the prostate, and the potential risk of bladder and rectum ischemia. The use of small-diameter hydrophilic microcatheters is mandatory. Patients can be treated safely by PAE with low rates of side effects, reducing prostate volume with clinical symptoms and quality of life improvement without urinary incontinence, ejaculatory disorders, or erectile dysfunction. A multidisciplinary approach with urologists and interventional radiologists is essential to achieve better results.

  4. Argus II Retinal Prosthesis System for peripheral retinal degeneration

    Directory of Open Access Journals (Sweden)

    Maura Arsiero

    2014-11-01

    Full Text Available There is currently no treatment for retinitis pigmentosa, retinal degenerations or for severe sight impairments, though sometimes attempts are made to slow down the degeneration process through the use of dark glasses and vitamin A and E supplements. To manage light sensitivity, the use of yellow-orange glasses and lateral protection of the eyes from light is sometimes used. Treatment of complications such as cataracts, macular oedema and inflammation may offer some improvement in quality of life, as may learning Braille, improving social support, the use of guide dogs or a white cane. The Argus(R II Retinal Prosthesis System ("Argus II" is the first commercially available retinal device for this condition, although others are in development. In a healthy eye, the photoreceptors in the retina convert light into electrochemical impulses that are sent through the optic nerve and into the brain, where they are decoded into images. If the photoreceptors no longer function correctly—due to conditions such as retinitis pigmentosa—the first step in this process is disrupted, and the visual system cannot transform light into images. The Argus II bypasses the damaged photoreceptors altogether. A miniature video camera housed in the patient’s glasses captures a scene. The video is sent to a small patient-worn computer (i.e., the video processing unit – VPU where it is processed and transformed into instructions that are sent back to the glasses via a cable. These instructions are transmitted wirelessly to an antenna in the implant. The signals are then sent to the electrode array, which emits small pulses of electricity. These pulses bypass the damaged photoreceptors and stimulate the retina’s remaining cells, which transmit the visual information along the optic nerve to the brain, creating the perception of patterns of light. Patients learn to interpret these visual patterns. The Argus II offers benefits to patients with peripheral retinal degeneration, who currently have no treatment options. The device, safe and effective, provides a way for patients to improve their independence, employment and mobility.

  5. Bilateral retinal cyst accompanying with renal and thyroidal multiorgan cyst

    Directory of Open Access Journals (Sweden)

    Amber ?enel

    2011-01-01

    Full Text Available Although retinal cysts are commonly seen in von Hippel Lindau syndrome, bilateral retinal cysts can occasionally appear unrelated to this syndrome. Retinal cysts can be confused with retinal tumours and infectious diseases of retina. In this report we represent a patient demonstrating bilateral retinal cyst accompanying with renal and thyroidal multiorgan cysts without Von-Hippel Lindau syndrome.

  6. Failed retinal surgery caused by intraocular gas injection.

    OpenAIRE

    Johnston, P. B.; Maguire, C. J.; Logan, W. C.

    1988-01-01

    Four patients developed inferior retinal redetachment following initially successful surgery which included intraocular injection of air and sulphahexafluoride (SF6) mixture. In each case the intravitreal gas bubble produced vitreoretinal traction which opened inferior retinal breaks and led to retinal separation. Cautious use of intraocular gas is advised when bullous upper rhegmatogenous retinal detachments are accompanied by inferior retinal breaks.

  7. Carotid artery surgery

    Science.gov (United States)

    Carotid endarterectomy; CAS surgery; Carotid artery stenosis - surgery; Endarterectomy - carotid artery ... through the catheter around the blocked area during surgery. Your carotid artery is opened. The surgeon removes ...

  8. Retinal vasculature classification using novel multifractal features

    Science.gov (United States)

    Ding, Y.; Ward, W. O. C.; Duan, Jinming; Auer, D. P.; Gowland, Penny; Bai, L.

    2015-11-01

    Retinal blood vessels have been implicated in a large number of diseases including diabetic retinopathy and cardiovascular diseases, which cause damages to retinal blood vessels. The availability of retinal vessel imaging provides an excellent opportunity for monitoring and diagnosis of retinal diseases, and automatic analysis of retinal vessels will help with the processes. However, state of the art vascular analysis methods such as counting the number of branches or measuring the curvature and diameter of individual vessels are unsuitable for the microvasculature. There has been published research using fractal analysis to calculate fractal dimensions of retinal blood vessels, but so far there has been no systematic research extracting discriminant features from retinal vessels for classifications. This paper introduces new methods for feature extraction from multifractal spectra of retinal vessels for classification. Two publicly available retinal vascular image databases are used for the experiments, and the proposed methods have produced accuracies of 85.5% and 77% for classification of healthy and diabetic retinal vasculatures. Experiments show that classification with multiple fractal features produces better rates compared with methods using a single fractal dimension value. In addition to this, experiments also show that classification accuracy can be affected by the accuracy of vessel segmentation algorithms.

  9. Retinal venous oxygen saturation and cardiac output during controlled hemorrhage and resuscitation.

    Science.gov (United States)

    Denninghoff, Kurt R; Smith, Matthew H; Lompado, Art; Hillman, Lloyd W

    2003-03-01

    The objective was to test calibration of an eye oximeter (EOX) in a vitiligo swine eye and correlate retinal venous oxygen saturation (Srv(O(2))), mixed venous oxygen saturation (Sv(O(2))), and cardiac output (CO) during robust changes in blood volume. Ten anesthetized adult Sinclair swine with retinal vitiligo were placed on stepwise decreasing amounts of oxygen. At each oxygen level, femoral artery oxygen saturation (Sa(O(2))) and retinal artery oxygen saturation (Sra(O(2))) were obtained. After equilibration on 100% O(2), subjects were bled at 1.4 ml. kg(-1). min(-1) for 20 min. Subsequently, anticoagulated shed blood was reinfused at the same rate. During graded hypoxia, exsanguination, and reinfusion, Sra(O(2)) and Srv(O(2)) were measured by using the EOX, and CO and Sv(O(2)) were measured by using a pulmonary artery catheter. During graded hypoxia, Sra(O(2)) correlated with Sa(O(2)) (r = 0.92). Srv(O(2)) correlated with Sv(O(2)) (r = 0.89) during exsanguination and reinfusion. Sv(O(2)) and Srv(O(2)) correlated with CO during blood removal and resuscitation (r = 0.92). Use of vitiligo retinas improved the calibration of EOX measurements. In this robust hemorrhage model, Srv(O(2)) correlates with CO and Sv(O(2)) across the range of exsanguination and resuscitation. PMID:12571124

  10. Influence of pan retinal photocoagulation on diabetic retinal and corneal

    Directory of Open Access Journals (Sweden)

    Chen Wang

    2015-08-01

    Full Text Available Diabetic retinopathy(DRis one of the most serious microvascular complications of diabetes. It also is a world's major causes of blind eye diseases. Although the injection of anti-vascular endothelial growth factor intraocular drug is becoming a hotspot of current research. Pan retinal photocoagulation(PRPremains the effective and economical treatment for DR. As a destructive treatment, PRP will inevitably cause some changes on the normal morphology and function of the retinal and cornea. Currently, with the development of the optical coherence tomography, confocal microscopy and other auxiliary examination, we have more accurate and objective research to better understand the laser-neural tissue interaction. This may help us to protect the patient's visual function more efficiently.

  11. [Retinal vein occlusion: Therapy of retinal vein occlusion].

    Science.gov (United States)

    Feltgen, N; Pielen, A

    2015-08-01

    Treatment of retinal vein occlusion can be systemic or local. Therapeutic strategies include improved blood supply, treatment of the vision-reducing macular edema by intravitreal injection of inhibitors of vascular endothelial growth factors (VEGF) or corticosteroids and laser photocoagulation for neovascular complications. As long as head-to-head studies comparing steroids and VEGF inhibitors have not been published, none of the available intravitreally injected substances can be given priority. Well-known side effects of intravitreal steroids are cataract formation and ocular hypertension whereas VEGF inhibitors need to be frequently injected. Although therapy for retinal vein occlusion is protracted, initial long-term data indicate that treatment can be terminated in at least half of the patients . Finally, a treatment recommendation according to the current state of data is presented. PMID:26242852

  12. Embolization of internal carotid artery for carotid-cavernous fistula with laminaria

    International Nuclear Information System (INIS)

    The advanced method for treatment of carotid-cavernous fistula, is selective occlusion of fistula by detachable balloon catheter, with maintaining blood flow in ipsilateral internal carotid artery. But some disadvantages are in this method, such as high cost for balloon catheter, and difficulty in the technique. Laminaria, root of sea plant, has a character, which is expanded in humidity, about 3-4 times than in dry condition. Lim et al suggested that laminaria made thrombus in a artery without adversed reaction in animal study. Laminaria, as embolus, has some advantages, which are low cost, easy modelling, and it's specific character. So authors made it small club shape for occlusion of internal carotid artery at fistula level, just likely trapping method in surgery. Tail portion of the club was inserted into the tip of guiding catheter (7F multipurpose, Cordis), and advanced to cavernous portion of internal carotid artery via catheter introducing sheath from femoral artery or from common carotid artery. And then at the portion of fistula, embolus was detached with guide wire. For 10 months, we have tried the embolization at 4 cases of traumatic CCF. 3 cases were succeeded, and one was failed and in death. He had very tortuous vessels, so that laminaria could not be reached at the fistula level, only petrous portion. And now we suggested a new method and a embolic material for treatment of carotid-cavernous fistula, which has low cost and simple technique

  13. Reliability of retinal vessel calibre measurements using a retinal oximeter

    OpenAIRE

    Heitmar, Rebekka; Kalitzeos, Angelos A.

    2015-01-01

    Background Summarised retinal vessel diameters are linked to systemic vascular pathology. Monochromatic images provide best contrast to measure vessel calibres. However, when obtaining images with a dual wavelength oximeter the red-free image can be extracted as the green channel information only which in turn will reduce the number of photographs taken at a given time. This will reduce patient exposure to the camera flash and could provide sufficient quality images to reliably measure vessel...

  14. The effect of intravitreal bevacizumab on ocular blood flow in diabetic retinopathy and branch retinal vein occlusion as measured by laser speckle flowgraphy

    Directory of Open Access Journals (Sweden)

    Nitta F

    2014-06-01

    Full Text Available Fumihiko Nitta,1 Hiroshi Kunikata,1,2 Naoko Aizawa,1 Kazuko Omodaka,1 Yukihiro Shiga,1 Masayuki Yasuda,1 Toru Nakazawa1–31Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan; 2Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Sendai, Japan; 3Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Sendai, JapanBackground: This study evaluated the effect of intravitreal injection of bevacizumab (IVB on macular edema associated with diabetic retinopathy (DME or branch retinal vein occlusion (BRVOME using laser speckle flowgraphy.Methods: A comparative interventional study of 25 eyes from 22 patients with macular edema (DME group: 12 eyes; BRVOME group: 13 eyes who underwent IVB. Mean blur rate (MBR was measured in the retinal artery, retinal vein, optic nerve head (ONH, and choroid before and after IVB. Results: In the BRVOME group, there was no significant change in MBR in the retinal artery, retinal vein or ONH, but choroidal MBR decreased significantly (P=0.04. In the DME group, the MBR in the retinal artery, retinal vein, ONH, and choroid decreased significantly (P=0.02, P=0.04, P<0.001, and P=0.04, respectively. In the DME group, pre-IVB MBR in the ONH was significantly correlated with post-IVB foveal thickness (R= -0.71, P=0.002. There was no such correlation in the BRVOME group in the ONH.Conclusion: IVB had a suppressive effect on circulation in eyes with DME but not in those with BRVOME. This suggests that this noninvasive and objective biomarker may be a useful part of pre-IVB evaluations and decision-making in DME.Keywords: macular edema, mean blur rate, optic nerve head, biomarker, ocular circulation

  15. Prevalence of generalized retinal dystrophy in Denmark

    DEFF Research Database (Denmark)

    Bertelsen, Mette; Jensen, Hanne; Bregnhøj, Jesper F; Rosenberg, Thomas

    2014-01-01

    study was to examine the prevalence and diagnostic spectrum of generalized retinal dystrophy in the Danish population. METHODS: A population-based cross-sectional study with data from the Danish Retinitis Pigmentosa Registry that comprises all patients in Denmark with generalized retinal and......PURPOSE: Generalized retinal dystrophy is a frequent cause of visual impairment and blindness in younger individuals and a subject of new clinical intervention trials. Nonetheless, there are few nation-wide population-based epidemiological data of generalized retinal dystrophy. The purpose of this...... chorioretinal dystrophies from the 19th century to the present. Among 3076 registered cases, the primary diagnosis of generalized retinal dystrophy was assessed by chart review, including fundus photographs and electroretinograms. Demographic data on the Danish population were retrieved from Statistics Denmark...

  16. Advances in Retinal Stem Cell Biology

    Directory of Open Access Journals (Sweden)

    Andrea S Viczian

    2013-01-01

    Full Text Available Tremendous progress has been made in recent years to generate retinal cells from pluripotent cell sources. These advances provide hope for those suffering from blindness due to lost retinal cells. Understanding the intrinsic genetic network in model organisms, like fly and frog, has led to a better understanding of the extrinsic signaling pathways necessary for retinal progenitor cell formation in mouse and human cell cultures. This review focuses on the culture methods used by different groups, which has culminated in the generation of laminated retinal tissue from both embryonic and induced pluripotent cells. The review also briefly describes advances made in transplantation studies using donor retinal progenitor and cultured retinal cells.

  17. Current perspectives of herpesviral retinitis and choroiditis.

    Science.gov (United States)

    Madhavan, H N; Priya, K; Biswas, J

    2004-10-01

    Vision-threatening viral retinitis are primarily caused by members of the herpesvirus family. The biology and molecular characterization of herpesviruses, clinical presentations of retinopathies, pathology and pathogenesis including the host responses, epidemiology and the laboratory methods of aetiological diagnosis of these diseases are described. Clinical syndromes are acute retinal necrosis (ARN), progressive outer retinal necrosis (PORN), cytomegalovirus (CMV) retinitis, multifocal choroiditis and serpiginous choroiditis besides other viral retinopathies. Herpes simplex virus (HSV) retinitis is more common in immunocompetent persons while varicella zoster virus (VZV) affects both immunocompetent and immunosuppressed patients equally. CMV retinitis is most common among patients with AIDS. The currently employed laboratory methods of antigen detection, virus isolation and antibody detection by enzyme linked immuno-sorbent assay (ELISA) have low sensitivity. Polymerase chain reaction (PCR) has increased the value of diagnosis due to its high clinical sensitivity and absolute specificity in detection of herpesviruses in intraocular specimens. PMID:16295367

  18. Retinal Detachment: What Is a Torn or Detached Retina?

    Science.gov (United States)

    ... Eyes & the Sun Eye Health News Consumer Alerts Retinal Detachment: What Is a Torn or Detached Retina? Tweet ... stars.” These are called flashes. Retinal tear and retinal detachment Usually, the vitreous moves away from the retina ...

  19. [Prophylactic treatment of retinal detachment].

    Science.gov (United States)

    Binder, S; Riss, B

    1981-08-01

    The indications for and results of prophylactic treatment of retinal detachment during a period of five years are reported and compared with the results in the literature. Half of the cases (3 out of 6 eyes) which developed a retinal detachment had been horse-shoe tears combined with a vitreous hemorrhage. For this reason a small buckle operation is recommended in these cases, to prevent further traction. Lattice degeneration should rather be observed than treated, except in special cases: This includes eyes where the fellow eye had a detachment from a lattice degeneration, cases in which one eye is blind from an uncured detachment or has no useful visual acuity, and eyes whose fellow eye has giant tears. In aphakic eyes treatment of lattice degeneration is recommended, because the incidence of detachment from these areas is high, especially in young aphakic cases. In one aphakic eye which had been photocoagulated several times the formation of a preretinal membrane was observed. PMID:7347786

  20. Combined retinal detachment and candida chorioretinitis

    OpenAIRE

    Vela, José I.; Roselló, Noemí; Díaz-Cascajosa, Jesús; Crespí, Jaume; Buil, José A.

    2010-01-01

    To report a case of slowly progressive traction and rhegmatogenous retinal detachment after successfully managed candida chorioretinitis. A 44-year-old immunocompromised woman was treated with voriconazole for fungal chorioretinitis. Six months after onset she developed a combined retinal detachment. Slow progression of retinal detachment was observed and vitrectomy was performed. The macular area remained attached and visual acuity was maintained. Ophthalmologists should be aware of this unu...

  1. Photovoltaic Retinal Prosthesis with High Pixel Density

    OpenAIRE

    Mathieson, Keith; Loudin, James; Goetz, Georges; Huie, Philip; Wang, Lele; Kamins, Theodore I.; Galambos, Ludwig; Smith, Richard; Harris, James S.; Sher, Alexander; Palanker, Daniel

    2012-01-01

    Retinal degenerative diseases lead to blindness due to loss of the “image capturing” photoreceptors, while neurons in the “image processing” inner retinal layers are relatively well preserved. Electronic retinal prostheses seek to restore sight by electrically stimulating surviving neurons. Most implants are powered through inductive coils, requiring complex surgical methods to implant the coil-decoder-cable-array systems, which deliver energy to stimulating electrodes via intraocular cables....

  2. BLOOD VESSEL DIAMETER MEASUREMENT ON RETINAL IMAGE

    OpenAIRE

    Nidhal El Abbadi; Enas Al Saadi

    2014-01-01

    Accurate measurement of vessel diameters on retinal images plays an important part in diagnosing cardiovascular diseases and early signs of certain systemic diseases, such as diabetes and hypertension. In this study we develop new method based on computer aided to determine the width of retinal blood vessels by analysing the color fundus image. Retinal vessel diameter was measured based on blood vessel wall estimating on the digital fundus image. We suggested a dependable and accurate techniq...

  3. Retinal Image Matching Using Hierarchical Vascular Features

    OpenAIRE

    Wong, Tien Y; Kotagiri Ramamohanarao; Baikunth Nath; Ecosse Lamoureux; Alauddin Bhuiyan

    2011-01-01

    We propose a method for retinal image matching that can be used in image matching for person identification or patient longitudinal study. Vascular invariant features are extracted from the retinal image, and a feature vector is constructed for each of the vessel segments in the retinal blood vessels. The feature vectors are represented in a tree structure with maintaining the vessel segments actual hierarchical positions. Using these feature vectors, corresponding images are matched. The met...

  4. Prothrombin time in retinitis pigmentosa

    Directory of Open Access Journals (Sweden)

    Vinchurkar Manisha

    1998-01-01

    Full Text Available The prothrombin time was recorded for 87 primary retinitis pigmentosa (RP patients belonging to three different clinical categories. All categories showed prothrombin time higher than normal. There was no correlation between the age of onset and the prothrombin time, nor between duration of disease and the prothrombin time. The high prothrombin time in patients with RP suggests that further study of prothrombin time and related factors may help in better understanding of the pathogenesis of RP.

  5. A Novel Retinal Identification System

    Directory of Open Access Journals (Sweden)

    Mohammad-Shahram Moin

    2008-05-01

    Full Text Available This paper presents a novel biometric identification system with high performance based on the features obtained from human retinal images. This system is composed of three principal modules including blood vessel segmentation, feature generation, and feature matching. Blood vessel segmentation module has the role of extracting blood vessels pattern from retinal images. Feature generation module includes the following stages. First, the optical disk is found and a circular region of interest (ROI around it is selected in the segmented image. Then, using a polar transformation, a rotation invariant template is created from each ROI. In the next stage, these templates are analyzed in three different scales using wavelet transform to separate vessels according to their diameter sizes. In the last stage, vessels position and orientation in each scale are used to define a feature vector for each subject in the database. For feature matching, we introduce a modified correlation measure to obtain a similarity index for each scale of the feature vector. Then, we compute the total value of the similarity index by summing scale-weighted similarity indices. Experimental results on a database, including 300 retinal images obtained from 60 subjects, demonstrated an average equal error rate equal to 1 percent for our identification system.

  6. Stem cell-based therapeutic applications in retinal degenerative diseases

    OpenAIRE

    Huang, Yiming; Enzmann, Volker; Suzanne T. Ildstad

    2011-01-01

    Retinal degenerative diseases that target photoreceptors or the adjacent retinal pigment epithelium (RPE) affect millions of people worldwide. Retinal degeneration (RD) is found in many different forms of retinal diseases including retinitis pigmentosa (RP), age-related macular degeneration (AMD), diabetic retinopathy, cataracts, and glaucoma. Effective treatment for retinal degeneration has been widely investigated. Gene-replacement therapy has been shown to improve visual function in inheri...

  7. Retinal Cell Degeneration in Animal Models

    Science.gov (United States)

    Niwa, Masayuki; Aoki, Hitomi; Hirata, Akihiro; Tomita, Hiroyuki; Green, Paul G.; Hara, Akira

    2016-01-01

    The aim of this review is to provide an overview of various retinal cell degeneration models in animal induced by chemicals (N-methyl-d-aspartate- and CoCl2-induced), autoimmune (experimental autoimmune encephalomyelitis), mechanical stress (optic nerve crush-induced, light-induced) and ischemia (transient retinal ischemia-induced). The target regions, pathology and proposed mechanism of each model are described in a comparative fashion. Animal models of retinal cell degeneration provide insight into the underlying mechanisms of the disease, and will facilitate the development of novel effective therapeutic drugs to treat retinal cell damage. PMID:26784179

  8. Acute retinal ischemia caused by controlled low ocular perfusion pressure in a porcine model. Electrophysiological and histological characterisation

    DEFF Research Database (Denmark)

    Kyhn, Maria Voss; Warfvinge, Karin; Scherfig, Erik; Kiilgaard, Jens F; Prause, Jan Ulrik; Klassen, Henry; Young, Michael; la Cour, Morten

    2009-01-01

    The purpose of this study was to establish, and characterize a porcine model of acute, controlled retinal ischemia. The controlled retinal ischemia was produced by clamping the ocular perfusion pressure (OPP) in the left eye to 5 mm Hg for 2 h. The OPP was defined as mean arterial blood pressure (MAP) minus the intraocular pressure (IOP). It was clamped to 0-30 mm Hg by continuous monitoring of MAP and adjustment of the IOP, which was controlled by cannulation of the anterior chamber. Inner reti...

  9. Ophthalmic systems completely supplied from dural arteries indicate the utility of endovascular treatment of cerebral aneurysms.

    Science.gov (United States)

    Kadooka, Keisuke; Tanaka, Michihiro

    2015-12-01

    We report a 67-year-old man who harboured an unruptured left basilar-superior cerebellar artery aneurysm. Cerebral angiography and cone beam computed tomography with diluted contrast medium showed that the bilateral ophthalmic arteries were not supplied from internal carotid arteries but, rather, were supplied from the middle meningeal and accessory meningeal arteries. This meant that the ophthalmic system was predominantly supplied from the dural arteries and, therefore, pterional craniotomy might cause a compromise in blood supply to the retinal artery. To avoid this complication, coil embolization was selected instead of neck clipping, and this endovascular therapy succeeded without neurological deficit. This case report shows the importance of cerebral angiography (including cone beam computed tomography) and consideration of the patterns of ophthalmic artery perfusion when selecting operative procedures for management of aneurysms that require manipulation around the sphenoid ridge. PMID:26472634

  10. Retinal vascular calibre and response to light exposure and serial imaging

    DEFF Research Database (Denmark)

    von Hanno, T.; SjØlie, Anne K.

    2014-01-01

    Purpose: To investigate whether retinal vessel calibre measurements on optical retinal photography are affected by light and dark exposure prior to photography and whether the vessel calibre changes during an imaging sequence of several images. Methods: Digital optical retinal photographs were obtained from 32 healthy adults in two separate image sequences of six images during 1 min; one sequence with 10 min of dark exposure and one with 10 min of light exposure prior to imaging. Retinal arteriolar and venular calibres were measured computer-assisted and summarized as central retinal artery and vein equivalents (CRAE and CRVE). Outcome measures were difference in calibres after prior light versus prior dark exposure and difference in calibre during each of the two imaging sequences. Results: CRVE was wider with prior light exposure (2.7%, p = 0.0001), comparing the first image in each image sequence. Within each sequence, there was a venular dilatation from first to last image, both with prior light exposure (1.7%, p = 0.0003) and prior dark exposure (3.1%, p <0.0001), with the change less pronounced with prior light exposure (p = 0.0164). CRAE showed no significant change in either outcome. Conclusions: Retinal venular calibre was wider with light exposure prior to imaging and increased slightly during the imaging sequences, less pronounced after prior light than dark exposure. Measurement error due to these effects will probably be reduced by avoiding dark prior to imaging, and a possible bias effect of endothelial dysfunction may possibly be reduced by measuring calibre on an image taken early in the image sequence.

  11. Retinal arterioles have impaired reactivity to hyperoxia in type 1 diabetes

    DEFF Research Database (Denmark)

    Justesen, Birgitte L; Mistry, Paresh

    2010-01-01

    PURPOSE: Diabetes has adverse effects on the retinal microvasculature. The purpose of this study was to compare the effects of inhalation of hypoxic, hyperoxic and normoxic-hypercapnic gas mixtures on retinal vessel diameter in people with and without diabetes. METHODS: Sixty-one participants (aged 24-50 years) 29 with (male : female ratio 2.6 : 1) and 32 without (male : female ratio 0.7 : 1) diabetes, inhaled hypoxic, hyperoxic and normoxic-hypercapnic gas mixtures for 3-5 mins. The diameters of arterioles and venules were measured using digital retinal images taken before and after gas inhalation. RESULTS: There was no significant difference in the diameters of arterioles and venules prior to gas inhalation in people with and without diabetes. Inhalation of the hyperoxic gas mixture caused a statistically significant decrease in arteriolar and venular diameters without altering mean arterial pressure significantly. Arteriolar vasoconstriction in response to the hyperoxic gas mixture was significantly reduced in people with diabetes (3.95% versus 7.75%; p = 0.04), but venular vasoconstriction did not differ significantly. A hypoxic gas mixture caused increased arteriolar and venular diameter and a normoxic-hypercapnic gas mixture had no significant effect on vessel diameter. Responses to hypoxic and normoxic-hypercapnic gas did not differ significantly between diabetes and non-diabetes subjects. CONCLUSIONS: Type 1 diabetes impairs retinal arteriolar responses to hyperoxia. Abnormalities in retinal arteriolar reactivity in response to oxygen may play a role in the development of diabetic retinopathy and this technique may represent a simple means of identifying early abnormalities in the reactivity of retinal arterioles in diabetes.

  12. Reconstruction of the internal iliac artery in patients with aneurysmal disease: Two case reports.

    Science.gov (United States)

    Joh, Jin Hyun; Park, Ho-Chul

    2014-03-01

    During the endovascular repair of aortoiliac aneurysm, bilateral internal iliac artery (IIA) occlusion may give rise to significant morbidities such as ischemia of buttock or sigmoid colon and erectile dysfunction. Open and endovascular approaches are used to maintain IIA circulation in such cases. The present report describes the cases of two patients who underwent external-to-internal iliac artery bypass surgery, one via a novel hybrid approach. The first patient had a right common iliac artery aneurysm without a sufficient distal landing zone for endovascular repair. The distal landing of the device was therefore placed in the right external iliac artery (EIA). The tortuous portion of the right EIA was excised and anastomosed in an end-to-end fashion. An external-to-internal iliac artery bypass was then performed. The second patient underwent endovascular repair of the IIA aneurysm with a Gore(®) Viabahn(®)-covered stent (W. L. Gore and Associates, Inc., Flagstaff, AZ, USA). This covered stent was anastomosed with the iliac bypass graft. Postoperative pelvic circulation was maintained. In conclusion, this strategy for maintaining IIA flow is a potential novel approach for future use. PMID:24520248

  13. ALTAIR: Supervised Methodology to Obtain Retinal Vessels Caliber

    Directory of Open Access Journals (Sweden)

    Pablo CHAMOSO

    2014-12-01

    Full Text Available A back of the eye examination allows performing a noninvasive evaluation of the retinal microcirculation, as well as of the vascular damage induced by multiple cardiovascular risk factors. The objective of this work is to study the existing needs to lead to the development and validation (reliability and validity of a methodology able to extract all the information from the images of the back of the eye to solve the studied needs. Its development will subsequently allow analyzing its utility in various clinical environments. Currently there are different works that evaluate the thickness of the retinal veins and arteries, but they require either full intervention by an observer or no intervention at all, so when facing incorrect analysis (none of them achieves a 100 % accuracy in automatic analysis erroneous results can be a serious problem when drawing conclusions. The proposed solution refers to the second group (automatic, but providing a supervisor the possibility to interfere with the analysis when any kind of error is produced, which ideally will not happen many times. Thanks to this the possible subjectivity that can be introduced by the supervisor does not affect the final result of the analysis.

  14. Prevalence of generalized retinal dystrophy in Denmark

    DEFF Research Database (Denmark)

    Bertelsen, Mette; Jensen, Hanne

    2014-01-01

    PURPOSE: Generalized retinal dystrophy is a frequent cause of visual impairment and blindness in younger individuals and a subject of new clinical intervention trials. Nonetheless, there are few nation-wide population-based epidemiological data of generalized retinal dystrophy. The purpose of this study was to examine the prevalence and diagnostic spectrum of generalized retinal dystrophy in the Danish population. METHODS: A population-based cross-sectional study with data from the Danish Retinitis Pigmentosa Registry that comprises all patients in Denmark with generalized retinal and chorioretinal dystrophies from the 19th century to the present. Among 3076 registered cases, the primary diagnosis of generalized retinal dystrophy was assessed by chart review, including fundus photographs and electroretinograms. Demographic data on the Danish population were retrieved from Statistics Denmark. RESULTS: Of the 5,602,628 Danish citizens on January 1, 2013, 1622 patients were registered as having a generalized retinal dystrophy and were alive and living in Denmark, corresponding to a prevalence of 1:3,454. In 28% of cases the eye condition was part of a syndrome, while the remaining 72% had eye disease only. Aside from simplex cases (45%), the most common hereditary pattern was autosomal recessive (23%). CONCLUSION: This epidemiological survey demonstrates that the prevalence of generalized retinal dystrophy in the Danish population is 1:3454. Many of the dystrophies are the subjects of clinical intervention trials, and nation-wide epidemiological data can help assess the burden of the disease and the future need for treatment.

  15. [Viral retinitis following intravitreal triamcinolone injection].

