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Sample records for retinal hemorrhage

  1. Retinal hemorrhages in newborn.

    PubMed

    Govind, A; Kumari, S; Lath, N K

    1989-02-01

    Two hundred and fifty eight newborn babies were studied for the presence of retinal hemorrhages between 1-3 days of birth. The overall incidence of retinal hemorrhages was found to be 18.9%. It was observed that the incidence of retinal hemorrhages was higher in unassisted vaginal deliveries than in assisted births. Also, a two fold higher incidence was noted in term infants as compared to preterm babies. No association was seen with birth asphyxia.

  2. [Unusual retinal abnormality: retinal hemorrhages related to scurvy].

    PubMed

    Errera, M-H; Dupas, B; Man, H; Gualino, V; Gaudric, A; Massin, P

    2011-03-01

    A diet restricted to rice and boiled fruit and vegetables leads to vitamin C deficiency. We describe the third case, to our knowledge, of retinal hemorrhages related to scurvy. Reduced bilateral visual acuity in a 50-year-old patient was associated with macrocytic anemia, denutrition, and cutaneous ecchymoses. Oral vitamin C treatment provided subjective clinical improvement and regression of the retinal hemorrhages on fundus examination, with no side effects. Vitamin C plays an important role in collagen stability in vascular and bone walls. PMID:21392843

  3. [Unusual retinal abnormality: retinal hemorrhages related to scurvy].

    PubMed

    Errera, M-H; Dupas, B; Man, H; Gualino, V; Gaudric, A; Massin, P

    2011-03-01

    A diet restricted to rice and boiled fruit and vegetables leads to vitamin C deficiency. We describe the third case, to our knowledge, of retinal hemorrhages related to scurvy. Reduced bilateral visual acuity in a 50-year-old patient was associated with macrocytic anemia, denutrition, and cutaneous ecchymoses. Oral vitamin C treatment provided subjective clinical improvement and regression of the retinal hemorrhages on fundus examination, with no side effects. Vitamin C plays an important role in collagen stability in vascular and bone walls.

  4. Retinal hemorrhage after cardiopulmonary resuscitation with chest compressions.

    PubMed

    Pham, Hang; Enzenauer, Robert W; Elder, James E; Levin, Alex V

    2013-06-01

    Retinal hemorrhages in children in the absence of risk factors are regarded to be pathognomonic of shaken baby syndrome or other nonaccidental injuries. The physician must decide whether the retinal hemorrhages in children without risk factors are due to abuse or cardiopulmonary resuscitation with chest compression (CPR-CC). The objective of this study was to determine if CPR-CC can lead to retinal hemorrhages in children. Twenty-two patients who received in-hospital CPR-CC between February 15, 1990, and June 15, 1990, were enrolled. Pediatric ophthalmology fellows carried a code beeper and responded to calls for cardiopulmonary arrest situations. At the scene of CPR-CC, an indirect funduscopic examination was conducted for presence of retinal hemorrhages in the posterior pole. Follow-up examinations were performed at 24 and 72 hours. Of the 22 patients, 6 (27%) had retinal hemorrhages at the time of CPR-CC. Of these 6 patients, 5 had risk factors for retinal hemorrhages. The sixth patient had no risk factors and may have represented the only true case of retinal hemorrhages due to CPR-CC. Retinal hemorrhages are uncommon findings after CPR-CC. Retinal hemorrhages that are found after CPR-CC usually occur in the presence of other risk factors for hemorrhage with a mild hemorrhagic retinopathy in the posterior pole.

  5. Retinal hemorrhagic lesions from femtosecond visible laser pulses

    NASA Astrophysics Data System (ADS)

    Stein, Cindy D.; Toth, Cynthia A.; Cain, Clarence P.; Noojin, Gary D.; Stolarski, David J.; Rockwell, Benjamin A.; Roach, William P.

    1994-08-01

    We present our clinical evaluation of hemorrhagic and non-hemorrhagic 90 fs single pulses in rabbits and primates. The rabbit and primate eye present unique in vivo models for evaluation of retinal and choroidal laser induced hemorrhages with distinct differences in their retinal anatomy. We found two different hemorrhagic events to occur in the posterior pole with delivery of 90 fs pulses. First, in the Dutch Belted rabbit, we found large amounts of energy per pulse (from 20 to 60 times ED50) were required for formation of subretinal hemorrhages. Second, in the Rhesus monkey, we found significant numbers of small intraretinal hemorrhages from relatively low energy 90 fs pulses. Both the Dutch Belted rabbit and the Rhesus monkey failed to consistently show subretinal hemorrhagic lesions form very high pulse energies. Our findings suggest more energy absorption at the level of the retinal circulation than the choroidal circulation with our pulse parameters. The effects of the laser on the retinal circulation may be due to the use of a wavelength of 580 nm. At this wavelength the oxyhemoglobin to melanin absorption ratio is nearly at its peak (approximately 0.40), perhaps allowing improved absorption in the retinal vasculature. One precaution with this finding, however, are the distinct differences between primate and non-primate ocular systems. Further studies are required to resolve the differences in damage at the level of the RPE and choroid between rabbits and primates.

  6. Evaluation of Temporal Association Between Vaccinations and Retinal Hemorrhage in Children

    PubMed Central

    Binenbaum, Gil; Christian, Cindy W.; Guttmann, Katy; Huang, Jiayan; Ying, Gui-shuang; Forbes, Brian J.

    2016-01-01

    Importance Vaccinations have been proposed as a cause of retinal hemorrhage in children, primarily as part of a defense strategy in high-stakes abusive head trauma cases. If vaccination injections cause retinal hemorrhage, this consideration would affect the evaluation of children for suspected child abuse. Objectives To describe the prevalence and causes of retinal hemorrhage among infants and young children in an outpatient ophthalmology clinic and to test the hypothesis that, if vaccination injections cause retinal hemorrhage, then retinal hemorrhage would be seen frequently and be temporally associated with immunization. Design, Setting, and Participants Retrospective cohort study between June 1, 2009, and August 30, 2012, at The Children's Hospital of Philadelphia pediatric ophthalmology clinics among 5177 children 1 to 23 months old undergoing a dilated fundus examination as an outpatient for any reason. Children with intraocular surgery or active retinal neovascularization were excluded from the study. Main outcomes and Measures The prevalence and causes of retinal hemorrhage, as well as the temporal association between vaccination injection within 7, 14, or 21 days preceding examination and retinal hemorrhage. Results Among 7675 outpatient fundus examinations, 9 of 5177 children had retinal hemorrhage for a prevalence of 0.17% (95% CI, 0.09%-0.33%). All 9 had abusive head trauma diagnosable with nonocular findings. Among a subset of 2210 children who had complete immunization records and underwent 3425 fundoscopic examinations, 163 children had an eye examination within 7 days of vaccination, 323 within 14 days, and 494 within 21 days. No children had retinal hemorrhage within 7 days of vaccination, 1 child had hemorrhage within 14 days, and no additional child had hemorrhage within 21 days. There was no temporal association between vaccination injection and retinal hemorrhage in the prior 7 days (P > .99), 14 days (P = .33), or 21 days (P = .46

  7. Association between retinal hemorrhagic pattern and macular perfusion status in eyes with acute branch retinal vein occlusion

    PubMed Central

    Muraoka, Yuki; Uji, Akihito; Tsujikawa, Akitaka; Murakami, Tomoaki; Ooto, Sotaro; Suzuma, Kiyoshi; Takahashi, Ayako; Iida, Yuto; Miwa, Yuko; Hata, Masayuki; Yoshimura, Nagahisa

    2016-01-01

    This prospective study included 63 eyes with acute branch retinal vein occlusion (BRVO) to evaluate the retinal hemorrhagic patterns at the posterior poles and explore their clinical relevance in macular perfusion differentiation. Retinal hemorrhagic patterns and macular perfusion status were evaluated via fundus photography and fluorescein angiography, respectively. Macular perfusion was judged as nonischemic in 30, ischemic in 28, and undeterminable in 5 among the 63 eyes. Predominant hemorrhagic patterns were flame-shaped in 39 (67.2%) and non-flame-shaped in 19 (32.8%) eyes. All 39 eyes with a flame-shaped hemorrhage showed a nonischemic macula. Of the 19 eyes classified as having a non-flame-shaped hemorrhage, 13 (68.4%) had an ischemic macula and 6 (31.6%) had a nonischemic macula (P < 0.001). Parallelism in eyes with a flame-shaped hemorrhage was higher than in those with a non-flame-shaped hemorrhage (P < 0.001), and in those with a nonischemic macula versus those with an ischemic macula (P < 0.001). The area under the curve for parallelism was 0.975 (P < 0.001), suggesting an accurate diagnostic parameter for macular perfusion differentiation. In conclusion, we objectively evaluated retinal hemorrhagic patterns at the posterior pole in BRVO using the parallelism method, which was useful in differentiating macular perfusion status. PMID:27334338

  8. The eye in child abuse: key points on retinal hemorrhages and abusive head trauma.

    PubMed

    Binenbaum, Gil; Forbes, Brian J

    2014-12-01

    This review presents an up-to-date overview of ocular injuries resulting from child abuse, with a spotlight on abusive head trauma. Retinal hemorrhage is a principle finding of inflicted head trauma. The specific pattern of hemorrhages holds valuable diagnostic information, which can help to guide multidisciplinary assessments of the likelihood of abuse. Indirect ophthalmoscopy through dilated pupils by an ophthalmologist is necessary for adequate examination and documentation of retinal findings. Initial pediatrician evaluation of the eye and indications for ophthalmological consultation are reviewed. Focus is then placed upon understanding retinal hemorrhage patterns, their diagnostic significance and likely pathophysiological mechanisms. The differential diagnosis of retinal hemorrhage in young children is discussed, highlighting key distinctions among retinal hemorrhage patterns, severity and frequencies, as well as other ocular findings. The most common cause of retinal hemorrhage in an infant is trauma, and most other causes can be identified by considering the hemorrhage pattern, ocular or systemic signs and the results of laboratory and imaging tests, when indicated. PMID:25501729

  9. Vitreous hemorrhage secondary to retinal vasculopathy in a patient with dyskeratosis congenita.

    PubMed

    Finzi, Alessandro; Morara, Mariachiara; Pichi, Francesco; Veronese, Chiara; Ciardella, Antonio P

    2014-08-01

    The aim of this study was to report a case of vitreous hemorrhage secondary to retinal vasculitis in a patient with dyskeratosis congenita. A 16-year-old white male was referred to the Ophthalmology Clinic due to deterioration of vision in his left eye. Medical history was significant for dyskeratosis congenita associated with thrombocytopenia. General physical examination revealed reticular pigmentation on the upper half of the chest, vertical ridges and splitting of finger nails, and oral mucosal leukoplakia. Ophthalmological examination of the anterior segment was unremarkable. Retinal examination revealed vitreous hemorrhage in the left eye veiling the retinal details. A possible history of trauma was denied. Fundus examination of the right eye showed retinal vascular sheathing with a few dot and blot retinal hemorrhages. Fluorescein angiography revealed extensive areas of non-perfusion beyond the equator in the right eye, later treated with scatter laser photocoagulation. We performed a 23-gauge vitrectomy with endolaser treatment of the new vascularization areas in the left eye. After 6 months, best-corrected visual acuity in the right and left eye was 20/20 and 20/25, respectively. Rather than being confined to anterior segment abnormalities like conjunctivitis, blepharitis and nasolacrimal duct obstruction which are reported in the literature, dyskeratosis congenita can cause significant visual loss due to retinal vasculitis and vitreous hemorrhage. Therefore physicians and ophthalmologists should be aware of this possibility and prompt diagnosis and treatment could prevent further visual loss in such patients. PMID:24114504

  10. Significance of retinal laser lesion location and subretinal hemorrhage in bridging choroidal neovascular complexes

    NASA Astrophysics Data System (ADS)

    Schuschereba, Steven T.; Clarkson, Donna R.; Valo, Lynn M.; Brown, Jeremiah, Jr.; Stuck, Bruce E.

    2003-06-01

    Purpose: To determine funduscopic criteria that will help predict when bridging choroidal neovascular (CNV) complexes will develop after laser retinal trauma and to define early preventive treatment targets. Methods: Ten rhesus monkeys were used and retinal lesions were produced by Nd:YAG exposures (20ns, 1-2mJ, 1064nm, min. spot size) simulating human accidental laser trauma to the central fundus. Funduscopy and fluorescein/ICG angiography were conducted at day 1, 4, and 14, and at 2 and 4 months, and animals terminated for histologic evaluation. Predisposition for bridging fibrovascular complexes was evaluated for single lesions, two small lesions showing coalescing hemorrhages, and multiple lesions involved with large field subretinal and vitreous hemorrhages. Results: Elevated CNVs were present in all single lesions with confined subretinal hemorrhages. All lesion sets that showed initial and small coalescing subretinal hemorrhages formed bridging CNV scars. No bridging CNVs occurred in lesion sets involving a vitreous hemorrhage adjacent to a confined, but small subretinal hemorrhage. In large field subretinal hemorrhages involving multiple laser lesions, complex CNV formation occurred. Extensive secondary photoreceptor losses occurred in confined hemorrhage and CNV zones. Conclusion: Trauma presenting with evidence of coalescing and confined subretinal hemorrhages between two adjacent lesions has a high chance of forming choroidal neovascular bridge complexes between the involved lesions. CNV formation may be related to the long residence time, break down products, and clearance processes of extravasated blood. Removal of trapped blood and curtailing angiogenesis and cellular proliferation may be helpful treatment strategies.

  11. Hemorrhagic Occlusive Retinal Vasculitis After First Eye Cataract Surgery Without Subsequent Second Eye Involvement.

    PubMed

    Balducci, Nicole; Savini, Giacomo; Barboni, Piero; Ducoli, Pietro; Ciardella, Antonio

    2016-08-01

    A case of monocular postoperative hemorrhagic occlusive retinal vasculitis (HORV) after uncomplicated bilateral cataract surgery is described. HORV is a severe syndrome that leads to painless visual loss after uncomplicated cataract surgery. The same surgical procedure was adopted in both eyes except for the use of intracameral vancomycin, which was injected only in the eye that developed HORV. Diffuse retinal ischemia with vascular sheathing and intraretinal hemorrhages were detected during the fourth postoperative day. Despite treatment, the patient developed severe neovascular glaucoma. This case supports the causative role of vancomycin in the pathogenesis of HORV and suggests avoiding it for chemoprophylaxis. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:764-766.]. PMID:27548454

  12. Risk factors associated with retinal hemorrhage in suspected abusive head trauma

    PubMed Central

    Burkhart, Zachary N.; Thurber, Clinton J.; Chuang, Alice Z.; Kumar, Kartik S.; Davis, Garvin H.; Kellaway, Judianne

    2015-01-01

    Purpose To determine risk factors associated with retinal hemorrhage (RH) in pediatric abusive head trauma (AHT) suspects. Methods Records of children aged 0–3 years hospitalized for suspected AHT from January 2007 to November 2011 were retrospectively reviewed in this case–control study. Children were classified into case and control groups based on RH presence. Medical history, presenting symptoms, reasons, and characteristics of injury were recorded. Logistic regression analysis was performed to identify risk factors. Results A total of 168 children (104 males) were included. Of these, 103 were classified as cases and 65 as controls. The mean age (with standard deviation) was 9.3 ± 8.3 months (range, 1 day-36 months). Of the 103 cases, 22 (21%) had subretinal hemorrhage, 9 (9%) had retinoschisis, and 1 (1%) had vitreous hemorrhage. Children presenting with lethargy or altered mental status (P < 0.0001), subdural hemorrhage (P < 0.0001), and other radiologic findings (eg, cerebral ischemia, diffuse axonal injury, hydrocephalus, or solid organ injury; P = 0.01546) were likely to have RH. All 23 children with skull or nonskull fracture without intracranial hemorrhage did not have RH (P < 0.0001 both categories). Conclusions Retinal hemorrhages were almost never found in the absence of intracranial hemorrhage and not found in the setting of fracture without intracranial hemorrhage. PMID:25828822

  13. Progressive Outer Retinal Necrosis Combined with Vitreous Hemorrhage in a Patient with Acquired Immunodeficiency Syndrome

    PubMed Central

    You, Yong Sung; Lee, Sung Jin; Lee, Sung Ho; Park, Chang Hyun

    2007-01-01

    Purpose To describe an unusual case of rapidly progressive outer retinal necrosis (PORN) with vitreous hemorrhage in a 41-year-old woman with acquired immunodeficiency syndrome (AIDS), who had retinitis developed from what was probably varicellar-zoster virus combined with cytomegalovirus (CMV) and herpes simplex type 1,2, as proven by the polymerase chain reaction restriction fragment length polymorphism method (PCR-RFLP). Methods This study is a case report detailing clinical follow-up and an aqueous humor test by PCR-RFLP. Results The deep, white retinal lesions coalesced and progressively expanded in a circumferential manner, with sparing of the perivascular retina. However, retinal and vitreous hemorrhages, unusual findings for PORN, could be noted around the optic nerve. Varicellar-zoster virus (VZV), cytomegalovirus (CMV), and herpes simplex types 1,2 (HSV-1,2) were detected in the aqueous humor by PCR. Conclusions PORN has been described as a variant of necrotizing herpetic retinopathy, occurring particularly in patients with AIDS. Although the etiologic agent has been reported to be VZV, concurrent or combined etiologic agents can include HSV-1, HSV-2, and CMV in AIDS patients. Therefore, combined antiviral therapy with acyclovir and ganciclovir could be more reasonable as an initial therapy. PMID:17460434

  14. [Two children with cerebral and retinal hemorrhages: do not diagnose shaken baby syndrome too rapidly].

