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Sample records for tortuous retinal arteries

  1. 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.)

  2. Vertebral artery origin stenting with buddy wire technique in tortuous subclavian artery

    Energy Technology Data Exchange (ETDEWEB)

    Kizilkilic, Osman [Baskent University Department of Radiology, Adana Teaching and Medical Research Center, 01170 Yuregir-Adana (Turkey)]. E-mail: ebos90@hotmail.com

    2007-01-15

    Catheterization of vessels with severe tortuosity and atherosclerotic changes may represent a technical challenge and is associated with a higher incidence of vascular complications [Putman CM, Chaloupka JC. Use of large-caliber coronary guiding catheters for neurointerventional applications. AJNR Am J Neuroradiol 1996;17:697-704]. Placement of guiding catheter to the tortuous subclavian artery in vertebral artery origin stenting procedure is such a condition with difficulties. In the presence of severe tortuosity of aortic arch and proximal subclavian artery placement of guiding catheter may be difficult and yield poor backup support. We describe a technique that uses a buddy wire to make the guiding catheter stable in its proper position and make possible to perform stenting the vertebral artery origin stenosis.

  3. Vertebral artery origin stenting with buddy wire technique in tortuous subclavian artery

    International Nuclear Information System (INIS)

    Catheterization of vessels with severe tortuosity and atherosclerotic changes may represent a technical challenge and is associated with a higher incidence of vascular complications [Putman CM, Chaloupka JC. Use of large-caliber coronary guiding catheters for neurointerventional applications. AJNR Am J Neuroradiol 1996;17:697-704]. Placement of guiding catheter to the tortuous subclavian artery in vertebral artery origin stenting procedure is such a condition with difficulties. In the presence of severe tortuosity of aortic arch and proximal subclavian artery placement of guiding catheter may be difficult and yield poor backup support. We describe a technique that uses a buddy wire to make the guiding catheter stable in its proper position and make possible to perform stenting the vertebral artery origin stenosis

  4. Sequential occlusion of the branch retinal artery and branch retinal vein in a patient with hypertension: an interventional case report

    Directory of Open Access Journals (Sweden)

    Okamoto N

    2014-10-01

    Full Text Available Norio Okamoto, Chota Matsumoto, Yoshikazu Shimomura Department of Ophthalmology, Kinki University Faculty of Medicine, Osakasayama City, Osaka, Japan Background: There are some cases that reported central retinal vein occlusion accompanied by ciliary artery occlusion, however, combined branch retinal artery and vein occlusion is a rare condition that has been infrequently reported. We describe in this report one case of retinal vein occlusion and branch retinal artery occlusion occurring simultaneously.Case presentation: A 50 year-old woman presented with acute visual loss in her right eye. Fundus photography showed retinal ischemia and tortuous, dilated retinal veins in the right eye. With early phase fluorescein angiography, retinal arteries revealed areas absent of branches. Late phase fluorescein angiography demonstrated that areas absent of branches were still present.Conclusion: It is a rare case of branch retinal artery and vein occlusion. Keywords: branch retinal artery occlusion, branch retinal vein occlusion, retinal vessel

  5. Pulsatile Tinnitus due to a Tortuous Siphon-Like Internal Carotid Artery Successfully Treated by Arterial Remodeling

    OpenAIRE

    Dirk de Ridder; Sven Vanneste; Tomas Menovsky

    2013-01-01

    A patient is described with a right-sided tortuous siphon-like extracranial internal carotid artery leading to highly distressing ipsilateral heart beat synchronous pulsatile tinnitus, scoring 9/10 measuring loudness. Dilating the balloon during the occlusion test in or distal to the siphon-like anomaly reduces the arterial pulsations. Subsequently, surgery is performed using Teflon as an external construct to straighten the siphon-like anomaly. Postoperatively, the pulsations improve to 5/10...

  6. Stenting of Vertebral Artery Origin with the Buddy Wire Technique in Tortuous Subclavian Artery: A Case Report

    OpenAIRE

    Uysal, E.; Caliskan, C.; Caymaz, I?; Orken, D. N.; Basak, M.

    2010-01-01

    Tortuous vasculature is a common reason for failure to stabilize a guiding catheter in an appropiate position and is associated with a higher incidence of vascular complications. In such a case, the guiding catheter often buckles into the aorta during an attempt to place the balloon or stent. In this report, we used the buddy wire technique to support the guiding catheter, and we passed through the vertebral artery origin stenosis with the help of a microcatheter-microguidewire combination wh...

  7. Stenting of vertebral artery origin with the buddy wire technique in tortuous subclavian artery. A case report.

    Science.gov (United States)

    Uysal, E; Caliskan, C; Caymaz, I; Orken, D N; Basak, M

    2010-06-01

    Tortuous vasculature is a common reason for failure to stabilize a guiding catheter in an appropriate position and is associated with a higher incidence of vascular complications. In such a case, the guiding catheter often buckles into the aorta during an attempt to place the balloon or stent. In this report, we used the buddy wire technique to support the guiding catheter, and we passed through the vertebral artery origin stenosis with the help of a microcatheter-microguidewire combination which enabled stent deployment. We kept the buddy wire through the guiding catheter throughout the procedure and the 6F guiding catheter allowed passages of both buddy wire and stent system. PMID:20642892

  8. Pulsatile Tinnitus due to a Tortuous Siphon-Like Internal Carotid Artery Successfully Treated by Arterial Remodeling

    Science.gov (United States)

    De Ridder, Dirk; Menovsky, Tomas

    2013-01-01

    A patient is described with a right-sided tortuous siphon-like extracranial internal carotid artery leading to highly distressing ipsilateral heart beat synchronous pulsatile tinnitus, scoring 9/10 measuring loudness. Dilating the balloon during the occlusion test in or distal to the siphon-like anomaly reduces the arterial pulsations. Subsequently, surgery is performed using Teflon as an external construct to straighten the siphon-like anomaly. Postoperatively, the pulsations improve to 5/10 in a standing position and disappear during a reclined position. By adding a hearing aid, the pulsations are almost completely gone during a standing position (1/10) and remain absent in a reclined position. PMID:23607023

  9. Idiopathic pediatric retinal artery occlusion

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    Manayath George

    2010-01-01

    Full Text Available We report a case of branch retinal artery occlusion (BRAO in a healthy young girl. An eight-year-old girl presented with sudden loss of vision in her left eye. She had a pale retina with macular edema consistent with extensive BRAO. A thorough workup was performed to determine any etiologic factor. All test results were within normal limits. Her visual acuity improved from finger counting to 20/40 over two weeks, on immediate treatment with intravenous steroids (methyl prednisolone. This case suggests that BRAO can occur in healthy children without any detectable systemic or ocular disorders and a dramatic improvement may be achieved with prompt treatment with intravenous steroids.

  10. Impending central retinal vein occlusion associated with cilioretinal artery obstruction

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    Juliana Mantovani Bottós

    2008-10-01

    Full Text Available Juliana Mantovani Bottós, Fabio Bom Aggio, Eduardo Dib, Michel Eid FarahVision Institute, Department of Ophthalmology, Federal University of São Paulo, BrazilAbstract: We report a case of a patient with an impending central retinal vein occlusion (CRVO with cilioretinal artery obstruction, which may help to understand the nature of the retinal hemodynamic changes associated with CRVO which shows direct evidence of arterial vasospasm, suggesting an increased contractility of retinal arteries. The clinical course, with initial retinal whitening along a cilioretinal artery followed by signs of venous stasis, seems to confirm the pathogenesis hypothesis concerning a primary arterial affection due to arterial vasospasm.Keywords: retinal vein occlusion, cilioretinal artery obstruction, arterial spasm, fluorescein angiography

  11. 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...

  12. Concurrent central retinal artery occlusion and branch retinal vein occlusion in giant cell arteritis

    OpenAIRE

    Edward R Chu; Celia S Chen

    2010-01-01

    Edward R Chu, Celia S ChenDepartment of Ophthalmology, Flinders Medical Centre and Flinders University, Bedford Park, SA, AustraliaAbstract: Ophthalmic involvement in giant cell arteritis can manifest in a number of ways. Central retinal artery occlusion is one of the common causes of visual loss in giant cell arteritis. On the contrary, branch retinal vein occlusion is rarely associated with the latter. We report an 89-year-old lady with acute left central retinal artery occlusion on a backg...

  13. Retinal Arterial Macroaneurysm. A Case Report Macroaneurisma arterial retinal. Presentación de un caso.

    Directory of Open Access Journals (Sweden)

    Aimé Broche Hernández

    2011-08-01

    Full Text Available Retinal macroaneurysms are saccular dilatations of the retinal arteries. They commonly appear in temporary arches, which are found in elderly patients with hypertension and / or generalized vascular disease. They are slightly more frequent in women. In this article we present a case with a macroaneurysm rupture that was treated with laser photocoagulation and evolved favorably.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.

  14. 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

  15. A ruptured retinal arterial macroaneurysm presenting as subhyaloid haemorrhage

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    Vaidya Ashish

    2002-01-01

    Full Text Available We report a case of ruptured retinal arterial macroaneurysm with overlying subhyaloid haemorrhage. Both subhyaloid haemorrhage and subsequently the macroaneurysm was treated with argon laser photocoagulation

  16. Impending central retinal vein occlusion associated with cilioretinal artery obstruction

    OpenAIRE

    Juliana Mantovani Bottós; Fabio Bom Aggio; Eduardo Dib; Michel Eid Farah

    2008-01-01

    Juliana Mantovani Bottós, Fabio Bom Aggio, Eduardo Dib, Michel Eid FarahVision Institute, Department of Ophthalmology, Federal University of São Paulo, BrazilAbstract: We report a case of a patient with an impending central retinal vein occlusion (CRVO) with cilioretinal artery obstruction, which may help to understand the nature of the retinal hemodynamic changes associated with CRVO which shows direct evidence of arterial vasospasm, suggesting an increased contractilit...

  17. 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

  18. A case of cilioretinal artery occlusion resembling hemicentral retinal artery occlusion

    OpenAIRE

    Sato Y.; Ohkawara Y; Makino S

    2012-01-01

    Shinji Makino, Yuriko Ohkawara, Yukihiro SatoDepartment of Ophthalmology, Jichi Medical University, Shimotsuke, Tochigi, JapanAbstract: A 77-year-old man presented with an inferior hemivisual field defect in the left eye. Funduscopy revealed well demarcated retinal edema of the superior quadrant resembling hemicentral retinal artery occlusion. Further, the upper and inferior retinal arteries emerged separately from the optic disc. Fluorescein angiography demonstrated a marked filling delay of...

  19. Retinal arterial occlusion in Takayasu?s arteritis

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    Kaushik Sushmita

    2005-01-01

    Full Text Available Takayasu?s arteritis is an auto-immune disorder of the large and medium-sized arteries, commonly involving the heart and its main vessels. It is now recognised that the inflammatory process of the large arteries affects regions of the walls supplied by the vasa vasorum, suggesting that primary small vessel involvement may contribute to the development of the clinico-pathological features of Takayasu aorto-arteritis. Classical ophthalmic features of the disease result from reduced ocular perfusion, which manifests as hypoxic retinal changes such as microaneurysms, arterio-venous anastomosis and non-perfused areas. Branch retinal artery occlusion has not been previously described in this condition. This case illustrates retinal arterial occlusion as the presenting feature of Takayasu?s arteritis.

  20. Retinal arterial macroaneurysms: a retrospective study of 40 patients.

    OpenAIRE

    Lavin, M. J.; Marsh, R. J.; Peart, S.; Rehman, A.

    1987-01-01

    We studied 40 patients with a total of 44 retinal arterial macroaneurysms. All patients were followed up for at least six months. Macroaneurysms (MAs) have variable clinical presentations and are still frequently misdiagnosed before fluorescein angiography. Haemorrhagic MAs were most frequently misdiagnosed (75%), and had a sudden onset with a relatively poor visual outcome. Patients with these MAs had higher systolic blood pressures and significantly fewer associated retinal vein occlusions ...

  1. Retinal arterial macroaneurysms: risk factors and natural history.

    OpenAIRE

    Panton, R. W.; Goldberg, M. F.; Farber, M. D.

    1990-01-01

    A case control study was conducted to identify the systemic and ocular risk factors for retinal arterial macroaneurysms. Forty-three patients with 52 photographically confirmed macroaneurysms were located. Forty-three age-matched, race-matched concurrent control patients were also identified. The patients with macroaneurysms had decreased visual acuity (p less than 0.0001) and a higher prevalence of hypertension (p = 0.037), female sex (p = 0.099), and retinal vein occlusions (p = 0.055) than...

  2. Combined occlusion of the central retinal artery and central retinal vein following blunt ocular trauma: a case report.

    OpenAIRE

    Noble, M. J.; Alvarez, E. V.

    1987-01-01

    A healthy young woman suffered complete loss of the vision of one eye following a blunt ocular injury. She sustained a combined occlusion of the central retinal artery and central retinal vein of the affected eye. Initially few retinal haemorrhages were present, but they increased considerably in number and size during the day following injury.

  3. Central retinal artery occlusion: an unusual complication of snakebite

    Scientific Electronic Library Online (English)

    A., Bhalla; A. P., Jain; S., Banait; U. N., Jajoo; S.P., Kalantri.

    Full Text Available Snakebites are endemic in some parts of India, being associated with a number of complications. Ocular disturbances are rare, except for injury to the cornea or conjunctiva when the eye is directly exposed to the venom. In this work, we present a case of central retinal artery occlusion caused by sn [...] akebite.

  4. Central retinal artery occlusion: an unusual complication of snakebite

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    A. Bhalla

    2004-01-01

    Full Text Available Snakebites are endemic in some parts of India, being associated with a number of complications. Ocular disturbances are rare, except for injury to the cornea or conjunctiva when the eye is directly exposed to the venom. In this work, we present a case of central retinal artery occlusion caused by snakebite.

  5. 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

  6. Branch retinal artery occlusion secondary to dengue fever

    OpenAIRE

    Kanungo Sanghamitra; Shukla Dhananjay; Kim Ramasamy

    2008-01-01

    Dengue is known to affect the posterior segment of the eye, with a range of hemorrhagic and inflammatory sequelae. A 28-year-old lady convalescing from dengue fever complained of unilateral blurring of inferior visual field. She was evaluated clinically and with fluorescein angiography. Her best-corrected visual acuity was 20/20 bilaterally. Fundus examination revealed a branch retinal artery occlusion in the right eye. Fluorescein angiogram confirmed the clinical diagnosis; and also revealed...

  7. Sequential occlusion of the branch retinal artery and branch retinal vein in a patient with hypertension: an interventional case report

    OpenAIRE

    Okamoto N; Matsumoto C; Shimomura Y

    2014-01-01

    Norio Okamoto, Chota Matsumoto, Yoshikazu Shimomura Department of Ophthalmology, Kinki University Faculty of Medicine, Osakasayama City, Osaka, Japan Background: There are some cases that reported central retinal vein occlusion accompanied by ciliary artery occlusion, however, combined branch retinal artery and vein occlusion is a rare condition that has been infrequently reported. We describe in this report one case of retinal vein occlusion and branch retinal artery occlusion occurring simu...

  8. Superselective ophthalmic intraarterial thrombolysis for central retinal artery thrombosis

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of superselective ophthalmic artery thrombolysis for treatment of central retinal artery (CRAT). Methods: 250000-500000 u urokinase was directly perfused via ophthalmic artery (OA) through the retained superselective catheter after angiography into 8 eyes of 8 patients with CRAT. Results: The visual acuity (VA) was significantly improved in 4 eyes. the VA of 3 eyes reached 0.1-0.3 after 6 months follow-up. the other 3 eyes achieved no significant improvement of VA. The VA of 1 eye decreased from finger count (FC) to light perception (LP). Conclusions: Early diagnosis and early superselective trans-micro catheter thrombolysis would be more effective than traditional treatment. (authors)

  9. Oclusão de ramo arterial retiniano bilateral / Bilateral branch retinal artery occlusion

    Scientific Electronic Library Online (English)

    Luiz Guilherme Azevedo de, Freitas; David Leonardo Cruvinel, Isaac; Luiz Alexandre Rassi, Gabriel; Lívia Carla de Souza Nassar, Bianchi; Marcos Pereira de, Ávila.

    2013-08-01

    Full Text Available Os autores relatam o caso de uma paciente que apresentou quadro bilateral de oclusão de ramos arteriais da retina sem causas sistêmicas identificáveis para o aparecimento da doença. [...] Abstract in english The authors report a case of a patient who presented bilateral branch retinal artery occlusion without any meaningful systemic underlying conditions. [...

  10. 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

  11. Traumatic Optic Neuropathy and Central Retinal Artery Occlusion Following Blunt Ocular Trauma

    OpenAIRE

    Cumurcu, Tongabay; Doganay, Selim; Demirel, Soner; Cankaya, Cem

    2011-01-01

    We present a case as a rare sign of traumatic optic neuropathy and central retinal artery occlusion following blunt ocular trauma. A 10-year-old child suffered complete loss of the vision of one eye following a blunt ocular injury. He sustained an occlusion of the central retinal artery and traumatic optic neurupathy of the affected eye. Isolated cases of central retinal vessel occlusions and traumatic optic neurapathy following ocular blunt trauma are rare conditions. Clinicians to be aware ...

  12. Carotid arteries in central retinal vessel occlusion as assessed by Doppler ultrasound.

    OpenAIRE

    Peternel, P; Keber, D.; Videcnik, V

    1989-01-01

    Doppler ultrasound was used to detect possible flow changes in the carotid arteries of patients with central retinal artery and vein occlusion. Twenty-three patients with central retinal artery occlusion (mean age 56, SD 11, years) were examined 4 to 48 months after the development of the occlusion and compared with age and sex matched control subjects with no history of any disease known to be associated with pathological changes in carotid vessels. Significant stenosis or occlusion of one o...

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

    DEFF Research Database (Denmark)

    Gesslein, Bodil; Gustafsson, Lotta

    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, and this study was therefore designed to examine the retinal vasculature separately from the neuroretina.

  14. Effectiveness of combined laser photocoagulation therapy with intravitreal anti -VEGF in Retinal arterial macroaneurysms: case report

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    Fernanda Pacella

    2014-12-01

    Full Text Available Background: Retinal arterial macroaneurysms (RAM is a pathological dilatation of retinal arterial vessel. Argon laser photocoagulation has been for a long time the gold standard of many vascular diseases of the retina such as macroaneurysm. From this work emerges how the introduction of intravitreal anti-VEGF therapies have enhanced the 'effectiveness of the combination of argon laser photocoagulation in cases of persistent retinal edema, we present the case of a retinal macroaneurysm with macular hemorrhage focus and oedema in a patient with a history of systemic arterial hypertension. Methods: A 77 year-old woman patient reported sudden decline in visual acuity in the left eye; the best corrected visual acuity (BCVAwas 1/10 in left eye. Fluorescein angiography (FAG resulted in diagnosis of Macroaneurysm at the posterior pole with macular hemorrhage focus and oedema. The patient was treated with laser treatment in the left eye; after 30 days, the visual acuity was 1/50 and at optical coherence tomography (OCT the retinal profile was significantly altered. After 30 days, a single intravitreal ranibizumab injection was performed and, after 7 days, visual acuity was 1/10. After 24 months from ranibizumab-based therapy the final visual acuity was 10/10 and OCT examination revealed a normal retinal profile. Conclusion: In this case report the association of argon laser photocoagulation with intravitreal anti-VEGF injection has been proven to be effective and safe in case of persistent retinal oedema.

  15. Correlation between penile cavernosal artery blood flow and retinal vascular findings in arteriogenic erectile dysfunction

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    Ahmed M Emarah

    2010-09-01

    Full Text Available Ahmed M Emarah1, Shawky M El-Haggar2, Ihab A Osman2, Abdel Wahab S Khafagy21Departments of Ophthalmology, 2Andrology and Sexology, Cairo University Hospital, EgyptObjectives: Arteriogenic erectile dysfunction (ED is a target organ disease of atherosclerosis, and therefore might be a predictor of systemic atherosclerosis. Being systemic, it might be possible to evaluate the extent of atherosclerosis from retinal vascular findings. We investigated the possible correlation between penile cavernosal artery blood flow and retinal vascular findings in patients with arteriogenic ED.Patients and methods: Sixty patients with ED were divided according to the peak systolic velocity (PSV in their penile cavernosal arteries into two groups; Group A included 30 patients with PSV less than 25 cm/sec, and Group B included 30 patients with PSV more than 35 cm/sec. Blood flow in the penile cavernosal artery was measured with color Doppler ultrasonography. All patients were assessed by ocular fundus examination under amydriatic conditions to evaluate retinal vascular atherosclerotic changes using Hyman’s classification.Results: Evidence of retinal vascular atherosclerotic changes was found in 19 patients (63.3% in Group A and in 10 patients (33.3% in Group B.Conclusions: Our study confirms the possibility of predicting penile arterial vascular status in patients with ED from their retinal vascular findings by using amydriatic simple, practical funduscopy.Keywords: erectile dysfunction, atherosclerosis, retinal vascular atherosclerosis

  16. Transluminal Nd:YAG laser embolysis: A reasonable method to reperfuse occluded branch retinal arteries

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    Stanca Horia T.

    2014-01-01

    Full Text Available Introduction. Central retinal artery occlusion (CRAO and branch retinal artery occlusion (BRAO result in partial or complete retinal ischemia and sudden loss of vision; at this moment, there is no effective therapy for CRAO and BRAO. Transluminal Nd:YAG laser embolysis (TYE represents a therapeutic approach used for retinal vascular occlusive diseases. The main indication is branch retinal artery occlusion with visible embolus; for central retinal artery occlusion this tehnique is hardly applicable. The principle of this method consists of intravascular embolus breakage using the 1064 nm Nd:YAG laser, focused on the embolus surface. Case report. We presented 5 cases with BRAO, 3 with infero-temporal and 2 with supero-temporal BRAO, all of them treated with TYE, with variable results. All the patients had a visible embolus within the BRA, the laser applications being delivered directly to the embolus. Conclusion. Despite our short-term experience regarding this therapeutical approach, we can resume that the moment of emboli distruction, as close as possible to the onset of the occlusion, is decisive for regaining vision and that applying the procedure correctly is superior to observation in most cases. Worldwide experience with TYE is still limited, but the technique seems feasible also when treating CRAO caused by visible emboli on the optic disc surface. This most certainly calls for random trials for identifying precisely the role of TYE in treatment of retinal occlusion pathology, though the relatively small number of properly diagnosed cases affects this objective. In all cases, the risks of TYE must be weighed against the possibility of severe and permanent loss of vision secondary to retinal artery occlusions.

  17. 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.

  18. Changes in central retinal artery blood flow after ocular warming and cooling in healthy subjects

    OpenAIRE

    Shamshad M; Amitava A; Ahmad I.; Wahab S

    2010-01-01

    Context: Retinal perfusion variability impacts ocular disease and physiology. Aim: To evaluate the response of central retinal artery (CRA) blood flow to temperature alterations in 20 healthy volunteers. Setting and Design: Non-interventional experimental human study. Materials and Methods: Baseline data recorded: Ocular surface temperature (OST) in °C (thermo-anemometer), CRA peak systolic velocity (PSV) and end diastolic velocity (EDV) in cm/s using Color Doppler. Ocular later...

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

    OpenAIRE

    Do-Hyun Kim; Jang Hwan Choi; Jung Ha Lee; Hee Sup Kim

    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 art...

  20. Vision Loss After Central Retinal Artery Occlusion Secondary to Orbital Sarcoid Mass.

    Science.gov (United States)

    Kim, Denise S; Korgavkar, Kaveri; Zahid, Sarwar; De Lott, Lindsey; Prabhakar, Avinash; Foerster, Bradley R; Besirli, Cagri G

    2014-07-28

    The authors describe the first report in the literature of central retinal artery occlusion as the presenting manifestation of sarcoidosis. A 33-year-old man with asthma, headache, and 6 days of intermittent, transient vision loss in the OS presented with persistent vision loss in the OS. Ophthalmic examination was consistent with diagnosis of central retinal artery occlusion in the OS. Vascular imaging with CT angiography revealed an incidental finding of an intraconal mass surrounding the left optic nerve and hilar lymphadenopathy. Bronchoscopic lymph node biopsy demonstrated noncaseating granulomas consistent with sarcoidosis. This case proffers a unique mechanism of vision loss in sarcoidosis and highlights that atypical causes of central retinal artery occlusion must be considered in patients without typical risk factors. PMID:25072221

  1. The tortuous behavior of lightning

    CERN Document Server

    Vera, F

    2002-01-01

    The complex branched structure of lightning induce scientists to think that dielectric breakdown is a very complicated phenomena, we will show that this is not true and that simulating the structure of lightning is an easy task, but depends strongly on boundary conditions. In this work we will introduce a new way of understanding the origin of this tortuous path that relies on minimizing the total energy stored in the system.

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

    OpenAIRE

    Ramezani Alireza; Haghighatkhah Hamidreza; Moghadasi Habibollah; Taheri Morteza; Parsafar Hiva

    2010-01-01

    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 e...

  3. The Feasibility of Central Retinal Artery Doppler Ultrasonography in Patients with Sudden Visual Disturbance that's Caused by Retinal Vascular Occlusion

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ji Won; Lee, Hui Joong; Lee, Jong Min [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2009-03-15

    We evaluated the usefulness of central retinal artery Doppler ultrasonography for assessing the patients with sudden visual disturbance that's caused by retinal vascular occlusion. The blood flow velocity and the resistive and pulsatile indexes were measured at the central retinal arteries of 65 patients with sudden visual disturbance. For all the subjects, the patient's affected eye was compared with the non-affected eye. We investigated the efficacy of the Doppler ultrasonography parameters to predict a significant visual loss on the Snellen test (<20/400). A significantly lower central retinal arterial flow velocity was measured in the affected eye as compared with the unaffected normal eye for all the subjects (p < 0.05). The ROC curves showed that the mean velocity was the best parameter to predict significant visual loss (p < 0.05). If a mean velocity of 4.3 cm/sec was chosen as the cutoff value to predict significant visual loss, then the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 89%, 95%, 95%, 88% and 92%, respectively (estimated area = 0.958, p-value <0.01). Central retinal artery Doppler ultrasonography was helpful for predicting significant visual loss in patients who complain of sudden visual disturbance. In addition to the other ophthalmologic diagnostic modalities, Doppler ultrasonography may be a feasible modality to depict impending further visual loss of an ischemic origin.

  4. Central retinal artery resistive index and optical coherence tomography in assessment of glaucoma progression

    Science.gov (United States)

    Ghany, Ahmed F. Abdel; Botros, Samer M.; El-Raggal, Tamer M.

    2015-01-01

    AIM To assess the relation between central retinal artery (CRA) resistive index (RI) and retinal nerve fiber thickness measured by optical coherence tomography (OCT) in assessment of disease progress in cases of open angle glaucoma. METHODS Twenty-three patients with diagnosed open angle glaucoma were included in this study. They were examined by colored duplex ultrasonography of CRA with estimation of RI of CRA and ophthalmic artery (OA) with estimation of CRA/OA RI ratio as well as OCT measurement of the average retinal nerve fiber layer (RNFL) thickness in order to assess the disease progress. RESULTS There was strong inverse relation between the increased RI in CRA as well as the increased CRA/OA RI ratio and the decrease in average RNFL thickness in cases of open angle glaucoma. CONCLUSION Assessment of CRA RI can indirectly assess the vascular changes associated with glaucoma and can assess the degree of retinal atrophy helping in evaluating prognosis thus guiding the choice of treatment. PMID:25938045

  5. 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.

  6. 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.

  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. Spontaneous central retinal artery occlusion in a teenager with sickle cell trait.

    Science.gov (United States)

    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 laboratory and radiological investigations. The blood investigations revealed SCT and abnormal partial thromboplastin time. The fundus fluorescein angiography revealed abnormal retinal vascular perfusion. Marked blood rheological impairment and activation of the coagulation pathway can occur without any contributing factors in SCT leading to severe ocular complications. This is one of the young patients with spontaneous vascular occlusion in SCT. PMID:25624687

  9. Central retinal artery occlusion following severe blow-out fracture in young adult

    Directory of Open Access Journals (Sweden)

    Noriko Himori

    2009-04-01

    Full Text Available Noriko Himori, Hiroshi Kunikata, Takaaki Otomo, Nobuo Fuse, Kohji NishidaDepartment of Ophthalmology and Visual Science, Tohoku University Graduate School of Medicine, Sendai, JapanAbstract: A 20-year-old woman was involved in a traffic accident while riding a motorcycle. The vision in her right eye was severely reduced. At the first examination, the eyelids of her right eye were severely swollen, and the eye could barely be seen. The fundus was not visible. She had no light perception in her vision. Computed tomography revealed a severe blow-out fracture in her right eye. Surgery was immediately performed to correct the fracture and the eye globe was replaced in the orbit. On the fourth postoperative day, the right fundus was visible and a cherry-red spot and milky-white edema were seen. Fluorescein angiography showed an arterial filling defect. Four months later, her visual acuity was light perception. Our case shows that a central retinal artery occlusion can be a complication of a blow-out fracture of the lower orbital wall and can lead to severe visual loss even with early surgical repair.Keywords: central retinal artery occlusion, blow out fracture, trauma, young adult

  10. 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.)

  11. Bilateral central retinal artery occlusion in a patient with systemic lupus erythematosus.

    Science.gov (United States)

    Hua, Li; Patel, Ketan; Corbett, James J

    2015-06-01

    Systemic lupus erythematosus (SLE) is associated with a wide range of ocular manifestations. We report a case of a 20-year-old woman with newly diagnosed SLE, who awoke with bilateral simultaneous central retinal artery occlusion (CRAO). Her antiphospholipid antibody panel was normal. Vision did not recover after treatment with steroids and anticoagulation. This case suggests that such patients may be in hypercoagulable status even with negative antiphospholipid antibodies. Severe ocular complication such as CRAO may occur during the early disease process. It is important to recognize this potential risk factor and treat vigorously and early. PMID:25906934

  12. Central retinal artery occlusion in the 9 years old girl (Clinical case report

    Directory of Open Access Journals (Sweden)

    E. Yu. Markova

    2014-07-01

    Full Text Available 9 years old girl was admitted to the Ophthalmological Department of Morozov Pediatric City Clinical Hospital with sudden persistent painless loss of vision of the left eye. Other organs and systems were without any changes. After ophthalmological examination (OS — white edema of central and peripapillar retina, a cherry red spot at the fovea the diagnosis of central retinal artery occlusion OS was formed, and treatment was started immediately. CRAO practically does not occur in pediatric ophthalmological practice. Therefore this clinical case can be of interest to clinicians and pediatric ophthalmologists.

  13. A simple model of oxygen diffusion out of the retinal artery

    Science.gov (United States)

    Beach, J. M.; Ning, J.; Khoobehi, B.; Rice, D. A.

    2009-02-01

    The purpose of this study is to explore the possibility that oxygen (O2) diffusion out of the retinal artery (RA) can explain the observed significant (Poxygen saturation (O2Sat) in RA as intraocular pressure (IOP) is raised from 10 to 55 mmHg. Hyperspectral image data from normal monkeys' optic nerve head (ONH) and overlying retinal blood vessels were recorded at IOP settings of 10, 30, 45 and 55 mmHg. Average percent O2Sat values of the RAs were found from the recorded blood spectra by comparing to reference spectra from saturated and desaturated red cell suspensions. Percent O2Sat of the RAs was 78.9% at IOP of 10 mmHg. This decreased to 74.1% at 45 mmHg (P=0.01); and further decreased to 51.5% at IOP = 55 mmHg (Poxygen tension (PO2). O2 flux across the arterial wall was calculated by Fick's law. The percentage of O2 diffusing out of the RA were 0.6% at IOP of 10 mmHg, and 38% at IOP of 55 mmHg. Confirmation still requires measurement of blood velocity.

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

    OpenAIRE

    Marmor Alon; Assy Nimer; Prober Ariel; Ibrahim Ali; Pikkel Josef

    2013-01-01

    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...

  16. Retinal vein occlusion

    Science.gov (United States)

    Central retinal vein occlusion; Branch retinal vein occlusion; CRVO; BRVO ... Retinal vein occlusion is most often caused by hardening of the arteries ( atherosclerosis ) and the formation of a blood clot. Blockage ...

  17. 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

  18. 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.

  19. Bilateral central retinal arterial obstruction following head trauma: A very rare case report

    Directory of Open Access Journals (Sweden)

    Ghose Saumendranath

    2011-01-01

    Full Text Available A 30-year-old patient presented at our outpatient department with complaints of severe loss of vision in both eyes following a head injury six days back. He also had a fracture at left side of the mandible and a few bruises over the left cheek. External ocular examination revealed subconjuctival hemorrhage in the left eye and bilateral sluggishly reacting pupils. Fundus examination showed white- out retina and a cherry red spot at the macula in both eyes. A clinical diagnosis of bilateral central retinal arterial obstruction (CRAO was made which was later confirmed by fundus fluorescence angiography. Bilateral CRAO is a rare disease usually found in patients with cardiac embolic diseases, giant cell arteritis or systemic vascular inflammations. Our case is the second reported case in English literature of bilateral CRAO following head trauma.

  20. 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.

  1. Obstrucción de rama macular de arteria central de la retina Occlusion of the macular branch of the central retinal artery

    Directory of Open Access Journals (Sweden)

    Jorge Orellana R

    2002-01-01

    Full Text Available We report a 54 years old female on oral anticoagulant treatment with a mitral valve disease, with a history of two transient ischemic attacks and a decreased visual acuity. She was assessed by an ophthalmologist and signs of retinal vascular disease were found. During follow up, the patient experienced an acute unilateral loss of vision in the left eye. Fundoscopy revealed an obstruction of a macular branch of central retinal artery. Aspirin was added to oral anticoagulants and one month later, the patient experienced an upper gastrointestinal bleeding. After four months of follow up, there is no recovery of left eye vision (Rev Méd Chile 2002; 130: 86-89

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

    DEFF Research Database (Denmark)

    Gesslein, Bodil; Håkansson, Gisela

    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.

  3. 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.

  4. FDG PET findings of the brain in sudden blindness caused by bilateral central retinal artery occlusion revealing giant cell arteritis.

    Science.gov (United States)

    Dietemann, Sébastien; Noblet, Vincent; Imperiale, Alessio; Blondet, Cyrille; Namer, Izzie Jacques

    2015-01-01

    We report the case of a 73-year-old woman presenting sudden blindness caused by bilateral simultaneous central retinal artery occlusion revealed by ophthalmoscopy. Temporal artery biopsy confirmed the giant cell arteritis. The patient was treated with a systemic steroid without visual recovery. FDG PET/CT was performed 6 months later in the context of persistent inflammatory syndrome. This case shows the close relationship between functional activity and glucose energy metabolism. We observed both bilateral occipital hypometabolism corresponding to loss of functional activity and bilateral temporal (auditory areas) and orbitofrontal hypermetabolism related to compensatory neuronal plasticity. PMID:25275418

  5. Retina derived relaxation is mediated by K(ir) channels and the inhibition of Ca(2+) sensitization in isolated bovine retinal arteries.

    Science.gov (United States)

    Tak?r, Selçuk; Uyde?-Do?an, B Sönmez; Özdemir, Osman

    2015-03-01

    Retinal relaxing factor (RRF) has recently been identified as a novel paracrine regulator of retinal circulation acting differently from well known mediators of the endothelium and the retina. Herein, we aimed to characterize the relaxing mechanism of the retina, i.e. RRF, by evaluating the role of Ca(+2)-dependent and -independent signaling mechanisms as well as inward rectifier K(+) (Kir) channels. Retinal relaxation was determined by placing a piece of retinal tissue just on top of the precontracted bovine retinal arteries mounted in a wire myograph. The retina produced a complete relaxation response, which display a biphasic character, in depolarized arteries contracted by L-type Ca(2+) channel agonist, Bay k 8644. Blockade of L-type Ca(2+) channel by nifedipine, inhibition of sarcoplasmic reticulum Ca(2+)-ATPase by cyclopiazonic acid or removal of extracellular Ca(2+) did not influence the prominent relaxation to the retina. Originally, retinal relaxation was found to be unaffected from the inhibition of myosin light chain kinase by ML7, whereas, completely abolished in the presence of myosin light chain phosphatase (MLCP) inhibitor, Calyculin A. Moreover, the inhibition of Rho kinase by its putative inhibitor, Y-27632 displayed comparable relaxant effects to RRF in retinal arteries precontracted either by prostaglandin F2? or K(+), and augmented the moderate response to the retina in K(+) precontracted arteries. In addition, retinal relaxation was significantly inhibited and lost its biphasic character in the presence of Kir channel blocker, Ba(2+). Our results suggested that inhibition of Ca(2+) sensitization through the activation of MLCP, possibly via interfering with Rho kinase, and the opening of Kir channels are likely to be involved in the inhibitory influence of RRF on the retinal arteries. PMID:25662314

  6. Accessory splenic artery from left gastroepiploic artery

    Directory of Open Access Journals (Sweden)

    Padmalatha K

    2010-08-01

    Full Text Available Splenic artery is the largest branch of celiac axis and its course is among the most tortuous in the body. We describe a rare variation of accessory splenic artery originating from the left gastroepiploic artery. Knowledge of variations of splenic artery is essential to successfully accomplish surgical, oncologic or any interventional procedures.

  7. Changes in central retinal artery blood flow after ocular warming and cooling in healthy subjects

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    Shamshad M

    2010-01-01

    Full Text Available Context: Retinal perfusion variability impacts ocular disease and physiology. Aim: To evaluate the response of central retinal artery (CRA blood flow to temperature alterations in 20 healthy volunteers. Setting and Design: Non-interventional experimental human study. Materials and Methods: Baseline data recorded: Ocular surface temperature (OST in °C (thermo-anemometer, CRA peak systolic velocity (PSV and end diastolic velocity (EDV in cm/s using Color Doppler. Ocular laterality and temperature alteration (warming by electric lamp/cooling by ice-gel pack were randomly assigned. Primary outcomes recorded were: OST and intraocular pressure (IOP immediately after warming or cooling and ten minutes later; CRA-PSV and EDV at three, six and nine minutes warming or cooling. Statistical Analysis: Repeated measures ANOVA. Results: (n = 20; ?±SD: Pre-warming values were; OST: 34.5±1.02°C, CRA-PSV: 9.3±2.33cm/s, CRA-EDV: 4.6±1.27cm/s. OST significantly increased by 1.96°C (95% CI: 1.54 to 2.37 after warming, but returned to baseline ten minutes later. Only at three minutes, the PSV significantly rose by 1.21cm/s (95% CI: 0.51to1.91. Pre-cooling values were: OST: 34.5±0.96°C, CRA-PSV: 9.7±2.45 cm/s, CRA-EDV: 4.7±1.12cm/s. OST significantly decreased by 2.81°C (95% CI: -2.30 to -3.37 after cooling, and returned to baseline at ten minutes. There was a significant drop in CRA-PSV by 1.10cm/s (95% CI: -2.05 to -0.15 and CRA-EDV by 0.81 (95% CI: -1.47 to -0.14 at three minutes. At six minutes both PSV (95% CI: -1.38 to -0.03 and EDV (95% CI: -1.26 to -0.02 were significantly lower. All values at ten minutes were comparable to baseline. The IOP showed insignificant alteration on warming (95% CI of difference: -0.17 to 1.57mmHg, but was significantly lower after cooling (95% CI: -2.95 to -4.30mmHg. After ten minutes, IOP had returned to baseline. Conclusion : This study confirms that CRA flow significantly increases on warming and decreases on cooling, the latter despite a significant lowering of IOP.

  8. NaHS induces relaxation response in prostaglandin F(2?) precontracted bovine retinal arteries partially via K(v) and K(ir) channels.

    Science.gov (United States)

    Tak?r, S; Ortaköylü, G Z; Toprak, A; Uyde?-Do?an, B S

    2015-03-01

    Hydrogen sulphide (H2S) is known to be produced endogenously in ocular tissues with the highest levels in the retina and cornea. However, it is yet unclear whether it can modulate retinal arterial tone. Herein, we aimed to investigate the effectiveness and the mechanism of the action of H2S in the isolated bovine retinal arteries. For this purpose, the probable vasorelaxant and inhibitory effects of H2S on vascular reactivity were tested comparatively in the retinal arteries by using the donor, sodium hydrosulphide (NaHS). Thereafter, in relation to the mechanism of action of H2S, the role of nitric oxide (NO) and endothelial vasodilators of cyclooxygenase pathway as well as ATP-sensitive potassium channel (KATP), voltage-dependent potassium channel (Kv), calcium-activated potassium channel (KCa(++)), inwardly rectifying potassium channel (Kir), L-type voltage-dependent calcium channel and adenylate cyclase pathway were evaluated. NaHS (1?M-3mM) displayed prominent relaxations over the concentrations of 300 ?M in both PGF2? and K(+) precontracted retinal arteries. Comparatively, in the presence of NaHS (3 mM) pretreatment, the maximum contractile responses and pEC50 values to PGF2? and K(+) were significantly reduced as well. Neither the presence of the known inhibitors of NO synthase, guanylate cyclase, cyclooxygenase, adenylate cyclase, KATP and KCa(++) type K(+) channels, and L-type voltage-dependent calcium channels nor the removal of endothelium, modified the relaxation response to NaHS in retinal arteries. However, a remarkable decrease was observed in the presence of the inhibitors of Kv or Kir type K(+) channels. In addition, administration of l-cysteine (1?M-3mM), the precursor of H2S, induced a modest relaxation response in PGF2? precontracted retinal arteries, which was significantly decreased in the presence of cystathionine-?-synthase (CBS) inhibitor, aminooxyacetic acid, but was unmodified in the presence of the cystathionine-?-lyase (CSE) inhibitor, dl-propargylglycine or the deendothelization of retinal arteries. Our findings suggested that H2S might play a substantial role in the regulation of retinal arterial tone possibly by acting on Kv and Kir channels. PMID:25662313

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

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    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.

  10. HIGH DIVISION ABDOMINAL AORTA WITH TORTUOUS ILIAC ARTERIES

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    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.

  11. Tomografía óptica de coherencia en oclusión de arteria central de la retina Optical coherence tomography in central retinal artery occlusion

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    A. Salinas-Alamán

    2006-09-01

    Full Text Available Casos clínicos: Presentamos tres ojos afectados de obstrucción de arteria central de la retina (OACR. En todos ellos realizamos exploración con tomografía óptica de coherencia (OCT. Dependiendo del tiempo de evolución del cuadro clínico, los signos oftalmoscópicos de OACR eran más o menos evidentes. Sin embargo, la presencia de una banda hiporreflectante en las imágenes de OCT pudo objetivarse en todos los casos. Discusión: La presencia en las imágenes de OCT de una banda hiporreflectante por debajo de la retina neurosensorial en los casos de OACR, que persiste incluso meses después del inicio del cuadro clínico, resulta útil en el diagnóstico de esta patología retiniana.Clinical cases: Three eyes with central retinal artery occlusion (CRAO have been studied. Optical coherence tomography (OCT was performed in each of them. Ophthalmoscopic signs of CRAO were equivocal in the three eyes. However, the presence of a hyporeflective signal in the OCT scan could be seen clearly in each of them. Discussion: The presence of a hyporeflective band between the neurosensory retina and the retinal pigment epithelium in OCT images, that persist for several months after a CRAO episode, is useful in establishing the diagnosis in these patients.