    Science.gov (United States)

    Zghal, I; Malek, I; Amel, C; Soumaya, O; Bouguila, H; Nacef, L

    2013-09-01

    Necrotizing viral retinitis is associated with infection by the Herpes family of viruses, especially herpes simplex virus (HSV), varicella zoster virus (VZV) and occasionally cytomegalovirus (CMV). When the diagnosis is suspected clinically, antiviral therapy must be instituted immediately. We report the case of a patient presenting with necrotizing viral retinitis 3 months following intravitreal injection of triamcinolone acetonide for diabetic macular edema. Fluorescein angiography demonstrated a superior temporal occlusive vasculitis. A diagnostic anterior chamber paracentesis was performed to obtain deoxyribo-nucleic acid (DNA) for a polymerase chain reaction (PCR) test for viral retinitis. PCR was positive for CMV. The patient was placed on intravenous ganciclovir. CMV retinitis is exceedingly rare in immunocompetent patients; however, it remains the most common cause of posterior uveitis in immunocompromised patients. The incidence of this entity remains unknown. Local immunosuppression, the dose and the frequency of injections may explain the occurrence of this severe retinitis. PMID:23648134

  16. Regenerative Therapy for Retinal Disorders

    Directory of Open Access Journals (Sweden)

    Narsis Daftarian

    2010-01-01

    Full Text Available Major advances in various disciplines of basic sciences including embryology, molecular and cell biology, genetics, and nanotechnology, as well as stem cell biology have opened new horizons for regenerative therapy. The unique characteristics of stem cells prompt a sound understanding for their use in modern regenerative therapies. This review article discusses stem cells, developmental stages of the eye field, eye field transcriptional factors, and endogenous and exogenous sources of stem cells. Recent studies and challenges in the application of stem cells for retinal pigment epithelial degeneration models will be summarized followed by obstacles facing regenerative therapy.

  17. Energetic and spatial constraints of arterial networks

    Directory of Open Access Journals (Sweden)

    Sandro Rossitti

    1995-06-01

    Full Text Available The principle of minimum work (PMW is a parametric optimization model for the growth and adaptation of arterial trees. A balance between energy dissipation due to frictional resistance of laminar flow (shear stress and the minimum volume of the blood and vessel wall tissue is achieved when the vessel radii are adjusted to the cube root of the volumetric flow. The PMW is known to apply over several magnitudes of vessel calibers, and in many different organs, including the brain, in humans and in animals. Animal studies suggest that blood flow in arteries is approximately proportional to the cube of the vessel radius, and that arteries alter their caliber in response to sustained changes of blood flow according to PMW. Remodelling of the retinal arteriolar network to long-term changes in blood flow was observed in humans. Remodelling of whole arterial networks occurs in the form of increase or diminishing of vessel calibers. Shear stress induced endothelial mediation seems to be the regulating mechanism for the maintenance of this optimum blood flow/vessel diameter relation. Arterial trees are also expected to be nearly space filing. The vascular system is constructed in such a way that, while blood vessels occupy only a small percentage of the body volume leaving the bulk to tissue, they also crisscross organs so tightly that every point in the tissue lies on the boundary between an artery and a vein. This review describes how the energetic optimum principle for least energy cost for blood flow is also compatible with the spatial constraints of arterial networks according to concepts derived from fractal geometry.

  18. Retinal Detachment and Proliferative Vitreoretinopathy.

    Science.gov (United States)

    Kwon, Oh Woong; Song, Ji Hun; Roh, Mi In

    2016-01-01

    In normal eyes, retinal detachment (RD) occurs at a rate of approximately 5 per 100,000 people per year and the frequency of proliferative vitreoretinopathy (PVR) remains largely unchanged in primary RD, with the incidence ranging from 5.1 to 11.7%. PVR is the most common cause of failed repair of rhegmatogenous RD, and risk factors for PVR are related to several well-known pre-, intra-, and postoperative clinical situations. Current methods of surgical management of RD and PVR are pneumatic retinopexy, scleral buckling, and pars plana vitrectomy (PPV). Surgical success rates for PVR have improved as techniques and instruments of vitrectomy evolved. However, despite these advances, more than one fourth of initially successful cases results in redetachment due to recurrent vitreoretinal traction. Retinal pigment epithelial cells are the key factor in triggering PVR development. In addition, soluble mediators and the extracellular matrix components play a critical role in cellular events, including proliferation and tissue contraction which occur in PVR. Although PPV remains a critical component of the treatment in RD and PVR, ongoing efforts seek to identify adjuvant therapies that might inhibit PVR development. Recent studies have therefore been directed toward pharmacologic inhibition of cellular proliferation and membrane contraction with drugs such as daunorubicin, 5-fluorouracil, and heparin. More detailed understanding of the pathophysiology underlying PVR may lead to the development of effective prophylactic and/or adjunctive therapies. Further work is necessary to identify optimal adjunctive therapies for the management of RD and PVR. PMID:26501375

  19. A Pilot Study of Uterine Artery Embolization with Tris-Acryl Gelatin Microspheres in Guinea Pigs

    International Nuclear Information System (INIS)

    Objective: This study was designed to establish guinea pigs as an animal model for uterine artery embolization (UAE) with tris-acryl gelatin microspheres (TAGM). Methods: Twenty-five female adult guinea pigs were randomly divided into two groups, including a uterine artery casting mould group (n = 10) and a UAE group (n = 15). Pelvic angiography and vascular casting mould were performed in the first group. The anatomical characters of the pelvic cavity in guinea pigs were described. In the second group, the technical feasibility of performing UAE with TAGM in guinea pigs was investigated. The histopathological slides of the uterus of guinea pigs after UAE were examined to inspect the outcomes of UAE. Results: The uterine artery springs from the internal iliac artery, ascends tortuously along the cervix, and gives off vertically 8–10 branches to the cervix uteri and uterine horns. The diameters of the trunk of the uterine artery and its first branch were 0.32 ± 0.027 mm and 0.14 ± 0.01 mm, respectively. For UAE animals, the dosages of 40–120 and 100–300 ?m TAGM were 0.033 ± 0.003 ml and 0.015 ± 0.002 ml, respectively. On histopathological slides, embosphere particles were found in the first branches of the uterine artery, the subserous arteries, and the intramural arteries. Inflammatory reactions in the uterus were common in guinea pigs after UAE. Local or dispersed areas of necrosis in uterus also were observed in a few guinea pigs. Conclusions: Guinea pigs are an appropriate and feasible model for UAE with TAGM.

  20. Retinal microvascular network attenuation in Alzheimer's disease

    Science.gov (United States)

    Williams, Michael A.; McGowan, Amy J.; Cardwell, Chris R.; Cheung, Carol Y.; Craig, David; Passmore, Peter; Silvestri, Giuliana; Maxwell, Alexander P.; McKay, Gareth J.

    2015-01-01

    Introduction Cerebral small-vessel disease has been implicated in the development of Alzheimer's disease (AD). The retinal microvasculature enables the noninvasive visualization and evaluation of the systemic microcirculation. We evaluated retinal microvascular parameters in a case-control study of AD patients and cognitively normal controls. Methods Retinal images were computationally analyzed and quantitative retinal parameters (caliber, fractal dimension, tortuosity, and bifurcation) measured. Regression models were used to compute odds ratios (OR) and confidence intervals (CI) for AD with adjustment for confounders. Results Retinal images were available in 213 AD participants and 294 cognitively normal controls. Persons with lower venular fractal dimension (OR per standard deviation [SD] increase, 0.77 [CI: 0.62–0.97]) and lower arteriolar tortuosity (OR per SD increase, 0.78 [CI: 0.63–0.97]) were more likely to have AD after appropriate adjustment. Discussion Patients with AD have a sparser retinal microvascular network and retinal microvascular variation may represent similar pathophysiological events within the cerebral microvasculature of patients with AD.

  1. [Primary vitrectomy in rhegmatogenous retinal detachment].

    Science.gov (United States)

    Höing, C; Heidenkummer, H P; Kampik, A

    1995-10-01

    For therapy of uncomplicated rhegmatogenous retinal detachment, a buckling procedure is the standard surgical technique today. In complicated cases, e.g., retinal redetachment after a failed buckling procedure, vitrectomy is established. Meanwhile it is being discussed whether or not certain retinal detachments, e.g., with atypically large tears, should be treated with primary vitrectomy. We studied retrospectively all primary vitrectomies for retinal detachment without proliferative vitreoretinopathy (PVR) that were operated upon during 1992 in Würzburg Eye Hospital (32 patients). In 56% (18 eyes) of the patients a subtotal or total retinal detachment was seen preoperatively; in 47% (15 eyes) the macular region was detached. In 25% (8 eyes) large retinal tears were seen (> 1 h). The other patients showed atypical horseshoe tears partly central to the equator or multiple holes. Seventy-eight percent (25 eyes) of all cases were successfully vitrectomized with one operation and revealed good results using intraocular tamponade (SF-6/air mixture). Seven patients needed further vitrectomy partly using silicone oil as an intraocular tamponade. In cases of rhegmatogenous retinal detachment with atypical tears or non-identified holes, vitrectomy without the buckling procedure is a good alternative, because the rate of successful results is as high as what is achieved with buckling procedure in uncomplicated cases. PMID:8750993

  2. A mechanical model of retinal detachment

    Science.gov (United States)

    Chou, Tom; Siegel, Michael

    2012-08-01

    We present a model of the mechanical and fluid forces associated with exudative retinal detachments where the retinal photoreceptor cells separate, typically from the underlying retinal pigment epithelium (RPE). By computing the total fluid volume flow arising from transretinal, vascular and RPE pump currents, we determine the conditions under which the subretinal fluid pressure exceeds the maximum yield stress holding the retina and RPE together, giving rise to an irreversible, extended retinal delamination. We also investigate localized, blister-like retinal detachments by balancing mechanical tension in the retina with both the retina-RPE adhesion energy and the hydraulic pressure jump across the retina. For detachments induced by traction forces, we find a critical radius beyond which the blister is unstable to growth. Growth of a detached blister can also be driven by inflamed lesions in which the tissue has a higher choroidal hydraulic conductivity, has insufficient RPE pump activity, or has defective adhesion bonds. We determine the parameter regimes in which the blister either becomes unstable to growth, remains stable and finite-sized, or shrinks, allowing possible healing. The corresponding stable blister radius and shape are calculated. Our analysis provides a quantitative description of the physical mechanisms involved in exudative retinal detachments and can help guide the development of retinal reattachment protocols or preventative procedures.

  3. Bilateral acute retinal necrosis after herpetic meningitis

    Directory of Open Access Journals (Sweden)

    Katsura T

    2012-04-01

    Full Text Available Keisho Hirota1,2, Masayuki Akimoto1,3, Toshiaki Katsura21Department of Ophthalmology, Kyoto Medical Center, National Hospital Organization, 2Internal Medicine, Kyoto Medical Center, 3Clinical Research Center, Kyoto Medical Center, Kyoto, JapanPurpose: The report of a case of bilateral acute retinal necrosis after herpetic meningitis.Case report: A 47-year-old man was admitted with the chief complaint of persistent high fever and transient loss of consciousness. Although his general condition improved after intravenous acyclovir administration, the patient presented with visual loss in both eyes 4 days after admission. Visual acuity in his right eye was 20/200 and his left eye had light perception alone. Both eyes showed panretinal arteritis diagnosed as acute retinal necrosis. Panretinal photocoagulation was performed for both eyes. Progression of retinal detachment was prevented in both eyes; however, visual acuity of the left eye was totally lost because of neovascular glaucoma. Visual acuity of the right eye recovered to 20/20.Conclusion: Although cases of bilateral acute retinal necrosis have been reported after herpetic encephalitis, this condition is rare after herpetic meningitis. Prophylactic acyclovir therapy and early panretinal photocoagulation may prevent retinal detachment and improve the prognosis. Neurologists and ophthalmologists should be aware that not only herpetic encephalitis but also herpetic meningitis can lead to acute retinal necrosis within a very short interval.Keywords: acute retinal necrosis, herpetic meningitis, herpes simplex, varicella zoster virus

  4. Mesenteric artery ischemia

    Science.gov (United States)

    ... ischemia is often seen in people who have hardening of the arteries in other parts of the ... long-term (chronic) mesenteric artery ischemia caused by hardening of the arteries ( atherosclerosis ): Abdominal pain after eating ...

  5. Peripheral arterial line (image)

    Science.gov (United States)

    A peripheral arterial line is a small, short plastic catheter placed through the skin into an artery of the arm or leg. The purpose of a peripheral arterial line is to allow continuous monitoring of blood pressure ...

  6. Coronary artery disease (image)

    Science.gov (United States)

    ... through these arteries is critical for the heart. Coronary artery disease usually results from the build-up of fatty material and plaque, a condition called atherosclerosis. As the coronary arteries narrow, the flow of blood to the ...

  7. Management of retinal detachment associated with CMV retinitis in AIDS patients.

    Science.gov (United States)

    Chuang, E L; Davis, J L

    1992-01-01

    In patients with AIDS, the most important ocular opportunistic infection, CMV retinitis, can now be treated effectively with virostatic agents. Associated retinal detachment is encountered frequently, and its management has become increasingly significant to quality of life as improvements in medical care have helped to preserve vision and extend life expectancy. Although retinal detachment in these eyes is typically rhegmatogenous, the pathophysiology is distinctive due to the association with CMV retinitis which, even in remission, is characterised by atrophic changes at all levels of affected retina and alterations of the vitreous. Despite initially successful surgical reattachment, multiple, small, often posterior holes may develop because of progressive CMV infection. For these reasons, vitrectomy and silicone oil injection with scleral buckling may currently provide the best overall means of maintaining retinal reattachment and restoring visual function. Nevertheless, management must be individualised in each case, with the realisation that progressive visual loss frequently ensues from retinitis progression. PMID:1330757

  8. Aging Changes in Retinal Microglia and their Relevance to Age-related Retinal Disease.

    Science.gov (United States)

    Ma, Wenxin; Wong, Wai T

    2016-01-01

    Age-related retinal diseases, such as age-related macular degeneration (AMD) and glaucoma, contain features of chronic retinal inflammation that may promote disease progression. However, the relationship between aging and neuroinflammation is unclear. Microglia are long-lived, resident immune cells of the retina, and mediate local neuroinflammatory reactions. We hypothesize that aging changes in microglia may be causally linked to neuroinflammatory changes underlying age-dependent retinal diseases. Here, we review the evidence for (1) how the retinal microglial phenotype changes with aging, (2) the factors that drive microglial aging in the retina, and (3) aging-related changes in microglial gene expression. We examine how these aspects of microglial aging changes may relate to pathogenic mechanisms of immune dysregulation driving the progression of age-related retinal disease. These relationships can highlight microglial aging as a novel target for the prevention and treatment of retinal disease. PMID:26427396

  9. Retinal changes detected by wide-field autofluorescence imaging of patients with primary rhegmatogenous retinal detachment

    DEFF Research Database (Denmark)

    Poulsen, Christina Døfler; Grauslund, Jakob; Peto, Tunde

    2014-01-01

    Titel: “Retinal changes detected by wide-field autofluorescence imaging of patients with primary rhegmatogenous retinal detachment” Purpose: To detect characteristic changes in autofluorescence (AF) images in patients with primary rhegmatogenous retinal detachment (RRD) and to compare these with...... tortuosity, rolled, irregular edge of tear), or C (full thickness retinal starfolds) , peroperative data, complications, Pelli Robson test, Ishihara and multifocal-ERG. Retinal changes in wide-field images were graded using fellow-eye as reference for normal appearance. Twenty-nine patients with major...... retinal changes, non-gradable images or surgery on fellow-eye were excluded to avoid potential incorrect grading. SD-OCT was used preoperatively to confirm whether fovea was attached or detached. P-value <0.05 was considered statistically significant. Results: Out of 99 eyes, 88 attended for baseline and...

  10. Automatic diagnosis of retinal diseases from color retinal images

    CERN Document Server

    Jayanthi, D; SwarnaParvathi, S

    2010-01-01

    Teleophthalmology holds a great potential to improve the quality, access, and affordability in health care. For patients, it can reduce the need for travel and provide the access to a superspecialist. Ophthalmology lends itself easily to telemedicine as it is a largely image based diagnosis. The main goal of the proposed system is to diagnose the type of disease in the retina and to automatically detect and segment retinal diseases without human supervision or interaction. The proposed system will diagnose the disease present in the retina using a neural network based classifier.The extent of the disease spread in the retina can be identified by extracting the textural features of the retina. This system will diagnose the following type of diseases: Diabetic Retinopathy and Drusen.

  11. Coronary arteries

    International Nuclear Information System (INIS)

    Coronary angiography (CA) is presently considered the gold standard for the assessment of the coronary arteries. However, the presence of ionizing radiation, its invasiveness and the small associated risk of morbidity prompted long ago the development of more patient-friendly imaging modalities. A promising technique, magnetic resonance imaging (MRI), has been regarded as the major modality in the coming decade. Although still in its infancy qualitatively, its flexibility and non-invasiveness opens the door for a comprehensive evaluation of the heart and the coronary arteries in one single sitting with high anatomical definition and excellent soft tissue contrast capabilities, double-oblique tomographic sections and the possibility to quantify an innumerable number of cardiovascular physiological parameters. Numerous ideas have been assessed, comprising breath-hold and free-breathing two-dimensional and three-dimensional measurements. New ongoing trials with intravascular contrast agents may provide for all these techniques the long-awaited essential boost for reliable magnetic resonance coronary angiography (MRCA). Introduction of parallel MRI acquisition techniques, such as simultaneous acquisition of spatial harmonics (SMASH) and sensitivity encoding (SENSE) may provide the speed enhancement required to shorten imaging time for all techniques explored to date. (orig.)

  12. Photostress Testing Device for Diagnosing Retinal Disease

    Directory of Open Access Journals (Sweden)

    Elizabeth Swan

    2014-08-01

    Full Text Available Retinal diseases such as Age-Related Macular Degeneration (ARMD affect nearly one in three elderly patients. ARMD damages the central vision photoreceptors in the fovea. The Photostress Test is a simple technique for testing for the early effects of ARMD. Here, the illumination sources in a novel self-administered Photostress Testing device were modeled for safety and distribution in illumination software. After satisfying the design constraints in the model, a prototype of the illumination system was fabricated and tested to confirm the modeling results. The resultant prototype can be used to aid in the diagnosis of retinal disease and is well within retinal safety levels.

  13. Histone Deacetylase: Therapeutic Targets in Retinal Degeneration.

    Science.gov (United States)

    Daly, Conor; Yin, Jun; Kennedy, Breandán N

    2016-01-01

    Previous studies report that retinitis pigmentosa (RP) patients treated with the histone deacetylase inhibitor (HDACi) valproic acid (VPA) present with improved visual fields and delayed vision loss. However, other studies report poor efficacy and safety of HDACi in other cohorts of retinal degeneration patients. Furthermore, the molecular mechanisms by which HDACi can improve visual function is unknown, albeit HDACi can attenuate pro-apoptotic stimuli and induce expression of neuroprotective factors. Thus, further analysis of HDACi is warranted in pre-clinical models of retinal degeneration including zebrafish. Analysis of HDAC expression in developing zebrafish reveals diverse temporal expression patterns during development and maturation of visual function. PMID:26427446

  14. Surgical treatment of central retinal vein occlusion.

    Science.gov (United States)

    Berker, Nilufer; Batman, Cosar

    2008-05-01

    The treatment of central retinal vein occlusion (CRVO) is still a subject of debate. Medical therapy efforts, as well as retinal laser photocoagulation, have mostly dealt with management of the sequelae of CRVO, and have shown limited success in improving visual acuity. The unsatisfactory results of such therapeutic efforts led to the development of new treatment strategies focused on the surgical treatment of the occluded retinal vein. The purpose of this review is to summarize the outcomes of commonly reported surgical treatment strategies and to review different opinions on the various surgical approaches to the treatment of CRVO. PMID:18494725

  15. Long-term outcomes in patients undergoing vitrectomy for retinal detachment due to viral retinitis

    Directory of Open Access Journals (Sweden)

    Almeida DRP

    2015-07-01

    Full Text Available David RP Almeida,1 Eric K Chin,1 Ryan M Tarantola,1 Elizabeth O Tegins,1 Christopher A Lopez,1 Herbert Culver Boldt,1 Karen M Gehrs,1 Elliott H Sohn,1 Stephen R Russell,1 James C Folk,1 Vinit B Mahajan1,2 1Department of Ophthalmology and Visual Sciences, 2Omics Laboratory, University of Iowa Hospitals and Clinics, Iowa City, IA, USA Purpose: To determine the outcomes in patients with rhegmatogenous retinal detachment (RRD secondary to viral retinitis. Patients and methods: This was a retrospective, consecutive, noncomparative, interventional case series of 12 eyes in ten patients with RRD secondary to viral retinitis. Results of vitreous or aqueous biopsy, effect of antiviral therapeutics, time to retinal detachment, course of visual acuity, and anatomic and surgical outcomes were investigated. Results: There were 1,259 cases of RRD during the study period, with 12 cases of RRD secondary to viral retinitis (prevalence of 0.95%. Follow-up was available for a mean period of 4.4 years. Varicella zoster virus was detected in six eyes, herpes simplex virus in two eyes, and cytomegalovirus in two eyes. Eight patients were treated with oral valacyclovir and two patients with intravenous acyclovir. Lack of optic nerve involvement correlated with improved final visual acuity of 20/100 or greater. Pars plana vitrectomy (n=12, silicone-oil tamponade (n=11, and scleral buckling (n=10 provided successful anatomic retinal reattachment in all cases, with no recurrent retinal detachment and no cases of hypotony during the follow-up period. Conclusion: Varicella zoster virus was the most frequent cause of viral retinitis, and lack of optic nerve involvement was predictive of a favorable visual acuity prognosis. Vitrectomy with silicone-oil tamponade and scleral buckle placement provided stable anatomical outcomes. Keywords: viral retinitis, acute retinal necrosis, herpetic retinitis, vitrectomy, retinal detachment 

  16. Hypoxia-inducible factor and vascular endothelial growth factor in the neuroretina and retinal blood vessels after retinal ischemia

    DEFF Research Database (Denmark)

    Håkansson, Gisela; Gesslein, Bodil; Gustafsson, Lotta; Englund-Johansson, Ulrica; Malmsjö, Malin

    2010-01-01

    Retinal ischemia arises from circulatory failure. As the retinal blood vessels are key organs in circulatory failure, our aim was to study the retinal vasculature separately from the neuroretina to elucidate the role of hypoxia-inducible factor (HIF) 1? and 1? and vascular endothelial growth factor (VEGF) in retinal ischemia. Retinal ischemia was induced in porcine eyes by applying an intraocular pressure, followed by 12 h of reperfusion. HIF-1? mRNA expression was not affected by ischemia, whil...

  17. Retinal Remodeling in the Tg P347L Rabbit, a Large-Eye Model of Retinal Degeneration

    OpenAIRE

    Jones, Bryan William; Kondo, Mineo; Terasaki, Hiroko; Watt, Carl Brock; Rapp, Kevin; Anderson, James; Lin, Yanhua; Shaw, Marguerite Victoria; Yang, Jia-Hui; Marc, Robert Edward

    2011-01-01

    Retinitis pigmentosa (RP) is an inherited blinding disease characterized by progressive loss of retinal photo-receptors. There are numerous rodent models of retinal degeneration, but most are poor platforms for interventions that will translate into clinical practice. The rabbit possesses a number of desirable qualities for a model of retinal disease including a large eye and an existing and substantial knowledge base in retinal circuitry, anatomy, and ophthalmology. We have analyzed degenera...

  18. Arterial stenosis following radiotherapy

    International Nuclear Information System (INIS)

    Published reports of arterial stenosis following radiotherapy are reviewed. In oncological practice, this complication is rare but experimental studies have demonstrated the role of irradiation in producing arterial lesions. The histological specificity and the mechanisms of radiation and related arterial lesions are discussed. Atherosclerosis risk factors and chemotherapy could have a synergic role on artery stenosis. Cases reported of arterial stenosis after radiotherapy include subclavicular artery after breast cancer, carotid artery after head and neck cancer, coronary artery and abdominal aorta or its trunks after pelvic and abdominal irradiation. The radiotherapy parameters described are not unusual. Therapeutical modalities and their indications are presented

  19. Radial Artery Catheterization

    Science.gov (United States)

    ... by Shah, P. B. Related Content Load related Internet Resources information Social Bookmarking ... This Article Top Introduction Advantages of Radial Artery Catheterization The Radial Artery Catheterization ...

  20. Dolicomegarterias ilíacas.: Presentación de un caso. / Iliac mega-dolicho arteries: Presentation of a case

    Scientific Electronic Library Online (English)

    Yariana, Martínez Sánchez; Enélida, Matos Abrahantes; Juliana M, Tarajano Márquez; Jacqueline, Ramos Serpa; José Antonio, Rodríguez González.

    2010-02-01

    Full Text Available Las anomalías del árbol vascular son comunes. Los aneurismas aislados de las arterias ilíacas son de observación bastante rara. Representan un porcentaje escaso de las distintas estadísticas y a menudo se resalta su aislamiento, precisamente para recordar su rareza. Reportamos un caso masculino, de [...] 74 años de edad, que asistió a consulta por presentar síntomas urinarios. Se le realizó un ultrasonido de abdomen, observándose hidronefrosis renal bilateral moderada, además masas complejas una en cada fosa ilíaca. Se le indicó Tomografía Axial Computarizada de abdomen, donde se confirmó la hidronefrosis renal bilateral y aneurismas de ambas arterias ilíacas. Se completó el estudio con un Angiotac, y se demostró que ambas ilíacas estaban tortuosas y dilatadas (DOLICOMEGARTERIAS). Abstract in english Vascular tree anomalies are common. Iliac arteries isolated aneurisms are very unusual. They represent an scarce percent of the different statistics and their isolation is frequently highlighted, precisely to recollect their rareness.We report the case of a male, 74-years-old patient, assisting the [...] consultation with urinary symptoms. An abdominal ultrasound was made, showing moderated bilateral renal hydronephrosis and also complex masses in each iliac fosse. An abdomen computed axial tomography was indicated, confirming the bilateral renal hydronephrosis and aneurisms in both iliac arteries. The study was completed with an Angiotac and it was demonstrated that both iliac arteries were tortuous and dilated ( Mega-dolicho arteries ).

  1. Dolicomegarterias ilíacas.: Presentación de un caso. Iliac mega-dolicho arteries: Presentation of a case

    Directory of Open Access Journals (Sweden)

    Yariana Martínez Sánchez

    2010-02-01

    Full Text Available Las anomalías del árbol vascular son comunes. Los aneurismas aislados de las arterias ilíacas son de observación bastante rara. Representan un porcentaje escaso de las distintas estadísticas y a menudo se resalta su aislamiento, precisamente para recordar su rareza. Reportamos un caso masculino, de 74 años de edad, que asistió a consulta por presentar síntomas urinarios. Se le realizó un ultrasonido de abdomen, observándose hidronefrosis renal bilateral moderada, además masas complejas una en cada fosa ilíaca. Se le indicó Tomografía Axial Computarizada de abdomen, donde se confirmó la hidronefrosis renal bilateral y aneurismas de ambas arterias ilíacas. Se completó el estudio con un Angiotac, y se demostró que ambas ilíacas estaban tortuosas y dilatadas (DOLICOMEGARTERIAS.Vascular tree anomalies are common. Iliac arteries isolated aneurisms are very unusual. They represent an scarce percent of the different statistics and their isolation is frequently highlighted, precisely to recollect their rareness.We report the case of a male, 74-years-old patient, assisting the consultation with urinary symptoms. An abdominal ultrasound was made, showing moderated bilateral renal hydronephrosis and also complex masses in each iliac fosse. An abdomen computed axial tomography was indicated, confirming the bilateral renal hydronephrosis and aneurisms in both iliac arteries. The study was completed with an Angiotac and it was demonstrated that both iliac arteries were tortuous and dilated ( Mega-dolicho arteries .

  2. [Paediatric retinal detachment and hereditary vitreoretinal disorders].

    Science.gov (United States)

    Meier, P

    2013-09-01

    The number of retinal detachments in children is very low in comparison to the number in adults. One predisposing factor for development of paediatric retinal detachment is suffering from hereditary vitreoretinal degeneration (e.g., Stickler syndrome, Wagner syndrome, Kniest dysplasia, familial exudative vitreoretinopathy, congenital X-linked retinoschisis, Knobloch syndrome, incontinentia pigmenti, Norrie disease). Hereditary vitreoretinopathies are characterised by an abnormal-appearing vitreous gel with associated retinal changes. In most of these eyes further ocular abnormalities can be diagnosed. A group of hereditary disorders is associated with characteristic systemic abnormalities. Allied conditions should be considered in the clinical diagnosis. Vitreoretinopathies are the most common cause of inherited retinal detachment. In most eyes primary vitrectomy is necessary, and disease-specific surgical treatment is discussed. PMID:23986190

  3. Regulatory and Economic Considerations of Retinal Drugs.

    Science.gov (United States)

    Shah, Ankoor R; Williams, George A

    2016-01-01

    The advent of anti-VEGF therapy for neovascular age-related macular degeneration and macular edema secondary to retinal vein occlusion and diabetes mellitus has prevented blindness in tens of thousands of people. However, the costs of these drugs are without precedent in ophthalmic drug therapeutics. An analysis of the financial implications of retinal drugs and the impact of the Food and Drug Administration on treatment of retinal disease must include not only an evaluation of the direct costs of the drugs and the costs associated with their administration, but also the cost savings which accrue from their clinical benefit. This chapter will discuss the financial and regulatory issues associated with retinal drugs. PMID:26502165

  4. Citomegalovirus: de la primoinfección a la retinitis

    Directory of Open Access Journals (Sweden)

    Omer Rodríguez Martínez

    2014-09-01

    Full Text Available Una vez sucedida la primoinfección, el citomegalovirus se establece latente en las células mieloides progenitoras, y la reactivación viral intermitente procedente de macrófagos activados o células dendríticas es controlada por una fuerte respuesta viral específica de células CD4 y CD8. La retinitis por citomegalovirus está caracterizada por una necrosis retinal como consecuencia de efectos citopáticos virales que ocurre en pacientes en quienes la función de células T está comprometida, como resultado de trasplantes de órganos, SIDA o tratamiento inmunosupresor. El diagnóstico de retinitis por citomegalovirus puede ser confirmado por amplificación del ADN viral en muestras de humor acuoso. El tratamiento de la retinitis por citomegalovirus se basa en la actualidad en la reconstitución del sistema inmune con la terapia TARGA y combinado a una terapia anticitomegalovirus (ganciclovir, foscarnet, cidofovir y valganciclovir. El citomegalovirus está también implicado en dos formas de enfermedad del segmento anterior en adultos inmunocompetentes llamado uveítis anterior por citomegalovirus y queratitis endotelial por citomegalovirus.