    PubMed

    Botte, A; Mars, A; Wibaut, B; De Foort-Dhellemmes, S; Vinchon, M; Leclerc, F

    2012-01-01

    We report on 2 cases associating retinal (RH) and cerebral hemorrhages (CH), which first suggested the diagnosis of shaken baby syndrome (SBS). After an etiologic search, the diagnosis was corrected: the first case was a late hemorrhagic disease of the newborn and the second case hemophilia A. RH is a major feature of SBS, although not pathognomonic. There is no specific RH of SBS but they usually affect the posterior retinal pole. Typically, RHs of SBS are present in both eyes, although unilateral RHs do not exclude the diagnosis of SBS. The relationship between RH and CH has been reported in SBS but also in other diseases. Thus, one must search for hemostasis abnormalities, even though the clinical presentation suggests SBS. Ignoring SBS as well as coming to the conclusion of SBS too quickly should be avoided. Diagnostic difficulties may be related to the number of physicians involved and their interpretation of the facts. These 2 cases underline the need for working as a team that includes hematologists able to interpret coagulation parameters.

  15. Retinal Vessel Analysis (RVA) in the Context of Subarachnoid Hemorrhage - A Proof of Concept Study

    PubMed Central

    Weiss, Miriam; Clusmann, Hans; Fuest, Matthias; Mueller, Marguerite; Brockmann, Marc Alexander; Vilser, Walthard; Schmidt-Trucksäss, Arno; Hoellig, Anke; Seiz, Marcel; Thomé, Claudius; Kotliar, Konstantin; Schubert, Gerrit Alexander

    2016-01-01

    Background Timely detection of impending delayed cerebral ischemia after subarachnoid hemorrhage (SAH) is essential to improve outcome, but poses a diagnostic challenge. Retinal vessels as an embryological part of the intracranial vasculature are easily accessible for analysis and may hold the key to a new and non-invasive monitoring technique. This investigation aims to determine the feasibility of standardized retinal vessel analysis (RVA) in the context of SAH. Methods In a prospective pilot study, we performed RVA in six patients awake and cooperative with SAH in the acute phase (day 2–14) and eight patients at the time of follow-up (mean 4.6±1.7months after SAH), and included 33 age-matched healthy controls. Data was acquired using a manoeuvrable Dynamic Vessel Analyzer (Imedos Systems UG, Jena) for examination of retinal vessel dimension and neurovascular coupling. Results Image quality was satisfactory in the majority of cases (93.3%). In the acute phase after SAH, retinal arteries were significantly dilated when compared to the control group (124.2±4.3MU vs 110.9±11.4MU, p<0.01), a difference that persisted to a lesser extent in the later stage of the disease (122.7±17.2MU, p<0.05). Testing for neurovascular coupling showed a trend towards impaired primary vasodilation and secondary vasoconstriction (p = 0.08, p = 0.09 resp.) initially and partial recovery at the time of follow-up, indicating a relative improvement in a time-dependent fashion. Conclusion RVA is technically feasible in patients with SAH and can detect fluctuations in vessel diameter and autoregulation even in less severely affected patients. Preliminary data suggests potential for RVA as a new and non-invasive tool for advanced SAH monitoring, but clinical relevance and prognostic value will have to be determined in a larger cohort. PMID:27388619

  16. Optical Coherence Tomography Follow-up of an Unusual Case of Old Rhegmatogenous Retinal Detachment With a Hemorrhagic Macrocyst at the Macula.

    PubMed

    Tripathy, Koushik; Bypareddy, Ravi; Chawla, Rohan; Kumawat, Babulal

    2015-01-01

    A 32-year-old female presented with visual acuity of hand movement close to face, an old inferior rhegmatogenous retinal detachment (RRD), and a large hemorrhagic macular macrocyst (HMM) in the right eye. After 2 weeks of successful vitreoretinal surgery, the HMM started decreasing in height and resolved by 3 months. On optical coherence tomography, a zone of hyperreflectivity in the outer retinal layers was evident on resolution of the cyst. At final follow-up, the visual acuity improved to 1/60 only. Though HMM resolved completely after retinal reattachment, alteration and thickening of microarchitecture of the outer retinal layers ensued. PMID:26599252

  17. A finite element analysis of the retinal hemorrhages accompanied by shaken baby syndrome/abusive head trauma.

    PubMed

    Yoshida, Makoto; Yamazaki, Junpei; Mizunuma, Hiroshi

    2014-11-01

    We aimed to elucidate the mechanism of the retinal hemorrhage (RH) accompanied by shaken baby syndrome or abusive head trauma (SBS/AHT) by analyses using a computational model. We focused on a hypothesis that the vitreoretinal traction due to acceleration and deceleration caused by abusive shaking leads to retinal hemorrhage. A finite element (FE) mechanical model with simple spherical geometry was constructed. When the FE mechanical model was virtually shaken, the intensity of the stress applied to the retinal plane agreed well with the results from an analysis using a physical model made of agar gel. Impacts due to falling events induced more intensive tensile stresses, but with shorter duration, than the shake did. By applying a mathematical theory on tackiness, we propose a hypothesis that the time integration of the stress, in the unit of Pa·s, would be a good predictor of the RH accompanied by SBS/AHT. A single cycle of abusive shake amounted to 101Pa·s of time integration of inflicted stress, while a single impact event amounted to 36Pa·s. This would explain the paradoxical observation that shaking induces RH while RH due to impact events is only seen in a major event such as a fatal motor vehicle accident. PMID:25282076

  18. A finite element analysis of the retinal hemorrhages accompanied by shaken baby syndrome/abusive head trauma.

    PubMed

    Yoshida, Makoto; Yamazaki, Junpei; Mizunuma, Hiroshi

    2014-11-01

    We aimed to elucidate the mechanism of the retinal hemorrhage (RH) accompanied by shaken baby syndrome or abusive head trauma (SBS/AHT) by analyses using a computational model. We focused on a hypothesis that the vitreoretinal traction due to acceleration and deceleration caused by abusive shaking leads to retinal hemorrhage. A finite element (FE) mechanical model with simple spherical geometry was constructed. When the FE mechanical model was virtually shaken, the intensity of the stress applied to the retinal plane agreed well with the results from an analysis using a physical model made of agar gel. Impacts due to falling events induced more intensive tensile stresses, but with shorter duration, than the shake did. By applying a mathematical theory on tackiness, we propose a hypothesis that the time integration of the stress, in the unit of Pa·s, would be a good predictor of the RH accompanied by SBS/AHT. A single cycle of abusive shake amounted to 101Pa·s of time integration of inflicted stress, while a single impact event amounted to 36Pa·s. This would explain the paradoxical observation that shaking induces RH while RH due to impact events is only seen in a major event such as a fatal motor vehicle accident.

  19. Genetic pediatric retinal diseases

    PubMed Central

    Say, Emil Anthony T.

    2014-01-01

    Hereditary pediatric retinal diseases are a diverse group of disorders with pathologies affecting different cellular structures or retinal development. Many can mimic typical pediatric retinal disease such as retinopathy of prematurity, vitreous hemorrhage, retinal detachment and cystoid macular edema. Multisystem involvement is frequently seen in hereditary pediatric retinal disease. A thorough history coupled with a good physical examination can oftentimes lead the ophthalmologist or pediatrician to the correct genetic test and correct diagnosis. In some instances, evaluation of parents or siblings may be required to determine familial involvement when the history is inconclusive or insufficient and clinical suspicion is high.

  20. Genetic pediatric retinal diseases.

    PubMed

    Say, Emil Anthony T

    2014-12-01

    Hereditary pediatric retinal diseases are a diverse group of disorders with pathologies affecting different cellular structures or retinal development. Many can mimic typical pediatric retinal disease such as retinopathy of prematurity, vitreous hemorrhage, retinal detachment and cystoid macular edema. Multisystem involvement is frequently seen in hereditary pediatric retinal disease. A thorough history coupled with a good physical examination can oftentimes lead the ophthalmologist or pediatrician to the correct genetic test and correct diagnosis. In some instances, evaluation of parents or siblings may be required to determine familial involvement when the history is inconclusive or insufficient and clinical suspicion is high. PMID:27625880

  1. Retinitis Pigmentosa

    MedlinePlus

    ... Action You are here Home › Retinal Diseases Listen Retinitis Pigmentosa What is retinitis pigmentosa? What are the symptoms? ... available? Are there any related diseases? What is retinitis pigmentosa? Retinitis pigmentosa (RP) refers to a group of ...

  2. [Non-traumatic vitreous hemorrhage].

    PubMed

    Conart, J-B; Berrod, J-P

    2016-02-01

    Spontaneous vitreous hemorrhage is a serious disease whose incidence is 7 per 100,000 people per year. Posterior vitreous detachment with or without retinal tear, diabetic retinopathy, vascular proliferation after retinal vein occlusion, age-related macular degeneration and Terson's syndrome are the most common causes. Repeated ultrasonography may ignore a retinal tear or detachment and delay vitrectomy that is the only treatment for serious forms. The occurrence of retinal tear or detachment is a surgical emergency as well as rubeosis or diabetic tractional retinal detachment involving the macula. Intravitreal injection of antiangiogenic agents are helpful in clearing the vitreous cavity, facilitating laser photocoagulation and reducing the risks of bleeding during preretinal neovascular membranes dissection. PMID:26826742

  3. Retinal lesions in septicemia.

    PubMed

    Neudorfer, M; Barnea, Y; Geyer, O; Siegman-Igra, Y

    1993-12-15

    We explored the association between septicemia and specific retinal lesions in a prospective controlled study. Hemorrhages, cotton-wool spots, or Roth's spots were found in 24 of 101 septicemic patients (24%), compared to four of 99 age- and gender-matched control patients (4%) (P = .0002). There was no significant association between types of organisms or focus of infection and the presence of specific lesions. Histologic examination of affected eyes disclosed cytoid bodies in the nerve fiber layer without inflammation. A definite association between septicemia and retinal lesions was found and indicates the need for routine ophthalmoscopy in septicemic patients. PMID:8250076

  4. Hemorrhagic Stroke

    MedlinePlus

    A stroke is a medical emergency. There are two types - ischemic and hemorrhagic. Hemorrhagic stroke is the less common type. It happens when ... an artery wall that breaks open. Symptoms of stroke are Sudden numbness or weakness of the face, ...

  5. [Subretinal hemorrhage. Natural course and staging].

    PubMed

    Bopp, S

    2012-07-01

    Subretinal hemorrhages are a complication of various diseases which arise from the choroidal or retinal circulation. Most commonly the underlying pathology is a choroidal neovascular membrane (CNV) especially in patients with age-related macular degeneration (AMD). Less common ocular diseases are those with non-AMD-related CNV and retinal arterial macroaneurysms (RAM). Case studies have demonstrated a poor prognosis, however, a significant portion have favorable outcomes. Therefore, therapeutic decision-making is difficult. As a major difficulty in comparing different treatment modalities for submacular hemorrhages is the lack of a standardized definition of the extent of the hemorrhage. A classification for AMD-related subretinal hemorrhages including size, thickness and intraretinal location is suggested.

  6. Retinitis Pigmentosa.

    ERIC Educational Resources Information Center

    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)

  7. Retinitis pigmentosa and retinal oedema.

    PubMed Central

    Spalton, D J; Bird, A C; Cleary, P E

    1978-01-01

    Twenty-five patients with retinitis pigmentosa and retinal leakage were investigated. Oedema was present in dominant and X-linked inherited disease and is likely to be present in recessive disease as well. We suggest that this might be a general response seen in many types of tapeto-retinal degeneration to actively degenerating photoreceptors or pigment epithelium. Images PMID:638111

  8. Obstetric hemorrhage.

    PubMed

    Clark, Steven L

    2016-03-01

    Despite the availability of potent drugs, effective surgical techniques, and extensive blood banking facilities, post-partum hemorrhage remains a major cause of death in the United States. A hemorrhage bundle developed by the New York Safe Motherhood Initiative provides clear guidelines for reducing such deaths. This bundle focuses on risk assessment, preparation, diagnosis, and the provision of several management algorithms. Implementation of the protocols and approaches contained in this document, or their equivalent, on a systems basis and a consideration of several additional recommendations for individual care will reduce the likelihood of death from hemorrhage.

  9. Subarachnoid Hemorrhage

    MedlinePlus

    ... can result from the rupture of an intracranial aneurysm — a weakened, dilated area of a blood vessel ... blood vessels in the brain even after the aneurysm that caused the hemorrhage is treated. Most of ...

  10. Retinal detachment

    PubMed Central

    2010-01-01

    Introduction Rhegmatogenous retinal detachment (RRD) is the most common form of retinal detachment, where a retinal "break" allows the ingress of fluid from the vitreous cavity to the subretinal space, resulting in retinal separation. It occurs in about 1 in 10,000 people a year. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent progression from retinal breaks or lattice degeneration to retinal detachment? What are the effects of different surgical interventions in people with rhegmatogenous retinal detachment? What are the effects of interventions to treat proliferative vitreoretinopathy occurring as a complication of retinal detachment or previous treatment for retinal detachment? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 21 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: corticosteroids, cryotherapy, daunorubicin, fluorouracil plus low molecular weight heparin, laser photocoagulation, pneumatic retinopexy, scleral buckling, short-acting or long-acting gas tamponade, silicone oil tamponade, and vitrectomy. PMID:21406128

  11. Histopathology of ultrashort-laser-pulse retinal damage

    NASA Astrophysics Data System (ADS)

    Toth, Cynthia A.; Narayan, Drew G.; Osborne, Catherine; Rockwell, Benjamin A.; Stein, Cindy D.; Amnotte, Rodney E.; DiCarlo, Cheryl D.; Roach, William P.; Noojin, Gary D.; Cain, Clarence P.

    1996-05-01

    Recent studies of retinal damage due to ultrashort laser pulses have shown interesting behavior. Laser induced retinal damage for ultrashort (i.e. less than 1 ns) laser pulses is produced at lower energies than in the nanosecond to microsecond laser pulse regime and the energy required for hemorrhagic lesions is much greater times greater for the nanosecond regime. We investigated the tissue effects exhibited in histopathology of retinal tissues exposed to ultrashort laser pulses.

  12. [Intravitreal ganciclovir in cytomegalovirus retinitis in AIDS].

    PubMed

    Olea, J L; Salvat, M; Mateos, J M; Vila, J; Villalonga, C; Riera, M

    1996-04-01

    A retrospective study was made of 26 patients with AIDS who initially presented with retinitis as the only clinical manifestation of cytomegalovirus infection (39 eyes). Sixty-five induction or re-induction therapeutic courses were administered with intravitreal ganciclovir. The efficiency rate of therapy was 93.8%. Thirty-eight maintenance therapeutic courses (200 micrograms/week) were evaluated. The non-compliance rate was 23%. Bilateral retinitis occurred in 44.4% of cases. The systemic administration of therapy had to be substituted for the intravitreal administration in 32% of patients during the clinical course of their conditions. The mean survival rate was 9.5 months. Both retinal detachment and vitreal hemorrhage occurred in 5% of patients. When retinitis is the first clinical manifestation of cytomegalovirus infection, therapy with intravitreal ganciclovir is efficacious to inactivate lesions. Although bilateral retinitis and extraocular dissemination are common, the mean survival rate is high.

  13. Retinal cartography.

    PubMed

    Mosier, M A

    1982-10-01

    This paper analyses retinal cartography in terms of its reflection of anatomic data and its relation to several forms of geographic methods of map-making. It shows that the distances between anatomic landmarks of the eye are reasonably similar to the relative distances on the retinal drawing chart currently used. Two forms of geographic cartography--azimuth equidistant and orthographic--are described and compared with retinal cartography. The retinal drawing chart currently used most closely approximates an azimuth equidistant projection, which suffers from circumferential distortion, a fact that retinal surgeons must keep in mind. It is therefore recommended that the chart be modified to have equally spaced concentric circles and clearer identification of the ora serrata; the present accurate marking of anatomic landmarks, such as the equator and the posterior border of the ciliary body, should be preserved.

  14. Dengue hemorrhagic fever

    MedlinePlus

    Hemorrhagic dengue; Dengue shock syndrome; Philippine hemorrhagic fever; Thai hemorrhagic fever; Singapore hemorrhagic fever ... and sweaty. These symptoms are followed by a shock -like state. Bleeding appears as tiny spots of ...

  15. New therapeutic modalities of retinal laser injury. Final report, 1 Mar 89-1 Mar 92

    SciTech Connect

    Lam, T.T.; Tso, M.O.

    1992-03-31

    Efficacies of three different regimens of high dose of methylprednisolone (MP) treatment on laser-induced non-hemorrhage retinal injury and tissue plasminogen activator (t-PA) in sub-retinal hemorrhage laser injury were evaluated in a sub-human primate model and a rat model respectively. Clinical, histopathological, and morphometric criteria were employed for evaluating the efficacy of MP. High dose and prolonged treatment (4 days) was the most effective regimen while high dose for 8 hours showed limited effect in non-hemorrhagic retinal injury. Intravitreal t-PA showed no apparent beneficial effect in sub-retinal hemorrhage after laser injury. Hence, patients with laser retinal injury may benefit from high dose MP treatment for an appropriate period of time.

  16. Retinal Prosthesis

    PubMed Central

    Weiland, James D.; Humayun, Mark S.

    2015-01-01

    Retinal prosthesis have been translated from the laboratory to the clinical over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa. These devices provide partial sight restoration and patients use this improved vision in their everyday lives. Improved mobility and object detection are some of the more notable findings from the clinical trials. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. This paper reviews the recent clinical trials, highlights technology breakthroughs that will contribute to next generation of retinal prostheses. PMID:24710817

  17. Retinal Disorders

    MedlinePlus

    ... be serious enough to cause blindness. Examples are Macular degeneration - a disease that destroys your sharp, central vision Diabetic eye disease Retinal detachment - a medical emergency, when the retina is ... children. Macular pucker - scar tissue on the macula Macular hole - ...

  18. Catastrophic antiphospholipid syndrome presenting as bilateral central retinal artery occlusions.

    PubMed

    Saraf, Steven S; Patel, Yogin P; Desai, Ankit; Desai, Uday R

    2015-01-01

    A previously healthy 22-year-old African American woman presented with bilateral vision loss associated with headache. Her ocular examination was significant for bilateral retinal arterial "boxcarring," retinal whitening, retinal hemorrhages, and cherry red spots. She was diagnosed with bilateral central retinal artery occlusions and was hospitalized due to concomitant diagnosis of stroke and hypercoagulable state. She was also found to be in heart failure and kidney failure. Rheumatology was consulted and she was diagnosed with catastrophic antiphospholipid syndrome in association with systemic lupus erythematosus. Approximately 7 months after presentation, the patient's vision improved and remained stable at 20/200 and 20/80. PMID:25722904

  19. [Alveolar hemorrhage].