  12. 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.

  13. 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.

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

    Directory of Open Access Journals (Sweden)

    Marco Aurélio Martins de Souza

    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.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 tibolone (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(post0.72±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.

  15. Central retinal artery occlusion associated with traumatic carotid cavernous fistula: case report Oclusão de artéria central da retina associada com fístula carótido-cavernosa traumática: relato de caso

    OpenAIRE

    Paulo de Tarso Ponte Pierre Filho; Flavio Mac Cord Medina; Fabrício Kafury Pereira Rodrigues; Clayton Rocha Lara Carrera

    2007-01-01

    Carotid cavernous fistulas are a rare entity occurring as result of head trauma and also spontaneously. The authors report a rare case of central retinal artery occlusion complicating traumatic carotid-cavernous fistula, resulting in severe visual acuity loss. Spontaneous closure of the fistula was observed. The possible mechanisms responsible for this complication are discussed.Fístulas carótido-cavernosas são raras e ocorrem como resultado de trauma cefálico e também espontaneamente. O...

  16. Síndrome do anticorpo antifosfolípide causando oclusão bilateral de artérias e veias centrais da retina: relato de caso / Antiphospholipid syndrome and bilateral retinal artery and vein occlusion: case report

    Scientific Electronic Library Online (English)

    Ana Paula, Beckhauser; Luís Augusto, Arana; Thelma Larocca, Skare.

    2008-04-01

    Full Text Available A síndrome do anticorpo antifosfolípide (SAF) tem sido associada a trombose de vasos arteriais e periféricos e de grande ou pequeno calibre. Também os vasos oculares estão sujeitos à ação destes auto-anticorpos que podem promover o aparecimento de perda visual transitória, diplopia, neuropatia óptic [...] a isquêmica e oclusão de artéria ou veia da retina. É descrito aqui, um caso de síndrome do anticorpo antifosfolípide com oclusão de vasos centrais arteriais e venosos da retina no intuito de chamar a atenção para este tipo de diagnóstico. Abstract in english The antiphospholipid syndrome (APS) has been related to venous and arterial thrombosis of large and small vessels. Ocular vessels can also be involved causing transient visual loss, diplopia, ischemic optic neuropathy and central artery and venous occlusion. We describe here a case of antiphospholip [...] id syndrome with occlusion of central retinal artery and vein to call the attention to this diagnosis.

  17. A case report and brief review of the literature on bilateral retinal infarction following cardiopulmonary bypass for coronary artery bypass grafting

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    Trethowan Brian A

    2011-11-01

    Full Text Available Abstract Postoperative visual loss is a devastating perioperative complication. The commonest aetiologies are anterior ischaemic optic neuropathy (AION, posterior ischaemic optic neuropathy (PION, and central retinal artery occlusion (CRAO. These appear to be related to certain types of operation, most commonly spinal and cardiac bypass procedures; with the rest divided between: major trauma causing excessive blood loss; head/neck and nasal or sinus surgery; major vascular procedures (aortic aneurysm repair, aorto-bifemoral bypass; general surgery; urology; gynaecology; liposuction; liver transplantation and duration of surgery. The non-surgical risk factors are multifactorial: advanced age, prolonged postoperative anaemia, positioning (supine v prone, alteration of venous drainage of the retina, hypertension, smoking, atherosclerosis, hyperlipidaemia, diabetes, hypercoagulability, hypotension, blood loss and large volume resuscitation. Other important cardiac causes are septic emboli from bacterial endocarditis and emboli caused by atrial myxomata. The majority of AION cases occur during CPB followed by head/neck surgery and prone spine surgery. CPB is used to allow coronary artery bypass grafting on a motionless heart. It has many side-effects and complications associated with its use and we report here a case of bilateral retinal infarction during routine coronary artery bypass grafting in a young male patient with multiple risk factors for developing this complication despite steps to minimise its occurrence.

  18. 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.

  19. 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.

  20. Retinal blood flow evaluation.

    Science.gov (United States)

    Pournaras, Constantin J; Riva, Charles E

    2013-01-01

    Much of our basic knowledge of retinal blood flow regulation is based on data obtained from animal experiments through the use of invasive techniques. However, during the last decades, major developments in the field of optics and lasers have led to a variety of noninvasive techniques, which have been applied to the human eye for the investigation of retinal hemodynamics, and more specifically the regulation of retinal blood flow in response to a number of physiological and pharmacological stimuli. The Retinal Vessel Analyzer has markedly simplified the measurement of the diameter of retinal vessels, as well as the change in this diameter evoked by various physiological stimuli (dynamic measurements). Bidirectional laser Doppler velocimetry allows the measurement of absolute red blood cell centerline velocity, which, when combined with the diameter allows the calculation of retinal blood flow in the main retinal vessels. Laser Doppler flowmetry and laser speckle flowgraphy are techniques that measure the velocities of blood in discrete areas of the retinal tissue microcirculation. Adding a scanning capability, a spatial map of velocities across the retinal tissue is obtained. The blue-field simulation technique allows the quantification of the velocity, number and velocity pulsatility of leukocytes moving in the retinal capillaries of the macular region. With color Doppler imaging, the peak systolic and end-diastolic values of blood velocity in the ophthalmic and central retinal artery are measured, from which a resistivity index is obtained. These techniques may help better understand the role of altered retinal blood flow and its regulation in the pathogenesis of retinal diseases of vascular origin. PMID:23257770

  1. Central retinal artery occlusion associated with traumatic carotid cavernous fistula: case report Oclusão de artéria central da retina associada com fístula carótido-cavernosa traumática: relato de caso

    Directory of Open Access Journals (Sweden)

    Paulo de Tarso Ponte Pierre Filho

    2007-10-01

    Full Text Available Carotid cavernous fistulas are a rare entity occurring as result of head trauma and also spontaneously. The authors report a rare case of central retinal artery occlusion complicating traumatic carotid-cavernous fistula, resulting in severe visual acuity loss. Spontaneous closure of the fistula was observed. The possible mechanisms responsible for this complication are discussed.Fístulas carótido-cavernosas são raras e ocorrem como resultado de trauma cefálico e também espontaneamente. Os autores relatam um caso raro de oclusão de artéria central da retina complicando fístula carótido-cavernosa traumática, resultando em perda grave da acuidade visual. Fechamento espontâneo da fístula foi observado. Os possíveis mecanismos responsáveis por esta complicação são discutidos.

  2. Central retinal artery occlusion associated with traumatic carotid cavernous fistula: case report / Oclusão de artéria central da retina associada com fístula carótido-cavernosa traumática: relato de caso

    Scientific Electronic Library Online (English)

    Paulo de Tarso Ponte, Pierre Filho; Flavio Mac Cord, Medina; Fabrício Kafury Pereira, Rodrigues; Clayton Rocha Lara, Carrera.

    2007-10-01

    Full Text Available Fístulas carótido-cavernosas são raras e ocorrem como resultado de trauma cefálico e também espontaneamente. Os autores relatam um caso raro de oclusão de artéria central da retina complicando fístula carótido-cavernosa traumática, resultando em perda grave da acuidade visual. Fechamento espontâneo [...] da fístula foi observado. Os possíveis mecanismos responsáveis por esta complicação são discutidos. Abstract in english Carotid cavernous fistulas are a rare entity occurring as result of head trauma and also spontaneously. The authors report a rare case of central retinal artery occlusion complicating traumatic carotid-cavernous fistula, resulting in severe visual acuity loss. Spontaneous closure of the fistula was [...] observed. The possible mechanisms responsible for this complication are discussed.

  3. Transcorneal Electrical Stimulation Therapy for Retinal Disease

    Science.gov (United States)

    2012-05-03

    Retinitis Pigmentosa; Macula Off; Primary Open Angle Glaucoma; Hereditary Macular Degeneration; Treated Retina Detachment; Retinal Artery Occlusion; Retinal Vein Occlusion; Non-Arthritic-Anterior-Ischemic Optic-Neuropathy; Hereditary Autosomal Dominant Optic Atrophy; Dry Age Related Macular Degeneration; Ischemic Macula Edema

  4. Effect of red blood cells on platelet activation and thrombus formation in tortuous arterioles

    Directory of Open Access Journals (Sweden)

    Hai-ChaoHan

    2013-12-01

    Full Text Available Thrombosis is a major contributor to cardiovascular disease, which can lead to myocardial infarction and stroke. Thrombosis may form in tortuous microvessels, which are often seen throughout the human body, but the microscale mechanisms and processes are not well understood. In straight vessels, the presence of red blood cells (RBCs is known to push platelets toward walls, which may affect platelet aggregation and thrombus formation. However in tortuous vessels, the effects of RBC interactions with platelets in thrombosis are largely unknown. Accordingly, the objective of this work was to determine the physical effects of RBCs, platelet size, and vessel tortuosity on platelet activation and thrombus formation in tortuous arterioles. A discrete element computational model was used to simulate the transport, collision, adhesion, aggregation, and shear-induced platelet activation of hundreds of individual platelets and RBCs in thrombus formation in tortuous arterioles. Results showed that high shear stress near the inner sides of curved arteriole walls activated platelets to initiate thrombosis. RBCs initially promoted platelet activation, but then collisions of RBCs with mural thrombi reduced the amount of mural thrombus and the size of emboli. In the absence of RBCs, mural thrombus mass was smaller in a highly tortuous arteriole compared to a less tortuous arteriole. In the presence of RBCs however, mural thrombus mass was larger in the highly tortuous arteriole compared to the less tortuous arteriole. As well, smaller platelet size yielded less mural thrombus mass and smaller emboli, either with or without RBCs. This study shed light on microscopic interactions of RBCs and platelets in tortuous microvessels, which have implications in various pathologies associated with thrombosis and bleeding.

  5. 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...

  6. A tortuous proximal urethra in urorectal septum malformation sequence?

    Science.gov (United States)

    Lin, Henry J; Lugo, Hector; Tran, Thu; Tovar, Jason P; Corral, Julia; Zork, Noelia M; Smith, Lynne M; French, Samuel W; Barajas, Luciano

    2014-05-01

    We observed a newborn boy with urorectal septum malformation sequence. Anomalies of the genitalia and rectum were present. He expired on the first day of life, due to severe lung hypoplasia. Autopsy showed a colon that ended in a blind sac, an enlarged bladder with no grossly visible urethra, and dysplastic kidneys. A cone-shaped tissue at the usual site of the bladder outlet contained tortuous and slit-like lumina, suggesting an undeveloped proximal urethra. The urethral structure was lined by transitional epithelium with squamous metaplasia. Many small buds-lined with columnar epithelium-branched from the urethral structure. These ductal buds lined with columnar epithelium stained for prostatic acid phosphatase. Basal cells surrounding the ductal buds stained for p63 and high molecular weight cytokeratin-supporting an interpretation that the buds were early prostatic ducts with normal histology. To our knowledge, these are the first histological images of an undeveloped, obstructed urethra associated with the urorectal septum malformation sequence. PMID:24665006

  7. Cytomegalovirus retinitis

    Science.gov (United States)

    CMV retinitis ... CMV retinitis is caused by a member of a group of herpes-type viruses. CMV is very common. Most ... Some people with CMV retinitis have no symptoms. Symptoms include: ... vision problems Floaters Retinitis usually begins in one eye, ...

  8. 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.

  9. 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.

  10. 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)

  11. 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.

  12. Imaging of a Cilioretinal Artery Embolisation

    Directory of Open Access Journals (Sweden)

    Marion R. Munk

    2014-09-01

    Full Text Available Retinal artery occlusion can be the first indicator of a significant cardiovascular disorder and the need for treatment. We present the case of a 69-year-old man with a cilioretinal artery occlusion and retinal ischemia. Retinal imaging, in particular fundus autofluorescence, highlighted an intraluminal hyperautofluorescent lesion which led to the diagnosis of retinal emboli. Subsequently a severe, previously undiagnosed carotid occlusive disease was discovered. The patient underwent prompt endarterectomy.

  13. Retinal flow cytometer

    OpenAIRE

    Alt, C.; Veilleux, I.; Lee, H.; Pitsillides, C. M.; Co?te?, D.; Lin, C. P.

    2007-01-01

    The in vivo flow cytometer is an instrument capable of continuous, real-time monitoring of fluorescently labeled cells in the circulation without the need to draw blood samples. However, the original system probes a single vessel in the mouse ear; the small sample volume limits the sensitivity of the technique. We describe an in vivo retinal flow cytometer that simultaneously probes five artery–vein pairs in the mouse eye by circularly scanning a small laser spot rapidly around the optic ne...

  14. Foveomacular retinitis.

    OpenAIRE

    Kuming, B. S.

    1986-01-01

    A group of patients is described who developed the clinical features of foveomacular retinitis. No causative factors were isolated, and all patients strongly denied any type of sun gazing. It is possible that there is a group of patients who have the features of foveomacular retinitis but have not had any direct exposure to the sun. These patients would then constitute a primary type of foveomacular retinitis, as opposed to a secondary type which has a known cause and is synonymous with solar...

  15. Buckling instability in arteries.

    Science.gov (United States)

    Vandiver, Rebecca M

    2015-04-21

    Arteries can become tortuous in response to abnormal growth stimuli, genetic defects and aging. It is suggested that a buckling instability is a mechanism that might lead to artery tortuosity. Here, the buckling instability in arteries is studied by examining asymmetric modes of bifurcation of two-layer cylindrical structures that are residually stressed. These structures are loaded by an axial force, internal pressure and have nonlinear, anisotropic, hyperelastic responses to stresses. Strain-softening and reduced opening angle are shown to lower the critical internal pressure leading to buckling. In addition, the ratio of the media thickness to the adventitia thickness is shown to have a dramatic impact on arterial instability. PMID:25661070

  16. Techniques for passing the PercuSurge Guardwire system through severe and tortuous stenotic lesions.

    Science.gov (United States)

    Satow, Tetsu; Nakazawa, Kazutomo; Ohta, Tsuyoshi; Hashimoto, Nobuo

    2005-02-01

    Distal embolism is one of the major causes of morbidity and mortality associated with treating stenotic lesions by endovascular procedures, such as percutaneous angioplasty and stenting. Many devices have been designed and used to prevent this complication. The PercuSurge Guardwire system is recognized as the best system available to prevent distal embolism during stenting. However, this system is sometimes hard to pass through severe stenotic, tortuous lesions because of the poor selectivity and support. The PercuSurge device was safely introduced into two cases of severe stenotic and tortuous lesions with a triple coaxial system and the buddy wire technique, and stenting was performed successfully. These techniques are very helpful for introducing and maintaining this system in the correct position across stenoses with unfavorable configurations. PMID:15722613

  17. Constitutive Modeling of Anisotropic Finite-Deformation Hyperelastic Behaviors of Soft Materials Reinforced by Tortuous Fibers

    OpenAIRE

    Kao, Philip H.; Lammers, Steven R.; Hunter, Kendall; Stenmark, Kurt R.; Shandas, Robin; Qi, H. Jerry

    2010-01-01

    Many biological materials are composites composed of a soft matrix reinforced with stiffer fibers. These stiffer fibers may have a tortuous shape and wind through the soft matrix. At small material deformation, these fibers deform in a bending mode and contribute little to the material stiffness; at large material deformation, these fibers deform in a stretching mode and induce a stiffening effect in the material behavior. The transition from bending mode deformation to stretching mode deform...

  18. [Retinal tubulation].

    Science.gov (United States)

    Matušková, V

    2015-01-01

    The aim of this study is to present a new retinal structure which is detectable on OCT scans - outer retinal tubulations (ORT). The discovery of these structures is related to more and more perfect retinal imaging using the spectral domain optical coherence tomography (SD OCT). Outer retinal tubulations were first described by Zweifel et al. in the year 2009 in patients with age-related macular degeneration. These branching tubular structures are localized in the outer nuclear layer of the retina. They are of circular or ovoid shape, with hyporeflectivity in the center, their borders are hyperreflective. Retinal tubulations are mostly seen together with choroid neovasculare membrane or with retinal pigment epithelium atrophy. Typically, they are adjacent to the area of wide damage of the outer retinal structure combined with relatively good preserved photoreceptor layer (respectively junctions between inner and outer photoreceptors segments), often they overlap the area of subretinal fibrosis or RPE (retinal pigment epithelium) damage. In eyes with anti-VEGF (vascular endothelial growth factor) treatment, they do appear in the area, where, before the treatment, the intraretinal fluid was present. These structures may simulate CME or the presence of subretinal fluid, so their determination plays an important role in the indications of next anti-VEGF drugs applications. Their non-detection may cause unneeded re-applications of anti-VEGF drugs into the viterous. This study was presented as a lecture at the Congress of the Czech VitreoRetinal Society in Dolní Morava (Czech Republic, E.U.) in the year 2014.Key words: outer retinal tubulations (ORT), cystoid macular edema (CME), age-related macular degeneration (ARMD), optical coherence tomography (OCT). PMID:25962420

  19. Effects of elastic and inelastic scattering in giving electrons tortuous paths in matter.

    Science.gov (United States)

    Turner, J E; Hamm, R N

    1995-09-01

    Heavy charged particles travel in essentially straight lines in matter, while electrons travel in tortuous paths. Frequent multiple elastic Coulomb scattering by atomic nuclei is often cited as the reason for this electron behavior. Heavy charged particles also undergo multiple Coulomb scattering. However, because they are massive, significant deflections occur only in rare, close encounters with nuclei. In contrast to heavy particles, the inelastic interaction of an electron with an atomic electron represents a collision with a particle of equal mass. In principle, therefore, repeated inelastic scattering of an electron can also produce large-angle deflections and thus contribute to the tortuous nature of an electron's track. To investigate the relative importance of elastic and inelastic scattering on determining the appearance of electron tracks, detailed Monte Carlo transport computations have been carried out for monoenergetic pencil beams of electrons normally incident on a water slab with initial energies from 1 keV to 1 MeV. The calculations have been performed with deflections due to (1) inelastic scattering only, (2) elastic scattering only, and (3) both types of scattering. Results are presented to show the spreading of the pencil beams with depth in the slab, the transmission through slabs of different thicknesses, and back-scattering from the slab. The results show that elastic nuclear scattering is indeed the principal physical process that causes electron paths to be tortuous; however, the smaller effect of inelastic electronic scattering is far from negligible. PMID:7635734

  20. Retinal pigment epithelial fine structure in the bobtail goanna (Tiliqua rugosa)

    OpenAIRE

    Braekevelt, Charlie R.

    1989-01-01

    The retinal pigment'epithelium (RPE), the choriocapillaris and Bruch's membrane (complexus basalis) have been studied by light and electron microscopy in the bobtail goanna (Tiliqua rugosa) an Australian diurna1 lizard. The RPE consists of a single layer of cuboidal cells which display very deep and tortuous basal (choroidal) infoldings as well as numerous apical (vitreal) processes which interdigitate with the photoreceptor cells. The lateral cell borders are ...

  1. 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

  2. An anatomical study of double brachial arteries – a case report

    Directory of Open Access Journals (Sweden)

    Krstonosic B

    2010-02-01

    Full Text Available Superficial brachial artery is one of the major variations of the arterial pattern in the upper limb. During routine anatomical dissection in our department, we observed a case of unilateral double brachial artery in a formalin-fixed female cadaver.Left axillary artery entered into the anterior region of the arm, where it branched into two brachial arteries – the superficial brachial artery (SBA, which was longer, tortuous and with a smaller caliber, and the brachial artery (BA, which was placed deep and medially. In the cubital fossa, covered with an aponeurosis of the biceps brachii muscle, both brachial arteries were connected with an anastomotic vessel. Under this anastomotic branch, in the forearm, SBA continued as the radial artery, whereas BA continued as the ulnar artery.Variations of the arterial pattern in the upper limb are undoubtedly of interest to the anatomists as well as to the clinicians.

  3. Retinal vessel oximetry: toward absolute calibration

    Science.gov (United States)

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

    2000-06-01

    Accurately measuring the oxygen saturation of blood within retinal arteries and veins has proven to be a deceptively difficult task. Despite the excellent optical accessibility of the vessels and a wide range of reported instrumentation, we are unaware of any measurement technique that has proven to be calibrated across wide ranges of vessel diameter and fundus pigmentation. We present an overview of our retinal oximetry technique, present the results of an in vitro calibration experiment, and present preliminary human data.

  4. 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.

  5. Retinal leukocyte behavior in experimental autoimmune uveoretinitis of rats.

    Science.gov (United States)

    Hamada, M; Ogura, Y; Miyamoto, K; Nishiwaki, H; Hiroshiba, N; Honda, Y

    1997-09-01

    In vivo retinal leukocyte behavior in the experimental autoimmune uveoretinitis (EAU) of rats was investigated using acridine orange digital fluorography. The technique employed high resolution images obtained from a scanning laser ophthalmoscope (SLO) subsequent to staining with the fluorescent nuclear dye, acridine orange. Two weeks after immunization with synthetic peptides of retinal soluble antigen (S-Ag), acridine orange was intravenously injected, and fundus images were generated by SLO. Many rolling leukocytes were observed along the venous walls as slowly moving fluorescent dots; moreover, leukocytes infiltrating into the vitreous cavity were also noted especially over the retinal veins, but not over the retinal arteries. In addition, major retinal vessels were significantly dilated. The diameters of the retinal veins at a distance of 1 disc diameter away from the center of the optic disc were 49.8+/-4.5 micron for the normal rats and 88.2+/-3.6 micron for the EAU rats, respectively (P<0.001). Similarly, the diameters of retinal arteries were 32.6+/-3.7 micron for the normal rats, 53.8+/-1.5 micron for the EAU rats, respectively (P<0.01). The dilation was more prominent in the veins than in the arteries. These results suggest that it is possible to visualize the retinal involvement of EAU in vivo. The results also suggest that leukocyte-endothelial interaction and extravascular infiltration in the retinal venous vasculature may play significant roles in the early stages of posterior segment inflammation in EAU. PMID:9299181

  6. Retinal Vascular Changes are a Marker for Cerebral Vascular Diseases.

    Science.gov (United States)

    Moss, Heather E

    2015-07-01

    The retinal circulation is a potential marker of cerebral vascular disease because it shares origin and drainage with the intracranial circulation and because it can be directly visualized using ophthalmoscopy. Cross-sectional and cohort studies have demonstrated associations between chronic retinal and cerebral vascular disease, acute retinal and cerebral vascular disease, and chronic retinal vascular disease and acute cerebral vascular disease. In particular, certain qualitative features of retinopathy, retinal artery occlusion, and increased retinal vein caliber are associated with concurrent and future cerebrovascular events. These associations persist after accounting for confounding variables known to be disease-causing in both circulations, which supports the potential use of retinal vasculature findings to stratify individuals with regards to cerebral vascular disease risk. PMID:26008809

  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 oximetry during ranibizumab treatment of central retinal vein occlusion

    DEFF Research Database (Denmark)

    Traustason, Sindri; la Cour, Morten

    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 in eyes with CRVO than in the fellow eyes (95%±8% and 91%±3%, p=0.04). Mean visual acuity increased from 51±24 letters ETDRS at baseline to 66±24 and 69±20 letters ETRDS, respectively, at 3 months and 6?months treatment (mean±SD, p<0.0001, repeated measures analysis of variance) and central retinal thickness was reduced from 697±139?µm to 368±113?µm and 340±96?µm, respectively, from baseline to 3 months and 6?months treatment (p<0.0001). Venous saturation increased during treatment (from 35.5%±13.8% at baseline to 43.1%±10.8% and 43.5%±13.7% after 3 months and 6 months treatment, respectively, p=0.012), 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 REGISTRATION NUMBER: NCT01360385.

  9. Acute Variations in Retinal Vascular Oxygen Content in a Rabbit Model of Retinal Venous Occlusion

    Science.gov (United States)

    Saati, Saloomeh; Martin, Gabriel; Chader, Gerald; Humayun, Mark S.

    2012-01-01

    Purpose To study the variation in intravascular oxygen saturation (oximetry) during an acute retinal vein occlusion (RVO) using hyperspectral computed tomographic spectroscopy based oximetry measurements. Methods Thirty rabbits were dilated and anesthetized for experiments. Baseline oximetry measurements were made using a custom-made hyperspectral computed tomographic imaging spectrometer coupled to a fundus camera. RVO were induced using argon green laser following an intravenous injection of Rose Bengal. RVO induction was confirmed by fluorescein angiography. Retinal oximetry measurements were repeated in arterial and venous branches one hour after RVO induction and up to 4 weeks afterwards. Comparison of retinal oximetry before and after vein occlusion was made using the Student T-test. Results One hour after RVO induction, we observed statistically significant reductions in the intravascular oxygen saturation in temporal retinal arteries (85.1±6.1% vs. 80.6±6.6%; p<0.0001) and veins (71.4±5.5% vs. 64.0±4.7%; p<0.0001). This decrease was reversible in animals that spontaneously recannulated the vein occlusion. There were no statistically significant differences in oxygen saturation in the nasal control arteries and veins before and after temporal vein RVO induction. Conclusions We demonstrate, for the first time, acute changes in the intravascular oxygen content of retinal vessels 1 hour after RVO. These changes are reversible upon spontaneous recannulation of retinal vessels. This study demonstrates that hyperspectral computer tomographic spectroscopy based oximetry can detect physiological variations in intravascular retinal oxygen saturation. The study also provides the first qualitative and quantitative evidence of the variation in retinal vascular oxygen content directly attributable to an acute retinal vein occlusion. PMID:23185567

  10. 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.

  11. Artery buckling stimulates cell proliferation and NF-?B signaling.

    Science.gov (United States)

    Xiao, Yangming; Hayman, Danika; Khalafvand, Seyed Saeid; Lindsey, Merry L; Han, Hai-Chao

    2014-08-15

    Tortuous carotid arteries are often seen in aged populations and are associated with atherosclerosis, but the underlying mechanisms to explain this preference are unclear. Artery buckling has been suggested as one potential mechanism for the development of tortuous arteries. The objective of this study, accordingly, was to determine the effect of buckling on cell proliferation and associated NF-?B activation in arteries. We developed a technique to generate buckling in porcine carotid arteries using long artery segments in organ culture without changing the pressure, flow rate, and axial stretch ratio. Using this technique, we examined the effect of buckling on arterial wall remodeling in 4-day organ culture under normal and hypertensive pressures. Cell proliferation, NF-?B p65, I?B-?, ERK1/2, and caspase-3 were detected using immunohistochemistry staining and immunoblot analysis. Our results showed that cell proliferation was elevated 5.8-fold in the buckling group under hypertensive pressure (n = 7, P < 0.01) with higher levels of NF-?B nuclear translocation and I?B-? degradation (P < 0.05 for both). Greater numbers of proliferating cells were observed on the inner curve side of the buckled arteries compared with the outer curve side (P < 0.01). NF-?B colocalized with proliferative nuclei. Computational simulations using a fluid-structure interaction model showed reduced wall stress on the inner side of buckled arteries and elevated wall stress on the outer side. We conclude that arterial buckling promotes site-specific wall remodeling with increased cell proliferation and NF-?B activation. These findings shed light on the biomechanical and molecular mechanisms of the pathogenesis of atherosclerosis in tortuous arteries. PMID:24929858

  12. Atypical twin renal arteries with altered hilar anatomy

    Directory of Open Access Journals (Sweden)

    Loh HK

    2009-10-01

    Full Text Available Twin renal arteries (superior and inferior were encountered on the left side in a 58-year-old male Indian cadaver. Both the renal arteries took a tortuous course to the hilum. The inferior renal artery, labeled as the accessory renal artery travelled sinuously and anteriorly over the left renal vein to enter the inferior most part of the hilum. The superior artery, labeled as main renal artery bifurcated before the hilum and its two branches were placed anterior to the vein. Thus the normal anteroposterior disposition of structures viz. renal vein, renal artery and the renal pelvis was not seen. Such renal arteries having sinuous course with atypical sequence of structures at the hilum are of worth concern to the urologists performing renal angiography and to surgeons performing laparoscopies or renal transplantation.

  13. 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.

  14. RX-08-HD, a low-viscosity, injection-moldable explosive for filling tortuous paths

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, D.M.; Jessop, E.S.; Swansiger, R.W.

    1997-10-01

    Cast cure, extrusion cast, and paste extrudable explosives have not been designed for transferring through long tortuous paths or into fine three dimensional shapes. To allow the crystalline explosive to flow a lubricating fluid is required. The energetic liquid ethane trinitrate (TMETN) was used as the lubricant to maximize the explosive energy. TMETN is a liquid nitrate ester which requires stabilization with conventional free radical stabilizers such as 2- nitrodiphenylamine, methyl-nitroanaline, or ethyl centrylite. Since these injection moldable explosives are expected to cure in place, a polyesterurethane binder based on polymeric isocyanate of hexamethylene diisocyanate and polycaprolactone polyols is dissolved in TMETN. The solubility of the polymer precursors in TMETN also reduces the energetic liquids sensitivity. The latent cure catalyst Dabco T-131 was used to minimize shrinkage associated with thermal expansion, reduce cost associated with oven cures, to give 4-6 hour potlife and overnight cure to handling strength. The product RX-08-HD is a new, low-viscosity, injection moldable explosive that can be extruded into complex, void-free shapes. Combined with appropriate design and other aspects of weaponization, RX-08-HD has produced outstanding results.

  15. Design of bi-tortuous, anisotropic graphite anodes for fast ion-transport in Li-ion batteries

    OpenAIRE

    Nemani, V. Pavan; Harris, Stephen J.; Smith, Kyle C.

    2015-01-01

    Thick electrodes in Li-ion batteries could enable low-cost vehicular energy-storage by reducing the costs stemming from inactive cell-components, and ion transport is the primary limiting process in dense, thick electrodes. Further, recent work has shown that anisotropy in ion transport through anodes composed of pressed graphite platelets can inhibit cycling more so than in other electrodes. Here, we predict that bi-tortuous electrode structures (containing electrolyte-rich...

  16. Interventional therapy of complications after liver transplantation: hepatic artery stricture

    International Nuclear Information System (INIS)

    Hepatic artery stricture (HAS) after liver transplantation can lead directly to transplanted liver function exhaustion and complications of biliary system. The early diagnosis and treatment are crucial for better prognosis. Doppler ultrasound is the first method of choice, and angiography can give further clear dignosis. The balloon dilatation is still effective for hepatic arterial stenosis. With the more adaptable usage of oronary stent, if possible, would reveal more promising result especially for tortuous stenotic hepatic artery. The vascular reconstruction or repeated liver transplantation is still the effective therapeutic methods. (authors)

  17. Recanalization of Splenic Artery Aneurysm After Transcatheter Arterial Embolization Using N-Butyl Cyanoacrylate

    International Nuclear Information System (INIS)

    A 65-year-old woman who had been diagnosed as having microscopic polyangiitis developed sudden abdominal pain and entered a state of shock. Abdominal CT showed massive hemoperitoneum, and emergent angiography revealed a ruptured splenic artery aneurysm. After direct catheterization attempts failed due to tortuous vessels and angiospasm, transcatheter arterial embolization using an n-butyl cyanoacrylate (NBCA)-lipiodol mixture was successfully performed. Fifty days later, the patient developed sudden abdominal pain again. Repeated angiography demonstrated recanalization of the splenic artery and splenic artery aneurysm. This time, the recanalized aneurysm was embolized using metallic coils with the isolation method. Physicians should keep in mind that recanalization can occur after transcatheter arterial embolization using N-butyl cyanoacrylate, which has been used as a permanent embolic agent.

  18. Use of ‘Guideliner’ catheter to overcome failure of delivery of Absorb™ Bioresorbable Vascular Scaffold in calcified tortuous coronary lesions: Technical considerations in ‘Real World Patients’

    OpenAIRE

    Seth, Ashok; Ravisekar, Vinayak; Kaul, U.

    2014-01-01

    In our series of 177 real world patients (223 lesions) who underwent Absorb Bioresorbable Vascular Scaffold (BVS) implantation, 78 lesions were calcified and tortuous lesions. In four of these, despite adequate lesion bed preparation, appropriate guiding catheter support and use of buddy wires, the BVS failed to track through the proximal calcified and tortuous coronary anatomy (CTCA). “Guide Liner” catheter (GLC) had to be finally used to resuccessfully deliver and implant BVS to the les...

  19. Generalized Local Cubic Law for inertial fluid flow and solute transport through tortuous and rough fractures

    Science.gov (United States)

    Wang, L.; Cardenas, M.; Slottke, D. T.; Ketcham, R. A.; Sharp, J. M.

    2013-12-01

    Fundamental understanding of flow and transport processes through single rough-walled fractures remains a challenge to gain insight for interpreting hydrological phenomena at continuum scale. The Generalized Local Cubic Law (GLCL) developed here is based on (1) modifying the aperture field by orienting it with the flow direction accounting for tortuosity, and (2) correcting for roughness changes associated with flow expansion/contraction and inertial effects. We compared its performance in estimating flow rate to results of direct numerical simulations with the Navier-Stokes equations (NSE) and physical flow experiments for real and synthetic three-dimensional rough-walled fractures. We also evaluated the performance of the Local Cubic Law (LCL). The LCL consistently overestimates flow rate with relative error ? ranging from 20% to 100% with arithmetic mean of |?| () equal to 45.4% depending on the degree of tortuosity and roughness. However, the GLCL performs well and improves the performance of the LCL, where ? in flow rate range from -3.1% to 11.4% with =4.7%. Furthermore, we generated breakthrough curves (BTCs) through direct numerical simulations based on the advection-diffusion equation with flow field resulting from solving the NSE (which are considered to the true or experimental BTCs). We revisited the applicability of random walk particle tracking (RWPT) to simulate solute transport dynamics through real fractures, where flow fields resulted from the GLCL and LCL, respectively. We found persistent early arrival and heavy tailing in the BTCs from both direct numerical simulations and RWPT, which are the salient characteristics of non-Fickian behavior. The LCL consistently overestimates mean flow velocity; whereas the GLCL improves estimating flow field, and markedly improves fits to the BTCs relative to those fitted with LCL solutions. Therefore, PWPT with flow field resulting from the GLCL is robust in predicting solute transport through tortuous and rough fractures.

  20. Central retinal vein occlusion resulting from anomalous retinal vascular anatomy in a 24-year-old man

    Science.gov (United States)

    Kavoussi, Shaheen C; Kempton, James E; Huang, John J

    2015-01-01

    An otherwise healthy 24-year-old man presented with a painless decrease of vision in the left eye for 2 days. Best-corrected visual acuity was 20/20 in the right eye and 20/80 in the left eye. Anterior exam was unremarkable and funduscopic exam in the left eye revealed retinal hemorrhages in all four quadrants with venous dilation and tortuosity consistent with central retinal vein occlusion. Fluorescein angiography revealed delayed venous filling with neither leakage nor vasculitis. A comprehensive work-up that included infectious, inflammatory, and hypercoagulability studies was unremarkable, and magnetic resonance imaging of the orbits was unrevealing. After 2 months, best-corrected visual acuity returned to 20/20-2 in the left eye. Upon closer review of the vascular anatomy in the left eye, a bifurcation of the central retinal artery at the level of the optic disc was tightly intertwined with an undilated nasal retinal vein in a manner that appeared to compress the underlying central retinal vein, resulting in dilation and tortuosity of the remaining venous branches. The vessel wall damage, turbulent venous flow, and compressive mass effect resulting from the anomalous retinal vasculature relationship is the proposed mechanism of the central retinal vein occlusion. Careful attention to the retinal vascular anatomy is suggested to aid in assessing the risk of retinal vein occlusion in any age group.

  1. 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.

  2. Diagnosis of Incidental Coronary-to-Bronchial Artery Fistula with CT Angiography: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Eun Ju; Lee, Ki Nam; Kim, Woo Jeong; Le, Jin Hwa; Oh, Jong Young [Dept. of Radiology, Dong A University Hospital, Dong A University College of Medicine, Pusan (Korea, Republic of)

    2012-04-15

    We report the case of a 64-year-old man with coronary-to-bronchial artery fistula (CBF) that was detected incidentally; the patient presented with the clinical manifestations of aortic dissection. Coronary CT angiography demonstrated tortuous vessels originating from the left circumflex coronary artery that were in communication with the bronchial arteries. CBF is a rare coronary artery anomaly and CBFs are asymptomatic in most cases. Familiarity with CT findings of CBF may help diagnose the incidental finding of CBF through the use of CT angiography undertaken for a different diagnostic purpose.

  3. A Biomechanical Model of Artery Buckling

    Science.gov (United States)

    Han, Hai-Chao

    2010-01-01

    The stability of arteries under blood pressure load is essential to the maintenance of normal arterial function and the loss of stability can lead to tortuosity and kinking that are associated with significant clinical complications. However, mechanical analysis of arterial bent buckling is lacking. To address this issue, this paper presents a biomechanical model of arterial buckling. Using a linear elastic cylindrical arterial model, the mechanical equations for arterial buckling were developed and the critical buckling pressure was found to be a function of the wall stiffness (Young’s modulus), arterial radius, length, wall thickness, and the axial strain. Both the model equations and experimental results demonstrated that the critical pressure is related to the axial strain. Arteries may buckle and become tortuous due to reduced (sub-physiological) axial strain, hypertensive pressure, and a weakened wall. These results are in accordance with, and provide a possible explanation to the clinical observations that these changes are the risk factors for arterial tortuosity and kinking. The current model is also applicable to veins and ureters. PMID:17689541

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

    Science.gov (United States)

    Hirahara, Shuichiro; Hirano, Yoshio; Yasukawa, Tsutomu; Ogura, Yuichiro

    2010-01-01

    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. PMID:20957057

  5. Electron beam CT diagnosis of coronary artery fistula: the clinical values

    International Nuclear Information System (INIS)

    Objective: To study the electron beam CT (EBCT) findings of coronary artery fistula. Methods: EBCT findings of 10 cases of coronary artery fistula proved by surgery were studied retrospectively. The series included 7 male and 3 female patients, aged from 2 to 55 years (48 years in average). Enhanced scan in single slice mode was performed. Results: EBCT revealed dilated and tortuous right coronary artery in 6 patients out of 7. Among those 6 patients a communication between the right coronary artery and the enlarged ventricular cavity was detected in 5 patients, while in the rest patient the proximal right coronary artery was connected with pulmonary trunk. EBCT revealed that coronary artery fistula was from the left coronary artery in 4 patients. In a case, the left dilated and calcified diagonal branch was communicated to the left ventricle. The left conical branch connected with pulmonary trunk in 2 cases. In another case the dilated and calcified major left coronary artery and its circumflex branch were revealed, and the latter went across the pre-left atrial space into the right atrium through the posterior wall. Conclusion: Coronary artery fistula is the first consideration when EBCT demonstrates an abnormal communication between the dilated and tortuous coronary artery or its branch and cardiac chamber or blood vessel

  6. Mechanical Buckling of Artery under Pulsatile Pressure

    Science.gov (United States)

    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 buckling pressure under pulsatile pressure both experimentally and theoretically, and to elucidate the relationship of critical pressures under pulsatile flow, steady flow, and static pressure. We first tested the buckling pressures of porcine carotid arteries under these loading conditions, and then proposed a nonlinear elastic artery model to examine the buckling pressures under pulsatile pressure conditions. Experimental results showed that under pulsatile pressure arteries buckled when the peak pressures were approximately equal to the critical buckling pressures under static pressure. This was also confirmed by model simulations at low pulse frequencies. Our results provide an effective tool to predict artery buckling pressure under pulsatile pressure. PMID:22356844

  7. Genetics Home Reference: Retinitis pigmentosa

    Science.gov (United States)

    ... PubMed Recent literature OMIM Genetic disorder catalog Conditions > Retinitis pigmentosa On this page: Description Genetic changes Inheritance ... names Glossary definitions Reviewed October 2010 What is retinitis pigmentosa? Retinitis pigmentosa is a group of related ...

  8. If I Had - Retinitis Pigmentosa

    Medline Plus

    Full Text Available ... Stem Cell Transplantation Shows Potential as Alternative MS Treatment VIDEO: If I Had - Retinitis Pigmentosa - Dr. Gerry ... D., whose research focuses on the cause, prevention, treatment, and cure of retinal disease, discuss retinitis pigmentosa. ...

  9. [Retinal manifestations of AIDS].

    Science.gov (United States)

    Cassoux, N; Reux, I; Guex-Crosier, Y; LeHoang, P

    1996-09-15

    Cytomegalovirus (CMV) retinitis is the most common retinal opportunistic infection in AIDS patients and is the main cause of blindness. It is generally associated with a CD4+ lymphocyte count below 50/microL. CMV retinitis is often asymptomatic (54% of the cases), frequent ophtalmoscopic screening is very important. Two virostatic drugs (Cymevan and Foscavir) have been approved for the treatment of CMV retinitis. Both are effective in preventing the progression of the lesion within 3 weeks of induction therapy. Long-term use of virostatic maintenance therapy delays the onset of relapses. The differential diagnosis of CMV retinitis are: human immunodeficiency virus retinopathy, varicella-zoster virus retinitis, ocular toxoplasmosis, syphilis, candida endophthalmitis in intravenous drug users, and unfrequently, tuberculosis, choroidal pneumocystosis, intraocular lymphoma. PMID:8949282

  10. 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.