  5. Patterns of retinal damage facilitate differential diagnosis between Susac syndrome and MS.

    Science.gov (United States)

    Brandt, Alexander U; Zimmermann, Hanna; Kaufhold, Falko; Promesberger, Julia; Schippling, Sven; Finis, David; Aktas, Orhan; Geis, Christian; Ringelstein, Marius; Ringelstein, E Bernd; Hartung, Hans-Peter; Paul, Friedemann; Kleffner, Ilka; Dörr, Jan

    2012-01-01

    Susac syndrome, a rare but probably underdiagnosed combination of encephalopathy, hearing loss, and visual deficits due to branch retinal artery occlusion of unknown aetiology has to be considered as differential diagnosis in various conditions. Particularly, differentiation from multiple sclerosis is often challenging since both clinical presentation and diagnostic findings may overlap. Optical coherence tomography is a powerful and easy to perform diagnostic tool to analyse the morphological integrity of retinal structures and is increasingly established to depict characteristic patterns of retinal pathology in multiple sclerosis. Against this background we hypothesised that differential patterns of retinal pathology facilitate a reliable differentiation between Susac syndrome and multiple sclerosis. In this multicenter cross-sectional observational study optical coherence tomography was performed in nine patients with a definite diagnosis of Susac syndrome. Data were compared with age-, sex-, and disease duration-matched relapsing remitting multiple sclerosis patients with and without a history of optic neuritis, and with healthy controls. Using generalised estimating equation models, Susac patients showed a significant reduction in either or both retinal nerve fibre layer thickness and total macular volume in comparison to both healthy controls and relapsing remitting multiple sclerosis patients. However, in contrast to the multiple sclerosis patients this reduction was not distributed over the entire scanning area but showed a distinct sectorial loss especially in the macular measurements. We therefore conclude that patients with Susac syndrome show distinct abnormalities in optical coherence tomography in comparison to multiple sclerosis patients. These findings recommend optical coherence tomography as a promising tool for differentiating Susac syndrome from MS. PMID:22701702

  6. Computational model of retinal photocoagulation and rupture

    Science.gov (United States)

    Sramek, Christopher; Paulus, Yannis M.; Nomoto, Hiroyuki; Huie, Phil; Palanker, Daniel

    2009-02-01

    In patterned scanning laser photocoagulation, shorter duration (computational model of retinal photocoagulation and rupture. Model parameters were adjusted to match measured thresholds of vaporization, coagulation, and retinal pigment epithelial (RPE) damage. Computed lesion width agreed with histological measurements in a wide range of pulse durations and power. Application of ring-shaped beam profile was predicted to double the therapeutic window width for exposures in the range of 1 - 10 ms.

  7. Molecular biology of retinal ganglion cells.

    OpenAIRE

    Xiang, M; Zhou, H; Nathans, J

    1996-01-01

    Retinal ganglion cells are the output neurons that encode and transmit information from the eye to the brain. Their diverse physiologic and anatomic properties have been intensively studied and appear to account well for a number of psychophysical phenomena such as lateral inhibition and chromatic opponency. In this paper, we summarize our current view of retinal ganglion cell properties and pose a number of questions regarding underlying molecular mechanisms. As an example of one approach to...

  8. Retinal differentiation of pluripotent stem cells

    OpenAIRE

    Sarkar, Debarchana.

    2013-01-01

    The retina is an internal photosensitive neural tunic which absorbs light and prevents it from reflecting back. The light receptors and neurons of the retina are initial processor of visual information. Various anomalies of the retina such as retinitis pigmentosa, cone-rod dystrophy to retinal degenerative diseases cause severe loss of vision since they affect photoreceptors directly or indirectly. Conventional therapies have never been fully successful in restoring vision in such diseases. ...

  9. Current surgery of retinal detachment recurrence. Review

    Directory of Open Access Journals (Sweden)

    V. D. Zakharov

    2014-07-01

    Full Text Available this review presents a detailed analysis and an experience of surgical treatment of retinal detachment recurrence associated with light silicone oil tamponade of vitreous cavity. Approaches and variants of treatment were described in the historical aspect and till now. there are considered general and particular issues in case of retinal detachment recurrence appearance, expediency and volume of intraoperative manipulations, time of operation and choice of temporary substitute of vitreous body for a purpose of postoperative tamponade of vitreous cavity.

  10. Retinal iron homeostasis in health and disease

    OpenAIRE

    DeluSong; JoshuaL.Dunaief

    2013-01-01

    Iron is essential for life, but excess iron can be toxic. As a potent free radical creator, iron generates hydroxyl radicals leading to significant oxidative stress. Since iron is not excreted from the body, it accumulates with age in tissues, including the retina, predisposing to age-related oxidative insult. Both hereditary and acquired retinal diseases are associated with increased iron levels. For example, retinal degenerations have been found in hereditary iron overload disorders, like a...

  11. Retinal blood flow in diabetic retinopathy.

    OpenAIRE

    Patel, V.; RASSAM;, S.; Newsom, R.; Wiek, J; Kohner, E

    1992-01-01

    OBJECTIVES--(a) To report on the basic parameters of retinal blood flow in a population of diabetic patients with and without retinopathy and non-diabetic controls; (b) to formulate a haemodynamic model for the pathogenesis of diabetic retinopathy from this and other studies. DESIGN--Laser-Doppler velocimetry and computerised image analysis to determine retinal blood flow in a large cross sectional study. SETTING--Diabetic retinopathy outpatient clinic. SUBJECTS--24 non-diabetic controls and ...

  12. Effects of aging in retinal image quality

    OpenAIRE

    Artal, Pablo; Ferro, Manuel; Miranda, Ismael; Navarro, Rafael

    1993-01-01

    The retinal image quality characterized by the modulation-transfer function of the eye was measured for two groups of subjects aged in the late twenties and mid sixties, respectively. In both groups, we obtained modulation transfer functions by using a double-pass method under the same experimental conditions: 4-mm artificial pupil, paralyzed accommodation, and objective control of the refractive state and centering. Results showed lower values of modulation in the retinal image for older sub...

  13. Retinal dopamine and form-deprivation myopia.

    OpenAIRE

    Stone, R A; T.; Lin; Laties, A M; Iuvone, P.M.

    1989-01-01

    Investigation of retinal neurochemistry in a well-defined chick model of form-deprivation myopia indicated that dopamine and its metabolite 3,4-dihydroxyphenylacetic acid are reduced in myopic as compared to control eyes. The reduction in retinal dopamine is evident only during light adaptation and is accompanied by a decreased rate of dopamine biosynthesis. To test whether the alteration in dopamine metabolism is related to eye growth, agents known to interact with dopamine receptors were ad...

  14. Retinal iron homeostasis in health and disease

    Directory of Open Access Journals (Sweden)

    Delu Song

    2013-06-01

    Full Text Available Iron is essential for life, but excess iron can be toxic. As a potent free radical creator, iron generates hydroxyl radicals leading to significant oxidative stress. Since iron is not excreted from the body, it accumulates with age in tissues, including the retina, predisposing to age-related oxidative insult. Both hereditary and acquired retinal diseases are associated with increased iron levels. For example, retinal degenerations have been found in hereditary iron overload disorders, like aceruloplasminemia, Friedreich’s ataxia, and pantothenate kinase-associated neurodegeneration. Similarly, mice with targeted mutation of the iron exporter ceruloplasmin and its homolog hephaestin showed age-related retinal iron accumulation and retinal degeneration with features resembling human age-related macular degeneration (AMD. Post mortem AMD eyes have increased levels of iron in retina compared to age-matched healthy donors. Iron accumulation in AMD is likely to result, in part, from inflammation, hypoxia, and oxidative stress, all of which can cause iron dysregulation. Fortunately, it has been demonstrated by in vitro and in vivo studies that iron in the retinal pigment epithelium and retina is chelatable. Iron chelation protects photoreceptors and retinal pigment epithelial cells (RPE in a variety of mouse models. This has therapeutic potential for diminishing iron-induced oxidative damage to prevent or treat AMD.

  15. Isolated iliac artery aneurysms

    DEFF Research Database (Denmark)

    Levi, N; Schroeder, T V

    1998-01-01

    To assess our experience with isolated iliac artery aneurysms and to assess the blood transfusion requirement in patients undergoing surgery for iliac artery aneurysms.......To assess our experience with isolated iliac artery aneurysms and to assess the blood transfusion requirement in patients undergoing surgery for iliac artery aneurysms....

  16. Hepatic artery aneurysm.

    OpenAIRE

    Curran, F T; Taylor, S. A.

    1986-01-01

    We describe a 58 year old woman who had an aneurysm involving the common hepatic artery, the right and left hepatic arteries and the cystic artery which had ruptured into the liver. It was successfully treated by proximal ligation. The features and management of hepatic artery aneurysm are discussed.

  17. Pars plana vitrectomy for rhegmatogenous retinal detachment associated with benign retinal tumors.

    Science.gov (United States)

    Say, Emil Anthony T; Jani, Pooja D; Ulrich, J Niklas

    2013-01-01

    Two patients with known histories of benign retinal tumors presented with rhegmatogenous retinal detachments (RRD) in the same eye. One had a retinocytoma and presenting vision of 20/50, while the other had congenital hypertrophy of the retinal pigment epithelium and vision of 20/30. Both had subretinal fluid accumulation in a configuration consistent with a retinal break near the tumor; however, no breaks were detected on examination or intraoperatively. Pars plana vitrectomy (PPV), drainage retinotomy, fluid-air exchange, barrier laser around the tumor, and gas tamponade successfully reattached the retina in both cases. After 12 and 6 months of follow-up, respectively, final vision was 20/25 and the retina remained attached. RRD may be associated with benign retinal tumors presumably with microscopic breaks at the margins. In these cases, PPV, drainage retinotomy, fluid-air exchange, endolaser around the tumor, and gas tamponade can be effective for treatment. PMID:23883537

  18. Regulation of Taurine transporter activity in cultured rat retinal ganglion cells and rat retinal Muller Cells

    International Nuclear Information System (INIS)

    Diabetic retinopathy is one of the most common complications of diabetes. The amino acid taurine is believed to play an antioxidant protective role in diabetic retinopathy through the scavenging of the reactive species. It is not well established whether taurine uptake is altered in retina cells during diabetic conditions. Thus, the present study was designed to investigate the changes in taurine transport in cultures of rat retinal Muller cells and rat retinal ganglion cells under conditions associated with diabetes. Taurine was abundantly taken up by retinal Muller cells and rat retinal ganglion cells under normal glycemic condition. Taurine was actively transported to rat Muller cells and rat retinal ganglion cells in a Na and Cl dependant manner. Taurine uptake further significantly elevated in both type of cells after the incubation with high glucose concentration. This effect could be attributed to the increase in osmolarity. Because Nitric Oxide (NO) is a molecule implicated in the pathogenesis of diabetes, we also determined the activity of taurine transporter in cultured rat retinal Muller cells and rat retinal ganglion cells in the presence of the NO donors, SIN-1 and SNAP. Taurine uptake was elevated above control value after 24-h incubation with low concentration of NO donors. We finally investigated the ability of neurotoxic glutamate to change taurine transporter activity in both types of cells. Uptake of taurine was significantly increased in rat retinal ganglion cells when only incubated with high concentration of glutamate. Our data provide evidence that taurine transporter is present in cultured rat retinal ganglion and Muller cells and is regulated by hyperosmolarity. The data are relevant to disease such as diabetes and neuronal degeneration where retinal cell volume may dramatically change. (author)

  19. Rhegmatogenous retinal detachment: current opinion

    Directory of Open Access Journals (Sweden)

    T. A. Avanesova

    2015-03-01

    Full Text Available Rhegmatogenous retinal detachment (RRD is a severe ocular disorder which requires prompt treatment to prevent low vision and blindness. It is also a significant socio-economic problem as 84% of RDD patients are able-bodied. RRD grading systems (including current Machemer grading system, risk factors, and pathogenesis are reviewed. The role of proliferative vitreoretinopathy in RDD pathogenesis and recurrence is described. Macula involvement determines RDD outcome. Optical coherence tomography (OCT provides the study of retina anatomy and the analysis of parameters that affect post-op best corrected visual acuity, i.e., defects of the junction between inner segments and outer segments (IS/OS, the integrity of external (ELM and internal limiting membrane (ILM, outer nuclear layer thickness (ONLT etc. Fluorescent angiography allows to understand the reasons for low vision in anatomically successful RDD surgery. Scleral buckling, balloon buckling, pneumatic retinopexy, vitrectomy, cryopexy, and laser coagulation are important tools in surgical armamentarium. In recent years, vitrectomy is growing in popularity for RDD treatment. Criteria for procedure selection and surgical success rate in phakic and pseudophakic eyes are discussed. The outcomes of vitrectomy with air/gas and silicone oil tamponade are compared. Bimanual vitrectomy benefits are discussed. 

  20. Management of pseudoaneurysms in the intracranial segment of the internal carotid artery with covered stents specially designed for use in the intracranial vasculature: technical notes

    International Nuclear Information System (INIS)

    Vascular diseases like aneurysms, pseudoaneurysms and direct high-flow carotid-cavernous fistulas on the intracranial segment of the internal carotid artery are usually managed through transarterial embolization with detachable coils or balloons. Utility of covered stents has been reported with good results in the treatment of selective cases. But the current generation of covered stents for coronary use is rather stiff and difficult to navigate in tortuous vessels particularly in the intracranial vasculature. Herein, we report on the use and technical respects of balloon-expanded covered stents specially designed for intracranial vasculature in the treatment of two pseudoaneurysms secondary to the successful obliteration of direct CCFs on the intracranial segment of the internal carotid artery. This is the first report of covered stents specially developed for use in intracranial vasculature. (orig.)

  1. Changes in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure in men and women with primary open angle glaucoma

    Directory of Open Access Journals (Sweden)

    Marjanovi? Ivan

    2013-01-01

    Full Text Available Introduction. An altered perfusion of the optic nerve head has been proposed as a pathogenic factor of glaucoma. Objective. The aim of this study was to evaluate the changes of the hemodynamic parameters in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure (IOP in women and men with primary open angle glaucoma. Methods. The study included 60 patients (33 males and 27 females older than 50 years, with diagnosed and treated primary open angle glaucoma (77 eyes of 39 patients had increased IOP, >25 mm Hg. They were examined at the Clinic of Eye Diseases (complete ophthalmologic exam and Clinic of Neurology, Clinical Center of Serbia, Belgrade, from December 2009 to December 2010. Imaging of hemodynamic parameters of three retrobulbar arterial vessels: ophthalmic, central retinal and posterior ciliary arteries with color Doppler was performed. Results. Among women, hemodynamic arterial parameter of the peak-systolic velocity was increased in the central retinal artery and decreased in the ophthalmic artery and posterior ciliary arteries; end- diastolic velocity was increased in all three retrobulbar vascular levels; Pourcelot resistivity index was increased, but pulsatility index was decreased in all three vessels. Among men, peak-systolic velocity, end-diastolic velocity and pulsatility index were decreased in all three vessels; resistivity index was increased in the ophthalmic artery, but decreased in the central retinal artery and posterior ciliary arteries. There was a significant change of the ophthalmic artery pulsatility index in women, and the end-diastolic velocity of the ophthalmic artery in men. Conclusion. There was a difference of the retrobulbar arterial circulation between women and men with primary open angle glaucoma after decrease of the elevated intraocular pressure. The role of vascular factors in the supply of the optic disc neuroretinal rim is important.

  2. Melanopsin retinal ganglion cell loss in Alzheimer's disease

    DEFF Research Database (Denmark)

    La Morgia, Chiara; Ross-Cisneros, Fred N; Koronyo, Yosef; Hannibal, Jens; Gallassi, Roberto; Cantalupo, Gaetano; Sambati, Luisa; Pan, Billy X; Tozer, Kevin R; Barboni, Piero; Provini, Federica; Avanzini, Pietro; Carbonelli, Michele; Pelosi, Annalisa; Chui, Helena; Liguori, Rocco; Baruzzi, Agostino; Koronyo-Hamaoui, Maya; Sadun, Alfredo A; Carelli, Valerio

    2015-01-01

    OBJECTIVE: Melanopsin retinal ganglion cells (mRGCs) are photoreceptors driving circadian photoentrainment, and circadian dysfunction characterizes Alzheimer's disease (AD). We investigated mRGCs in AD, hypothesizing their contribution to circadian dysfunction. METHODS: We assessed retinal nerve...

  3. Neoplasia versus hyperplasia of the retinal pigment epithelium

    DEFF Research Database (Denmark)

    Heegaard, Steffen; Larsen, J.N.B.; Fledelius, Hans C.; Prause, J.U.

    ophthalmology, retinal pigment epithelium, adenoma, tumor-like hyperplasia, histology, immunohistochemistry, tumor, neoplasm, ultrasonography......ophthalmology, retinal pigment epithelium, adenoma, tumor-like hyperplasia, histology, immunohistochemistry, tumor, neoplasm, ultrasonography...

  4. Evaluation and management of pediatric rhegmatogenous retinal detachment.

    Science.gov (United States)

    Wenick, Adam S; Barañano, David E

    2012-07-01

    Pediatric rhegmatogenous retinal detachments are rare, accounting for less than ten percent of all rhegmatogenous retinal detachments. While most retinal detachments in the adult population are related to posterior vitreous detachment, pediatric retinal detachment are often related to trauma or an underlying congenital abnormalities or genetic syndrome. The anatomy of pediatric eyes, the often late presentation of the disease, and the high incidence of bilateral pathology in children all pose significant challenges in the management of these patients. We discuss the epidemiology of pediatric rhegmatogenous retinal detachment, review the genetic syndromes associated with a high incidence of retinal detachment, and examine other common causes of retinal detachment in this age group. We then outline an approach to evaluation and management and describe the expected outcomes of repair of retinal detachment in the pediatric population. PMID:23961003

  5. Genetics Home Reference: Neuropathy, ataxia, and retinitis pigmentosa

    Science.gov (United States)

    ... OMIM Genetic disorder catalog Conditions > Neuropathy, ataxia, and retinitis pigmentosa (often shortened to NARP ) On this page: Description ... November 2006 What is NARP? Neuropathy, ataxia, and retinitis pigmentosa (NARP) is a condition that causes a variety ...

  6. Genetics Home Reference: Neuropathy, ataxia, and retinitis pigmentosa

    Science.gov (United States)

    ... Recent literature OMIM Genetic disorder catalog Conditions > Neuropathy, ataxia, and retinitis pigmentosa (often shortened to NARP ) On ... definitions Reviewed November 2006 What is NARP? Neuropathy, ataxia, and retinitis pigmentosa (NARP) is a condition that ...

  7. Retinal imaging with virtual reality stimulus for studying Salticidae retinas

    Science.gov (United States)

    Schiesser, Eric; Canavesi, Cristina; Long, Skye; Jakob, Elizabeth; Rolland, Jannick P.

    2014-12-01

    We present a 3-path optical system for studying the retinal movement of jumping spiders: a visible OLED virtual reality system presents stimulus, while NIR illumination and imaging systems observe retinal movement.

  8. Retinal Function and Structure in Ant1-Deficient Mice

    OpenAIRE

    Phillips, M. Joseph; Webb-Wood, Sarah; Faulkner, Amanda E.; Jabbar, Seema B.; BIOUSSE, VALERIE; Newman, Nancy J.; Do, Vi T.; Boatright, Jeffrey H.; Wallace, Douglas C; Pardue, Machelle T

    2010-01-01

    Because the retina has high energy demands, the loss of a mitochondrial ATP transporter was predicted to impact retinal function. The authors examined retinal function and morphology in mice without ANT1, a key ATP transporter associated with myopathy.

  9. MR detection of retinal hemorrhages: correlation with graded ophthalmologic exam

    Energy Technology Data Exchange (ETDEWEB)

    Beavers, Angela J.; Allbery, Sandra M. [University of Nebraska Medical Center, Department of Radiology, Omaha, NE (United States); Children' s Hospital and Medical Center, Department of Radiology, Omaha, NE (United States); Stagner, Anna M.; Hejkal, Thomas W. [University of Nebraska Medical Center, Department of Ophthalmology, Omaha, NE (United States); Children' s Hospital and Medical Center, Department of Ophthalmology, Omaha, NE (United States); Lyden, Elizabeth R. [University of Nebraska Medical Center, College of Public Health, Omaha, NE (United States); Haney, Suzanne B. [Children' s Hospital and Medical Center, Department of Pediatrics, Omaha, NE (United States); University of Nebraska Medical Center, Department of Pediatrics, Omaha, NE (United States)

    2015-08-15

    Dilated fundoscopic exam is considered the gold standard for detecting retinal hemorrhage, but expertise in obtaining this exam is not always immediately available. MRI can detect retinal hemorrhages, but correlation of the grade or severity of retinal hemorrhage on dilated fundoscopic exam with retinal hemorrhage visibility on MRI has not been described. To determine the value of standard brain protocol MRI in detecting retinal hemorrhage and to determine whether there is any correlation with MR detection of retinal hemorrhage and the dilated fundoscopic exam grade of hemorrhage. We conducted a retrospective chart review of 77 children <2 years old who were seen for head trauma from April 2007 to July 2013 and had both brain MRI and dilated fundoscopic exam or retinal camera images. A staff pediatric radiologist and radiology resident reviewed the MR images. Retinal hemorrhages were graded by a chief ophthalmology resident on a 12-point scale based on the retinal hemorrhage type, size, location and extent as seen on review of retinal camera images and detailed reports by ophthalmologists. Higher scores indicated increased severity of retinal hemorrhages. There was a statistically significant difference in the median grade of retinal hemorrhage examination between children who had retinal hemorrhage detected on MRI and children who did not have retinal hemorrhage detected on MRI (P = 0.02). When examination grade was categorized as low-grade (1-4), moderate-grade (5-8) or high-grade (>8) hemorrhage, there was a statistically significant association between exam grade and diagnosis based on MRI (P = 0.008). For example, only 14% of children with low-grade retinal hemorrhages were identified on MRI compared to 76% of children with high-grade hemorrhages. MR detection of retinal hemorrhage demonstrated a sensitivity of 61%, specificity of 100%, positive predictive value of 100% and negative predictive value of 63%. Retinal hemorrhage was best seen on the gradient recalled echo (GRE) sequences. MRI using routine brain protocol demonstrated 61% sensitivity and 100% specificity in detecting retinal hemorrhage. High-grade hemorrhage was more often detected on MRI than low-grade hemorrhage, 76% vs. 14%. GRE images were the most sensitive for detection of retinal hemorrhages. A dilated fundoscopic exam can be difficult to obtain in infancy, especially in critically ill or non-sedated children. MRI is a useful modality for added documentation of retinal hemorrhage and can be used as an alternative exam when ophthalmologic expertise or retinal camera images are unavailable. Additionally, identification of retinal hemorrhage on MRI can raise the possibility of abuse in children presenting with nonspecific findings. (orig.)

  10. MR detection of retinal hemorrhages: correlation with graded ophthalmologic exam

    International Nuclear Information System (INIS)

    Dilated fundoscopic exam is considered the gold standard for detecting retinal hemorrhage, but expertise in obtaining this exam is not always immediately available. MRI can detect retinal hemorrhages, but correlation of the grade or severity of retinal hemorrhage on dilated fundoscopic exam with retinal hemorrhage visibility on MRI has not been described. To determine the value of standard brain protocol MRI in detecting retinal hemorrhage and to determine whether there is any correlation with MR detection of retinal hemorrhage and the dilated fundoscopic exam grade of hemorrhage. We conducted a retrospective chart review of 77 children <2 years old who were seen for head trauma from April 2007 to July 2013 and had both brain MRI and dilated fundoscopic exam or retinal camera images. A staff pediatric radiologist and radiology resident reviewed the MR images. Retinal hemorrhages were graded by a chief ophthalmology resident on a 12-point scale based on the retinal hemorrhage type, size, location and extent as seen on review of retinal camera images and detailed reports by ophthalmologists. Higher scores indicated increased severity of retinal hemorrhages. There was a statistically significant difference in the median grade of retinal hemorrhage examination between children who had retinal hemorrhage detected on MRI and children who did not have retinal hemorrhage detected on MRI (P = 0.02). When examination grade was categorized as low-grade (1-4), moderate-grade (5-8) or high-grade (>8) hemorrhage, there was a statistically significant association between exam grade and diagnosis based on MRI (P = 0.008). For example, only 14% of children with low-grade retinal hemorrhages were identified on MRI compared to 76% of children with high-grade hemorrhages. MR detection of retinal hemorrhage demonstrated a sensitivity of 61%, specificity of 100%, positive predictive value of 100% and negative predictive value of 63%. Retinal hemorrhage was best seen on the gradient recalled echo (GRE) sequences. MRI using routine brain protocol demonstrated 61% sensitivity and 100% specificity in detecting retinal hemorrhage. High-grade hemorrhage was more often detected on MRI than low-grade hemorrhage, 76% vs. 14%. GRE images were the most sensitive for detection of retinal hemorrhages. A dilated fundoscopic exam can be difficult to obtain in infancy, especially in critically ill or non-sedated children. MRI is a useful modality for added documentation of retinal hemorrhage and can be used as an alternative exam when ophthalmologic expertise or retinal camera images are unavailable. Additionally, identification of retinal hemorrhage on MRI can raise the possibility of abuse in children presenting with nonspecific findings. (orig.)

  11. Optimal management of cytomegalovirus retinitis in patients with AIDS

    OpenAIRE

    Stewart, Michael W.

    2010-01-01

    Michael W StewartDepartment of Ophthalmology, Mayo School of Medicine, Jacksonville, FL, USAAbstract: Cytomegalovirus (CMV) retinitis is the most common cause of vision loss in patients with acquired immunodeficiency syndrome (AIDS). CMV retinitis afflicted 25% to 42% of AIDS patients in the pre-highly active antiretroviral therapy (HAART) era, with most vision loss due to macula-involving retinitis or retinal detachment. The introduction of HAART significantly decreased the incidence and sev...

  12. Evaluation and management of pediatric rhegmatogenous retinal detachment

    OpenAIRE

    Wenick, Adam S.; Barañano, David E.

    2012-01-01

    Pediatric rhegmatogenous retinal detachments are rare, accounting for less than ten percent of all rhegmatogenous retinal detachments. While most retinal detachments in the adult population are related to posterior vitreous detachment, pediatric retinal detachment are often related to trauma or an underlying congenital abnormalities or genetic syndrome. The anatomy of pediatric eyes, the often late presentation of the disease, and the high incidence of bilateral pathology in children all pose...

  13. Retinal detachment in Scotland is associated with affluence

    OpenAIRE

    Saidkasimova, S; Mitry, D; Singh, J.; YORSTON, D.; Charteris, D G

    2009-01-01

    Abstract Aim. Socio-economic deprivation plays a major role in health and disease, however its role in retinal detachment has not been studied. We used data from the Scottish Retinal Detachment Study to investigate any association between retinal detachment, macular status at presentation, and deprivation,. Methods. Prospective multicentre population based observational study. Data was collected on all patients with primary retinal detachment presenting in Scotland between 1 Nov...

  14. Potential for Autoimmune Pathogenesis of Rift Valley Fever Virus Retinitis

    OpenAIRE

    Newman-Gerhardt, Shoshana; Muiruri, Samuel; MUCHIRI, ERIC; Peters, Clarence J; Morrill, John; Lucas, Alexander H.; KING, CHARLES H.; Kazura, James; LaBeaud, Angelle Desiree

    2013-01-01

    Rift Valley Fever (RVF) is a significant threat to human health because it can progress to retinitis, encephalitis, and hemorrhagic fever. The timing of onset of Rift Valley Fever virus (RVFV) retinitis suggests an autoimmune origin. To determine whether RVFV retinitis is associated with increased levels of IgG against retinal tissue, we measured and compared levels of IgG against healthy human eye tissue by immunohistochemical analysis. We found that serum samples from RVFV-exposed Kenyans w...

  15. Retinal Transplants: Growth Differentiation Integration Organization and Survival

    OpenAIRE

    Sharma, Rajesh Kumar

    1999-01-01

    The goal of the study was to get a better understanding of factors controlling the growth, differen-tia-tion, integration, organization and survival of retinal transplants, with the long-term view of eventually developing retinal transplantation into a clinically useful procedure for treating degenerative retinal disorders such as retinitis pigmentosa. Embryonic day 15 rabbit retinas were transplanted into adult rabbit eyes and were allowed to survive for various times. Aspects of grow...

  16. Stainless steel micro needle for retinal vein cannulation

    OpenAIRE

    Willekens, Koen; Gijbels, Andy; Vander Poorten, Emmanuel; Reynaerts, Dominiek; Stalmans, Peter

    2015-01-01

    Purpose: The current management of retinal vein occlusion consists mainly of treating its complications instead of the The current management of retinal vein occlusion consists mainly of treating its complications instead of the cause. Although successful blood clot removal via retinal vein cannulation using glass micropipettes has been reported, cause. Although successful blood clot removal via retinal vein cannulation using glass micropipettes has been reported, such glass design is frag...

  17. Treatment of CMV retinitis in an AIDS patient.

    OpenAIRE

    Acheson, J F; Shah, S. M.; Spalton, D J; Bradbeer, C.; Thin, R. N.

    1987-01-01

    We present a case of cytomegalovirus (CMV) retinitis in an AIDS patient who survived for 10 months after the start of his ocular problems. The retinitis responded to dihydroxy propoxy methyl guanine (DHPG) but relapsed four to six weeks after each course of treatment with progressive retinal destruction. One relapse was therefore treated with trisodium phosphoformate hexahydrate (Foscarnet). There are few reports of the use of this drug in the treatment of CMV retinitis with AIDS, but it appe...

  18. Retinal image analysis using multidirectional functors based on geodesic conversions

    OpenAIRE

    SHAHBEIG, Saleh

    2014-01-01

    A retinal image contains vital information. Extracting these features is the first and most important step in the analysis of retinal images for various applications of medical or human recognition. In this study, a morphological-based blood vessel extraction algorithm using adaptive-local analysis from colored retinal images is proposed. In this algorithm, by applying the appropriate morphology functors and local histogram stretching on the retinal images, the brightness of the images ...

  19. Performance Analysis of Retinal Image Blood Vessel Segmentation

    OpenAIRE

    Siva Sundhara Raja, D.; Dr.S.Vasuki; D.Rajesh Kumar

    2014-01-01

    The retinal image diagnosis is an important methodology for diabetic retinopathy detection and analysis. in this paper, the morphological operations and svm classifier are used to detect and segment the blood vessels from the retinal image. the proposed system consists of three stages-first is preprocessing of retinal image to separate the green channel and second stage is retinal image enhancement and third stage is blood vessel segmentation using morphological operations and svm classifier....

  20. Retinal image registration and comparison for clinical decision support

    OpenAIRE

    Di Xiao; Janardhan Vignarajan; Jane Lock; Shaun Frost; Mei-Ling Tay-Kearney; Yogesan Kanagasingam

    2012-01-01

    Background For eye diseases, such as glaucoma and age-related macular degeneration (ARMD), involved in long-term degeneration procedure, longitudinal comparison of retinal images is a common step for reliable diagnosis of these kinds of diseases. Aims To provide a retinal image registration approach for longitudinal retinal image alignment and comparison. Method Two image registration solutions were proposed for facing different image qualities of retinal images to make the registration metho...