    PubMed

    Traclet, J; Lazor, R; Cordier, J-F; Cottin, V

    2013-04-01

    Diffuse alveolar hemorrhage (DAH) is defined by the presence of red blood cells originating from the lung capillaries or venules within the alveoli. The diagnosis is established on clinical features, radiological pattern, and especially bronchoalveolar lavage. Diffuse alveolar hemorrhage may have many immune or non-immune causes. Immune causes of DAH include vasculitides, connective tissue diseases, especially systemic lupus erythematosus, and antiglomerular basement membrane antibody disease (Goodpasture's syndrome). Treatment is both supportive and causal, often based on high dose corticosteroids and immunosuppressive therapy (especially intravenous cyclophosphamide). Plasma exchanges are performed in antiglomerular basement membrane antibody disease and systemic lupus erythematosus, and are considered in systemic vasculitis. Non-immune causes of DAH mainly include heart diseases, coagulation disorders, infections, drug toxicities and idiopathic DAH. Treatment of non-immune DAH is that of its cause. Whatever the cause, DAH is an emergency requiring prompt assessment and early treatment.

  20. [Hemorrhagic enteropathy].

    PubMed

    Brobmann, G F; van Lessen, H; Springorum, H W; Thomas, C

    1976-10-21

    Intestinal infarction in the absence of organic vascular occlusion received increasing attention in recent years. The clinical picture is discussed based on results in 9 cases, an attempt to suggest a possible pathophysiological mechanism is made. Prophylactic digitalisation especially in the elderly patient in the absence of severe heart failure and in cases with already low mesenteric perfusion may lead to a further vasoconstriction and to hemorrhagic enteropathy. Therapeutic possibilities are discussed. PMID:1086816

  1. Combined branch retinal vein and artery occlusion in toxoplasmosis.

    PubMed

    Aggio, Fabio Bom; Novelli, Fernando José de; Rosa, Evandro Luis; Nobrega, Mário Junqueira

    2016-01-01

    A 22-year-old man complained of low visual acuity and pain in his left eye for five days. His ophthalmological examination revealed 2+ anterior chamber reaction and a white, poorly defined retinal lesion at the proximal portion of the inferotemporal vascular arcade. There were retinal hemorrhages in the inferotemporal region extending to the retinal periphery. In addition, venous dilation, increased tortuosity, and ischemic retinal whitening along the inferotemporal vascular arcade were also observed. A proper systemic work-up was performed, and the patient was diagnosed with ocular toxoplasmosis. He was treated with an anti-toxoplasma medication, and his condition slowly improved. Inferior macular inner and middle retinal atrophy could be observed on optical coherence tomography as a sequela of ischemic injury. To our knowledge, this is the first report of combined retinal branch vein and artery occlusion in toxoplasmosis resulting in a striking and unusual macular appearance. PMID:27463632

  2. [Cerebral hemorrhage].

    PubMed

    Nakase, Hiroyuki; Motoyama, Yasushi; Yamada, Shuichi

    2016-04-01

    Intracerebral hemorrhage (ICH) remains a serious condition for which early aggressive care is warranted. Japanese evidence-based stroke guidelines were published in 2015 to present the current and comprehensive recommendations for the diagnosis and treatment of stroke. In the spontaneous ICH, topics focused on prevention, management in the acute and chronic stage, complications, management of coagulopathy and blood pressure, prevention and control of secondary brain injury and intracranial pressure, the role of surgery, and other pathologies of ICH. The management of ICH in pregnancy and the puerperium was newly added. These guidelines provide a framework for goal-directed treatment of the patient with ICH. PMID:27333758

  3. Postpartum hemorrhage.

    PubMed

    Su, Cindy W

    2012-03-01

    Postpartum hemorrhage (PPH) is a very common obstetric emergency with high morbidity and mortality rates worldwide. Understanding its etiology is fundamental to effectively managing PPH in an acute setting. Active management of the third stage of labor is also a key component in its prevention. Management strategies include conservative measures (medications, uterine tamponade, and arterial embolization) as well as surgical interventions (arterial ligations, compression sutures, and hysterectomy). Creating a standardized PPH protocol and running simulation-based drills with a multidisciplinary team may also help decrease maternal morbidity and improve perinatal outcomes, although further studies are needed. PMID:22309588

  4. Retinal Detachment Vision Simulator

    MedlinePlus

    ... Retina Treatment Retinal Detachment Vision Simulator Retinal Detachment Vision Simulator Mar. 01, 2016 How does a detached or torn retina affect your vision? If a retinal tear is occurring, you may ...

  5. Retinal holes.

    PubMed

    Foos, R Y

    1978-09-01

    Holes of the peripheral retina, defined as full-thickness breaks of trophic origin with no associated flap or free operculum, were found in 136 (2.4%) eyes from 2,800 autopsied subjects. Primary retinal holes (those with no indication of a proximal causative lesion and with no lattice degeneration in either eye) occurred in only eight of the 5,600 eyes studied; all were unilateral, single, less than 0.25 disk diameter in size, within the basal zone, and in eyes from elderly subjects. Secondary holes were found in 128 (2.3%) of eyes and of these, lattice degeneration was the most common cause (103). Other lesions complicated by hole formation included zonular traction tufts (10), chorioretinitis (9), meridional folds (3), and pavingstone degeneration (2). Retinal holes in surgically aphakic eyes did not differ qualitatively or quantitatively from those in age-matched phakic eyes.

  6. Krypton and argon laser photocoagulation effects in subretinal hemorrhage.

    PubMed

    Chino, K; Ohki, R; Noyori, K

    1986-01-01

    Previous studies suggested that krypton laser photocoagulation was more effective in the treatment of macular diseases than argon laser. Furthermore, it could perform photocoagulation more effectively in some lesions with subretinal hemorrhage, because the krypton laser beam was poorly absorbed by hemoglobin. In the present experiment, hemorrhagic retinal detachment was produced in monkey eyes with Q-switched Nd-YAG laser, and 4 weeks later photocoagulation was performed with krypton and argon lasers to compare the differences in the effects of these two lasers. When the subretinal hemorrhage and a heavy coagulation effect was produced in the detached retina, but no coagulation effects were observed in the choroid. Krypton laser beam could go through the hemorrhage and certain coagulation effects were observed in the choroid and the detached retina. It is suggested that krypton laser photocoagulation is more effective in the lesions behind subretinal hemorrhages than photocoagulation with argon laser.

  7. Five rules to evaluate the optic disc and retinal nerve fiber layer for glaucoma.

    PubMed

    Fingeret, Murray; Medeiros, Felipe A; Susanna, Remo; Weinreb, Robert N

    2005-11-01

    A systematic approach for the examination of the optic disc and retinal nerve fiber layer is described that will aid in the detection of glaucoma. This approach encompasses 5 rules: evaluation of optic disc size, neuroretinal rim size and shape, retinal nerve fiber layer, presence of parapapillary atrophy, and presence of retinal or optic disc hemorrhages. A systematic process enhances the ability to detect glaucomatous damage as well as the detection of progression, and facilitates appropriate management. PMID:16298320

  8. Surgical management of retinal diseases: proliferative diabetic retinopathy and traction retinal detachment.

    PubMed

    Cruz-Iñigo, Yousef J; Acabá, Luis A; Berrocal, Maria H

    2014-01-01

    Current indications for pars plana vitrectomy in patients with proliferative diabetic retinopathy (PDR) include vitreous hemorrhage, tractional retinal detachment (TRD), combined tractional and rhegmatogenous retinal detachment (CTRRD), diabetic macular edema associated with posterior hyaloidal traction, and anterior segment neovascularization with media opacities. This chapter will review the indications, surgical objectives, adjunctive pharmacotherapy, microincision surgical techniques, and outcomes of diabetic vitrectomy for PDR, TRD, and CTRRD. With the availability of new microincision vitrectomy technology, wide-angle microscope viewing systems, and pharmacologic agents, vitrectomy can improve visual acuity and achieve long-term anatomic stability in eyes with severe complications from PDR.

  9. Methicillin Hemorrhagic Cystitis

    PubMed Central

    Bracis, R.; Sanders, C. V.; Gilbert, D. N.

    1977-01-01

    Interstitial nephritis is a recognized complication of methicillin therapy. Hemorrhagic cystitis due to methicillin has not been emphasized. Evidence of hemorrhagic cystitis developed in six patients receiving methicillin therapy and was confirmed by cystoscopy in three of them. PMID:907335

  10. Spontaneous absorption of extensive subinternal limiting membrane hemorrhage in shaken baby syndrome.

    PubMed

    Azzi, Tatiana Tarules; Zacharias, Leandro Cabral; Pimentel, Sérgio Luis Gianotti

    2014-01-01

    The Shaken Baby Syndrome (SBS) is characterized by subdural hematomas (SH), retinal hemorrhages (RH), and multiple fractures of long bones without external evidence of head trauma. Subinternal limiting membrane (ILM) hemorrhage, also known as macular schisis, is a characteristic finding of this entity. There is no guideline on the right time to indicate surgical treatment. This report describes an abused child with massive sub-ILM hemorrhage, which showed spontaneous absorption after less than two months of follow-up. Due to the possible spontaneous resolution, we suggest an initial conservative treatment in cases of sub-ILM hemorrhage related to SBS.

  11. Accidental human laser retinal injuries from military laser systems

    NASA Astrophysics Data System (ADS)

    Stuck, Bruce E.; Zwick, Harry; Molchany, Jerome W.; Lund, David J.; Gagliano, Donald A.

    1996-04-01

    The time course of the ophthalmoscopic and functional consequences of eight human laser accident cases from military laser systems is described. All patients reported subjective vision loss with ophthalmoscopic evidence of retinal alteration ranging from vitreous hemorrhage to retinal burn. Five of the cases involved single or multiple exposures to Q-switched neodymium radiation at close range whereas the other three incidents occur over large ranges. Most exposures were within 5 degrees of the foveola, yet none directly in the foveola. High contrast visual activity improved with time except in the cases with progressive retinal fibrosis between lesion sites or retinal hole formation encroaching the fovea. In one patient the visual acuity recovered from 20/60 at one week to 20/25 in four months with minimal central visual field loss. Most cases showed suppression of high and low spatial frequency contrast sensitivity. Visual field measurements were enlarged relative to ophthalmoscopic lesion size observations. Deep retinal scar formation and retinal traction were evident in two of the three cases with vitreous hemorrhage. In one patient, nerve fiber layer damage to the papillo-macular bundle was clearly evident. Visual performance measured with a pursuit tracking task revealed significant performance loss relative to normal tracking observers even in cases where acuity returned to near normal levels. These functional and performance deficits may reflect secondary effects of parafoveal laser injury.

  12. Branch retinal vein occlusion.

    PubMed

    Hamid, Sadaf; Mirza, Sajid Ali; Shokh, Ishrat

    2008-01-01

    Retinal vein occlusions (RVO) are the second commonest sight threatening vascular disorder. Branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) are the two basic types of vein occlusion. Branch retinal vein occlusion is three times more common than central retinal vein occlusion and- second only to diabetic retinopathy as the most common retinal vascular cause of visual loss. The origin of branch retinal vein occlusion undoubtedly includes both systemic factors such as hypertension and local anatomic factors such as arteriovenous crossings. Branch retinal vein occlusion causes a painless decrease in vision, resulting in misty or distorted vision. Current treatment options don't address the underlying aetiology of branch retinal vein occlusion. Instead they focus on treating sequelae of the occluded venous branch, such as macular oedema, vitreous haemorrhage and traction retinal detachment from neovascularization. Evidences suggest that the pathogenesis of various types of retinal vein occlusion, like many other ocular vascular occlusive disorders, is a multifactorial process and there is no single magic bullet that causes retinal vein occlusion. A comprehensive management of patients with retinal vascular occlusions is necessary to correct associated diseases or predisposing abnormalities that could lead to local recurrences or systemic event. Along with a review of the literature, a practical approach for the management of retinal vascular occlusions is required, which requires collaboration between the ophthalmologist and other physicians: general practitioner, cardiologist, internist etc. as appropriate according to each case. PMID:19385476

  13. Maternal mortality from hemorrhage.

    PubMed

    Haeri, Sina; Dildy, Gary A

    2012-02-01

    Hemorrhage remains as one of the top 3 obstetrics related causes of maternal mortality, with most deaths occurring within 24-48 hours of delivery. Although hemorrhage related maternal mortality has declined globally, it continues to be a vexing problem. More specifically, the developing world continue to shoulder a disproportionate share of hemorrhage related deaths (99%) compared with industrialized nations (1%). Given the often preventable nature of death from hemorrhage, the cornerstone of effective mortality reduction involves risk factor identification, quick diagnosis, and timely management. In this monograph we will review the epidemiology, etiology, and preventative measures related to maternal mortality from hemorrhage.

  14. Hemorrhagic Retinopathy Following Spondylosis Surgery and Seizure

    PubMed Central

    Valeshabad, Ali Kord; Francis, Andrew W.; Setlur, Vikram; Chang, Peter; Mieler, William F.; Shahidi, Mahnaz

    2015-01-01

    Purpose To report bilateral hemorrhagic retinopathy in an adult female following lumbar spinal surgery and seizure. Case Report A 38 year old female presented with bilateral blurry vision and spots in the visual field. The patient had lumbar spondylosis surgery which was complicated by a dural tear with persistent cerebrospinal fluid leak. Visual symptoms started immediately following witnessed seizure-like activity. At presentation, visual acuity was 20/100 and 20/25 in the right and left eye, respectively. Dilated fundus examination demonstrated bilateral hemorrhagic retinopathy with subhyaloid, intraretinal and subretinal involvement. At 4 month follow up, visual acuity improved to 20/60 and 20/20 in the right and left eye, respectively. Dilated fundus examination and fundus photography showed resolution of retinal hemorrhages in both eyes. Conclusions The first case of bilateral hemorrhagic retinopathy following lumbar spondylosis surgery and witnessed seizure in an adult was reported. Ophthalmic examination may be warranted following episodes of seizure in adults. PMID:26099062

  15. Hemorrhagic adrenal cyst.

    PubMed

    Cunningham, M D

    1993-05-01

    Adrenal cysts are uncommon. They may be fatal if they hemorrhage and are not rapidly diagnosed. Most adrenal cysts are small and asymptomatic. When they are symptomatic, it is usually because the cyst has enlarged, causing flank discomfort, gastrointestinal complaints, and hemorrhage. Occasionally, a palpable mass may be found. It is thought that hemorrhage occurs secondary to trauma or some toxic or infectious process. The author describes a case in which a previously healthy man had a sudden hemorrhage within a benign adrenal cyst with infarction of the kidney. A discussion of adrenal cysts follows.

  16. Retinal Vasculitis in Anti-Synthetase Syndrome.

    PubMed

    Donovan, Christopher P; Pecen, Paula E; Baynes, Kimberly; Ehlers, Justis P; Srivastava, Sunil K

    2016-09-01

    A 31-year-old woman with a history of anti-synthetase syndrome-related myositis and interstitial lung disease presented with acute-onset blurry vision and rash on her hands and feet. Visual acuity was hand motion in her right eye and 20/40 in her left eye. Dilated fundus exam showed extensive retinal vasculitis, diffuse intraretinal hemorrhages, and subretinal fluid. Optical coherence tomography revealed significant macular thickening, and fluorescein angiography revealed vascular leakage with peripheral nonperfusion. Aggressive systemic immunosuppression was initiated, with gradual resolution of her disease during 8 months of follow-up. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:874-879.].

  17. Retinal Vasculitis in Anti-Synthetase Syndrome.

    PubMed

    Donovan, Christopher P; Pecen, Paula E; Baynes, Kimberly; Ehlers, Justis P; Srivastava, Sunil K

    2016-09-01

    A 31-year-old woman with a history of anti-synthetase syndrome-related myositis and interstitial lung disease presented with acute-onset blurry vision and rash on her hands and feet. Visual acuity was hand motion in her right eye and 20/40 in her left eye. Dilated fundus exam showed extensive retinal vasculitis, diffuse intraretinal hemorrhages, and subretinal fluid. Optical coherence tomography revealed significant macular thickening, and fluorescein angiography revealed vascular leakage with peripheral nonperfusion. Aggressive systemic immunosuppression was initiated, with gradual resolution of her disease during 8 months of follow-up. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:874-879.]. PMID:27631486

  18. Massive choroidal hemorrhage associated with low molecular weight heparin therapy.

    PubMed

    Neudorfer, M; Leibovitch, I; Goldstein, M; Loewenstein, A

    2002-04-01

    An 84-year-old woman with unstable angina pectoris was treated with subcutaneous enoxaparine (Clexane) for several days before presenting with severe pain and decreased vision in her left eye. The intraocular pressure was 70 mmHg, and fundus examination showed a pigmented choroidal lesion and associated choroidal and retinal detachment. Ultrasonography was consistent with choroidal hemorrhage, and she was diagnosed as having acute glaucoma secondary to massive subchoroidal hemorrhage. Medical control of the intraocular pressure resulted in a significant clinical improvement. Intraocular hemorrhage and angle-closure glaucoma are rare and previously unreported complications in patients treated with low molecular weight heparin. It is important to be aware of this ocular complication as these drugs are so often used. PMID:11943940

  19. Retinal remodeling in human retinitis pigmentosa.

    PubMed

    Jones, B W; Pfeiffer, R L; Ferrell, W D; Watt, C B; Marmor, M; Marc, R E

    2016-09-01

    Retinitis Pigmentosa (RP) in the human is a progressive, currently irreversible neural degenerative disease usually caused by gene defects that disrupt the function or architecture of the photoreceptors. While RP can initially be a disease of photoreceptors, there is increasing evidence that the inner retina becomes progressively disorganized as the outer retina degenerates. These alterations have been extensively described in animal models, but remodeling in humans has not been as well characterized. This study, using computational molecular phenotyping (CMP) seeks to advance our understanding of the retinal remodeling process in humans. We describe cone mediated preservation of overall topology, retinal reprogramming in the earliest stages of the disease in retinal bipolar cells, and alterations in both small molecule and protein signatures of neurons and glia. Furthermore, while Müller glia appear to be some of the last cells left in the degenerate retina, they are also one of the first cell classes in the neural retina to respond to stress which may reveal mechanisms related to remodeling and cell death in other retinal cell classes. Also fundamentally important is the finding that retinal network topologies are altered. Our results suggest interventions that presume substantial preservation of the neural retina will likely fail in late stages of the disease. Even early intervention offers no guarantee that the interventions will be immune to progressive remodeling. Fundamental work in the biology and mechanisms of disease progression are needed to support vision rescue strategies. PMID:27020758

  20. SURGICAL EMBOLECTOMY FOR FOVEA-THREATENING ACUTE RETINAL ARTERY OCCLUSION

    PubMed Central

    Almeida, David R.P.; Mammo, Zaid; Chin, Eric K.