  11. Retinal vascular tortuosity in obstructive sleep apnea

    Directory of Open Access Journals (Sweden)

    Mohsenin A

    2013-04-01

    Full Text Available Amir Mohsenin,1 Vahid Mohsenin,2 Ron A Adelman1 1Department of Ophthalmology and Visual Science, Yale University School of Medicine, New Haven, Connecticut, USA; 2Yale Center for Sleep Medicine, Department of Medicine, Yale University School of Medicine, New Haven, Connecticut, USA Purpose: Endothelial dysfunction and vascular disease are common in obstructive sleep apnea (OSA. We sought to examine the retinal vascular manifestations of OSA. Methods: Nine consecutive patients with OSA underwent ophthalmic examination regardless of any ocular complaints. Seven patients without OSA matched for demographics were used as controls. Fundus photographs from both eyes were used to quantitate retinal vascular tortuosity of the temporal arterial and venous arcades using ImageJ digital analysis software. The tortuosity of each vessel from the optic disc rim to the crossing point of a 5 disc diameter (5DD circle and 10 disc diameter (10DD circle centered on the optic disc were quantitated. Results: The mean age of patients with OSA in the study was 52 years ± SD of 10 years and 67 years ± SD of 10 years in the control group. The apnea-hypopnea index in patients with OSA ranged from 12 to 102 events/hr of sleep. The nadir oxyhemoglobin saturation during sleep in patients with OSA ranged from 60% to 87%. There was no significant difference in the frequency of diabetes or hypertension between the groups. Total tortuosity was increased at the 5DD (P = 0.011 and 10DD (P = 0.004 marks. Arterial tortuosity was significantly increased at the 10DD mark (P = 0.016. Venular tortuosity was increased at both the 5DD (P = 0.001 and 10DD (P = 0.028 marks. Conclusion: Patients with OSA have increased retinal vascular tortuosity as compared to matched controls. Increased tortuosity of the retinal vasculature may be a novel association with OSA. A larger prospective study will be necessary to further explore this relationship and its clinical significance. Keywords: retinal vessel tortuosity, sleep apnea, retinal vasculature, retinal vascular tortuosity

  12. Regulation of retinal oxygen metabolism in humans during graded hypoxia.

    Science.gov (United States)

    Palkovits, Stefan; Told, Reinhard; Schmidl, Doreen; Boltz, Agnes; Napora, Katarzyna J; Lasta, Michael; Kaya, Semira; Werkmeister, René M; Popa-Cherecheanu, Alina; Garhöfer, Gerhard; Schmetterer, Leopold

    2014-11-15

    Animal experiments indicate that the inner retina keeps its oxygen extraction constant despite systemic hypoxia. For the human retina no such data exist. In the present study we hypothesized that systemic hypoxia does not alter inner retinal oxygen extraction. To test this hypothesis we included 30 healthy male and female subjects aged between 18 and 35 years. All subjects were studied at baseline and during breathing 12% O? in 88% N? as well as breathing 15% O? in 85% N?. Oxygen saturation in a retinal artery (SO?art) and an adjacent retinal vein (SO?vein) were measured using spectroscopic fundus reflectometry. Measurements of retinal venous blood velocity using bidirectional laser Doppler velocimetry and retinal venous diameters using a Retinal Vessel Analyzer (RVA) were combined to calculate retinal blood flow. Oxygen and carbon dioxide partial pressure were measured from earlobe arterialized capillary blood. Retinal blood flow was increased by 43.0 ± 23.2% (P < 0.001) and 30.0 ± 20.9% (P < 0.001) during 12% and 15% O? breathing, respectively. SO?art as well as SO?vein decreased during both 12% O? breathing (SO?art: -11.2 ± 4.3%, P < 0.001; SO?vein: -3.9 ± 8.5%, P = 0.012) and 15% O? breathing (SO?art: -7.9 ± 3.6%, P < 0.001; SO?vein: -4.0 ± 7.0%, P = 0.010). The arteriovenous oxygen difference decreased during both breathing periods (12% O2: -28.9 ± 18.7%; 15% O?: -19.1 ± 16.7%, P < 0.001 each). Calculated oxygen extraction did, however, not change during our experiments (12% O?: -2.8 ± 18.9%, P = 0.65; 15% O?: 2.4 ± 15.8%, P = 0.26). Our results indicate that in healthy humans, oxygen extraction of the inner retina remains constant during systemic hypoxia. PMID:25217648

  13. Cytomegalovirus retinitis in AIDS.

    OpenAIRE

    Peters, M. J.; Moeller, H U; Russell-Eggitt, I; V. Novelli

    1995-01-01

    Cytomegalovirus retinitis is common in adults with AIDS but has been reported infrequently in children with perinatally acquired HIV infection. The cases are presented of two infants with vertically acquired HIV infection who developed disseminated cytomegalovirus infection and retinitis, and who posed difficult management issues.

  14. 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

  15. 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

  16. Thrombophilia and retinal vascular occlusion

    Directory of Open Access Journals (Sweden)

    Glueck CJ

    2012-08-01

    Full Text Available Charles J Glueck,1 Robert K Hutchins,2,3 Joel Jurantee,1 Zia Khan,1 Ping Wang11Cholesterol Center, Jewish Hospital of Cincinnati, Cincinnati, OH, USA; 2Department of Ophthalmology, University of Cincinnati College of Medicine, Cincinnati, OH, USA; 3Cincinnati Eye Institute, Cincinnati, OH, USAPurpose: The purpose of this research was to assess associations of thrombophilia with central retinal vein occlusion (CRVO, central retinal artery occlusion (CRAO, and amaurosis fugax (AF; to evaluate outcomes of normalizing high homocysteine; and to study CRVO, CRAO, and AF developing in estrogens/estrogen agonists in women subsequently shown to have thrombophilia.Methods: Measures of thrombophilia–hypofibrinolysis were obtained in 132 CRVO cases, 15 CRAO cases, and 17 AF cases. Cases were compared to 105 healthy control subjects who did not differ by race or sex and were free of any ophthalmologic disorders. All cardiovascular disease (CVD risk factors were compared to healthy general populations.Main outcome measures: The main outcome measure of this study was thrombophilia.Results: CRVO cases were more likely than controls to have high homocysteine (odds ratio [OR] 8.64, 95% confidence intervals [CI]: 1.96–38, high anticardiolipin immunoglobulin M (IgM; OR 6.26, 95% CI: 1.4–28.2, and high Factor VIII (OR 2.47, 95% CI: 1.31–7.9. CRAO-AF cases were more likely than controls to have high homocysteine (OR 14, 95% CI: 2.7–71.6 or the lupus anticoagulant (OR 4.1, 95% CI: 1.3–13.2. In four of 77 women with CRVO (two found to have high homocysteine, two with inherited high Factor XI, CRVO occurred after starting estrogen–progestins, estrogen–testosterone, or estrogen agonists. In one of eight women with CRAO found to have high anticardiolipin antibody IgG, CRAO occurred after starting conjugated estrogens, and AF occurred after starting conjugated estrogens in one of eleven women with AF (inherited protein S deficiency. Therapy for medians of 21 months (CRVO and 6 months (CRAO-AF was 5 mg folic acid, 100 mg B6, and 2000 mcg/day B12 normalized homocysteine in 13 of 16 (81% CRVO cases and all five CRAO-AF cases with pretreatment hyperhomocysteinemia. The CRVO cases had an excess of hypertension; CRAO-AF cases had an excess of type 2 diabetes and hypertension.Conclusion: Treatable thrombophilia, hyperhomocysteinemia in particular, is more common in RVO cases than in normal controls. RVO occurs after estrogens or estrogen agonists were administered in women subsequently shown to have thrombophilia.Keywords: central retinal vein occlusion, central retinal artery occlusion, amaurosis fugax, retinal vascular occlusion, thrombophilia, estrogen, estrogen agonist

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

    DEFF Research Database (Denmark)

    Willerslev, Anne; Li, Xiao Qiang

    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.

  18. 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)

  19. Retinal laser optical aids

    Directory of Open Access Journals (Sweden)

    Das Traprasad

    1991-01-01

    Full Text Available Knowledge of optics, comparative magnification and working field of view is essential for rational use of ophthalmoscopic contact lenses for retinal photocoagulation. The three commonly used contact lenses are described and compared.

  20. Retinal laser optical aids

    OpenAIRE

    Das Traprasad

    1991-01-01

    Knowledge of optics, comparative magnification and working field of view is essential for rational use of ophthalmoscopic contact lenses for retinal photocoagulation. The three commonly used contact lenses are described and compared.

  1. Intraocular retinal prosthesis.

    OpenAIRE

    Humayun, M S

    2001-01-01

    PURPOSE: An electronic implant that can bypass the damaged photoreceptors and electrically stimulate the remaining retinal neurons to restore useful vision has been proposed. A number of key questions remain to make this approach feasible. The goal of this thesis is to address the following 2 specific null hypotheses: (1) Stimulus parameters make no difference in the electrically elicited retinal responses. (2) Just as we have millions of photoreceptors, so it will take a device that can gene...

  2. Retinal Detachment in Preeclampsia

    OpenAIRE

    Prado Renata Silva do; Figueiredo Estêvão Lanna; Magalhães Télcia Vasconcelos Barros

    2002-01-01

    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 unnecessar...

  3. Retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    Hayreh Sohan

    1994-01-01

    Full Text Available In this review of the retinal vein occlusion (RVO, I have summarized recent advances on several controversial and clinically important topics: classification of RVO into six distinct clinical entities; pathogeneses and demographic characteristics of various types of RVO; differentiation of non-ischemic from ischemic central retinal vein occlusion (CRVO; differentiation of hemi-CRVO (HCRVO from major branch RVO (BRVO; and the course, complications and management of various types of RVO

  4. Acute retinal necrosis.

    Science.gov (United States)

    Bonfioli, Adriana A; Eller, Andrew W

    2005-01-01

    Acute retinal necrosis (ARN) is an uncommon intraocular inflammatory syndrome characterized by severe and diffuse uveitis, retinal vasculitis, and retinal necrosis. It is typically described to occur in immunocompetent patients, but can also be found in immunocompromised subjects. Varicella-zoster virus (VZV), herpes simplex virus (HSV 1 and 2), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) have been implicated in the etiology of ARN. The characteristic features of the disease include iridocyclitis, vitritis, retinal vasculitis, and retinal necrosis. Bilateral involvement occurs in two-thirds of the patients, frequently in the first six weeks, but sometimes months to years later. Retinal detachment occurs in 75% of the cases. The diagnosis of ARN is usually based in clinical features. The use of polymerase chain reaction (PCR) in aqueous humor samples is useful to identify the etiology of the disease. The treatment of ARN includes intravenous acyclovir, corticosteroids and aspirin. To prevent fellow eye involvement, intravenous acyclovir is followed by oral acyclovir for 14 weeks. Alternatives to acyclovir include ganciclovir, foscarnet, famcyclovir, brivudine, and valgancyclovir. PMID:16282149

  5. Hypoxia-ischemia and retinal ganglion cell damage

    Directory of Open Access Journals (Sweden)

    Charanjit Kaur

    2008-08-01

    Full Text Available Charanjit Kaur1, Wallace S Foulds2, Eng-Ang Ling11Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; 2Singapore Eye Research Institute, SingaporeAbstract: Retinal hypoxia is the potentially blinding mechanism underlying a number of sight-threatening disorders including central retinal artery occlusion, ischemic central retinal vein thrombosis, complications of diabetic eye disease and some types of glaucoma. Hypoxia is implicated in loss of retinal ganglion cells (RGCs occurring in such conditions. RGC death occurs by apoptosis or necrosis. Hypoxia-ischemia induces the expression of hypoxia inducible factor-1? and its target genes such as vascular endothelial growth factor (VEGF and nitric oxide synthase (NOS. Increased production of VEGF results in disruption of the blood retinal barrier leading to retinal edema. Enhanced expression of NOS results in increased production of nitric oxide which may be toxic to the cells resulting in their death. Excess glutamate release in hypoxic-ischemic conditions causes excitotoxic damage to the RGCs through activation of ionotropic and metabotropic glutamate receptors. Activation of glutamate receptors is thought to initiate damage in the retina by a cascade of biochemical effects such as neuronal NOS activation and increase in intracellular Ca2+ which has been described as a major contributing factor to RGC loss. Excess production of proinflammatory cytokines also mediates cell damage. Besides the above, free-radicals generated in hypoxic-ischemic conditions result in RGC loss because of an imbalance between antioxidant- and oxidant-generating systems. Although many advances have been made in understanding the mediators and mechanisms of injury, strategies to improve the damage are lacking. Measures to prevent neuronal injury have to be developed.Keywords: retinal hypoxia, retinal ganglion cells, glutamate receptors, neuronal injury, retina

  6. 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...

  7. Photovoltaic retinal prosthesis

    Science.gov (United States)

    Loudin, James; Mathieson, Keith; Kamins, Ted; Wang, Lele; Galambos, Ludwig; Huie, Philip; Sher, Alexander; Harris, James; Palanker, Daniel

    2011-03-01

    Electronic retinal prostheses seek to restore sight to patients suffering from retinal degenerative disorders. Implanted electrode arrays apply patterned electrical stimulation to surviving retinal neurons, producing visual sensations. All current designs employ inductively coupled coils to transmit power and/or data to the implant. We present here the design and initial testing of a photovoltaic retinal prosthesis fabricated with a pixel density of up to 177 pixels/mm2. Photodiodes within each pixel of the subretinal array directly convert light to stimulation current, avoiding the use of bulky coil implants, decoding electronics, and wiring, and thereby reducing surgical complexity. A goggles-mounted camera captures the visual scene and transmits the data stream to a pocket processor. The resulting images are projected into the eyes by video goggles using pulsed, near infrared (~900 nm) light. Prostheses with three pixel densities (15, 55, and 177 pix/mm2) are being fabricated, and tests indicate a charge injection limit of 1.62 mC/cm2 at 25Hz. In vitro tests of the photovoltaic retinal stimulation using a 512-element microelectrode array have recorded stimulated spikes from the ganglion cells, with latencies in the 1-100ms range, and with peak irradiance stimulation thresholds varying from 0.1 to 1 mW/mm2. With 1ms pulses at 25Hz the average irradiance is more than 100 times below the IR retinal safety limit. Elicited retinal response disappeared upon the addition of synaptic blockers, indicating that the inner retina is stimulated rather than the ganglion cells directly, and raising hopes that the prosthesis will preserve some of the retina's natural signal processing.

  8. If I Had - Retinitis Pigmentosa

    Science.gov (United States)

    ... as Alternative MS Treatment VIDEO: If I Had - Retinitis Pigmentosa - Dr. Gerry Chader, MD, PhD, University of ... Back to Home Page VIDEO: If I Had - Retinitis Pigmentosa - Dr. Gerry Chader, MD, PhD, University of ...

  9. If I Had - Retinitis Pigmentosa

    Medline Plus

    Full Text Available ... Ph.D., whose research focuses on the cause, prevention, treatment, and cure of retinal disease, discuss retinitis ... Medicine. Dr. Charder’s research focuses on the cause, prevention, and treatment, as well as the cure of ...

  10. 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.

  11. 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.

  12. Finding the retinal break in rhegmatogenous retinal detachment

    Directory of Open Access Journals (Sweden)

    Saxena Sandeep

    2001-01-01

    Full Text Available The development of subretinal fluid is governed by a limited number of anatomical factors and gravity. As a result, rhegmatogenous retinal detachments form in a predictable manner around the retinal break of their origin. The shape of the detachments points to the position of the break. The purpose of this review is to describe the characterstic contours of subretinal fluid in rhegmatogenous retinal detachments, and to highlight some rules and methodology which can help in the detection of the retinal break in phakic, psuedophakic and recurrent retinal detachments.

  13. Retinal vascular calibres are significantly associated with cardiovascular risk factors : the Tromsø Eye Study

    DEFF Research Database (Denmark)

    von Hanno, T.; Bertelsen, G.

    2014-01-01

    Purpose: To describe the association between retinal vascular calibres and cardiovascular risk factors. Methods: Population-based cross-sectional study including 6353 participants of the TromsO Eye Study in Norway aged 38-87years. Retinal arteriolar calibre (central retinal artery equivalent) and retinal venular calibre (central retinal vein equivalent) were measured computer-assisted on retinal photographs. Data on blood pressure, body mass index (BMI), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, glycosylated haemoglobin (HbA1c) and smoking were collected. Association between retinal vessel calibre and the cardiovascular risk factors was assessed by multivariable linear and logistic regression analyses. Results: Retinal arteriolar calibre was independently associated with age, blood pressure, HbA1c and smoking in women and men, and with HDL cholesterol in men only. Blood pressure had the strongest effect on arteriolar calibre, with a decrease in calibre of 3.6m (women)/4.1m (men) per standard deviation increase in mean arterial blood pressure. Retinal venular calibre was independently associated with age, blood pressure, BMI, HDL and LDL cholesterol and smoking in men and women. The effect of BMI and HDL cholesterol on venular calibre was significantly stronger in men than in women. Current smoking was the most important factor for venular calibre, where smokers had 13.2m (women)/15.2m (men) wider calibre than nonsmokers. Conclusion: All the explored cardiovascular risk factors were independently associated with retinal vascular calibre, with stronger effect of HDL cholesterol and BMI in men than in women. Blood pressure and smoking contributed most to the explained variance.

  14. Retinal Detachment in Preeclampsia

    Directory of Open Access Journals (Sweden)

    Renata Silva do Prado

    2002-08-01

    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.

  15. Clinical and immunological features of retinal vasculitis in systemic diseases

    Directory of Open Access Journals (Sweden)

    Paovi? Jelena

    2009-01-01

    Full Text Available Background/Aim. Vasculitis is a clinical, pathologic process characterized by inflammation and necrosis of blood vessel occurring anywhere in the body. The aim of the study was to present some clinical and immunologic features of retinal vasculitis in systemic diseases: systemic lupus erythematosus, multiple sclerosis, sarcoidosis, Behcet's diseases, and others. Methods. A total of 1 254 patients with uveitis were included in the study. The immunochemical diagnostic methods were used to determine the pathogenesis of ocular manifestations. Ocular manifestations were examined using biomicroscope, direct or indirect ophtalmoscopy. Results. Primary retinal vasculitis was diagnosed in 85/1254 (6.8% of total uveitis. In more than half of the cases of vasculitis (58.8%, both arteries and veins were involved in inflammatory process. Periphlebitis was diagnosed far more commonly (36.5% than periarteritis (4.7%. Retinal vasculitis associated with systemic lupus erythematosus was characterized by microinfarctions and the consequent foci of inflammatory cells or diseases of large arteries manifesting in vasospasm and occlusions. Cotton wool spots occurred in 38.3% and retinal hemorrhages in 34% of the cases. In this study periphlebitis of the retina was one of the less frequent ocular manifestations of multiple sclerosis. Comparing with the other changes of the retinal blood vessels, venous sheating occurred in 25.1% and occlusion and vein trombosis in 43.75% of the cases. Retinal vasculitis associated with chronic sarcoidosis occured in 37.5% of patients with sarcoidosis. The most frequent manifestation of ocular sarcoidosis was intermediary uveitis (43.75%. Anterior granulomatous uveitis occured in 37.5% of patients with sarcoidoses. Immune complexes occurred in 13/20 (65% of the patients. Antiretinal anti-S antibody in the serum occurred in 73% of the patients with retinal detachment as a complication of primary disease and in 25% those with vasculitis. Conclusion. Systemic diseases such as Behcet's syndrome, collagen vascular diseases, systemic granulomatous diseases (sarcoidosis and tuberculosis were the main causes of retinal vasculitis. Knowledge of the symptomatology and pathogenesis of retinal vasculitis is of the major significance for the diagnosis and therapy of the disease.

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

    DEFF Research Database (Denmark)

    Willerslev, Anne; Li, Xiao Q

    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 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 bifurcations. In contrast, the blood stream at the site of confluence of two retinal veins remains divided into two parallel sets of sheets with separate velocity distribution for a downstream distance of at least four trunk vessel diameters. Consequently, retinal trunk vessels near bifurcations/confluences have distinctly different internal SD-OCT profiles, a figure-of-8 pattern in arteries and a figure figure-of-88 in veinsthat can be used to distinguish between the two vessel types. CONCLUSION: This study verified the hypothesis that directions of blood flow at dichotomous vascular branchings can be 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.

  17. Reflectance pulse oximetry measurements from the retinal fundus.

    OpenAIRE

    de Kock, JP; Tarassenko, L; Glynn, CJ; Hill, AR

    1993-01-01

    Conventional transmission pulse oximetry is a noninvasive technique for the continuous monitoring of arterial oxygen saturation (SaO2) from peripheral vascular beds such as the finger tip or earlobe. In this paper we propose to exploit the unique transparency of the ocular media to make reflectance pulse oximetry measurements on the retinal fundus. This technique potentially offers significant advantages over conventional pulse oximetry, primarily the ability to monitor cerebral, as opposed t...

  18. Retinal circulation during a spontaneous rise of intraocular pressure.

    OpenAIRE

    Grunwald, J E; Riva, C E; Kozart, D M

    1988-01-01

    The retinal haemodynamic changes occurring in an eye with a spontaneous elevation of intraocular pressure were investigated by bidirectional laser Doppler velocimetry and monochromatic fundus photography. At an intraocular pressure of 47 mmHg the blood velocity and volumetric blood flow rate were significantly smaller and arterial blood velocity pulsatility was significantly greater than normal. The corresponding 88% reduction in perfusion pressure was accompanied by a 67% reduction in total ...

  19. Measurement of oxygen saturation in small retinal vessels with adaptive optics confocal scanning laser ophthalmoscope

    Science.gov (United States)

    Li, Hao; Lu, Jing; Shi, Guohua; Zhang, Yudong

    2011-11-01

    We have used an adaptive optics confocal scanning laser ophthalmoscope to assess oxygen saturation in small retinal vessels. Images of the vessels with a diameter smaller than 50 ?m are recorded at oxygen sensitive and isosbestic wavelengths (680 and 796 nm, respectively). The vessel optical densities (ODs) are determined by a computer algorithm. Then, OD ratios (ODRs), which are inversely proportional to oxygen saturation, are calculated. The results show that arterial ODRs are significantly smaller than venous ODRs, indicating that oxygen saturation in the artery is higher than that in the vein. To the best of our knowledge, this is the first noninvasive measurement of oxygen saturation in small retinal vessels.

  20. 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.

  1. Ovarian Artery: Angiographic Appearance, Embolization and Relevance to Uterine Fibroid Embolization

    International Nuclear Information System (INIS)

    Purpose: To describe the angiographic appearance of the ovarian artery and its main variations that may be relevant to uterine fibroid embolization. Methods: The flush aortograms of 294 women who had been treated by uterine artery embolization for fibroids were reviewed. Significant arterial supply to the fibroid, and the origin and diameter of identified ovarian arteries were recorded. In patients with additional embolization of the ovarian artery, the follow-up evaluation also included hormonal levels and Doppler imaging of the ovaries. Results: A total of 75 ovarian arteries were identified in 59 women (bilaterally in 16 women and unilaterally in 43 women). All ovarian arteries originated from the aorta below the level of the renal arteries with a characteristic tortuous course. Fifteen women had at least one enlarged ovarian artery supplying the fibroids. Fourteen women (14/15, 93%) presented at least one of the following factors: prior pelvic surgery, tubo-ovarian pathology or large fundal fibroids. Conclusion: We advocate the use of flush aortography in women with prior tubo-ovarian pathology or surgery or in cases of large fundal fibroids. In the case of an ovarian artery supply to the fibroids, superselective catheterization and embolization of the ovarian artery should be considered

  2. An in vivo rat model of artery buckling for studying wall remodeling.

    Science.gov (United States)

    Zhang, Jinzhou; Liu, Qin; Han, Hai-Chao

    2014-08-01

    Theoretical modeling and in vitro experiments have demonstrated that arterial buckling is a possible mechanism for the development of artery tortuosity. However, there has been no report of whether artery buckling develops into tortuosity, partially due to the lack of in vivo models for long-term studies. The objective of this study was to establish an in vivo buckling model in rat carotid arteries for studying arterial wall remodeling after buckling. Rat left carotid arteries were transplanted to the right carotid arteries to generate buckling under in vivo pressure and were maintained for 1 week to examine wall remodeling and adaptation. Our results showed that a significant buckling was achieved in the carotid arterial grafts with altered wall stress. Cell proliferation and matrix metalloprotinease-2 (MMP-2) expression in the buckled arteries increased significantly compared with the controls. The tortuosity level of the grafts also slightly increased 1 week post-surgery, while there was no change in vessel dimensions, blood pressure, and blood flow velocity. The artery buckling model provides a useful tool for further study of the adaptation of arteries into tortuous shapes. PMID:24793586

  3. Influence of Latanoprost on Retinal Microcirculation in Glaucoma

    Science.gov (United States)

    Kremmer, S; Iliadou, M; Anastassiou, G; Schallenberg, M; Vilser, W; Steuhl, K.P; Selbach, J.M

    2014-01-01

    Purpose : To test whether latanoprost has an influence on ocular haemodynamics, considering the general reputation of prostaglandins which is frequently associated with vasoconstriction. The effect of latanoprost on the retinal blood supply of treatment-naïve glaucoma patients was tested. Materials and Methodology : 13 patients (7 male, 6 female) who had just recently been diagnosed with primary open-angle glaucoma (POAG) were treated with latanoprost (0.005%). The average age of our study group was 63.8 years (+/- 2.9 years). The drug’s effect on retinal autoregulation was assessed by flicker test using the Dynamic Vessel Analyzer (DVA). Examinations took place before initializing treatment, after 4 weeks and once again after 4 to 6 months. Results : In our group of POAG patients, the IOP under treatment was significantly reduced about 25%. No intraindividual differences in systemic blood pressure and heart rate were observed. In DVA measurements of glaucoma patients, the maximum flicker dilation of the arteries was significantly lower than reported for healthy volunteers. Beyond that, POAG patients did not show significant differences in vessel diameters, peak amplitudes as well as maximum dilations of retinal arteries and veins before and under treatment with latanoprost (0.005%). Conclusion : Latanoprost markedly lowered the IOP but it did not exert a significant effect on retinal haemodynamics. There was neither a tendency towards vasoconstriction nor towards vasodilation. Sustaining reperfusion damage after topical latanoprost therapy thus seems to be highly unlikely. Further studies must show if sole IOP lowering or a dual positive effect – IOP lowering and improvement of retinal vessel autoregulation – have a more positive impact on the long term follow-up of glaucoma patients. PMID:25317217

  4. Contrast sensitivity in retinitis pigmentosa.

    OpenAIRE

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

  5. Retinal detachment following excimer laser

    OpenAIRE

    Charteris, D.; Cooling, R.; Lavin, M.; Mcleod, D.

    1997-01-01

    AIMS—To report the clinical presentation, surgical management, and outcome of retinal detachment following excimer laser.?METHODS—Retrospective analysis of retinal detachments observed in 11 eyes of 10 myopic patients who had previously undergone photorefractive keratectomy (PRK) or phototherapeutic keratectomy (PTK) by excimer laser.?RESULTS—Symptoms of visual loss in two eyes were initially attributed to corneal haze. In 10 of 11 eyes visualisation of the retinal detachment an...

  6. 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.

  7. 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.

  8. Oxygen saturation measurements of blood in retinal vessels during blood loss

    Science.gov (United States)

    Smith, Matthew H.; Denninghoff, Kurt R.; Hillman, Lloyd W.; Chipman, Russell A.

    1998-07-01

    We describe a noninvasive technique and instrumentation for measuring the oxygen saturation of blood in retinal arteries and veins. The measurements are made by shining low-power lasers into the eye, and scanning the beams across a retinal blood vessel. The light reflected and scattered back out of the eye is collected and measured. The oxygen saturation of blood within the vessel is determined by analyzing the vessel absorption profiles at two wavelengths. A complete saturation measurement can be made in less than 1 s, allowing real-time measurement during physiologic changes. The sensitivity of this measurement technique to changes in retinal saturation has been demonstrated through a series of pilot studies in anesthetized swine. We present data indicating that retinal venous oxygen saturation decreases during ongoing blood loss, demonstrating a potential application of an eye oximeter to noninvasively monitor blood loss.

  9. Oclusão de ramo da veia central da retina Retinal vein branch occlusion

    Directory of Open Access Journals (Sweden)

    Alexandre Antonio Marques Rosa

    2003-12-01

    Full Text Available As oclusões venosas retinianas são a segunda causa mais comum de doenças vasculares da retina, atrás apenas da retinopatia diabética. A obstrução venosa de ramo é definida como a oclusão focal de uma veia retiniana em nível de um cruzamento arteriovenoso, no qual a artéria passa anteriormente à veia. Serão revisto o estudo multicêntrico sobre o tratamento com fotocoagulação a "laser" para esta doença, bem como abordadas as novas terapêuticas cirúrgicas propostas.Retinal venous occlusions are the second most common retinal vascular diseases, behind diabetic retinopathy. The retinal vein branch occlusion is defined as a retinal vein focal occlusion at the level of an arteriovenous crossing, where the artery lies anterior to vein. The clinical trial with laser photocoagulation for this disease, as well as new proposed surgical therapeutic techniques will be reviewed.

  10. Oclusão de ramo da veia central da retina / Retinal vein branch occlusion

    Scientific Electronic Library Online (English)

    Alexandre Antonio Marques, Rosa.

    2003-12-01

    Full Text Available As oclusões venosas retinianas são a segunda causa mais comum de doenças vasculares da retina, atrás apenas da retinopatia diabética. A obstrução venosa de ramo é definida como a oclusão focal de uma veia retiniana em nível de um cruzamento arteriovenoso, no qual a artéria passa anteriormente à veia [...] . Serão revisto o estudo multicêntrico sobre o tratamento com fotocoagulação a "laser" para esta doença, bem como abordadas as novas terapêuticas cirúrgicas propostas. Abstract in english Retinal venous occlusions are the second most common retinal vascular diseases, behind diabetic retinopathy. The retinal vein branch occlusion is defined as a retinal vein focal occlusion at the level of an arteriovenous crossing, where the artery lies anterior to vein. The clinical trial with laser [...] photocoagulation for this disease, as well as new proposed surgical therapeutic techniques will be reviewed.

  11. 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.

  12. Comorbidity in patients with branch retinal vein occlusion : case-control study

    DEFF Research Database (Denmark)

    Bertelsen, Mette; Linneberg, Allan

    2012-01-01

    To evaluate comorbidity before and after the diagnosis of branch retinal vein occlusion to determine whether it is a consequence of arterial thickening and therefore could serve as a diagnostic marker for other comorbidities and to evaluate the risk factors for the development of such occlusion.

  13. Comorbidity in patients with branch retinal vein occlusion: case-control study

    OpenAIRE

    Bertelsen, Mette; Linneberg, Allan; Rosenberg, Thomas; Christoffersen, Nynne; Vorum, Henrik; Gade, Else; Larsen, Michael

    2012-01-01

    Objectives To evaluate comorbidity before and after the diagnosis of branch retinal vein occlusion to determine whether it is a consequence of arterial thickening and therefore could serve as a diagnostic marker for other comorbidities and to evaluate the risk factors for the development of such occlusion.

  14. Trombocitemia esencial y trombosis venosa retiniana / Essential thrombocythemia and retinal vein thrombosis

    Scientific Electronic Library Online (English)

    VM, Asensio Sánchez; G, Manteca Jiménez; E, Cano Navarro.

    2004-12-01

    Full Text Available Casos Clínicos: La trombocitosis esencial es una enfermedad de las células madres hematopoyéticas que se caracteriza por un exceso de plaquetas. Se presentan dos casos, una mujer de 72 años con retina isquémica, venas tortuosas y convertidas en cordones blanquecinos en la retina superior y hemorragi [...] as difusas en la retina inferior con hemorragias puntiformes en la región ecuatorial en el ojo izquierdo y un varón de 62 años con oclusión de la vena central de la retina en el ojo izquierdo, como manifestaciones de trombocitemia esencial. Discusión: Estos casos clínicos son ejemplos de las posibles complicaciones de la trombocitosis esencial. Estos pacientes deberían ser controlados ante posibles complicaciones oclusivas retinianas, especialmente al reducir el recuento plaquetario por debajo de 10(6)/mm³. Abstract in english Case Report: Essential thrombocytosis is a disorder of the hematopoietic stem cell that causes proliferation of platelets. We report two cases: a 72-year-old woman with ischemic retina and tortuous and white veins in the superior retina and diffuse hemorrhages in the inferior retina with blot hemorr [...] hages scattered throughout the equatorial region in the left eye; and a 62-year-old man with a central retinal vein occlusion in the left eye as signs of essential thrombocythemia. Discusion: These cases are examples of potential complications of essential thrombocytosis. Vulnerable patients should be monitored for retinal vascular occlusions, especially when platelet counts do not exceed 106/mm³.

  15. Trombocitemia esencial y trombosis venosa retiniana Essential thrombocythemia and retinal vein thrombosis

    Directory of Open Access Journals (Sweden)

    VM Asensio Sánchez

    2004-12-01

    Full Text Available Casos Clínicos: La trombocitosis esencial es una enfermedad de las células madres hematopoyéticas que se caracteriza por un exceso de plaquetas. Se presentan dos casos, una mujer de 72 años con retina isquémica, venas tortuosas y convertidas en cordones blanquecinos en la retina superior y hemorragias difusas en la retina inferior con hemorragias puntiformes en la región ecuatorial en el ojo izquierdo y un varón de 62 años con oclusión de la vena central de la retina en el ojo izquierdo, como manifestaciones de trombocitemia esencial. Discusión: Estos casos clínicos son ejemplos de las posibles complicaciones de la trombocitosis esencial. Estos pacientes deberían ser controlados ante posibles complicaciones oclusivas retinianas, especialmente al reducir el recuento plaquetario por debajo de 10(6/mm³.Case Report: Essential thrombocytosis is a disorder of the hematopoietic stem cell that causes proliferation of platelets. We report two cases: a 72-year-old woman with ischemic retina and tortuous and white veins in the superior retina and diffuse hemorrhages in the inferior retina with blot hemorrhages scattered throughout the equatorial region in the left eye; and a 62-year-old man with a central retinal vein occlusion in the left eye as signs of essential thrombocythemia. Discusion: These cases are examples of potential complications of essential thrombocytosis. Vulnerable patients should be monitored for retinal vascular occlusions, especially when platelet counts do not exceed 106/mm³.

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

    OpenAIRE

    M. Grossherr; 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...

  17. 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.

  18. Acute hyperinsulinemia increases the contraction of retinal arterioles induced by elevated blood pressure

    DEFF Research Database (Denmark)

    Jeppesen, Peter; Knudsen, SØren Tang

    2013-01-01

    Diabetic retinopathy is accompanied by disturbances in retinal blood flow, which is assumed to be related to the diabetic metabolic dysregulation. It has previously been shown that normoinsulinemic hyperglycemia has no effect on the diameter of retinal arterioles at rest and during an increase in the arterial blood pressure induced by isometric exercise. However, the influence of hyperinsulinemia on this response has not been studied in detail. In seven normal persons, the diameter response of retinal arterioles to an increased blood pressure induced by isometric exercise, to stimulation with flickering light, and to the combination of these stimuli was studied during euglycemic normoinsulinemia (protocol N) on one examination day, and euglycemic hyperinsulinemia (protocol H) on another examination day. Isometric exercise induced significant contraction of retinal arterioles at all examinations, but during a repeated examination the diameter response was significantly reduced in the test persons following theN protocol and increased in the persons following the H protocol. Flicker stimulation induced a significant dilatation of retinal arterioles at all examinations, and the response was significantly higher during a repeated examination, irrespective of the insulin level. Repeated exposure to isometric exercise reduces contraction, whereas repeated exposure to flickering light increases dilatation of retinal arterioles in vivo. Hyperinsulinemia increases contraction of retinal arterioles induced by isometric exercise.

  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. 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.

  1. 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.

  2. If I Had - Retinitis Pigmentosa

    Medline Plus

    Full Text Available ... as Alternative MS Treatment VIDEO: If I Had - Retinitis Pigmentosa - Dr. Gerry Chader, MD, PhD, University of ... Back to Home Page VIDEO: If I Had - Retinitis Pigmentosa - Dr. Gerry Chader, MD, PhD, University of ...

  3. Perceptual Fading without Retinal Adaptation

    Science.gov (United States)

    Hsieh, Po-Jang; Colas, Jaron T.

    2012-01-01

    A retinally stabilized object readily undergoes perceptual fading and disappears from consciousness. This startling phenomenon is commonly believed to arise from local bottom-up sensory adaptation to edge information that occurs early in the visual pathway, such as in the lateral geniculate nucleus of the thalamus or retinal ganglion cells. Here…

  4. 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

  5. Pathogenesis and Risk Factors In Retinal Vein Occlusions

    Directory of Open Access Journals (Sweden)

    Koray Gümü?

    2007-08-01

    Full Text Available Retinal vein occlusions (RVO are by far the most common cause of retinal vascular occlusive diseases especially in middle-aged and older individuals. Basically, there are two forms of RVO, namely, branch retinal vein occlusion (BRVO and central retinal vein occlusion (CRVO. Even though mechanisms resulting in venous occlusion may differ, there are also similarities in the etiopathogenesis of these two types. Like other vascular occlusive diseases elsewhere in the body, it is very crucial to find out if there is an underlying cause and / or predisposing factor for RVO. Most researches show that the pathogenesis of RVO is multifactorial and the most common associated disease is arterial hypertension. Moreover, recent investigations have determined that numerous genetic and acquired disorders may predispose to RVO and thereby affect visual prognosis. In this review, it was aimed to consider the pathogenesis of RVO along with its local, systemic and haemostasis-related risk factors and to discuss well-known as well as new predisposing factors for thrombosis.

  6. Retinal Doppler Ultrasound and Homocystein Levels in Children with Type I Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    Tolga Altu? ?en

    2008-06-01

    Full Text Available Aim: We aimed to measure plasma homocysteine levels and retinal arterial blood flow of type 1 diabetic children by Doppler ultrasound, which were known to be related with diabetic retinopathy and to compare them with healthy children. Materials and Methods: We selected 42 diabetic children (22 females, 20 males, between the ages of 8 to18 years (mean 13,2±4,3. Mean duration of type 1 diabetes was 5,02±2,99 years. For the control group, 30 children (15 females, 15 males between the ages of 9 to 18 years (mean 14,01±3,5 were selected. In central retinal arteries and ophthalmic arteries, peak systolic velocity, diastolic velocity, pulsatility and resistivity indexes were measured. Results: Except for the higher central retinal artery diastolic velocity in the control group, retinal blood flow velocities were similiar in diabetic children and the control group (p0,05. Mean ophthalmic artery peak systolic velocity (37,33±12,79 cm/sec for well controlled diabetic children was higher than the poorly controlled group (31,1±17,17 cm/sec; mean ophthalmic artery resistivity index (0,76±0,08 for well controlled group was lower than the mean resistivity index (0,82±0,04 of poorly controlled group. Plasma homocysteine levels were higher in diabetic children (10,3±2,18 mmol/L than the control group (9,12±1,9 mmol/L (p<0,05. Plasma homocysteine levels of the poorly controlled diabetics (9,42±2,12 mmol/L were higher than the well controlled diabetics (11,33±2,05 mmol/L.Conclusion: In the poorly controlled group total plasma homocysteine levels and ophthalmic artery resistivity indexes were increased compared to the well controlled diabetics and healthy children which might be risk factors for diabetic retinopathy. (Journal of Current Pediatrics 2008; 6: 19-25

  7. 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.

  8. Selective inner retinal layer involvement in early syphilitic retinitis as evidenced by spectral domain OCT

    OpenAIRE

    Klemencic, Stephanie A.; Newman, Tricia L.; Messner, Leonard V.

    2011-01-01

    Retinitis as a feature of syphilitic uveitis in immunocompromised individuals is a common finding. We present spectral domain OCT images of early syphilitic retinitis pre and post treatment with penicillin. This case suggests that the inner retinal layers may be selectively involved with early syphilitic retinitis. Early treatment is important to avoid outer layer retinal involvement and to decrease ocular morbidity.

  9. 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.

  10. Acute arterial occlusion - kidney

    Science.gov (United States)

    ... arterial thrombosis; Renal artery embolism; Acute renal artery occlusion; Embolism - renal artery ... often result in permanent kidney failure. Acute arterial occlusion of the renal artery can occur after injury ...

  11. Multispectral confocal scanning laser ophthalmoscope for retinal vessel oximetry

    Science.gov (United States)

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

    2000-03-01

    Scanning laser microscopy is a widely used technique in ophthalmoscopy for providing high-resolution real time images of the retina. We describe a scanning laser ophthalmoscope that acquires retinal images at four wavelengths for the purpose of measuring the oxygen saturation of blood in retinal arteries and veins. Images at all four wavelengths are obtained across a single video frame using a temporal interlacing technique. An extraction procedure then permits analysis of four monochromatic images. A technique for calculating oxygen saturation from a multi-spectral image set is presented, along with preliminary measurements. The choice of wavelengths dramatically affects the oxygen saturation calculation accuracy and we present an optimized wavelength set and the calculated oxygen saturation results. The potential applications for this technology range from the diagnosis of various ophthalmic diseases to the detection of blood loss in trauma victims.

  12. Retinal hemorrhage as a unique ophthalmic manifestation of cerebral hyper perfusion syndrome

    Directory of Open Access Journals (Sweden)

    Eitan Heldenberg

    2013-06-01

    Full Text Available Cerebral hyperperfusion syndrome (CHPS is a rare disease with complications of carotid artery revascularization. Acute retinal hemorrhage is a very rare entity that has been previously described as a manifestation of CHPS followed by the carotid artery stenting (CAS, but to the best of our knowledge, not yet described as a complication of carotid surgery. An Ascending Aorta to bilateral Carotid bypass was performed in a 35 years old woman with active Takayasu arteritis and 95% symptomatic stenosis of both common carotid arteries. Severe retinal hemorrhage appeared on the second post operative day combined with high blood pressure, brain edema on CT scan and grand mal seizures. It seems that fundoscopic examination followed by the carotid revascularization of tightness can be helpful in identifying those patients who develop symptoms suggesting of CHPS.

  13. Retinal hemorrhage as a unique ophthalmic manifestation of cerebral hyper perfusion syndrome

    Directory of Open Access Journals (Sweden)

    Eitan Heldenberg

    2013-07-01

    Full Text Available Cerebral hyperperfusion syndrome (CHPS is a rare, complication of carotid artery revascularization. Acute retinal hemorrhage is a very rare entity previously described as a manifestation of CHPS following carotid artery stenting (CAS, but to the best of our knowledge, not yet described as a complication of carotid surgery. An Ascending Aorta to bilateral Carotid bypass was performed in a 35-year-old woman with active Takayasu arteritis and 95% symptomatic stenosis of both common carotid arteries. Severe retinal hemorrhage appeared on the second post operative day combined with high blood pressure, brain edema on CT scan and grand mal seizures. It seems that fundoscopic examination following carotid revascularization of tight can be helpful in identifying those patients who develop symptoms suggesting of CHPS.

  14. 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.

  15. 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.

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

    Directory of Open Access Journals (Sweden)

    I. Demirkan

    2012-05-01

    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.

  17. 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).