  1. Detection of Retinal Hemorrhage Using Splat Feature Classification Technique

    OpenAIRE

    Athira R V,; Ferlin Deva Shahila D

    2014-01-01

    In the automated fundus image screening system, reliable detection of retinal hemorrhage is required. Retinal hemorrhages are produced by diabetic retinopathy and hypertension. In our approach, a splat feature classification technique can be used to detect large irregular retinal hemorrhages with high accuracy. In this technique, the retinal images are partitioned into non overlapping segments called splat. Splat contains pixels with same color and spatial location. From each ...

  2. Minimizing the influence of fundus pigmentation on retinal vessel oximetry measurements

    Science.gov (United States)

    Smith, Matthew H.; Denninghoff, Kurt R.; Lompado, Arthur; Woodruff, Jacob B.; Hillman, Lloyd W.

    2001-06-01

    The goal of making calibrated oxygen saturation measurements of blood in retinal arteries and veins via a noninvasive spectroscopic technique has nearly been realized. Semi-continuous advancement in the field of retinal vessel oximetry over the last three decades has resulted in several technologies that seem poised for commercialization. In this paper, we present our instrumentation and technique for making well-calibrated saturation measurements of the blood in retinal vessels. The Eye Oximeter (EOX) is a confocal scanning laser ophthalmoscope capable of acquiring multi-spectral images. Analysis of these spectral vessel images allows spectroscopic determination of the oxygen saturation of blood within each vessel. The primary emphasis of this paper is to illustrate the effect of fundus pigmentation on these oximetric measurements. We show that decreasing fundus reflectivity is mathematically similar to decreasing the vessel thickness. The apparent decreased vessel thickness is a direct consequence of scattering by red blood cells. We present in vitro and in vivo measurements that demonstrate an instrument calibration that is nearly independent of vessel diameter and fundus reflectivity.

  3. Dissecting aneurysm of the cervical internal carotid artery

    International Nuclear Information System (INIS)

    On lifting a heavy case, a 51-year-old male experienced a sudden onset of headache with giddiness and clouded vision. A week later, vertigo and right hand numbness were added to his symptoms. The next day anisocoria (right > left) and dilation of the left retinal veins were noted. Cranial computed tomography (CT) scan appeared normal and there were no other remarkable neurological findings. The patient was treated conservatively for cerebral infarction, however, the headache worsened and diplopia occurred. Neurological examination on admission revealed nothing unusual except for left Horner's syndrome. Physical examination showed a palpable sausage-like painless tumor on the left side of the neck. Angiography showed a narrowing of the internal carotid artery in the cervical region with a small dissecting aneurysm at the C3 level. Cervical CT scan at the upper C3 level showed a low density lunar defect in the high density section of the enlarged left internal carotid artery. The patient was operated on by superficial temporal artery-middle cerebral artery anastomosis to increase the intracranial blood flow. Postoperatively the symptoms were quickly relieved. Angiography 1 month later showed less narrowing of the carotid artery, though the dissecting aneurysm still remained. Postoperative cervical CT scan showed the left internal carotid artery to be of normal size. The patient returned to his work in normal condition 2 months later. It is emphasized that cervical CT scan may be useful in the diagnosis of this unusual type of cervical dissecting aneurysm. (author)

  4. Enhanced generation of retinal progenitor cells from human retinal pigment epithelial cells induced by amniotic fluid

    Directory of Open Access Journals (Sweden)

    Sanie-Jahromi Fatemeh

    2012-04-01

    Full Text Available Abstract Background Retinal progenitor cells are a convenient source of cell replacement therapy in retinal degenerative disorders. The purpose of this study was to evaluate the expression patterns of the homeobox genes PAX6 and CHX10 (retinal progenitor markers during treatment of human retinal pigment epithelium (RPE cells with amniotic fluid (AF, RPE cells harvested from neonatal cadaver globes were cultured in a mixture of DMEM and Ham's F12 supplemented with 10% FBS. At different passages, cells were trypsinized and co-cultured with 30% AF obtained from normal fetuses of 1416 weeks gestational age. Results Compared to FBS-treated controls, AF-treated cultures exhibited special morphological changes in culture, including appearance of spheroid colonies, improved initial cell adhesion and ordered cell alignment. Cell proliferation assays indicated a remarkable increase in the proliferation rate of RPE cells cultivated in 30% AF-supplemented medium, compared with those grown in the absence of AF. Immunocytochemical analyses exhibited nuclear localization of retinal progenitor markers at a ratio of 33% and 27% for CHX10 and PAX6, respectively. This indicated a 3-fold increase in retinal progenitor markers in AF-treated cultures compared to FBS-treated controls. Real-time PCR data of retinal progenitor genes (PAX6, CHX10 and VSX-1 confirmed these results and demonstrated AF's capacity for promoting retinal progenitor cell generation. Conclusion Taken together, the results suggest that AF significantly promotes the rate of retinal progenitor cell generation, indicating that AF can be used as an enriched supplement for serum-free media used for the in vitro propagation of human progenitor cells.

  5. Human umbilical tissue-derived cells rescue retinal pigment epithelium dysfunction in retinal degeneration.

    Science.gov (United States)

    Cao, Jing; Murat, Christopher; An, Weijun; Yao, Xiang; Lee, John; Santulli-Marotto, Sandra; Harris, Ian R; Inana, George

    2016-02-01

    Retinal pigment epithelium (RPE) cells perform many functions crucial for retinal preservation and vision. RPE cell dysfunction results in various retinal degenerative diseases, such as retinitis pigmentosa and age-related macular degeneration (AMD). Currently, there are no effective treatments for retinal degeneration except for a small percentage of individuals with exudative AMD. Cell therapies targeting RPE cells are being developed in the clinic for the treatment of retinal degeneration. Subretinal injection of human umbilical tissue-derived cells (hUTC) in the Royal College of Surgeons (RCS) rat model of retinal degeneration was shown to preserve photoreceptors and visual function. However, the precise mechanism remains unclear. Here, we demonstrate that hUTC rescue phagocytic dysfunction in RCS RPE cells in vitro. hUTC secrete receptor tyrosine kinase (RTK) ligands brain-derived neurotrophic factor (BDNF), hepatocyte growth factor (HGF), and glial cell-derived neurotrophic factor (GDNF), as well as opsonizing bridge molecules milk-fat-globule-epidermal growth factor 8 (MFG-E8), growth arrest-specific 6 (Gas6), thrombospondin (TSP)-1, and TSP-2. The effect of hUTC on phagocytosis rescue in vitro is mimicked by recombinant human proteins of these factors and is abolished by siRNA-targeted gene silencing in hUTC. The bridge molecules secreted from hUTC bind to the photoreceptor outer segments and facilitate their ingestion by the RPE. This study elucidates novel cellular mechanisms for the repair of RPE function in retinal degeneration through RTK ligands and bridge molecules, and demonstrates the potential of using hUTC for the treatment of retinal degenerative diseases. Stem Cells 2016;34:367-379. PMID:26523756

  6. Low Vision Rehabilitation of Retinitis Pigmentosa. Practice Report

    Science.gov (United States)

    Rundquist, John

    2004-01-01

    Retinitis pigmentosa is a rod-cone dystrophy, commonly genetic in nature. Approximately 60-80% of those with retinitis pigmentosa inherit it by an autosomal recessive transmission (Brilliant, 1999). There have been some reported cases with no known family history. The symptoms of retinitis pigmentosa are decreased acuity, photophobia, night…

  7. Retinal vascular and structural dynamics during acute hyperglycaemia

    DEFF Research Database (Denmark)

    Klefter, Oliver N; Vilsbøll, Tina; Knop, Filip K; Larsen, Michael

    2015-01-01

    PURPOSE: To compare retinal vascular dynamics during acute hyperglycaemia in patients with type 2 diabetes and healthy volunteers. METHODS: Twenty-one patients with type 2 diabetes and 27 healthy controls were examined with fundus photographic measurement of retinal vessel diameters, retinal oxim...

  8. Retinal Fiber Tracing by In Ovo Electroporation

    Science.gov (United States)

    Harada, Hidekiyo; Nakamura, Harukazu

    Axonal tracing techniques are the fundamentals for the investigation of neural circuit formation. In ovo electroporation system allows us to transfect a gene of interest to the desired place in chick embryos (Odani et al., 2008). Recently, Tol2 transposase element, which was originally found in medaka fish (Koga et al., 1996), has been adapted to an in ovo electroporation system (Niwa et al., 1991; Kawakami et al., 1998, 2000, 2004a, 2004b; Kawakami & Noda, 2004; Kawakami, 2005, 2007; Sato et al., 2007). This system assures the integration of the transgene into the genome by electroporation (Niwa et al., 1991; Sato et al., 2007). We applied this system for tracing retinal fibers (Harada et al., 2008). In this chapter, we demonstrate the method of tracing retinal fibers from both small and large groups of the retinal ganglion cell (RGC) with transposon-mediated gene transfer by in ovo electroporation to chick embryos.

  9. Marfan Syndrome Presenting with Bilateral Retinal Detachment

    Directory of Open Access Journals (Sweden)

    Subrata Chakrabarti

    2014-02-01

    Full Text Available Marfan syndrome is an autosomal dominant systemic disorder of the connective tissue. Marfan syndrome affects most organs and tissues, especially the skeleton, lungs, eyes, heart, and the large blood vessels. Eye involvement may be in the form of retinal detachment which is a potentially dangerous manifestation for its sight threatening nature .We report a case where a 17 year old male developed sudden blindness due to spontaneous bilateral retinal detachment. Examination revealed features of Marfan syndrome and was stamped as a case of Marfan syndrome by Ghent criteria . The point to stress upon is that a young male developing spontaneous retinal detachment, a diagnosis of underlying Marfan syndrome should be kept in mind if appropriate clinical stigmata are present. [Natl J Med Res 2014; 4(1.000: 104-105

  10. Autophagy in light-induced retinal damage.

    Science.gov (United States)

    Chen, Yu; Perusek, Lindsay; Maeda, Akiko

    2016-03-01

    Vision is reliant upon converting photon signals to electrical information which is interpreted by the brain and therefore allowing us to receive information about our surroundings. However, when exposed to excessive light, photoreceptors and other types of cells in the retina can undergo light-induced cell death, termed light-induced retinal damage. In this review, we summarize our current knowledge regarding molecular events in the retina after excessive light exposure and mechanisms of light-induced retinal damage. We also introduce works which investigate potential roles of autophagy, an essential cellular mechanism required for maintaining homeostasis under stress conditions, in the illuminated retina and animal models of light-induced retinal damage. PMID:26325327

  11. Enhancing retinal images by nonlinear registration

    CERN Document Server

    Molodij, Guillaume; Glanc, Marie; Chenegros, Guillaume

    2014-01-01

    Being able to image the human retina in high resolution opens a new era in many important fields, such as pharmacological research for retinal diseases, researches in human cognition, nervous system, metabolism and blood stream, to name a few. In this paper, we propose to share the knowledge acquired in the fields of optics and imaging in solar astrophysics in order to improve the retinal imaging at very high spatial resolution in the perspective to perform a medical diagnosis. The main purpose would be to assist health care practitioners by enhancing retinal images and detect abnormal features. We apply a nonlinear registration method using local correlation tracking to increase the field of view and follow structure evolutions using correlation techniques borrowed from solar astronomy technique expertise. Another purpose is to define the tracer of movements after analyzing local correlations to follow the proper motions of an image from one moment to another, such as changes in optical flows that would be o...

  12. The age-dependent decrease in the myogenic response of retinal arterioles as studied with the Retinal Vessel Analyzer

    DEFF Research Database (Denmark)

    Jeppesen, Peter; Gregersen, Pernille Axel; Bek, Toke

    2004-01-01

    PURPOSE: To study the age-dependent change in myogenic response of retinal arterioles. METHODS: Fifty-one healthy volunteers with at least ten persons in each of the five age decades (I-V) between 20 and 69 years were subjected to diameter measurement of retinal arterioles using the Retinal Vessel Analyzer (RVA) during rest and during an increase in the systemic blood pressure when lifting hand weights. The transmural pressure in the retinal arterioles during the procedures was estimated from th...

  13. Comparison of reflectivity maps and outer retinal topography in retinal disease by 3-D Fourier domain optical coherence tomography◊

    OpenAIRE

    Wojtkowski, Maciej; Sikorski, Bartosz L.; Gorczynska, Iwona; Gora, Michalina; Szkulmowski, Maciej; Bukowska, Danuta; Kałuzny, Jakub; Fujimoto, James G.; Kowalczyk, Andrzej

    2009-01-01

    We demonstrate and compare two image processing methods for visualization and analysis of three-dimensional optical coherence tomography (OCT) data acquired in eyes with different retinal pathologies. A method of retinal layer segmentation based on a multiple intensity thresholding algorithm was implemented in order to generate simultaneously outer retinal topography maps and reflectivity maps. We compare the applicability of the two methods to the diagnosis of retinal diseases and their prog...

  14. Multimodal Registration Procedure for the Initial Spatial Alignment of a Retinal Video Sequence to a Retinal Composite Image

    OpenAIRE

    Bröhan, A Martina; Tappeiner, Christoph; Rothenbühler, Simon P; Rudolph, Tobias; Amstutz, Christoph A; Kowal, Jens H

    2010-01-01

    Accurate placement of lesions is crucial for the effectiveness and safety of a retinal laser photocoagulation treatment. Computer assistance provides the capability for improvements to treatment accuracy and execution time. The idea is to use video frames acquired from a scanning digital ophthalmoscope (SDO) to compensate for retinal motion during laser treatment. This paper presents a method for the multimodal registration of the initial frame from an SDO retinal video sequence to a retinal ...

  15. Alterations of the blood-retinal barrier and retinal thickness in preclinical retinopathy in subjects with type 2 diabetes

    OpenAIRE

    Lobo, CL; Bernardes, RC; Cunha-Vaz, JG

    2000-01-01

    OBJECTIVE: To identify alterations of the blood-retinal barrier by mapping retinal fluorescein leakage into the vitreous and changes in retinal thickness occurring in the macular region in preclinical diabetic retinopathy. METHODS: Ten eyes from 10 patients with type 2 diabetes and no lesions visible on fundus photography (level 10 of Wisconsin grading) were examined with the retinal leakage analyzer (RLA) (Confocal Scanning Laser Ophthalmoscope [modified]; Carl Zeiss Inc, Thornwood, NY) ...

  16. Reading visual Braille with a retinal prosthesis

    Directory of Open Access Journals (Sweden)

    ThomasZaccarinLauritzen

    2012-11-01

    Full Text Available Retinal prostheses, which restore partial vision to patients blinded by outer retinal degeneration, are currently in clinical trial. The Argus II retinal prosthesis system was recently awarded CE approval for commercial use in Europe. While retinal prosthesis users have achieved remarkable visual improvement to the point of reading letters and short sentences, the reading process is still fairly cumbersome. This study investigates the possibility of using an epiretinal prosthesis to stimulate visual Braille as a sensory substitution for reading written letters and words. The Argus II retinal prosthesis system, used in this study, includes a 10 x 6 electrode array implanted epiretinally, a tiny video camera mounted on a pair of glasses, and a wearable computer that processes the video and determines the stimulation current of each electrode in real time. In the Braille reading system, individual letters are created by a subset of dots from a 3 by 2 array of six dots. For the visual Braille experiment, a grid of six electrodes was chosen out of the 10 x 6 Argus II array. Groups of these electrodes were then directly stimulated (bypassing the camera to create visual percepts of individual Braille letters. Experiments were performed in a single subject. Single letters were stimulated in an alternative forced choice (AFC paradigm, and short 2-4-letter words were stimulated (one letter at a time in an open-choice reading paradigm. The subject correctly identified 89% of single letters, 80% of 2-letter, 60% of 3-letter, and 70% of 4-letter words. This work suggests that text can successfully be stimulated and read as visual Braille in retinal prosthesis patients.

  17. Traumatic Axillary Artery Dissection with Radial Artery Embolism

    International Nuclear Information System (INIS)

    This report describes a case of pathologically proven traumatic arterial dissection, presenting as complete occlusion of the axillary artery with radial artery embolism. Occlusion of the axillary artery by traumatic dissection mimicked transection and radial artery embolism mimicked congenital absence of the radial artery on the initial angiogram, but these were correctly diagnosed with the following sonogram

  18. Noninvasive Measurement Of The Retinal Thickness

    Science.gov (United States)

    Shahidi, Mahnaz; Zeimer, Ran C.; Mori, Marek T.

    1989-12-01

    In order to diagnose certain ocular diseases such as macular edema and atrophy, and to monitor their therapy closely, an accurate measurement of the retinal thickness is essential. We have developed a method which is capable of providing a quantitative thickness profile along a 2 mm length on the retina. A preliminary evaluation of the instrument was performed in normal human subjects. With this method, the retinal thickness can be visualized in a region extending from the optic disc to the fovea and the reproducibility of the measurement was found to be 8% (32 microns).

  19. Flexible Microelectrode Arrays for Retinal Prostheses

    Directory of Open Access Journals (Sweden)

    Seung Woo Lee

    2010-04-01

    Full Text Available In this paper, we introduce novel flexible polymer-based retinal stimulation electrodes and their performance in vivo experiments. Polyimide-based 3-D electrodes were fabricated and implanted in suprachoroidal space of rabbit eyes. The implanted 3-D electrodes were observed by Optical coherence tomography (OCT; and electrically evoked cortical potentials (EECPs were recorded. Liquid Crystal Polymers (LCPs–based retinal stimulation electrodes were developed and successfully implanted in suprachoroidal space of rabbit eyes. OCT observation and EECPs recording were performed to evaluate the LCP electrodes’ biocompatibility and functionality.

  20. Retinal image analysis: preprocessing and feature extraction

    Energy Technology Data Exchange (ETDEWEB)

    Marrugo, Andres G; Millan, Maria S, E-mail: andres.marrugo@upc.edu [Grup d' Optica Aplicada i Processament d' Imatge, Departament d' Optica i Optometria Univesitat Politecnica de Catalunya (Spain)

    2011-01-01

    Image processing, analysis and computer vision techniques are found today in all fields of medical science. These techniques are especially relevant to modern ophthalmology, a field heavily dependent on visual data. Retinal images are widely used for diagnostic purposes by ophthalmologists. However, these images often need visual enhancement prior to apply a digital analysis for pathological risk or damage detection. In this work we propose the use of an image enhancement technique for the compensation of non-uniform contrast and luminosity distribution in retinal images. We also explore optic nerve head segmentation by means of color mathematical morphology and the use of active contours.

  1. Retinal image analysis: preprocessing and feature extraction

    International Nuclear Information System (INIS)

    Image processing, analysis and computer vision techniques are found today in all fields of medical science. These techniques are especially relevant to modern ophthalmology, a field heavily dependent on visual data. Retinal images are widely used for diagnostic purposes by ophthalmologists. However, these images often need visual enhancement prior to apply a digital analysis for pathological risk or damage detection. In this work we propose the use of an image enhancement technique for the compensation of non-uniform contrast and luminosity distribution in retinal images. We also explore optic nerve head segmentation by means of color mathematical morphology and the use of active contours.

  2. Determinación de factores trombofílicos en pacientes con trombosis venosas retinianas Markers of thrombophilia in patients with retinal vein thrombosis

    Directory of Open Access Journals (Sweden)

    Leonidas Traipe C

    2005-02-01

    Full Text Available Background: Thrombophilia is an alteration of hemostasis that increases the risk to venous or arterial thrombosis. This condition may be the underlying cause of retinal vein thrombosis. Aim: To study the presence of thrombophilia in patients with retinal vein thrombosis. Patients and methods: Prospective study of 55 patients aged 22 to 86 years, with retinal vein thrombosis (central or branch. Antithrombin III, coagulant protein C, functional protein S, resistance to activated C protein, homocysteine, prothrombin G20210A gene, lupus anticoagulant and anticardiolipin antibodies were measured in all. Results: Seventeen patients had thrombophilic markers (antiphospholipid syndrome in seven, hyperhomocysteinemia in six and resistance to protein C in three. Of these 17 patients, 53% had high blood pressure, 35% an abnormal serum lipid profile and 23% a personal history of thrombosis. The thrombosis was central in 12 (ischemic in four and of a branch in five (ischemic in two. Conclusions: Thrombophilic markers must be assessed in patients with retinal vein thrombosis (Rev Méd Chile 2005; 133: 167-74

  3. Determinación de factores trombofílicos en pacientes con trombosis venosas retinianas / Markers of thrombophilia in patients with retinal vein thrombosis

    Scientific Electronic Library Online (English)

    Leonidas, Traipe C; Guillermo, Conte L; Francisco J, Conte S; Santiago, Ibáñez L; Patricio, Meza R; Basilio, Rojas U; Marianela, Cuneo V; Juan, Verdaguer T.

    2005-02-01

    Full Text Available [...] Abstract in english Background: Thrombophilia is an alteration of hemostasis that increases the risk to venous or arterial thrombosis. This condition may be the underlying cause of retinal vein thrombosis. Aim: To study the presence of thrombophilia in patients with retinal vein thrombosis. Patients and methods: Prospe [...] ctive study of 55 patients aged 22 to 86 years, with retinal vein thrombosis (central or branch). Antithrombin III, coagulant protein C, functional protein S, resistance to activated C protein, homocysteine, prothrombin G20210A gene, lupus anticoagulant and anticardiolipin antibodies were measured in all. Results: Seventeen patients had thrombophilic markers (antiphospholipid syndrome in seven, hyperhomocysteinemia in six and resistance to protein C in three). Of these 17 patients, 53% had high blood pressure, 35% an abnormal serum lipid profile and 23% a personal history of thrombosis. The thrombosis was central in 12 (ischemic in four) and of a branch in five (ischemic in two). Conclusions: Thrombophilic markers must be assessed in patients with retinal vein thrombosis (Rev Méd Chile 2005; 133: 167-74)

  4. Altered retinal flicker response indicates microvascular dysfunction in women with preeclampsia.

    Science.gov (United States)

    Brückmann, Andreas; Seeliger, Christin; Lehmann, Thomas; Schleußner, Ekkehard; Schlembach, Dietmar

    2015-10-01

    Flicker-induced dilatation is reduced in patients with cardiovascular risk, and the following arteriolar constriction is reduced with aging, leading to a reduced arteriolar amplitude and, thereby, indicating microvascular endothelial dysfunction. As endothelial dysfunction is associated with preeclampsia, we assessed retinal flicker response during pregnancy and postpartum. Between 2006 and 2013, women were recruited from University Hospital Jena and Prenatal Diagnostic Center Erfurt, Germany, of which 34 women with preeclampsia, 45 women with normal pregnancy, and 22 nonpregnant controls were included in the study. Women with normal pregnancy were matched for age, nulliparity, smoking, previous gestational hypertensive disorders, and family history of cardiovascular disease. Nonpregnant women were age-matched, nulliparous, nonsmoking, without family history of cardiovascular disease. Retinal vessel measurement using Dynamic Vessel Analyzer consisted of 50-seconds baseline acquisition, followed by three 20-second flicker and 80-second relaxation periods. Arteriolar constriction and arteriolar amplitude were reduced during pregnancy (P=0.001 and P=0.008) and postpartum (P=0.018 and P=0.034) in women with preeclampsia, adjusted for age, body mass index, mean arterial pressure, baseline diameter, and family history of cardiovascular disease. Flicker-induced dilatation was unchanged within the groups and throughout the study period. The unchanged flicker-induced dilatation may support a preserved autoregulatory competence of the microvasculature, and the diminished arteriolar amplitude, mainly because of the absence of the arteriolar constriction, indicates a commenced retinal microvascular dysfunction in women with preeclampsia during pregnancy and postpartum. Mechanisms responsible for altered retinal flicker response in preeclampsia need to be clarified in further studies. PMID:26283041

  5. Optopharmacological tools for restoring visual function in degenerative retinal diseases.

    Science.gov (United States)

    Tochitsky, Ivan; Kramer, Richard H

    2015-10-01

    Retinitis pigmentosa (RP) and age-related macular degeneration (AMD) are progressive retinal diseases that result from the death of rod and cone photoreceptors, ultimately leading to blindness. The only currently approved vision restoration treatment employs an implanted retinal 'chip' as a prosthetic device to electrically stimulate retinal neurons that survive after the photoreceptors are gone, thereby restoring light-driven neural signaling to the brain. Alternative strategies have been proposed, which would utilize optogenetic or optopharmacological tools to enable direct optical stimulation of surviving retinal neurons. Here, we review the latest studies evaluating the feasibility of these molecular tools as potential therapeutics for restoring visual function in human blinding disease. PMID:25706312

  6. Vertebral artery aneurysms.

    Directory of Open Access Journals (Sweden)

    Ravi Kumar C

    2000-04-01

    Full Text Available Vertebral artery (VA aneurysms are rare. We present our experience with three cases of VA aneurysms. Two aneurysms were located close to the origin of basilar artery while the third patient had a giant posterior inferior cerebellar artery aneurysm. These aneurysms were operated by the far lateral inferior suboccipital approach with good results.

  7. Coronary Artery Bypass Grafting

    Science.gov (United States)

    ... location of the heart. Figure B shows how vein and artery bypass grafts are attached to the heart. Overview CABG is ... if blockages form in the grafted arteries or veins or in arteries that weren't blocked before. Taking medicines and making ... NEXT >> Updated: February ...

  8. Arterial hypoxaemia in cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Hillingsø, Jens; Christensen, E; Henriksen, J H

    1998-01-01

    BACKGROUND: Although low arterial oxygen tension (Po2) has been claimed to occur in one to two thirds of patients with cirrhosis, hypoxaemia appears to be rare in clinical practice. AIMS: To assess the frequency of arterial hypoxaemia in cirrhosis in relation to clinical and haemodynamic characte...... of differing severity seems lower than previously reported, and patients with severe arterial hypoxaemia are rare....

  9. Probing how initial retinal configuration controls photochemical dynamics in retinal proteins

    Directory of Open Access Journals (Sweden)

    Sheves M.

    2013-03-01

    Full Text Available The effects of the initial retinal configuration and the active isomerization coordinate on the photochemistry of retinal proteins (RPs are assessed by comparing photochemical dynamics of two stable retinal ground state configurations (all-trans,15-anti vs. 13-cis,15-syn, within two RPs: Bacteriorhodopsin (BR and Anabaena Sensory Rhodopsin (ASR. Hyperspectral pump-probe spectroscopy shows that photochemistry starting from 13-cis retinal in both proteins is 3-10 times faster than when started in the all-trans state, suggesting that the hastening is ubiquitous to microbial RPs, regardless of their different biological functions and origin. This may also relate to the known disparity of photochemical rates between microbial RPs and visual pigments. Importance and possible underlying mechanisms are discussed as well.

  10. MDCTA diagnosis of cerebral vessel disease among patients with arterial hypertension

    International Nuclear Information System (INIS)

    to study changes involving cerebral vessels in patients with hypertension and various levels of total cardiovascular risk. One hundred and thirty-four patients underwent CT-angiography of intracranial vessels. Ninety-eight of them were diagnosed with hypertension. Taking into consideration high blood pressure, presence of risk factors and target organ damage subjects were divided into 4 groups: with low, medium, high and very high total cardiovascular risk. Control group included 36 patients. They were not diagnosed with hypertension at the time of examination. One hundred and five patients were examined using a 4-slice CT scanner (Toshiba Asteion 4, Toshiba Medical System, Japan), and 29 patients were examined using a 128-slice scanner (Siemens Definition AS+, Siemens Healthcare, Germany) with an injection system. We used iodine-containing contrast agents such as iodixanol and iopromide for angiography. Anatomical and topographic changes of cerebral vessels were most frequently found in hypertensive patients with high and very high total cardiovascular risk. Narrowing of vertebral vessels was the most common change (27 patients (27.55%), 21 patients (21.43%) had narrowing of the right artery, and 6 (6.12%) subjects – of the left one). Tortuous course of internal carotid arteries at the neck level was visualized in 11 patients (11.22%). Narrowing of A1 segment of anterior cerebral artery was noted in 9 patients (9.18%), of the right one – in 8 patients (8.16%), of the left one – in 1 patient (1.02%). Aneurysmal dilation of intracranial vessels was visualized in 6 patients (6.12%). Saccular aneurysm of left internal carotid artery was diagnosed in 2 patients (2.04%), one patient (1.02%) had right internal carotid artery aneurysm and one patient (1.02%) had an aneurysm of the basilar artery. the most common changes of cerebral vessels diagnosed in MDCTA among patients with hypertension included various degrees of narrowing of vertebral vessels, anterior, posterior and posterior communicating arteries and internal carotid arteries. Changes of middle cerebral arteries and basilar arteries were extremely rare, thus we can say that these vessels are influenced by high blood pressure to lesser extent. We established the relationship between changes in cerebral blood vessels and total cardiovascular risk. Therefore, we believe that findings will be useful for establishing prognosis in hypertension and prevention of complications such as stroke. MDCT angiography is a highly informative method to study changes of cerebral vessels in patients with hypertension. The relationship between changes in cerebral blood vessels diagnosed through MDCT angiography and the level of total cardiovascular risk among patients with hypertension had been established

  11. Analysis of the Retinal Nerve Fiber Layer in Retinitis Pigmentosa Using Optic Coherence Tomography

    OpenAIRE

    Medine Asl? Y?ld?r?m; Burak Erden; Mehmet Tetiko?lu; Özlem Kuru; Mustafa Elçio?lu

    2015-01-01

    Aim. To evaluate the peripapillary retinal nerve fiber layer (RNFL) changes in retinitis pigmentosa (RP) patients using spectral domain optic coherence tomography (Sd-OCT). Methods. We retrospectively examined medical records of forty-four eyes of twenty-two RP patients. The results were also compared with those of previously reported forty-four eyes of twenty-two normal subjects (controls). Records of average and four quadrants peripapillary RNFL thickness measurements using Sd-OCT were asse...

  12. Citomegalovirus: de la primoinfección a la retinitis / Cytomegalovirus: from primoinfection to retinitis

    Scientific Electronic Library Online (English)

    Omer, Rodríguez Martínez; Mireya, Benítez Cartaya; Isabel, Ambou Frutos; Daysi de la Caridad, Vilches Lescaille; Claudia, Hernández Cruz; Ariacna, Castro Machado.