    2016-01-01

    Purpose: To describe a technique of surgical intraocular embolectomy in patients with acute fovea-threatening branch retinal artery occlusion. Methods: Pars plana vitrectomy with embolectomy involving embolus isolation, dissection, and removal in patients with an acute fovea-threatening arterial occlusion without a patent cilioretinal artery. Results: The surgical technique involves a core vitrectomy. The blocked artery is incised using a microvitreoretinal blade, and microsurgical forceps are used to retrieve the embolus. No significant complications were noted. The study technique offers an excellent safety profile and minimizes the risk of vitreous hemorrhage by carefully dissecting the vascular adventitial sheath and isolating the embolus. Conclusion: Surgical embolectomy is a viable technique for patients with acute fovea-threatening arterial occlusions without patent cilioretinal artery. Careful dissection and retrieval of the embolus minimizes the risk of vitreous hemorrhage, which is an important improvement in previous techniques for management of acute retinal arterial occlusions. PMID:26674278

  1. Genetics Home Reference: retinitis pigmentosa

    MedlinePlus

    ... Me Understand Genetics Home Health Conditions retinitis pigmentosa retinitis pigmentosa Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Retinitis pigmentosa is a group of related eye disorders that ...

  2. Microwave hemorrhagic stroke detector

    DOEpatents

    Haddad, Waleed S.; Trebes, James E.

    2007-06-05

    The microwave hemorrhagic stroke detector includes a low power pulsed microwave transmitter with a broad-band antenna for producing a directional beam of microwaves, an index of refraction matching cap placed over the patients head, and an array of broad-band microwave receivers with collection antennae. The system of microwave transmitter and receivers are scanned around, and can also be positioned up and down the axis of the patients head. The microwave hemorrhagic stroke detector is a completely non-invasive device designed to detect and localize blood pooling and clots or to measure blood flow within the head or body. The device is based on low power pulsed microwave technology combined with specialized antennas and tomographic methods. The system can be used for rapid, non-invasive detection of blood pooling such as occurs with hemorrhagic stoke in human or animal patients as well as for the detection of hemorrhage within a patient's body.

  3. Microwave hemorrhagic stroke detector

    DOEpatents

    Haddad, Waleed S.; Trebes, James E.

    2002-01-01

    The microwave hemorrhagic stroke detector includes a low power pulsed microwave transmitter with a broad-band antenna for producing a directional beam of microwaves, an index of refraction matching cap placed over the patients head, and an array of broad-band microwave receivers with collection antennae. The system of microwave transmitter and receivers are scanned around, and can also be positioned up and down the axis of the patients head. The microwave hemorrhagic stroke detector is a completely non-invasive device designed to detect and localize blood pooling and clots or to measure blood flow within the head or body. The device is based on low power pulsed microwave technology combined with specialized antennas and tomographic methods. The system can be used for rapid, non-invasive detection of blood pooling such as occurs with hemorrhagic stroke in human or animal patients as well as for the detection of hemorrhage within a patient's body.

  4. Hereditary Hemorrhagic Telangiectasia - HHT

    MedlinePlus

    ... Throughout Body Hereditary Hemorrhagic Telangiectasia (HHT) is a genetic disorder that affects about one in 5,000 people and causes arterial blood to flow directly into the veins, creating weakened ballooned vessels that can rupture. Interventional radiologists ...

  5. Ebola hemorrhagic Fever.

    PubMed

    Burnett, Mark W

    2014-01-01

    Ebola hemorrhagic fever is an often-fatal disease caused by a virus of the Filoviridae family, genus Ebolavirus. Initial signs and symptoms of the disease are nonspecific, often progressing on to a severe hemorrhagic illness. Special Operations Forces Medical Providers should be aware of this disease, which occurs in sporadic outbreaks throughout Africa. Treatment at the present time is mainly supportive. Special care should be taken to prevent contact with bodily fluids of those infected, which can transmit the virus to caregivers.

  6. Thrombin induces Sp1-mediated antiviral effects in cytomegalovirus-infected human retinal pigment epithelial cells.

    PubMed

    Scholz, Martin; Vogel, Jens-Uwe; Höver, Gerold; Prösch, Susanna; Kotchetkov, Ruslan; Cinatl, Jaroslav; Koch, Frank; Doerr, Hans Wilhelm; Cinatl, Jindrich

    2004-11-01

    Human cytomegalovirus (HCMV) retinitis causing retinal detachment and destruction of the blood-retina barrier is closely related to retinal hemorrhage/coagulation. However, the effects of procoagulants on HCMV (re)activation in retinal cells have not been investigated yet. Therefore, we studied whether thrombin modulates the expression of HCMV immediate early (IE) and late (L) genes in cultured human retinal pigment epithelial cells (RPE). Thrombin specifically stimulated the protease-activated receptor-1 (PAR-1) on RPE and, surprisingly, inhibited basal and 12,0-tetradecanoylphorbol 13-acetate-stimulated HCMV IE gene expression in infected RPE. On the other hand, HCMV strongly induced Sp1 DNA binding activity, which was prevented by thrombin/PAR1-mediated Sp1 hyperphosphorylation. Our data suggest that thrombin/PAR-1 may inhibit Sp1-dependent HCMV replication, which might be an important regulatory mechanism for HCMV persistence and replication in RPE.

  7. Modern retinal laser therapy.

    PubMed

    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

  8. Automated detection of retinal whitening in malarial retinopathy

    NASA Astrophysics Data System (ADS)

    Joshi, V.; Agurto, C.; Barriga, S.; Nemeth, S.; Soliz, P.; MacCormick, I.; Taylor, T.; Lewallen, S.; Harding, S.

    2016-03-01

    Cerebral malaria (CM) is a severe neurological complication associated with malarial infection. Malaria affects approximately 200 million people worldwide, and claims 600,000 lives annually, 75% of whom are African children under five years of age. Because most of these mortalities are caused by the high incidence of CM misdiagnosis, there is a need for an accurate diagnostic to confirm the presence of CM. The retinal lesions associated with malarial retinopathy (MR) such as retinal whitening, vessel discoloration, and hemorrhages, are highly specific to CM, and their detection can improve the accuracy of CM diagnosis. This paper will focus on development of an automated method for the detection of retinal whitening which is a unique sign of MR that manifests due to retinal ischemia resulting from CM. We propose to detect the whitening region in retinal color images based on multiple color and textural features. First, we preprocess the image using color and textural features of the CMYK and CIE-XYZ color spaces to minimize camera reflex. Next, we utilize color features of the HSL, CMYK, and CIE-XYZ channels, along with the structural features of difference of Gaussians. A watershed segmentation algorithm is used to assign each image region a probability of being inside the whitening, based on extracted features. The algorithm was applied to a dataset of 54 images (40 with whitening and 14 controls) that resulted in an image-based (binary) classification with an AUC of 0.80. This provides 88% sensitivity at a specificity of 65%. For a clinical application that requires a high specificity setting, the algorithm can be tuned to a specificity of 89% at a sensitivity of 82%. This is the first published method for retinal whitening detection and combining it with the detection methods for vessel discoloration and hemorrhages can further improve the detection accuracy for malarial retinopathy.

  9. Advantages of diabetic tractional retinal detachment repair

    PubMed Central

    Sternfeld, Amir; Axer-Siegel, Ruth; Stiebel-Kalish, Hadas; Weinberger, Dov; Ehrlich, Rita

    2015-01-01

    Purpose To evaluate the outcomes and complications of patients with diabetic tractional retinal detachment (TRD) treated with pars plana vitrectomy (PPV). Patients and methods We retrospectively studied a case series of 24 eyes of 21 patients at a single tertiary, university-affiliated medical center. A review was carried out on patients who underwent PPV for the management of TRD due to proliferative diabetic retinopathy from October 2011 to November 2013. Preoperative and final visual outcomes, intraoperative and postoperative complications, and medical background were evaluated. Results A 23 G instrumentation was used in 23 eyes (95.8%), and a 25 G instrumentation in one (4.2%). Mean postoperative follow-up time was 13.3 months (4–30 months). Visual acuity significantly improved from logarithm of the minimum angle of resolution (LogMAR) 1.48 to LogMAR 1.05 (P<0.05). Visual acuity improved by ≥3 lines in 75% of patients. Intraoperative complications included iatrogenic retinal breaks in seven eyes (22.9%) and vitreal hemorrhage in nine eyes (37.5%). In two eyes, one sclerotomy was enlarged to 20 G (8.3%). Postoperative complications included reoperation in five eyes (20.8%) due to persistent subretinal fluid (n=3), vitreous hemorrhage (n=1), and dislocated intraocular lens (n=1). Thirteen patients (54.2%) had postoperative vitreous hemorrhage that cleared spontaneously, five patients (20.8%) required antiglaucoma medications for increased intraocular pressure, seven patients (29.2%) developed an epiretinal membrane, and two patients (8.3%) developed a macular hole. Conclusion Patients with diabetic TRD can benefit from PPV surgery. Intraoperative and postoperative complications can be attributed to the complexity of this disease. PMID:26604667

  10. Luminosity and contrast normalization in color retinal images based on standard reference image

    NASA Astrophysics Data System (ADS)

    S. Varnousfaderani, Ehsan; Yousefi, Siamak; Belghith, Akram; Goldbaum, Michael H.

    2016-03-01

    Color retinal images are used manually or automatically for diagnosis and monitoring progression of a retinal diseases. Color retinal images have large luminosity and contrast variability within and across images due to the large natural variations in retinal pigmentation and complex imaging setups. The quality of retinal images may affect the performance of automatic screening tools therefore different normalization methods are developed to uniform data before applying any further analysis or processing. In this paper we propose a new reliable method to remove non-uniform illumination in retinal images and improve their contrast based on contrast of the reference image. The non-uniform illumination is removed by normalizing luminance image using local mean and standard deviation. Then the contrast is enhanced by shifting histograms of uniform illuminated retinal image toward histograms of the reference image to have similar histogram peaks. This process improve the contrast without changing inter correlation of pixels in different color channels. In compliance with the way humans perceive color, the uniform color space of LUV is used for normalization. The proposed method is widely tested on large dataset of retinal images with present of different pathologies such as Exudate, Lesion, Hemorrhages and Cotton-Wool and in different illumination conditions and imaging setups. Results shows that proposed method successfully equalize illumination and enhances contrast of retinal images without adding any extra artifacts.

  11. Retinal and optic nerve diseases.

    PubMed

    Margalit, Eyal; Sadda, Srinivas R

    2003-11-01

    A variety of disease processes can affect the retina and/or the optic nerve, including vascular or ischemic disease, inflammatory or infectious disease, and degenerative disease. These disease processes may selectively damage certain parts of the retina or optic nerve, and the specific areas that are damaged may have implications for the design of potential therapeutic visual prosthetic devices. Outer retinal diseases include age-related macular degeneration, pathologic myopia, and retinitis pigmentosa. Although the retinal photoreceptors may be lost, the inner retina is relatively well-preserved in these diseases and may be a target for retinal prosthetic devices. Inner retinal diseases include retinal vascular diseases such as diabetic retinopathy, retinal venous occlusive disease, and retinopathy of prematurity. Other retinal diseases such as ocular infections (retinitis, endophthalmitis) may affect all retinal layers. Because the inner retinal cells, including the retinal ganglion cells, may be destroyed in these diseases (inner retinal or whole retinal), prosthetic devices that stimulate the inner retina may not be effective. Common optic nerve diseases include glaucoma, optic neuritis, and ischemic optic neuropathy. Because the ganglion cell nerve fibers themselves are damaged, visual prosthetics for these diseases will need to target more distal portions of the visual pathway, such as the visual cortex. Clearly, a sound understanding of retinal and optic nerve disease pathophysiology is critical for designing and choosing the optimal visual prosthetic device.

  12. Evaluation of retinal laser lesion healing by perimetric electroretinography

    NASA Astrophysics Data System (ADS)

    Schmeisser, Elmar T.

    1996-04-01

    Eight Cynomolgus fasciculata who had graded laser lesions placed in one eye 6 years previously were evaluated by a stimulation and electrophysiologic recording technique to produce maps of retinal function. All animal testing was performed under IACUC approved protocols. The single q-switched pulses from a neodymium-YAG laser produced lesions of 4 types: no visible change, minimal visible lesions, `white dot' lesions (localized circumscribed retinal blanching) and `red dot' lesions (contained retinal hemorrhage) in the eye at the time of placement. Single exposures had been made in four locations: 5 degrees superior, inferior and temporal to the fovea, and one foveally. The multifocal (perimetric) electroretinogram was recorded from specialized contact lenses through hospital grade amplifiers. Initial analyses gave field maps that demonstrated apparent relative loss of function in some lesion sites. However, these losses were variable and occasionally patchy (i.e. disconnected areas of low signal). Repeated examinations of the same retinal areas showed high variability, even with 15 minute acquisition times and no apparent gaze drift. Apparent losses did not appear to correlate with visible retinal changes at the lesion site. Further research is needed to determine the biological substrate for this variability in response topography.

  13. Pontine infarcts and hemorrhages.

    PubMed

    Moncayo, Jorge

    2012-01-01

    Pontine infarcts are often part of a large ischemia involving the brainstem, although infarcts may be restricted to the pons. In both cases, infarcts in the pons are characterized by interesting clinical patterns resulting from a variety of cranial nerve dysfunctions, eye movement disorders and motor, sensory and cerebellar manifestations, either isolated or in combination. The anteromedial and anterolateral territories are the most commonly involved. Penetrating branch artery disease is the most common etiology. Ten percent of all intracerebral hemorrhages are located in the pons, and small hemorrhages in this brainstem structure may, in some instances, give rise to unusual clinical manifestations. PMID:22377887

  14. Subarachnoid Hemorrhage: An Update.

    PubMed

    Dority, Jeremy S; Oldham, Jeffrey S

    2016-09-01

    Subarachnoid hemorrhage (SAH) is a debilitating, although uncommon, type of stroke with high morbidity, mortality, and economic impact. Modern 30-day mortality is as high as 40%, and about 50% of survivors have permanent disability. Care at high-volume centers with dedicated neurointensive care units is recommended. Euvolemia, not hypervolemia, should be targeted, and the aneurysm should be secured early. Neither statin therapy nor magnesium infusions should be initiated for delayed cerebral ischemia. Cerebral vasospasm is just one component of delayed cerebral edema. Hyponatremia is common in subarachnoid hemorrhage and is associated with longer length of stay, but not increased mortality. PMID:27521199

  15. Hereditary Hemorrhagic Telangiectasia.

    PubMed

    Parambil, Joseph G

    2016-09-01

    Hereditary hemorrhagic telangiectasia (HHT) is an underrecognized and underdiagnosed autosomal-dominant angiodysplasia that has an estimated prevalence of 1 in 5000 individuals, with variable clinical presentations even within family members with identical mutations. The most common manifestations are telangiectasias of the skin and nasal mucosa. However, HHT can often be complicated by the presence of arteriovenous malformations and telangiectasias in the lungs, brain, gastrointestinal tract, and liver that are often silent and can lead to life-threatening complications of stroke and hemorrhage. This article reviews HHT for the pulmonologist, who is not uncommonly the first practitioner to encounter these patients. PMID:27514597

  16. Retinal vein occlusion

    MedlinePlus

    ... most often caused by hardening of the arteries ( atherosclerosis ) and the formation of a blood clot. Blockage ... arteries that have been thickened or hardened by atherosclerosis cross over and place pressure on a retinal ...

  17. Retinal artery occlusion

    MedlinePlus

    ... eds. Textbook of Family Medicine . 9th ed. Philadelphia, PA: Elsevier; 2016:chap 17. Duker JS. Retinal arterial ... M, Duker JS, eds. Ophthalmology. 4th ed. Philadelphia, PA: Elsevier; 2014:chap 6.18. Reiss GR, Sipperley ...

  18. The Use of Ophthalmic Ultrasonography to Identify Retinal Injuries Associated With Abusive Head Trauma.

    PubMed

    Riggs, Becky J; Trimboli-Heidler, Carmelina; Spaeder, Michael C; Miller, Marijean M; Dean, Nathan P; Cohen, Joanna S

    2016-05-01

    Abusive head trauma includes any nonaccidental injury inflicted to a child's head and body. It is often characterized by, but not limited to, the repetitive acceleration-deceleration forces with or without blunt head impact. It has a mortality rate of 30%, and 80% of survivors experience permanent neurologic damage. In this case series, we hypothesize that bedside ultrasonography can be useful in the identification of retinal injuries that are consistent with abusive head trauma. Ocular manifestations of abusive head trauma are identified by dilated ophthalmic examination showing retinal hemorrhages that are too numerous to count, multilayered, and extending to the periphery. Traumatic retinoschisis, splitting of the retinal layers with or without blood accumulating in the intervening space, is exclusive for abusive head trauma in infants without a history of significant cerebral crush injury. Direct visualization of intraocular structures is difficult when the eyelids are swollen shut or when dilatation must be delayed. We present a series of 11 patients with brain injuries who underwent ophthalmic point-of-care ultrasonography that revealed traumatic retinoschisis on average 60 hours earlier than direct ophthalmic visualization. Dilated ophthalmic examinations and autopsy reports confirmed retinoschisis and other forms of retinal hemorrhages that were too numerous to count, multilayered, and extending to the periphery in all 11 patients. One patient did not have a dilated ophthalmic examination; however, traumatic retinoschisis and retinal hemorrhages were confirmed on autopsy. Ocular point-of-care ultrasonography is a promising tool to investigate abusive head trauma through the identification of traumatic retinoschisis and retinal hemorrhages when pupillary dilatation and direct ophthalmic examination is delayed.