  18. 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; 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

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

    Science.gov (United States)

    2011-01-01

    Purpose. When a patient suffers a retinal detachment and surgery is delayed, it is known clinically that bilaterally patching the patient may allow the retina to partially reattach or “settle.” Although this procedure has been performed since the 1860s, there is still debate as to how such a maneuver facilitates the reattachment of the retina. Methods. Finite element calculations using commercially available analysis software are used to elucidate the influence of reduction in eye movement caused by bilateral patching on the flow of subretinal fluid in a physical model of retinal detachment. Results. It was found that by coupling fluid mechanics with structural mechanics, a physically consistent explanation of increased retinal detachment with eye movements can be found in the case of traction on the retinal hole. Large eye movements increase vitreous traction and detachment forces on the edge of the retinal hole, creating a subretinal vacuum and facilitating increased subretinal fluid. Alternative models, in which intraocular fluid flow is redirected into the subretinal space, are not consistent with these simulations. Conclusions. The results of these simulations explain the physical principles behind bilateral patching and provide insight that can be used clinically. In particular, as is known clinically, bilateral patching may facilitate a decrease in the height of a retinal detachment. The results described here provide a description of a physical mechanism underlying this technique. The findings of this study may aid in deciding whether to bilaterally patch patients and in counseling patients on pre- and postoperative care. PMID:21666245

  20. Ray tracing model for the estimation of power spectral properties in laser Doppler velocimetry of retinal vessels and its potential application to retinal vessel oximetry

    Science.gov (United States)

    Petrig, Benno L.; Follonier, Lysianne

    2005-12-01

    A new model based on ray tracing was developed to estimate power spectral properties in laser Doppler velocimetry of retinal vessels and to predict the effects of laser beam size and eccentricity as well as absorption of laser light by oxygenated and reduced hemoglobin. We describe the model and show that it correctly converges to the traditional rectangular shape of the Doppler shift power spectrum, given the same assumptions, and that reduced beam size and eccentric alignment cause marked alterations in this shape. The changes in the detected total power of the Doppler-shifted light due to light scattering and absorption by blood can also be quantified with this model and may be used to determine the oxygen saturation in retinal arteries and veins. The potential of this approach is that it uses direct measurements of Doppler signals originating from moving red blood cells. This may open new avenues for retinal vessel oximetry.

  1. If I Had - Retinitis Pigmentosa

    Medline Plus

    Full Text Available ... discuss retinitis pigmentosa. Dr. Chader is a Chief Scientist at the Doheny Retina Institute at University of ... with Dr. Gerry Chader, who is the chief scientist at the Doheny Retina Institute at the University ...

  2. Flexible retinal electrode array

    Science.gov (United States)

    Okandan, Murat (Albuquerque, NM); Wessendorf, Kurt O. (Albuquerque, NM); Christenson, Todd R. (Albuquerque, NM)

    2006-10-24

    An electrode array which has applications for neural stimulation and sensing. The electrode array can include a large number of electrodes each of which is flexibly attached to a common substrate using a plurality of springs to allow the electrodes to move independently. The electrode array can be formed from a combination of bulk and surface micromachining, with electrode tips that can include an electroplated metal (e.g. platinum, iridium, gold or titanium) or a metal oxide (e.g. iridium oxide) for biocompatibility. The electrode array can be used to form a part of a neural prosthesis, and is particularly well adapted for use in an implantable retinal prosthesis where the electrodes can be tailored to provide a uniform gentle contact pressure with optional sensing of this contact pressure at one or more of the electrodes.

  3. 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

  4. Retinal Oximetry with 510-600 nm Light Based on Partial Least-Squares Regression Technique

    Science.gov (United States)

    Arimoto, Hidenobu; Furukawa, Hiromitsu

    2010-11-01

    The oxygen saturation distribution in the retinal blood stream is estimated by measuring spectral images and adopting the partial-least squares regression. The wavelengths range used for the calculation is from 510 to 600 nm. The regression model for estimating the retinal oxygen saturation is built on the basis of the arterial and venous blood spectra. The experiment is performed using an originally designed spectral ophthalmoscope. The obtained two-dimensional (2D) oxygen saturation indicates the reasonable oxygen level across the retina. The measurement quality is compared with those obtained using other wavelengths sets and data processing methods.

  5. Retinal vasculitis--a primer.

    OpenAIRE

    Rosenbaum, J T; Robertson, J. E.; Watzke, R. C.

    1991-01-01

    Retinal vasculitis is a diagnosis that is generally suggested by an ophthalmologist. Frequently patients with the disorder are referred to nonophthalmologists for further diagnostic evaluation or treatment. The criteria for defining vasculitis differ greatly between ophthalmologists and other physicians. To facilitate collaboration between ophthalmologists and their colleagues, we have sought to clarify the term "retinal vasculitis" by discussing its subcategories, the potential role of antip...

  6. Retinal vasculitis in rheumatoid arthritis.

    OpenAIRE

    Martin, M F; Scott, D G; GILBERT, C; Dieppe, P.A.; Easty, D L

    1981-01-01

    A woman with exacerbation of severe rheumatoid arthritis developed lesions compatible with retinal vasculitis. Laboratory studies confirmed the diagnosis, and the rapid clinical improvement that accompanied a fall in circulating immune complexes suggested that the vasculitis was a direct consequence of the rheumatoid disease. From these observations retinal vasculitis should probably be sought in any patient with rheumatoid disease and the vasculitis added to the list of ocular complications ...

  7. Adult retinal stem cells revisited.

    OpenAIRE

    Bhatia, B.; Singhal, S; JAYARAM, H; Khaw, P T; Limb, G A

    2010-01-01

    Recent advances in retinal stem cell research have raised the possibility that these cells have the potential to be used to repair or regenerate diseased retina. Various cell sources for replacement of retinal neurons have been identified, including embryonic stem cells, the adult ciliary epithelium, adult Müller stem cells and induced pluripotent stem cells (iPS). However, the true stem cell nature of the ciliary epithelium and its possible application in cell therapies has now been questio...

  8. Retinal implants: a systematic review.

    Science.gov (United States)

    Chuang, Alice T; Margo, Curtis E; Greenberg, Paul B

    2014-07-01

    Retinal implants present an innovative way of restoring sight in degenerative retinal diseases. Previous reviews of research progress were written by groups developing their own devices. This systematic review objectively compares selected models by examining publications describing five representative retinal prostheses: Argus II, Boston Retinal Implant Project, Epi-Ret 3, Intelligent Medical Implants (IMI) and Alpha-IMS (Retina Implant AG). Publications were analysed using three criteria for interim success: clinical availability, vision restoration potential and long-term biocompatibility. Clinical availability: Argus II is the only device with FDA approval. Argus II and Alpha-IMS have both received the European CE Marking. All others are in clinical trials, except the Boston Retinal Implant, which is in animal studies. Vision restoration: resolution theoretically correlates with electrode number. Among devices with external cameras, the Boston Retinal Implant leads with 100 electrodes, followed by Argus II with 60 electrodes and visual acuity of 20/1262. Instead of an external camera, Alpha-IMS uses a photodiode system dependent on natural eye movements and can deliver visual acuity up to 20/546. Long-term compatibility: IMI offers iterative learning; Epi-Ret 3 is a fully intraocular device; Alpha-IMS uses intraocular photosensitive elements. Merging the results of these three criteria, Alpha-IMS is the most likely to achieve long-term success decades later, beyond current clinical availability. PMID:24403565

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

    DEFF Research Database (Denmark)

    Frederiksen, Christian Alcaraz; Jeppesen, Peter

    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 retinopathy, Group D maculopathy not requiring laser treatment. The diameter changes of a large retinal arteriole were measured using the Retinal Vessel Analyzer (RVA, Imedos, Germany) before, during, and after an increase in the blood pressure induced by isometric exercise. Additionally, the retinal thickness was measured using optical coherence tomography scanning. RESULTS: The arterioles contracted during isometric exercise in normal persons (diameter response: -0.70+/-0.48%) and in patients with no retinopathy (-1.15+/-0.44%), but dilated in patients with mild retinopathy (0.41+/-0.49%) and diabetic maculopathy (0.54+/-0.44%), p=0.01. Retinal thickness was normal in Group A (260+/-5.0 microm), Group B (257+/-4.5 microm), and Group C (253+/-4.4 microm), but was significantly (p=0.006) increased in Group D (279+/-5.3 microm). CONCLUSIONS: The diameter response was reduced in type 2 diabetic patients with retinopathy, whereas retinal thickness was increased in patients with diabetic maculopathy. This suggests that impairment of diameter response in retinal arterioles precedes the development of diabetic macular edema.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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...

  16. 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.

  17. Alternative splicing and retinal degeneration.

    Science.gov (United States)

    Liu, M M; Zack, D J

    2013-08-01

    Alternative splicing is highly regulated in tissue-specific and development-specific patterns, and it has been estimated that 15% of disease-causing point mutations affect pre-mRNA splicing. In this review, we consider the cis-acting splice site and trans-acting splicing factor mutations that affect pre-mRNA splicing and contribute to retinal degeneration. Numerous splice site mutations have been identified in retinitis pigmentosa (RP) and various cone-rod dystrophies. Mutations in alternatively spliced retina-specific exons of the widely expressed RPGR and COL2A1 genes lead primarily to X-linked RP and ocular variants of Stickler syndrome, respectively. Furthermore, mutations in general pre-mRNA splicing factors, such as PRPF31, PRPF8, and PRPF3, predominantly cause autosomal dominant RP. These findings suggest an important role for pre-mRNA splicing in retinal homeostasis and the pathogenesis of retinal degenerative diseases. The development of novel therapeutic strategies to modulate aberrant splicing, including small molecule-based therapies, has the potential to lead to new treatments for retinal degenerative diseases. PMID:23647439

  18. Nampt/PBEF/visfatin serum levels: a new biomarker for retinal blood vessel occlusions

    Directory of Open Access Journals (Sweden)

    Kaja S

    2015-04-01

    Full Text Available Simon Kaja,1,* Anna A Shah,1,* Shamim A Haji,1,* Krishna B Patel,1 Yuliya Naumchuk,1 Alexander Zabaneh,1 Bryan C Gerdes,1 Nancy Kunjukunju,1 Nelson R Sabates,1 Michael A Cassell,1 Ron K Lord,1 Kevin P Pikey,1 Abraham Poulose,1 Peter Koulen1,21Vision Research Center, Department of Ophthalmology, 2Department of Basic Medical Science, School of Medicine, University of Missouri – Kansas City, Kansas City, MO, USA*These authors contributed equally to this workAbstract: The main objective of the study was to quantify serum levels of nicotinamide phosphoribosyltransferase (Nampt/pre-B-Cell colony-enhancing factor 1/visfatin in subjects with a history of retinal vascular occlusions (RVOs, disease conditions characterized by pronounced ischemia, and metabolic energy deficits. A case–control study of 18 subjects with a history of RVO as well as six healthy volunteers is presented. Serum Nampt levels were quantified using a commercially available enzyme-linked immunosorbent assay kit. Serum Nampt levels were 79% lower in patients with a history of RVO compared with that in healthy volunteers (P<0.05. There was no statistically significant difference among the types of RVOs, specifically branch retinal vein occlusions (n=7, central retinal vein occlusions (n=5, hemiretinal vein occlusions (n=3, and central retinal artery occlusions (n=3; P=0.69. Further studies are needed to establish the temporal kinetics of Nampt expression and to determine whether Nampt may represent a novel biomarker to identify at-risk populations, or whether it is a druggable target with the potential to ameliorate the long-term complications associated with the condition, ie, macular edema, macular ischemia, neovascularization, and permanent loss of vision.Keywords: Nampt, PBEF, visfatin, nicotinamide phosphoribosyltransferase, pre-B-cell colony-enhancing factor, retinal artery occlusion, retinal vein occlusion, biomarker, retina, vasculature

  19. Crocetin, a carotenoid derivative, inhibits retinal ischemic damage in mice.

    Science.gov (United States)

    Ishizuka, Fumiya; Shimazawa, Masamitsu; Umigai, Naofumi; Ogishima, Hiromi; Nakamura, Shinsuke; Tsuruma, Kazuhiro; Hara, Hideaki

    2013-03-01

    Crocetin, an aglycone of crocin, is found both in the saffron crocus (Crocus starus L.) and in gardenia fruit (Gardenia jasminoides Ellis). We evaluated the protective effects of crocetin against the retinal ischemia induced by 5h unilateral ligation of both the pterygopalatine artery (PPA) and the external carotid artery (ECA) in anesthetized mice. The effects of crocetin (20mg/kg, p.o.) on ischemia/reperfusion-induced retinal damage were examined by histological, electrophysiological, and anti-apoptotic analyses. Data for anti-apoptotic analysis was obtained by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. Using immunohistochemistry and immunoblotting, the protective mechanism mediating the effects of crocetin was evaluated by examining crocetin's effects on the expression of 8-hydroxy-2-deoxyguanosine (8-OHdG; used as a marker of oxidative stress) and on phosphorylations of mitogen-activated protein kinases [MAPK; viz. extracellular signal-regulated protein kinases (ERK), c-Jun N-terminal kinases (JNK) and p38], and the redox-sensitive transcription factors nuclear factor-kappa B (NF-?B) and c-Jun. The histological analysis revealed that ischemia/reperfusion (I/R) decreased the cell number in the ganglion cell layer (GCL) and the thickness of inner nuclear layer (INL), and that crocetin inhibited GCL and INL. ERG measurements revealed that crocetin prevented the I/R-induced reductions in a- and b-wave amplitudes seen at 5 days after I/R. In addition, crocetin decreased the numbers of TUNEL-positive cells and 8-OHdG-positive cells, and the phosphorylation levels of p38, JNK, NF-?B, and c-Jun present in the retina after I/R. These findings indicate that crocetin prevented ischemia-induced retinal damage through its inhibition of oxidative stress. PMID:23428630

  20. 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.

  1. Arterial embolism

    Science.gov (United States)

    ... There may be signs of tissue death or gangrene. Tests to diagnose arterial embolism or reveal the ... or permanent kidney failure Tissue death ( necrosis ) and gangrene Transient ischemic attack (TIA)

  2. Retinal vasculature enhancement using independent component analysis

    Directory of Open Access Journals (Sweden)

    Ahmad Fadzil M. Hani

    2009-11-01

    Full Text Available 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 important to provide better visualization of retinal blood vessels as well as to increase accuracy of retinal vasculature segmentation. Fluorescein angiogram overcomes this imaging problem but it is an invasive procedure that leads to other physiological problems. In this research work, the low contrast problem of retinal fundus images ob-tained from fundus camera is addressed. We develop a fundus image model based on probability distribution function of melanin, haemoglobin and macular pigment to represent melanin, retinal vasculature and macular region, respectively. We determine retinal pigments makeup, namely macular pigment, melanin and haemoglobin using independent component analysis. Independent component image due to haemoglobin obtained is used since it exhibits higher contrast retinal vasculature. Contrast of reti-nal vasculature from independent component image due to haemoglobin is compared to those from other enhancement methods. Results show that this approach outperforms other non-invasive enhancement methods, such as contrast stretching, histogram equalization and CLAHE and can be beneficial for retinal vasculature segmentation. Contrast enhancement factor up to 2.62 for a digital retinal fundus image model is achieved. This improvement in contrast reduces the need of applying contrasting agent on patients.

  3. Alternative splicing and retinal degeneration

    OpenAIRE

    Liu, Melissa M.; Zack, Donald J.

    2013-01-01

    Alternative splicing is highly regulated in tissue-specific and development-specific patterns, and it has been estimated that 15% of disease-causing point mutations affect pre-mRNA splicing. In this review, we consider the cis-acting splice site and trans-acting splicing factor mutations that affect pre-mRNA splicing and contribute to retinal degeneration. Numerous splice site mutations have been identified in retinitis pigmentosa and various cone-rod dystrophies. For example, mutations in al...

  4. 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.

  5. 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)

  6. Erythropoietin administration protects retinal neurons from acute ischemia-reperfusion injury

    OpenAIRE

    Junk, Anna K.; Mammis, Antonios; Savitz, Sean I.; Singh, Manjeet; Roth, Steven; Malhotra, Samit; Rosenbaum, Pearl S.; Cerami, Anthony; Brines, Michael; Rosenbaum, Daniel M.

    2002-01-01

    Erythropoietin (EPO) plays an important role in the brain's response to neuronal injury. Systemic administration of recombinant human EPO (rhEPO) protects neurons from injury after middle cerebral artery occlusion, traumatic brain injury, neuroinflammation, and excitotoxicity. Protection is in part mediated by antiapoptotic mechanisms. We conducted parallel studies of rhEPO in a model of transient global retinal ischemia induced by raising intraocular pressure, which is a clinically relevant ...

  7. Risk factor profile in retinal detachment

    Directory of Open Access Journals (Sweden)

    Azad Raj

    1988-01-01

    Full Text Available 150 cases of retinal detachment comprising 50 patients each of bilateral retinal detachment, unilateral retinal detachment without any retinal lesions in the fellow eve and unilateral retinal detachment with retinal lesions in the fellow eye were studied and the various associated risk factors were statistically analysed. The findings are discussed in relation to their aetiological and prognostic significance in the different types of retinal detachment. Based on these observations certain guidelines are offered which may be of value in decision making, in prophylactic detachment surgery. Tractional breaks in the superior temporal quadrant especially when symptomatic. mandate prophylactic treatment. Urgency is enhanced it? the patient is aphakic. Associated myopia adds to the urgency. The higher incidence of initial right e? e involvement in all groups suggests a vascular original possibly ischaemic.

  8. Pattern of retinal diseases in hilly terrain of Himachal Pradesh, India

    Directory of Open Access Journals (Sweden)

    Anubhav Chauhan

    2014-12-01

    Full Text Available AIM: To study the pattern/distribution of retinal vascular diseases in the hilly terrain of Himachal Pradesh(altitude ranging from 500-4500m above sea level.METHODS: It is a retro/prospective study of patients with retinal diseases attending the general ophthalmology clinic of a tertiary care facility at Shimla from August 2008 to April 2013. Out of 5600 subjects, 4323 were taken as a sample. The data were taken from the hospital records and thereafter analyzed to determine their age, sex distribution and diagnosis. All patients underwent visual acuity, refraction, slit lamp examination and fundus evaluation. The diagnosis was confirmed from fundus clinic records and evaluation of fundus photographic records retro/prospectively. The photographs were taken on the fundus camera(Kowa Fundus Camera VX-10and fundus fluorescein angiography done where ever indicated.RESULTS:Out of the 4323 patients, there were more males 2563(59.29%than females 1760(40.71%with retinal diseases. Out of the 525(12.14%diabetic retinopathy(DRsubjects, mild non-proliferative diabetic retinopathy was present in 133(3.08%, moderate non-proliferative diabetic retinopathy in 156(3.60%, severe non-proliferative diabetic retinopathy in 120(2.78%and proliferative diabetic retinopathy in 116(2.68%subjects. Amongst the 393(9.10%subjects of hypertensive retinopathy, hypertensive retinopathy-grade 1(was present in 130(3.01%, hypertensive retinopathy-grade 2 in 111(2.57%, hypertensive retinopathy-grade 3 in 131(3.03%and hypertensive retinopathy-grade 4 in 21(0.49%subjects. Of all the 660(15.27%subjects of other retinal vascular disorders, branch retinal vein occlusion(BRVOwas present in 229(5.30%, central retinal vein occlusion(CRVOin 55(1.27%, hemi central vein occlusion in 8(0.19%, central retinal artery occlusion(CRAOin 20(0.46%, branch retinal artery occlusion in 4(0.09%, ocular ischaemic syndrome in 1(0.02%, retinopathy of prematurity in 9(0.21%, retinal artery macroaneurysm in 5(0.12%, juxtafoveal telangiectasia in 6(0.14%, anaemic retinopathy in 16(0.37%, leukemic retinopathy in 10(0.23%, preretinal haemorrhage in 52(1.20%, Coats disease in 8(0.19%, cilioretinal artery occlusion in 1(0.02%, Eales disease in 10(0.23%, vasculitis in 17(0.39%and clinically significant macular edema in 209(4.83%subjects.CONCLUSION: DR was the most common retinal vascular disorder. Retinal disorders appear to be a major public health problem in India. The present study shall help us in planning the management of such disorders in the hilly state of Himachal Pradesh to reduce the visual morbidity arising out of such disorders.

  9. 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

  10. 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.

  11. Retinal projections in gymnotid fishes

    International Nuclear Information System (INIS)

    Retinal projections were studied in four species of gymnotid fishes, Gymnotus carapo, Hypopomus artedi, Eigenmannia virescens and Sternopygus sp. with the aid of cobalt or horseradish peroxidase labelling and autoradiographic techniques. The optic tract gives off a small branch, the axial optic tract and then, after crossing in the midline, splits into a dorsomedial, dorsal and ventral fascicle. E. virescens and Sternopygys sp. display in addition an accessory optic tract. In all four species retinal projections are bilateral; ipsilateral projections, however, are extremely sparse. In all four species, the retinal fibres terminate bilaterally in the suprachiasmatic nucleus, dorsolateral optic nucleus of the thalamus and the optic nucleus of the posterior commissure; a bilateral retinotectal projection was only found in E. virescens and G. carapo. Retinal projections are only contralateral to the ventromedical nucleus of the thalamus, the central pretectal nucleus and the accessory optic nucleus. The contralateral retinotectal fibres terminate in the stratum fibrosum and griseum superficiale, and in the stratum album centrale and stratum periventriculare. A small accessory optic tract and nucleus were detected in E. virescens and Sternopygys sp. but not in G. carapo and H. artedi. The results indicate that the visual system of gymnotid fish is as simple as that of mormyrids. The poor visibility in the environment where these animals live and the additional sensory systimals live and the additional sensory system which these animals possess may explain the poor development of the visual system. (author)

  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 low cost and simple technique

  13. 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.

  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. Pulmonary Arterial Hypertension (PAH)

    Science.gov (United States)

    ... the arteries of the lungs. Pulmonary arterial hypertension (PAH) is one form of pulmonary hypertension. Pulmonary arteries ... oxygen to be delivered throughout your body. In PAH, the pulmonary arteries constrict abnormally. This forces your ...

  16. Coronary Artery Bypass Grafting

    Science.gov (United States)

    ... from the NHLBI on Twitter. What Is Coronary Artery Bypass Grafting? Coronary artery bypass grafting (CABG) is ... bypass multiple coronary arteries during one surgery. Coronary Artery Bypass Grafting Figure A shows the location of ...

  17. The porcine retinal vasculature accessed using an endovascular approach : a new experimental model for retinal ischemia

    DEFF Research Database (Denmark)

    Morén, Håkan; Undrén, Per

    2009-01-01

    The aim of this study was to examine whether the retinal circulation in the pig can be accessed using interventional neuroradiology and to explore the possibility of creating occlusions that result in experimental retinal ischemia.

  18. Cytomegalovirus Retinitis After Intravitreous Triamcinolone Injection in a Patient with Central Retinal Vein Occlusion

    OpenAIRE

    Park, Yong-Sik; Byeon, Suk Ho

    2008-01-01

    To report a case of cytomegalovirus (CMV) retinitis after intravitreal injection of triamcinolone acetonide (IVTA). A 77-year-old woman with macular edema due to central retinal vein occlusion (CRVO) developed peripheral retinitis 4 months after IVTA. A diagnostic anterior chamber paracentesis was performed to obtain DNA for a polymerase chain reaction (PCR) test for viral retinitis. The PCR test was positive for CMV DNA. Other tests for infective uveitis and immune competence were negative. ...

  19. Differential diameter responses in macular and peripheral retinal arterioles may contribute to the regional distribution of diabetic retinopathy lesions

    DEFF Research Database (Denmark)

    Skov Jensen, Peter; Jeppesen, Peter

    2011-01-01

    BACKGROUND: Diabetic retinopathy is assumed to be due to impaired retinal autoregulation, involving both pressure autoregulation and metabolic autoregulation. The disease displays regional differences, with signs of hyperperfusion in the macular area and capillary occlusion with retinal ischemia in the peripheral retinal areas. It can be hypothesized that these regional differences in the occurrence of retinopathy lesions may reflect differences in the capacity of retinal arterioles to autoregulate the diameter of retinal arterioles. METHODS: Seventeen normal persons and two matched groups of patients with respectively diabetic maculopathy and proliferative diabetic retinopathy were examined. The diameter change of a macular and a peripheral retinal arteriole during an increase in the arterial blood pressure induced by isometric exercise, during an increase in retinal metabolism induced by flicker stimulation, and during both stimulus paradigms simultaneously were studied using the dynamic vessel analyzer (DVA). RESULTS: During isometric exercise, the diameter response was reduced in both macular and peripheral retinal arterioles in the two groups of patients with diabetes mellitus. During flicker stimulation, the diameter response was significantly reduced in patients with proliferative diabetic retinopathy, but there was no significant difference between the responses of macular and peripheral arterioles. During simultaneous isometric exercise and flicker stimulation, there was no difference between the diameter response of macular arterioles in the three groups, whereas the diameter response of macular arterioles was significantly lower in normal persons and significantly higher in persons with proliferative diabetic retinopathy as compared to peripheral arterioles. CONCLUSIONS: Regional differences in the disturbances of the diameter response to increased blood pressure may contribute to the regional differences in the distribution of diabetic retinopathy lesions. In the central retinal areas, the diameter response to increased blood pressure and retinal metabolism interacted in a way that may potentially protect this area from ischaemia, whereas this protective mechanism was absent in the peripheral retinal arterioles. An elucidation of the mechanisms underlying diameter regulation to increased blood pressure and retinal metabolism, and the interaction between these two mechanisms, may help in understanding the pathophysiology of diabetic retinopathy.

  20. 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

  1. Postocclusive Reactive Hyperemia Occurs in the Rat Retinal Circulation but Not in the Choroid

    Science.gov (United States)

    Li, Guang; Kiel, Jeffrey W.; Cardenas, Damon P.; De La Garza, Bryan H.; Duong, Timothy Q.

    2013-01-01

    Purpose. We tested the hypothesis that retinal blood flow has a postocclusive reactive hyperemia response modulated by occlusion duration and metabolic activity, and that choroidal blood flow does not. Methods. Anesthetized and paralyzed rats (n = 34) were studied. Retinal and choroidal blood flow was measured by laser speckle imaging and laser Doppler flowmetry, respectively. Blood oxygenation level–dependent functional magnetic resonance imaging (BOLD fMRI) was used to measure changes in relative blood oxygenation of the retinal and choroidal circulations. Transient carotid occlusion was elicited with a hydraulic occluder on the common carotid artery. Several occlusion durations were tested during dark, constant light, and flicker light conditions to modulate metabolic demand. The hyperemia response magnitude was quantified by integrating the area above the blood flow baseline for the 3 minutes after release of the occlusion. Results. Systemic arterial pressure (108.2 ± 1.4 mm Hg) was unaffected by the carotid occlusions, and was similar among animals and conditions. Retinal blood flow had a reactive hyperemia, but choroidal blood flow did not (e.g., 14 ± 2%•sec versus 0.5 ± 4%•sec after 60-second occlusion). The hyperemia magnitude increased as a nonlinear function of occlusion duration and reached a plateau at occlusion durations <60 second. The hyperemia magnitude was not altered by different lighting conditions at occlusion durations of 15 and 60 seconds. BOLD fMRI results were similar to the laser-based blood flow measurements. Conclusions. The results indicate that metabolic local control has a negligible role in choroidal blood flow regulation and only partially accounts for the blood flow behavior in the retinal circulation. PMID:23821190

  2. 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...

  3. Intraocular pressure in retinal vein occlusion.

    OpenAIRE

    Frucht, J.; Shapiro, A.; Merin, S.

    1984-01-01

    The intraocular pressure of 59 patients with retinal vein occlusion was studied. Central retinal vein occlusion (CVO) was diagnosed in 24 patients and branch retinal vein occlusion (BVO) was diagnosed in the rest. The intraocular pressure of a sex and age matched group of controls was also studied for comparison. The intraocular pressure in the CVO group were significantly different from those of the matched controls (p less than 0.001). A statistically significant difference of a lesser degr...

  4. [Novel mechanism for retinal vascular diseases].

    Science.gov (United States)

    Suzuma, Kiyoshi

    2015-03-01

    I. A new therapeutic target for diabetic retinopathy. Recent reports state that succinate may be an independent retinal angiogenic factor. We evaluated concentrations in vitreous from proliferative diabetic retinopathy (PDR), and found that succinate increased significantly in PDR. Interestingly, levels of succinate from bevacizumab-pre-injected PDR were normal, suggesting that vascular endothelial growth factor (VEGF) had a positive feedback mechanism for succinate since succinate was previously reported to induce VEGF. II. A new understanding of central retinal vein occlusion (CRVO). We evaluated retinal blood flow velocity with laser speckle flowgraphy (LSFG) made in Japan, and found that cases in which both macular edema and retinal blood flow velocity improved after anti-VEGF therapy had better prognosis. In ischemic CRVO at final visit, mean retinal blood velocity was less than 50% of fellow eyes after 1st anti-VEGF therapy, suggesting that those cases might have poor prognosis. LSFG is useful for evaluation and decision in CRVO treatment. III. From exploration for mechanism in retinal vascular diseases to re-vascularization therapy. The standard treatment for retinal non-perfusion area is scatter laser photocoagulation, which is both invasive of the peripheral retina and may prove destructive. Re-vascularization is an ideal strategy for treatment of retinal non-perfusion area. To develop a new methods for re-vascularization in retinal non-perfusion area, we have designed experiments using a retina without vasculature differentiated from induced pluripotent stem(iPS) cells. PMID:25854111

  5. Cell transplantation strategies for retinal repair.

    Science.gov (United States)

    West, E L; Pearson, R A; MacLaren, R E; Sowden, J C; Ali, R R

    2009-01-01

    Cell transplantation is a novel therapeutic strategy to restore visual responses to the degenerate adult neural retina and represents an exciting area of regenerative neurotherapy. So far, it has been shown that transplanted postmitotic photoreceptor precursors are able to functionally integrate into the adult mouse neural retina. In this review, we discuss the differentiation of photoreceptor cells from both adult and embryonic-derived stem cells and their potential for retinal cell transplantation. We also discuss the strategies used to overcome barriers present in the degenerate neural retina and improve retinal cell integration. Finally, we consider the future translation of retinal cell therapy as a therapeutic strategy to treat retinal degeneration. PMID:19660645

  6. 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.

  7. Prothrombin time in retinitis pigmentosa

    OpenAIRE

    Vinchurkar Manisha

    1998-01-01

    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.

  8. Radiological review of intercostal artery: anatomical considerations when performing procedures via intercostal space

    International Nuclear Information System (INIS)

    The aim of this study was to closely examine the course of the intercostal arteries within the intercostal spaces particularly with regard to where the arteries were located in relation to their adjacent ribs. The degree of tortuosity of the arteries was also examined, along with anatomical differences in different age groups. A total of 81 patients between the age of 30 and 90 years who had underwent a CT examination of the chest for any indication were included in the study. All studies were performed on a dual source 64 slice CT (Siemens Definition Erlangen Germany). Analysis of the intercostal arteries was performed on a CT workstation using volume rendered 3D reconstructions F, or each patient the 10'n intercostals pacesb ilaterally were examined for the course and tortuosity of the intercostal arteries. The ICA is located relatively inferiorly in the intercostal space at costovertebral junction and it gradually becomes more superiorly positioned within the intercostal space it as courses laterally. This finding was consistent in all age groups. In addition, analysis of the data demonstrated increasing intercostal artery tortuosity with advancing age. In this study we have examined the course of the posterior intercostal arteries using MDCT. This study confirms the classical description of the course of ICA. We have shown that in the medial chest, posteriorly, the artery is located in the inferior half of the intercostal space. As it moves away from the costovertebral junction it travels closer to the inferior border of the rib above and reaches the intercostal groove. We have also shown that the artery tends to be more tortuous in elderly patients, decreasing the area of 'safe' space for interventions. Both of these findings are relevant to radiologists and non-radiologists performing interventional procedures via the intercostal space.

  9. Role of Bedside Ultrasound in CMV Retinitis: A Case Report

    OpenAIRE

    Lauren Westafer; L. Connor Nickels; Eike Flach; Giuliano De Portu; Latha Ganti Stead

    2012-01-01

    We present a case of retinal detachment diagnosed by emergency department bedside ultrasonography in a patient with CMV retinitis. The indications and findings of ocular ultrasonography are discussed.

  10. Cone pathway function in relation to asymmetric carotid artery stenosis : correlation to blood pressure

    DEFF Research Database (Denmark)

    Kofoed, Peter Kristian; Munch, Inger Christine

    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 3.4% and 2.0% longer (p?=?0.013 and 0.021), and N1 and P1 amplitudes were 18.0% and 16.0% (p?=?0.0041 and 0.020) lower in eyes on the side with the higher stenosis compared with the contralateral eyes. Shorter implicit times and higher amplitudes were correlated with higher brachial systolic arterial blood pressure (p?=?0.0028, 0.011, 0.041 for N1, P1, N2 implicit times, respectively, and p?=?0.0086, 0.016, 0.040 for N1, P1, N2 for amplitudes, respectively, corrected for OSP). Conclusion:  Cone function deviation was observed in clinically healthy eyes on the side with highest degree of carotid artery stenosis and was found correlated to arterial blood pressure.

  11. 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.

  12. Retinal vein occlusion: pathophysiology and treatment options

    OpenAIRE

    Niral Karia

    2010-01-01

    Niral KariaDepartment of Ophthalmology, Southend Hospital, Prittlewell Chase, Westcliff on Sea, Essex, United KingdomAbstract: This paper reviews the current thinking about retinal vein occlusion. It gives an overview of its pathophysiology and discusses the evidence behind the various established and emerging treatment paradigms.Keywords: central, hemispheric, branch, retinal vein occlusion, visual loss

  13. 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.

  14. Retinal vessel diameters decrease with macular ganglion cell layer thickness in autosomal dominant optic atrophy and in healthy subjects

    DEFF Research Database (Denmark)

    Rönnbäck, Cecilia; GrØnskov, Karen

    2014-01-01

    PURPOSE: To investigate retinal trunk vessel diameters in subjects with autosomal dominant optic atrophy (ADOA) and mutation-free healthy relatives. METHODS: This cross-sectional study included 52 ADOA patients with the optic atrophy 1 (OPA1) exon 28 (c.2826_2836delinsGGATGCTCCA) mutation (age 8.6-83.5 years) (best-corrected visual acuity (BCVA) 8-94 Early Treatment Diabetic Retinopathy Study (ETDRS) letters) and 55 mutation-free first-degree healthy relatives (age 8.9-68.7 years, BCVA 80-99). Analysis of fundus photographs provided integrated magnification-corrected measures of retinal vessel diameters (central retinal artery equivalent, CRAE, and central retinal vein equivalent, CRVE). Statistical analysis was corrected for age, gender, spherical equivalent refraction, axial length and mean arterial blood pressure (MABP) in a mixed model analysis. RESULTS: Retinal arteries and veins were thinner in ADOA than in healthy controls (CRAE (mean ± 2 standard deviations (SD)) 153.9 ± 41.0 ?m and CRVE 236.1 ± 42.0 ?m in ADOA, CRAE 172.5 ± 25.0 ?m (p = 0.0004) and CRVE 254.2 ± 37.6 ?m (p = 0.0019) in healthy controls). MABP was comparable in the two groups (p = 0.18), and in both groups, CRAE decreased with increasing MABP (p = 0.01 and p < 0.0001, respectively). In ADOA, CRAE and CRVE decreased with age (p = 0.011 and p = 0.020, respectively) and CRAE decreased with decreasing BCVA (p = 0.011). In patients with ADOA and in healthy controls, CRAE decreased with decreasing average macular ganglion cell-inner plexiform layer (GC-IPL) thickness (p = 0.0017 and p = 0.0057, respectively). CONCLUSION: Narrow retinal arteries and veins were associated not only with the severity of ADOA but with ganglion cell volume in patients with ADOA and in healthy subjects. This suggests that narrow vessels are a consequence rather than the cause of inner retinal hypoplasia or atrophy, although longitudinal studies are needed to confirm this hypothesis.

  15. Nampt/PBEF/visfatin serum levels: a new biomarker for retinal blood vessel occlusions.

    Science.gov (United States)

    Kaja, Simon; Shah, Anna A; Haji, Shamim A; Patel, Krishna B; Naumchuk, Yuliya; Zabaneh, Alexander; Gerdes, Bryan C; Kunjukunju, Nancy; Sabates, Nelson R; Cassell, Michael A; Lord, Ron K; Pikey, Kevin P; Poulose, Abraham; Koulen, Peter

    2015-01-01

    The main objective of the study was to quantify serum levels of nicotinamide phosphoribosyltransferase (Nampt/pre-B-Cell colony-enhancing factor 1/visfatin) in subjects with a history of retinal vascular occlusions (RVOs), disease conditions characterized by pronounced ischemia, and metabolic energy deficits. A case-control study of 18 subjects with a history of RVO as well as six healthy volunteers is presented. Serum Nampt levels were quantified using a commercially available enzyme-linked immunosorbent assay kit. Serum Nampt levels were 79% lower in patients with a history of RVO compared with that in healthy volunteers (P<0.05). There was no statistically significant difference among the types of RVOs, specifically branch retinal vein occlusions (n=7), central retinal vein occlusions (n=5), hemiretinal vein occlusions (n=3), and central retinal artery occlusions (n=3; P=0.69). Further studies are needed to establish the temporal kinetics of Nampt expression and to determine whether Nampt may represent a novel biomarker to identify at-risk populations, or whether it is a druggable target with the potential to ameliorate the long-term complications associated with the condition, ie, macular edema, macular ischemia, neovascularization, and permanent loss of vision. PMID:25897200

  16. 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 pigs. Conclusions: Guinea pigs are an appropriate and feasible model for UAE with TAGM.

  17. Carotid Artery Screening

    Science.gov (United States)

    Carotid Artery Screening What is carotid artery screening? Who should consider heart screening – and why? How are the procedures ... more information about heart screening? What is carotid artery screening? Screening examinations are tests performed to find ...

  18. 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 ).

  19. Uterine artery embolization with Pingyangmycin lipiodol emulsion for treatment of symptomatic uterine fibroids

    International Nuclear Information System (INIS)

    Objective: To evaluate the effectiveness and side effects of uterine arterial embolization with Pingyangmycin(a homogenous bleomycin) lipiodol emulsion(PLE) for symptomatic uterine fibroids. Methods: Uterine arterial embolization with PLE was performed in 25 patients. The improvement of symptoms and uterine size changes were followed up in 3-18 months(mean 6 months) after the procedure. Results: All but 2 cases were successfully treated bilaterally. Super-selective angiography showed enlargement of uterine artery, accompanied by tortuous branches. The uterine size was increased. The uterus itself was significantly stained and emptied slowly. Coagulation necrosis was found in resected fibroids after embolization in 3 patients. One month after the procedure, a mean 40% reduction of uterine volume was obtained in 18 followed-up cases. The clinical symptoms were relieved significantly. The main side effects were hypogastric pain(13/25),which was intense in 6 cases. Conclusion: Uterine arterial embolization with PLE is a good non-surgical therapy in symptomatic uterine fibroids with mild side effects

  20. 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

  1. Perisaccadic stereo depth with zero retinal disparity.

    Science.gov (United States)

    Zhang, Zhi-Lei; Cantor, Christopher R L; Schor, Clifton M

    2010-07-13

    When an object is viewed binocularly, unequal perspective projections of the two eyes' half images (binocular disparity) provide a cue for the sensation of stereo depth. For almost 200 years, binocular disparity has remained synonymous with retinal disparity, which is computed by subtracting the distance of each half image from its respective fovea. However, binocular disparity could also be coded in headcentric instead of retinal coordinates, by combining eye position and retinal image position in each eye and representing disparity as differences between visual directions of half images relative to the head. Although these two disparity-coding schemes suggest very different neural mechanisms, both offer identical predictions for stereopsis in almost every viewing condition, making it difficult to empirically distinguish between them. We designed a novel stimulus that uses perisaccadic spatial distortion to generate inconsistency between headcentric and retinal disparity. Foveal half images flashed asynchronously just before a horizontal saccade have zero retinal disparity, yet they produce a sensation of depth consistent with a nonzero headcentric disparity. Furthermore, this headcentric disparity can cancel and reverse the perceived depth stimulated with nonzero retinal disparity. This is the first demonstration that a coding scheme other than retinal disparity has a role in human stereopsis. PMID:20619816

  2. Isolation of the retinal isomers from the isomerization of all-trans-retinal by flash countercurrent chromatography.

    Science.gov (United States)

    He, Minfei; Du, Wenkai; Du, Qingbao; Zhang, Yun; Li, Bo; Ke, Changqian; Ye, Yang; Du, Qizhen

    2013-01-01

    The isolation of the retinal isomers from all-trans-retinal was performed by flash countercurrent chromatography. In each separation, isomerization reaction solution of 200mg all-trans-retinal could be loaded on a 1200 mL of high-speed countercurrent chromatographic column with 5mm bore, eluted by a mobile phase flow rate of 25 mL/min, resulting in 63 mg of 11-cis-retinal, 24 mg of 13-cis-retinal and 26 mg of 9-cis-retinal with purities more than 95%. n-Hexane-acetonitrile (3:1) was used as the solvent system which possesses the advantages of simplicity, re-use of the solvent and multiple injections. This method could be used to prepare 13-cis-retinal, 11-cis-retinal and 9-cis-retinal for the photoisomerization investigation, such as the effect of 11-cis-retinal in the visual system. PMID:23219476

  3. Retinal Vessels Change in Primary Angle-Closure Glaucoma: The Handan Eye Study

    Science.gov (United States)

    Gao, Jianlu; Liang, Yuanbo; Wang, Fenghua; Shen, Ran; Wong, Tienyin; Peng, Yi; Friedman, David S.; Wang, Ningli

    2015-01-01

    Glaucoma is the second leading cause of blindness worldwide. To examine the relationship between angle closure and the retinal vessel diameter in Chinese adults, we conducted Handan Eye Study (HES), a large population-based cross-sectional study, which enrolled 6830 participants >30 year-old living in 13 randomly selected villages of Yongnian County. After adjusting for age, gender, spherical equivalent (SE), diabetes, and hypertension, the mean central retinal artery equivalent (CRAE, ?m) was 127.1 ± 7.0 and 145.6 ± 4.4 in primary open-angle glaucoma (POAG) and primary angle closure glaucoma (PACG), respectively; narrower than that in normal control (156.1 ± 0.4), primary angle-closure suspect (PACS) (156.3 ± 1.1) or primary angle closure (PAC) (156.0 ± 3.4) (P = 0.001). The mean central retinal vein equivalent (CRVE, ?m) was 229.0 ± 5.9 and 215.8 ± 9.5 in POAG and PACG, respectively; narrower than that in normal control (238.3 ± 0.5), PACS (241.2 ± 1.4) or PAC (242.2 ± 4.6) (P = 0.001). There was no significant difference in the mean CRAE or CRVE between PACG and POAG. Compared to the normal control (0.66), the mean arterio-venous ratio (AVR) was smaller in POAG (0.64) and PACG (0.59), whereas larger in PACS (0.65) and PAC (0.67) (P = 0.003). To conclude, PACG and POAG individuals have narrower retinal arteries and veins. PMID:25928115

  4. The Development of Human Organotypic Retinal Cultures (HORCs) to study Retinal Neurodegeneration

    OpenAIRE

    Niyadurupola, Nuwan; Sidaway, Peter; Osborne, Andrew; Broadway, David C.; Sanderson, Julie

    2010-01-01

    Abstract Aims To develop human organotypic retinal cultures (HORCs) to study retinal ganglion cell (RGC) death in response to ischaemic and N-methyl-D-aspartate (NMDA) excitotoxic insults, both known to cause loss of RGCs and proposed as mechanisms involved in glaucomatous retinal neurodegeneration. Methods Human donor eyes were obtained within 24hr post mortem. The retina was isolated and explants cultured using two techniques. THY-1 mRNA (as assessed by real time quantitativ...