    2014-09-01

    Full Text Available Una vez sucedida la primoinfección, el citomegalovirus se establece latente en las células mieloides progenitoras, y la reactivación viral intermitente procedente de macrófagos activados o células dendríticas es controlada por una fuerte respuesta viral específica de células CD4 y CD8. La retinitis [...] por citomegalovirus está caracterizada por una necrosis retinal como consecuencia de efectos citopáticos virales que ocurre en pacientes en quienes la función de células T está comprometida, como resultado de trasplantes de órganos, SIDA o tratamiento inmunosupresor. El diagnóstico de retinitis por citomegalovirus puede ser confirmado por amplificación del ADN viral en muestras de humor acuoso. El tratamiento de la retinitis por citomegalovirus se basa en la actualidad en la reconstitución del sistema inmune con la terapia TARGA y combinado a una terapia anticitomegalovirus (ganciclovir, foscarnet, cidofovir y valganciclovir). El citomegalovirus está también implicado en dos formas de enfermedad del segmento anterior en adultos inmunocompetentes llamado uveítis anterior por citomegalovirus y queratitis endotelial por citomegalovirus. Abstract in english Once first infection occurs, cytomegalovirus (CMV) remains latent in myeloid progenitor cells and the intermittent viral relapsing proceeding from activated macrophages and dendritic cells, is controlled by strong specific viral response CD4cell y CD8-cell. CMV retinitis is characterized by spreadin [...] g retinal necrosis due to viral cytopathic effect occurs in patients who have impaired T-cell function as a result of transplantation, AIDS, or immuno-suppressive treatment. The diagnosis of CMV retinitis can be confirmed by PCR amplification of viral DNA in aqueous. Updated treatment for CMV retinitis is based on the immune system recovery with highly activity anti-retroviral therapy combined with anti CMV therapy (ganciclovir, foscarnet, cidofovir and valganciclovir). CMV is also implicated in two forms of anterior segment disease in immuno-competent adults, namely CMV anterior uveitis and CMV corneal endotheliitis.

  13. A CMOS LSI-Based Flexible Retinal Stimulator for Retinal Prosthesis

    Science.gov (United States)

    Tokuda, Takashi; Sugitani, Sachie; Asano, Ryosuke; Taniyama, Mari; Terasawa, Yasuo; Uehara, Akihiro; Kagawa, Keiichiro; Nunoshita, Masahiro; Tano, Yasuo; Ohta, Jun

    A CMOS LSI-based neural stimulator was developed for retinal prosthesis. The stimulator was designed with “multi-chip” architecture. Small LSI neural stimulators named “Unit Chip” were assembled on a flexible substrate into a flexible, multi-site retinal stimulator. An experimental system equipped with the fabricated LSI-based flexible stimulator was configured and current injection functionality was demonstrated in saline solution. Materials for improved charge injection were also discussed.

  14. Cytomegalovirus retinitis after central retinal vein occlusion in a patient on systemic immunosuppression: does venooclusive disease predispose to cytomegalovirus retinitis in patients already at risk?

    Directory of Open Access Journals (Sweden)

    Welling JD

    2012-04-01

    Full Text Available John D Welling, Ahmad B Tarabishy, John ChristoforidisDepartment of Ophthalmology, Havener Eye Institute, Ohio State University, Columbus, OH, USAAbstract: Cytomegalovirus (CMV retinitis remains the most common opportunistic ocular infection in immunocompromised patients. Patients with immunocompromising diseases, such as acquired immunodeficiency syndrome, inherited immunodeficiency states, malignancies, and those on systemic immunosuppressive therapy, are known to be at risk. Recently, it has been suggested that patients undergoing intravitreal injection of immunosuppressive agents may also be predisposed. One previous case report speculated that there may be an additional risk for CMV retinitis in acquired immunodeficiency syndrome patients with venoocclusive disease. This case study presents a case of CMV retinitis following central retinal vein occlusion in a patient on systemic immunosuppressants.Keywords: cytomegalovirus retinitis, central retinal vein occlusion, immunosuppression, solid organ transplant, venous stasis, risk factor

  15. Potential for Autoimmune Pathogenesis of Rift Valley Fever Virus Retinitis

    Science.gov (United States)

    Newman-Gerhardt, Shoshana; Muiruri, Samuel; Muchiri, Eric; Peters, Clarence J.; Morrill, John; Lucas, Alexander H.; King, Charles H.; Kazura, James; LaBeaud, Angelle Desiree

    2013-01-01

    Rift Valley Fever (RVF) is a significant threat to human health because it can progress to retinitis, encephalitis, and hemorrhagic fever. The timing of onset of Rift Valley Fever virus (RVFV) retinitis suggests an autoimmune origin. To determine whether RVFV retinitis is associated with increased levels of IgG against retinal tissue, we measured and compared levels of IgG against healthy human eye tissue by immunohistochemical analysis. We found that serum samples from RVFV-exposed Kenyans with retinitis (n = 8) were slightly more likely to have antibodies against retinal tissue than control populations, but the correlation was not statistically significant. Further investigation into the possible immune pathogenesis of RVFV retinitis could lead to improved therapies to prevent or treat this severe complication. PMID:23918215

  16. Ground-state properties of the retinal molecule: from quantum mechanical to classical mechanical computations of retinal proteins

    Energy Technology Data Exchange (ETDEWEB)

    Suhai, Sandor [German Cancer Research Center, Heidelberg

    2011-01-01

    Retinal proteins are excellent systems for understanding essential physiological processes such as signal transduction and ion pumping. Although the conjugated polyene system of the retinal chromophore is best described with quantum mechanics, simulations of the long-timescale dynamics of a retinal protein in its physiological, flexible, lipid-membrane environment can only be performed at the classical mechanical level. Torsional energy barriers are a critical ingredient of the classical force-field parameters. Here we review briefly current retinal force fields and discuss new quantum mechanical computations to assess how the retinal Schiff base model and the approach used to derive the force-field parameters may influence the torsional potentials.

  17. Progressive outer retinal necrosis (PORN) in AIDS patients: a different appearance of varicella-zoster retinitis.

    Science.gov (United States)

    Pavesio, C E; Mitchell, S M; Barton, K; Schwartz, S D; Towler, H M; Lightman, S

    1995-01-01

    Retinal infections caused by the varicella-zoster virus (VZV) have been reported in immunocompetent and immunocompromised individuals. Two cases of a VZV-related retinitis are described with the characteristic features of the recently described progressive outer retinal necrosis (PORN) syndrome. Both patients suffered from the acquired immunodeficiency syndrome (AIDS) with greatly reduced peripheral blood CD4+ T lymphocyte counts, and presented with macular retinitis without vitritis. The disease was bilateral in one case and unilateral in the other. The clinical course was rapidly progressive with widespread retinal involvement and the development of rhegmatogenous retinal detachment with complete loss of vision in the affected eyes despite intensive intravenous antiviral therapy. VZV DNA was identified in vitreous biopsies, by molecular techniques based on the polymerase chain reaction (PCR), in both patients. At present, the use of very high-dose intravenous acyclovir may be the best therapeutic option in these patients for whom the visual prognosis is poor. Intravitreal antiviral drugs could also contribute to the management of these cases. PMID:7556731

  18. Retinal nerve fiber layer thickness map

    Science.gov (United States)

    Mujat, Mircea; Chan, Raymond C.; Cense, Barry; Park, Hyle; Joo, Chulmin; Chen, Teresa C.; de Boer, Johannes F.

    2006-02-01

    Spectral-Domain Optical Coherence Tomography (SDOCT) allows for in-vivo video-rate investigation of biomedical tissue depth structure with the purpose of non-invasive optical diagnostics. In ophthalmic applications, it has been suggested that Optical Coherence Tomography (OCT) can be used for diagnosis of glaucoma by measuring the thickness of the Retinal Nerve Fiber Layer (RNLF). We present here an automated method for determining the RNFL thickness map from a 3-D dataset. Boundary detection has been studied since the early days of computer vision and image processing, and different approaches have been proposed. The procedure described here is based on edge detection using a deformable spline (snake) algorithm. As the snake seeks to minimize its overall energy, its shape will converge on the image contour, the boundaries of the nerve fiber layer. In general, the snake is not allowed to travel too much, and therefore, proper initialization is required. The snake parameters, elasticity, rigidity, viscosity, and external force weight are set to allow the snake to follow the boundary for a large number of retinal topographies. The RNFL thickness map is combined with an integrated reflectance map of the retina and retinal cross-sectional images (OCT movie), to provide the ophthalmologist with a familiar image for interpreting the OCT data. The video-rate capabilities of our SDOCT system allow for mapping the true retinal topography since the motion artifacts are significantly reduced as compared to slower time-domain systems.

  19. A continuum model of retinal electrical stimulation

    Science.gov (United States)

    Joarder, Saiful A.; Abramian, Miganoosh; Suaning, Gregg J.; Lovell, Nigel H.; Dokos, Socrates

    2011-10-01

    A continuum mathematical model of retinal electrical stimulation is described. The model is represented by a passive vitreous domain, a thin layer of active retinal ganglion cell (RGC) tissue adjacent to deeper passive neural layers of the retina, the retinal pigmented epithelium (RPE) and choroid thus ending at the sclera. To validate the model, in vitro epiretinal responses to stimuli from 50 µm disk electrodes, arranged in a hexagonal mosaic, were recorded from rabbit retinas. 100 µs/phase anodic-first biphasic current pulses were delivered to the retinal surface in both the mathematical model and experiments. RGC responses were simulated and recorded using extracellular microelectrodes. The model's epiretinal thresholds compared favorably with the in vitro data. In addition, simulations showed that single-return bipolar electrodes recruited a larger area of the retina than twin-return or six-return electrodes arranged in a hexagonal layout in which a central stimulating electrode is surrounded by six, eqi-spaced returns. Simulations were also undertaken to investigate the patterns of RGC activation in an anatomically-accurate model of the retina, as well as RGC activation patterns for subretinal and suprachoroidal bipolar stimulation. This paper was originally submitted for the special issue containing contributions from the Sixth Biennial Research Congress of The Eye and the Chip.

  20. Idiopathic infantile chronic rhegmatogenous retinal detachment.

    Science.gov (United States)

    Aziz, Hassan A; Berrocal, Audina M; Sisk, Robert A; Murray, Timothy G

    2011-01-01

    The authors describe a 3-month-old female infant with infantile rhegmatogenous retinal detachment with no associated congenital or developmental abnormalities. The unique presentation of this patient indicates that the detachment was a result of an early developmental defect. PMID:21751768

  1. A Psychophysical Test for Retinitis Pigmentosa.

    Science.gov (United States)

    Corwin, Thomas R; Mancini, Michael

    A new test designed to detect an hereditary eye disease called retinitis pigmentosa (RP) is described. This condition is revealed by pigmentation in the retina, but early diagnosis is difficult because the symptoms are subtle, and since it is genetically recessive it frequently occurs in families with no history of early blindness. In many cases…

  2. The Retinitis Pigmentosa Student: Selected Aspects.

    Science.gov (United States)

    Sullivan, Franklin N.

    1984-01-01

    The characteristic features of RP (retinitis pigmentosa-an untreatable conditions usually resulting in night blindness) are discussed and functioning considerations in the classroom (including the use of protective devices and mobility aids) are noted. Classroom modifications such as darklined paper and black pens are suggested. (CL)

  3. Photovoltaic Retinal Prosthesis with High Pixel Density.

    Science.gov (United States)

    Mathieson, Keith; Loudin, James; Goetz, Georges; Huie, Philip; Wang, Lele; Kamins, Theodore I; Galambos, Ludwig; Smith, Richard; Harris, James S; Sher, Alexander; Palanker, Daniel

    2012-06-01

    Retinal degenerative diseases lead to blindness due to loss of the "image capturing" photoreceptors, while neurons in the "image processing" inner retinal layers are relatively well preserved. Electronic retinal prostheses seek to restore sight by electrically stimulating surviving neurons. Most implants are powered through inductive coils, requiring complex surgical methods to implant the coil-decoder-cable-array systems, which deliver energy to stimulating electrodes via intraocular cables. We present a photovoltaic subretinal prosthesis, in which silicon photodiodes in each pixel receive power and data directly through pulsed near-infrared illumination and electrically stimulate neurons. Stimulation was produced in normal and degenerate rat retinas, with pulse durations from 0.5 to 4 ms, and threshold peak irradiances from 0.2 to 10 mW/mm(2), two orders of magnitude below the ocular safety limit. Neural responses were elicited by illuminating a single 70 ?m bipolar pixel, demonstrating the possibility of a fully-integrated photovoltaic retinal prosthesis with high pixel density. PMID:23049619

  4. Laser photocoagulation for retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    K. A. Mirzabekova

    2015-03-01

    Full Text Available Retinal vein occlusion (RVO is one of the leading causes of permanent vision loss. In adults, central retinal vein occlusion (CRVO occurs in 1.8% while branch retinal vein occlusion (BRVO occurs in 0.2%. Treatment strategy and disease prognosis are determined by RVO type (ischemic/non-ischemic. Despite numerous studies and many current CRVO and BRVO treatment approaches, the management of these patients is still being debated. Intravitreal injections of steroids (triamcinolone acetate, dexamethasone and vascular endothelial growth factor (VEGF inhibitors (bevacizumab, ranibizumab were shown to be fairly effective. However, it is unclear whether anti-VEGF agents are reasonable in ischemic RVOs. Laser photocoagulation remains the only effective treatment of optic nerve head and/or retinal neovascularization. Laser photocoagulation is also indicated for the treatment of macular edema. Both threshold and sub-threshold photocoagulation may be performed. Photocoagulation performed with argon (514 nm, krypton (647 nm, or diode (810 nm laser for macular edema provides similar results (no significant differences. The treatment may be complex and include medication therapy and/or surgery. Medication therapy includes anti-aggregant agents and antioxidants, i.e., emoxypine which may be used in acute RVO as well as in post-thrombotic retinopathy. 

  5. Intravitreal ganciclovir in CMV retinitis: case report.

    OpenAIRE

    Harris, M. L.; Mathalone, M B

    1989-01-01

    A case is reported of a 35-year-old male with established acquired immune deficiency syndrome who developed cytomegalovirus retinitis. When intravenous treatment with ganciclovir had to be withdrawn because of toxicity, one eye was treated successfully by intravitreal injections of the drug. After 15 weeks of intravitreal treatment this eye developed endophthalmitis.

  6. Retinal Imaging Techniques for Diabetic Retinopathy Screening.

    Science.gov (United States)

    Goh, James Kang Hao; Cheung, Carol Y; Sim, Shaun Sebastian; Tan, Pok Chien; Tan, Gavin Siew Wei; Wong, Tien Yin

    2016-01-01

    Due to the increasing prevalence of diabetes mellitus, demand for diabetic retinopathy (DR) screening platforms is steeply increasing. Early detection and treatment of DR are key public health interventions that can greatly reduce the likelihood of vision loss. Current DR screening programs typically employ retinal fundus photography, which relies on skilled readers for manual DR assessment. However, this is labor-intensive and suffers from inconsistency across sites. Hence, there has been a recent proliferation of automated retinal image analysis software that may potentially alleviate this burden cost-effectively. Furthermore, current screening programs based on 2-dimensional fundus photography do not effectively screen for diabetic macular edema (DME). Optical coherence tomography is becoming increasingly recognized as the reference standard for DME assessment and can potentially provide a cost-effective solution for improving DME detection in large-scale DR screening programs. Current screening techniques are also unable to image the peripheral retina and require pharmacological pupil dilation; ultra-widefield imaging and confocal scanning laser ophthalmoscopy, which address these drawbacks, possess great potential. In this review, we summarize the current DR screening methods using various retinal imaging techniques, and also outline future possibilities. Advances in retinal imaging techniques can potentially transform the management of patients with diabetes, providing savings in health care costs and resources. PMID:26830491

  7. Unsupervised Retinal Vessel Segmentation Using Combined Filters

    Science.gov (United States)

    Oliveira, Wendeson S.; Teixeira, Joyce Vitor; Ren, Tsang Ing; Cavalcanti, George D. C.; Sijbers, Jan

    2016-01-01

    Image segmentation of retinal blood vessels is a process that can help to predict and diagnose cardiovascular related diseases, such as hypertension and diabetes, which are known to affect the retinal blood vessels’ appearance. This work proposes an unsupervised method for the segmentation of retinal vessels images using a combined matched filter, Frangi’s filter and Gabor Wavelet filter to enhance the images. The combination of these three filters in order to improve the segmentation is the main motivation of this work. We investigate two approaches to perform the filter combination: weighted mean and median ranking. Segmentation methods are tested after the vessel enhancement. Enhanced images with median ranking are segmented using a simple threshold criterion. Two segmentation procedures are applied when considering enhanced retinal images using the weighted mean approach. The first method is based on deformable models and the second uses fuzzy C-means for the image segmentation. The procedure is evaluated using two public image databases, Drive and Stare. The experimental results demonstrate that the proposed methods perform well for vessel segmentation in comparison with state-of-the-art methods. PMID:26919587

  8. Retinal Biochemistry, Physiology and Cell Biology.

    Science.gov (United States)

    Smith, Ricardo Luiz; Sivaprasad, Sobha; Chong, Victor

    2016-01-01

    The vitreous, the vasculature of the retina, macular pigments, phototransduction, retinal pigment epithelium, Bruch's membrane and the extracellular matrix, all play an important role in the normal function of the retina as well as in diseases. Understanding the pathophysiology allows us to target treatment. As ocular angiogenesis, immunity and inflammation are covered elsewhere, those subjects will not be discussed in this chapter. PMID:26502005

  9. Jet pump assisted artery

    Science.gov (United States)

    1975-01-01

    A procedure for priming an arterial heat pump is reported; the procedure also has a means for maintaining the pump in a primed state. This concept utilizes a capillary driven jet pump to create the necessary suction to fill the artery. Basically, the jet pump consists of a venturi or nozzle-diffuser type constriction in the vapor passage. The throat of this venturi is connected to the artery. Thus vapor, gas, liquid, or a combination of the above is pumped continuously out of the artery. As a result, the artery is always filled with liquid and an adequate supply of working fluid is provided to the evaporator of the heat pipe.

  10. Sealing of retinal breaks with metal tacks. Evaluation of a new procedure in retinal re-attachment surgery.

    Science.gov (United States)

    Algvere, P; Stenkula, S; Crafoord, S; Unosson, K; Berglin, L

    1986-08-01

    Metal retinal tacks were used in 18 patients with complicated retinal detachments, such as giant tears (3 cases), severe proliferative vitreoretinopathy (PVR) (7 eyes) and diabetic traction and rhegmatogenous detachment (8 cases). All eyes had undergone vitreous microsurgery, including excision or segmentation of epiretinal membranes, fluid-air (SF6) or silicone oil exchange. Retinal breaks and the cut edges of retinotomies and retinectomies were successfully sealed by metal tacks. Retinal re-attachment was achieved in 9 cases and partial re-attachment in another 5 eyes (follow-up 3-6 months). Retinal tears in diabetic macular detachment associated with extensive epiretinal fibrovascular membranes were also successfully sealed despite persisting traction. Our first experience indicates that the closing of retinal breaks with metal tacks is a major step forward in retinal re-attachment surgery. PMID:3535367

  11. Central retinal vein occlusion in an otherwise healthy child treated successfully with a single injection of bevacizumab.

    Science.gov (United States)

    Zheng, Linda; Gillies, Mark; Martin, Frank J

    2015-10-01

    We describe the case of an otherwise healthy 13-year-old boy who presented with blurred vision and deteriorating visual acuity in his left eye. Fundus examination showed left optic disk swelling, exudates, and hemorrhages. He was found to have an elevated left central retinal venous pressure to the level of arterial diastolic pressure, an elevated left central macular thickness and a prolonged disk-to-disk transit time on fluorescein angiography, which confirmed the diagnosis of unilateral central retinal vein occlusion (CRVO). The child was treated with one injection of bevacizumab. He has maintained visual acuity of 6/6 for 2 years following treatment, despite persistent elevated left central venous pressure and chronic optic disk edema. PMID:26486035

  12. Changes in retinal nerve fiber layer thickness after spinal surgery in the prone position: a prospective study

    Directory of Open Access Journals (Sweden)

    Baran Gencer

    2015-02-01

    Full Text Available BACKGROUND AND OBJECTIVES: Changes in ocular perfusion play an important role in the pathogenesis of ischemic optic neuropathy. Ocular perfusion pressure is equal to mean arterial pressure minus intraocular pressure. The aim of this study was to evaluate the changes in the intraocular pressure and the retinal nerve fiber layer thickness in patients undergoing spinal surgery in the prone position. METHODS: This prospective study included 30 patients undergoing spinal surgery. Retinal nerve fiber layer thickness were measured one day before and after the surgery by using optical coherence tomography. Intraocular pressure was measured by tonopen six times at different position and time-duration: supine position (baseline; 10 min after intubation (Supine 1; 10 (Prone 1, 60 (Prone 2, 120 (Prone 3 min after prone position; and just after postoperative supine position (Supine 2. RESULTS: Our study involved 10 male and 20 female patients with the median age of 57 years. When postoperative retinal nerve fiber layer thickness measurements were compared with preoperative values, a statistically significant thinning was observed in inferior and nasal quadrants (p = 0.009 and p = 0.003, respectively. We observed a statistically significant intraocular pressure decrease in Supine 1 and an increase in both Prone 2 and Prone 3 when compared to the baseline. Mean arterial pressure and ocular perfusion pressure were found to be significantly lower in Prone 1, Prone 2 and Prone 3, when compared with the baseline. CONCLUSIONS: Our study has shown increase in intraocular pressure during spinal surgery in prone position. A statistically significant retinal nerve fiber layer thickness thinning was seen in inferior and nasal quadrants one day after the spinal surgery.

  13. Prophylactic treatment of retinal breaks : a systematic review

    DEFF Research Database (Denmark)

    Blindbæk, SØren Leer; Grauslund, Jakob

    2015-01-01

    Prophylactic treatment of retinal breaks has been examined in several studies and reviews, but so far, no studies have successfully applied a systematic approach. In the present systematic review, we examined the need of follow-up after posterior vitreous detachment (PVD) - diagnosed by slit-lamp biomicroscopy or Goldmann 3-mirror examination - with regard to retinal breaks as well as the indication of prophylactic treatment in asymptomatic and symptomatic breaks. A total of 2941 publications were identified with PubMed and Medline searches. Two manual search strategies were used for papers in English published before 2012. Four levels of screening identified 13 studies suitable for inclusion in this systematic review. No meta-analysis was conducted as no data suitable for statistical analysis were identified. In total, the initial examination after symptomatic PVD identified 85-95% of subsequent retinal breaks. Additional retinal breaks were only revealed at follow-up in patients where a full retinal examination was compromised at presentation by, for example, vitreous haemorrhage. Asymptomatic and symptomatic retinal breaks progressed to rhegmatogenous retinal detachment (RRD) in 0-13.8% and 35-47% of cases, respectively. The cumulated incidence of RRD despite prophylactic treatment was 2.1-8.8%. The findings in this review suggest that follow-up after symptomatic PVD is only necessary in cases of incomplete retinal examination at presentation. Prophylactic treatment of symptomatic retinal breaks must be considered, whereas no unequivocal conclusion could be reached with regard to prophylactic treatment of asymptomatic retinal breaks.

  14. Regional morphology and pathophysiology of retinal vascular disease

    DEFF Research Database (Denmark)

    Bek, Toke

    2013-01-01

    Disturbances in the retinal vascular supply are involved in the pathophysiology of the most frequent diseases causing visual impairment and blindness in the Western World. These diseases are diagnosed by noting how morphological lesions in the retina vary in shape, size, location and dynamics, and subsequently concluding the presence of a specific disease entity. This diagnostic approach can be used to identify the site of a retinal vascular occlusion, to assess whether retinal diseases are primarily due to changes in the larger retinal vessels or the microcirculation, and to differentiate the relative involvement of the choroidal and the retinal vascular systems. However, a number of morphological manifestations of retinal vascular disease cannot presently be related to the underlying pathophysiology. The review concludes that there is a need for developing new methods for assessing vascular structure and function in the ciliary vascular system supplying the choroid and the optic nerve head. Presently, the study of these structures relies on imaging techniques with limited penetration and resolution into the tissue. Secondly, there is a need for studying oscillations in retinal vascular function occurring within days to weeks, and for studying regional manifestations of retinal vascular disease. This may constitute the basis for future research in retinal vascular pathophysiology and for the development of new treatment modalities to reduce blindness secondary to retinal vascular disease.

  15. 23-Gauge Sutureless Vitreo-Retinal Surgery for Superior Rhegmatogenous Retinal Detachment

    International Nuclear Information System (INIS)

    Objective: To determine the results of 23-gauge sutureless vitreo-retinal surgery for superior/supero-temporal rhegmatogenous retinal detachment (RRD). Study Design: Quasi experimental study. Place and Duration of Study: LRBT, Free Base Eye Hospital, Karachi, from January 2010 to December 2011. Methodology: Adult patients who underwent 23-gauge sutureless vitreo-retinal surgery along with use of Perfluoropropane (C3F8) gas as internal tamponading agent for fresh (upto 3 weeks) superior/supero-temporal RRD was reviewed. Major outcome measures were anatomical success, best corrected visual acuity (BCVA) with Log Mar and complications during and after surgery. Postoperative follow-up was done on 1st day and at 1st, 4th, 8th and finally at 12th week. Results: Sixty eyes of 60 patients, age between 30 - 60 years including 37 (61.67%) males and 23 (38.33%) females having superior or superatemporal RRD underwent 23-guage sutureless vitreo-retinal surgery with the use of perfluoropropane (C3 F8) gas as internal temponade at the end of procedure. Anatomical success rate was 81.66% (49 out of 60 eyes) with first surgery and raised to 90% (54 cases) with second surgery. Log Mar BCVA significantly improved from mean baseline 0.93 to 0.49 with mean difference of 0.43 (p < 0.001), 95% confidence interval. Postoperative complications were sub-conjunctival haemorrhage in 11 eyes (18.33%), wound leak in 7 eyes (11.66%), anterior chamber became shallow in 6 eyes (10%), cataract developed in 5 eyes (8.33%), re-retinal detachment in 4 eyes (6.66%), ocular hypotony and sterile inflammatory reaction in 3 eyes (5%) each, while iatrogenic breaks developed in 2 eyes (3.33%). Conclusion: The 23-gauge sutureless vitreo-retinal surgery for superior rhegmatogenous retinal detachment achieved high anatomical success and significant visual improvement. Sub-conjunctival haemorrhage was the most frequent procedural complication. (author)

  16. Inner retinal change in a novel rd1-FTL mouse model of retinal degeneration

    Directory of Open Access Journals (Sweden)

    Michael Kalloniatis

    2015-07-01

    Full Text Available While photoreceptor loss is the most devastating result of inherited retinal degenerations such as retinitis pigmentosa, inner retinal neurons also undergo significant alteration. Detailing these changes has become important as many vision restorative therapies target the remaining neurons. In this study, the rd1-Fos-Tau-LacZ (rd1-FTL mouse model was used to explore inner retinal change at a late stage of retinal degeneration, after the loss of photoreceptor nuclei. The rd1-FTL model carries a mutation in the phosphodiesterase gene, Pde6b, and an axonally targeted transgenic beta galactosidase reporter system under the control of the c-fos promoter. Retinae of transgenic rd1-FTL mice and control FTL animals aged 2 to 12 months were processed for indirect fluorescence immunocytochemistry. At 2 months of age, a time when the majority of photoreceptor nuclei are lost, there was negligible c-fos reporter (FTL expression, however, from 4 months, reporter expression was observed to increase within subpopulations of amacrine and ganglion cells within the central retina. These areas of inner retinal FTL expression coincided with regions that contained aberrant Müller cells. Specifically, these cells exhibited reduced glutamine synthetase and Kir4.1 immunolabelling, whilst showing evidence of proliferative gliosis (increased cyclinD1 and GFAP expression. These changes were limited to distinct regions where cone photoreceptor terminals were absent. Overall, these results highlight that distinct areas of the rd1-FTL central retina undergo significant glial alterations after cone photoreceptor loss. These areas coincide with up-regulation of the c-fos reporter in the inner retina, which may represent a change in neuronal function/plasticity. The rd1-FTL mouse is a useful model system to probe changes that occur in the inner retina at later stages of retinal degeneration.

  17. Retinal arteriolar responses to acute severe elevation in systemic blood pressure in cats: role of endothelium-derived factors.

    Science.gov (United States)

    Nakabayashi, Seigo; Nagaoka, Taiji; Tani, Tomofumi; Sogawa, Kenji; Hein, Travis W; Kuo, Lih; Yoshida, Akitoshi

    2012-10-01

    The purpose of this study was to investigate the roles of endothelium-derived factors in the retinal arteriolar responses to acute severe elevation in systemic blood pressure (BP) in cats. Acute elevation of mean arterial BP by 60% for 5 min was achieved by inflating a balloon-tipped catheter in the descending aorta. The retinal arteriolar diameter, flow velocity, wall shear rate (WSR) and blood flow (RBF) changes during BP elevation were assessed with laser Doppler velocimetry 2 h after intravitreal injections of nitric oxide (NO) synthase inhibitor l-NAME, cyclooxygenase inhibitor indomethacin, endothelin-1 receptor antagonists (BQ-123 for type A and BQ-788 for type B), or Rho kinase inhibitor fasudil. BP elevation caused a marked increase in retinal arteriolar flow velocity and WSR with slight vasoconstriction, resulting in an increase in RBF. The increases in velocity, WSR and RBF, but not diameter, were correlated with the increase in ocular perfusion pressure. With l-NAME or indomethacin, the increase in RBF upon BP elevation was significantly attenuated due to enhanced retinal arteriolar vasoconstriction. In contrast, BQ-123 and fasudil potentiated the increased RBF. BQ-788 had no effect on arteriolar diameter and hemodynamics. Our data suggest that acute elevation of BP by 60% leads to an increase in RBF due to the release of NO and prostanoids probably through a shear stress-induced vasodilation mechanism. The release of endothelin-1 and Rho kinase activation help to limit RBF augmentation by counteracting the vasodilation. It appears that the retinal endothelium, by releasing vasoactive substances, contributes to RBF regulation during acute severe elevation of systemic blood pressure. PMID:22940370

  18. Retinal area detector from scanning laser ophthalmoscope (SLO) images for diagnosing retinal diseases.

    Science.gov (United States)

    Haleem, Muhammad Salman; Han, Liangxiu; van Hemert, Jano; Li, Baihua; Fleming, Alan

    2015-07-01

    Scanning laser ophthalmoscopes (SLOs) can be used for early detection of retinal diseases. With the advent of latest screening technology, the advantage of using SLO is its wide field of view, which can image a large part of the retina for better diagnosis of the retinal diseases. On the other hand, during the imaging process, artefacts such as eyelashes and eyelids are also imaged along with the retinal area. This brings a big challenge on how to exclude these artefacts. In this paper, we propose a novel approach to automatically extract out true retinal area from an SLO image based on image processing and machine learning approaches. To reduce the complexity of image processing tasks and provide a convenient primitive image pattern, we have grouped pixels into different regions based on the regional size and compactness, called superpixels. The framework then calculates image based features reflecting textural and structural information and classifies between retinal area and artefacts. The experimental evaluation results have shown good performance with an overall accuracy of 92%. PMID:25167560

  19. Right coronary artery aneurysm

    OpenAIRE

    Luz, A; Silveira, J.; Cyrne-Carvalho, H.; Gomes, L.