  19. Retinal detachment in pseudophakia.

    PubMed

    Galin, M A; Poole, T A; Obstbaum, S A

    1979-07-01

    In a series of cataract patients excluding myopic individuals, under age 60 years, and cases in which vitreous loss occurred, retinal detachment was no less frequent after intracapsular cataract extraction and Sputnik iris supported lenses than in controls. Both groups were followed up for a minimum of two years. The detachments predominantly occurred from retinal breaks in areas of the retina that looked normal preoperatively. PMID:464014

  20. Progressive outer retinal necrosis-like retinitis in immunocompetent hosts.

    PubMed

    Chawla, Rohan; Tripathy, Koushik; Gogia, Varun; Venkatesh, Pradeep

    2016-01-01

    We describe two young immunocompetent women presenting with bilateral retinitis with outer retinal necrosis involving posterior pole with centrifugal spread and multifocal lesions simulating progressive outer retinal necrosis (PORN) like retinitis. Serology was negative for HIV and CD4 counts were normal; however, both women were on oral steroids at presentation for suspected autoimmune chorioretinitis. The retinitis in both eyes responded well to oral valaciclovir therapy. However, the eye with the more fulminant involvement developed retinal detachment with a loss of vision. Retinal atrophy was seen in the less involved eye with preservation of vision. Through these cases, we aim to describe a unique evolution of PORN-like retinitis in immunocompetent women, which was probably aggravated by a short-term immunosuppression secondary to oral steroids. PMID:27511757

  1. Progressive outer retinal necrosis-like retinitis in immunocompetent hosts.

    PubMed

    Chawla, Rohan; Tripathy, Koushik; Gogia, Varun; Venkatesh, Pradeep

    2016-08-10

    We describe two young immunocompetent women presenting with bilateral retinitis with outer retinal necrosis involving posterior pole with centrifugal spread and multifocal lesions simulating progressive outer retinal necrosis (PORN) like retinitis. Serology was negative for HIV and CD4 counts were normal; however, both women were on oral steroids at presentation for suspected autoimmune chorioretinitis. The retinitis in both eyes responded well to oral valaciclovir therapy. However, the eye with the more fulminant involvement developed retinal detachment with a loss of vision. Retinal atrophy was seen in the less involved eye with preservation of vision. Through these cases, we aim to describe a unique evolution of PORN-like retinitis in immunocompetent women, which was probably aggravated by a short-term immunosuppression secondary to oral steroids.

  2. Photovoltaic retinal prosthesis

    NASA Astrophysics Data System (ADS)

    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.

  3. Prohemostatic interventions in obstetric hemorrhage.

    PubMed

    Bonnet, Marie-Pierre; Basso, Olga

    2012-04-01

    Obstetric hemorrhage is a major cause of maternal morbidity and mortality. Pregnancy is associated with substantial hemostatic changes, resulting in a relatively hypercoagulable state. Acquired coagulopathy can, however, develop rapidly in severe obstetric hemorrhage. Therefore, prohemostatic treatments based on high fresh frozen plasma and red blood cell (FFP:RBC) ratio transfusion and procoagulant agents (fibrinogen concentrates, recombinant activated factor VII, and tranexamic acid) are crucial aspects of management. Often, evidence from trauma patients is applied to obstetric hemorrhage management, although distinct differences exist between the two situations. Therefore, until efficacy and safety are demonstrated in obstetric hemorrhage, clinicians should be cautious about wholesale adoption of high FFP:RBC ratio products. Applications of transfusion protocols, dedicated to massive obstetric hemorrhage and multidisciplinarily developed, currently remain the best available option. Similarly, while procoagulant agents appear promising in treatment of obstetric hemorrhage, caution is nonetheless warranted as long as clear evidence in the context of obstetric hemorrhage is lacking. PMID:22510859

  4. Diabeteslike preproliferative retinal changes in galactose-fed dogs.

    PubMed

    Takahashi, Y; Wyman, M; Ferris, F; Kador, P F

    1992-09-01

    Retinal vessel changes were experimentally investigated by a combination of color fundus photography, fluorescein angiography, and histologic studies in beagles that were fed a 30% galactose diet for up to 66 months. Previously, we have described the appearance of pericyte ghosts, microaneurysms, acellular capillaries, and intraretinal hemorrhages in dogs fed a galactose diet for up to 36 months. These disorders were similar to those observed in humans with background diabetic retinopathy. We report herein that dogs fed galactose for 48 to 60 months experience retinal changes associated with the chronic occlusion of capillary beds and subsequent ischemia of the retina. These changes included the appearance of broad areas of nonperfusion, soft exudates (cytoid bodies), intraretinal microvascular abnormalities, occluded arterioles, preretinal and intravitreal hemorrhages, and apparent new vessel growth around the optic disc. The present study clearly demonstrates that the galactose-fed dog is an animal model in which advanced retinal changes develop, and these changes are similar to those associated with preproliferative human diabetic retinopathy.

  5. Delayed Consecutive Contralateral Thalamic Hemorrhage after Spontaneous Thalamic Hemorrhage

    PubMed Central

    Han, Ji Hun; Choi, Hyuk Jai; Yang, Jin Seo; Kang, Suk Hyung; Cho, Yong Jun

    2016-01-01

    Simultaneous or subsequent bilateral thalamic hemorrhagic events have ranged from 12 to 19 in prior reports, with a time lag between bilateral thalamic hemorrhage of up to two days. Herein, we report the first case of delayed (17 days) consecutive contralateral thalamic hemorrhage after spontaneous first thalamic hemorrhage. A 65-year-old female initially presented with a drowsy mentality with a left-side motor weakness (grade II/III). Brain computed tomography (CT) demonstrated right side thalamic and intraventricular hemorrhage. She regained alertness with mild residual motor weakness (grade III/IV) under medical management. Seventeen days later, a sudden and generalized tonic-clonic seizure developed. Brain CT scans revealed a new contralateral thalamic hemorrhage coincident with microbleeds. Neurologic status remained unchanged, consisting of a stuporous mentality with quadriparesis of grade II/II. We report the first case of delayed consecutive contralateral thalamic hemorrhage up to 17 days after first thalamic hemorrhage. The case highlights the need for close monitoring of patients with thalamic hemorrhage who experience microbleeds on the contralateral side, due to the possibility of delayed hemorrhage.

  6. Retinal pigment epithelial cell proliferation

    PubMed Central

    Temple, Sally

    2015-01-01

    The human retinal pigment epithelium forms early in development and subsequently remains dormant, undergoing minimal proliferation throughout normal life. Retinal pigment epithelium proliferation, however, can be activated in disease states or by removing retinal pigment epithelial cells into culture. We review the conditions that control retinal pigment epithelial proliferation in culture, in animal models and in human disease and interpret retinal pigment epithelium proliferation in context of the recently discovered retinal pigment epithelium stem cell that is responsible for most in vitro retinal pigment epithelial proliferation. Retinal pigment epithelial proliferation-mediated wound repair that occurs in selected macular diseases is contrasted with retinal pigment epithelial proliferation-mediated fibroblastic scar formation that underlies proliferative vitreoretinopathy. We discuss the role of retinal pigment epithelial proliferation in age-related macular degeneration which is reparative in some cases and destructive in others. Macular retinal pigment epithelium wound repair and regression of choroidal neovascularization are more pronounced in younger than older patients. We discuss the possibility that the limited retinal pigment epithelial proliferation and latent wound repair in older age-related macular degeneration patients can be stimulated to promote disease regression in age-related macular degeneration. PMID:26041390

  7. Probabilistic retinal vessel segmentation

    NASA Astrophysics Data System (ADS)

    Wu, Chang-Hua; Agam, Gady

    2007-03-01

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

  8. Bioelectronic retinal prosthesis

    NASA Astrophysics Data System (ADS)

    Weiland, James D.

    2016-05-01

    Retinal prosthesis have been translated to clinical use over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa and one device is in clinical trials for treatment of age-related macular degeneration. These devices provide partial sight restoration and patients use this improved vision in their everyday lives to navigate and to detect large objects. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. In particular, current retinal prostheses do not provide peripheral visions due to technical and surgical limitations, thus limiting the effectiveness of the treatment. This paper reviews recent results from human implant patients and presents technical approaches for peripheral vision.

  9. Bilateral macular hemorrhage due to megaloblastic anemia: A rare case report

    PubMed Central

    Vaggu, Sree Kumar; Bhogadi, Preethi

    2016-01-01

    We report a case of a 17-year-old female patient who presented with sudden, painless, nonprogressive diminished vision in both eyes (best corrected visual acuity in right eye - 6/60 and left eye - 6/36). An ophthalmological evaluation revealed bilateral pale tarsal conjunctiva and bilateral macular hemorrhage. Hematological evaluation revealed the presence of megalocytic anemia (with hemoglobin - 4.9 g%). General examination showed severe pallor. On systemic examination, no abnormality was detected, confirmed by ultrasonography abdomen. Other causes. This case documents the rare occurrence of bilateral subinternal limiting membrane macular hemorrhage with megaloblastic anemia without thrombocytopenia and other retinal features of anemic retinopathy. PMID:27050355

  10. Hemorrhagic cerebrovascular disease.

    PubMed

    Romero, Javier M; Rosand, Jonathan

    2016-01-01

    Primary or nontraumatic spontaneous intracerebral hemorrhage (ICH) accounts for 10-15% of all strokes, and has a poor prognosis. ICH has a mortality rate of almost 50% when associated with intraventricular hemorrhage within the first month, and 80% rate of dependency at 6 months from onset. Neuroimaging is critical in identifying the underlying etiology and thus assisting in the important therapeutic decisions. There are several imaging modalities available in the workup of patients who present with ICH, including computed tomography (CT), magnetic resonance imaging (MRI), and digital subtraction angiography (DSA). A review of the current imaging approach, as well as a differential diagnosis of etiologies and imaging manifestations of primary versus secondary intraparenchymal hemorrhage, is presented. Active bleeding occurs in the first hours after symptom onset, with early neurologic deterioration. Identifying those patients who are more likely to have hematoma expansion is an active area of research, and there are many ongoing therapeutic trials targeting this specific patient population at risk. PMID:27432674

  11. Pathway to Retinal Oximetry

    PubMed Central

    Beach, James

    2014-01-01

    Events and discoveries in oxygen monitoring over the past two centuries are presented as the background from which oximetry of the human retina evolved. Achievements and the people behind them are discussed, showing parallels between the work in tissue measurements and later in the eye. Developments in the two-wavelength technique for oxygen saturation measurements in retinal vessels are shown to exploit the forms of imaging technology available over time. The last section provides a short summary of the recent research in retinal diseases using vessel oximetry. PMID:25237591

  12. [Hemorrhagic stroke associated to neurocysticercosis].

    PubMed

    Tellez-Zenteno, J F; Negrete-Pulido, O; Cantú, C; Márquez, C; Vega-Boada, F; García Ramos, G

    2003-06-01

    A well-known complication of neurocysticercosis is cerebral arteritis, which is usually manifested by cerebral ischemia. Only anecdotal cases of hemorrhagic stroke associated to this parasitosis have been described. Previously there are only two reported cases of this association. One of these cases had an intracystic hemorrhage confirmed by autopsy without cerebrovascular risk factors. Autopsy revealed an inflammatory arteriopathy adjacent to the cyst intracystic hemorrhage. The second case had a subarachnoidal hemorrhage secondary to the rupture of an aneurysm in the right anteroinferior cerebellar artery. At surgery, the aneurysm was found to be surrounded by a thickened-leptomeninges, which histologically showed the presence of cysticercous with dense inflammation. Our first patient was a 32 year-old female developed a lenticulo-capsular hemorrhage around a cysticercotic lesion. The second patient was a 34 year-old male developed an intracystic hemorrhage. As cerebral angiography was normal in both patients, cerebral hemorrhages were considered to be related to cysticercotic arteritis of small penetrating vessels. We conclude that cysticercosis is associated with differenttypes of intracranial hemorrhage, as documented the present cases. In neurocysticercosis endemic areas, cysticercotic arteritis should be added to the list of causes of intracranial hemorrhage in young people. PMID:12768515

  13. Nanomaterials and Retinal Toxicity

    EPA Science Inventory

    The neuroretina should be considered as a potential site of nanomaterial toxicity. Engineered nanomaterials may reach the retina through three potential routes of exposure including; intra­ vitreal injection of therapeutics; blood-borne delivery in the retinal vasculature an...

  14. Degenerative retinal disorders

    SciTech Connect

    Hollyfield, J.G. Anderson, R.E. LaVail, M.M. . Dept. of Anatomy)

    1987-01-01

    This book contains papers divided among three sections. Some of the paper titles are: Molecular Genetics of Gyrate Atrophy; Molecular Site of Expression and Genetic Interaction of the rd and the rds Loci in the Retina of the Mouse; and Studies on Abnormal Cyclic GMP Metabolism in Animal Models of Retinal Degeneration: Genetic Relationships and Cellular Compartmentalization.

  15. Dengue hemorrhagic fever.

    PubMed

    Rosen, L

    1996-01-01

    Dengue has been known for more than 200 years. The first dengue viruses were isolated about 50 years ago. Prior to the 1950's, dengue was considered a mild febrile disease, though rare hemorrhagic and fatal cases were known to occur. After that date, the first epidemics of dengue hemorrhagic fever (DHF) appeared in Southeast Asia, and DHF became the most important cause of childhood morbidity and mortality in the region. The emergence of DHF epidemics was first explained by mutations affecting dengue viruses, making them more virulent, but this hypothesis was not retained. Then, the "secondary infection" or "immune enhancement" theory was proposed to explain the increased virulence of dengue viruses when children had a secondary infection. This second hypothesis is still actually favoured. However, observations in Southeast Asia, some Pacific islands, and Americas do not agree with the "secondary infection" hypothesis, which consequently has been modified several times. Recent advances in molecular biology have led to the recognition that some viral strains are more virulent than others. Another hypothesis is the selection of more virulent dengue strains by the new vector Ae. aegypti, replacing the local vector Ae. albopictus, when urbanization and modern transportation increased in Southeast Asia after the last war. Comparisons between epidemics are very difficult, because of the distinction between DHF cases according to WHO criteria and dengue fever (DF) cases with hemorrhages. This distinction has no pathogenic or prognostic grounds, and makes the task of clinicians more difficult. The actual situation in countries facing dengue epidemics makes clear that this disease will continue to be a public health problem for some time to come.

  16. Experimental Application of Piezoelectric Actuator-Driven Pulsed Water Jets in Retinal Vascular Surgery

    PubMed Central

    Kunikata, Hiroshi; Tanaka, Yuji; Aizawa, Naoko; Nakagawa, Atsuhiro; Tominaga, Teiji; Nakazawa, Toru

    2014-01-01

    Purpose To report on the effectiveness and safety of an ophthalmic piezoelectric actuator-driven pulsed water jet (ADPJ) system adapted for intraocular use. Methods First, we determined the highest ADPJ flow rate that did not cause an unsafe rise in intraoperative intraocular pressure (IOP) in rabbits (n = 4). Next, we determined the most effective ADPJ frequency (in hertz) at that flow rate. Finally, we visualized the ADPJ stream, measured its pressure, and determined the minimum voltage and distance between the ADPJ needle and retinal veins to induce intravenous displacement of the blood column (DBC) through massage of the outer retinal vessels (n = 3) while not causing retinal tearing or hemorrhage. Results We found that a 0.05 mL/min ADPJ flow rate caused IOP to rise above 40 mm Hg after 1 minute, but that at 0.025 mL/min, IOP stayed below 40 mm Hg even after 3 minutes. Moreover, we found that a 0.025 mL/min ADPJ stream was stable at a pulse frequency of 10 Hz and that at this flow rate/frequency the ADPJ pressure was closely correlated with the applied voltage (P < 0.001, r2 = 0.9991). The minimum voltage and distance to achieve intravenous DBC without causing retinal tearing or hemorrhage were 40 V and 0.5 mm, respectively. Conclusions With an appropriate flow rate and surgical time, ADPJ successfully induced massage of the retinal vessels and intravenous DBC while maintaining safe IOP and not causing retinal complications. Translational Relevance The ADPJ system has promise as a safe and minimally invasive instrument for the intraocular surgical treatment of human retinal vascular diseases. PMID:25674359

  17. Epidemiology of hemorrhagic fever viruses.

    PubMed

    LeDuc, J W

    1989-01-01

    Twelve distinct viruses associated with hemorrhagic fever in humans are classified among four families: Arenaviridae, which includes Lassa, Junin, and Machupo viruses; Bunyaviridae, which includes Rift Valley fever, Crimean-Congo hemorrhagic fever, and Hantaan viruses; Filoviridae, which includes Marburg and Ebola viruses; and Flaviviridae, which includes yellow fever, dengue, Kyasanur Forest disease, and Omsk viruses. Most hemorrhagic fever viruses are zoonoses, with the possible exception of the four dengue viruses, which may continually circulate among humans. Hemorrhagic fever viruses are found in both temperate and tropical habitats and generally infect both sexes and all ages, although the age and sex of those infected are frequently influenced by the possibility of occupational exposure. Transmission to humans is frequently by bite of an infected tick or mosquito or via aerosol from infected rodent hosts. Aerosol and nosocomial transmission are especially important with Lassa, Junin, Machupo, Crimean-Congo hemorrhagic fever, Marburg, and Ebola viruses. Seasonality of hemorrhagic fever among humans is influenced for the most part by the dynamics of infected arthropod or vertebrate hosts. Mammals, especially rodents, appear to be important natural hosts for many hemorrhagic fever viruses. The transmission cycle for each hemorrhagic fever virus is distinct and is dependent upon the characteristics of the primary vector species and the possibility for its contact with humans.

  18. The Retinal Homeobox (Rx) gene is necessary for retinal regeneration

    PubMed Central

    Martinez-De Luna, Reyna I.; Kelly, Lisa E.; El-Hodiri, Heithem M.