  5. Computational molecular phenotyping of retinal sheet transplants to rats with retinal degeneration

    OpenAIRE

    Seiler, M.J.; Jones, B W; Aramant, R.B.; Yang, P.B.; Keirstead, H.S.; Marc, R.E.

    2012-01-01

    Retinal progenitor sheet transplants have been shown to extend neuronal processes into a degenerating host retina and to restore visual responses in the brain. The aim of this study was the first attempt to identify cells involved in transplant signals to retinal degenerate hosts using computational molecular phenotyping (CMP). - S334ter line 3 rats received fetal retinal sheet transplants at the age of 24-40d. Donor tissues were incubated with slow-releasing microspheres containing BDNF or G...

  6. 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.

  7. Chickenpox-associated acute retinal necrosis syndrome.

    Science.gov (United States)

    Culbertson, W W; Brod, R D; Flynn, H W; Taylor, B C; Brod, B A; Lightman, D A; Gordon, G

    1991-11-01

    Acute retinal necrosis (ARN) syndrome usually occurs as the result of secondary reactivation of latent, previously acquired, varicella-zoster or herpes simplex virus. The authors report four patients who developed a mild form of ARN within 1 month (5 to 28 days) after the onset of chickenpox. In contrast to typical cases of ARN, these cases were less severe, with retinitis limited to two quadrants or less (three patients), no retinal detachment (four patients), minimal vitreitis (four patients), and no loss of visual acuity (four patients). Thus, ARN may occur during the course of primary varicella-zoster infection. PMID:1666176

  8. Novel method of chronically blocking retinal activity.

    Science.gov (United States)

    Prusky, G T; Ramoa, A S

    1999-02-01

    The ethylene-vinyl acetate copolymer Elvax has been used as a vehicle to deliver bioactive substances to discrete areas of the nervous system. Here we report a novel use of Elvax to chronically block retinal activity. Small pieces of Elvax containing the sodium channel blocker tetrodotoxin (TTX) were surgically implanted into the vitreous humor of ferret eyes. Observations of the light-induced pupillary reflex combined with electrophysiological assays of vitreous humor confirmed that these implants completely blocked retinal activity for up to 25 days without apparent retinal damage. The advantages of this procedure over previous methods requiring multiple daily injections of TTX, and alternative experimental applications are discussed. PMID:10065999

  9. Massive hemoptysis due to pulmonary tuberculosis: management with bronchial artery embolization

    International Nuclear Information System (INIS)

    Objective: To evaluate the clinical effects of interventional bronchial artery embolization in the management of massive hemoptysis as a complication of pulmonary tuberculosis. Methods: Interventional bronchial arterial embolization was performed in 26 cases with secondary pulmonary tuberculosis and massive hemoptysis. Tuberculosis was found in bilateral lung in 20 cases out of 26. Unilateral lung was evolved in the rest 6. The dose of hemoptysis was 200 ml/d-1200 ml/d. Bronchial arteriography was undertaken and the target blood vessel was confirmed in all patients. Then PVA grain or silk segment (1-2 mm) were injected into bronchial artery until blood flow was blocked. The procedures were guided under the fluoroscopy. Gelfoam particles were used in 2 cases when tortuous feeding arteries were revealed in angiogram. Results: Bleeding was demonstrated in 58 branches of bronchial artery in all cases. 19 cases were bilateral and 7 unilateral. After the primary intervention, hemoptysis was controlled completely in 23 patients, slight hemoptysis was noted in 2 patients, and no improvement was obtained in one patient. The short term efficiency was 96.1%. No serious complication occurred. In a post-interventional follow up of 6 months to 6 years, 3 patients had relapse after 6 months and reembolization with silk segments was done. The other 23 patients were in stable condition. Long-term efficiency was 88.4%. Conclusion: Embolization of bronchial artery with PVA grain or withof bronchial artery with PVA grain or with silk segments is an effective and safe method in the management of hemoptysis as a complication of pulmonary tuberculosis, especially in patients with severe hemoptysis. The anti-tuberculosis chemotherapy is helpful in preventing the relapse. (authors)

  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. Structural and functional changes in retinal vasculature induced by retinal ischemia-reperfusion in rats.

    Science.gov (United States)

    Nakahara, Tsutomu; Hoshino, Maya; Hoshino, Shin-Ichiro; Mori, Asami; Sakamoto, Kenji; Ishii, Kunio

    2015-06-01

    Recent studies have shown retinal blood vessel damage in experimental models of retinal degeneration. The present study aimed to provide a detailed description of the structural and functional changes in retinal vasculature induced by retinal ischemia-reperfusion (I/R) in rats. Retinal ischemia was induced for 60 min by raising the intraocular pressure to 130 mmHg. Morphological changes in vascular components (endothelial cells, pericytes, and basement membranes), the patency and perfusion of blood vessels, and expression of vascular endothelial growth factor (VEGF) were assessed in the retinas at 2, 7, and 14 days after I/R. Significant reductions in vascular densities were observed at 7 and 14 days after I/R. Pericyte loss occurred after the appearance of endothelial cell degeneration, whereas the vascular basement membranes remained unchanged. Some vessels showed no perfusion in damaged retina. A decrease in the immunoreactivity of VEGF in the region extending from the ganglion cell layer to the outer plexiform layer was evident 2 days after I/R. In retinal I/R model, retinal ganglion cells are rapidly (current results suggest that neuronal cell damage precedes capillary degeneration, and neuronal cells may play an important role in maintaining vascular structure and function through the production and release of endothelial cell survival factors, including VEGF. Neuronal cell damage could be an additional cause of progression of ischemic retinal damage by reducing blood supply to the retinal neurons due to the destruction of the blood vessel network. PMID:25728136

  12. Initial report of quantification of retinal blood flow velocity in normal human subjects using the Retinal Functional Imager (RFI).

    Science.gov (United States)

    Landa, Gennady; Jangi, Anisha A; Garcia, Patricia M T; Rosen, Richard B

    2012-06-01

    The Retinal Functional Imager (RFI) is a novel method for assessing retinal blood flow (RBF) velocity. The purpose of this study was to evaluate RBF velocities in normal human retinas using the RFI. RBF velocity measurements were performed in normal subjects using the RFI (Optical Imaging Ltd., Rehovot, Israel) at the Retina Center of The New York Eye and Ear Infirmary, New York, USA. Using proprietary software processing, the characteristics of the RBF were visualized and measured. The study population comprised fifty-four eyes of 27 normal subjects (20 male and 34 female). The average arterial blood flow velocity was 4.6 ± 0.6 mm/s in males and 4.8 ± 0.7 mm/s in females (the difference was not statistically significant, p value = 0.27). The average venous blood flow velocity was 3.8 ± 0.5 mm/s in males and 3.6 ± 0.4 mm/s in females (the difference again was not statistically significant, p value = 0.11). The average arterial blood flow velocity was 4.8 ± 0.5 mm/s in the right eye and 4.6 ± 0.7 mm/s in the left eye. The average venous blood flow velocity was 3.7 ± 0.4 mm/s in the right eye and 3.6 ± 0.3 mm/s in the left eye. Venous and arterial blood flow velocities were found to be faster in the right eye than in the left eye in our sample, but the differences were not statistically significant (p value = 0.53 and 0.33, respectively). This is the first report of quantification of the RBF using the RFI. The RFI appears to be an effective tool in quantitative evaluations of RBF velocities. The values from the study constitute a normative database which can be used to evaluate and compare eyes with known or suspected pathology. PMID:22484724

  13. [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

  14. Cleavage of ?-Carotene to Retinal

    Science.gov (United States)

    Wyss, Adrian; von Lintig, Johannes

    Elucidating the physiological roles played by vitamins has always been a major goal of nutritionists and biochemists. In humans, vitamin A deficiency disorder (VADD) in milder forms leads to night blindness, whilst more severe progression can lead to corneal malformations, e.g. xerophthalmia (See Volume 5, Chapters 8 and 9). This deficiency also affects the immune system, leads to infertility and causes malformations during embryogenesis. The molecular basis for these diverse effects lies in the dual role of vitamin A (retinol, 1) derivatives. In all visual systems, retinal (2), or a closely related compound such as 3-hydroxyretinal (3), is the chromophore of the visual pigments (e.g. rhodopsin) [1,2]. In vertebrates, the derivative retinoic acid (RA, 4) is a major signalling molecule that controls a wide range of processes. Retinoic acid is the ligand of the nuclear retinoic acid receptors (RARs) and retinoid X receptors (RXRs) [3-6] (see Chapter 15).

  15. Neurogenin3 promotes early retinal neurogenesis

    OpenAIRE

    Ma, Wenxin; Yan, Run-Tao; Mao, Weiming; Wang, Shu-Zhen

    2008-01-01

    The transcriptional regulatory network governing the establishment of retinal neuron diversity is not well delineated. We report experimental results suggesting proneural gene neurogenin3 (ngn3) participating in this regulatory network. Retinal expression of chick ngn3 was confined to early neurogenesis. Overexpression of ngn3 in chick retina reduced cell proliferation and expanded the population of ganglion cells into the territory normally occupied by amacrine cells. Ngn3 overexpression alt...

  16. Retinal haemorrhages in vacuum extraction deliveries

    OpenAIRE

    Bahgat Mostafa

    1987-01-01

    Two hundred and thirty eight newly born infants were subjected to fundus examination in the first 5 hours of labour then daily till discharge from the hospital then weekly till complete absorption of retinal haemorrhages The 238 infants were 23 delivered by caesarean section, 90 with spontaneous vaginal delivery,45 babies (over3.5 kgm) delivered vaginallyand80 delivered by vacuum extraction. It was found that 37.39% of the newborns had retinal haemorrhages. The incidence, type and seve...

  17. Molecular beams of polyenes: Retinals and ?-carotene

    Science.gov (United States)

    Dey, M.; Moritz, F.; Atkinson, G. H.; Grotemeyer, J.; Schlag, E.

    1991-09-01

    Low temperature, molecular beams of polyenes (retinol, retinal, a Schiff base retinal, and ?-carotene) are formed in jet expansions by CO2 laser-induced desorption from a deposited solid surface. Mass spectra of these intact polyenes are detected by resonantly-enhanced ionization mass spectrometry. Laser-desorption conditions which produce essentially no polyene fragmentation are obtained by controlling the focusing conditions of the CO2 laser on the deposited sample.

  18. Dynamic eye phantom for retinal oximetry measurements

    OpenAIRE

    Lemaillet, Paul; Jessica C. Ramella-Roman

    2009-01-01

    Measurements of oxygen saturation and flow in the retina can yield information about eye health and the onset of eye pathologies such as diabetic retinopathy. Recently, we developed a multiaperture camera that uses the division of the retinal image into several wavelength-sensitive subimages to compute retinal oxygen saturation. The calibration of such instruments is particularly difficult due to the layered structure of the eye and the lack of alternative measurement techniques. For this pur...

  19. Marfan Syndrome Presenting with Bilateral Retinal Detachment

    OpenAIRE

    Subrata Chakrabarti; Koushik Pan

    2014-01-01

    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...

  20. 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.

  1. Timing of retinal vein occlusion laser photocoagulation

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2014-08-01

    Full Text Available AIM:To observe the clinical curative effect of different duration of retinal vein occlusion(RVOby laser photocoagulation treatment, discuss the timing of the RVO laser photocoagulation treatment, provide the basis for clinical choice of RVO photocoagulation treatment time. METHODS: Retrospective analysis. Line selection retinal laser photocoagulation treatment for 103 cases(103 eyeswith RVO, patients were divided into three groups according to the onset time. In group A(46 eyes, course ?1mo, 28 eyes with branch retinal vein occlusion(BRVO, 18 eyes with central retinal vein occlusion(CRVO; 30 eyes were ischemic RVO, 16 eyes were non-ischemic RVO. In group B(38 eyes, 1moRESULTS: The best corrected visual acuity improved rate, retinal hemorrhage, macular edema, absorption, macular center concave thickness decreased of patients with different course after RVO photocoagulation treatment, the early group was better than that of the late, non-ischemic RVO was better than that of ischemic RVO, laser photocoagulation treatment effect BRVO was better than that of CRVO and the difference was statistically significant(PCONCLUSION: RVO laser photocoagulation in the early intervention treatment can accelerate the retinal hemorrhage, macular edema, absorption, effectively protect the patient's existing vision, improve the long-term vision, and has a certain clinical practical significance.

  2. 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 retina 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)

  3. Expression of peptide NAP in rat retinal Müller cells prevents hypoxia-induced retinal injuries and promotes retinal neurons growth.

    Science.gov (United States)

    Zheng, Yuping; Zeng, Hao; She, Huaning; Liu, Hui; Sun, Naixue

    2010-07-01

    NAP (NAPVSIPQ) is a short peptide derived from activity-dependent neuroprotective protein (ADNP) sequence, whose potent and direct neuroprotective capabilities have been widely accepted. However, due to the high risk and inconvenience of intraocular injections, NAP is difficult to be clinically administered as therapeutic agent in treating retinal diseases. Currently, stable transfection of this octapeptide into cells has not been reported, partly because of its small size and lacking of 5' signal sequence. Here, we have developed a novel NT4-NAP fusion gene by attaching the 5' nonfunctional preproregion of neurotrophin 4 (NT4) to NAP cDNA. Recombinant adeno-associated virus was established to introduce NT4-NAP construct into cultured rat retinal Müller cells (RMC), resulting in sustained high level NAP production from stable transfection. Functional analyses of RMC cells transfected with NAP revealed the remarkably reduced cytotoxicity and apoptosis of the cells under hypoxia. Furthermore, coculturing of transfected RMC-NAP cells with primary rat retinal neural cells offer marked protection to the latter against hypoxia induced cellular damages. Together our data indicate that stable transfection of NAP into retinal Müller cells with constant NAP production is possible. NAP produced from cellular transfection maintained its biological neuroprotective activities. This targeted gene expression may provide an effective treatment for retinal diseases in the near future. PMID:20359852

  4. 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.

  5. 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.

  6. Spectral imaging technique for retinal perfusion detection using confocal scanning laser ophthalmoscopy

    Science.gov (United States)

    Rasta, Seyed Hossein; Manivannan, Ayyakkannu; Sharp, Peter F.

    2012-11-01

    To evaluate retinal perfusion in the human eye, a dual-wavelength confocal scanning laser ophthalmoscope (cSLO) was developed that provides spectral imaging of the fundus using a combination of red (670 nm) and near-infrared (810 nm) wavelengths. The image of the ocular fundus was analyzed to find out if quantitative measurements of the reflectivity of tissue permit assessment of the oxygen perfusion of tissue. We explored problems that affect the reproducibility of patient measurements such as non-uniformity errors on the image. For the first time, an image processing technique was designed and used to minimize the errors of oxygen saturation measurements by illumination correction in retina wide field by increasing SNR. Retinal images were taken from healthy and diabetic retinopathy eyes using the cSLO with a confocal aperture of 100 ?m. The ratio image (RI) of red/IR, as oxygen saturation (SO2) index, was calculated for normal eyes. The image correction technique improved the reproducibility of the measurements. Average RI intensity variation of healthy retina tissue was determined within a range of about 5.5%. The capability of the new technique to discriminate oxygenation levels of retinal artery and vein was successfully demonstrated and showed good promise in the diagnosis of the perfused retina.

  7. Anomalous origin of right coronary artery from pulmonary artery

    OpenAIRE

    Gupta, Rajat; Marwah, Ashutosh; Shrivastva, Savitri

    2012-01-01

    Anomalous origin of coronary artery from the pulmonary artery is a rare anomaly that most frequently involves the left coronary artery and very rarely the right coronary artery. These lesions can be missed on echocardiography unless carefully looked for. We describe a case of isolated anomalous origin of right coronary artery from pulmonary artery diagnosed on echocardiography and confirmed by computed tomography (CT) angiography.

  8. Reproducibility of retinal circulation measurements obtained using laser speckle flowgraphy-NAVI in patients with glaucoma

    Directory of Open Access Journals (Sweden)

    Nakamura M

    2011-08-01

    Full Text Available Naoko Aizawa, Yu Yokoyama, Naoki Chiba, Kazuko Omodaka, Masayuki Yasuda, Takaaki Otomo, Masahiko Nakamura, Nobuo Fuse, Toru NakazawaDepartment of Ophthalmology, Tohoku University Graduate School of Medicine Sendai, Miyagi, JapanBackground: Laser speckle flowgraphy (LSFG enables noninvasive quantification of the retinal circulation in glaucoma patients. In this study, we tested the intrasession reproducibility of LSFG-NAVI, a modified LSFG technique.Methods: Sixty-five eyes from 33 subjects (male (M:female (F = 17:16 with a mean age of 49.4 ± 11.2 years were examined in this study. Two parameters indicating reproducibility – the coefficient of variation (COV and the intraclass correlation coefficient (ICC – were analyzed three times on the same day that mean blur rate (MBR was measured using LSFG-NAVI. The sites analyzed were the retinal artery and vein, the optic disk, and the choroid. Following classification according to the Glaucoma Hemifield Test (GHT; SITA-Standard 30-2 program, the COV and ICC were examined in patients with (GHT+; 38 eyes, M:F = 20:18, average age 48.9 ± 12.8 years and without (GHT-; 27 eyes, M:F = 13:14, average age 50.1 ± 8.7 years abnormal glaucomatous visual fields.Results: For all subjects, the intrasession reproducibility of MBR in the optic disk (COV: 3.4 ± 2.0; ICC: 0.95 and choroid (COV: 4.7 ± 3.4; ICC: 0.98 was excellent. The reproducibility for the retinal vein (COV: 8.4 ± 5.6, ICC: 0.90 and retinal artery (COV: 10.9 ± 9.9, ICC: 0.9 was moderate. MBRs in the optic disk had good reproducibility in both the GHT+ group (COV: 3.8 ± 2.0; ICC: 0.97 and the GHT? group (COV: 2.9 ± 2.1; ICC: 0.95. Local assessment of the optic disk in normal or glaucoma patients showed that the COVs of the quadrant optic disk areas were best in the temporal area of MBR (3.4%, 4.2%, respectively.Conclusion: LSFG-NAVI showed favorable reproducibility in evaluation of retinal circulation of glaucoma patients, particularly in the optic disk and choroid.Keywords: ocular circulation, reproducibility, optic nerve, retina

  9. 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...

  10. Partial rescue of retinal function in chronically hypoglycemic mice

    OpenAIRE

    Umino, Yumiko; Cuenca, Nicolas; Everhart, Drew; Fernandez-Sanchez, Laura; Barlow, Robert B.; Solessio, Eduardo

    2012-01-01

    Purpose. Mice rendered hypoglycemic by a null mutation in the glucagon receptor gene Gcgr display late-onset retinal degeneration and loss of retinal sensitivity. Acute hyperglycemia induced by dextrose ingestion does not restore their retinal function, which is consistent with irreversible loss of vision. The goal of this study was to establish whether long-term administration of high dietary glucose rescues retinal function and circuit connectivity in aged Gcgr?/? mice. Methods. Gcgr?/? mic...

  11. Optimal management of cytomegalovirus retinitis in patients with AIDS

    OpenAIRE

    Michael W Stewart

    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. Ocular Tuberculosis Initially Presenting as Central Retinal Vein Occlusion

    OpenAIRE

    Mahyudin, Muiz; Choo, May May; Ramli, Norlina Mohd; Omar, Sharifah S.

    2010-01-01

    A 23-year-old man presented with central retinal vein occlusion. The retinal haemorrhages worsened and signs of retinal vasculitis appeared later as vision dropped from 6/60 to Counting Fingers. No signs of systemic disease were observed. Routine Mantoux test and chest radiograph were negative for tuberculosis. Fundus flourescein angiogram confirmed presence of retinal vasculitis. Both systemic and topical corticosteroid therapy were ineffective. Polymerase chain reaction analysis of vitreous...

  13. Promises of stem cell therapy for retinal degenerative diseases

    OpenAIRE

    Wong, Ian Yat-hin; Poon, Ming-wai; Pang, Rosita Tsz-wai; Lian, Qizhou; Wong, David

    2011-01-01

    With the development of stem cell technology, stem cell-based therapy for retinal degeneration has been proposed to restore the visual function. Many animal studies and some clinical trials have shown encouraging results of stem cell-based therapy in retinal degenerative diseases. While stem cell-based therapy is a promising strategy to replace damaged retinal cells and ultimately cure retinal degeneration, there are several important challenges which need to be overcome before stem cell tech...

  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. 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. 

  16. Carotid artery surgery

    Science.gov (United States)

    Carotid endarterectomy; CAS surgery; Carotid artery stenosis - surgery; Endarterectomy - carotid artery ... During carotid endarterectomy: You receive general anesthesia . You are asleep and pain-free. Some hospitals use local anesthesia instead. Only ...

  17. Peripheral Artery Disease

    Science.gov (United States)

    ... In P.A.D., the arteries that carry oxygenated blood throughout the body become narrowed or even ... artery. Catheter-directed Thrombolysis : In this minimally invasive treatment, an interventional radiologist uses a catheter to reach ...

  18. Radial Artery Catheterization

    Science.gov (United States)

    ... by Shah, P. B. Related Content Load related Internet Resources information Social ... of Radial Artery Catheterization The Radial Artery Catheterization Procedure Risks of Radial Catheterization Deciding Between the Radial and ...

  19. Coronary Artery Disease

    Science.gov (United States)

    Coronary artery disease (CAD) is the most common type of heart disease. It is the leading cause of death ... both men and women. CAD happens when the arteries that supply blood to heart muscle become hardened ...

  20. Coronary Artery Bypass

    Science.gov (United States)

    ... procedures performed each year in the United States. Arteries can become clogged over time by the buildup ... bypass" around a section of clogged or diseased artery. The surgery involves using a section of blood ...

  1. Optical coherence tomography changes in macular CMV retinitis

    OpenAIRE

    Sun, Lisa L.; Goodwin, Todd; Park, Joseph J.

    2012-01-01

    Cytomegalovirus (CMV) retinitis characteristically causes peripheral retinitis with associated vasculitis. It rarely begins in the macula or causes macular necrosis exclusively. We report a case of unilateral macular CMV retinitis in a 65-year-old immunosuppressed patient and document changes in the macula during treatment through optical coherence tomography (OCT).

  2. Acute Arterial Emergencies

    OpenAIRE

    Dagnone, L. E.; Brown, P. M.

    1983-01-01

    The response of the primary care physician in the initial assessment and management of acute arterial injuries will often be the deciding factor in survival of life, limb or organ system. Most arterial emergencies occur as a result of trauma, disruption of vessel wall and/or occlusion of flow. The common clinical syndromes of acute arterial emergencies are injuries to and beyond the aorta, acute aortic dissection, ruptured aortic aneurysm, and thromboembolic occlusive arterial disease. The ro...

  3. Risk factors for central and branch retinal vein occlusion: a meta-analysis of published clinical data.

    Science.gov (United States)

    Kolar, Petr

    2014-01-01

    Retinal vein occlusion (RVO) is a major cause of vision loss. Of the two main types of RVO, branch retinal vein occlusion (BRVO) is 4 to 6 times more prevalent than central retinal vein occlusion (CRVO). A basic risk factor for RVO is advancing age. Further risk factors include systemic conditions like hypertension, arteriosclerosis, diabetes mellitus, hyperlipidemia, vascular cerebral stroke, blood hyperviscosity, and thrombophilia. A strong risk factor for RVO is the metabolic syndrome (hypertension, diabetes mellitus, and hyperlipidemia). Individuals with end-organ damage caused by diabetes mellitus and hypertension have greatly increased risk for RVO. Socioeconomic status seems to be a risk factor too. American blacks are more often diagnosed with RVO than non-Hispanic whites. Females are, according to some studies, at lower risk than men. The role of thrombophilic risk factors in RVO is still controversial. Congenital thrombophilic diseases like factor V Leiden mutation, hyperhomocysteinemia and anticardiolipin antibodies increase the risk of RVO. Cigarette smoking also increases the risk of RVO as do systemic inflammatory conditions like vasculitis and Behcet disease. Ophthalmic risk factors for RVO are ocular hypertension and glaucoma, higher ocular perfusion pressure, and changes in the retinal arteries. PMID:25009743

  4. Nuclear Factor of Activated T Cells Is Activated in the Endothelium of Retinal Microvessels in Diabetic Mice

    Science.gov (United States)

    Zetterqvist, Anna V.; Blanco, Fabiana; Öhman, Jenny; Kotova, Olga; Berglund, Lisa M.; de Frutos Garcia, Sergio; Al-Naemi, Raed; Wigren, Maria; McGuire, Paul G.; Gonzalez Bosc, Laura V.; Gomez, Maria F.

    2015-01-01

    The pathogenesis of diabetic retinopathy (DR) remains unclear but hyperglycemia is an established risk factor. Endothelial dysfunction and changes in Ca2+ signaling have been shown to precede the onset of DR. We recently demonstrated that high extracellular glucose activates the Ca2+/calcineurin-dependent transcription factor NFAT in cerebral arteries and aorta, promoting the expression of inflammatory markers. Here we show, using confocal immunofluorescence, that NFAT is expressed in the endothelium of retinal microvessels and is readily activated by high glucose. This was inhibited by the NFAT blocker A-285222 as well as by the ectonucleotidase apyrase, suggesting a mechanism involving the release of extracellular nucleotides. Acute hyperglycemia induced by an IP-GTT (intraperitoneal glucose tolerance test) resulted in increased NFATc3 nuclear accumulation and NFAT-dependent transcriptional activity in retinal vessels of NFAT-luciferase reporter mice. In both Akita (Ins2+/?) and streptozotocin- (STZ-) induced diabetic mice, NFAT transcriptional activity was elevated in retinal vessels. In vivo inhibition of NFAT with A-285222 decreased the expression of OPN and ICAM-1 mRNA in retinal vessels, prevented a diabetes driven downregulation of anti-inflammatory IL-10 in retina, and abrogated the increased vascular permeability observed in diabetic mice. Results identify NFAT signaling as a putative target for treatment of microvascular complications in diabetes. PMID:25918731

  5. 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.

  6. Automated retinal layer segmentation and characterization

    Science.gov (United States)

    Luisi, Jonathan; Briley, David; Boretsky, Adam; Motamedi, Massoud

    2014-05-01

    Spectral Domain Optical Coherence Tomography (SD-OCT) is a valuable diagnostic tool in both clinical and research settings. The depth-resolved intensity profiles generated by light backscattered from discrete layers of the retina provide a non-invasive method of investigating progressive diseases and injury within the eye. This study demonstrates the application of steerable convolution filters capable of automatically separating gradient orientations to identify edges and delineate tissue boundaries. The edge maps were recombined to measure thickness of individual retinal layers. This technique was successfully applied to longitudinally monitor changes in retinal morphology in a mouse model of laser-induced choroidal neovascularization (CNV) and human data from age-related macular degeneration patients. The steerable filters allow for direct segmentation of noisy images, while novel recombination of weaker segmentations allow for denoising post-segmentation. The segmentation before denoising strategy allows the rapid detection of thin retinal layers even under suboptimal imaging conditions.

  7. 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...

  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. Novel Fluorescein Angiography-Based Computer-Aided Algorithm for Assessment of Retinal Vessel Permeability

    Science.gov (United States)

    Chassidim, Yoash; Parmet, Yisrael; Tomkins, Oren; Knyazer, Boris; Friedman, Alon; Levy, Jaime

    2013-01-01

    Purpose To present a novel method for quantitative assessment of retinal vessel permeability using a fluorescein angiography-based computer algorithm. Methods Twenty-one subjects (13 with diabetic retinopathy, 8 healthy volunteers) underwent fluorescein angiography (FA). Image pre-processing included removal of non-retinal and noisy images and registration to achieve spatial and temporal pixel-based analysis. Permeability was assessed for each pixel by computing intensity kinetics normalized to arterial values. A linear curve was fitted and the slope value was assigned, color-coded and displayed. The initial FA studies and the computed permeability maps were interpreted in a masked and randomized manner by three experienced ophthalmologists for statistical validation of diagnosis accuracy and efficacy. Results Permeability maps were successfully generated for all subjects. For healthy volunteers permeability values showed a normal distribution with a comparable range between subjects. Based on the mean cumulative histogram for the healthy population a threshold (99.5%) for pathological permeability was determined. Clear differences were found between patients and healthy subjects in the number and spatial distribution of pixels with pathological vascular leakage. The computed maps improved the discrimination between patients and healthy subjects, achieved sensitivity and specificity of 0.974 and 0.833 respectively, and significantly improved the consensus among raters for the localization of pathological regions. Conclusion The new algorithm allows quantification of retinal vessel permeability and provides objective, more sensitive and accurate evaluation than the present subjective clinical diagnosis. Future studies with a larger patients’ cohort and different retinal pathologies are awaited to further validate this new approach and its role in diagnosis and treatment follow-up. Successful evaluation of vasculature permeability may be used for the early diagnosis of brain microvascular pathology and potentially predict associated neurological sequelae. Finally, the algorithm could be implemented for intraoperative evaluation of micovascular integrity in other organs or during animal experiments. PMID:23626701

  11. Reading visual braille with a retinal prosthesis.

    Science.gov (United States)

    Lauritzen, Thomas Z; Harris, Jordan; Mohand-Said, Saddek; Sahel, Jose A; Dorn, Jessy D; McClure, Kelly; Greenberg, Robert J

    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 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?×?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?×?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. PMID:23189036

  12. 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.

  13. 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.

  14. Presumed glial retinal hamartomas in Usher's syndrome.

    Science.gov (United States)

    Awan, K J

    1976-07-01

    The presence of glial hamartomas of the retina and the optic disc in retinitis pigmentosa is discussed. This association is described in a 26 year old white male with Usher's syndrome who had at the posterior pole of each eye a mass which closely resembled the mulberry-like lesions of tuberose sclerosis. Several fine blood vessels were seen on the surface of these masses. The significance of the association of these presumed hamartomas with retinitis pigmentosa is not clear. They might be the result of a focal reactive hyperplasia of the glial cells of the retina. PMID:949638

  15. Proliferative diabetic retinopathy in typical retinitis pigmentosa.

    Science.gov (United States)

    Preethi, Srinivasaraghavan; Rajalakshmi, Adithyapuram Ramachandran

    2015-01-01

    A 39-year-old woman with typical retinitis pigmentosa (RP) for 9?years and a positive family history of night blindness was diagnosed with diabetes mellitus (DM). She developed proliferative diabetic retinopathy (PDR) during the course of disease. She was promptly managed with pan retinal photocoagulation (PRP). PDR developing in a case of typical RP is extremely rare and has not been reported in the literature to date. Recognition of this rare, vision threatening complication, points out a definite need to further look deep into the pathogenesis of diabetic retinopathy. PMID:26021380

  16. 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).

  17. 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.

  18. 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.

  19. Retinitis pigmentosa and congenital toxoplasmosis: A rare coexistence

    Directory of Open Access Journals (Sweden)

    Chhabra Manpreet

    2007-01-01

    Full Text Available 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 electroretinograph, a diagnosis of retinitis pigmentosa with congenital toxoplasmosis was made. Retinitis pigmentosa may co-exist with congenital toxoplasmosis that may affect the patient?s overall ocular morbidity and visual acuity.

  20. 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.

  1. The retinal pigment epithelium: an important player of retinal disorders and regeneration.

    Science.gov (United States)

    Chiba, Chikafumi

    2014-06-01

    The retinal pigment epithelium (RPE) is a partner of the neural retina and is indispensable for vision. In humans, proliferation and transformation (cell-type switching) of RPE cells after a traumatic injury of the neural retina causes a retinal disorder leading to loss of vision. In contrast, in certain adult amphibians such as Xenopus laevis and the newt, a similar process in RPE cells leads to regeneration of the entire retina. In this review, on the basis of accumulating evidence in basic biology and medical sciences, similarities and differences between these RPE-mediated retinal disorders and regeneration in adult vertebrates are highlighted, providing a connection to future research that should be designed to establish clues for the treatment of pathogenesis caused by RPE while promoting RPE-mediated retinal regeneration in a patient's eyes. PMID:23880527

  2. 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

  3. 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

  4. Vildagliptin in addition to metformin improves retinal blood flow and erythrocyte deformability in patients with type 2 diabetes mellitus - results from an exploratory study.

    Science.gov (United States)

    Berndt-Zipfel, Christine; Michelson, Georg; Dworak, Markus; Mitry, Michael; Löffler, Andrea; Pfützner, Andreas; Forst, Thomas

    2013-01-01

    Numerous rheological and microvascular alterations characterize the vascular pathology in patients with type 2 diabetes mellitus (T2DM). This study investigated effects of vildagliptin in comparison to glimepiride on retinal microvascular blood flow and erythrocyte deformability in T2DM.Fourty-four patients with T2DM on metformin monotherapy were included in this randomized, exploratory study over 24 weeks. Patients were randomized to receive either vildagliptin (50 mg twice daily) or glimepiride individually titrated up to 4 mg in addition to ongoing metformin treatment. Retinal microvascular blood flow (RBF)and the arteriolar wall to lumen ratio (WLR) were assessed using a laser doppler scanner. In addition, the rythrocyte elongation index (EI) was measured at different shear stresses using laserdiffractoscopy.Both treatments improved glycaemic control (p glimepiride, vildagliptin significantly increased retinal bloodflow and decreased the arterial WLR (p < 0.05 vs. baseline respectively). The EI increased during both treatments over a wide range of applied shear stresses (p < 0.05 vs. baseline). An inverse correlation could be observed between improved glycaemic control (HbA1c) and EI (r = -0.524; p < 0.0001) but not with the changes in retinal microvascular measurements.Our results suggest that vildagliptin might exert beneficial effects on retinal microvascular blood flow beyond glucose control. In contrast, the improvement in erythrocyte deformability observed in both treatment groups,seems to be a correlate of improved glycaemic control. PMID:23565740

  5. Automated segmentation of outer retinal layers in macular OCT images of patients with retinitis pigmentosa

    OpenAIRE

    Yang, Qi; Reisman, Charles A.; Chan, Kinpui; Ramachandran, Rithambara; Raza, Ali; Hood, Donald C.

    2011-01-01

    To provide a tool for quantifying the effects of retinitis pigmentosa (RP) seen on spectral domain optical coherence tomography images, an automated layer segmentation algorithm was developed. This algorithm, based on dual-gradient information and a shortest path search strategy, delineates the inner limiting membrane and three outer retinal boundaries in optical coherence tomography images from RP patients. In addition, an automated inner segment (IS)/outer segment (OS) contour detection met...

  6. Temporary Exudative Retinal Detachment following Photodynamic Therapy in a Patient with Retinal Capillary Hemangioblastoma

    OpenAIRE

    Selver, Ozlem Barut; Yaman, Aylin; Saatci, Ali Osman

    2011-01-01

    A 21-year-old male with von Hippel-Lindau syndrome was treated for a retinal hemangioblastoma with photodynamic therapy (PDT). We employed the standard PDT protocol with doubled treatment duration. Seven days after the procedure, there were some perilesional intra- and subretinal hemorrhages and significant exudative retinal detachment extending inferiorly. Four weeks later, the hemorrhages had mostly cleared, and diminished subretinal fluid and partial regression of the hemangioblastoma were...

  7. Histopathological findings after retinal endovascular lysis in central retinal vein occlusion

    OpenAIRE

    Feltgen, Nicolas; Agostini, Hansjuergen; Auw-haedrich, Claudia; Hansen, Lutz L.

    2009-01-01

    This case study explores the histopathological findings 9 months after retinal endovascular lysis (REVL) in a 62-year-old woman having a 7-week-old, highly ischaemic central retinal vein occlusion (CRVO) with hand movement vision. Angiographic examination 3 days postoperatively did not show improved arteriovenous passage time. In addition, the patient’s postoperative vision did not change, and despite intensive photocoagulation and cryotherapy in the early postoperative period, the globe ha...

  8. Central Retinal Vein Occlusion in a Patient with Retinal Vasculitis and Crohn's Disease

    OpenAIRE

    Figueiredo, Lígia; Rothwell, Renata; Brandão, Arnaldo; Fonseca, Sofia

    2014-01-01

    The authors report a rare case of a 47-year-old woman with Crohn's disease (CD) who presented with retinal vasculitis and central retinal vein occlusion (CRVO) during remission. The patient complained of sudden painless visual loss in her left eye (OS). Ophthalmologic evaluation revealed a best corrected visual acuity (BCVA) of 20/20 in the right eye and hand movements in OS. Ophthalmoscopy and fluorescein angiography of OS showed signs of nonischemic CRVO and extensive vasculitis. She was tr...

  9. 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.

  10. A Novel In Vitro Sensing Configuration for Retinal Physiology Analysis of a Sub-Retinal Prosthesis

    Directory of Open Access Journals (Sweden)

    Kyung Hwan Kim

    2012-03-01

    Full Text Available This paper presents a novel sensing configuration for retinal physiology analysis, using two microelectrode arrays (MEAs. In order to investigate an optimized stimulation protocol for a sub-retinal prosthesis, retinal photoreceptor cells are stimulated, and the response of retinal ganglion cells is recorded in an in vitro environment. For photoreceptor cell stimulation, a polyimide-substrate MEA is developed, using the microelectromechanical systems (MEMS technology. For ganglion cell response recording, a conventional glass-substrate MEA is utilized. This new sensing configuration is used to record the response of retinal ganglion cells with respect to three different stimulation methods (monopolar, bipolar, and dual-monopolar stimulation methods. Results show that the geometrical relation between the stimulation microelectrode locations and the response locations seems very low. The threshold charges of the bipolar stimulation and the monopolar stimulation are in the range of 10~20 nC. The threshold charge of the dual-monopolar stimulation is not obvious. These results provide useful guidelines for developing a sub-retinal prosthesis.

  11. 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. 

  12. 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…

  13. Dynamic eye phantom for retinal oximetry measurements

    Science.gov (United States)

    Lemaillet, Paul; Ramella-Roman, Jessica C.

    2009-11-01

    Measurements of oxygen saturation and flow in the retina can yield information about eye health and the onset of eye pathologies such as diabetic retinopathy. Recently, we developed a multiaperture camera that uses the division of the retinal image into several wavelength-sensitive subimages to compute retinal oxygen saturation. The calibration of such instruments is particularly difficult due to the layered structure of the eye and the lack of alternative measurement techniques. For this purpose, we realize an in vitro model of the human eye composed of a lens, the retina vessel, and three layers: the choroid, the retinal pigmented epithelium, and the sclera. The retinal vessel is modeled with a microtube connected to a micropump and a hemoglobin reservoir in a closed circulatory system. Hemoglobin oxygenation in the vessel could be altered using a reversible fuel cell. The sclera is represented by a Spectralon slab. The optical properties of the other layers are mimicked using titanium dioxide as a scatterer, ink as an absorber, and epoxy as a supporting structure. The optical thickness of each layer of the eye phantom is matched to each respective eye layer.

  14. Axial Length in Retinal Vein Occlusion

    Directory of Open Access Journals (Sweden)

    MirNaghi Mousavi

    2015-01-01

    Materials and Methods: After ethical approval, this case-control study was designed in Mashhad University of medical sciences. We selected 63 patients with retinal vein occlusion and 23 control group. Axial length was measured by a mode scan (NIDEK-US 4000, Japan, macular thickness (macular edema was evaluated by Optical Coherence Tomography (ZEISS, Germany. Data were analyzed with SPSS Version 16. P

  15. Stem cell therapy for retinal diseases

    Science.gov (United States)

    Garcia, José Mauricio; Mendonça, Luisa; Brant, Rodrigo; Abud, Murilo; Regatieri, Caio; Diniz, Bruno

    2015-01-01

    In this review, we discuss about current knowledge about stem cell (SC) therapy in the treatment of retinal degeneration. Both human embryonic stem cell and induced pluripotent stem cell has been growth in culture for a long time, and started to be explored in the treatment of blinding conditions. The Food and Drug Administration, recently, has granted clinical trials using SC retinal therapy to treat complex disorders, as Stargardt’s dystrophy, and patients with geographic atrophy, providing good outcomes. This study’s intent is to overview the critical regeneration of the subretinal anatomy through retinal pigment epithelium transplantation, with the goal of reestablish important pathways from the retina to the occipital cortex of the brain, as well as the differentiation from pluripotent quiescent SC to adult retina, and its relationship with a primary retinal injury, different techniques of transplantation, management of immune rejection and tumorigenicity, its potential application in improving patients’ vision, and, finally, approaching future directions and challenges for the treatment of several conditions. PMID:25621115

  16. a Review of Retinal Prosthesis Approaches

    Science.gov (United States)

    Kien, Tran Trung; Maul, Tomas; Bargiela, Andrzej

    Age-related macular degeneration and retinitis pigmentosa are two of the most common diseases that cause degeneration in the outer retina, which can lead to several visual impairments up to blindness. Vision restoration is an important goal for which several different research approaches are currently being pursued. We are concerned with restoration via retinal prosthetic devices. Prostheses can be implemented intraocularly and extraocularly, which leads to different categories of devices. Cortical Prostheses and Optic Nerve Prostheses are examples of extraocular solutions while Epiretinal Prostheses and Subretinal Prostheses are examples of intraocular solutions. Some of the prostheses that are successfully implanted and tested in animals as well as humans can restore basic visual functions but still have limitations. This paper will give an overview of the current state of art of Retinal Prostheses and compare the advantages and limitations of each type. The purpose of this review is thus to summarize the current technologies and approaches used in developing Retinal Prostheses and therefore to lay a foundation for future designs and research directions.

  17. Dye-Free Porcine Model of Experimental Branch Retinal Vein Occlusion : A Suitable Approach for Retinal Proteomics

    DEFF Research Database (Denmark)

    JØrgensen Cehofski, Lasse; Kruse, Anders

    2015-01-01

    Branch retinal vein occlusion induces complex biological processes in the retina that are generated by a multitude of interacting proteins. These proteins and their posttranslational modifications can effectively be studied using modern proteomic techniques. However, no method for studying large-scale protein changes following branch retinal vein occlusion has been available until now. Obtainment of retinal tissue exposed to branch retinal vein occlusion is only available through experimental animal models. Traditional models of experimental branch retinal vein occlusion require the use of Rose Bengal dye combined with argon laser photocoagulation. The use of Rose Bengal dye is problematic in proteomic studies as the dye can induce multiple protein modifications when irradiated. This paper presents a novel technique for proteomic analysis of porcine retinal tissue with branch retinal vein occlusion combining a dye-free experimental model with label-free liquid chromatography mass spectrometry based proteomics.

  18. Transposition of Anterior Choroidal Artery and Posterior Communicating Artery Origin

    OpenAIRE

    Choi, Chan Young; Lee, Chae Heuck

    2012-01-01

    The anterior choroidal artery has several kinds of variations. Among them, the transposition of anterior choroidal artery and posterior communicating artery origins has been extremely rare. We report a case with cerebral aneurysm arising from posterior communicating artery which origin was distal to the anterior choroidal artery and review the relevant literature.