    2007-01-01

    Int J Cardiol. 2007 Jan 18;114(3):e122-3. Epub 2006 Oct 16. Right coronary artery aneurysm. Luz A, Silveira J, Carvalho H, Gomes L. Abstract Coronary artery aneurysms, characterized by abnormal dilatations of a localized portion of the coronary artery, are an uncommon finding during angiography. We present a case where a giant right coronary aneurysm was detected during angiography, in a patient admitted with a inferior wall myocardial infarction. PMID: 17049395 [PubMed - inde...

  20. Hepatic Artery Infusion Chemotherapy

    OpenAIRE

    Tuchmann, A.; Schüller, J.; Kroiss, A.; Dinstl, K.

    1990-01-01

    Hepatic artery chemotherapy was given to 36 patients, using totally implantable devices consisting of a port and external pump. Twenty-seven patients had inoperable liver metastases of colorectal origin. The infusion system was inserted by laparotomy into the hepatic artery via the gastroduodenal artery. There was no operative mortality. Thirteen infusion systems could not be used for chemotherapy due to dislodgement, early death and lack of follow-up. FUdR was infused every two weeks. There ...

  1. Popliteal artery entrapment syndrome.

    LENUS (Irish Health Repository)

    O'Leary, D P

    2010-01-01

    Popliteal artery entrapment syndrome is a rare abnormality of the anatomical relationship between the popliteal artery and adjacent muscles or fibrous bands in the popliteal fossa. The following is a case report of a 19 year old female, in whom popliteal artery entrapment syndrome was diagnosed, and successfully treated surgically. A review of literature is also presented and provides details on how PAES is classified, diagnosed both clinically and radiologically, and treated surgically.

  2. Ruptured visceral artery aneurysms.

    Science.gov (United States)

    Chiaradia, M; Novelli, L; Deux, J-F; Tacher, V; Mayer, J; You, K; Djabbari, M; Luciani, A; Rahmouni, A; Kobeiter, H

    2015-01-01

    Visceral artery aneurysms are rare but their estimated mortality due to rupture ranges between 25 and 70%. Treatment of visceral artery aneurysm rupture is usually managed by interventional radiology. Specific embolization techniques depend on the location, affected organ, locoregional arterial anatomy, and interventional radiologist skill. The success rate following treatment by interventional radiology is greater than 90%. The main complication is recanalization of the aneurysm, showing the importance of post-therapeutic monitoring, which should preferably be performed using MR imaging. PMID:26054246

  3. Duplicated middle cerebral artery

    OpenAIRE

    Perez, Jesus; Machado, Calixto; Scherle, Claudio; Hierro, Daniel

    2009-01-01

    Duplicated middle cerebral artery (DMCA) is an anomalous vessel arising from the internal carotid artery. The incidence DMCA is relatively law, and an association between this anomaly and cerebral aneurysms has been documented. There is a controversy whether DMCA may have perforating arteries. This is an important fact to consider in aneurysm surgery. We report the case of a 34-year-old black woman who suffered a subarachnoid hemorrhage and the angiography a left DMCA, and an aneurysm in an i...

  4. Unexplained postoperative retinal hemorrhage after 23-gauge sutureless vitrectomy

    Directory of Open Access Journals (Sweden)

    Ohno H

    2011-07-01

    Full Text Available Hisato Ohno, Kenji InoueInouye Eye Hospital, Tokyo, JapanAbstract: We report five cases of unexplained retinal hemorrhage after 23-gauge sutureless vitrectomy. A 23-gauge sutureless vitrectomy was performed for four cases of macular holes (MH and one case of macular hole retinal detachment (MHRD. Retinal hemorrhages were observed on the first day after surgery and disappeared within several months without leaving any recognizable damage. We speculate that the retinal hemorrhages might have resulted from repeated collapse of the globe through a cannula under air perfusion, but other causes such as retinal vein congestion by face-down positioning are also possible.Keywords: retinal hemorrhage, vitrectomy, postoperative, macular hole, sutureless surgery

  5. Intralobar pulmonary sequestration with aberrant systemic artery-pulmonary vein fistula -a case report-

    International Nuclear Information System (INIS)

    Intralobar pulmonary sequestration combined with aberrant systemic a tery-pulmonary vein fistula is rare congenital malformation. Authors experienced a case of intralobar pulmonary sequestration combined with arteriovenous fistula in left lower lung. The patient was 8 year-old male whose complaint was dyspnea on exertion. The continuous murmur was heard over the left posterior chest wall. The chest film showed multiple tortuous branching tubular shadows in the left lower lung field and dilated pulmonary vein at the infrahilar area. Thoracic aortogram showed that aberrant systemic artery originated from lower thoracic aorta and the arterial blood drained into left atrium directly through dilated left lower pulmonary vein. Left pulmonary arteriogram revealed that there was no vascular supply in the posterior basal segment of left lower lobe. At the time of operation, pulmonary sequestration was located in the posterior basal segment of left lower lobe and enveloped by the same visceral pleura. A segmentectomy of left lower lobe with ligation of aberrant vessels was performed

  6. Stability of carotid artery under steady-state and pulsatile blood flow: a fluid-structure interaction study.

    Science.gov (United States)

    Saeid Khalafvand, Seyed; Han, Hai-Chao

    2015-06-01

    It has been shown that arteries may buckle into tortuous shapes under lumen pressure, which in turn could alter blood flow. However, the mechanisms of artery instability under pulsatile flow have not been fully understood. The objective of this study was to simulate the buckling and post-buckling behaviors of the carotid artery under pulsatile flow using a fully coupled fluid-structure interaction (FSI) method. The artery wall was modeled as a nonlinear material with a two-fiber strain-energy function. FSI simulations were performed under steady-state flow and pulsatile flow conditions with a prescribed flow velocity profile at the inlet and different pressures at the outlet to determine the critical buckling pressure. Simulations were performed for normal (160 ml/min) and high (350 ml/min) flow rates and normal (1.5) and reduced (1.3) axial stretch ratios to determine the effects of flow rate and axial tension on stability. The results showed that an artery buckled when the lumen pressure exceeded a critical value. The critical mean buckling pressure at pulsatile flow was 17-23% smaller than at steady-state flow. For both steady-state and pulsatile flow, the high flow rate had very little effect (buckling pressure. The fluid and wall stresses were drastically altered at the location with maximum deflection. The maximum lumen shear stress occurred at the inner side of the bend and maximum tensile wall stresses occurred at the outer side. These findings improve our understanding of artery instability in vivo. PMID:25761257

  7. Alterations of Retinal Vasculature in Cystathionine-Beta-Synthase Mutant Mice, a Model of Hyperhomocysteinemia

    OpenAIRE

    Tawfik, Amany; AL-SHABRAWEY, MOHAMED; Roon, Penny; Sonne, Srinivas; Covar, Jason A.; Matragoon, Surapoon; Ganapathy, Preethi S.; Atherton, Sally S.; El-Remessy, Azza; Ganapathy, Vadivel; Smith, Sylvia B.

    2013-01-01

    Hyperhomocysteinemia, due to lack of CBS, is associated with marked retinal vasculature alterations including neovascularization, ischemia, and disrupted blood–retinal barrier. The decreased visual function and retinal disruption reported earlier may reflect vasculopathy as well as neuropathy.

  8. Retinal atlas statistics from color fundus images

    Science.gov (United States)

    Lee, Sangyeol; Abramoff, Michael D.; Reinhardt, Joseph M.

    2010-03-01

    An atlas provides a reference anatomic structure and an associated coordinate system. An atlas may be used in a variety of applications, including segmentation and registration, and can be used to characterize anatomy across a population. We present a method for generating an atlas of the human retina from 500 color fundus image pairs. Using color fundus image pairs, we register image pairs to obtain a larger anatomic field of view. Key retinal anatomic features are selected for atlas landmarks: disk center, fovea, and main vessel arch. An atlas coordinate system is defined based on the statistics of the landmarks. Images from the population are warped into the atlas space to produce a statistical retinal atlas which can be used for automatic diagnosis, concise indexing, semantic blending, etc.

  9. Retinal Image Simulation of Subjective Refraction Techniques.

    Science.gov (United States)

    Perches, Sara; Collados, M Victoria; Ares, Jorge

    2016-01-01

    Refraction techniques make it possible to determine the most appropriate sphero-cylindrical lens prescription to achieve the best possible visual quality. Among these techniques, subjective refraction (i.e., patient's response-guided refraction) is the most commonly used approach. In this context, this paper's main goal is to present a simulation software that implements in a virtual manner various subjective-refraction techniques-including Jackson's Cross-Cylinder test (JCC)-relying all on the observation of computer-generated retinal images. This software has also been used to evaluate visual quality when the JCC test is performed in multifocal-contact-lens wearers. The results reveal this software's usefulness to simulate the retinal image quality that a particular visual compensation provides. Moreover, it can help to gain a deeper insight and to improve existing refraction techniques and it can be used for simulated training. PMID:26938648

  10. Retinal Image Simulation of Subjective Refraction Techniques

    Science.gov (United States)

    Perches, Sara; Collados, M. Victoria; Ares, Jorge

    2016-01-01

    Refraction techniques make it possible to determine the most appropriate sphero-cylindrical lens prescription to achieve the best possible visual quality. Among these techniques, subjective refraction (i.e., patient’s response-guided refraction) is the most commonly used approach. In this context, this paper’s main goal is to present a simulation software that implements in a virtual manner various subjective-refraction techniques—including Jackson’s Cross-Cylinder test (JCC)—relying all on the observation of computer-generated retinal images. This software has also been used to evaluate visual quality when the JCC test is performed in multifocal-contact-lens wearers. The results reveal this software’s usefulness to simulate the retinal image quality that a particular visual compensation provides. Moreover, it can help to gain a deeper insight and to improve existing refraction techniques and it can be used for simulated training. PMID:26938648

  11. Arterial waveform analysis.

    Science.gov (United States)

    Esper, Stephen A; Pinsky, Michael R

    2014-12-01

    The bedside measurement of continuous arterial pressure values from waveform analysis has been routinely available via indwelling arterial catheterization for >50 years. Invasive blood pressure monitoring has been utilized in critically ill patients, in both the operating room and critical care units, to facilitate rapid diagnoses of cardiovascular insufficiency and monitor response to treatments aimed at correcting abnormalities before the consequences of either hypo- or hypertension are seen. Minimally invasive techniques to estimate cardiac output (CO) have gained increased appeal. This has led to the increased interest in arterial waveform analysis to provide this important information, as it is measured continuously in many operating rooms and intensive care units. Arterial waveform analysis also allows for the calculation of many so-called derived parameters intrinsically created by this pulse pressure profile. These include estimates of left ventricular stroke volume (SV), CO, vascular resistance, and during positive-pressure breathing, SV variation, and pulse pressure variation. This article focuses on the principles of arterial waveform analysis and their determinants, components of the arterial system, and arterial pulse contour. It will also address the advantage of measuring real-time CO by the arterial waveform and the benefits to measuring SV variation. Arterial waveform analysis has gained a large interest in the overall assessment and management of the critically ill and those at a risk of hemodynamic deterioration. PMID:25480767

  12. Imaging the vertebral artery

    International Nuclear Information System (INIS)

    Although conventional intraarterial digital subtraction angiography remains the gold standard method for imaging the vertebral artery, noninvasive modalities such as ultrasound, multislice computed tomographic angiography and magnetic resonance angiography are constantly improving and are playing an increasingly important role in diagnosing vertebral artery pathology in clinical practice. This paper reviews the current state of vertebral artery imaging from an evidence-based perspective. Normal anatomy, normal variants and a number of pathological entities such as vertebral atherosclerosis, arterial dissection, arteriovenous fistula, subclavian steal syndrome and vertebrobasilar dolichoectasia are discussed. (orig.)

  13. Scleral buckling with a noncontact wide-angle viewing system in the management of retinal detachment with undetected retinal break: a case report

    OpenAIRE

    Kita M; Fujii Y; Kawagoe N; Hama S

    2013-01-01

    Mihori Kita, Yukiko Fujii, Naoaki Kawagoe, Sachiyo HamaDepartment of Ophthalmology, National Hospital Organization Kyoto Medical Center, Kyoto, JapanAbstract: A young patient who showed rhegmatogenous retinal detachment with preoperatively undetected retinal break was successfully treated by scleral buckling using a noncontact wide-angle viewing system.Keywords: retinal detachment, retinal breaks, scleral buckling, noncontact wide-angle viewing system

  14. Novel cell transplantation strategies for treatment of degenerative retinal disease.

    OpenAIRE

    Keegan, D. J.

    2005-01-01

    Retinal degenerations, both hereditary and acquired, are major causes of visual morbidity world-wide. Two of the principal disease categories are age-related macular degeneration (AMD) and retinitis pigmentosa (RP). AMD is the major cause of blind registrations in the over 65 age group in the western world and retinitis pigmentosa has an incidence of 1:3500 but, significantly, affects much younger patients. As yet there are no treatments available for these diseases that are either definitive...

  15. Scleral buckling for retinal detachment in patients with retinoblastoma

    International Nuclear Information System (INIS)

    Three children (two girls and one boy) with bilateral retinoblastoma each developed a presumed rhegmatogenous retinal detachment in one eye. All three eyes had previously received radiation and cryotherapy. In each case the retinal detachment responded promptly to conventional surgical methods via scleral buckling in the area of treated retinoblastoma and presumed retinal break. All three eyes have retained useful vision for follow-up periods of 3.5 to 12 years

  16. Bilateral retinal detachment in a case of Reiter's disease.

    OpenAIRE

    Belcon, M. C.; Bensen, W. G.; Zahoruk, R. M.

    1984-01-01

    A patient is described who developed co-existent Reiter's disease and bilateral non-traumatic retinal detachment. Although numerous ophthalmological disorders are associated with Reiter's disease and HLA-B27, to our knowledge this is the first report of co-existent retinal detachment. Although this relationship may be fortuitous, there are a number of immunological mechanisms common to both entities. Retinal detachment, unlike bilateral conjunctivitis and acute anterior uveitis, may be clinic...

  17. Guidelines for the management of rhegmatogenous retinal detachment

    OpenAIRE

    Das Taraprasad

    1993-01-01

    Current techniques of rhegmatogenous retinal detachment repair allow most detachments to be repaired successfully. The success of repair depends on a careful pre-operative examination and choice of an appropriate procedure. The surgery is usually tailored to individual needs. Improvements in surgical techniques coupled with a better understanding of the pathophysiology of rhegmatogenous retinal detachment continue to improve the anatomic and functional success of retinal detachment repair.

  18. Retinal detachment in identical twins with Stickler syndrome type 1.

    OpenAIRE

    Watanabe, Y.(Kanagawa University, Yokohama, 221-8686, Japan); Ueda, M.; Adachi-Usami, E

    1996-01-01

    BACKGROUND: The high incidence of retinal detachment and its poor surgical prognosis in patients with Stickler syndrome are well known. However, the vitreoretinal relation to retinal detachment in this syndrome is uncertain. METHODS: Vitreoretinal examination with a binocular indirect ophthalmoscope and a Goldmann three mirror contact lens was performed on identical twin boys with Stickler syndrome. Each had retinal detachment in the left eye, and many aspects of their fundus findings were si...

  19. Retinitis pigmentosa and congenital toxoplasmosis: A rare coexistence

    OpenAIRE

    Chhabra Manpreet; Prakash Gunjan; Vashisht Nagender; Garg S

    2007-01-01

    We describe a previously unreported co-existence of retinitis pigmentosa and congenital toxoplasmosis. An eight year old male presented to our center with complaints of decreased night vision. Fundus evaluations in both the eyes demonstrated features typical of retinitis pigmentosa. There were well-defined punched out healed chorio-retinal scars suggestive of congenital toxoplasmosis. On the basis of history, clinical findings and reduction of a and b wave amplitudes on scotopic and photopic ...

  20. [Photogenic retinal damage and its medicinal prevention: lipid peroxide studies].

    Science.gov (United States)

    Chen, W H; Zhang, H R

    1994-03-01

    Continuous illumination of 18,175 lx caused degeneration of the retinal photoreceptor cells in albino rats, accompanied by increase of malondialdehyde (MDA) 3 days after the light exposure. The MDA decreased gradually to return to normal 8 days after the exposure. Administration of vitamin E or beta-carotine both prevented the increase of retinal lipid peroxide with amelioration of the photic injury to the retinal structures, though the effects were closely related to the dosage and time of medication. PMID:8001445

  1. Taurine Provides Neuroprotection against Retinal Ganglion Cell Degeneration

    OpenAIRE

    Froger, Nicolas; Cadetti, Lucia; Lorach, Henri; Martins, Joao; Bemelmans, Alexis-Pierre; Dubus, Elisabeth; Degardin, Julie; Pain, Dorothée; Forster, Valérie; Chicaud, Laurent; Ivkovic, Ivana; Simonutti, Manuel; Fouquet, Stéphane; Jammoul, Firas; Léveillard, Thierry

    2012-01-01

    Retinal ganglion cell (RGC) degeneration occurs in numerous retinal diseases leading to blindness, either as a primary process like in glaucoma, or secondary to photoreceptor loss. However, no commercial drug is yet directly targeting RGCs for their neuroprotection. In the 70s, taurine, a small sulfonic acid provided by nutrition, was found to be essential for the survival of photoreceptors, but this dependence was not related to any retinal disease. More recently, taurine deprivation was inc...

  2. A novel method for blood vessel detection from retinal images

    OpenAIRE

    Luo Shuqian; Xu Lili

    2010-01-01

    Abstract Background The morphological changes of the retinal blood vessels in retinal images are important indicators for diseases like diabetes, hypertension and glaucoma. Thus the accurate segmentation of blood vessel is of diagnostic value. Methods In this paper, we present a novel method to segment retinal blood vessels to overcome the variations in contrast of large and thin vessels. This method uses adaptive local thresholding to produce a binary image then extract large connected compo...

  3. Inner retinal photoreception independent of the visual retinoid cycle

    OpenAIRE

    Tu, Daniel C.; Owens, Leah A.; Anderson, Lauren; Golczak, Marcin; Doyle, Susan E.; McCall, Maureen; Menaker, Michael; PALCZEWSKI, KRZYSZTOF; Van Gelder, Russell N.

    2006-01-01

    Mice lacking the visual cycle enzymes RPE65 or lecithin-retinol acyl transferase (Lrat) have pupillary light responses (PLR) that are less sensitive than those of mice with outer retinal degeneration (rd/rd or rdta). Inner retinal photoresponses are mediated by melanopsin-expressing, intrinsically photosensitive retinal ganglion cells (ipRGCs), suggesting that the melanopsin-dependent photocycle utilizes RPE65 and Lrat. To test this hypothesis, we generated rpe65?/?; rdta and lrat?/?; rd/rd m...

  4. Rpe65 as a modifier gene for inherited retinal degeneration

    OpenAIRE

    Samardzija, M; Wenzel, A.; Naash, M.; Remé, C. E.; Grimm, C.

    2006-01-01

    Light accelerates progression of retinal degeneration in many animal models of retinitis pigmentosa (RP). A sequence variant in the Rpe65 gene (Rpe65450Leu or Rpe65450Met) can act as a modulator of light-damage susceptibility in mice by influencing the kinetics of rhodopsin regeneration and thus by modulating the photon absorption. Depending on exposure duration and light intensity applied, white fluorescent light induces photoreceptor apoptosis and retinal degeneration in wild-type mice by t...

  5. Progressive Outer Retinal Necrosis and Immunosuppressive Therapy in Myasthenia Gravis

    OpenAIRE

    Coisy, Solène; Ebran, Jean-Marc; Milea, Dan

    2014-01-01

    Introduction Progressive outer retinal necrosis (PORN) is a rare but devastating infectious retinitis associated with varicella zoster virus (VZV) and responsible for severe visual loss. Case Report A 59-year-old man treated for generalized myasthenia with oral azathioprine and prednisone presented with severe unilateral necrotizing retinitis. Polymerase chain reaction of the aqueous and vitreous humors was diagnostic for VZV PORN. Conclusion VZV PORN is a severe potential ocular complication...

  6. Case of Bilateral Retinal Neovascularization Associated with Chronic Idiopathic Myelofibrosis

    OpenAIRE

    Kim, Moon Jung; Yu, Hyeong Gon

    2010-01-01

    We report a case of bilateral peripheral retinal neovascularization and chronic idiopathic myelofibrosis in a 69-year-old man. Ophthalmic examination revealed peripheral retinal nonperfusion with retinal neovascularization in both eyes and vitreous hemorrhage in the right eye. Fluorescein angiography of both eyes showed a marked midperipheral and peripheral avascular retina temporally with arteriovenous anastomosis and sea-fan neovascularizations. Blood tests showed pancytopenia and teardrop-...

  7. Detection of Pathological Lesions in High Resolution Retinal Images

    OpenAIRE

    Rosander, Frida

    2013-01-01

    High resolution retinal cameras with adaptive optics makes it possible to image small structures in the eye, such as photoreceptors and nerve bres, as well as blood vessels. Adaptive optics was rst developed to reduce blur in stellar images, but has later been used to correct for ocular aberrations in order to achieved higher resolution in retinal images. The development of these high resolution retinal cameras gives new pos- sibilities, and this master thesis has as purpose to investigate tw...

  8. Retinal Fundus Image Registration via Vascular Structure Graph Matching

    OpenAIRE

    Kexin Deng; Jie Tian; Jian Zheng; Xing Zhang; Xiaoqian Dai; Min Xu

    2010-01-01

    Motivated by the observation that a retinal fundus image may contain some unique geometric structures within its vascular trees which can be utilized for feature matching, in this paper, we proposed a graph-based registration framework called GM-ICP to align pairwise retinal images. First, the retinal vessels are automatically detected and represented as vascular structure graphs. A graph matching is then performed to find global correspondences between vascular bifurcations. Finally, a revis...

  9. Retinal oximeter for the blue-green oximetry technique

    OpenAIRE

    Denninghoff, Kurt R.; Sieluzycka, Katarzyna B.; Hendryx, Jennifer K.; Ririe, Tyson J.; DeLuca, Lawrence; Chipman, Russell A.

    2011-01-01

    Retinal oximetry offers potential for noninvasive assessment of central venous oxyhemoglobin saturation (SO2) via the retinal vessels but requires a calibrated accuracy of ±3% saturation in order to be clinically useful. Prior oximeter designs have been hampered by poor saturation calibration accuracy. We demonstrate that the blue-green oximetry (BGO) technique can provide accuracy within ±3% in swine when multiply scattered light from blood within a retinal vessel is isolated. A noninvasive ...

  10. The effect of retinal image slip on peripheral visual acuity

    OpenAIRE

    Macedo, António Filipe; Crossland, Michael; Rubin, G S

    2008-01-01

    Retinal image slip promoted by fixational eye movements prevents image fading in central vision. However, in the periphery a higher amount of movement is necessary to prevent this fading. We assessed the effect of different levels of retinal image slip in peripheral vision by measuring peripheral visual acuity (VA), with and without crowding, while modulating retinal image slip by using gaze-linked stimuli. Measurements were carried out at four isoeccentric positions at 5 and at 10 degrees ec...

  11. Identification of diabetic retinopathy stages in human retinal image

    OpenAIRE

    A.Alaimahal, Dr.S.Vasuki.

    2013-01-01

    A novel method to identify the Diabetic retinopathy stages in human retinal image is proposed. Diabetic retinopathy is the dangerous eye disease cause the blindness in worldwide. The first manifestation of diabetic retinopathy is microaneurysms. They are appearing as small reddish dot in human retinal image. The number of microaneurysms is the important parameter used to identify the severity of the diabetic retinopathy. Hence the detection of microaneurysms in human retinal image is the majo...

  12. Image Compression and Resizing for Retinal Implant in Bionic Eye

    OpenAIRE

    N.Sharmili; P. S. Ramaiah; G.Swamynadhan

    2011-01-01

    One field where computer-related Image processing technology shows great promise for the future isbionic implants such as Cochlear implants, Retinal implants etc.. Retinal implants are being developedaround the world in hopes of restoring useful vision for patients suffering from certain types of diseaseslike Age-related Macular Degeneration (AMD) and Retinitis Pigmentosa (RP). In these diseases thephotoreceptor cells slowly degenerated, leading to blindness. However, many of the inner retina...

  13. Stem cells in retinal regeneration: past, present and future

    OpenAIRE

    Ramsden, Conor M.; Powner, Michael B.; Carr, Amanda-Jayne F.; Smart, Matthew J. K.; da Cruz, Lyndon; Coffey, Peter J.

    2013-01-01

    Stem cell therapy for retinal disease is under way, and several clinical trials are currently recruiting. These trials use human embryonic, foetal and umbilical cord tissue-derived stem cells and bone marrow-derived stem cells to treat visual disorders such as age-related macular degeneration, Stargardt's disease and retinitis pigmentosa. Over a decade of analysing the developmental cues involved in retinal generation and stem cell biology, coupled with extensive surgical research, have yield...

  14. Avulsão vascular retiniana Avulsed retinal vessels

    Directory of Open Access Journals (Sweden)

    Leonardo Pérez Zeni

    2006-02-01

    Full Text Available OBJETIVO: Descrever a evolução de uma série de casos com avulsão vascular retiniana sem descolamento tratados pelo fotocoagulação ou introflexão escleral. MÉTODOS: Análise observacional retrospectiva. No período entre 2001-2003 foram tratados 13 olhos com avulsão sem descolamento utilizando-se o laser ou a introflexão escleral. O seguimento mínimo foi de 6 meses. Média etária de 53,6 anos. RESULTADOS: Oito olhos foram somente fotocoagulados e 5, submetidos a introflexão. O sintoma mais comum foi a baixa na acuidade visual. Em 7 olhos (53,8% a hemorragia vítrea em quantidade variável estava presente ao diagnóstico. Destes, 3 tiveram novo episódio após os procedimentos (42,8%. A acuidade visual final em todos os olhos foi igual ou melhor do que a inicial. Nenhuma complicação foi observada. CONCLUSÃO: Nesta série de casos com avulsão vascular sem descolamento houve evolução favorável, independente das técnicas utilizadas. A hemorragia vítrea tardia é a principal intercorrência tardia observada, mas não comprometeu os resultados.PURPOSE: To describe the clinical evolution of cases with avulsed retinal vessels without retinal detachment treated with laser or scleral buckle. METHODS: Retrospective analysis of cases with avulsed retinal vessels treated between 2001-2003. Laser photocoagulation or scleral buckle was used. The minimum follow-up was 6 months. Average age was 53.6 years. RESULTS: Of 13 patients, 8 were photoagulated with argon laser and 5 were submitted to a scleral buckle. The most common symptom was reduction in visual acuity. Vitreous hemorrhage was present in 7 eyes (53.8% at diagnosis, and was the most frequent complication after treatment (30.7%. Final visual acuity was unchanged. CONCLUSION: Avulsed retinal vessels have a good prognosis using laser or buckle. Late vitreous hemorrhage was the main complication.

  15. Retinitis Pigmentosa in Childhood: A Case Report

    Directory of Open Access Journals (Sweden)

    Erdal Eren

    2008-06-01

    Full Text Available Retinitis pigmentosa (RP is characterized by progressive loss of vision and accompanied by many syndromes. Therefore, early diagnosis is very important in RP. Now, definitive treatment of RP is not available. Diagnosis is performed with good medical history and ophthalmolojical examination. We present a patient with RP and describe diagnosis, treatment and approach to this disease. (Journal of Current Pediatrics 2008; 6: 43-6

  16. Dog models for blinding inherited retinal dystrophies.

    Science.gov (United States)

    Petersen-Jones, Simon M; Komáromy, András M

    2015-03-01

    Spontaneous canine models exist for several inherited retinal dystrophies. This review will summarize the models and indicate where they have been used in translational gene therapy trials. The RPE65 gene therapy trials to treat childhood blindness are a good example of how studies in dogs have contributed to therapy development. Outcomes in human clinical trials are compared and contrasted with the result of the preclinical dog trials. PMID:25671556

  17. Topography of retinal recovery processes in humans

    OpenAIRE

    Mazinani BE; Merx E; Plange N; Walter P; Roessler GF

    2014-01-01

    Babac E Mazinani, Elke Merx, Niklas Plange, Peter Walter, Gernot F RoesslerRWTH Aachen University, Aachen, GermanyBackground: The purpose of this study was to examine retinal recovery processes to­pographically by the application of three flash sequences with specific interstimulus intervals.Methods: Twelve healthy subjects underwent multifocal electroretinography with a light-emitting diode stimulator. Every flash sequence consisted of three flashes with 25 msec between the fir...

  18. Progesterone receptor signalling in retinal photoreceptor neuroprotection.

    Science.gov (United States)

    Wyse Jackson, Alice C; Roche, Sarah L; Byrne, Ashleigh M; Ruiz-Lopez, Ana M; Cotter, Thomas G

    2016-01-01

    'Norgestrel', a synthetic form of the female hormone progesterone has been identified as potential drug candidate for the treatment of the degenerative eye disease retinitis pigmentosa. However, to date, no work has looked at the compound's specific cellular target. Therefore, this study aimed to identify the receptor target of Norgestrel and begin to examine its potential mechanism of action in the retina. In this work, we identify and characterize the expression of progesterone receptors present in the C57 wild type and rd10 mouse model of retinitis pigmentosa. Classical progesterone receptors A and B (PR A/B), progesterone receptor membrane components 1 and 2 (PGRMC1, PGRMC2) and membrane progesterone receptors ?, ? and ? were found to be expressed. All receptors excluding PR A/B were also found in the 661W photoreceptor cell line. PGRMC1 is a key regulator of apoptosis and its expression is up-regulated in the degenerating rd10 mouse retina. Activated by Norgestrel through nuclear trafficking, siRNA knock down of PGRMC1 abrogated the protective properties of Norgestrel on damaged photoreceptors. Furthermore, specific inhibition of PGRMC1 by AG205 blocked Norgestrel-induced protection in stressed retinal explants. Therefore, we conclude that PGRMC1 is crucial to the neuroprotective effects of Norgestrel on stressed photoreceptors. The synthetic progestin 'Norgestrel' has been identified as a potential therapeutic for the treatment of Retinitis Pigmentosa, a degenerative eye disease. However, the mechanism behind this neuroprotection is currently unknown. In this work, we identify 'Progesterone Receptor Membrane Component 1' as the major progesterone receptor eliciting the protective effects of Norgestrel, both in vitro and ex vivo. This furthers our understanding of Norgestrel's molecular mechanism, which we hope will help bring Norgestrel one step closer to the clinic. PMID:26447367

  19. Bilateral acute retinal necrosis after herpetic meningitis

    OpenAIRE

    Katsura T; Hirota K; Akimoto M

    2012-01-01

    Keisho Hirota1,2, Masayuki Akimoto1,3, Toshiaki Katsura21Department of Ophthalmology, Kyoto Medical Center, National Hospital Organization, 2Internal Medicine, Kyoto Medical Center, 3Clinical Research Center, Kyoto Medical Center, Kyoto, JapanPurpose: The report of a case of bilateral acute retinal necrosis after herpetic meningitis.Case report: A 47-year-old man was admitted with the chief complaint of persistent high fever and transient loss of consciousness. Although his general condition ...