    2011-01-01

    The Retinal Homeobox (Rx) gene is essential for vertebrate eye development. Rx function is required for the specification and maintenance of retinal progenitor cells (RPCs). Loss of Rx function leads to a lack of eye development in a variety of species. Here we show that Rx function is also necessary during retinal regeneration. We performed a thorough characterization of retinal regeneration after partial retinal resection in pre-metamorphic X. laevis. We show that after injury the wound is repopulated with retinal progenitor cells (RPCs) that express Rx and other RPC marker genes. We used an shRNA-based approach to specifically silence Rx expression in vivo in tadpoles. We found that loss of Rx function results in impaired retinal regeneration, including defects in the cells that repopulate the wound and the RPE at the wound site. We show that the regeneration defects can be rescued by provision of exogenous Rx. These results demonstrate for the first time that Rx, in addition to being essential during retinal development, also functions during retinal regeneration. PMID:21334323

  19. Retinal Detachment: Torn or Detached Retina Diagnosis

    MedlinePlus

    ... Eye Health / Eye Health A-Z Detached or Torn Retina Sections Retinal Detachment: What Is a Torn ... Retina Treatment Retinal Detachment Vision Simulator Retinal Detachment: Torn or Detached Retina Diagnosis Written by: Kierstan Boyd ...

  20. Retinal Detachment: Torn or Detached Retina Symptoms

    MedlinePlus

    ... Eye Health / Eye Health A-Z Detached or Torn Retina Sections Retinal Detachment: What Is a Torn ... Retina Treatment Retinal Detachment Vision Simulator Retinal Detachment: Torn or Detached Retina Symptoms Written by: Kierstan Boyd ...

  1. Small Animal Retinal Imaging

    NASA Astrophysics Data System (ADS)

    Choi, WooJhon; Drexler, Wolfgang; Fujimoto, James G.

    Developing and validating new techniques and methods for small animal imaging is an important research area because there are many small animal models of retinal diseases such as diabetic retinopathy, age-related macular degeneration, and glaucoma [1-6]. Because the retina is a multilayered structure with distinct abnormalities occurring in different intraretinal layers at different stages of disease progression, there is a need for imaging techniques that enable visualization of these layers individually at different time points. Although postmortem histology and ultrastructural analysis can be performed for investigating microscopic changes in the retina in small animal models, this requires sacrificing animals, which makes repeated assessment of the same animal at different time points impossible and increases the number of animals required. Furthermore, some retinal processes such as neurovascular coupling cannot be fully characterized postmortem.

  2. The peripheral retinal 'map'.

    PubMed Central

    Williams, D. H.

    1975-01-01

    The condition of the periphery of the retinal field of the human eye is of considerable significance, it is suggested, to those participating in various sporting activities. Its boundaries shrink and expand depending upon the physiological conditions imposed both upon the eye and upon the organism as a whole. Consequently its message to the brain may be impaired under stress with resulting danger owing to delayed response. Images Fig. 3 Fig. 4 Fig. 5 PMID:1148574

  3. Inherited Retinal Degenerative Disease Registry

    ClinicalTrials.gov

    2016-03-21

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

  4. Histological aspects of retinal damage following exposure to pulsed Nd:YAG laser radiation in rabbits: indication for mechanism

    NASA Astrophysics Data System (ADS)

    Kadar, T.; Peri, D.; Turetz, J.; Fishbine, E.; Sahar, R.; Egoz, I.; Sapiens, N.; Brandeis, R.

    2007-02-01

    The severity and characteristics of retinal injury following laser radiation derived from laser and tissue related factors. We have previously shown that retinal damage following Nd:YAG Q-switched laser radiation in rabbits was related to physical parameters, i.e. energy levels and number of pulses. Yet, an extremely large variability in the severity of the damage was found under similar exposure paradigms, even within the same retina. This emphasizes the role of the biological variables in the pathological mechanism of laser-induced retinal damage. The aim of the present study was to further study histological parameters of the injury in relation to retinal site and to elucidate their role in the initiation and characteristics of the damage, following various energy levels (10-50 μJ) and number of pulses (1-4). Pigmented rabbits were exposed to Nd:YAG laser radiation (532nm, pulse duration: 20ns). Exposures were conducted in retina tissue, adjacent to the optic nerve, with a total of 20 exposures per retina. Animals were sacrificed 15 min or 24 hours post exposure, eyes enucleated and processed for paraffin embedding. 4μm thick serial sections, stained with hematoxylin and eosin, were examined under light microscopy. Two major types of retinal damage were observed: focal edema confined to the pigmented epithelium and the photoreceptor cells, and hemorrhages, associated with destruction of retinal tissue. While focal edema associated with slight elevation of the photoreceptor layer seems to depend on the pigmented epithelium, hemorrhages were related also to the choroid vasculature at the site of radiation. It is suggested that a thermo-mechanical mechanism is involved in laser induced retinal hemorrhages at energies above 10-30μJ (2-1 pulses, respectively).

  5. Glutamatergic Retinal Waves

    PubMed Central

    Kerschensteiner, Daniel

    2016-01-01

    Spontaneous activity patterns propagate through many parts of the developing nervous system and shape the wiring of emerging circuits. Prior to vision, waves of activity originating in the retina propagate through the lateral geniculate nucleus (LGN) of the thalamus to primary visual cortex (V1). Retinal waves have been shown to instruct the wiring of ganglion cell axons in LGN and of thalamocortical axons in V1 via correlation-based plasticity rules. Across species, retinal waves mature in three stereotypic stages (I–III), in which distinct circuit mechanisms give rise to unique activity patterns that serve specific functions in visual system refinement. Here, I review insights into the patterns, mechanisms, and functions of stage III retinal waves, which rely on glutamatergic signaling. As glutamatergic waves spread across the retina, neighboring ganglion cells with opposite light responses (ON vs. OFF) are activated sequentially. Recent studies identified lateral excitatory networks in the inner retina that generate and propagate glutamatergic waves, and vertical inhibitory networks that desynchronize the activity of ON and OFF cells in the wavefront. Stage III wave activity patterns may help segregate axons of ON and OFF ganglion cells in the LGN, and could contribute to the emergence of orientation selectivity in V1. PMID:27242446

  6. Mitochondrial dysfunction in retinal diseases.

    PubMed

    Barot, Megha; Gokulgandhi, Mitan R; Mitra, Ashim K

    2011-12-01

    The mitochondrion is a vital intracellular organelle for retinal cell function and survival. There is growing confirmation to support an association between mitochondrial dysfunction and a number of retinal degenerations. Investigations have also unveiled mitochondrial genomic instability as one of the contributing factors for age-related retinal pathophysiology. This review highlights the role of mitochondrial dysfunction originating from oxidative stress in the etiology of retinal diseases including diabetic retinopathy, glaucoma and age-related macular degeneration (AMD). Moreover, mitochondrial DNA (mtDNA) damage associated with AMD due to susceptibility of mtDNA to oxidative damage and failure of mtDNA repair pathways is also highlighted in this review. The susceptibility of neural retina and retinal pigment epithelium (RPE) mitochondria to oxidative damage with ageing appears to be a major factor in retinal degeneration. It thus appears that the mitochondrion is a weak link in the antioxidant defenses of retinal cells. In addition, failure of mtDNA repair pathways can also specifically contribute towards pathogenesis of AMD. This review will further summarize the prospective role of mitochondria targeting therapeutic agents for the treatment of retinal disease. Mitochondria based drug targeting to diminish oxidative stress or promote repair of mtDNA damage may offer potential alternatives for the treatment of various retinal degenerative diseases.

  7. Neuroinflammation after intracerebral hemorrhage

    PubMed Central

    Mracsko, Eva; Veltkamp, Roland

    2014-01-01

    Spontaneous intracerebral hemorrhage (ICH) is a particularly severe type of stroke for which no specific treatment has been established yet. Although preclinical models of ICH have substantial methodological limitations, important insight into the pathophysiology has been gained. Mounting evidence suggests an important contribution of inflammatory mechanisms to brain damage and potential repair. Neuroinflammation evoked by intracerebral blood involves the activation of resident microglia, the infiltration of systemic immune cells and the production of cytokines, chemokines, extracellular proteases and reactive oxygen species (ROS). Previous studies focused on innate immunity including microglia, monocytes and granulocytes. More recently, the role of adaptive immune cells has received increasing attention. Little is currently known about the interactions among different immune cell populations in the setting of ICH. Nevertheless, immunomodulatory strategies are already being explored in ICH. To improve the chances of translation from preclinical models to patients, a better characterization of the neuroinflammation in patients is desirable. PMID:25477782

  8. [Application of retinal oximeter in ophthalmology].

    PubMed

    Li, Jing; Ma, Jianmin; Wang, Ningli

    2015-11-01

    Retinal oximeter is a new machine which has been used in the diagnose, treatment and research of several ophthalmic diseases for recent years. It allows ophthalmologists to gain retinal oxygen saturation directly. Therefore, retinal oximeter might be useful for ophthalmologists to understand ophthalmic diseases more deeper and clarify the impact of ischemia on retinal function. It has been reported in the literatures that retinal oximeter has potentially useful diagnostic and therapeutic indications in various eye diseases such as diabetic retinopathy, central retinal vein and artery occlusion, retinitis pigmentosa, glaucomatous optic neuropathy, et al. In this thesis, the application of retinal oximeter in ophthalmology is reviewed.

  9. Fundus autofluorescence and optical coherence tomography in the management of progressive outer retinal necrosis

    PubMed Central

    Yeh, Steven; Wong, Wai T.; Weichel, Eric D.; Lew, Julie C.; Chew, Emily Y.; Nussenblatt, Robert B.

    2011-01-01

    A 41 year-old female patient with acquired immune deficiency syndrome (AIDS) presented with progressive nasal visual field loss in her right eye. Ophthalmic exam revealed widespread areas of retinal opacification with hemorrhage consistent with progressive outer retinal necrosis (PORN), which was confirmed by polymerase chain reaction (PCR) for varicella zoster virus (VZV) DNA. The patient was treated with intravenous and intravitreal foscarnet and ganciclovir with a resultant improvement clinically. Optical coherence tomography (OCT) and fundus autofluorescence (FAF) imaging revealed progressive changes indicative of widespread retinal pigment epithelial (RPE) and outer retinal dysfunction. OCT was useful in documenting progressive changes in macular architecture during therapy including neurosensory elevation, cystoid macular edema, and severe outer retinal necrosis, at initial exam, 1 week, and 1 month follow-up. Fundus autofluorescence revealed areas of stippled, hyperfluorescence within extensive zones of hypofluorescence, which progressed during the follow-up period. These areas appeared to represent lipofuscin or its photoreactive components within larger regions of RPE loss. The combination of OCT and FAF was useful in the characterization of the RPE and retinal anatomy in this patient with PORN. PMID:20337261

  10. Intraocular retinal prosthesis.

    PubMed Central

    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 generate millions of pixels/light points to create useful vision. METHODS: For electrophysiologic experiments, 2 different setups were used. In the first setup, charge-balanced pulses were delivered to the retinal surface via electrodes inserted through an open sky approach in normal or blind retinal degenerate (rd) mice. In the second setup, the rabbit retina was removed under red light conditions from an enucleated eye and then maintained in a chamber while being superfused with oxygenated, heated Ames media. In both setups, stimulating electrodes and recording electrodes were positioned on the retinal surface to evaluate the effect of varying stimulation parameters on the orthodromic retinal responses (i.e., recording electrode placed between stimulating electrodes and optic nerve head). For psychophysical experiments, visual images were divided into pixels of light that could be projected in a pattern on the retina in up to 8 sighted volunteers. Subjects were asked to perform various tasks ranging from reading and face recognition to various activities of daily living. RESULTS: Electrophysiologic experiments: In a normal mouse, a single cycle of a 1-kHz sine wave was significantly more efficient than a 1-kHz square wave (P < .05), but no such difference was noted in either of the 8- or 16-week-old rd mouse groups (8-week-old, P = .426; 16-week-old, P = .078). Charge threshold was significantly higher in 16-week-old rd mouse versus both 8-week-old rd and normal mouse for every

  11. Inner retinal damage after exposure to green diode laser during a laser show

    PubMed Central

    Jeon, Sohee; Lee, Won Ki

    2014-01-01

    Here we report two cases of retinal damage after exposure to a 510 nm laser diode during a laser show. The first patient was a 20-year-old female who presented with decreased visual acuity in her right eye after visiting a dance party with a diode laser show (wavelength 510 nm, power 2 mW), although she did not directly see the light. Retinal examination revealed a sub-internal limiting membrane hemorrhage and a small laser burn. The second patient was a 20-year-old female who visited for decreased vision in her left eye. She described similar events as the first patient. An exposure to green diode laser can result in retinal damage. It is strongly recommended that certified personnel operate laser devices used in indoor laser shows under strict regulation. PMID:25506208

  12. Retinal Imaging and Image Analysis

    PubMed Central

    Abràmoff, Michael D.; Garvin, Mona K.; Sonka, Milan

    2011-01-01

    Many important eye diseases as well as systemic diseases manifest themselves in the retina. While a number of other anatomical structures contribute to the process of vision, this review focuses on retinal imaging and image analysis. Following a brief overview of the most prevalent causes of blindness in the industrialized world that includes age-related macular degeneration, diabetic retinopathy, and glaucoma, the review is devoted to retinal imaging and image analysis methods and their clinical implications. Methods for 2-D fundus imaging and techniques for 3-D optical coherence tomography (OCT) imaging are reviewed. Special attention is given to quantitative techniques for analysis of fundus photographs with a focus on clinically relevant assessment of retinal vasculature, identification of retinal lesions, assessment of optic nerve head (ONH) shape, building retinal atlases, and to automated methods for population screening for retinal diseases. A separate section is devoted to 3-D analysis of OCT images, describing methods for segmentation and analysis of retinal layers, retinal vasculature, and 2-D/3-D detection of symptomatic exudate-associated derangements, as well as to OCT-based analysis of ONH morphology and shape. Throughout the paper, aspects of image acquisition, image analysis, and clinical relevance are treated together considering their mutually interlinked relationships. PMID:21743764

  13. Perceptual Fading without Retinal Adaptation

    ERIC Educational Resources Information Center

    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…

  14. High resolution optoelectronic retinal prosthesis

    NASA Astrophysics Data System (ADS)

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

    2009-02-01

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

  15. Hemorrhagic complications in dermatologic surgery

    PubMed Central

    Bunick, Christopher G.; Aasi, Sumaira Z.

    2014-01-01

    The ability to recognize, manage, and, most importantly, prevent hemorrhagic complications is critical to performing dermatologic procedures that have safe and high quality outcomes. This article reviews the preoperative, intraoperative, and postoperative factors and patient dynamics that are central to preventing such an adverse outcome. Specifically, the role that anticoagulants and antiplatelet agents, hypertension, and other medical conditions play in the development of postoperative hemorrhage are discussed. In addition, this article provides practical guidelines on managing bleeding during and after surgery. PMID:22515669

  16. Retinal connectivity and primate vision

    PubMed Central

    Lee, Barry B.; Martin, Paul R.; Grünert, Ulrike

    2012-01-01

    The general principles of retinal organization are now well known. It may seem surprising that retinal organization in the primate, which has a complex visual behavioral repertoire, appears relatively simple. In this review, we primarily consider retinal structure and function in primate species. Photoreceptor distribution and connectivity are considered as are connectivity in the outer and inner retina. One key issue is the specificity of retinal connections; we suggest that the retina shows connectional specificity but this is seldom complete, and we consider here the functional consequences of imprecise wiring. Finally, we consider how retinal systems can be linked to psychophysical descriptions of different channels, chromatic and luminance, which are proposed to exist in the primate visual system. PMID:20826226

  17. Dengue and dengue hemorrhagic fever.

    PubMed

    Gubler, D J

    1998-07-01

    Dengue fever, a very old disease, has reemerged in the past 20 years with an expanded geographic distribution of both the viruses and the mosquito vectors, increased epidemic activity, the development of hyperendemicity (the cocirculation of multiple serotypes), and the emergence of dengue hemorrhagic fever in new geographic regions. In 1998 this mosquito-borne disease is the most important tropical infectious disease after malaria, with an estimated 100 million cases of dengue fever, 500,000 cases of dengue hemorrhagic fever, and 25,000 deaths annually. The reasons for this resurgence and emergence of dengue hemorrhagic fever in the waning years of the 20th century are complex and not fully understood, but demographic, societal, and public health infrastructure changes in the past 30 years have contributed greatly. This paper reviews the changing epidemiology of dengue and dengue hemorrhagic fever by geographic region, the natural history and transmission cycles, clinical diagnosis of both dengue fever and dengue hemorrhagic fever, serologic and virologic laboratory diagnoses, pathogenesis, surveillance, prevention, and control. A major challenge for public health officials in all tropical areas of the world is to develop and implement sustainable prevention and control programs that will reverse the trend of emergent dengue hemorrhagic fever.

  18. Long-Term Follow-Up Case of Multiple Retinal Arterial Macroaneurysms Developing Branch Retinal Vein Occlusion following Ruptured Macroaneurysm

    PubMed Central

    Terubayashi, Yuya; Kida, Teruyo; Fukumoto, Masanori; Sugasawa, Jun; Morishita, Seita; Suzuki, Hiroyuki; Ikeda, Tsunehiko

    2016-01-01

    Purpose Retinal arterial macroaneurysm (RAM) has been reported in association with branch retinal vein occlusion (BRVO), and usually BRVO precedes RAM. We present a long-term follow-up case report of unilateral multiple RAMs that developed BRVO following ruptured RAM in the same retinal quadrant. Case Presentation An 80-year-old woman presented with floaters in her right eye in June 2012. Visual acuity (VA) was 20/25 in her right eye with posterior capsular opacity. Her fundus showed the first ruptured RAM at the superotemporal vascular arcade with subinternal limiting membrane and subretinal hemorrhages not involving the macula. These were absorbed gradually with a VA of 20/20. After 2 years, the second RAM at the proximal superotemporal vascular arcade developed and impending BRVO occurred with macular edema at the distal site of the RAM. With the RAM located close to the arteriovenous crossing, her VA was dropped to 20/60. Intravitreal injection of ranibizumab was performed and macular edema was resolved with improved vision of 20/30. Three months later, she realized a sudden vision loss of 2/200. Her posterior pole showed massive pre- and subretinal hemorrhages, and vitrectomy was performed. The source of bleeding was the third RAM's rupture in a different artery. Her vision improved to 20/30. The unaffected eye showed no RAMs. Conclusion We experienced a long-term follow-up case of multiple RAMs showing different courses. We should cautiously note that BRVO can occur following RAM at the arteriovenous crossing. PMID:27462250

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

    PubMed Central

    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.