  19. Unilateral Double Axillary and Double Brachial Arteries: Embryological Basis and Clinical Implications Arterias Axilar y Braquial Dobles Unilaterales: Bases Embriológicas e Implicaciones Clínicas

    Directory of Open Access Journals (Sweden)

    S Jayakumari

    2006-09-01

    Full Text Available This report presents double axillary and double brachial arteries on the right side of an adult male cadaver. In this case, the right axillary artery bifurcated into axillary artery I and axillary artery II posterior to the pectoralis minor muscle. Both the axillary arteries with their branches traversed upto lower border of teres major muscle and continued further as seperate entities into the cubital fossa as brachial artery I and brachial artery II respectively. The axillary artery I which continued as brachial artery I was superficial and tortuous in its course, while the axillary artery II was slender and deeply situated. The thoraco-acromial, lateral thoracic and subscapular arteries took origin from axillary artery I. The superior thoracic artery was seen arising from the thoraco-acromial artery. The anterior and posterior circumflex humeral arteries arose from axillary artery II.The profunda brachii artery was given off by the brachial artery II, while at the level of intercondylar line, the ulnar artery was given off by brachial artery I. In the cubital fossa, the brachial artery divided into radial and common interosseous artery, while the brachial artery II ended by anastomosis with brachial artery I. The ulnar, radial and common interosseous arteries continued as separate entities and exhibited a normal course and distribution in the forearm.The hypothesis for the embryological basis of persistence of double axillary and double brachical arteries may be useful for experimental embryology. The knowledge of such multiple arterial variations as in the present case is of immense significance during Doppler scanning of blood vessels for clinical diagnosis and surgical management of diseases of superior extremityEste reporte describe la presencia de las arterias axilar y braquial duplicadas en el lado derecho de un cadáver adulto de sexo masculino. La arteria axilar derecha se bifurcó en arterias axilares I y II, localizadas posteriormente al músculo pectoral menor. Ambas arterias, con sus respectivas ramas atravesaron bajo el músculo redondo mayor y continuaron como arterias braquiales I y II, respectivamente. La arteria axilar I, que se continuó como arteria braquial I, tuvo un trayecto superficial y tortuoso, mientras que la arteria axilar II fue de poco calibre y de localización profunda. Las arterias toracoacromial, torácica lateral y subescapular se originaron de la arteria axilar I. La arteria torácica superior se originó de la arteria toracoacromial. Las arterias circunflejas humerales anterior y posterior se originaron desde la arteria axilar II. La arteria braquial profundase originó de la arteria braquial II, mientras que a nivel de la línea intercondílea, la arteria ulnar se originó de la arteria braquial I. En la fosa cubital, la arteria braquial I se dividió en arterias radial e interósea común, mientras que la arteria braquial II terminó anastomosándose con la arteria braquial I. Las arterias ulnar, radial e interóseas común continuaron como arterias independientes y tuvieron un trayecto y distribución normales en el antebrazo. La persistencia de arterias axilar y braquial dobles tiene una base embriológica, pudiendo ser de interés para la embriología experimental. El conocimiento de estas variaciones arteriales múltiples, como el presente caso, es de importancia fundamental durante la medición de flujo en los vasos sanguíneos a través de Doppler, para el diagnóstico clínico y manejo quirúrgico de enfermedades que afectan al miembro superior

  20. Unilateral Double Axillary and Double Brachial Arteries: Embryological Basis and Clinical Implications / Arterias Axilar y Braquial Dobles Unilaterales: Bases Embriológicas e Implicaciones Clínicas

    Scientific Electronic Library Online (English)

    S, Jayakumari; Gayatri, Rath; Jyoti, Arora.

    2006-09-01

    Full Text Available Este reporte describe la presencia de las arterias axilar y braquial duplicadas en el lado derecho de un cadáver adulto de sexo masculino. La arteria axilar derecha se bifurcó en arterias axilares I y II, localizadas posteriormente al músculo pectoral menor. Ambas arterias, con sus respectivas ramas [...] atravesaron bajo el músculo redondo mayor y continuaron como arterias braquiales I y II, respectivamente. La arteria axilar I, que se continuó como arteria braquial I, tuvo un trayecto superficial y tortuoso, mientras que la arteria axilar II fue de poco calibre y de localización profunda. Las arterias toracoacromial, torácica lateral y subescapular se originaron de la arteria axilar I. La arteria torácica superior se originó de la arteria toracoacromial. Las arterias circunflejas humerales anterior y posterior se originaron desde la arteria axilar II. La arteria braquial profundase originó de la arteria braquial II, mientras que a nivel de la línea intercondílea, la arteria ulnar se originó de la arteria braquial I. En la fosa cubital, la arteria braquial I se dividió en arterias radial e interósea común, mientras que la arteria braquial II terminó anastomosándose con la arteria braquial I. Las arterias ulnar, radial e interóseas común continuaron como arterias independientes y tuvieron un trayecto y distribución normales en el antebrazo. La persistencia de arterias axilar y braquial dobles tiene una base embriológica, pudiendo ser de interés para la embriología experimental. El conocimiento de estas variaciones arteriales múltiples, como el presente caso, es de importancia fundamental durante la medición de flujo en los vasos sanguíneos a través de Doppler, para el diagnóstico clínico y manejo quirúrgico de enfermedades que afectan al miembro superior Abstract in english This report presents double axillary and double brachial arteries on the right side of an adult male cadaver. In this case, the right axillary artery bifurcated into axillary artery I and axillary artery II posterior to the pectoralis minor muscle. Both the axillary arteries with their branches trav [...] ersed upto lower border of teres major muscle and continued further as seperate entities into the cubital fossa as brachial artery I and brachial artery II respectively. The axillary artery I which continued as brachial artery I was superficial and tortuous in its course, while the axillary artery II was slender and deeply situated. The thoraco-acromial, lateral thoracic and subscapular arteries took origin from axillary artery I. The superior thoracic artery was seen arising from the thoraco-acromial artery. The anterior and posterior circumflex humeral arteries arose from axillary artery II.The profunda brachii artery was given off by the brachial artery II, while at the level of intercondylar line, the ulnar artery was given off by brachial artery I. In the cubital fossa, the brachial artery divided into radial and common interosseous artery, while the brachial artery II ended by anastomosis with brachial artery I. The ulnar, radial and common interosseous arteries continued as separate entities and exhibited a normal course and distribution in the forearm.The hypothesis for the embryological basis of persistence of double axillary and double brachical arteries may be useful for experimental embryology. The knowledge of such multiple arterial variations as in the present case is of immense significance during Doppler scanning of blood vessels for clinical diagnosis and surgical management of diseases of superior extremity

  1. About Peripheral Artery Disease (PAD)

    Science.gov (United States)

    About Peripheral Artery Disease (PAD) Updated:Sep 15,2014 Peripheral artery disease (PAD) is a narrowing of the peripheral arteries to ... was last reviewed on 8/05/2014. Peripheral Artery Disease • Home • About Peripheral Artery Disease (PAD) • Why ...

  2. N -methyl- N -nitrosourea-induced retinal degeneration in mice.

    Science.gov (United States)

    Chen, Yuan-Yuan; Liu, Shi-Liang; Hu, Dan-Ping; Xing, Yi-Qiao; Shen, Yin

    2014-04-01

    Mouse retinal degeneration models have been investigated for many years in the hope of understanding the mechanism of photoreceptor cell death. N -methyl- N -nitrosourea (MNU) has been previously shown to induce outer retinal degeneration in mice. After MNU was intraperitoneally injected in C57/BL mice, we observed a gradual decrease in the outer nuclear layer (ONL) thickness associated with photoreceptor outer segment loss, bipolar cell dendritic retraction and reactive gliosis. Reactive gliosis was confirmed by increased GFAP protein levels. More serious damage to the central retina as opposed to the peripheral retina was found in the MNU-induced retinal degeneration model. Retinal ganglion cells (RGC) appear to be spared for at least two months after MNU treatment. Following retinal vessel labelling, we observed vascular complexes in the distal vessels, indicating retinal vessel damage. In the remnant retinal photoreceptor of the MNU-treated mouse, concentrated colouring nuclei were detected by electron microscopy, together with the loss of mitochondria and displaced remnant synaptic ribbons in the photoreceptor. We also observed decreased mitochondrial protein levels and increased amounts of nitrosylation/nitration in the photoreceptors. The mechanism of MNU-induced apoptosis may result from oxidative stress or the loss of retinal blood supply. MNU-induced mouse retinal degeneration in the outer retina is a useful animal model for photoreceptor degeneration diseases, such as age-related macular degeneration (AMD) and retinitis pigmentosa (RP). PMID:24509257

  3. 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.

  4. Prophylactic treatment of retinal breaks - a systematic review

    DEFF Research Database (Denmark)

    Blindbaek, SØren; 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.

  5. 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 (<5%) on the critical 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

  6. Hepatic Artery Infusion Chemotherapy

    OpenAIRE

    Tuchmann, A.; Schu?ller, 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 w...

  7. Celiac Artery Compression Syndrome

    OpenAIRE

    Mohammed Muqeetadnan; Syed Amer; Ambreen Rahman; Salman Nusrat; Syed Hassan

    2013-01-01

    Celiac artery compression syndrome is a rare disorder characterized by episodic abdominal pain and weight loss. It is the result of external compression of celiac artery by the median arcuate ligament. We present a case of celiac artery compression syndrome in a 57-year-old male with severe postprandial abdominal pain and 30-pound weight loss. The patient eventually responded well to surgical division of the median arcuate ligament by laparoscopy.

  8. 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.

  9. Study of the variations of superior cerebellar artery in human cadavers

    Directory of Open Access Journals (Sweden)

    Padmavathi G

    2014-04-01

    Methods: 150 SCAs were studied by gross dissection of 75 formalin embalmed brains obtained from the department of anatomy Mysore medical college and MVJ medical college over a period of 5 years. Results: Variations like duplication in the origin was seen in 23.3%, triplication in 2% of SCAs, and abnormal origin from Posterior Cerebellar Artery (PCA in 25.3% were noted. Other variations like tortuous course and fenestration of SCA were found. The distance from the origin of SCA to PCA ranged between 0.7-4.5 mm. The length from SCA origin to its bifurcation ranged from 6-23 mm. Outer diameter of SCA trunk at its origin varied from 1.2-2.8 mm. The outer diameter of the Basilar Artery (BA at the basilar apex ranged between 3.2-6 mm. Conclusion: The presence of variations can alter the plan of surgical and radiological procedures. The knowledge of such variations and anomalies along with potential clinical manifestations is of paramount importance primarily for neurosurgeons and neuroradiologists. [Int J Res Med Sci 2014; 2(2.000: 699-703

  10. Variable involvement of the perivascular retinal tissue in carbonic anhydrase inhibitor induced relaxation of porcine retinal arterioles in vitro.

    DEFF Research Database (Denmark)

    Kehler, Anne Katrine; Holmgaard, Kim

    2007-01-01

    PURPOSE: Inhibition of carbonic anhydrase in the eye is an important treatment modality for reducing the intraocular pressure in glaucoma. However, evidence suggests that carbonic anhydrase inhibition also exerts a relaxing effect on the vessels in the optic nerve, and it has been suggested that this vasorelaxing effect is a result of an interplay between the perivascular tissue and constituents in the retinal vascular wall. However, the exact nature of this interplay is unknown. METHODS: Isolated porcine retinal arterioles and arterioles with preserved perivascular retinal tissue were mounted in a myograph. After precontraction with the prostaglandin analogue U46619, the vasorelaxing effect of the carbonic anhydrase inhibitors methyl bromopyruvate, ethyl bromopyruvate, acetazolamide, and dorzolamide were studied. RESULTS: All the examined carbonic anhydrase inhibitors induced a significant relaxation of retinal arterioles. There was no significant difference between the effect of the different carbonic anhydrase inhibitors in the presence of perivascular retinal tissue. However, in the isolated retinal arterioles the vasodilating effect of dorzolamide was significantly lower, and the vasodilating effect of acetazolamide almost disappeared. CONCLUSIONS: A further elucidation of the mechanisms of action of carbonic anhydrase-induced dilation of retinal arterioles may contribute to a better understanding of the regulation of retinal blood flow. The perivascular retinal tissue may play a significant role in diameter control of retinal arterioles. Udgivelsesdato: 2007-Oct

  11. Retinal angiographic blood flowmetry is reduced in the ocular ischaemic syndrome

    DEFF Research Database (Denmark)

    Hansen, Grith Lssrkholm; Kofoed, Peter Kristian

    2013-01-01

    INTRODUCTION: The aim of this study was to examine the use of quantitative fluorescein angiographic analysis as a means of estimating rates of perfusion of the retina in eyes with a circulatory deficit secondary to carotid artery stenosis. MATERIAL AND METHODS: The study included 21 eyes with ocular ischaemic syndrome (OIS) and 20 control eyes from subjects with carotid artery stenosis but without signs of ocular ischaemia. Analyses of video fluorescein angiograms extracting time intervals for the time delay between specific phases of the angiogram were performed. Time delay was compared between groups and in relation to degree of carotid artery stenosis and ocular systolic blood pressure. RESULTS: Among the three flow indices of retinal perfusion (arteriovenous passage time 1 (AVP1), arteriovenous passage time 2 (AVP2) and venous filling time (VP)), those including the venous filling phase were significantly prolonged in the OIS group. Furthermore, AVP2 was delayed by 3 sec. in OIS eyes (16.6 sec. versus 13.6 sec. in controls). VP was 2.4 sec. longer in OIS eyes (11.5 sec. versus 9.1 sec.). We found a significant correlation between AVP2 and ocular perfusion pressure, but no correlation between the degree of carotid artery stenosis and any of the flow indices. CONCLUSION: In a patient population spanning a wide ocular systolic blood pressure range, angiography-based quantitative flowmetry demonstrated a difference between carotid artery stenosis patients with and without OIS and a correlation between flow and ocular perfusion pressure. While angiographic flowmetry proved effective in discriminating between groups of individuals, it can only be used to support the diagnosis of the ocular ischaemic syndrome in patients with extreme flow reduction.

  12. Investigation of retinal morphology alterations using spectral domain optical coherence tomography in a mouse model of retinal branch and central retinal vein occlusion.

    Science.gov (United States)

    Ebneter, Andreas; Agca, Cavit; Dysli, Chantal; Zinkernagel, Martin S

    2015-01-01

    Retinal vein occlusion is a leading cause of visual impairment. Experimental models of this condition based on laser photocoagulation of retinal veins have been described and extensively exploited in mammals and larger rodents such as the rat. However, few reports exist on the use of this paradigm in the mouse. The objective of this study was to investigate a model of branch and central retinal vein occlusion in the mouse and characterize in vivo longitudinal retinal morphology alterations using spectral domain optical coherence tomography. Retinal veins were experimentally occluded using laser photocoagulation after intravenous application of Rose Bengal, a photo-activator dye enhancing thrombus formation. Depending on the number of veins occluded, variable amounts of capillary dropout were seen on fluorescein angiography. Vascular endothelial growth factor levels were markedly elevated early and peaked at day one. Retinal thickness measurements with spectral domain optical coherence tomography showed significant swelling (pvein occlusion model in the mouse carries several advantages over its use in other larger species, such as access to a vast range of genetically modified animals. Retinal changes after experimental retinal vein occlusion in this mouse model can be non-invasively quantified by spectral domain optical coherence tomography, and may be used to monitor effects of potential therapeutic interventions. PMID:25775456

  13. Chemosuppression of retinal axon growth by the mouse optic chiasm.

    Science.gov (United States)

    Wang, L C; Rachel, R A; Marcus, R C; Mason, C A

    1996-11-01

    To determine whether diffusible guidance cues direct retinal axon growth and divergence at the optic chiasm, we cocultured mouse retinal and chiasm explants in collagen gels. The chiasm reduced retinal neurite lengths and numbers, but did not affect commissural or pontine neurite growth. This reduction in growth was equal for all retinal quadrants and occurred without reorienting the direction of neurite extension. The floor plate, another midline guidance locus, also suppressed retinal neurite outgrowth, whereas cortex or cerebellum explants did not. Growth suppression was not mediated by netrin-1, which instead enhanced retinal neurite extension. We propose that chemosuppression may be a general guidance mechanism that acts in intermediate targets to prime growth cones to perceive other, more specific cues. PMID:8938118

  14. Preclinical models to investigate retinal ischemia: Advances and drawbacks

    Directory of Open Access Journals (Sweden)

    AkshayAnand

    2012-05-01

    Full Text Available Retinal ischemia is a frequent source of irreparable visual impairment affecting over a hundred million individuals in the world. It is associated with a wide range of retinal disorders like ischemic optic neuropathies, obstructive retinopathies, carotid occlusive disorders, diabetic retinopathy and glaucoma. Compared to other tissues retina has a higher metabolic rate; any disruption in blood supply can have an effect on the supply of oxygen leading to retinal ischemia. If occlusion is not rescued the outcome is irreversible with ischemic and apoptotic cascades resulting in cell death. In addition to in-vitro models, animal models are necessary to further our understanding of the etiology, pathology, and evolution of retinal ischemia besides the evaluation, development, and improvement of therapeutic strategies. The various existing animal models of retinal ischemia are characterised by obstruction of retinal circulation that allows the study of neurovascular changes. In this review we provide an overview of major models and emerging preclinical therapeutic strategies.

  15. Adaptive Optics Technology for High-Resolution Retinal Imaging

    Directory of Open Access Journals (Sweden)

    Giuseppe Lombardo

    2012-12-01

    Full Text Available Adaptive optics (AO is a technology used to improve the performance of optical systems by reducing the effects of optical aberrations. The direct visualization of the photoreceptor cells, capillaries and nerve fiber bundles represents the major benefit of adding AO to retinal imaging. Adaptive optics is opening a new frontier for clinical research in ophthalmology, providing new information on the early pathological changes of the retinal microstructures in various retinal diseases. We have reviewed AO technology for retinal imaging, providing information on the core components of an AO retinal camera. The most commonly used wavefront sensing and correcting elements are discussed. Furthermore, we discuss current applications of AO imaging to a population of healthy adults and to the most frequent causes of blindness, including diabetic retinopathy, age-related macular degeneration and glaucoma. We conclude our work with a discussion on future clinical prospects for AO retinal imaging.

  16. Surgical Treatment of Retinal Detachment Following Acute Retinal Necrosis Syndrome: Surgical Results in Four Patients.

    Directory of Open Access Journals (Sweden)

    Chiun-Ho Hou

    2003-11-01

    Full Text Available Background: Acute retinal necrosis (ARN syndrome is an uncommon but severe oculardisease that typically affects otherwise healthy individuals. It is frequentlycomplicated with retinal detachment and the visual prognosis in such patientsis usually poor.Methods: We operated on four eyes in four patients from 1999 through 2001. Threeophthalmologists in our hospital did these operations, respectively. The surgicalmethods included pars plana vitrectomy, lensectomy, encircling scleralbuckling combined with membrane dissection, air-fluid exchange, endolaserphotocoagulation, and retinal tamponade with silicone oil or perfluoropropanegas.Results: Three patients received one operation and the other one needed a secondoperation to release the retinal traction. One patient needed a lensectomy atthe time of vitrectomy. Macular attachment was achieved in all four eyes(100%. Vision improved in two patients but none achieved visual acuity betterthan 20/200. The complications were cataract in three patients, macularpucker in three, and silicone keratopathy in one.Conclusion: Our results suggest that modern vitrectomy techniques provide a very highretinal attachment rate in patients with retinal detachment following ARNsyndrome.

  17. Effects of pyruvate on retinal oxidative damage and retinal ultrastructure in diabetic rats

    Directory of Open Access Journals (Sweden)

    Yan-Xiu Qi

    2014-12-01

    Full Text Available AIM:To investigate the changes of retinal histology and oxidative stress in diabetic retinopathy and its reversal by pyruvate in diabetic rats. METHODS:Eighty Wistar rats were divided into 3 groups: control group(20 rats, model group(30 ratsand treatment group(30 rats. After streptozotocin(STZinduced diabetes mellitus in the model group and the treatment group, the treatment group received 2% pyruvate in diet and drinking. The changes of body weight and blood glucose were observed and the changes of glutathione peroxidase(GSH-PX, malonie dialdehyde(MDA, and Na+-K+-ATPase levels of retinal tissue and retinal ultrastructure were investigated in three groups at 12wk after occurrence of diabetes. RESULTS:Compared with control group, the body weight of the model group were significantly decreased, the activities of GSH-PX and ATP in the retina of diabetic rats were significantly lower, the MDA was signigicantly higher and significant changes occurred in retinal ultrastructure. Compared with model group, the blood glucose of the treatment group had no significant changes. However, the activities of GSH and ATP in the retina of diabetic rats were higher, the MDA was lower and the retinal ultrastructure was comparatively mild. CONCLUSION:Pyruvate can alleviate oxidatie stress reaction, improve the energy metabolism of retina, and delay the development of retinopathy.

  18. Organoprotective effects of benasepril in patients with arterial hypertension

    Directory of Open Access Journals (Sweden)

    V.S. Zadionchenko

    2006-01-01

    Full Text Available Aim. To evaluate antihypertensive efficiency of benasepril therapy (Lotensin, Novartis and its effects on microcirculation, endothelium function, system of cytoprotection, ophthalmoscopic and functional characteristics of eye retina in patients with arterial hypertension (AH.Material and methods. 40 patients with AH of 1-3 degree (AH1, AH2, and AH3 were studied. After wash-out period all patients were prescribed benasepril 5-10 mg daily. If necessary, hydrochlorothiazide 12,5 mg daily was added. Treatment lasted during 6 months. Patients were examined at the beginning and at the end of the study. Ambulatory blood pressure (BP monitoring was carried out. Microcirculation was assessed by method of laser Doppler flowmetry. Stable plasma metabolites of nitric oxide (NO were determined by spectral photometry. Cytoprotection was assessed by content of heat shock proteins (HSP70 in leucocytes of peripheral blood. Ophthalmoscopy, color and contrast static campimetry with evaluation of sensory-motor reaction (SMR time in different fields of vision were carried out.Results. Therapy with benasepril allowed to improve daily profile of BP and to reach its target level in all AH patients. Number of patients with spastic type of microcirculation decreased. Functional condition of endothelium improved which revealed in normalization of endothelial production of NO. Therapy with benasepril resulted in intracellular HSP70 level decrease which testified restriction of cellular destruction. The cytoprotective effect of benasepril was stronger in patient with severe AH. Therapy with benasepril resulted in SMR time decrease which signifies its positive influence on retinal blood flow. Evaluation of contrast and color sensitiveness of retina allowed to reveal and quantitatively assess earlier dysfunctions of retinal tissue perfusion, compared to ophthalmoscopy.Conclusion. Benasepril is an efficient antihypertensive drug which improves microcirculation, endothelium function and retinal perfusion, has cytoprotective effect. Color and contrast static campimetry is an adequate method for quantitative assessment of retinal perfusion and allows objectively to evaluate damage of eye as target organ of AH.

  19. Computer algorithms for the automated measurement of retinal arteriolar diameters

    OpenAIRE

    Chapman, N.; Witt, N.; Gao, X.; Bharath, A.; Stanton, A.; Thom, S.; Hughes, A.

    2001-01-01

    AIMS—Quantification of retinal vascular change is difficult and manual measurements of vascular features are slow and subject to observer bias. These problems may be overcome using computer algorithms. Three automated methods and a manual method for measurement of arteriolar diameters from digitised red-free retinal photographs were compared.?METHODS—60 diameters (in pixels) measured by manual identification of vessel edges in red-free retinal images were compared with diameters measure...

  20. 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...

  1. Structural Changes in Individual Retinal Layers in Diabetic Macular Edema

    OpenAIRE

    Tomoaki Murakami; Nagahisa Yoshimura

    2013-01-01

    Optical coherence tomography (OCT) has enabled objective measurement of the total retinal thickness in diabetic macular edema (DME). The central retinal thickness is correlated modestly with visual impairment and changes paradoxically after treatments compared to the visual acuity. This suggests the clinical relevance of the central retinal thickness in DME and the presence of other factors that affect visual disturbance. Recent advances in spectral-domain (SD) OCT have provided better deline...

  2. CMV retinitis in China and SE Asia: the way forward

    OpenAIRE

    Heiden David; Saranchuk Peter

    2011-01-01

    Abstract AIDS-related CMV retinitis is a common clinical problem in patients with advanced HIV/AIDS in China and Southeast Asia. The disease is causing blindness, and current clinical management, commonly characterized by delayed diagnosis and inadequate treatment, results in poor clinical outcomes: 21% - 36% of eyes with CMV retinitis are already blind at the time the diagnosis is first established by an ophthalmologist. CMV retinitis also identifies a group of patients at extraordinary risk...

  3. Retinal microglia are activated by systemic fungal infection

    OpenAIRE

    Meneu Flores, Victoria; Noailles, Agustina; Megías, Javier; Gómez Vicente, Violeta; Carpena, Núria; Gil, María Luisa; Gozalbo, Daniel; Cuenca Navarro, Nicolás

    2014-01-01

    Purpose: To determine whether systemic fungal infection could cause activation of retinal microglia and therefore could be potentially harmful for patients with retinal degenerative diseases. Methods: Activation of retinal microglia was measured in a model of sublethal invasive candidiasis in C57BL/6J mice by (i) confocal immunofluorescence and (ii) flow cytometry analysis, using anti-CD11b, anti-Iba1, anti-MHCII and anti-CD45 antibodies. Results: Systemic fungal infection causes activation o...

  4. Treatment of macular edema due to retinal vein occlusions

    OpenAIRE

    Channa R; Smith M; Campochiaro P

    2011-01-01

    Roomasa Channa, Michael Smith, Peter A CampochiaroDepartments of Ophthalmology and Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD, USA Abstract: Retinal vein occlusion (RVO) is a prevalent retinal vascular disease, second only to diabetic retinopathy. Previously there was no treatment for central retinal vein occlusion (CRVO) and patients were simply observed for the development of severe complications, generally resulting in poor visual outcomes. The only treatm...

  5. Induced chorioretinal venous anastomosis in experimental retinal branch vein occlusion.

    OpenAIRE

    Mcallister, I. L.; Yu, D. Y.; Vijayasekaran, S.; Barry, C.; Constable, I.

    1992-01-01

    Iatrogenic retinal vein to choroidal vein anastomoses were created using laser photocoagulation in six of seven dog eyes in which a partial branch retinal vein occlusion had previously been created photochemically. A similar attempt to create an anastomosis was made in six control eyes in which no branch vein occlusion was present. In the eyes in which a branch retinal vein had been created, a venous chorioretinal anastomosis appeared to be present by 3 to 6 weeks. In three control eyes simil...

  6. Adaptive Optics Technology for High-Resolution Retinal Imaging

    OpenAIRE

    Giuseppe Lombardo; Mariacristina Parravano; Nicholas Devaney; Marco Lombardo; Sebastiano Serrao

    2012-01-01

    Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effects of optical aberrations. The direct visualization of the photoreceptor cells, capillaries and nerve fiber bundles represents the major benefit of adding AO to retinal imaging. Adaptive optics is opening a new frontier for clinical research in ophthalmology, providing new information on the early pathological changes of the retinal microstructures in various retinal diseases. We have ...

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

    OpenAIRE

    Watanabe, Y.; 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...

  8. Management of varicella zoster virus retinitis in AIDS

    OpenAIRE

    Moorthy, R.; Weinberg, D.; Teich, S.; Berger, B.; Minturn, J.; Kumar, S.; Rao, N.; Fowell, S.; Loose, I.; Jampol, L.

    1997-01-01

    AIMS/BACKGROUND—Varicella zoster virus retinitis (VZVR) in patients with AIDS, also called progressive outer retinal necrosis (PORN), is a necrotising viral retinitis which has resulted in blindness in most patients. The purposes of this study were to investigate the clinical course and visual outcome, and to determine if the choice of a systemic antiviral therapy affected the final visual outcome in patients with VZVR and AIDS.?METHODS—A review of the clinical records of 20 patients w...

  9. Nanocarriers of nanotechnology in retinal diseases.

    Science.gov (United States)

    Al-Halafi, Ali M

    2014-10-01

    We are approaching a new era of retinal pharmacotherapy where new drugs are rapidly being worked out for the treatment of posterior-segment disease. Recent development in ocular drug delivery systems research has provided new insights into drug development, and the use of nanoparticles for drug delivery is thus a promising excellent approach for advanced therapy of ocular diseases. The primary goal is to develop a variety of drug delivery systems to complement and further enhance the efficacy of the available new medications. The ideal sustained release technology will provide a high level of safety with continuous release over an extended period of time while maintaining almost total drug bioactivity. The use of nanocarriers, such as cyclodextrin nanoparticle suspension, liposomes, nanospheres and, nanoemulsions for gene therapy of retinal diseases has been highlighted in this review. PMID:25473348

  10. Retinal injury from a welding arc

    International Nuclear Information System (INIS)

    An 18-year-old man stared at a welding arc for approximately ten minutes, sustaining moderate facial erythema, keratoconjunctivitis, marked visual loss, a pupillary abnormality, and a retinal injury accompanied by a dense central scotoma and peripheral field constriction. A residual, partially pigmented foveal lesion remained after 16 months, with normal visual acuity. Since the degree of keratoconjunctivitis and facial erythema was known, we substantiated the duration of exposure to the arc by weighting the known action spectrum of moderate ultraviolet erythema with the ultraviolet spectral irradiance measurements of the arc. From the radiometric measurements of the visible brightness and visible and near infrared spectrum of the arc and from knowledge of pupil size, we calculated the retinal exposure dose rate, which was less than normally considered necessary to produce a chorioretinal burn. This case may provide a clinical example of photic maculopathy recently reported in experimental investigations

  11. Supervised retinal biometrics in different lighting conditions.

    Science.gov (United States)

    Azemin, Mohd Zulfaezal Che; Kumar, Dinesh K; Sugavaneswaran, Lakshmi; Krishnan, Sridhar

    2011-01-01

    Retinal image has been considered for number of health and biometrics applications. However, the reliability of these has not been investigated thoroughly. The variation observed in retina scans taken at different times is attributable to differences in illumination and positioning of the camera. It causes some missing bifurcations and crossovers from the retinal vessels. Exhaustive selection of optimal parameters is needed to construct the best similarity metrics equation to overcome the incomplete landmarks. In this paper, we extracted multiple features from the retina scans and employs supervised classification to overcome the shortcomings of the current techniques. The experimental results of 60 retina scans with different lightning conditions demonstrate the efficacy of this technique. The results were compared with the existing methods. PMID:22255209

  12. Carotid Artery Disease

    Science.gov (United States)

    ... involves the placement of a small flexible tube (catheter) into an artery from the groin. The catheter is then directed to the neck to reach ... of atherosclerosis (build-up of plaque in the peripheral, coronary or carotid arteries) • Age (men have a ...

  13. Pulmonary Arterial Hypertension

    Science.gov (United States)

    ... Arterial Hypertension? With PAH, the arteries become too narrow to handle the amount of blood that must be pumped through the lungs. This causes several things to happen: a backup of blood in the veins returning blood to the heart; an increase in ...

  14. Bilateral Serous Retinal Detachments Associated with Accelerated Hypertensive Choroidopathy

    Science.gov (United States)

    Hirano, Yoshio; Yasukawa, Tsutomu; Ogura, Yuichiro

    2010-01-01

    Purpose. We report a case of hypertensive choroidopathy with bilateral serous retinal detachments. Patient. A 50-year-old man underwent bilateral serous retinal detachments. Retinal arteriolar narrowing, vascular tortuosity, and arteriovenous nicking were identified in both eyes. The blood pressure was 206/125?mmHg. The patient was diagnosed with bilateral hypertensive choroidopathy and treated with oral antihypertensive treatment. Results and discussion. One month after antihypertensive treatment, the serous retinal detachments resolved and the visual acuity improved. A patient with those findings should be considered as having hypertensive choroidopathy and treated as soon as possible. PMID:20981311

  15. The influence of retinal eye diseases on painting.

    Science.gov (United States)

    Ivaniševi?, Petar; Ivaniševi?, Milan

    2015-03-01

    In this work the possible influences of some retinal eye problems on paintings of several famous artists are considered. The change of painting styles and artistic expression in different periods and ages in a group of world-wide well-known painters are described and correlated with known or suspected retinal diseases. Some of them largely became recognizable because of that. Contemplations are offered about the effects of retinal diseases in the works of Degas, Munch, Cézanne, O'Keeffe, Constable and Goya. Retinal eye diseases have a significant impact on the work of selected famous painters. PMID:26040100

  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. Implantable multilayer microstrip antenna for retinal prosthesis: antenna testing.

    Science.gov (United States)

    Permana, Hans; Fang, Qiang; Rowe, Wayne S T

    2012-01-01

    Retinal prosthesis has come to a more mature stage and become a very strategic answer to Retinitis Pigmentosa (RP) and Age-related Macular Degeneration (AMD) diseases. In a retinal prosthesis system, wireless link holds a great importance for the continuity of the system. In this paper, an implantable multilayer microstrip antenna was proposed for the retinal prosthesis system. Simulations were performed in High Frequency Structure Simulator (HFSS) with the surrounding material of air and Vitreous Humor fluid. The fabricated antenna was measured for characteristic validation in free space. The results showed that the real antenna possessed similar return loss and radiation pattern, while there was discrepancy with the gain values. PMID:23366231

  18. 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.

  19. Safety with laser during retinal therapy : an electroretinographic study

    OpenAIRE

    E. El-Sayed; Talaat, M.; Sallam, A.

    1994-01-01

    Studies of the retinal sensitivity, as reflected in the ERG records, have been made, before, during, and after exposure of the eye to an argon laser beam ( > = 488 nm ; intensity 1 mW/cm2 ; durations 0.12 and 0.25 sec). The applied retinal load thus was similar as that during retinal treatments. The ERG records were carried out at different temperatures (10 - 30°C) for both light and dark adapted eyes. The aim of this study was to assess the best suitable conditions for retinal laser treatmen...

  20. 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.

  1. 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.

  2. [Scleral buckling for Rhegmatogenous retinal detachment].

    Science.gov (United States)

    Hejsek, L; Dusová, J; Stepanov, A; Rozsíval, P

    2014-06-01

    Rhegmatogenous retinal detachment (RRD) is the separation of the sensory retina from the pigment epithelium (RPE). RRD is caused by a retinal tear in the periphery and the vitreoretinal (VR) traction, which allows access of the vitreous fluid to the subretinal space. Treatment of symptomatic retinal detachment is currently surgical only. Surgical options are intraocular and extraocular. This is the retrospective evaluation of the group of 17 eyes of 17 patients with RRD, which were operated by scleral buckling. Patients were 9 men and 8 women, age range 19-61 (median 46) years. The observation period is 1-13 months (median 7). The possible types of external interventions procedure were used only two: the radial plombage (in one case double) and cerclage. 15 patients (88 %) were phakic, and 2 were pseudophakic. In 12 eyes (71 %) were the quadrant RRDs, 2 eyes had dialysis in periphery of the retina, 1x it was the top half and 1x bottom half, and 1 patient had a subtotal RRD. In 9 (53 %) cases were used type of operation cryocoagulation with radial buckle and in 8 cases cryocoagulation with the cerclage. In four cases, was injected the gas tamponade into the vitreous at the end of the surgery. Primary attaching the retina occurred in 16 cases (94 %) and the retina remained flat in 14 eyes (82.4% ), in 2 cases occurred re-detachment (11.7 %). Preoperative best corrected visual acuity (BCVA) ranged from hand movement to 20/20 (average Snellen equivalent 20/63) and postoperative BCVA was 1/50 - 20/20 (average 20/50). Improving BCVA was statistically significant (Wilcoxon p=0.01). We consider the cryosurgical procedure for phakic eyes as the gold standard of the surgical treatment of uncomplicated rhegmatogenous retinal detachment. The main reason for the eventual failure of this technique is persistent vitreous traction and proliferative vitreoretinopathy (PVR). PMID:25032797

  3. Computer-aided quantification of retinal neovascularization

    OpenAIRE

    Stahl, A.(RWTH Aachen University, III. Physikalisches Institut B, Aachen, Germany); Connor, K M; Sapieha, P; Willett, K. L.; Krah, N M; Dennison, R. J.; Chen, J.; Guerin, K. I.; Smith, L E H

    2009-01-01

    Rodent models of retinal angiogenesis play a pivotal role in angiogenesis research. These models are a window to developmental angiogenesis, to pathological retinopathy, and are also in vivo tools for anti-angiogenic drug screening in cancer and ophthalmic research. The mouse model of oxygen-induced retinopathy (OIR) has emerged as one of the leading in vivo models for these purposes. Many of the animal studies that laid the foundation for the recent breakthrough of anti-angiogenic treatments...

  4. Avulsão vascular retiniana / Avulsed retinal vessels

    Scientific Electronic Library Online (English)

    Leonardo Pérez, Zeni; Manuel Augusto Pereira, Vilela.

    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 las [...] er 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. Abstract in english 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 m [...] inimum 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.

  5. Retinal Encoding of Ultrabrief Shape Recognition Cues

    OpenAIRE

    Greene, Ernest

    2007-01-01

    Shape encoding mechanisms can be probed by the sequential brief display of dots that mark the boundary of the shape, and delays of less that a millisecond between successive dots can impair recognition. It is not entirely clear whether this is accomplished by preserving stimulus timing in the signal being sent to the brain, or calls for a retinal binding mechanism. Two experiments manipulated the degree of simultaneity among and within dot pairs, requiring also that the pair members be in the...

  6. Invited review: fluphenazine augments retinal oxidative stress.

    Science.gov (United States)

    Toler, Steven M

    2005-08-01

    Recently, fluphenazine, a phenothiazine neuroleptic, has been associated with idiosyncratic retinopathy. Neuroleptic-induced retinopathy appears to be isolated to only a few structurally related phenothiazines, suggesting that the causality is not the result of dopamine antagonism. The chemical structure of fluphenazine is very similar to that of chlorpromazine and thioridazine, agents known to produce retinopathy. Like chlorpromazine and thioridazine, fluphenazine may be oxidized by retinal cytochrome P450 and/or myeloperoxidase to an electrophile, producing injury in susceptible patients. PMID:16117689

  7. Cell transplantation strategies for retinal repair

    OpenAIRE

    West, EL; Pearson, RA; MacLaren, RE; Sowden, JC; Ali, RR

    2009-01-01

    Cell transplantation is a novel therapeutic strategy to restore visual responses to the degenerate adult neural retina and represents an exciting area of regenerative neurotherapy. So far, it has been shown that transplanted postmitotic photoreceptor precursors are able to functionally integrate into the adult mouse neural retina. In this review, we discuss the differentiation of photoreceptor cells from both adult and embryonic-derived stem cells and their potential for retinal cell transpla...

  8. Interconnection between brain and retinal neurodegenerations.

    Science.gov (United States)

    Jindal, Vishal

    2015-06-01

    The eye is a special sensory organ, which is basically an extension of the brain. Both are derived from neural tube and consist of neurons. Therefore, diseases of both the brain and eye should have some similarity. Neurodegenerative disorders like Alzheimer's disease (AD) is the major cause of dementia in the world. Amyloid deposition in the cerebral cortex and hippocampal region is the basic pathology in AD. But along with it, there are various changes that take place in the eye, i.e., abnormal pupillary reaction, decreased vision, decreased contrast sensitivity, visual field changes, loss of retinal ganglionic cells and retinal fiber layer, peripapillary atrophy, increased cup-disk ratio, retinal thinning, tortuosity of blood vessels, and deposition of A?-like substance in the retina. And these changes are present in the early part of the disease when only mild cognitive impairment is there. As the brain is covered by a hard bony skull which makes it difficult to directly visualize the changes occurring in the brain at molecular levels, finer details of disease progression are not available with us. But the eye is the window of the brain; with advanced modern techniques, we can directly visualize the changes in the retina at a very fine level. Therefore, by depicting neurodegenerative changes in the eye, we can diagnose and manage AD at very early stages. Along with it, retinal neurodegenerations like glaucoma and age-related macular degeneration (ARMD) are the major cause of loss of vision, and still, there are no effective treatment modalities for these blinding conditions. So if we can understand its pathogenesis and progression by correlating with brain neurodegenerations, we can come up with a better therapy for glaucoma and ARMD. PMID:24826919

  9. 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

  10. Central Retinal Vein Occlusion in a Patient with Retinal Vasculitis and Crohn's Disease

    Science.gov (United States)

    Figueiredo, Lígia; Rothwell, Renata; Brandão, Arnaldo

    2014-01-01

    The authors report a rare case of a 47-year-old woman with Crohn's disease (CD) who presented with retinal vasculitis and central retinal vein occlusion (CRVO) during remission. The patient complained of sudden painless visual loss in her left eye (OS). Ophthalmologic evaluation revealed a best corrected visual acuity (BCVA) of 20/20 in the right eye and hand movements in OS. Ophthalmoscopy and fluorescein angiography of OS showed signs of nonischemic CRVO and extensive vasculitis. She was treated with oral prednisolone, mercaptopurine, and intravitreal bevacizumab in OS. After 1 month of treatment, VA of OS improved to 5/10 and after 1 year it was 10/10 with complete resolution of retinal vasculitis and nonischemic CRVO. PMID:25506451

  11. Neurogenin3 promotes early retinal neurogenesis.

    Science.gov (United States)

    Ma, Wenxin; Yan, Run-Tao; Mao, Weiming; Wang, Shu-Zhen

    2009-02-01

    The transcriptional regulatory network governing the establishment of retinal neuron diversity is not well delineated. We report experimental results suggesting proneural gene neurogenin3 (ngn3) participating in this regulatory network. Retinal expression of chick ngn3 was confined to early neurogenesis. Overexpression of ngn3 in chick retina reduced cell proliferation and expanded the population of ganglion cells into the territory normally occupied by amacrine cells. Ngn3 overexpression altered the expression of a number of regulatory genes, including ash1, ath3, ath5, chx10, neuroD, ngn1, ngn2, and NSCL1. Early gene ngn1 was induced, but ash1, ngn2, ath3, and chx10, whose expressions persist through later phases of neurogenesis, were down-regulated. Expression of ath5 was up-regulated at the locale corresponding to young ganglion cells, but was down-regulated at the locale corresponding to progenitor cells. These results suggest that ngn3 regulates retinal neurogenesis by inducing regulatory genes for early-born neurons and repressing those for later-born cells. PMID:19028584

  12. Gene replacement therapy for retinal CNG channelopathies.

    Science.gov (United States)

    Schön, Christian; Biel, Martin; Michalakis, Stylianos

    2013-10-01

    Visual phototransduction relies on the function of cyclic nucleotide-gated channels in the rod and cone photoreceptor outer segment plasma membranes. The role of these ion channels is to translate light-triggered changes in the second messenger cyclic guanosine 3'-5'-monophosphate levels into an electrical signal that is further processed within the retinal network and then sent to higher visual centers. Rod and cone photoreceptors express distinct CNG channels. The rod photoreceptor CNG channel is composed of one CNGB1 and three CNGA1 subunits, whereas the cone channel is formed by one CNGB3 and three CNGA3 subunits. Mutations in any of these channel subunits result in severe and currently untreatable retinal degenerative diseases like retinitis pigmentosa or achromatopsia. In this review, we provide an overview of the human diseases and relevant animal models of CNG channelopathies. Furthermore, we summarize recent results from preclinical gene therapy studies using adeno-associated viral vectors and discuss the efficacy and translational potential of these gene therapeutic approaches. PMID:23861024

  13. 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.