  20. Textural Measurements for Retinal Image Analysis

    OpenAIRE

    Mohammad, Suraya

    2015-01-01

    This thesis present research work conducted in the field of retina image analysis. More specifically, the work is directed at the application of texture analysis technique for the segmentation of common retinal landmark and for retina image classification. The main challenge in this research is in identifying the suitable texture measurement for retina images. In this research we proposed the used of texture measurement based on Binary Robust Independent Elementary Features (BRIEF). BRIEF mea...

  1. Normative Values of Retinal Oxygen Saturation in Rhesus Monkeys: The Beijing Intracranial and Intraocular Pressure (iCOP) Study

    Science.gov (United States)

    Li, Jing; Yang, Yiquan; Yang, Diya; Liu, Xiangxiang; Sun, Yunxiao; Wei, Shifei; Wang, Ningli

    2016-01-01

    Objective To study the normal values of the retinal oxygen saturation in Rhesus monkeys and to evaluated repeatability and reproducibility of retinal oxygen saturation measurements. Methods Eighteen adult Rhesus macaque monkeys were included in this experimental study. An Oxymap T1 retinal oximeter (Oxymap, Reykjavik, Iceland) was used to perform oximetry on all subjects. Global arterial (SaO2) and venous oxygen saturation (SvO2), arteriovenous difference in SO2 were measured. In the first examination, each eye was imaged three times. At the following two examinations, each eye was imaged once. All examinations were finished in one month. P values were calculated to evaluate the difference between the measurements during three visits by performing an ANOVA. Intra-visit and inter-visit intraclass correlation coefficient (ICC) was determined. Results At baseline, the average SaO2 and SvO2 were 89.48 ± 2.64% and 54.85 ± 2.18%, respectively. The global A-V difference was 34.63 ± 1.91%. The difference between the three visits was not significant (p>0.05). The highest A-V difference in SO2 and lowest saturations were found in the inferotemporal quadrant. Intra-session and inter-visit repeatability were both high. For all oxygen saturation parameters, the ICC values of the intra-session repeatability ranged between 0.92 and 0.96. As found previously, a relatively high ICC value for inter-visit repeatability also was found for all oxygen saturation measurements, ranging between 0.86 and 0.94, with the lowest values in the infero-nasal quadrant. Conclusions Our study is the first to describe retinal SO2 in healthy Rhesus monkeys. In normal monkey eyes, the reproducibility and repeatability of retinal oximetry oxygen saturation measurements were high in the retinal arterioles and venules. Our results support that Oxymap T1 retinal oximetry is a suitable and reliable technique in monkey studies. PMID:26930659

  2. Idiopathic juxtafoveolar retinal telangiectasis: A current review

    Directory of Open Access Journals (Sweden)

    Nowilaty Sawsan

    2010-01-01

    Full Text Available Idiopathic juxtafoveolar retinal telangiectasis (IJFT, also known as parafoveal telangiectasis or idiopathic macular telangiectasia, refers to a heterogeneous group of well-recognized clinical entities characterized by telangiectatic alterations of the juxtafoveolar capillary network of one or both eyes, but which differ in appearance, presumed pathogenesis, and management strategies. Classically, three groups of IJFT are identified. Group I is unilateral easily visible telangiectasis occurring predominantly in males, and causing visual loss as a result of macular edema. Group II, the most common, is bilateral occurring in both middle-aged men and women, and presenting with telangiectasis that is more difficult to detect on biomicroscopy, but with characteristic and diagnostic angiographic and optical coherence tomography features. Vision loss is due to retinal atrophy, not exudation, and subretinal neovascularization is common. Group III is very rare characterized predominantly by progressive obliteration of the perifoveal capillary network, occurring usually in association with a medical or neurologic disease. This paper presents a current review of juxtafoveolar retinal telangiectasis, reviewing the classification of these entities and focusing primarily on the two most common types encountered in clinical practice, i.e., groups I and II, describing their clinical features, histopathology, natural history, complications, latest results from imaging modalities and functional studies, differential diagnosis, and treatment modalities.

  3. Laser scleral buckling for retinal reattachment.

    Science.gov (United States)

    Ren, Q; Simon, G; Parel, J M; Smiddy, W

    1993-06-15

    The holmium:yttrium aluminum garnet (Ho:YAG) laser produces infrared light that is absorbed inside scleral tissues, which increases local temperature, thereby shrinking collagen and inducing a buckle effect. Scleral indentation was induced in ten cadaver eyes by shrinkage of scleral collagen fibers by using a pulsed solid-state Ho:YAG (2.1-microns) laser with fiberoptic delivery. The amount of laser-induced buckling effect is controlled by selecting laser treatment settings such as beam spot, radiant exposure, and number of pulses. With treatment using 11.3 +/- 1.2 J/cm2 of laser radiant exposure and five pulses, laser-induced scleral shrinkage affected only the external two thirds of the scleral tissue. No thermal damage or disruption was observed in subjacent retinal pigment epithelium, choroid, or retina. The coupling of two appropriately selected lasers may allow laser-induced scleral buckling and transscleral retinal photocoagulation by using the same laser probe for retinal reattachment. PMID:8506911

  4. Retinitis pigmentosa and ocular blood flow

    Directory of Open Access Journals (Sweden)

    Konieczka Katarzyna

    2012-12-01

    Full Text Available Abstract Is the concept of integrative, preventive and personalised medicine applicable to the relationship between retinitis pigmentosa (RP and ocular blood flow (OBF? RP encompasses a group of hereditary diseases of the posterior segment of the eye characterised by degeneration, atrophy and finally loss of photoreceptors and retinal pigment epithelium, leading to progressive visual loss. Many different mutations affecting different genes can lead to the clinical picture of RP. Even though the disease has a clear genetic background, there are obviously other factors influencing the manifestation and progression of RP. In this review, we focus on the role of OBF. There is evidence that, in PR patients, OBF is more reduced than one would expect secondary to the retinal atrophy. The main cause of this additional component seems to be primary vascular dysregulation (PVD syndrome. As PVD syndrome is partly treatable, a vascular evaluation of RP patients is meaningful. Based on the outcome, a targeted individualised, preventive or supportive treatment might be introduced in selected RP patients.

  5. Finite element modeling of retinal prosthesis mechanics.

    Science.gov (United States)

    Basinger, B C; Rowley, A P; Chen, K; Humayun, M S; Weiland, J D

    2009-10-01

    Epiretinal prostheses used to treat degenerative retina diseases apply stimulus via an electrode array fixed to the ganglion cell side of the retina. Mechanical pressure applied by these arrays to the retina, both during initial insertion and throughout chronic use, could cause sufficient retinal damage to reduce the device's effectiveness. In order to understand and minimize potential mechanical damage, we have used finite element analysis to model mechanical interactions between an electrode array and the retina in both acute and chronic loading configurations. Modeling indicates that an acute tacking force distributes stress primarily underneath the tack site and heel edge of the array, while more moderate chronic stresses are distributed more evenly underneath the array. Retinal damage in a canine model chronically implanted with a similar array occurred in correlating locations, and model predictions correlate well with benchtop eyewall compression tests. This model provides retinal prosthesis researchers with a tool to optimize the mechanical electrode array design, but the techniques used here represent a unique effort to combine a modifiable device and soft biological tissues in the same model and those techniques could be extended to other devices that come into mechanical contact with soft neural tissues. PMID:19721183

  6. Antisense Oligonucleotide Therapy for Inherited Retinal Dystrophies.

    Science.gov (United States)

    Gerard, Xavier; Garanto, Alejandro; Rozet, Jean-Michel; Collin, Rob W J

    2016-01-01

    Inherited retinal dystrophies (IRDs) are an extremely heterogeneous group of genetic diseases for which currently no effective treatment strategies exist. Over the last decade, significant progress has been made utilizing gene augmentation therapy for a few genetic subtypes of IRD, although several technical challenges so far prevent a broad clinical application of this approach for other forms of IRD. Many of the mutations leading to these retinal diseases affect pre-mRNA splicing of the mutated genes . Antisense oligonucleotide (AON)-mediated splice modulation appears to be a powerful approach to correct the consequences of such mutations at the pre-mRNA level , as demonstrated by promising results in clinical trials for several inherited disorders like Duchenne muscular dystrophy, hypercholesterolemia and various types of cancer. In this mini-review, we summarize ongoing pre-clinical research on AON-based therapy for a few genetic subtypes of IRD , speculate on other potential therapeutic targets, and discuss the opportunities and challenges that lie ahead to translate splice modulation therapy for retinal disorders to the clinic. PMID:26427454

  7. Gene therapy for inherited retinal degenerations.

    Science.gov (United States)

    Dalkara, Deniz; Sahel, José-Alain

    2014-03-01

    Gene therapy is quickly becoming a reality applicable in the clinic for inherited retinal diseases. Progress over the past decade has moved proof-of-concept gene therapies from bench to bedside. The remarkable success in safety and efficacy, in the phase I/II clinical trials for the form of the severe childhood-onset blindness, Leber's Congenital Amaurosis (LCA) type II (due to mutations in the RPE65 gene) generated significant interest and opened up possibilities for a new era of retinal gene therapies. Success in these clinical trials was due to combining the favorable features of both the retina as a target organ and adeno-associated virus (AAV) as a vector. The retina offers several advantages for gene therapy approaches. It is an anatomically defined structure that is readily accessible for therapy and has some degree of immune privilege, making it suitable for application of viral vectors. AAV, on the other hand, is a non-pathogenic helper dependent virus that has little immunogenicity. This viral vector transduces quiescent cells efficiently and thanks to its small size diffuses well in the interneural matrix, making it suitable for applications in neural tissue. Building on this initial clinical success with LCA II, we have now many opportunities to extend this proof-of-concept to other retinal diseases. This article will discuss what are some of the most imminent targets for such therapies and what are the challenges that we face in moving these therapies to the clinic. PMID:24702845

  8. Immunohistochemical and electrophysiological characterization of the mouse model for Retinitis Pigmentosa, rd10

    OpenAIRE

    Biswas, Sonia

    2014-01-01

    In the human disease retinitis pigmentosa (RP) the photoreceptors degenerate over time but the retinal network, in particular the retinal output neurons, the ganglion cells (RGCs) persist, providing a target for electrical stimulation by retinal prostheses. However, remodelling of the retinal network might interfere with this therapeutic approach. In the widely used mouse model of retinal degeneration, rd1, the loss of photoreceptors leads to rhythmic electrical activity of 10 to 16 Hz in the...

  9. Direct access to the middle meningeal artery for embolization of complex dural arteriovenous fistula: a hybrid treatment approach.

    Science.gov (United States)

    Lin, Ning; Brouillard, Adam M; Mokin, Maxim; Natarajan, Sabareesh K; Snyder, Kenneth V; Levy, Elad I; Siddiqui, Adnan H

    2015-07-01

    Endovascular embolization has become increasingly favored over microsurgical resection for treatment of complex dural arteriovenous fistulas (DAVFs). However, endovascular treatment can be restricted by tortuous transarterial access and a transvenous approach is not always feasible. We present a Borden III DAVF treated by direct access to the middle meningeal artery (MMA) and Onyx embolization performed in a hybrid operating room-angiography suite. A middle-aged patient with pulsatile headaches was found to have left transverse sinus occlusion and DAVF with retrograde cortical venous drainage fed by multiple external carotid artery (ECA) feeders. Endovascular attempts via conventional transvenous and transarterial routes were unsuccessful, and the major MMA feeder was accessed directly after temporal craniotomy was performed under neuronavigation. Onyx embolization was performed; complete occlusion of the fistula was achieved. Three-month follow-up angiography showed no residual filling; the patient remains complication-free. A combined surgical-endovascular technique in a hybrid operating room-angiography suite can be an effective treatment for DAVFs complicated by inaccessible arterial and transvenous approaches. PMID:24916414

  10. Blood-retinal barrier permeability versus diabetes duration and retinal morphology in insulin dependent diabetic patients

    DEFF Research Database (Denmark)

    Krogsaa, B; Lund-Andersen, H; Mehlsen, J; Sestoft, L

    1987-01-01

    the pattern. However, the pathologically increased permeability after ten years duration of the disease could not be demonstrated in diabetics with onset of the disease after the age of 30 years. The permeability of the blood-retinal barrier correlated well with changes in retinal morphology as seen......The blood-retinal barrier permeability to fluorescein was quantitated in 54 patients (22 females and 32 males) with insulin dependent diabetes mellitus (IDDM) of different duration. Correlation was demonstrated between permeability and diabetes duration. A normal permeability was measured in...... patients with up to ten years diabetes duration. A pathologically increased permeability was measured with ten to 15 years diabetes duration and during the next decade the permeability increased rapidly to 5-10 times the normal value. Onset of diabetes in the decade before and after puberty did not change...

  11. [An update on the treatment of central retinal vein thrombosis (retinal vein occlusion)].

    Science.gov (United States)

    Iord?nescu, C; Jurja, S

    2000-01-01

    The paper reviews the actual therapeutical means in a severe invalid eye disease. The treatment is not able to improve the retinal blood flow, being more effective on the main symptoms and complications. The isovolumetric hemodilution method as an up-to-date method in the treatment of central retinal vein occlusion, appears to bring better recuperation hopes, by a higher improvement of the local anatomical and hemodynamical factors. That is the reason why we shall expose it widely in our paper. Unfortunately, despite its complexity, the treatment of central retinal vein occlusion is not satisfactory from the point of view of the high number of patients that remain with a low visual acuity. The main goal of the therapy is the recovery of visual function, but a few aspects and especially the late presentation for ophthalmological examination, reduce the objective of treatment to prevent complications. PMID:11021101

  12. Hemorrhagic retinal macrocysts, simulating choroidal melanoma: a case report

    Directory of Open Access Journals (Sweden)

    Mansour AM

    2013-05-01

    Full Text Available Ahmad M Mansour,1 Mahmoud O Jaroudi21Department of Ophthalmology, American University of Beirut, Beirut, Lebanon; 2Department of Ophthalmology, Rafic Hariri University Hospital, Beirut, LebanonIntroduction: Hemorrhagic retinal macrocysts are extremely rare retinal lesions that can be mistaken for malignancy with subsequent enucleation. Such a case was diagnosed, by a retina specialist based on ultrasonography, as a choroidal melanoma with exudative retinal detachment and the patient was advised to have brachytherapy.Case presentation: A 15-year-old Caucasian boy suffered sudden visual loss in the left eye and exam revealed vitreous hemorrhage. Magnetic resonance imaging revealed the mass as hyperintense on T1-weighted images and isointense on T2-weighted images with no enhancement after gadolinium dye. Following scleral buckle, the hemorrhagic retinal macrocyst collapsed gradually over a period of 5 weeks. The patient recovered visual acuity of 6/7.5 at the 1-year follow up.Conclusion: A hemorrhagic retinal macrocyst can be erroneously diagnosed as choroidal melanoma. Hints for the presence of retinal macrocysts include: egg shape; cyst wall configuration; no attachment to the choroid; and presence of retinal detachment.Keywords: choroidal melanoma, retinal macrocyst, retinal detachment

  13. Risk of Retinal Detachment After Pediatric Cataract Surgery

    DEFF Research Database (Denmark)

    Haargaard, Birgitte; Andersen, Elisabeth W

    2014-01-01

    PURPOSE: To determine the long-term risk of retinal detachment following pediatric cataract surgery and to identify risk factors for retinal detachment. METHODS: We included all children (aged 0 to 17 years) who during the time period of 1977 to 2005 underwent pediatric cataract surgery in Denmark, excluding cataract cases caused by trauma, or acquired systemic or acquired ocular pathology, and cases with ocular anomalies associated with the development of retinal detachment. Cases of cataract were ascertained from the mandatory Danish National Patient Register, and information on retinal detachment was based on medical chart review. RESULTS: Among 1043 eyes of 656 children undergoing surgery for pediatric cataract, 25 eyes (23 children) developed retinal detachment at a median time of 9.1 years after surgery. The overall 20-year risk of retinal detachment was 7% (95% confidence interval [CI]: 3%-11%) among cataract patients. In otherwise normal children having isolated cataract, the risk was 3% (95% CI: 0%-7%). A significantly higher risk of developing retinal detachment was found in children with mental retardation (23% [95% CI: 9%-35%]) or in cataract cases with other ocular or systemic anomalies (16% [95% CI: 6%-24%]). CONCLUSIONS: The estimated overall risk of retinal detachment 20 years after pediatric cataract surgery was 7%, but only 3% for isolated cataract. Particularly high risks of retinal detachment after cataract surgery were associated with mental retardation and having other ocular or systemic diseases.

  14. Risk of retinal detachment after pediatric cataract surgery

    DEFF Research Database (Denmark)

    Haargaard, Birgitte; Andersen, Elisabeth W

    2014-01-01

    PURPOSE: To determine the long-term risk of retinal detachment following pediatric cataract surgery and to identify risk factors for retinal detachment. METHODS: We included all children (aged 0 to 17 years) who during the time period of 1977 to 2005 underwent pediatric cataract surgery in Denmark, excluding cataract cases caused by trauma, or acquired systemic or acquired ocular pathology, and cases with ocular anomalies associated with the development of retinal detachment. Cases of cataract were ascertained from the mandatory Danish National Patient Register, and information on retinal detachment was based on medical chart review. RESULTS: Among 1043 eyes of 656 children undergoing surgery for pediatric cataract, 25 eyes (23 children) developed retinal detachment at a median time of 9.1 years after surgery. The overall 20-year risk of retinal detachment was 7% (95% confidence interval [CI]: 3%-11%) among cataract patients. In otherwise normal children having isolated cataract, the risk was 3% (95% CI: 0%-7%). A significantly higher risk of developing retinal detachment was found in children with mental retardation (23% [95% CI: 9%-35%]) or in cataract cases with other ocular or systemic anomalies (16% [95% CI: 6%-24%]). CONCLUSIONS: The estimated overall risk of retinal detachment 20 years after pediatric cataract surgery was 7%, but only 3% for isolated cataract. Particularly high risks of retinal detachment after cataract surgery were associated with mental retardation and having other ocular or systemic diseases.

  15. Genetic determinants of hyaloid and retinal vasculature in zebrafish

    Directory of Open Access Journals (Sweden)

    Hyde David R

    2007-10-01

    Full Text Available Abstract Background The retinal vasculature is a capillary network of blood vessels that nourishes the inner retina of most mammals. Developmental abnormalities or microvascular complications in the retinal vasculature result in severe human eye diseases that lead to blindness. To exploit the advantages of zebrafish for genetic, developmental and pharmacological studies of retinal vasculature, we characterised the intraocular vasculature in zebrafish. Results We show a detailed morphological and developmental analysis of the retinal blood supply in zebrafish. Similar to the transient hyaloid vasculature in mammalian embryos, vessels are first found attached to the zebrafish lens at 2.5 days post fertilisation. These vessels progressively lose contact with the lens and by 30 days post fertilisation adhere to the inner limiting membrane of the juvenile retina. Ultrastructure analysis shows these vessels to exhibit distinctive hallmarks of mammalian retinal vasculature. For example, smooth muscle actin-expressing pericytes are ensheathed by the basal lamina of the blood vessel, and vesicle vacuolar organelles (VVO, subcellular mediators of vessel-retinal nourishment, are present. Finally, we identify 9 genes with cell membrane, extracellular matrix and unknown identity that are necessary for zebrafish hyaloid and retinal vasculature development. Conclusion Zebrafish have a retinal blood supply with a characteristic developmental and adult morphology. Abnormalities of these intraocular vessels are easily observed, enabling application of genetic and chemical approaches in zebrafish to identify molecular regulators of hyaloid and retinal vasculature in development and disease.

  16. Retinal detachment secondary to ocular perforation during retrobulbar Anaesthesia

    Directory of Open Access Journals (Sweden)

    Gopal Lingam

    1995-01-01

    Full Text Available The clinical characteristics and the retinal breaks associated with rhegmatogenous retinal detachments secondary to accidental globe perforation during local infiltration anaesthesia in five highly myopic eyes are presented. Retinal detachment was total with variable proliferative vitreoretinopathy. The pattern of retinal breaks was rather typical and predictable. Management involved vitreous surgery with internal tamponade by silicone oil in four eyes and perfluoropropane gas in one eye. At the last follow-up, all eyes had attached retina. One eye did not recover useful vision due to possible concurrent optic nerve damage.

  17. Performance Analysis of Retinal Image Blood Vessel Segmentation

    Directory of Open Access Journals (Sweden)

    D.Siva Sundhara Raja

    2014-06-01

    Full Text Available The retinal image diagnosis is an important methodology for diabetic retinopathy detection and analysis. in this paper, the morphological operations and svm classifier are used to detect and segment the blood vessels from the retinal image. the proposed system consists of three stages-first is preprocessing of retinal image to separate the green channel and second stage is retinal image enhancement and third stage is blood vessel segmentation using morphological operations and svm classifier. the performance of the proposed system is analyzed using publicly available dataset.

  18. Color Doppler Indices of Orbital Arterial Flow in End-Stage Renal Disease Patients; Are the Changes Related to Chronic Hemodialysis or Chronic Renal Failure?

    International Nuclear Information System (INIS)

    Endothelial injury is a well-known complication in chronic kidney disease (CKD) and hemodialysis. One of the sites in which early vascular changes may be detected is the retina. Of course, these flow changes may not be detected in ophthalmologic exams, but it seems that color Doppler sonography of retinal arteries may be helpful in these cases. In previous studies on CKD patients who underwent chronic hemodialysis,hemodynamic changes were noted in retinal arteries, but no study has been performed to determine which of the two processes (CKD or chronic hemodialysis) can produce these changes. In this study, we tried to answer this question. Doppler ultrasonography of the orbital vasculature including the ophthalmic artery and the central retinal artery was carried out in 17 patients (34 eyes) with chronic renal failure (CRF) who underwent hemodialysis, 17 patients (34 eyes)with CRF without a history of hemodialysis and 17 normal patients (34 eyes). The peak systolic velocity (PSV), end diastolic velocity (EDV) and resistance index were measured excluding hypertensive, diabetic patients and patients with cardiovascular disease. The mean PSV and EDV were lower only in the ophthalmic artery of CRF patients irrespective of the history of hemodialysis (PSV was 35.2 in hemodialysis, 38.8 in CRF and 51.6 in normal patients, P value = 0.001 and EDV was 7.4, 9.4, 11.8, respectively, P value =0.001) with no significant difference in the resistance index of the ophthalmic artery and other parameters [EDV, PSV, Resistance Index (RI)] in the central retinal artery. The mean PSV and DSV in the ophthalmic artery were lower only in the ophthalmic artery of CRF patients regardless of the history of hemodialysis. No significant difference in the resistance index of the ophthalmic artery and other parameters (EDV, PSV) of the central retinal artery were noted between different groups. These findings suggest that microvascular disease and endothelial cell dysfunction of the orbital vasculature are related to CRF and not to chronic hemodialysis

  19. Color Doppler Indices of Orbital Arterial Flow in End-Stage Renal Disease Patients; Are the Changes Related to Chronic Hemodialysis or Chronic Renal Failure?

    Directory of Open Access Journals (Sweden)

    Hadi Rokni Yazdi

    2012-03-01

    Full Text Available Background: Endothelial injury is a well-known complication in chronic kidney disease (CKD and hemodialysis. One of the sites in which early vascular changes may be detected is the retina. Of course, these flow changes may not be detected in ophthalmologic exams, but it seems that color Doppler sonography of retinal arteries may be helpful in these cases.Objectives: In previous studies on CKD patients who underwent chronic hemodialysis, hemodynamic changes were noted in retinal arteries, but no study has been performed to determine which of the two processes (CKD or chronic hemodialysis can produce these changes. In this study, we tried to answer this question.Patients and Methods: Doppler ultrasonography of the orbital vasculature including the ophthalmic artery and the central retinal artery was carried out in 17 patients (34 eyes with chronic renal failure (CRF who underwent hemodialysis, 17 patients (34 eyes with CRF without a history of hemodialysis and 17 normal patients (34 eyes. The peak systolic velocity (PSV, end diastolic velocity (EDV and resistance index were measured excluding hypertensive, diabetic patients and patients with cardiovascular disease.Results: The mean PSV and EDV were lower only in the ophthalmic artery of CRF patients irrespective of the history of hemodialysis (PSV was 35.2 in hemodialysis, 38.8 in CRF and 51.6 in normal patients, P value = 0.001 and EDV was 7.4, 9.4, 11.8, respectively, P value = 0.001 with no significant difference in the resistance index of the ophthalmic artery and other parameters [EDV, PSV, Resistance Index (RI] in the central retinal artery.Conclusions: The mean PSV and DSV in the ophthalmic artery were lower only in the ophthalmic artery of CRF patients regardless of the history of hemodialysis. No significant difference in the resistance index of the ophthalmic artery and other parameters (EDV, PSV of the central retinal artery were noted between different groups.These findings suggest that microvascular disease and endothelial cell dysfunction of the orbital vasculature are related to CRF and not to chronic hemodialysis.

  20. Transplantation of retinal pigment epithelial cells - a possible future treatment for age-related macular degeneration

    DEFF Research Database (Denmark)

    Wiencke, Anne Katrine

    2001-01-01

    ophthalmology, age-related macular degeneration, retinal pigment epithelial cells, transplantation, treatment......ophthalmology, age-related macular degeneration, retinal pigment epithelial cells, transplantation, treatment...

  1. Transplantation of retinal pigment epithelial cells - a possible future treatment for age-related macular degeneration

    DEFF Research Database (Denmark)

    Wiencke, Anne Katrine

    ophthalmology, age-related macular degeneration, transplantation, retinal pigment epithelial cells, treatment......ophthalmology, age-related macular degeneration, transplantation, retinal pigment epithelial cells, treatment...

  2. The all-trans-retinal dimer series of lipofuscin pigments in retinal pigment epithelial cells in a recessive Stargardt disease model

    OpenAIRE

    Kim, So R.; Jang, Young P.; Jockusch, Steffen; Fishkin, Nathan E.; Turro, Nicholas J.; Sparrow, Janet R.

    2007-01-01

    The bis-retinoid pigments that accumulate in retinal pigment epithelial cells as lipofuscin are associated with inherited and age-related retinal disease. In addition to A2E and related cis isomers, we previously showed that condensation of two molecules of all-trans-retinal leads to the formation of a protonated Schiff base conjugate, all-trans-retinal dimer-phosphatidylethanolamine. Here we report the characterization of the related pigments, all-trans-retinal dimer-ethanolamine and unconju...

  3. BILATERAL DUPLICATION OF RENAL ARTERIES

    OpenAIRE

    Prajkta A Thete; Mehera Bhoir; M. V. Ambiye

    2014-01-01

    Routine dissection of a male cadaver revealed the presence of bilateral double renal arteries. On the right side the accessory renal artery originated from the abdominal aorta just above the main renal artery. On the left side the accessory renal artery originated from the abdominal aorta about 1 cm above the main renal artery. Knowledge of the variations of renal vascular anatomy has importance in exploration and treatment of renal trauma, renal transplantation, renal artery embolization, su...

  4. Coronary Artery Bypass

    Science.gov (United States)

    ... Revascularization Valve Repair or Replacement Vascular Access for Hemodialysis Ventricular Assist Devices Coronary Artery Bypass | Share Bypass surgery is the most common type of heart surgery with more than 500,000 procedures performed each year in the United States. Arteries ...

  5. Heritability of cilioretinal arteries

    DEFF Research Database (Denmark)

    Taarnhøj, Nina Charlotte; Munch, Inger C; Kyvik, Kirsten O; Sander, Birgit; Kessel, Line; Sørensen, Thorkild I A; Hougaard, Jesper L; Larsen, Michael

    2005-01-01

    healthy monozygotic and dizygotic twins were examined using digital fundus photography and visual assessment of grayscale fundus photographs and color transparencies to detect the presence of cilioretinal arteries. RESULTS: Cilioretinal arteries were present in 45.1% of participants and 28.8% of eyes. The...

  6. Agujero retiniano en polo posterior secundario a un foco de retinitis por cándida / Posterior retinal hole secondary to a candida retinitis

    Scientific Electronic Library Online (English)

    ML, Álvarez-Suárez; L, Sánchez-Tabar; MJ, Viescas-Fernández; MA, Fernández-Álavarez.

    2005-07-01

    Full Text Available Caso Clínico: Varón de 36 años, heroinómano y HIV negativo, que presenta en su ojo izquierdo una lesión focal de retinitis candidiásica en polo posterior acompañada de iritis moderada y vitritis leve. El tratamiento con fluconazol provocó una buena cicatrización del foco retiniano y desaparición de [...] la vitritis pero dejó una tracción vítrea sobre el foco retiniano con una contracción de la membrana limitante interna macular. A los 2 años la tracción vítrea acabó produciendo un agujero retiniano que precisó fotocoagulación con láser de argón. Discusión: Los focos de retinitis por cándida pueden producir en su evolución agujeros retinianos por la fibrosis y tracción vítrea sobre la propia lesión retiniana. Abstract in english Case report: We describe the case of a 36-year-old man with a history of intravenous heroin use, who was HIV negative. Left ocular examination disclosed a focal candida retinitis in the posterior pole associated with vitritis and moderate iritis. Treatment with fluconazole inactived the chorio-retin [...] al lesion and resolved the vitritis, but developed an inner limiting membrane contraction over the macula. Two years later, vitreous traction produced a retinal hole that needed argon laser photocoagulation. Discussion: Candida retinitis which penetrates into the vitreous cavity can produce retinal holes by vitreous traction over the lesion.

  7. KNOWN RISK FACTORS FOR RETINAL VEIN OCCLUSION: ITS DISTRIBUTION AMONG OUR COMMUNITY - IUMSHS (1999-2000

    Directory of Open Access Journals (Sweden)

    M.H EMAMI

    2001-09-01

    Full Text Available Introduction. Retinal vein occlusion (RVO may lead to visual loss or even to blindness. RVO may accompany with most of systemic disease as well as some eye diseases. Since no effective treatment is known to restore the full vision in none of the cases, it is necessary to determine and identify the precipitating factors and to treat them in order to prevent the involvement of another eye. Methods. Among 2500 patients with chief complaint of visual loss 62 patients had retinal vessel occlusion, 59 patients (95 percent had RVO and 3 patients (5 percent had retinal artery occlusion (RAO. 3 patients with CRVO who didn"t fallow up were excluded the study. The necessary medical examinations were done in internal medicine clinic after primary examination in ophtalmology clinic and raw data were recorded in special form for each patient. Results. From 56 patients with RVO, 55.36 percent (31 subjects were female and 44.64 percent (25 subjects were male. 76.79 percent of patients (43 subjects were 50 years or more and 66.1 percent (37 subjects suffered from hypertension, 35.7 percent ( 20 subjects had hypercholestrolemia ; and 21.4 percent (12 patients had diabetes mellitus. 23.2 percent of patients (13 subjects were previously smokers, 14.28 percent (8 subjects were current smokers and the rest had quitted smoking. Totally, 37.5 percent of patients were menopausal women. In 57.14 percent of the patients body mass index BMI were higher than 24.9 Kg/m2.In 80.4 percent and 44.6 percent of the patients serum a2- globulin and ? globulion was higher than normal, respectively. Discussion. The data showed that most of the patients with RVO were more than 50 years old. Associated systemic risk factors in this study are listed bellow from the most to the least frequency order: hypertension, high 8MI, LDL hypercholestrolemia, diabetes mellitus and smoking.