  20. Diffuse Alveolar Hemorrhage

    PubMed Central

    2013-01-01

    Diffuse alveolar hemorrhage (DAH) is a life-threatening and medical emergency that can be caused by numerous disorders and presents with hemoptysis, anemia, and diffuse alveolar infiltrates. Early bronchoscopy with bronchoalveolar lavage is usually required to confirm the diagnosis and rule out infection. Most cases of DAH are caused by capillaritis associated with systemic autoimmune diseases such as anti-neutrophil cytoplasmic antibody-associated vasculitis, anti-glomerular basement membrane disease, and systemic lupus erythematosus, but DAH may also result from coagulation disorders, drugs, inhaled toxins, or transplantation. The diagnosis of DAH relies on clinical suspicion combined with laboratory, radiologic, and pathologic findings. Early recognition is crucial, because prompt diagnosis and treatment is necessary for survival. Corticosteroids and immunosuppressive agents remain the gold standard. In patients with DAH, biopsy of involved sites can help to identify the cause and to direct therapy. This article aims to provide a general review of the causes and clinical presentation of DAH and to recommend a diagnostic approach and a management plan for the most common causes. PMID:23678356

  1. Diffuse alveolar hemorrhage.

    PubMed

    Park, Moo Suk

    2013-04-01

    Diffuse alveolar hemorrhage (DAH) is a life-threatening and medical emergency that can be caused by numerous disorders and presents with hemoptysis, anemia, and diffuse alveolar infiltrates. Early bronchoscopy with bronchoalveolar lavage is usually required to confirm the diagnosis and rule out infection. Most cases of DAH are caused by capillaritis associated with systemic autoimmune diseases such as anti-neutrophil cytoplasmic antibody-associated vasculitis, anti-glomerular basement membrane disease, and systemic lupus erythematosus, but DAH may also result from coagulation disorders, drugs, inhaled toxins, or transplantation. The diagnosis of DAH relies on clinical suspicion combined with laboratory, radiologic, and pathologic findings. Early recognition is crucial, because prompt diagnosis and treatment is necessary for survival. Corticosteroids and immunosuppressive agents remain the gold standard. In patients with DAH, biopsy of involved sites can help to identify the cause and to direct therapy. This article aims to provide a general review of the causes and clinical presentation of DAH and to recommend a diagnostic approach and a management plan for the most common causes.

  2. Aneurysmal Subarachnoid Hemorrhage

    PubMed Central

    2015-01-01

    Aneurysmal subarachnoid hemorrhage (SAH) is a worldwide health burden with high fatality and permanent disability rates. The overall prognosis depends on the volume of the initial bleed, rebleeding, and degree of delayed cerebral ischemia (DCI). Cardiac manifestations and neurogenic pulmonary edema indicate the severity of SAH. The International Subarachnoid Aneurysm Trial (ISAT) reported a favorable neurological outcome with the endovascular coiling procedure compared with surgical clipping at the end of 1 year. The ISAT trial recruits were primarily neurologically good grade patients with smaller anterior circulation aneurysms, and therefore the results cannot be reliably extrapolated to larger aneurysms, posterior circulation aneurysms, patients presenting with complex aneurysm morphology, and poor neurological grades. The role of hypothermia is not proven to be neuroprotective according to a large randomized controlled trial, Intraoperative Hypothermia for Aneurysms Surgery Trial (IHAST II), which recruited patients with good neurological grades. Patients in this trial were subjected to slow cooling and inadequate cooling time and were rewarmed rapidly. This methodology would have reduced the beneficial effects of hypothermia. Adenosine is found to be beneficial for transient induced hypotension in 2 retrospective analyses, without increasing the risk for cardiac and neurological morbidity. The neurological benefit of pharmacological neuroprotection and neuromonitoring is not proven in patients undergoing clipping of aneurysms. DCI is an important cause of morbidity and mortality following SAH, and the pathophysiology is likely multifactorial and not yet understood. At present, oral nimodipine has an established role in the management of DCI, along with maintenance of euvolemia and induced hypertension. Following SAH, hypernatremia, although less common than hyponatremia, is a predictor of poor neurological outcome. PMID:25272066

  3. Aneurysmal Subarachnoid Hemorrhage.

    PubMed

    D'Souza, Stanlies

    2015-07-01

    Aneurysmal subarachnoid hemorrhage (SAH) is a worldwide health burden with high fatality and permanent disability rates. The overall prognosis depends on the volume of the initial bleed, rebleeding, and degree of delayed cerebral ischemia (DCI). Cardiac manifestations and neurogenic pulmonary edema indicate the severity of SAH. The International Subarachnoid Aneurysm Trial (ISAT) reported a favorable neurological outcome with the endovascular coiling procedure compared with surgical clipping at the end of 1 year. The ISAT trial recruits were primarily neurologically good grade patients with smaller anterior circulation aneurysms, and therefore the results cannot be reliably extrapolated to larger aneurysms, posterior circulation aneurysms, patients presenting with complex aneurysm morphology, and poor neurological grades. The role of hypothermia is not proven to be neuroprotective according to a large randomized controlled trial, Intraoperative Hypothermia for Aneurysms Surgery Trial (IHAST II), which recruited patients with good neurological grades. Patients in this trial were subjected to slow cooling and inadequate cooling time and were rewarmed rapidly. This methodology would have reduced the beneficial effects of hypothermia. Adenosine is found to be beneficial for transient induced hypotension in 2 retrospective analyses, without increasing the risk for cardiac and neurological morbidity. The neurological benefit of pharmacological neuroprotection and neuromonitoring is not proven in patients undergoing clipping of aneurysms. DCI is an important cause of morbidity and mortality following SAH, and the pathophysiology is likely multifactorial and not yet understood. At present, oral nimodipine has an established role in the management of DCI, along with maintenance of euvolemia and induced hypertension. Following SAH, hypernatremia, although less common than hyponatremia, is a predictor of poor neurological outcome.

  4. Vitreous Mediators in Retinal Hypoxic Diseases

    PubMed Central

    dell'Omo, Roberto; Semeraro, Francesco; Bamonte, Giulio; Cifariello, Francesco; Romano, Mario R.; Costagliola, Ciro

    2013-01-01

    The causes of retinal hypoxia are many and varied. Under hypoxic conditions, a variety of soluble factors are secreted into the vitreous cavity including growth factors, cytokines, and chemokines. Cytokines, which usually serve as signals between neighboring cells, are involved in essentially every important biological process, including cell proliferation, inflammation, immunity, migration, fibrosis, tissue repair, and angiogenesis. Cytokines and chemokines are multifunctional mediators that can direct the recruitment of leukocytes to sites of inflammation, promote the process, enhance immune responses, and promote stem cell survival, development, and homeostasis. The modern particle-based flow cytometric analysis is more direct, stable and sensitive than the colorimetric readout of the conventional ELISA but, similar to ELISA, is influenced by vitreous hemorrhage, disruption of the blood-retina barrier, and high serum levels of a specific protein. Finding patterns in the expression of inflammatory cytokines specific to a particular disease can substantially contribute to the understanding of its basic mechanism and to the development of a targeted therapy. PMID:23365490

  5. Retinal vasculitis and ocular vitreous metastasis following complete response to PD-1 inhibition in a patient with metastatic cutaneous melanoma.

    PubMed

    Manusow, Joshua S; Khoja, Leila; Pesin, Nataly; Joshua, Anthony M; Mandelcorn, Efrem D

    2014-01-01

    We report on a 36-year-old woman treated with the anti PD-1 antibody Pembrolizumab for metastatic cutaneous melanoma in the first line setting. She achieved a complete response and then relapsed with metastases to the vitreous cavity with an associated angiographically determined retinal vasculitis. Vitreous metastasis without choroidal involvement is unusual and may be due to individual cell extravasation, vitreous hemorrhage containing malignant cells, or direct spread through the optic nerve. This finding highlights the need for immune sanctuary sites to be monitored in the presence of PD-1 inhibition and we hypothesize that the use of PD-1 inhibitor potentiated the patient's angiographically determined retinal vasculitis. PMID:25516805

  6. Anti-VEGF Therapy for Retinal Vein Occlusions.

    PubMed

    Campa, Claudio; Alivernini, Giuseppe; Bolletta, Elena; Parodi, Maurizio Battaglia; Perri, Paolo

    2016-01-01

    Retinal vein occlusion (RVO) is the second most common cause of visual loss in the Western World. RVO is usually classified into branch RVO (BRVO) and central RVO (CRVO) according to the anatomical site of the vascular occlusion. The pathogenesis of RVO is not yet fully understood, however an important event is the intraluminal thrombus formation, which is usually secondary to several conditions such as hypertension, hyperlipidemia, diabetes and thrombophilia. The blockage of venous circulation causes an elevation of intraluminal pressure in the capillaries, leading to hemorrhages and leakage of fluid within the retina, increase of interstitial pressure and a consequent reduction of retinal perfusion. Ischemia may develop resulting in secretion of vascular endothelial growth factor (VEGF) that causes further vascular leakage and retinal oedema. VEGF has therefore a leading role in RVO pathogenesis and symptoms. As a consequence use of anti-VEGF agents by intravitreal injections has become very common with the aim to improve the clinical outcomes in these patients. Currently 2 anti-VEGF agents (ranimizumab and aflibercept) have been FDA (Food and Drug Administration) and EMA (European Medicine Agency) approved for the treatment of RVO, while another VEGF inhibitor (bevacizumab) is often used "off-label" in clinical practice. Many treatment regimens have been suggested in the clinical trials with these drugs, as monthly injections or injections when needed, however the ideal regimen has not been defined yet. We conducted a systematic review searching MEDLINE for the following terms: retinal vein occlusion, ranibizumab, bevacizumab, aflibercept, vascular endothelial growth factor, macular oedema. Data were extracted by one author (AG and BE) and checked by a second (BPM, CC). Aim of this article was to review available data for each drug, focusing on their efficacy and safety trying to compare their advantages and limits.

  7. Octreotide, a Somatostatin Analogue, Fails to Inhibit Hypoxia-induced Retinal Neovascularization in the Neonatal Rat

    PubMed Central

    Averbukh, Edward; Halpert, Michael; Yanko, Ravit; Yanko, Lutza; Peèr, Jacob; Levinger, Samuel; Flyvbjerg, Allan

    2000-01-01

    Objective: Octreotide, a somatostatin analogue, has been shown to prevent angiogenesis in diverse in vitro models. We evaluated its effect on retinal neovascularization in vivo, using a neonatal rat retinopathy model. Methods: We used, on alternating days, hypoxia (10% O2) and hyperoxia (50% O2) during the first 14 days of neonatal rats, to induce retinal neovascularization. Half of the rats were injected subcutaneously with octreotide 0.7 μg/g BW twice daily. At day 18 the eyes were evaluated for the presence of epiretinal and vitreal hemorrhage, neovascularization and epiretinal proliferation. Octreotide pharmacokinetics and its effect on serum growth hormone (GH) and insulin-like growth factor I (IGF-I) were examined in 28 rats. Results: Serum octreotide levels were 667 μg/1 two hours after injection, 26.4 μg/1 after nine hours and 3.2 μg/1 after 14 hours. GH levels were decreased by 40% (p = 0.002) two hours after injection but thereafter returned to baseline. IGF-I levels were unchanged two hours after injection and were elevated by 26% 14 hours after injection (p = 0.02). Epiretinal membranes were highly associated with epiretinal hemorrhages (p < 0.001), while retinal neovascularization was notably associated with vitreal hemorrhages (p < 0.001). Conclusions: Twice-daily injections of octreotide failed to produce sustained decrease in serum GH, but produced rebound elevation of serum IGF-I. Accordingly, no statistically significant effect of injections on retinal pathology was noted. This finding, however, does not contradict our assumption that GH suppression may decrease the severity of retinopathy. PMID:11469389

  8. Flexible retinal electrode array

    DOEpatents

    Okandan, Murat; Wessendorf, Kurt O.; Christenson, Todd R.

    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.

  9. Hypoxia-Induced Retinal Neovascularization in Zebrafish Embryos: A Potential Model of Retinopathy of Prematurity

    PubMed Central

    Kao, Alex; Hsi, Brian; Lee, Shwu-Huey; Chen, Yau-Hung; Wang, I-Jong

    2015-01-01

    Retinopathy of prematurity, formerly known as a retrolental fibroplasia, is a leading cause of infantile blindness worldwide. Retinopathy of prematurity is caused by the failure of central retinal vessels to reach the retinal periphery, creating a nonperfused peripheral retina, resulting in retinal hypoxia, neovascularization, vitreous hemorrhage, vitreoretinal fibrosis, and loss of vision. We established a potential retinopathy of prematurity model by using a green fluorescent vascular endothelium zebrafish transgenic line treated with cobalt chloride (a hypoxia-inducing agent), followed by GS4012 (a vascular endothelial growth factor inducer) at 24 hours postfertilization, and observed that the number of vascular branches and sprouts significantly increased in the central retinal vascular trunks 2–4 days after treatment. We created an angiography method by using tetramethylrhodamine dextran, which exhibited severe vascular leakage through the vessel wall into the surrounding retinal tissues. The quantification of mRNA extracted from the heads of the larvae by using real-time quantitative polymerase chain reaction revealed a twofold increase in vegfaa and vegfr2 expression compared with the control group, indicating increased vascular endothelial growth factor signaling in the hypoxic condition. In addition, we demonstrated that the hypoxic insult could be effectively rescued by several antivascular endothelial growth factor agents such as SU5416, bevacizumab, and ranibizumab. In conclusion, we provide a simple, highly reproducible, and clinically relevant retinopathy of prematurity model based on zebrafish embryos; this model may serve as a useful platform for clarifying the mechanisms of human retinopathy of prematurity and its progression. PMID:25978439

  10. Intracerebral hemorrhage and cognitive impairment.

    PubMed

    Xiong, Li; Reijmer, Yael D; Charidimou, Andreas; Cordonnier, Charlotte; Viswanathan, Anand

    2016-05-01

    Vascular cognitive impairment and vascular dementia are composed of cognitive deficits resulted from a range of vascular lesions and pathologies, including both ischemic and hemorrhagic. However the contribution of spontaneous intracerebral hemorrhage presumed due to small vessel diseases on cognitive impairment is underestimated, in contrast to the numerous studies about the role of ischemic vascular disorders on cognition. In this review we summarize recent findings from clinical studies and appropriate basic science research to better elucidate the role and possible mechanisms of intracerebral hemorrhage in cognitive impairment and dementia. This article is part of a Special Issue entitled: Vascular Contributions to Cognitive Impairment and Dementia edited by M. Paul Murphy, Roderick A. Corriveau and Donna M. Wilcock.

  11. Intraocular retinal transplantation: a review.

    PubMed

    Hammer, R M; Yinon, U

    1991-01-01

    This review covers intraocular transplantation of retinal tissue. This has importance both for theoretical understanding of retinal and neural development and for possible future clinical application. Transplantation sites have ranged from the anterior chamber through the retina to the subretinal space. Transplanted tissue has ranged from whole retina to specific retinal layers or specific types of retinal cells. Both within-species and inter-species transplants have been performed, and donor age has ranged from embryonic to adult. The ability of transplanted tissue to be accepted and to differentiate in host eyes has been studied. The conditions under which successful transplants are obtained, host-graft interactions, and transplantation methodologies have been explored. Morphological, and to a small extent, also functional characteristics of the transplants have been studied. PMID:1747393

  12. ROLLER COASTER RETINOPATHY: CASE REPORT OF SYMPTOMATIC BILATERAL INTRARETINAL HEMORRHAGES AFTER SHAKING INJURY IN AN OTHERWISE HEALTHY ADULT

    PubMed Central

    Patel, Yogin P.; Saraf, Steven S.; Desai, Uday R.

    2016-01-01

    Purpose: Traumatic head injuries not involving the eye have been known to cause retinal injury through multiple mechanisms. Abusive head trauma remains the prototypical example. We propose to demonstrate the first case of bilateral multiple retinal hemorrhages in a young healthy adult related to riding multiple theme park roller coasters. Methods: The patient was evaluated with a complete ophthalmic examination including dilated extended ophthalmoscopy, fluorescein angiography, optical coherence tomography, and fundus photography. Results: The patient was found to have a bilateral symptomatic macular retinopathy characterized by multiple intraretinal hemorrhages. Given the lack of other systemic findings and negative medical workup, her signs and symptoms were thought to be attributed to the same day attendance of a theme park and riding of multiple roller coasters. Conclusion: Theme park roller coasters, as well as other attractions, may affect the eye at the vitreoretinal interface. This type of acceleration–deceleration injury should be considered in the differential of an adolescent or adult patient with retinal hemorrhage in the absence of other pathologic processes to explain clinical findings. PMID:26630245

  13. Microsystems Technology for Retinal Implants

    NASA Astrophysics Data System (ADS)

    Weiland, James

    2005-03-01

    The retinal prosthesis is targeted to treat age-related macular degeneration, retinitis pigmentosa, and other outer retinal degenerations. Simulations of artificial vision have predicted that 600-1000 individual pixels will be needed if a retinal prosthesis is to restore function such as reading large print and face recognition. An implantable device with this many electrode contacts will require microsystems technology as part of its design. An implantable retinal prosthesis will consist of several subsystems including an electrode array and hermetic packaging. Microsystems and microtechnology approaches are being investigated as possible solutions for these design problems. Flexible polydimethylsiloxane (PDMS) substrate electrode arrays and silicon micromachined electrode arrays are under development. Inactive PDMS electrodes have been implanted in 3 dogs to assess mechanical biocompatibility. 3 dogs were followed for 6 months. The implanted was securely fastened to the retina with a single retinal tack. No post-operative complications were evident. The array remained within 100 microns of the retinal surface. Histological evaluation showed a well preserved retina underneath the electrode array. A silicon device with electrodes suspended on micromachined springs has been implanted in 4 dogs (2 acute implants, 2 chronic implants). The device, though large, could be inserted into the eye and positioned on the retina. Histological analysis of the retina from the spring electrode implants showed that spring mounted posts penetrated the retina, thus the device will be redesigned to reduce the strength of the springs. These initial implants will provide information for the designers to make the next generation silicon device. We conclude that microsystems technology has the potential to make possible a retinal prosthesis with 1000 individual contacts in close proximity to the retina.