  14. 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.

  15. 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.; Nicholas J. Turro; 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...

  16. Retinal ganglion cell (RGC) programmed necrosis contributes to ischemia-reperfusion-induced retinal damage.

    Science.gov (United States)

    Dvoriantchikova, Galina; Degterev, Alexei; Ivanov, Dmitry

    2014-06-01

    Retinal ischemia-reperfusion (IR) injury remains a common cause of blindness and has a final pathway of retinal ganglion cell (RGC) death by apoptosis and necrosis. RGC apoptosis was intensively studied in IR injury, while RGC necrosis did not receive nearly enough consideration since it was viewed as an accidental and unregulated cellular event. However, there is evidence that necrosis, like apoptosis, can be implemented by a programmed mechanism. In this study, we tested the role of RGC programmed necrosis (necroptosis) in IR-induced retinal injury. We employed the mouse model of retinal IR injury for in vivo experiments. The oxygen and glucose deprivation (OGD) model was used as an IR model in vitro. Primary RGCs were isolated by an immunopanning technique. Necrostatin 1 (Nec1) was used to inhibit necroptosis in in vitro and in vivo experiments. The changes in gene expression were assessed by quantitative RT-PCR. The distribution of proteins in the retina and in RGC cultures was evaluated by immunohistochemistry and immunocytochemistry, respectively. Our data suggest that proteins (Ripk1 and Ripk3), which initiate necroptosis, were present in normal and ischemic RGCs. Treatment with Nec1 significantly reduced retinal damage after IR. Increased RGC survival and reduced RGC necrosis following OGD were observed in Nec1-treated cultures. We found significantly reduced expression of genes coding pro-inflammatory markers Il1b, Ccl5, Cxcl10, Nos2 and Cybb in Nec1-treated ischemic retinas. Thus, our findings suggest that RGC necroptosis contributes to retinal damage after IR through direct loss of cells and induction of associated inflammatory responses. PMID:24751757

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

    Science.gov (United States)

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

    2009-03-01

    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 progression. The data presented in this contribution were acquired with a high speed (25,000 A-scans/s), high resolution (4.5 microm) spectral OCT prototype instrument operating in the ophthalmology clinic. PMID:19259255

  18. 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.

  19. Object size, spatial-frequency content and retinal contrast

    Science.gov (United States)

    Rizzi, Alessandro

    2010-02-01

    Recent interest in HDR scene capture and display has stimulated measurements of the usable range of contrast information for human vision. These experiments have led to a model that calculates the retinal contrast image. A fraction of the light from each scene pixel is scattered to all retinal pixels. The amount of scattered light decreases with distance from the other pixels. By summing the light falling on each retinal pixel from all the scene pixels we can calculate the retinal image contrast. As objects, such as text letters, get smaller, their retinal contrast gets lower, even though the scene contrast is constant. This paper studies the Landolt C data, a commonly used test targets for measuring visual acuity, using three frameworks. First, it compares the visual acuity measurements with the receptor mosaic dimension. Second, discusses the Campbell and Robson's experiments and the limits of the Contrast Sensitivity Function (CSF). Third, the paper reports the calculated retinal stimulus after intraocular scatter of both Landolt C and Campbell and Robson's stimuli. These three different frameworks are useful in understanding limits of human vision. Each approach gives only one piece of the puzzle. Retinal contrast, CSF, and retinal cone spacing all influence our understanding of human vision limits. We have analyzed Landolt C and CSF using retinal contrast. Glare effect on Landolt C shows that retinal images are significantly different from target images. Veiling glare of the sine-wave stimuli used by Campbell and Robson to measure CSF, results in a retinal contrast decrease. This, above 3-4 cpd, correlates well with the data reported by them.

  20. Retinal fluorescein contrast arrival time of young patients with the hepatosplenic form of the Schistosomiasis mansoni

    Directory of Open Access Journals (Sweden)

    Ana Catarina Delgado de Souza

    2002-10-01

    Full Text Available Schistosoma mansoni is responsible for lesions that can alter the hemodinamic of the portal venous circulation, lung arterial and venous sistemic systems. Therefore, hemodinamic changes in the ocular circulation of mansonic schistosomotic patients with portal hypertension and hepatofugal venous blood flow is also probable. The purpose of this study was to determine the fluorescein contrast arrival time at the retina of young patients with the hepatosplenic form of schistosomiasis, clinically and surgically treated. The control group included 36 non schistosomotic patients, mean age of 17.3 years, and the case group was represented by 25 schistosomotic patients, mean age of 18.2 years, who were cared for at The University Hospital (Federal University of Pernambuco, Brazil, from 1990 to 2001. They underwent digital angiofluoresceinography and were evaluated for the contrast arrival time at the early retinal venous phase of the exam. Both groups were ophthalmologically examined at the same hospital (Altino Ventura Foundation, Recife, Brazil, using the same technique. There was retardation of the retinal contrast arrival time equal or more than 70 sec in the eyes of three schistosomotic patients (12% and in none of the control group, however, the mean contrast arrival time between the two groups were not statistically different. These findings lend support to the hypothesis that there could be a delay of the eye venous blood flow drainage.

  1. Investigation of retinal vessel autoregulation using real-time spectral domain Doppler optical coherence tomography

    Science.gov (United States)

    Bower, Bradley A.; Zhao, Mingtao; Izatt, Joseph A.

    2006-02-01

    Investigation of the autoregulatory mechanism of human retinal perfusion was conducted with a novel real-time spectral domain Doppler optical coherence tomography (SDOCT) system. Volumetric, time-sequential, and Doppler flow imaging was performed in the superior arcade region on normal healthy subjects breathing normal room air and 100% oxygen. The real-time Doppler SDOCT system displays fully processed, high-resolution [512 (axial) x 1000 (lateral) pixels] B-scans at 17 frames/sec in volumetric and time-sequential imaging modes, and also displays fully processed overlaid color Doppler flow images comprising 512 (axial) x 500 (lateral) pixels at 6 frames/sec. OCT fundus images generated from volumetric datasets updated in real time (up to 2 fundus images/sec for 100 x 100 pixel volumes) were used to image and localize retinal vessels for time-sequential and Doppler flow analysis. In preliminary measurements, data acquired following 5 minutes of 100% oxygen inhalation was compared with that acquired 5 minutes post-inhalation. The same arterial segments examined at both time points exhibit constriction in vessel diameter under pure oxygen inhalation of up to 7% and reduction in peak flow velocity as great as 38%, both of which are in good agreement with previous laser Doppler velocimetry studies.

  2. Embolismos retinianos por colesterol tras angiografía coronaria Retinal cholesterol embolization after coronary angiography

    Directory of Open Access Journals (Sweden)

    A. Sampedro

    2006-07-01

    Full Text Available Caso clínico: Se presenta un paciente con múltiples embolismos retinianos por colesterol en ambos ojos, tras una coronariografía. Asociaba además, manifestaciones renales, cutáneas y cardíacas del Síndrome de Embolismo por Colesterol (CES, falleciendo a las 10 semanas. La autopsia confirmó la presencia de cristales de colesterol en múltiples órganos. Discusión: Las placas ateromatosas, durante un procedimiento invasivo arterial, pueden ser origen de embolizaciones masivas por colesterol. La presencia de émbolos retinianos ayuda al diagnóstico del síndrome, sobre todo cuando se acompaña de sintomatología sistémica. El pronóstico vital es malo por la insuficiencia multiorgánica.Case report: We report a patient with multiple cholesterol retinal embolism in both eyes following coronary angiography. She also had associated renal, skin and cardiac manifestations of the Cholesterol Embolization Syndrome (CES and died 10 weeks later. Autopsy revealed cholesterol crystal emboli in several organs. Discussion: Atheromatous plaques can be ruptured and displaced during a diagnostic catheterisation, and thus can be a potential source of these massive emboli. Retinal cholesterol crystals help to establish the diagnosis of the syndrome, particularly when other systemic manifestations exist. When this complication occurs, the prognosis can be devastating because of associated multiorgan failure.

  3. Three-dimensional reconstruction of blood vessels extracted from retinal fundus images.

    Science.gov (United States)

    Martinez-Perez, M Elena; Espinosa-Romero, Arturo

    2012-05-01

    We present a 3D reconstruction of retinal blood vessel trees using two views of fundus images. The problem is addressed by using well known computer vision techniques which consider: 1) The recovery of camera-eyeball model parameters by an auto-calibration method. The camera parameters are found via the solution of simplified Kruppa equations, based on correspondences found by a LMedS optimisation correlation between pairs of eight different views. 2) The extraction of blood vessels and skeletons from two fundus images. 3) The matching of corresponding points of the two skeleton trees. The trees are previously labelled during the analysis of 2D binary images. Finally, 4) the lineal triangulation of matched correspondence points and the surface modelling via generalised cylinders using diameter measurements extracted from the 2D binary images. The method is nearly automatic and it is tested with 2 sets of 10 fundus retinal images, each one taken from different subjects. Results of 3D vein and artery trees reconstructions are shown. PMID:22565765

  4. Agujero retiniano en polo posterior secundario a un foco de retinitis por cándida Posterior retinal hole secondary to a candida retinitis

    Directory of Open Access Journals (Sweden)

    ML Álvarez-Suárez

    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.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-retinal 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.

  5. 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.

  6. Vertebrobasilar Artery Occlusion

    Directory of Open Access Journals (Sweden)

    Schoen, Jessica

    2011-05-01

    Full Text Available The presentation of vertebrobasilar artery occlusion varies with the cause of occlusion and location of ischemia. This often results in delay in diagnosis. Areas of the brain supplied by the posterior circulation are difficult to visualize and usually require angiography or magnetic resonance imaging. Intravenous thrombolysis and local-intra arterial thrombolysis are the most common treatment approaches used. Recanalization of the occluded vessel significantly improves morbidity and mortality. Here we present a review of the literature and a case of a patient with altered mental status caused by vertebrobasilar artery occlusion. [West J Emerg Med. 2011;12(2:233-239.

  7. Coronary artery aneurysms

    International Nuclear Information System (INIS)

    Seven saccular coronary artery aneurysms have been demonstrated in the course of 1452 selective coronary artery angiograms. In six patients they were arterio-sclerotic; in one patient the aneurysm must have been congenital or of mycotic-embolic origin. The differential diagnosis between true aneurysms and other causes of vascular dilatation is discussed. Coronary artery aneurysms have a poor prognosis because of the possibility of rupture with resultant cardiac tamponade, or the development of thrombo-embolic myocardial infarction. These aneurysms can only be diagnosed by means of coronary angiography and require appropriate treatment. (orig.)

  8. Blindness and visual impairment due to retinal diseases

    OpenAIRE

    Shaheen Shah

    2009-01-01

    This General Assembly, compared to others in the past, had retinal diseases as a cause of visual impairment and blindness higher up on the agenda. This article summarises the main points made in relation to retinal diseases, in particular the challenge of diabetic retinopathy.

  9. Blindness and visual impairment due to retinal diseases

    Directory of Open Access Journals (Sweden)

    Shaheen Shah

    2009-03-01

    Full Text Available This General Assembly, compared to others in the past, had retinal diseases as a cause of visual impairment and blindness higher up on the agenda. This article summarises the main points made in relation to retinal diseases, in particular the challenge of diabetic retinopathy.

  10. Retinal Glia Promote Dorsal Root Ganglion Axon Regeneration

    Science.gov (United States)

    Chong, Rachel S.; Fawcett, James W.; Martin, Keith R.

    2015-01-01

    Axon regeneration in the adult central nervous system (CNS) is limited by several factors including a lack of neurotrophic support. Recent studies have shown that glia from the adult rat CNS, specifically retinal astrocytes and Müller glia, can promote regeneration of retinal ganglion cell axons. In the present study we investigated whether retinal glia also exert a growth promoting effect outside the visual system. We found that retinal glial conditioned medium significantly enhanced neurite growth and branching of adult rat dorsal root ganglion neurons (DRG) in culture. Furthermore, transplantation of retinal glia significantly enhanced regeneration of DRG axons past the dorsal root entry zone after root crush in adult rats. To identify the factors that mediate the growth promoting effects of retinal glia, mass spectrometric analysis of retinal glial conditioned medium was performed. Apolipoprotein E and secreted protein acidic and rich in cysteine (SPARC) were found to be present in high abundance, a finding further confirmed by western blotting. Inhibition of Apolipoprotein E and SPARC significantly reduced the neuritogenic effects of retinal glial conditioned medium on DRG in culture, suggesting that Apolipoprotein E and SPARC are the major mediators of this regenerative response. PMID:25816134

  11. Retino-choroidal ischemia in central retinal vein occlusion

    OpenAIRE

    Hussain, Nazimul; Hussain, Anjli

    2014-01-01

    A 41-year-old gentleman with insulin dependent diabetes had decreased vision in the right eye due to non-ischemic central retinal vein occlusion with macular edema. One month following intravitreal ranibizumab, he developed retino-choroidal ischemia with further loss of vision. Authors show the fluorescein angiographic transition from non-ischemic central retinal vein occlusion to retino-choroidal ischemia.

  12. 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.

  13. 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…

  14. Bilateral acute retinal necrosis-A case report

    Directory of Open Access Journals (Sweden)

    Prasad Palimar

    1992-01-01

    Full Text Available A 42 year old man presented with acute bilateral uveitis and necrotizing retinitis. Systemic investigations including test for AIDS and CMV retinitis were negative. Despite oral Acyclovir, both eyes progressed rapidly to retinal detachment with loss of vision. Early recognition is necessary to diagnose the bilateral acute retinal necrosis syndrome and initiate treatment. Bilateral acute retinal necrosis (BARN is a term first coined by Young and Bird in 1978 although the syndrome had been originally described by Urayama et al as an unilateral condition. This syndrome is characterized by the triad of acute confluent peripheral necrotizing retinitis, moderate to severe vasculitis and vitritis in an otherwise healthy individual. Rhegmatogenous retinal detachment occurs within two to three months of the onset of the disease and the second eye is involved in 36% of patients, usually within 6 weeks. We herein report a patient who presented with simultaneous BARN leading to retinal detachment in a matter of days. Also, to our knowledge this is the first report of this condition in India.

  15. 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).

  16. Prolonged prevention of retinal degeneration with retinylamine loaded nanoparticles.

    Science.gov (United States)

    Puntel, Anthony; Maeda, Akiko; Golczak, Marcin; Gao, Song-Qi; Yu, Guanping; Palczewski, Krzysztof; Lu, Zheng-Rong

    2015-03-01

    Retinal degeneration impairs the vision of millions in all age groups worldwide. Increasing evidence suggests that the etiology of many retinal degenerative diseases is associated with impairment in biochemical reactions involved in the visual cycle, a metabolic pathway responsible for regeneration of the visual chromophore (11-cis-retinal). Inefficient clearance of toxic retinoid metabolites, especially all-trans-retinal, is considered responsible for photoreceptor cytotoxicity. Primary amines, including retinylamine, are effective in lowing the concentration of all-trans-retinal within the retina and thus prevent retina degeneration in mouse models of human retinopathies. Here we achieved prolonged prevention of retinal degeneration by controlled delivery of retinylamine to the eye from polylactic acid nanoparticles in Abca4(-/-)Rdh8(-/-) (DKO) mice, an animal model of Stargardt disease/age-related macular degeneration. Subcutaneous administration of the nanoparticles containing retinylamine provided a constant supply of the drug to the eye for about a week and resulted in effective prolonged prevention of light-induced retinal degeneration in DKO mice. Retinylamine nanoparticles hold promise for prolonged prophylactic treatment of human retinal degenerative diseases, including Stargardt disease and age-related macular degeneration. PMID:25617130

  17. Vitrectomy of rhegmatogenous retinal detachment in morning glory syndrome

    OpenAIRE

    Yang, Xiao-li; Zhang, Xi

    2010-01-01

    We report a case of retinal detachment in morning glory syndrome(MGS). We think that identification of the retinal break, removal of the traction force by vitrectomy, the use of long-acting gas as endotamponade, all contributed to the successful treatment of the disease. The pathogenic mechanisms of the disease and the function of B-scan to the diagnosis are included.

  18. 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.

  19. 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.

  20. 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.

  1. Validity of retinal oxygen saturation analysis: Hyperspectral imaging in visible wavelength with fundus camera and liquid crystal wavelength tunable filter

    Science.gov (United States)

    Hirohara, Yoko; Okawa, Yoshitaka; Mihashi, Toshifumi; Yamaguchi, Tatsuo; Nakazawa, Naoki; Tsuruga, Yasuko; Aoki, Hiroyuki; Maeda, Naoyuki; Uchida, Ichiro; Fujikado, Takashi

    2007-05-01

    The purpose of this paper was to investigate the feasibility of a newly developed hyperspectral fundus imaging camera with a liquid crystal tunable filter. The intensities of different wavelengths of light transmitted through an artery, vein, and the area surrounding these vessels and reflected out were measured, and the differential spectral absorptions were analyzed. Measurements were made from 16 normal eyes and from two artificial capillaries. The ratios of absorption (ROA) of arteries to veins from 500 to 580 nm (range 1) and from 600 to 720 nm (range 2) were calculated. For all eyes, the ROArange1 was larger than ROArange2. The ROA obtained from the artificial capillary filled with blood saturated with oxygen or nitrogen was similar to that of simulated data of oxy- and deoxyhemoglobin extinction rate. Most ROAs of human eyes were lower than those of the simulated data and the artificial capillaries. Oxygen saturation analysis by hyperspectral fundus imaging of retinal vessels were qualitatively in agreement with the in vitro analysis or simulated values. However, further improvements are necessary to evaluate the oxygen saturation quantitatively in the retinal blood vessels.

  2. Cdh23 mutations in the mouse are associated with retinal dysfunction but not retinal degeneration.

    Science.gov (United States)

    Libby, Richard T; Kitamoto, Junko; Holme, Ralph H; Williams, David S; Steel, Karen P

    2003-12-01

    Mutations in the cadherin 23 gene (CDH23) cause Usher syndrome type 1D in humans, a disease that results in retinitis pigmentosa and deafness. Cdh23 is also mutated in the waltzer mouse. In order to determine if the retina of the waltzer mouse undergoes retinal degeneration and to gain insight into the function of cadherin 23 in the retina, we have characterized the anatomy and physiology of retinas of waltzer mouse mutants. Three mutant alleles of Cdh23 were examined by histology and electroretinography (ERG). ERGs of the three Cdh23 mutant groups revealed two of them to have abnormal retinal function. One allele had a- and b-waves that were only approximately 80% of Cdh23 heterozygotes. Another allele had a significantly faster implicit time for both the a- and b-waves of the ERG. No anatomical abnormality was detected in any of the Cdh23 mutants by light microscopy. Because the mutant Cdh23 phenotype was found to be similar to the previously reported retinal phenotype of Myo7a mutant mice, the orthologue of another Usher syndrome (type 1B) gene, we generated mice that carried mutations in both genes to test for genetic interaction in the retina. No functional interaction between cadherin 23 and myosin VIIa was detected by either microscopy or ERG. PMID:14609561

  3. Twist Buckling Behavior of Arteries

    OpenAIRE

    Garcia, Justin R.; Lamm, Shawn D.; Han, Hai-chao

    2012-01-01

    Arteries are often subjected to torsion due to body movement and surgical procedures. While it is essential that arteries remain stable and patent under twisting loads, the stability of arteries under torsion is poorly understood. The goal of this work was to experimentally investigate the buckling behavior of arteries under torsion and to determine the critical buckling torque, the critical buckling twist angle, and the buckling shape. Porcine common carotid arteries were slowly twisted in v...

  4. Cytomegalovirus retinitis complicating combination therapy with rituximab and fludarabine.

    Science.gov (United States)

    Chan, Thomas S Y; Cheung, Carol Y M; Yeung, Ian Y L; Hwang, Yu-Yan; Gill, Harinder; Wong, Ian Y; Kwong, Yok-Lam

    2015-06-01

    Cytomegalovirus (CMV) retinitis is exceptionally rare outside the clinical context of acquired immunodeficiency syndrome and organ allografting. In a population where seropositivity for past CMV infection exceeded 90 %, CMV retinitis was observed in five of 138 patients (3.6 %) receiving fludarabine-containing regimens together with rituximab, which was significantly more frequent than in 141 patients receiving fludarabine-containing regimens alone, where no case was observed (P?=?0.029). Treatment of CMV retinitis comprised both intravitreal and systemic ganciclovir/foscarnet. Upon recovery, secondary retinal atrophy occurred in all patients, leading to blindness in 86 % of affected eyes. CMV retinitis is an important complication in patients receiving concomitant rituximab and fludarabine-containing regimens. PMID:25572171

  5. Optical model of the blood in large retinal vessels

    Science.gov (United States)

    Denninghoff, Kurt R.; Smith, Matthew H.

    2000-10-01

    Several optical techniques that investigate blood contained within the retinal vessels are available or under development. We present a mechanical model that simulates the optical properties of the eye, the retinal vessels, and the ocular fundus. A micropipette is chosen as the retinal vessel model, and a mechanical housing is constructed to simulate the eyeball. Spectralon is used to simulate the retinal layers. Filling the eye with fluid index matched to the glass pipette eliminates reflection and refraction effects from the pipette. An apparatus is constructed and used to set the oxygen, nitrogen, and carbon dioxide concentrations in whole human blood. These whole blood samples are pumped through the pipette at 34 (mu) L/min. Measurements made in the model eye closely resemble measurements made in the human eye. This apparatus is useful for developing the science and testing the systems that optically investigate blood and blood flow in the large retinal vessels.

  6. Vertebrobasilar Artery Occlusion

    OpenAIRE

    Schoen, Jessica; Boysen, Megan; Warren, Chase; Chakravarthy, Bharath; Lotfipour, Shahram MD, MPH

    2011-01-01

    The presentation of vertebrobasilar artery occlusion varies with the cause of occlusion and location of ischemia. This often results in delay in diagnosis. Areas of the brain supplied by the posterior circulation are difficult to visualize and usually require angiography or magnetic resonance imaging. Intravenous thrombolysis and local-intra arterial thrombolysis are the most common treatment approaches used. Recanalization of the occluded vessel significantly improves morbidity and mortality...

  7. ATP-induced relaxation of porcine retinal arterioles in vitro depends on prostaglandin E synthesized in the perivascular retinal tissue

    DEFF Research Database (Denmark)

    Holmgaard, Kim; Bek, Toke

    2010-01-01

    It has been shown that inhibition of prostaglandin synthesis in the perivascular retinal tissue can prevent the relaxation of retinal arterioles induced by N-methyl-d-aspartic acid (NMDA) and adenosine triphosphate (ATP). The purpose of the present study was to identify the prostaglandins involved in this retina-dependent relaxation.

  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. Developing cellular therapies for retinal degenerative diseases.

    Science.gov (United States)

    Bharti, Kapil; Rao, Mahendra; Hull, Sara Chandros; Stroncek, David; Brooks, Brian P; Feigal, Ellen; van Meurs, Jan C; Huang, Christene A; Miller, Sheldon S

    2014-02-01

    Biomedical advances in vision research have been greatly facilitated by the clinical accessibility of the visual system, its ease of experimental manipulation, and its ability to be functionally monitored in real time with noninvasive imaging techniques at the level of single cells and with quantitative end-point measures. A recent example is the development of stem cell-based therapies for degenerative eye diseases including AMD. Two phase I clinical trials using embryonic stem cell-derived RPE are already underway and several others using both pluripotent and multipotent adult stem cells are in earlier stages of development. These clinical trials will use a variety of cell types, including embryonic or induced pluripotent stem cell-derived RPE, bone marrow- or umbilical cord-derived mesenchymal stem cells, fetal neural or retinal progenitor cells, and adult RPE stem cells-derived RPE. Although quite distinct, these approaches, share common principles, concerns and issues across the clinical development pipeline. These considerations were a central part of the discussions at a recent National Eye Institute meeting on the development of cellular therapies for retinal degenerative disease. At this meeting, emphasis was placed on the general value of identifying and sharing information in the so-called "precompetitive space." The utility of this behavior was described in terms of how it could allow us to remove road blocks in the clinical development pipeline, and more efficiently and economically move stem cell-based therapies for retinal degenerative diseases toward the clinic. Many of the ocular stem cell approaches we discuss are also being used more broadly, for nonocular conditions and therefore the model we develop here, using the precompetitive space, should benefit the entire scientific community. PMID:24573369

  10. Unusual origin of the left vertebral artery

    OpenAIRE

    Imre N; Yalcin B; Ozan H

    2010-01-01

    The vertebral artery is important to posterior cerebral circulation. Several researchers have reported anomalous origins of the vertebral artery such as from the aortic arch, between the left common carotid artery and left subclavian artery or after left subclavian artery, from the thyrocervical trunk, from the brachiocephalic trunk, from the common carotid artery, from the external carotid artery, from a common carotid trunk formed by left subclavian artery and left vertebral artery. We enco...

  11. Color Doppler evaluation of the ocular arterial flow changes in chronic obstructive pulmonary disease

    International Nuclear Information System (INIS)

    Purpose: To evaluate the hemodynamic changes in the extraocular orbital vessels of the patients with chronic obstructive pulmonary disease (COPD), using color Doppler ultrasonography (CDU) technique, and to compare the results with those of healthy control subjects. Methods: Forty-five patients with COPD and 17 healthy control subjects were included in this study. Patients with COPD were classified according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD). Fifteen patients of stage I COPD (mild airflow limitation), stage II COPD (worsening airflow limitation) or stage III COPD (severe airflow limitation) were enrolled into Group I, II and III, respectively. End tidal carbon dioxide (EtCO2), peripheral oxygen saturation (SpO2), pulse rate (PR) and respiratory rate (RR) were measured by using capnograph/pulse oximeter in all patients. Measurements were performed in only one randomly chosen eye of each participant. The peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistance index (RI) were measured in the ophthalmic artery (OA), central retinal artery (CRA), lateral short posterior ciliary artery (LPCA) and medial short posterior ciliary artery (MPCA), using CDU technique. Results: The PSV measurements of the OA were significantly higher in Groups II and III compared to control group (p 2 with PSV (r = 0.53, p < 0.01) and EDV (r = 0.51, p < 0.01) of the OA. Statistically significant correlations were also found for the SpO2 with RI (r = -0.34, p < 0.05) in the OA. Conclusion: We concluded that COPD is associated with impaired retrobulbar hemodynamics, especially in the ophthalmic artery. Moreover, central retinal and posterior ciliary arteries with increased resistance are also found to be affected when compared with healthy control eyes

  12. Intravitreous Delivery of the Corticosteroid Fluocinolone Acetonide Attenuates Retinal Degeneration in S334ter-4 Rats

    OpenAIRE

    Glybina, Inna V.; Kennedy, Alexander; Ashton, Paul; Abrams, Gary W.; Iezzi, Raymond

    2010-01-01

    Retinal neuroinflammation has been identified in association with a number of retinal degenerative diseases, including retinitis pigmentosa and age-related macular degeneration. Low-dose intravitreal sustained-release fluocinolone acetonide dampened retinal neuroinflammation and was associated with preservation of photoreceptors and electroretinographic amplitudes in S334ter-4 rats.

  13. Interferon-induced central retinal vein thrombosis

    International Nuclear Information System (INIS)

    A middle-aged lady presented with sudden onset of unilateral central retinal vein thrombosis after completing 6 months course of interferon and ribavirin for chronic hepatitis C infection. She had no risk factors and all her thrombophilia workup was normal, however, she was found to be dyslipidemic which may have contributed to atherosclerosis and predispose to thrombosis. Despite anticoagulation, her visual acuity deteriorated. This case illustrates the possibility of unpredictable visual complication of interferon. Frequent eye examination should be undertaken in patients having underlying risk factors like diabetes, hypertension or dyslipidemia undergoing interferon therapy. (author)

  14. The Workings of the Retinal Prosthesis

    Science.gov (United States)

    This YouTube video, created by Southwest Center for Microsystems Education (SCME), describes a biomedical application of MEMS technology. This 5:08 minute long video describes "how a microsystems array is used in the retinal prosthesis to stimulate cells in the retina that talk to the brain via the optic nerve." Diagrams of the prosthesis, as well as the retina, and descriptions of how resolution can be increased are included. Viewers can learn more about this topic on the SCME website.

  15. [Rhegmatogenous retinal detachment--clinical case].

    Science.gov (United States)

    Mu?at, O; Cristescu, R; Ochinciuc, Uliana; Gu?u, Tatiana; Coman, Corina; Asandi, R

    2011-01-01

    We present the case of a 57 years old woman which was admitted for the amputation of the infero-nasal visual field of the right eye, change observed by the pacient for 2 weeks. Clinical examination and lab exams revealed the cause of this change: a rhegmatogenous retinal detachment in the superior temporal quadrant. Surgical treatement was warranted. We did a posterior vitrectomy with trans-scleral crioapplications and injection of silicone oil 1000. We followed the patient's evolution post-operative and we observed the development of a complicated cataract which was treated in a second surgery together with the extraction of the silicone oil. The evolution was favorable. PMID:22642139

  16. 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

  17. Histogenesis of retinal dysplasia in trisomy 13

    Directory of Open Access Journals (Sweden)

    Gonzalez-Fernandez Federico

    2007-12-01

    Full Text Available Abstract Background Although often associated with holoprosencephaly, little detail of the histopathology of cyclopia is available. Here, we describe the ocular findings in a case of trisomy 13 to better understand the histogenesis of the rosettes, or tubules, characteristic of the retinal dysplasia associated with this condition. Methods A full pediatric autopsy was performed of a near term infant who died shortly after birth from multiple congenital anomalies including fused facial-midline structures. A detailed histopathological study of the ocular structures was performed. The expression of interphotoreceptor retinoid-binding protein (IRBP, cellular retinal-binding protein (CRALBP, rod opsin, and Sonic Hedgehog (Shh were studied by immunohistochemistry. Results Holoprosencephaly, and a spectrum of anatomical findings characteristic of Patau's syndrome, were found. Cytogenetic studies demonstrated trisomy 13 [47, XY, +13]. The eyes were fused but contained two developed separate lenses. In contrast, the cornea, and angle structures were hypoplastic, and the anterior chamber had failed to form. The retina showed areas of normally laminated neural retina, whereas in other areas it was replaced by numerous neuronal rosettes. Histological and immunohistochemical studies revealed that the rosettes were composed of differentiated retinal neurons and Müller cell glia. In normally laminated retina, Shh expression was restricted to retinal-ganglion cells, and to a population of neurons in the inner zone of the outer nuclear layer. In contrast, Shh could not be detected in the dysplastic rosettes. Conclusion The histopathology of cyclopia appears to be more complex than what may have been previously appreciated. In fact, the terms "cyclopia" and "synophthalmia" are misnomers as the underlying mechanism is a failure of the eyes to form separately during development. The rosettes found in the dysplastic retina are fundamentally different than those of retinoblastoma, being composed of a variety of differentiated cell types. The dysplastic rosettes are essentially laminated retina failing to establish a polarized orientation, resulting in the formation of tubules. Finally, our findings suggest that defective ganglion cell Shh expression may contribute to the ocular pathology of cyclopia.

  18. Coronary Artery and Pulmonary Artery Fistula Originated from Significant Stenosis in the Left Anterior Descending Artery

    OpenAIRE

    Alper Sami Kunt

    2013-01-01

    Coronary artery fistula (CAF) is defined as a rare anomalous connection between a coronary artery and a major vessel or a cardiac chamber. We report a case of a left anterior descending coronary (LAD) stenosis and coronary artery fistula between the LAD coronary artery and the pulmonary artery (PA). CAF is often diagnosed by coronary angiogram. We describe our diagnostic approach and review the literature on the epidemiology, the pathophysiology, the diagnostic modalities, and the treatment o...

  19. Peripheral and central arterial pressure and its relationship to vascular target organ damage in carotid artery, retina and arterial stiffness. Development and validation of a tool. The Vaso risk study

    Directory of Open Access Journals (Sweden)

    Patino-Alonso Maria C

    2011-04-01

    Full Text Available Abstract Background Ambulatory blood pressure monitoring (ABPM shows a better correlation to target organ damage and cardiovascular morbidity-mortality than office blood pressure. A loss of arterial elasticity and an increase in carotid artery intima-media thickness (IMT has been associated with increased cardiovascular morbidity-mortality. Tools have been developed that allow estimation of the retinal arteriovenous index but not all studies coincide and there are contradictory results in relation to the evolution of the arteriosclerotic lesions and the caliber of the retinal vessels. The purpose of this study is to analyze the relationship between peripheral and central arterial pressure (clinic and ambulatory and vascular structure and function as evaluated by the carotid artery intima-media thickness, retina arteriovenous index, pulse wave velocity (PWV and ankle-brachial index in patients with and without type 2 diabetes. In turn, software is developed and validated for measuring retinal vessel thickness and automatically estimating the arteriovenous index. Methods/Design A cross-sectional study involving a control group will be made, with a posterior 4-year follow-up period in primary care. The study patients will be type 2 diabetics, with a control group of non-diabetic individuals. Consecutive sampling will be used to include 300 patients between 34-75 years of age and no previous cardiovascular disease, one-half being assigned to each group. Main measurements: age, gender, height, weight and abdominal circumference. Lipids, creatinine, microalbuminuria, blood glucose, HbA1c, blood insulin, high sensitivity C-reactive protein and endothelial dysfunction markers. Clinic and ambulatory blood pressure monitoring. Carotid ultrasound to evaluate IMT, and retinography to evaluate the arteriovenous index. ECG to assess left ventricle hypertrophy, ankle-brachial index, and pulse wave analysis (PWA and pulse wave velocity (PWV with the Sphigmocor System. Discussion We hope to obtain information on the correlation of different ABPM-derived parameters and PWA to organ target damage - particularly vascular structure and function evaluated from the IMT and PWV - and endothelial dysfunction in patients with and without type 2 diabetes. We also hope to demonstrate the usefulness of the instrument developed for the automated evaluation of retinal vascularization in the early detection of alterations in vascular structure and function and in the prognosis of middle-term cardiovascular morbidity. Trial Registration Clinical Trials.gov Identifier: NCT01325064

  20. The newt reprograms mature RPE cells into a unique multipotent state for retinal regeneration

    OpenAIRE

    Md. Rafiqul Islam; Kenta Nakamura; Martin Miguel Casco-Robles; Ailidana Kunahong; Wataru Inami; Fubito Toyama; Fumiaki Maruo; Chikafumi Chiba

    2014-01-01

    The reprogramming of retinal pigment epithelium (RPE) cells in the adult newt immediately after retinal injury is an area of active research for the study of retinal disorders and regeneration. We demonstrate here that unlike embryonic/larval retinal regeneration, adult newt RPE cells are not directly reprogrammed into retinal stem/progenitor cells; instead, they are programmed into a unique state of multipotency that is similar to the early optic vesicle (embryo) but preserves certain adult ...

  1. GABAergic neurotransmission and retinal ganglion cell function.

    Science.gov (United States)

    Popova, E

    2015-03-01

    Ganglion cells are the output retinal neurons that convey visual information to the brain. There are ~20 different types of ganglion cells, each encoding a specific aspect of the visual scene as spatial and temporal contrast, orientation, direction of movement, presence of looming stimuli; etc. Ganglion cell functioning depends on the intrinsic properties of ganglion cell's membrane as well as on the excitatory and inhibitory inputs that these cells receive from other retinal neurons. GABA is one of the most abundant inhibitory neurotransmitters in the retina. How it modulates the activity of different types of ganglion cells and what is its significance in extracting the basic features from visual scene are questions with fundamental importance in visual neuroscience. The present review summarizes current data concerning the types of membrane receptors that mediate GABA action in proximal retina; the effects of GABA and its antagonists on the ganglion cell light-evoked postsynaptic potentials and spike discharges; the action of GABAergic agents on centre-surround organization of the receptive fields and feature related ganglion cell activity. Special emphasis is put on the GABA action regarding the ON-OFF and sustained-transient ganglion cell dichotomy in both nonmammalian and mammalian retina. PMID:25656810

  2. Retinal vasoproliferative tumor / Tumor vasoproliferativo da retina

    Scientific Electronic Library Online (English)

    Eduardo Ferrari, Marback; Ricardo Leitão, Guerra; Otacilio de Oliveira, Maia Junior; Roberto Lorens, Marback.

    2013-06-01

    Full Text Available O tumor vasoproliferativo da retina é uma lesão rara, cujo principal diagnóstico diferencial é o hemangioma capilar da retina. O tumor tem natureza reacional. Pode ser idiopático ou secundário a outras doenças como: uveítes, retinose pigmentar, retinopatia da anemia falciforme, cirurgia prévia e ret [...] inopatia da prematuridade. Lesões sem exsudação ou baixa visual podem ser observadas. Quando há indicação de tratamento este pode ser feito pela crioterapia, vários tipos de lasers, excisão cirúrgica, radioterapia e injeções intravítrea de antiangiogênicos, isoladamente ou em associação. Abstract in english 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, previo [...] us 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.

  3. Urocortin 2 treatment is protective in excitotoxic retinal degeneration.

    Science.gov (United States)

    Szabadfi, K; Kiss, P; Reglodi, D; Fekete, E M; Tamas, A; Danyadi, B; Atlasz, T; Gabriel, R

    2014-03-01

    Urocortin 2 (Ucn 2) is a corticotrop releasing factor paralog peptide with many physiological functions and it has widespread distribution. There are some data on the cytoprotective effects of Ucn 2, but less is known about its neuro- and retinoprotective actions. We have previously shown that Ucn 2 is protective in ischemia-induced retinal degeneration. The aim of the present study was to examine the protective potential of Ucn 2 in monosodium-glutamate (MSG)-induced retinal degeneration by routine histology and to investigate cell-type specific effects by immunohistochemistry. Rat pups received MSG applied on postnatal days 1, 5 and 9 and Ucn 2 was injected intravitreally into one eye. Retinas were processed for histology and immunocytochemistry after 3 weeks. Immunolabeling was determined for glial fibrillary acidic protein, vesicular glutamate transporter 1, protein kinase C?, calbindin, parvalbumin and calretinin. Retinal tissue from animals treated with MSG showed severe degeneration compared to normal retinas, but intravitreal Ucn 2 treatment resulted in a retained retinal structure both at histological and neurochemical levels: distinct inner retinal layers and rescued inner retinal cells (different types of amacrine and rod bipolar cells) could be observed. These findings support the neuroprotective function of Ucn 2 in MSG-induced retinal degeneration. PMID:24311224

  4. Retinal Image Analysis for Abnormality Detection-An Overview

    Directory of Open Access Journals (Sweden)

    R. Karthikeyan

    2012-01-01

    Full Text Available Problem statement: Classification plays a major role in retinal image analysis for detecting the various abnormalities in retinal images. Classification refers to one of the mining concepts using supervised or unsupervised learning techniques. Approach: Diabetic retinopathy is one of the common complications of diabetes. Unfortunately, in many cases, the patient is not aware of any symptoms until it is too late for effective treatment. Diabetic retinopathy is the leading cause of blindness. Diabetic retinopathy results in retinal disorders that include microaneursyms, drusens, hard exudates and intra-retinal micro-vascular abnormalities. Results: Automatic methods to detect various lesions associated with diabetic retinopathy facilitate the opthalmologists in accurate diagnosis and treatment planning. Abnormal retinal images fall into four different classes namely Non-Proliferative Diabetic Retinopathy (NPDR, Central Retinal Vein Occlusion (CRVO, Choroidal Neo-Vascularization Membrane (CNVM and Central Serous Retinopathy (CSR.. Conclusion: In this study, we have analysed the various methodologies for detecting the abnormalities in retinal images automatically along with their merits and demerits and proposed the new framework for detection of abnormalities using Cellular Neural Network (CNN.

  5. Rapid glutamate receptor 2 trafficking during retinal degeneration

    Directory of Open Access Journals (Sweden)

    Lin Yanhua

    2012-02-01

    Full Text Available Abstract Background Retinal degenerations, such as age-related macular degeneration (AMD and retinitis pigmentosa (RP, are characterized by photoreceptor loss and anomalous remodeling of the surviving retina that corrupts visual processing and poses a barrier to late-stage therapeutic interventions in particular. However, the molecular events associated with retinal remodeling remain largely unknown. Given our prior evidence of ionotropic glutamate receptor (iGluR reprogramming in retinal degenerations, we hypothesized that the edited glutamate receptor 2 (GluR2 subunit and its trafficking may be modulated in retinal degenerations. Results Adult albino Balb/C mice were exposed to intense light for 24 h to induce light-induced retinal degeneration (LIRD. We found that prior to the onset of photoreceptor loss, protein levels of GluR2 and related trafficking proteins, including glutamate receptor-interacting protein 1 (GRIP1 and postsynaptic density protein 95 (PSD-95, were rapidly increased. LIRD triggered neuritogenesis in photoreceptor survival regions, where GluR2 and its trafficking proteins were expressed in the anomalous dendrites. Immunoprecipitation analysis showed interaction between KIF3A and GRIP1 as well as PSD-95, suggesting that KIF3A may mediate transport of GluR2 and its trafficking proteins to the novel dendrites. However, in areas of photoreceptor loss, GluR2 along with its trafficking proteins nearly vanished in retracted retinal neurites. Conclusions All together, LIRD rapidly triggers GluR2 plasticity, which is a potential mechanism behind functionally phenotypic revisions of retinal neurons and neuritogenesis during retinal degenerations.

  6. Hipertensión arterial: Aspectos fisiopatológicos

    Directory of Open Access Journals (Sweden)

    Alfredo Vázquez Vigoa

    1996-12-01

    Full Text Available Se revisaron los aspectos fisiopatológicos que intervienen en la génesis de la enfermedad hipertensiva para actualizar los conocimientos en relación con los mecanismos que generan la hipertensión arterial. Se hizo hincapié en el aumento de la resistencia periférica, los trastornos de excreción del sodio y las alteraciones del transporte de sodio a través de la membrana. Comentamos además las nuevas teorías sobre recientes sustancias vasoactivas capaces de incrementar el tono vascular, como la endotelina, y relacionamos los sistemas locales o autocrinos de renina/angiotensina/aldosterona con la hipertensión arterial. Se concluye que sobre el sustrato o fondo poligénico de la hipertensión se superponen alteraciones humorales capaces de perpetuar la elevación de la presión arterial.The physiopathological aspects involved in the genesis of the hypertensive disease were revised in order to up-date the understanding regarding the mechanisms which generate high blood pressure. Emphasis was made in the increased peripheral resistance, the disorders of sodium excretion and on alterations regarding the sodium transport through the membrane. In addition, new theories about certain vasoactive substances recently found, capable of increasing the vascular tone such as endotelin, are also pointed out. Local or self endocrine systems of renin/angiotensin/aldosterone were found to be related to arterial hypertension. The authors concluded that certain humoral alterations capable of perpetuating the elevated arterial pressure are superimposed over the polygenic sustrate of hypertension.