  8. A novel transgenic zebrafish model for blood-brain and blood-retinal barrier development

    Directory of Open Access Journals (Sweden)

    Sugimoto Masahiko

    2010-07-01

    Full Text Available Abstract Background Development and maintenance of the blood-brain and blood-retinal barrier is critical for the homeostasis of brain and retinal tissue. Despite decades of research our knowledge of the formation and maintenance of the blood-brain (BBB and blood-retinal (BRB barrier is very limited. We have established an in vivo model to study the development and maintenance of these barriers by generating a transgenic zebrafish line that expresses a vitamin D-binding protein fused with enhanced green fluorescent protein (DBP-EGFP in blood plasma, as an endogenous tracer. Results The temporal establishment of the BBB and BRB was examined using this transgenic line and the results were compared with that obtained by injection of fluorescent dyes into the sinus venosus of embryos at various stages of development. We also examined the expression of claudin-5, a component of tight junctions during the first 4 days of development. We observed that the BBB of zebrafish starts to develop by 3 dpf, with expression of claudin-5 in the central arteries preceding it at 2 dpf. The hyaloid vasculature in the zebrafish retina develops a barrier function at 3 dpf, which endows the zebrafish with unique advantages for studying the BRB. Conclusion Zebrafish embryos develop BBB and BRB function simultaneously by 3 dpf, which is regulated by tight junction proteins. The Tg(l-fabp:DBP-EGFP zebrafish will have great advantages in studying development and maintenance of the blood-neural barrier, which is a new application for the widely used vertebrate model.

  9. Flux, not retinal illumination, is what cat retinal ganglion cells really care about.

    Science.gov (United States)

    Enroth-Cugell, C; Shapley, R M

    1973-09-01

    1. Evidence was obtained that the impulse/quantum (I/Q) ratio of the central response mechanism of retinal ganglion cells in the cat is controlled by the steady effective retinal flux of the background.2. One experiment revealed that the I/Q ratio was decreased as the area of an adapting spot, of constant illumination, was increased. The curve relating the I/Q ratio to background flux was the same regardless of the size of the adapting spot.3. The effective central summing area of many retinal ganglion cells was determined. For the same cells, the transition level (Enroth-Cugell & Shapley, 1973) of the impulse/quantum curve was also measured. Diffuse illumination at the transition level was inversely proportional to the effective summing area, when variation in dark-adapted sensitivity between cells was taken into account.4. Therefore, retinal ganglion cells with large central summing areas are more light-adapted by any given diffuse background than cells with small centres. PMID:4747230

  10. Detection of retinal nerve fiber layer defects in retinal fundus images using Gabor filtering

    Science.gov (United States)

    Hayashi, Yoshinori; Nakagawa, Toshiaki; Hatanaka, Yuji; Aoyama, Akira; Kakogawa, Masakatsu; Hara, Takeshi; Fujita, Hiroshi; Yamamoto, Tetsuya

    2007-03-01

    Retinal nerve fiber layer defect (NFLD) is one of the most important findings for the diagnosis of glaucoma reported by ophthalmologists. However, such changes could be overlooked, especially in mass screenings, because ophthalmologists have limited time to search for a number of different changes for the diagnosis of various diseases such as diabetes, hypertension and glaucoma. Therefore, the use of a computer-aided detection (CAD) system can improve the results of diagnosis. In this work, a technique for the detection of NFLDs in retinal fundus images is proposed. In the preprocessing step, blood vessels are "erased" from the original retinal fundus image by using morphological filtering. The preprocessed image is then transformed into a rectangular array. NFLD regions are observed as vertical dark bands in the transformed image. Gabor filtering is then applied to enhance the vertical dark bands. False positives (FPs) are reduced by a rule-based method which uses the information of the location and the width of each candidate region. The detected regions are back-transformed into the original configuration. In this preliminary study, 71% of NFLD regions are detected with average number of FPs of 3.2 per image. In conclusion, we have developed a technique for the detection of NFLDs in retinal fundus images. Promising results have been obtained in this initial study.

  11. Retinal Hemorrhages in 4 Patients with Dengue Fever

    OpenAIRE

    Chlebicki, Maciej Piotr; Ang, Brenda; Barkham, Timothy; Laude, Augustinus

    2005-01-01

    We report 4 patients with retinal hemorrhages that developed during hospitalization for dengue fever. Onset of symptoms coincided with resolution of fever and the nadir of thrombocytopenia. Retinal hemorrhages may reflect the rising incidence of dengue in Singapore or may be caused by changes in the predominant serotype of the dengue virus.

  12. A Qualitative Self-Study of Retinitis Pigmentosa

    Science.gov (United States)

    Fourie, Robert James

    2007-01-01

    Retinitis Pigmentosa (RP) is a retinal degenerative disease causing progressive blindness. Most research on RP is biomedical, and mostly from an observer perspective, therefore poorly reflecting the lived experience of having RP. Accordingly, the researcher conducted a retrospective qualitative self-study, to analyze reflections on his own…

  13. Retinal Remodeling: Concerns, Emerging Remedies and Future Prospects

    Science.gov (United States)

    Krishnamoorthy, Vidhyasankar; Cherukuri, Pitchaiah; Poria, Deepak; Goel, Manvi; Dagar, Sushma; Dhingra, Narender K.

    2016-01-01

    Deafferentation results not only in sensory loss, but also in a variety of alterations in the postsynaptic circuitry. These alterations may have detrimental impact on potential treatment strategies. Progressive loss of photoreceptors in retinal degenerative diseases, such as retinitis pigmentosa and age-related macular degeneration, leads to several changes in the remnant retinal circuitry. Müller glial cells undergo hypertrophy and form a glial seal. The second- and third-order retinal neurons undergo morphological, biochemical and physiological alterations. A result of these alterations is that retinal ganglion cells (RGCs), the output neurons of the retina, become hyperactive and exhibit spontaneous, oscillatory bursts of spikes. This aberrant electrical activity degrades the signal-to-noise ratio in RGC responses, and thus the quality of information they transmit to the brain. These changes in the remnant retina, collectively termed “retinal remodeling”, pose challenges for genetic, cellular and bionic approaches to restore vision. It is therefore crucial to understand the nature of retinal remodeling, how it affects the ability of remnant retina to respond to novel therapeutic strategies, and how to ameliorate its effects. In this article, we discuss these topics, and suggest that the pathological state of the retinal output following photoreceptor loss is reversible, and therefore, amenable to restorative strategies. PMID:26924962

  14. Quantification of retinal tangential movement in epiretinal membranes

    DEFF Research Database (Denmark)

    Kofod, Mads; la Cour, Morten

    2012-01-01

    To describe a technique of quantifying retinal vessel movement in eyes with epiretinal membrane (ERM) and correlate the retinal vessel movement with changes in best-corrected visual acuity (BCVA), central macular thickness (CMT), and patients' subjective reports about experienced symptoms (symptoms).

  15. Foscarnet as treatment for cytomegalovirus retinitis following bone marrow transplantation.

    OpenAIRE

    Ganly, P. S.; Arthur, C.; Goldman, J. M.; Schulenburg, W. E.

    1988-01-01

    This report describes a patient with chronic granulocytic leukaemia who developed cataracts on busulphan treatment. Following allogeneic bone marrow transplantation, he developed cytomegalovirus retinitis, which was treated successfully with trisodium phosphonoformate (foscarnet). Cytomegalovirus retinitis and its therapy, and busulphan-induced cataract are discussed.

  16. Risk of Retinal Detachment After Pediatric Cataract Surgery

    DEFF Research Database (Denmark)

    Haargaard, Birgitte; Andersen, Elisabeth W; Oudin, Anna; Poulsen, Gry; Wohlfahrt, Jan; la Cour, Morten; Melbye, Mads

    2014-01-01

    was based on medical chart review. RESULTS: Among 1043 eyes of 656 children undergoing surgery for pediatric cataract, 25 eyes (23 children) developed retinal detachment at a median time of 9.1 years after surgery. The overall 20-year risk of retinal detachment was 7% (95% confidence interval [CI]: 3...

  17. Growth of cultured porcine retinal pigment epithelial cells

    DEFF Research Database (Denmark)

    Wiencke, A.K.; Kiilgaard, Jens Folke; Nicolini, Jair; Bundgaard, Magnus; Röpke, Carsten; Dornonville De La Cour, Morten

    2003-01-01

    To establish and characterize cultures of porcine retinal pigment epithelial (pRPE) cells in order to produce confluent monolayers of cells for transplantation.......To establish and characterize cultures of porcine retinal pigment epithelial (pRPE) cells in order to produce confluent monolayers of cells for transplantation....

  18. Retinal progenitor cell xenografts to the pig retina

    DEFF Research Database (Denmark)

    Warfvinge, Karin; Kiilgaard, Jens Folke; Lavik, Erin B; Scherfig, Erik; Langer, Robert; Klassen, Henry J; Young, Michael J

    2005-01-01

    To investigate the survival, integration, and differentiation of mouse retinal progenitor cells after transplantation to the subretinal space of adult pigs.......To investigate the survival, integration, and differentiation of mouse retinal progenitor cells after transplantation to the subretinal space of adult pigs....

  19. Automated retinal fovea type distinction in spectral-domain optical coherence tomography of retinal vein occlusion

    Science.gov (United States)

    Wu, Jing; Waldstein, Sebastian M.; Gerendas, Bianca S.; Langs, Georg; Simader, Christian; Schmidt-Erfurth, Ursula

    2015-03-01

    Spectral-domain Optical Coherence Tomography (SD-OCT) is a non-invasive modality for acquiring high- resolution, three-dimensional (3D) cross-sectional volumetric images of the retina and the subretinal layers. SD-OCT also allows the detailed imaging of retinal pathology, aiding clinicians in the diagnosis of sight degrading diseases such as age-related macular degeneration (AMD), glaucoma and retinal vein occlusion (RVO). Disease diagnosis, assessment, and treatment will require a patient to undergo multiple OCT scans, possibly using multiple scanners, to accurately and precisely gauge disease activity, progression and treatment success. However, cross-vendor imaging and patient movement may result in poor scan spatial correlation potentially leading to incorrect diagnosis or treatment analysis. The retinal fovea is the location of the highest visual acuity and is present in all patients, thus it is critical to vision and highly suitable for use as a primary landmark for cross-vendor/cross-patient registration for precise comparison of disease states. However, the location of the fovea in diseased eyes is extremely challenging to locate due to varying appearance and the presence of retinal layer destroying pathology. Thus categorising and detecting the fovea type is an important prior stage to automatically computing the fovea position. Presented here is an automated cross-vendor method for fovea distinction in 3D SD-OCT scans of patients suffering from RVO, categorising scans into three distinct types. OCT scans are preprocessed by motion correction and noise filing followed by segmentation using a kernel graph-cut approach. A statistically derived mask is applied to the resulting scan creating an ROI around the probable fovea location from which the uppermost retinal surface is delineated. For a normal appearance retina, minimisation to zero thickness is computed using the top two retinal surfaces. 3D local minima detection and layer thickness analysis are used to differentiate between the remaining two fovea types. Validation employs ground truth fovea types identified by clinical experts at the Vienna Reading Center (VRC). The results presented here are intended to show the feasibility of this method for the accurate and reproducible distinction of retinal fovea types from multiple vendor 3D SD-OCT scans of patients suffering from RVO, and for use in fovea position detection systems as a landmark for intra- and cross-vendor 3D OCT registration.

  20. A Rare Coronary Artery Anomaly; Double Right Coronary Artery

    Directory of Open Access Journals (Sweden)

    Orhan Önalan

    2010-12-01

    Full Text Available A double right coronary artery is an extremely rare coronary artery anomaly. Difficulties in diagnosis might cause underestimation of the incidence of double right coronary artery. Interestingly, most of the cases about this anomaly were reported from Turkey. In this case report, we aimed to present double right coronary artery in a patient who was admitted with atypic chest pain.

  1. Total Arterial Myocardial Revascularization

    International Nuclear Information System (INIS)

    Total arterial myocardial revascularization is an attempt to overcome the problems of late vein graft atherosclerosis occlusion and need for coronary re-operations. Despite increasing evidence of efficacy, the use of arterial conduits has not been accepted. as primary practice in most of the centers in Pakistan for various reasons. We analyze our initial experience to assess the feasibility of total arterial revascularization as a primary strategy in patients requiring first time coronary artery bypass grafting. Two hundred patients undergoing first time CABG at our institution, from January 2000 to April 2001, were studied. Group one consisted of 100 patients undergoing total arterial revascularization (using bilateral internal thoracic and radial arteries) and group two consisted of 100 patients undergoing conventional CABG (using one internal thoracic artery and supplemental veins).Thirty day mortality and early morbidity with particular reference to resternotomy for bleeding, cerebrovascular accidents, renal failure, and sternal dehiscence were the main outcome measures. Patients in Group 1 were younger (56.2+-10.4 vs. 60.3+-9.8 years; P<0.001), had lower Parsonnet scores (4.8+-0.4 vs. 9.6+-1.8; P<0.001), and had better left ventricular function. Both groups received a similar number of grafts. The percentage of patients undergoing total arterial revascularization rose from 20% in the first three months to over 65% in three later three-months period. Overall 30-day mortality was 1.5%, one patient (1%) in Group1 and two patients (2%) in Group2. There was similar incidence of postoperative complications and length of median postoperative stay in both groups. Total arterial revascularization can be adopted as a primary strategy in most patients undergoing CABG with no increase in mortality or morbidity. (author)

  2. Mitochondrial Protection by Exogenous Otx2 in Mouse Retinal Neurons

    Directory of Open Access Journals (Sweden)

    Hyoung-Tai Kim

    2015-11-01

    Full Text Available OTX2 (orthodenticle homeobox 2 haplodeficiency causes diverse defects in mammalian visual systems ranging from retinal dysfunction to anophthalmia. We find that the retinal dystrophy of Otx2+/GFP heterozygous knockin mice is mainly due to the loss of bipolar cells and consequent deficits in retinal activity. Among bipolar cell types, OFF-cone bipolar subsets, which lack autonomous Otx2 gene expression but receive Otx2 proteins from photoreceptors, degenerate most rapidly in Otx2+/GFP mouse retinas, suggesting a neuroprotective effect of the imported Otx2 protein. In support of this hypothesis, retinal dystrophy in Otx2+/GFP mice is prevented by intraocular injection of Otx2 protein, which localizes to the mitochondria of bipolar cells and facilitates ATP synthesis as a part of mitochondrial ATP synthase complex. Taken together, our findings demonstrate a mitochondrial function for Otx2 and suggest a potential therapeutic application of OTX2 protein delivery in human retinal dystrophy.

  3. [Physiological functional evaluation of retinal implants in animal models].

    Science.gov (United States)

    Eckhorn, R; Stett, A; Schanze, T; Gekeler, F; Schwahn, H; Zrenner, E; Wilms, M; Eger, M; Hesse, L

    2001-04-01

    Retinal implants can--by electrical stimulation--create visual impressions in people with certain kinds of degenerative retinal diseases (e.g. Retinitis Pigmentosa). Electrically evoked potentials in the retina must be transferred into the visual cortex in an orderly manner, a prerequisite for any kind of form- and movement-perception. In the current developmental stage the difficult investigations are performed in various animal models: isolated retinae of intact chicken and of RCS-rats (a model for Retinitis Pigmentosa), as well as in anesthetised rabbits, pigs and cats with intact retinae. Our investigations show that spatially selective ganglion-cell responses can be recorded following focal electrical stimulation, in healthy and as well in degenerated retinae. Registration of activities in area 17 of the visual cortex demonstrate that electrical retinal stimulation can indeed activate it. PMID:11374278

  4. Rickettsia retinitis cases in India: a few comments.

    Science.gov (United States)

    Tripathy, Koushik; Chawla, Rohan; Sharma, Yog Raj; Vohra, Rajpal

    2016-12-01

    An important cause of infectious retinitis, not well-described in Indian literature, has been analyzed in detail systematically by Kawali A. and colleagues. However, Rickettsia retinitis (RR) was diagnosed at titres of 1:160 by the Weil-Felix test (WFT). The sensitivity and specificity of WFT at this level are poor compared to the gold standard immunofluorescent antibody assay. However, we understand that financial constraints of the Indian patients limit the availability of more definite tests. In our opinion, the optical coherence tomography features of RR described by the authors may be mimicked by other causes of retinitis, such as toxoplasma retinitis or even cotton wool spots. Infectious retinitis including RR should be treated by an antimicrobial agent with or without oral steroids until larger series or randomized controlled trials prove otherwise. PMID:26920002

  5. [Clinical risk factors of vitreoretinal proliferations in rhegmatogenous retinal detachment].

    Science.gov (United States)

    Bonnet, M

    1994-01-01

    PVR is a complication of rhegmatogenous retinal detachment which can occur only in predisposed eyes. Preoperative PVR and postoperative PVR can develop solely in retinal detachments associated with retinal breaks related to vitreous traction (horse-shoe tears, operculated tears, crescent tears and paravascular tears of the postequatorial region). PVR never develops in retinal detachments due to retinogenic retinal breaks (atrophic holes in lattice, and oral dialysis). There are 3 independent risk factors for postoperative PVR whose role has been demonstrated: preoperative PVR, horse-shoe tears extending on 90 degrees or more of the eye circumference, and horse-shoe tears with a curled and fixed posterior edge. The role of preoperative choroidal detachment as an independent risk factor, although likely, remains to be demonstrated. Cryotreatment is a risk factor for postoperative PVR solely in predisposed eyes. An alternative method to cryo should be used in high risk eyes. PMID:7989662

  6. Intrinsic optical signal imaging of retinal physiology: a review

    Science.gov (United States)

    Yao, Xincheng; Wang, Benquan

    2015-09-01

    Intrinsic optical signal (IOS) imaging promises to be a noninvasive method for high-resolution examination of retinal physiology, which can advance the study and diagnosis of eye diseases. While specialized optical instruments are desirable for functional IOS imaging of retinal physiology, in depth understanding of multiple IOS sources in the complex retinal neural network is essential for optimizing instrument designs. We provide a brief overview of IOS studies and relationships in rod outer segment suspensions, isolated retinas, and intact eyes. Recent developments of line-scan confocal and functional optical coherence tomography (OCT) instruments have allowed in vivo IOS mapping of photoreceptor physiology. Further improvements of the line-scan confocal and functional OCT systems may provide a feasible solution to pursue functional IOS mapping of human photoreceptors. Some interesting IOSs have already been detected in inner retinal layers, but better development of the IOS instruments and software algorithms is required to achieve optimal physiological assessment of inner retinal neurons.

  7. Retinal Blood Vessel Segmentation with Optic Disc Pixels Exclusion

    Directory of Open Access Journals (Sweden)

    Randy Cahya Wihandika

    2013-06-01

    Full Text Available The morphological changes of retinal blood vessels are important indicators used to diagnose and monitor the progression of various diseases. A number of retinal blood vessel segmentation methods have been introduced, including the line operator based methods, which have shown satisfactory results. However, the basic line operator method cannot discriminate the pixels around the retinal optic disc, resulting in false classification of those pixels. In this paper, we integrate the detection of pixels around the retinal optic disc to the line operator method so that those pixels can be excluded from the vessel pixels. The method is evaluated on the widely used retinal dataset, the DRIVE dataset. The results demonstrate that the proposed method has made improvements over the basic and the multi-scale line detector with accuracy and area under curve of 0.942 and 0.9521, respectively.

  8. Patterned retinal coagulation with a scanning laser

    Science.gov (United States)

    Palanker, Daniel; Jain, ATul; Paulus, Yannis; Andersen, Dan; Blumenkranz, Mark S.

    2007-02-01

    Pan-retinal photocoagulation in patients with diabetic retinopathy typically involves application of more than 1000 laser spots; often resulting in physician fatigue and patient discomfort. We present a semi-automated patterned scanning laser photocoagulator that rapidly applies predetermined patterns of lesions; thus, greatly improving the comfort, efficiency and precision of the treatment. Patterns selected from a graphical user interface are displayed on the retina with an aiming beam, and treatment can be initiated and interrupted by depressing a foot pedal. To deliver a significant number of burns during the eye's fixation time, each pulse should be considerably shorter than conventional 100ms pulse duration. We measured coagulation thresholds and studied clinical and histological outcomes of the application of laser pulses in the range of 1-200ms in pigmented rabbits. Laser power required for producing ophthalmoscopically visible lesions with a laser spot of 132?m decreased from 360 to 37mW with pulse durations increasing from 1 to 100ms. In the range of 10-100ms clinically and histologically equivalent light burns could be produced. The safe therapeutic range of coagulation (ratio of the laser power required to produce a rupture to that for a light burn) decreased with decreasing pulse duration: from 3.8 at 100ms, to 3.0 at 20ms, to 2.5 at 10ms, and to 1.1 at 1ms. Histology demonstrated increased confinement of the thermal damage with shorter pulses, with coagulation zone limited to the photoreceptor layer at pulses shorter than 10ms. Durations of 10-20ms appear to be a good compromise between the speed and safety of retinal coagulation. Rapid application of multiple lesions greatly improves the speed, precision, and reduces pain in retinal photocoagulation.

  9. Renal artery stenosis

    International Nuclear Information System (INIS)

    Renal artery disease is a potentially correctable cause of hypertension. Previous studies have suggested the utility of duplex sonography in accurately detecting and grading the severity of renal artery stenosis. The purpose of this paper is to evaluate color flow Doppler for this use. Forty-three kidneys were examined by color-flow Doppler and conventional duplex sampling in patients with suspected renovascular hypertension or those undergoing aortography for unrelated reasons. Doppler tracings were obtained from the renal arteries and aorta with calculation of the renal aortic ratio (RAR) and resistive index (RI). Results of Doppler sampling with color flow guidance were compared with aortograms in a blinded fashion

  10. Permanent retinal injury from recreational laser pointer.

    Science.gov (United States)

    Noble, Carl; Blice, Jeffrey

    2015-03-01

    This case report was performed to display the visually significant damage to the retina that can occur with brief exposure to a handheld laser pointer. Laser use in the military is ever increasing in form of target designators, rangefinders, or radar warning systems with powers far greater than used in this case. There is great potential for future cases of retinal damage among active duty members, and the importance of prevention through laser safety programs and recognition through trained medical personnel is paramount. PMID:25735035

  11. Isolated right pulmonary artery discontinuity

    OpenAIRE

    Turner, DR; Vincent, JA; Epstein, ML

    2000-01-01

    Unilateral “absence” of the pulmonary artery is an uncommon malformation frequently associated with congenital heart disease. In fact, the pulmonary artery is typically discontinuous from the main pulmonary artery, not absent. We report a case of right pulmonary artery discontinuity not associated with congenital heart disease and review the embryogenesis and treatment of this rare congenital cardiac anomaly.

  12. Visual recovery in a patient with total hyphema, neovascular glaucoma, long-standing retinal detachment and no light perception vision: a case report

    Directory of Open Access Journals (Sweden)

    Liebmann Jeffrey M

    2011-06-01

    Full Text Available Abstract Introduction We report the case of a patient with total hyphema, neovascular glaucoma, long-standing retinal detachment and no light perception vision, who regained counting fingers vision with complete regression of neovascularization following anterior chamber washout, intravitreal bevacizumab, pars plana vitrectomy, and silicone oil placement. This represents a rare case in which a patient with no light perception vision was able to regain functional vision. Case presentation A 63-year-old Caucasian man with a 55-year history of long-standing retinal detachment after trauma presented to our facility with pain and redness, a total hyphema, no light perception vision and an intraocular pressure of 60 mmHg (right eye. He had a history of diabetes mellitus and coronary artery disease. Following anterior chamber washout, he was found to have neovascular glaucoma, for which intravitreal bevacizumab was administered. After washout and intraocular pressure control, his visual acuity improved to light perception. He subsequently underwent vitrectomy, membrane peeling, endolaser and silicone oil placement to reattach his retina, and then a second retinal reattachment procedure. Following these procedures, he had visual recovery to counting fingers vision in his right eye at five metres, complete regression of neovascularization, and intraocular pressure of 10 to 12 mmHg on one antiglaucoma medication. Conclusion Functional vision can be regained despite long-standing retinal detachment.

  13. Retinal vessel calibers predict long-term microvascular complications in type 1 diabetes : the Danish Cohort of Pediatric Diabetes 1987 (DCPD1987)

    DEFF Research Database (Denmark)

    Broe, Rebecca; Rasmussen, Malin L

    2014-01-01

    Diabetic neuropathy, nephropathy, and retinopathy cause significant morbidity in patients with type 1 diabetes, even though improvements in treatment modalities delay the appearance and reduce the severity of these complications. To prevent or further delay the onset, it is necessary to better understand common underlying pathogenesis and to discover preclinical biomarkers of these complications. Retinal vessel calibers have been associated with the presence of microvascular complications, but their long-term predictive value has only been sparsely investigated. We examined retinal vessel calibers as 16-year predictors of diabetic nephropathy, neuropathy, and proliferative retinopathy in a young population-based Danish cohort with type 1 diabetes. We used semiautomated computer software to analyze vessel diameters on baseline retinal photos. Calibers of all vessels coursing through a zone 0.5-1 disc diameter from the disc margin were measured and summarized as the central artery and vein equivalents. In multiple regression analyses, we found wider venular diameters and smaller arteriolar diameters were both predictive of the 16-year development of nephropathy, neuropathy, and proliferative retinopathy. Early retinal vessel caliber changes are seemingly early markers of microvascular processes, precede the development of microvascular complications, and are a potential noninvasive predictive test on future risk of diabetic retinopathy, neuropathy, and nephropathy.

  14. Retinal Vessel Calibers Predict Long-term Microvascular Complications in Type 1 Diabetes Mellitus : The Danish Cohort of Pediatric Diabetes 1987 (DCPD1987)

    DEFF Research Database (Denmark)

    Broe, Rebecca; Rasmussen, Malin L

    2014-01-01

    Diabetic neuropathy, nephropathy and retinopathy cause significant morbidity in patients with type 1 diabetes, even though improvements in treatment modalities delay the appearance and reduce the severity of these complications. To prevent or further delay the onset, it is necessary to better understand common underlying pathogenesis and to discover pre-clinical biomarkers of these complications.Retinal vessel calibers have been associated with the presence of microvascular complications but their long-term predictive value has only been sparsely investigated.We examined retinal vessel calibers as 16-year predictors of diabetic nephropathy, neuropathy and proliferative retinopathy in a young population-based Danish cohort with type 1 diabetes. We used semi-automated computer software to analyze vessel diameters on baseline retinal photos. Calibers of all vessels coursing through a zone 0.5-1 disc diameter from the disc margin were measured and summarized as the central artery and vein equivalents.In multiple regression analyzes we found both wider venular diameters and smaller arteriolar diameters to be predictive of the 16-year development of nephropathy, neuropathy and proliferative retinopathy. Early retinal vessel caliber changes are seemingly early markers of microvascular processes, precede the development of microvascular complications and a potential non-invasive predictive test on future risk of diabetic retinopathy, neuropathy and nephropathy.

  15. The age-dependent decrease in the myogenic response of retinal arterioles as studied with the Retinal Vessel Analyzer

    DEFF Research Database (Denmark)

    Jeppesen, Peter; Gregersen, Pernille Axel; Bek, Toke

    2004-01-01

    PURPOSE: To study the age-dependent change in myogenic response of retinal arterioles. METHODS: Fifty-one healthy volunteers with at least ten persons in each of the five age decades (I-V) between 20 and 69 years were subjected to diameter measurement of retinal arterioles using the Retinal Vessel...... Analyzer (RVA) during rest and during an increase in the systemic blood pressure when lifting hand weights. The transmural pressure in the retinal arterioles during the procedures was estimated from the blood pressure and the intraocular pressure and was compared to the accompanying diameter response....... RESULTS: The retinal arteriolar diameter showed a significant decrease as a function of increasing weight for the two younger age groups below the age of 40 years (P=0.007, group I, and P=0.049, group II), compatible with perfect autoregulation, whereas no such change was observed in persons above this...

  16. Atherosclerotic femoral artery aneurysms

    DEFF Research Database (Denmark)

    Levi-Mazloum, Niels Donald; Schroeder, T V

    1996-01-01

    Based on a clinical suspicion of an increase in the proportion of deep femoral aneurysms, we reviewed the case records of patients who underwent reconstructive procedures for femoral aneurysms to investigate if this could be confirmed and explained by selection of patient or modality of diagnosis....... A study was made of 17 atherosclerotic femoral aneurysms operations occurring in 17 patients from 1989 to 1994. Eleven associated aneurysms were found. Eleven patients presented with an expanding swelling, 4 with rupture 3 with thrombosis and 2 were asymptomatic. Fourteen aneurysms involved the...... common femoral artery and 3 the deep femoral artery. The proportion of deep femoral aneurysm was therefore 3/17 = 18%. Previous series report that aneurysms of the profunda femoris artery occurs in only 1% to 2.6% of all femoral artery aneurysms. No explanation was found for this significant increase (p...

  17. Pulmonary Arterial Hypertension

    Science.gov (United States)

    Pulmonary Arterial Hypertension What Is Pulmonary Hypertension? To understand pulmonary hypertension (PH) it helps to understand how blood ows throughout your body. While the heart is one organ, it ...

  18. Renal arteries (image)

    Science.gov (United States)

    A renal angiogram is a test used to examine the blood vessels of the kidneys. The test is performed ... main vessel of the pelvis, up to the renal artery that leads into the kidney. Contrast medium ...

  19. Cerebral Arterial Fenestrations

    OpenAIRE

    Cooke, Daniel L; Stout, Charles E; Kim, Warren T.; Kansagra, Akash P.; Yu, John Paul; Gu, Amy; Jewell, Nicholas P.; Steven W. Hetts; Randall T. Higashida; Dowd, Christopher F; Van V. Halbach

    2014-01-01

    Arterial fenestrations are an anatomic variant with indeterminate significance. Given the controversy surrounding fenestrations we sought their prevalence within our practice along with their association with other cerebrovascular anomalies.

  20. Uterine artery embolization - discharge

    Science.gov (United States)

    Uterine fibroid embolization - discharge; UFE - discharge; UAE - discharge ... You had uterine artery embolization (UAE). UAE is a procedure to treat fibroids using radiology instead of surgery. During the procedure, the blood supply of the fibroids ...