  7. Brachial Artery Access for Percutaneous Renal Artery Interventions

    International Nuclear Information System (INIS)

    Purpose: To evaluate the suitability of transbrachial access for endovascular renal artery interventions. Methods: During 37 consecutive endovascular renal artery interventions, the transbrachial approach was used on nine patients (mean age 63 years; range 41-76 years) for 11 renal artery procedures on native kidneys and one percutaneous transluminal angioplasty (PTA) on a transplanted kidney. The reason for using transbrachial access was a steep aorta-renal angle in five, and severe aorta-iliac atherosclerosis in the remaining patients. In addition to the intervention catheter in the left brachial artery, an additional nonselective catheter for controlling the procedure was inserted transfemorally (six patients) or via the contralateral brachial artery. Results: Eleven interventions (six PTAs, five stents) were successfully completed. The one failure resulted from impenetrable subclavian artery stenosis. The only major complication was a brachial artery pseudoaneurysm requiring surgical treatment. Conclusion: Transbrachial access is an effective and relatively safe technique for renal artery interventions when transfemoral access is not possible

  8. Coronary artery disease in Alström syndrome.

    Science.gov (United States)

    Jatti, Kumar; Paisey, Richard; More, Ranjit

    2012-01-01

    Alström syndrome (ALMS) is a rare autosomal recessive condition, caused by mutations in the ALMS1 gene located on the short arm of chromosome 2. This gene codes for a protein linked with the centrosome, whose precise function is unknown. This condition was first described by Alström in 1959. ALMS is a multisystem condition that is characterised by childhood onset of blindness secondary to rod-cone retinal degeneration and dilated cardiomyopathy with heart failure, which often presents in infanthood and may recur later in life. Metabolic abnormalities including hypertriglyceridemia, liver steatosis, insulin resistance and type 2 diabetes mellitus are common, often occurring in association with obesity. Other abnormalities include endocrinological disturbances, such as thyroid disorder, growth hormone deficiency, hypogonadism and, in women, hyperandrogenism. This syndrome is also associated with sensorineural hearing loss, renal failure secondary to glomerulo-fibrosis, and fibrotic lung disease. Multiorgan fibrotic infiltration is the common feature in all cases. Considering the history of diabetes, hypertension, dyslipidemia, obesity and renal dysfunction in ALMS, it would be expected that this group of patients could develop coronary artery disease (CAD). But such cases have not been reported so far. We report a case of premature onset of CAD in one of the longest surviving patient with ALMS. PMID:21897446

  9. Two-photon in vivo imaging of retinal microstructures

    Science.gov (United States)

    Schejter, Adi; Farah, Nairouz; Shoham, Shy

    2014-02-01

    Non-invasive fluorescence retinal imaging in small animals is an important requirement in an array of translational vision applications. Two-photon imaging has the potential for long-term investigation of healthy and diseased retinal function and structure in vivo. Here, we demonstrate that two-photon microscopy through a mouse's pupil can yield high-quality optically sectioned fundus images. By remotely scanning using an electronically tunable lens we acquire highly-resolved 3D fluorescein angiograms. These results provide an important step towards various applications that will benefit from the use of infrared light, including functional imaging of retinal responses to light stimulation.

  10. Perfusion of occluded retinal veins in the cat's eye.

    OpenAIRE

    Zauberman, H.; Levinger, S.; Burde, R. M.

    1984-01-01

    The organisation and adherence of a clot induced experimentally in the retinal vein of a cat was studied in vitro. For this purpose a retinal vein was treated in vivo with argon laser photocoagulation in 31 eyes, and each eye was removed at periods of time varying between 3 hours and 7 days after treatment. The freshly enucleated eye was then placed in a perfusion chamber with the cornea under a contact lens, and the retinal vessels were perfused under direct microscopic visualisation. It app...

  11. Current focus of stem cell application in retinal repair

    OpenAIRE

    Alonso-Alonso, María L; Girish K. Srivastava

    2015-01-01

    The relevance of retinal diseases, both in society’s economy and in the quality of people’s life who suffer with them, has made stem cell therapy an interesting topic for research. Embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs) and adipose derived mesenchymal stem cells (ADMSCs) are the focus in current endeavors as a source of different retinal cells, such as photoreceptors and retinal pigment epithelial cells. The aim is to apply them for cell replacement as an option f...

  12. Overexpression of Pax6 results in microphthalmia, retinal dysplasia and defective retinal ganglion cell axon guidance

    Directory of Open Access Journals (Sweden)

    Jeffery Glen

    2008-05-01

    Full Text Available Abstract Background The transcription factor Pax6 is expressed by many cell types in the developing eye. Eyes do not form in homozygous loss-of-function mouse mutants (Pax6Sey/Sey and are abnormally small in Pax6Sey/+ mutants. Eyes are also abnormally small in PAX77 mice expressing multiple copies of human PAX6 in addition to endogenous Pax6; protein sequences are identical in the two species. The developmental events that lead to microphthalmia in PAX77 mice are not well-characterised, so it is not clear whether over- and under-expression of Pax6/PAX6 cause microphthalmia through similar mechanisms. Here, we examined the consequences of over-expression for the eye and its axonal connections. Results Eyes form in PAX77+/+ embryos but subsequently degenerate. At E12.5, we found no abnormalities in ocular morphology, retinal cell cycle parameters and the incidence of retinal cell death. From E14.5 on, we observed malformations of the optic disc. From E16.5 into postnatal life there is progressively more severe retinal dysplasia and microphthalmia. Analyses of patterns of gene expression indicated that PAX77+/+ retinae produce a normal range of cell types, including retinal ganglion cells (RGCs. At E14.5 and E16.5, quantitative RT-PCR with probes for a range of molecules associated with retinal development showed only one significant change: a slight reduction in levels of mRNA encoding the secreted morphogen Shh at E16.5. At E16.5, tract-tracing with carbocyanine dyes in PAX77+/+ embryos revealed errors in intraretinal navigation by RGC axons, a decrease in the number of RGC axons reaching the thalamus and an increase in the proportion of ipsilateral projections among those RGC axons that do reach the thalamus. A survey of embryos with different Pax6/PAX6 gene dosage (Pax6Sey/+, Pax6+/+, PAX77+ and PAX77+/+ showed that (1 the total number of RGC axons projected by the retina and (2 the proportions that are sorted into the ipsilateral and contralateral optic tracts at the optic chiasm vary differently with gene dosage. Increasing dosage increases the proportion projecting ipsilaterally regardless of the size of the total projection. Conclusion Pax6 overexpression does not obviously impair the initial formation of the eye and its major cell-types but prevents normal development of the retina from about E14.5, leading eventually to severe retinal degeneration in postnatal life. This sequence is different to that underlying microphthalmia in Pax6+/- heterozygotes, which is due primarily to defects in the initial stages of lens formation. Before the onset of severe retinal dysplasia, Pax6 overexpression causes defects of retinal axons, preventing their normal growth and navigation through the optic chiasm.

  13. 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

    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 age (P=0.41, 0.053, 0.29 for groups III-V, respectively). CONCLUSION: Studies on autoregulation in retinal disease should consider the normal age-related decrease in diameter response of retinal arterioles when the blood pressure is changed.

  14. 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

    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, while immunofluorescence staining was higher after ischemia in the neuroretina. HIF-1? immunoreactivity and mRNA expression were unaffected. VEGF protein levels in the vitreous humor and VEGF staining in the neuroretina were more pronounced in eyes subjected to ischemia than in the sham eyes. VEGF may be activated downstream of HIF-1 and is known to stimulate retinal neovascularization, which causes sight-threatening complications. These results emphasize the need for pharmacological treatment to block the HIF and VEGF signaling pathways in retinal ischemia.

  15. Hipertensión e hipotensión arterial

    Directory of Open Access Journals (Sweden)

    Carlos J. Mucha

    2007-07-01

    Full Text Available Si bien la hipertensión arterial (HTA, permanece como una de las causas más comunes de morbi-mortalidad en Medicina Humana, en la práctica Veterinaria todavía nos encontramos en las primeras etapas de diagnóstico y comprensión de la misma, debido a que la determinación de la presión arterial (PA no forma aun parte de la practica diaria y además no existen registros de parámetros normales en pequeños animales, de acuerdo a raza, sexo y edad lo que nos ayudaría a la mejor identificación del problema. De aquí el peligro de colocar el rotulo de hipertenso a un paciente, con solo la determinación de la PA, teniendo en cuenta además que la mayoría de los casos de HTA en Veterinaria, son secundarios a enfermedadessistémicas. Con respecto a la hipotensión arterial, los valores están más claros y su determinación es de fundamental importancia sobre todo en emergencias, pacientes en estado crítico y anestesia.

  16. Hepatic arterial collaterals in Ivalon embolization of hepatic artery

    International Nuclear Information System (INIS)

    Hepatic arterial collaterals after embolization of hepatic artery using Ivalon particles were evaluated with roentgenologic and pathologic procedures. The perivascular collaterals we observed that develop after peripheral occulsion of hepatic arteries with Ivalon probably represent perivascular arterioles or capillary networks that become enlarged. (author)

  17. Left Anterior Descending Artery-Pulmonary Artery Fistula

    Directory of Open Access Journals (Sweden)

    Turan Ege

    2011-12-01

    Full Text Available Despite the fact that coronary arteriovenous fistulas constitute approximately half (48% of coronary artery anomalies, they are rarely seen anomalies. In this report,we aim to present a coronary arteriovenous fistula case detected during a coronary angiography between left anterior descending artery and pulmonary artery.

  18. Carbonic anhydrase inhibition increases retinal oxygen tension and dilates retinal vessels

    DEFF Research Database (Denmark)

    Pedersen, Daniella Bach; Koch Jensen, Peter

    2005-01-01

    Carbonic anhydrase inhibitors (CAIs) increase blood flow in the brain and probably also in the optic nerve and retina. Additionally they elevate the oxygen tension in the optic nerve in the pig. We propose that they also raise the oxygen tension in the retina. We studied the oxygen tension in the pig retina and optic nerve before and after dorzolamide injection. Also the retinal vessel diameters during carbonic anhydrase inhibition were studied.

  19. Local signaling from a retinal prosthetic in a rodent retinitis pigmentosa model in vivo

    Science.gov (United States)

    Fransen, James W.; Pangeni, Gobinda; Pardue, Machelle T.; McCall, Maureen A.

    2014-08-01

    Objective. In clinical trials, retinitis pigmentosa patients implanted with a retinal prosthetic device show enhanced spatial vision, including the ability to read large text and navigate. New prosthetics aim to increase spatial resolution by decreasing pixel/electrode size and limiting current spread. To examine spatial resolution of a new prosthetic design, we characterized and compared two photovoltaic array (PVA) designs and their interaction with the retina after subretinal implantation in transgenic S334ter line 3 rats (Tg S334ter-3). Approach. PVAs were implanted subretinally at two stages of degeneration and assessed in vivo using extracellular recordings in the superior colliculus (SC). Several aspects of this interaction were evaluated by varying duration, irradiance and position of a near infrared laser focused on the PVA. These characteristics included: activation threshold, response linearity, SC signal topography and spatial localization. The major design difference between the two PVA designs is the inclusion of local current returns in the newer design. Main results. When tested in vivo, PVA-evoked response thresholds were independent of pixel/electrode size, but differ between the new and old PVA designs. Response thresholds were independent of implantation age and duration (?7.5 months). For both prosthesis designs, threshold intensities were within established safety limits. PVA-evoked responses require inner retina synaptic transmission and do not directly activate retinal ganglion cells. The new PVA design evokes local retinal activation, which is not found with the older PVA design that lacks local current returns. Significance. Our study provides in vivo evidence that prosthetics make functional contacts with the inner nuclear layer at several stages of degeneration. The new PVA design enhances local activation within the retina and SC. Together these results predict that the new design can potentially harness the inherent processing within the retina and is likely to produce higher spatial resolution in patients.

  20. Retinal Dystrophy Resulting from Ablation of RXR? in the Mouse Retinal Pigment Epithelium

    OpenAIRE

    Mori, Mikiro; Metzger, Daniel; Picaud, Serge; Hindelang, Colette; Simonutti, Manuel; Sahel, Jose?; Chambon, Pierre; Mark, Manuel

    2004-01-01

    Vitamin A (retinol) actions in eye development are mediated by retinoic acid receptors (RARs and RXRs). Using the Cre/loxP system, we have selectively ablated RXR? in the retinal pigment epithelium (RPE), a cell monolayer critically involved in visual retinoid renewal and phagocytosis of photoreceptor outer segments. In the mutant (RXR? rpe?/?) mice, RPE cells are morphologically and functionally abnormal and display decreased expression of proteins involved in the visual retinoid cycle...

  1. Retinal degeneration triggered by inactivation of PTEN in the retinal pigment epithelium

    OpenAIRE

    Kim, Jin Woo; Kang, Kyung Hwa; Burrola, Patrick; Mak, Tak W.; Lemke, Greg

    2008-01-01

    Adhesion between epithelial cells mediates apical–basal polarization, cell proliferation, and survival, and defects in adhesion junctions are associated with abnormalities from degeneration to cancer. We found that the maintenance of specialized adhesions between cells of the retinal pigment epithelium (RPE) requires the phosphatase PTEN. RPE-specific deletion of the mouse pten gene results in RPE cells that fail to maintain basolateral adhesions, undergo an epithelial-to-mesenchymal transi...

  2. Retinal structure and function preservation by polysaccharides of wolfberry in a mouse model of retinal degeneration

    OpenAIRE

    Wang, Ke; Xiao, Jia; Peng, Bo; Xing, Feiyue; So, Kwok-fai; Tipoe, George L.; Lin, Bin

    2014-01-01

    Retinitis pigmentosa (RP) is a heterogeneous group of inherited disorders caused by mutations in a variety of genes that are mostly expressed by rod cells, which results in initial death of rod photoreceptors followed by gradual death of cone photoreceptors. RP is currently untreatable and usually leads to partial or complete blindness. Here, we explored the potential neuroprotective effects of polysaccharides of wolfberry, which are long known to possess primary beneficial properties in the ...

  3. Living with Carotid Artery Disease

    Science.gov (United States)

    ... Living With Clinical Trials Links Related Topics Atherosclerosis Carotid Endarterectomy Carotid Ultrasound Stents Stroke Send a link to ... page from the NHLBI on Twitter. Living With Carotid Artery Disease If you have carotid artery disease, you can ...

  4. Peripheral Artery Disease and Diabetes

    Science.gov (United States)

    ... High Blood Pressure Tools & Resources Stroke More Peripheral Artery Disease & Diabetes Updated:Oct 7,2014 People with diabetes are at higher risk of developing peripheral artery disease (PAD) . And individuals with PAD are four ...

  5. All about Peripheral Arterial Disease

    Science.gov (United States)

    All About Peripheral Arterial Disease American Diabetes Association? ? 1–800–DIABETES (342–2383)? ? www.diabetes.org ©2009 ... Diabetes Association, Inc. 2/14 Toolkit No. 25: All About Peripheral Arterial Disease continued have PAD. The ...

  6. Pharmacological modulation of arterial stiffness.

    LENUS (Irish Health Repository)

    Boutouyrie, Pierre

    2011-09-10

    Arterial stiffness has emerged as an important marker of cardiovascular risk in various populations and reflects the cumulative effect of cardiovascular risk factors on large arteries, which in turn is modulated by genetic background. Arterial stiffness is determined by the composition of the arterial wall and the arrangement of these components, and can be studied in humans non-invasively. Age and distending pressure are two major factors influencing large artery stiffness. Change in arterial stiffness with drugs is an important endpoint in clinical trials, although evidence for arterial stiffness as a therapeutic target still needs to be confirmed. Drugs that independently affect arterial stiffness include antihypertensive drugs, mostly blockers of the renin-angiotensin-aldosterone system, hormone replacement therapy and some antidiabetic drugs such as glitazones. While the quest continues for \\'de-stiffening drugs\\

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

    Directory of Open Access Journals (Sweden)

    Kita M

    2013-03-01

    Full Text Available 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

  8. Evaluation of ultraviolet light toxicity on cultured retinal pigment epithelial and retinal ganglion cells

    Directory of Open Access Journals (Sweden)

    Sankarathi Balaiya

    2010-01-01

    Full Text Available Sankarathi Balaiya, Ravi K Murthy, Vikram S Brar, Kakarla V ChalamDepartment of Ophthalmology, University of Florida College of Medicine, Jacksonville, FL, USAPurpose: Our study is aimed at evaluating the role of UVB light in inducing cytotoxicity in an in vitro model.Methods: RGC-5 and ARPE-19 cells were exposed to different time periods of UVB light: 0, 15, 30, and 45 min. They were subsequently examined for changes in cell morphology, cell viability (neutral red uptake assay, generation of reactive oxygen species (ROS, expression of bax, bcl-2 and cytochome C by reverse transcriptase polymerase chain reaction and western blot, respectively.Results: Dose-dependent reduction in cell viability to UVB light was demonstrated with parallel increase in ROS. Increased duration of exposure (>15 minutes, was associated with increased expression of bax and cytochrome C, and absence of bcl-2 expression.Conclusion: UVB light exposure results in cell cytotoxicity. The concomitant generation of ROS and expression of apoptotic markers suggests the role of oxidative stress in UVB-mediated apoptosis in an in vitro model of retinal ganglion and pigment epithelial cells.Keywords: ultraviolet light, retinal pigment epithelium, retinal ganglion cell, reactive oxygen species, cytochrome C

  9. Baseline predictors of visual acuity and retinal thickness in patients with retinal vein occlusion.

    Science.gov (United States)

    Kim, Sang Jin; Yoon, Young Hee; Kim, Ha Kyoung; Yoon, Hee Seong; Kang, Se Woong; Kim, June-Gone; Park, Kyu Hyung; Jo, Young Joon; Lee, Dong-Hoon

    2015-04-01

    This study investigated the baseline predictors of best corrected visual acuity (BCVA) and central retinal thickness (CRT) at 6 months in patients with treatment-naïve branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO). This multicenter, interventional case series included 208 BRVO and 123 CRVO patients with follow-up period of 6 months or more. Outcome measures of BCVA (logMAR) included absolute change from baseline and a gain or loss of ? 0.3 from baseline. Outcome measures of CRT included absolute change from baseline and a measurement of ? 250 µm or ? 400 µm at 6 months. Univariate and multiple regression analyses were done to find baseline predictors. For BRVO, younger age, worse baseline BCVA, and shorter duration of symptom were associated with more gain in BCVA. For CRVO, worse baseline BCVA was associated with more gain in BCVA. For CRT outcomes, higher baseline CRT predicted greater decrease at 6 months in both BRVO and CRVO. Younger age and better baseline BCVA were associated with an increased likelihood of measurement of a ? 250 µm outcome for BRVO and CRVO, respectively. For CRVO, smoking was associated with greater decrease from baseline and decreased likelihood of measurement of a CRT ? 400 µm at 6 months. In conclusion, several baseline factors including age, symptom duration, and baseline BCVA and CRT are associated with BCVA and CRT outcomes at 6 months, which may help to predict disease course for RVO patients. PMID:25829817

  10. CAROTID ARTERY DISEASE

    Directory of Open Access Journals (Sweden)

    H. Van Damme

    2009-05-01

    Full Text Available Carotid artery disease (CAD become a commonly seen disease in general medical practice, due to the general population aging. Stroke, one of the most frequent complications of CAD and represents the third cause of death in Western countries. The leading cause of stroke in CAD is atheroembolism rather than flow-reduction. This paper reviewed imaging techniques, medical treatment and esepecially carotid endarterectomy (from point of view of indications, surgical technique and results and carotid artery stenting for the correct management of CAD.

  11. Arterial disease after radiotherapy

    International Nuclear Information System (INIS)

    Disease of the large arterial vessels is a relatively unknown complication of radiotherapy. However, it should be considered in the same manner as the other complications of irradiation when a tumour recurrence is suspected. The experimental studies of Kirkpatrick and Konings, demonstrating the synergy between irradiation and hypercholesterolemia in the precocity and gravity of vascular complications are recalled. The different localisations reported in the litterature are discussed: coronary, pulmonary, thoracic aorta, supra aortic, renal, digestive and ilio-femoral arteries. Finally, the difficulty of diagnosis of post-radiotherapy without clinical, radiological or anatomopathological confirmation, is underlined

  12. Radiative transport in large arteries

    OpenAIRE

    Ruh, Dominic; Subramanian, Sivaraman; Theodor, Michael; Zappe, Hans; Seifert, Andreas

    2013-01-01

    A refined model for the photon energy distribution in a living artery is established by solving the radiative transfer equation in a cylindrical geometry, using the Monte Carlo method. Combining this model with the most recent experimental values for the optical properties of flowing blood and the biomechanics of a blood-filled artery subject to a pulsatile pressure, we find that the optical intensity transmitted through large arteries decreases linearly with increasing arterial distension. T...

  13. Hipertensión arterial: aspectos genéticos / Arterial hypertension: genetics

    Scientific Electronic Library Online (English)

    María Isabel, Quiroga de Michelena.

    2010-12-01

    Full Text Available La regulación de la presión arterial (PA) es un proceso complejo, con intervención de múltiples variantes genéticas y epigenéticas que son objeto de la presente revisión. La disrupción del equilibrio entre los factores mencionados y su interacción con el ambiente lleva a la hipertensión arterial (HT [...] A), que en la gran mayoría de las veces es primaria o esencial. Se revisa los genes involucrados, los raros cuadros de HTA de origen monogénico, y las perspectivas en farmacogenómica, así como las tendencias hacia la medicina personalizada y con mayor participación activa del paciente en el cuidado de su propia salud. Abstract in english Regulation of blood pressure depends on complex mechanisms that include multiple genetic and epigenetic variations. There is a delicate balance between genetic, epigenetic and environmental factors that, when disrupted, lead to hypertension. In most cases blood hypertension is primary or essential, [...] and rarely is inherited through mutation of a single gene. This review will focus on genes involved in multifactorial blood hypertension and in the rare cases of monogenic hypertension. The pharmacogenomic advances and perspectives in the era of genomic medicine will also be reviewed.

  14. Regeneration of the retina: toward stem cell therapy for degenerative retinal diseases

    Science.gov (United States)

    Jeon, Sohee; Oh, Il-Hoan

    2015-01-01

    Degenerative retinal diseases affect millions of people worldwide, which can lead to the loss of vision. However, therapeutic approaches that can reverse this process are limited. Recent efforts have allowed the possibility of the stem cell-based regeneration of retinal cells and repair of injured retinal tissues. Although the direct differentiation of pluripotent stem cells into terminally differentiated photoreceptor cells comprises one approach, a series of studies revealed the intrinsic regenerative potential of the retina using endogenous retinal stem cells. Muller glial cells, ciliary pigment epithelial cells, and retinal pigment epithelial cells are candidates for such retinal stem cells that can differentiate into multiple types of retinal cells and be integrated into injured or developing retina. In this review, we explore our current understanding of the cellular identity of these candidate retinal stem cells and their therapeutic potential for cell therapy against degenerative retinal diseases. [BMB Reports 2015; 48(4): 193-199] PMID:25560700

  15. Changes in the retinal veins in acute optic neuritis.

    DEFF Research Database (Denmark)

    Engell, T; Sellebjerg, F

    1999-01-01

    OBJECTIVE: To investigate patients with acute optic neuritis (ON) for changes of the retinal veins. MATERIAL AND METHODS: Seventy-six patients with acute ON were extensively neuro-ophthalmologically examined. RESULTS: Multiple sclerosis (MS) was found in 41 patients of whom 1 had periphlebitis retinae (PR) and 2 had venous sheathing (VS). Probable MS was found in 15 patients without prior symptoms of MS. One had PR and VS, and 2 had VS. Twenty patients had mono-symptomatic ON, none had retinal changes. CONCLUSION: Changes of the retinal veins should alert the clinician to a probable diagnosis of MS. ON appears frequently as the initial symptom of MS. Our observation of VS in these patients suggest that clinically silent retinal disease activity had occurred prior to the ON

  16. Chlorogenic acid and coffee prevent hypoxia-induced retinal degeneration.

    Science.gov (United States)

    Jang, Holim; Ahn, Hong Ryul; Jo, Hyoung; Kim, Kyung-A; Lee, Eun Ha; Lee, Ki Won; Jung, Sang Hoon; Lee, Chang Y

    2014-01-01

    This study explored whether chlorogenic acid (CGA) and coffee have protective effects against retinal degeneration. Under hypoxic conditions, the viability of transformed retinal ganglion (RGC-5) cells was significantly reduced by treatment with the nitric oxide (NO) donor S-nitroso-N-acetylpenicillamine (SNAP). However, pretreatment with CGA attenuated cell death in a concentration-dependent manner. In addition, CGA prevented the up-regulation of apoptotic proteins such as Bad and cleaved caspase-3. Similar beneficial effects of both CGA and coffee extracts were observed in mice that had undergone an optic nerve crush (ONC) procedure. CGA and coffee extract reduced cell death by preventing the down-regulation of Thy-1. Our in vitro and in vivo studies demonstrated that coffee and its major component, CGA, significantly reduce apoptosis of retinal cells induced by hypoxia and NO, and that coffee consumption may help in preventing retinal degeneration. PMID:24295042

  17. CMV retinitis in China and SE Asia: the way forward

    Directory of Open Access Journals (Sweden)

    Heiden David

    2011-11-01

    Full Text Available Abstract AIDS-related CMV retinitis is a common clinical problem in patients with advanced HIV/AIDS in China and Southeast Asia. The disease is causing blindness, and current clinical management, commonly characterized by delayed diagnosis and inadequate treatment, results in poor clinical outcomes: 21% - 36% of eyes with CMV retinitis are already blind at the time the diagnosis is first established by an ophthalmologist. CMV retinitis also identifies a group of patients at extraordinary risk of mortality, and the direct or indirect contribution of extra-ocular CMV disease to AIDS-related morbidity and mortality is currently unmeasured and clinically often overlooked. The obvious way to improve clinical management of CMV retinitis is to screen all patients with CD4 counts

  18. A genetic analysis of retinitis pigmentosa

    Directory of Open Access Journals (Sweden)

    Shanker Jayashree

    1993-01-01

    Full Text Available The data consists of sixty probands affected with Retinitis pigmentosa. Syndromic cases were found in five percent of the RP probands. Segregation analysis was carried out on proband sibship data. The ascertainment probability was estimated at 0.5517. Analysis of the data by parental mating types of proband sibships indicated the presence of dominant forms of RP (2.05%. Analysis of proband sibships indicated the presence of low risk families in the Normal x Normal matings (45% and in the consanguineous matings (40%. The hypothesis of recessive inheritance could be confirmed only in multiplex sibships (p = 0.383 +/- 0.0793. Data on proband matings though incomplete conformed in general to autosomal recessive gene hypothesis.

  19. Multifractal Analysis of Human Retinal Vessels

    CERN Document Server

    Stosic, T

    2004-01-01

    In this work it is shown that vascular structures of the human retina represent geometrical multifractals, characterized by a hierarchy of exponents rather then a single fractal dimension. A number of retinal images from the STARE database (www.parl.clemson.edu/stare) are analyzed, corresponding to both normal and pathological states of the retina. In all studied cases a clearly multifractal behavior is observed, where capacity dimension is always found to be smaller then the information dimension, which is in turn always smaller then the correlation dimension, all the three being significantly lower then the DLA (Diffusion Limited Aggregation) fractal dimension. We also observe a tendency of images corresponding to the normal state of the retina to have higher generalized dimensions and a wider spectrum range, in comparison with the pathological cases.

  20. Bilateral retinitis following Chikun- gunya fever

    Directory of Open Access Journals (Sweden)

    Murthy Krishna

    2008-01-01

    Full Text Available A 35-year-old male with a history of chikungunya fever, presented with diminution of vision in the right eye of one-week duration. His best corrected visual acuity (BCVA was counting fingers 2 meters and 20/20 (Snellens in the right and left eyes respectively. A diagnosis of neuroretinitis was made in the right eye while left eye showed features of retinitis. ELISA (serum and polymerase chain reaction (aqueous were positive for herpes simplex virus. The lesions did not show any response to antiviral or steroid treatment and appeared to be self-limiting. At five months follow-up, lesions had resolved well with BCVA of 20/120 and 20/20 in the right and left eyes respectively.

  1. Intraretinal proliferation induced by retinal detachment

    International Nuclear Information System (INIS)

    Cellular proliferation after retinal detachment was studied by 3H-thymidine light microscopic autoradiography in cats that had experimental detachments of 0.5-180 days duration. The animals underwent labeling 2 hr before death with an intraocular injection of 200 microCi of 3H-thymidine. The number of labeled nuclei were counted in 1-micron thick tissue sections in regions of detachment, in regions of the experimental eyes that remained attached, and in control eyes that had no detachments. In the normal eye, in one that had only the lens and vitreous removed, and in the eyes with 0.5- and 1-day detachments, the number of labeled nuclei ranged from 0/mm (0.5-day detachment) to 0.38/mm (lens and vitreous removed only). By 2 days postdetachment, the number of labeled nuclei increased to 2.09/mm. The highest levels of labeling occurred in two animals with detachments of 3 (7.86/mm) and 4 (7.09/mm) days. Thereafter, the numbers declined steadily until near-baseline counts were obtained at 14 days. The number of labeled nuclei was slightly elevated in the attached regions of two animals with 3-day detachments. Labeled cell types included: Mueller cells, astrocytes, pericytes, and endothelial cells of the retinal vasculature, and both resident (microglial cells) and invading macrophages. In an earlier study RPE cells were also shown to proliferate in response to detachment. Thus, these data show that proliferation is a rapid response to detachment, reaion is a rapid response to detachment, reaching a maximum within 4 days, and that virtually every nonneuronal cell type in the retina can participate in this response. The data suggest that events leading to such clinical manifestations as proliferative vitreoretinopathy and subretinal fibrosis may have their beginnings in this very early proliferative response

  2. Intraretinal proliferation induced by retinal detachment

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, S.K.; Erickson, P.A.; Lewis, G.P.; Anderson, D.H. (Univ. of California, Santa Barbara (USA))

    1991-05-01

    Cellular proliferation after retinal detachment was studied by {sup 3}H-thymidine light microscopic autoradiography in cats that had experimental detachments of 0.5-180 days duration. The animals underwent labeling 2 hr before death with an intraocular injection of 200 microCi of {sup 3}H-thymidine. The number of labeled nuclei were counted in 1-micron thick tissue sections in regions of detachment, in regions of the experimental eyes that remained attached, and in control eyes that had no detachments. In the normal eye, in one that had only the lens and vitreous removed, and in the eyes with 0.5- and 1-day detachments, the number of labeled nuclei ranged from 0/mm (0.5-day detachment) to 0.38/mm (lens and vitreous removed only). By 2 days postdetachment, the number of labeled nuclei increased to 2.09/mm. The highest levels of labeling occurred in two animals with detachments of 3 (7.86/mm) and 4 (7.09/mm) days. Thereafter, the numbers declined steadily until near-baseline counts were obtained at 14 days. The number of labeled nuclei was slightly elevated in the attached regions of two animals with 3-day detachments. Labeled cell types included: Mueller cells, astrocytes, pericytes, and endothelial cells of the retinal vasculature, and both resident (microglial cells) and invading macrophages. In an earlier study RPE cells were also shown to proliferate in response to detachment. Thus, these data show that proliferation is a rapid response to detachment, reaching a maximum within 4 days, and that virtually every nonneuronal cell type in the retina can participate in this response. The data suggest that events leading to such clinical manifestations as proliferative vitreoretinopathy and subretinal fibrosis may have their beginnings in this very early proliferative response.

  3. Retinal nerve fibre layer polarimetry: histological and clinical comparison

    OpenAIRE

    Morgan, JE; Waldock, A.; Jeffery, G; COWEY, A

    1998-01-01

    AIMS—To compare histological thickness of the retinal nerve fibre layer in the primate with retardation measurements obtained in vivo using the Mark II Nerve Fiber Analyzer (NFA, Laser Diagnostic Technologies, San Diego, USA).?METHODS—Scanning laser polarimetry was performed on both eyes of a healthy anaesthetised adult primate (Macaca mulatta). The retinal nerve fibre layer thickness was measured in the eye with the best polarimetry image. A nerve fibre layer thickness map was scaled a...

  4. Evaluation of patients with pseudoexfoliation syndrome with heidelberg retinal tomography

    OpenAIRE

    Mehmet Ozbas; Suleyman Kugu; Ihsan Yilmaz; Gurkan Erdogan; M. Kazim Erol; Baran Kandemir

    2013-01-01

    Objective: To evaluate the optic disk and retinal nerve fiber layer (RNFL) in patients with Pseudoexfoliation Syndrome (PES) with Heidelberg Retinal Tomography (HRT) and its comparison with normal control group. Materials and Methods: 40 patients were included in this retrospective study. Group 1 was formed by 20 patients who had pseudoexfoliation in their anterior chamber but no other eye disease and Group 2 was formed by 20 persons who had not any eye disease. Mean age was 66.5±9.20 (52...

  5. Primary rhegmatogenous retinal detachment: clinical epidemiology and genetic aetiology

    OpenAIRE

    Mitry, Danny

    2013-01-01

    Primary rhegmatogenous retinal detachment (RRD) is one of the most common ophthalmic emergencies. RRD is caused by a full thickness break in the retina which initiates separation of the neurosensory retina from the underlying retinal pigment epithelium. The subsequent accumulation of fluid within this potential space extends the area of detachment and causes visual loss. Previous assessments of RRD incidence have demonstrated large differences in case definition and metho...

  6. Diffuse retinal injury from a non-penetrating TASER dart

    OpenAIRE

    Sayegh, Rony R.; Madsen, Kimberly A.; Adler, Jason D.; Johnson, Mary A.; Mathews, Michaela K.

    2011-01-01

    To describe a non-penetrating TASER gun injury resulting in a small exudative retinal detachment but significant visual acuity and retinal function loss as demonstrated by electroretinography (ERG). A 39-year-old man presented to the emergency department with a TASER barb embedded in his right lower lid. A complete clinical ophthalmologic examination and surgical extrication were performed, as well as radiologic imaging and Ganzfeld electroretinography. No scleral penetration was observed on ...

  7. A HYBRID RETINAL IMAGE REGISTRATION USING MUTUAL INFORMATION

    OpenAIRE

    Pradeepa Palraj; Ila.Vennila

    2013-01-01

    Image registration has tremendous applications in medical industry both in diagnosis and therapy. But registering the retinal images is very difficult task because of the structural and illumination criteria. Normal registration algorithms are proved to be less effective and more complicated for such applications. This study aims at combining two methods of retinal image registration: Vessel based and non-vessel based registration to overcome the drawbacks of the existing algorithms. This com...

  8. Branch retinal vein occlusion associated with quetiapine fumarate

    Directory of Open Access Journals (Sweden)

    Siang Lim

    2011-08-01

    Full Text Available Abstract Background To report a case of branch retinal vein occlusion in a young adult with bipolar mood disorder treated with quetiapine fumarate. Case Presentation A 29 years old gentleman who was taking quetiapine fumarate for 3 years for bipolar mood disorder, presented with sudden vision loss. He was found to have a superior temporal branch retinal vein occlusion associated with hypercholesterolemia. Conclusion Atypical antipsychotic drugs have metabolic side effects which require regular monitoring and prompt treatment.

  9. Phospholipid domains in bovine retinal rod outer segment disk membranes.

    OpenAIRE

    Albert, A. D.; Yeagle, P. L.

    1983-01-01

    Phospholipid behavior in bovine retinal rod outer segment disk membranes and in phosphatidylcholine membranes containing the photopigment rhodopsin is explored. 31P NMR spectra of these systems show two distinguishable resonances. One resembles closely the 31P NMR resonance normally obtained from phospholipid bilayers. The other resonance is much broader. Thus, there appear to be two phospholipid head-group domains in this retinal membrane. Each environment confers different properties on the...

  10. Retinal prosthetic strategy with the capacity to restore normal vision

    OpenAIRE

    Nirenberg, Sheila; Pandarinath, Chethan

    2012-01-01

    Retinal prosthetics offer hope for patients with retinal degenerative diseases. There are 20–25 million people worldwide who are blind or facing blindness due to these diseases, and they have few treatment options. Drug therapies are able to help a small fraction of the population, but for the vast majority, their best hope is through prosthetic devices [reviewed in Chader et al. (2009) Prog Brain Res 175:317–332]. Current prosthetics, however, are still very limited in the vision that th...

  11. Retinal photoreceptor fine structure in the mallard duck (Anas platyrhinchos)

    OpenAIRE

    Braekevelt, Charlie R.

    1990-01-01

    The retinal photoreceptors of the mallard duck (Anas platyrhynchos) consist of rods, single cones and double (unequal) cones present in a ratio of about 1:2:1. The rods have relatively large cylindrical outer segments which in the light-adapted state reach to the retinal epithelial (RPE) cell bodies and are surrounded by the pigment-laden apical processes of these RPE cells. The inner segment displays an apically located ellipsoid of mitochondria and plentiful ...

  12. TRAIL-Deficient Mice Exhibit Delayed Regression of Retinal Neovascularization

    OpenAIRE

    Hubert, Kristin E.; Davies, Michael H.; Stempel, Andrew J.; Griffith, Thomas S.; Powers, Michael R.

    2009-01-01

    While it is well established that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in various cell types, the role of TRAIL in regulation of retinal neovascularization (NV) has not been described. Here we determined the role of TRAIL in retinal NV during oxygen-induced retinopathy using TRAIL deficient (?/?) mice. TRAIL and its receptor, DR5, were expressed in wild-type retinas at all time points evaluated (postnatal days 12, 17, 21, 24) during oxygen-indu...

  13. Cytomegalovirus Retinitis after Intravitreal Bevacizumab Injection in an Immunocompetent Patient

    OpenAIRE

    Bae, So Hyun; Kim, Tae Wan; Chung, Hum; Heo, Jang Won

    2013-01-01

    We report a case of cytomegalovirus (CMV) retinitis after intravitreal bevacizumab injection. A 61-year-old woman with diabetic macular edema developed dense vitritis and necrotizing retinitis 3 weeks after intravitreal bevacizumab injection. A diagnostic vitrectomy was performed. The undiluted vitreous sample acquired by vitrectomy was analyzed by polymerase chain reaction and culture. Polymerase chain reaction of the vitreous was positive for CMV DNA. Other laboratory results did not show e...

  14. Unilateral retinitis pigmentosa and cone-rod dystrophy

    OpenAIRE

    Farrell, Donald F.

    2009-01-01

    Donald F FarrellEEG and Clinical Neurophysiology Laboratory, University of Washington Medical Center, Seattle, WA, USAPurpose: The purpose of this paper is to report 14 new cases of unilateral retinitis pigmentosa and three new cases of cone-rod dystrophy and to compare the similarities and dissimilarities to those found in the bilateral forms of these disorders.Methods: A total of 272 cases of retinitis pigmentosa and 167 cases of cone-rod dystrophy were studied by corneal full field electro...

  15. Large capillary aneurysms secondary to retinal venous obstruction.

    OpenAIRE

    Schulman, J.; Jampol, L. M.; Goldberg, M. F.

    1981-01-01

    Three patients had unusually large capillary aneurysms. Two of the patients had had previous branch vein occlusions, while a third had had a central retinal vein occlusion. The large capillary aneurysms were located in areas of ischaemic retina that were drained by the previously obstructed veins. Retinal ischaemia and, possibly, increased hydrostatic pressure following vein occlusion were postulated to result in the development of these atypical capillary aneurysms. They are similar in size ...

  16. Active Guidance for Laser Retinal Surgery with a Handheld Instrument

    OpenAIRE

    Becker, Brian C.; Valdivieso, Cristina Robles; Biswas, Joydeep; Lobes, Louis A.; Riviere, Cameron N.

    2009-01-01

    Laser photocoagulation is a standard interventional tool in vitreoretinal surgery. Commonly applied treatments such as grid photocoagulation and panretinal photocoagulation involve the application of hundreds of dot-like laser burns to the retina. In order to enhance the accuracy and reduce the tedium of this procedure, we are developing a robot-assisted technique for retinal laser photocoagulation that includes software for planning patterns of laser burns on a retinal image and uses an acti...

  17. Emotional state of family members of adults with retinal degeneration

    OpenAIRE

    Chacón-López, Helena; López-Justicia, María Dolors; Fernández-Jiménez, Carolina; Chacón-Medina, Antonio; Polo-Sánchez, María T.

    2013-01-01

    Various studies have documented the emotional changes that accompany the loss of vision in people with retinal degeneration (such as Retinitis Pigmentosa), but the emotional state of family members who live with them has not been extensively studied. However it is known that chronic diseases have repercussions not only on the well-being and quality of life of those affected, but also on their families, possibly making them more susceptible to depression and/or anxiety. Results from 37 family ...

  18. Segmentation of retinal OCT images using a random forest classifier

    OpenAIRE

    Lang, Andrew; Carass, Aaron; Sotirchos, Elias; Calabresi, Peter; Prince, Jerry L

    2013-01-01

    Optical coherence tomography (OCT) has become one of the most common tools for diagnosis of retinal abnormalities. Both retinal morphology and layer thickness can provide important information to aid in the differential diagnosis of these abnormalities. Automatic segmentation methods are essential to providing these thickness measurements since the manual delineation of each layer is cumbersome given the sheer amount of data within each OCT scan. In this work, we propose a new method for reti...

  19. Evidence-based medicine regarding the prevention of retinal detachment.

    OpenAIRE

    Wilkinson, C. P.

    1999-01-01

    PURPOSE: To assess the quality of information in the literature regarding the prevention of retinal detachment in an effort to establish appropriate practice guidelines. METHODS: A panel of vitreoretinal experts performed a literature review of all publications in the English language for articles about prevention of retinal detachment. These article were then used to prepare recommendations for patient care in an American Academy of Ophthalmology "Preferred Practice Pattern" (PPP). Each reco...

  20. Enhanced differentiation of retinal progenitor cells using microfabricated topographical cues

    OpenAIRE

    Steedman, Mark R.; Sarah L. Tao; Klassen, Henry; Desai, Tejal A

    2010-01-01

    Due to the retina’s inability to replace photoreceptors lost during retinal degeneration, significant interest has been placed in methods to implant replacement cells. Polymer scaffolds are increasingly being studied as vehicles for cellular delivery to degenerated retinas. Previously, we fabricated poly(methyl methacrylate) thin film scaffolds that increased survival and integration of implanted retinal progenitor cells (RPCs). Additionally, these scaffolds minimized the trauma and cellular ...