  14. Crimean-Congo Hemorrhagic Fever (CCHF)

    MedlinePlus

    ... Congo Hemorrhagic Fever (CCHF) [PDF - 2 pages] Virus Ecology Viral Hemorrhagic Fever (VHF) Information for Specific Groups ... Diagnosis Treatment Prevention Outbreak Distribution Map Resources Virus Ecology File Formats Help: How do I view different ...

  15. The mechanics of retinal detachment

    NASA Astrophysics Data System (ADS)

    Chou, Tom; Siegel, Michael

    2013-03-01

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

  16. Retinal oxygen extraction in humans

    NASA Astrophysics Data System (ADS)

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

    2015-10-01

    Adequate function of the retina is dependent on proper oxygen supply. In humans, the inner retina is oxygenated via the retinal circulation. We present a method to calculate total retinal oxygen extraction based on measurement of total retinal blood flow using dual-beam bidirectional Doppler optical coherence tomography and measurement of oxygen saturation by spectrophotometry. These measurements were done on 8 healthy subjects while breathing ambient room air and 100% oxygen. Total retinal blood flow was 44.3 ± 9.0 μl/min during baseline and decreased to 18.7 ± 4.2 μl/min during 100% oxygen breathing (P < 0.001) resulting in a pronounced decrease in retinal oxygen extraction from 2.33 ± 0.51 μl(O2)/min to 0.88 ± 0.14 μl(O2)/min during breathing of 100% oxygen. The method presented in this paper may have significant potential to study oxygen metabolism in hypoxic retinal diseases such as diabetic retinopathy.

  17. Retinal implants: a systematic review.

    PubMed

    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

  18. RETINOPATHY OF PREMATURITY: INVOLUTION, FACTORS PREDISPOSING TO RETINAL DETACHMENT, AND EXPECTED UTILITY OF PREEMPTIVE SURGICAL REINTERVENTION

    PubMed Central

    Coats, David K

    2005-01-01

    Purpose To characterize involution of retinopathy of prematurity (ROP) following treatment at threshold, to identify findings during involution that portend development of retinal detachment, and to assess the potential utility of preemptive vitrectomy for eyes with high-risk features. Methods The probability of ROP involution and of retinal detachment evolution over time was analyzed in 262 treated eyes of 138 infants in a retrospective observational non–case controlled series. Expected utility of preemptive reintervention in eyes with high-risk features was evaluated using decision analysis. Modifications were devised to enhance classification of advanced ROP. Results ROP fully involuted in approximately 80% of eyes within 28 days of treatment. Vitreous organization meeting the study’s clinically important definition was associated with a 31-fold (5.37 to 183.63; P < .0001) and a 13-fold (2.97 to 58.59; P < .0001) increase in the odds for retinal detachment for right and left eyes, respectively. Vitreous hemorrhage defined as clinically important was associated with a 38-fold (2.69 to 551.19; P = .007) and a 15-fold (1.65 to 144.12; P = .02) increase in the odds for retinal detachment for right and left eyes, respectively. As modeled, an expected utility of 0.85 was calculated for preemptive vitrectomy compared with 0.79 for deferred vitrectomy for eyes with clinically important vitreous organization. Conclusions Acute-phase ROP involuted quickly in most eyes. Vitreous organization and vitreous hemorrhage were predictive of eyes that developed a retinal detachment. Decision analysis suggests that preemptive vitrectomy for eyes with vitreous organization meeting specific criteria is not likely to be worse than deferred vitrectomy, and it could be advantageous in some scenarios. PMID:17057808

  19. Ruptured retinal arterial macroaneurysm: diagnosis and management.

    PubMed

    Speilburg, Ashley M; Klemencic, Stephanie A

    2014-01-01

    Retinal arterial macroaneurysm is an acquired, focal dilation of a retinal artery, typically occurring within the first three bifurcations of the central retinal artery. The clinical presentation of a retinal arterial macroaneurysm is highly variable, making initial diagnosis difficult and differentials many. Identification of retinal arterial macroaneurysms is crucial to appropriately co-manage with the primary care physician for hypertension control. Prognosis is generally good and observation is often an adequate treatment. However, in cases of macular threat or involvement, some treatment options are available and referral to a retinal specialist is indicated.

  20. CT demonstration of bilateral adrenal hemorrhage

    SciTech Connect

    Ling, D.; Korobkin, M.; Silverman, P.M.; Dunnick, N.R.

    1983-08-01

    Bilateral adrenal hemorrhage with subsequent adrenal insufficiency is a recognized complication of anticoagulant therapy. Because the clinical manifestations are often nonspecific, the antemortem diagnosis of adrenal hemorrhage has been a difficult clinical problem. Computed tomography (CT) provides detailed images of the adrenal glands that are not possible with conventional imaging methods. The CT findings of bilateral adrenal hemorrhage in an anticoagulated patient are reported.

  1. Assessing preventability for obstetric hemorrhage.

    PubMed

    Della Torre, Micaela; Kilpatrick, Sarah J; Hibbard, Judith U; Simonson, Louise; Scott, Shirley; Koch, Abby; Schy, Deborah; Geller, Stacie E

    2011-12-01

    We sought to determine preventability for cases of obstetric hemorrhage, identify preventable factors, and compare differences between levels of hospital. We retrospectively reviewed a 1-year cohort of severe and near-miss obstetric hemorrhage in an urban perinatal network. An expert panel, using a validated preventability model, reviewed all cases. Preventability and distribution of preventability factors were compared between levels of hospital care. Sixty-three severe and near-miss obstetric hemorrhage cases were identified from 11 hospitals; 54% were deemed potentially preventable. Overall preventability was not statistically different by level of hospital, and 88% were provider related. The only treatment-related preventability factors were significantly different between levels of hospital and significantly less common in level III hospitals (p < 0.01). The majority of obstetric hemorrhage was preventable. The most common potentially preventable factor was provider treatment error, and this was significantly more common in level II hospitals. New interventions should be focused on decreasing providers' treatment errors.

  2. Vital bleach of hemorrhagic discoloration.

    PubMed

    Wong, M; Schmidt, J C

    1991-05-01

    An unusual case is presented of a maxillary central incisor with hemorrhagic discoloration that was successfully treated with the thermocatalytic vital bleach technique. This case emphasizes the need for a thorough radiographic and clinical examination to include vitality tests when a patient presents with a discolored tooth.

  3. Assessing preventability for obstetric hemorrhage.

    PubMed

    Della Torre, Micaela; Kilpatrick, Sarah J; Hibbard, Judith U; Simonson, Louise; Scott, Shirley; Koch, Abby; Schy, Deborah; Geller, Stacie E

    2011-12-01

    We sought to determine preventability for cases of obstetric hemorrhage, identify preventable factors, and compare differences between levels of hospital. We retrospectively reviewed a 1-year cohort of severe and near-miss obstetric hemorrhage in an urban perinatal network. An expert panel, using a validated preventability model, reviewed all cases. Preventability and distribution of preventability factors were compared between levels of hospital care. Sixty-three severe and near-miss obstetric hemorrhage cases were identified from 11 hospitals; 54% were deemed potentially preventable. Overall preventability was not statistically different by level of hospital, and 88% were provider related. The only treatment-related preventability factors were significantly different between levels of hospital and significantly less common in level III hospitals (p < 0.01). The majority of obstetric hemorrhage was preventable. The most common potentially preventable factor was provider treatment error, and this was significantly more common in level II hospitals. New interventions should be focused on decreasing providers' treatment errors. PMID:21698554

  4. Hemorrhagic onset of spinal angiolipoma.

    PubMed

    da Costa, Marcos Devanir Silva; Paz, Daniel de Araujo; Rodrigues, Thiago Pereira; Gandolfi, Ana Camila de Castro; Lamis, Fabricio Correa; Stavale, João Norberto; Suriano, Italo Capraro; Cetl, Luiz Daniel Marques Neves; Cavalheiro, Sergio

    2014-12-01

    Spinal angiolipomas are rare benign tumors that generally induce slow progressive cord compression. Here, the authors describe a case of sudden-onset palsy of the lower extremities caused by hemorrhagic spinal angiolipoma. An emergent laminectomy was performed to achieve total lesion removal. Follow-up examinations indicated neurological improvement and the absence of recurrence.

  5. Mosquito-borne hemorrhagic fevers.

    PubMed

    Lupi, Omar

    2011-01-01

    Arboviruses continue to be a significant source of disease, especially in regions where their insect hosts are endemic. This article highlights these diseases, with particular focus on dengue, yellow fever, and viral hemorrhagic fever. A general background is provided, as well information concerning diagnosis and treatment.

  6. Hemorrhagic complications of severe pancreatitis.

    PubMed

    Stroud, W H; Cullom, J W; Anderson, M C

    1981-10-01

    Massive hemorrhage associated with pancreatitis is a rare but frequently lethal complication. Fifteen patients with this complication are presented. Bleeding occurred in four patients with necrotizing pancreatitis, in three patients with pancreatic abscesses, in seven patients with pseudocysts, and in one patient with chronic relapsing pancreatitis following longitudinal pancreaticojejunostomy. The initial presentation of hemorrhage was gastrointestinal in eight patients and retroperitoneal or intraperitoneal in seven. Abdominal pain with associated nausea and vomiting was present in all patients on admission. Duration of symptoms prior to hospitalization averaged 6 days. During hospitalization the 15 patients received a total of 512 units of blood for transfusions ranging from 8 to 177 units. Admission amylase values were of no benefit in assessing severity of the disease, but application of Ranson's criteria accurately predicted both severity and prognosis. The common denominator in all cases of bleeding appeared to be the presence of an overwhelming or continuing inflammatory process with necrosis and erosion of adjacent vascular and visceral structures. The overall mortality rate in the series was 53.3%. Those patients with hemorrhage associated with pseudocyst formation had the highest survival rates, whereas those with necrotizing pancreatitis and hemorrhage had an extremely poor response to aggressive medical and/or surgical management.

  7. Electrocardiograph abnormalities in intracerebral hemorrhage.

    PubMed

    Takeuchi, Satoru; Nagatani, Kimihiro; Otani, Naoki; Wada, Kojiro; Mori, Kentaro

    2015-12-01

    This study investigated the prevalence and type of electrocardiography (ECG) abnormalities, and their possible association with the clinical/radiological findings in 118 consecutive patients with non-traumatic, non-neoplastic intracerebral hemorrhage (ICH). ECG frequently demonstrates abnormalities in patients with ischemic stroke and subarachnoid hemorrhage, but little is known of ECG changes in ICH patients. Clinical and radiological information was retrospectively reviewed. ECG recordings that were obtained within 24 hours of the initial hemorrhage were analyzed. Sixty-six patients (56%) had one or more ECG abnormalities. The most frequent was ST depression (24%), followed by left ventricular hypertrophy (20%), corrected QT interval (QTc) prolongation (19%), and T wave inversion (19%). The logistic regression analysis demonstrated the following: insular involvement was an independent predictive factor of ST depression (p<0.001; odds ratio OR 10.18; 95% confidence interval [CI] 2.84-36.57); insular involvement (p<0.001; OR 23.98; 95% CI 4.91-117.11) and presence of intraventricular hemorrhage (p<0.001; OR 8.72; 95% CI 2.69-28.29) were independent predictive factors of QTc prolongation; deep hematoma location (p<0.001; OR 19.12; 95% CI 3.82-95.81) and hematoma volume >30 ml (p=0.001; OR 6.58; 95% CI 2.11-20.46) were independent predictive factors of T wave inversion. We demonstrate associations between ECG abnormalities and detailed characteristics of ICH.

  8. [Retinal and corneal dysplasias in the Yorkshire terrier and other dog breeds in Austria].

    PubMed

    Walde, I

    1997-01-01

    Mother and son of a Yorkshire Terrier family showed excessive multifocal retinal dysplasia (RD1) and geographical retinal dysplasia (RD2), intra- and preretinal hemorrhages partial and total retinal detachment (total RD/RD3), residues of the pupillary membrane and as a newness in this combination a geographical, subepithelial corneal opacity, composed of small dots. One, not examined son of the same litter was congenitally blind. Similar corneal opacities were also found in two Rough Collies affected with CEA, RD, and microphthalmia, a young German Wirehair Pointer with primary absolute glaucoma in conjunction with goniodysplasia and RD in the healthy seeming fellow eye as well as in a poodle puppy affected with bilateral posterior suture-line cataract in connection with persistent primary hyperplastic vitreous (PHPV) in one and a globe-shaped deformed retina in connection with a persistent, blood conducting hyaloid artery in the other eye. The latter finally resulted in intraocular hemorrhage and secondary glaucoma. A pathogenetic connection between ocular malformations and subepithelial corneal opacity seems to be likely.

  9. Temperature controlled retinal photocoagulation

    NASA Astrophysics Data System (ADS)

    Schlott, Kerstin; Koinzer, Stefan; Baade, Alexander; Birngruber, Reginald; Roider, Johann; Brinkmann, Ralf

    2013-06-01

    Retinal photocoagulation lacks objective dosage in clinical use, thus the commonly applied lesions are too deep and strong, associated with pain reception and the risk of visual field defects and induction of choroidal neovascularisations. Optoacoustics allows real-time non-invasive temperature measurement in the fundus during photocoagulation by applying short probe laser pulses additionally to the treatment radiation, which excite the emission of ultrasonic waves. Due to the temperature dependence of the Grüneisen parameter, the amplitudes of the ultrasonic waves can be used to derive the temperature of the absorbing tissue. By measuring the temperatures in real-time and automatically controlling the irradiation by feedback to the treatment laser, the strength of the lesions can be defined. Different characteristic functions for the time and temperature dependent lesion sizes were used as rating curves for the treatment laser, stopping the irradiation automatically after a desired lesion size is achieved. The automatically produced lesion sizes are widely independent of the adjusted treatment laser power and individual absorption. This study was performed on anaesthetized rabbits and is a step towards a clinical trial with automatically controlled photocoagulation.

  10. Bilateral macular hemorrhage due to megaloblastic anemia: A rare case report.

    PubMed

    Vaggu, Sree Kumar; Bhogadi, Preethi

    2016-02-01

    We report a case of a 17-year-old female patient who presented with sudden, painless, nonprogressive diminished vision in both eyes (best corrected visual acuity in right eye - 6/60 and left eye - 6/36). An ophthalmological evaluation revealed bilateral pale tarsal conjunctiva and bilateral macular hemorrhage. Hematological evaluation revealed the presence of megalocytic anemia (with hemoglobin - 4.9 g%). General examination showed severe pallor. On systemic examination, no abnormality was detected, confirmed by ultrasonography abdomen. Other causes of severe anemia have been ruled out. Intraocular pressure in both eyes was 12 mmHg. This case documents the rare occurrence of bilateral subinternal limiting membrane macular hemorrhage with megaloblastic anemia without thrombocytopenia and other retinal features of anemic retinopathy. PMID:27050355

  11. Color Doppler imaging of retinal diseases.

    PubMed

    Dimitrova, Galina; Kato, Satoshi

    2010-01-01

    Color Doppler imaging (CDI) is a widely used method for evaluating ocular circulation that has been used in a number of studies on retinal diseases. CDI assesses blood velocity parameters by using ultrasound waves. In ophthalmology, these assessments are mainly performed on the retrobulbar blood vessels: the ophthalmic, the central retinal, and the short posterior ciliary arteries. In this review, we discuss CDI use for the assessment of retinal diseases classified into the following: vascular diseases, degenerations, dystrophies, and detachment. The retinal vascular diseases that have been investigated by CDI include diabetic retinopathy, retinal vein occlusions, retinal artery occlusions, ocular ischemic conditions, and retinopathy of prematurity. Degenerations and dystrophies included in this review are age-related macular degeneration, myopia, and retinitis pigmentosa. CDI has been used for the differential diagnosis of retinal detachment, as well as the evaluation of retrobulbar circulation in this condition. CDI is valuable for research and is a potentially useful diagnostic tool in the clinical setting.

  12. Transcorneal Electrical Stimulation Therapy for Retinal Disease

    ClinicalTrials.gov

    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

  13. A novel platform for minimally invasive delivery of cellular therapy as a thin layer across the subretina for treatment of retinal degeneration

    NASA Astrophysics Data System (ADS)

    Rotenstreich, Ygal; Tzameret, Adi; Kalish, Sapir E.; Belkin, Michael; Meir, Amilia; Treves, Avraham J.; Nagler, Arnon; Sher, Ifat

    2015-03-01

    Incurable retinal degenerations affect millions worldwide. Stem cell transplantation rescued visual functions in animal models of retinal degeneration. In those studies cells were transplanted in subretinal "blebs", limited number of cells could be injected and photoreceptor rescue was restricted to areas in proximity to the injection sites. We developed a minimally-invasive surgical platform for drug and cell delivery in a thin layer across the subretina and extravascular spaces of the choroid. The novel system is comprised of a syringe with a blunt-tipped needle and an adjustable separator. Human bone marrow mesenchymal stem cells (hBM-MSCs) were transplanted in eyes of RCS rats and NZW rabbits through a longitudinal triangular scleral incision. No immunosuppressants were used. Retinal function was determined by electroretinogram analysis and retinal structure was determined by histological analysis and OCT. Transplanted cells were identified as a thin layer across the subretina and extravascular spaces of the choroid. In RCS rats, cell transplantation delayed photoreceptor degeneration across the entire retina and significantly enhanced retinal functions. No retinal detachment or choroidal hemorrhages were observed in rabbits following transplantation. This novel platform opens a new avenue for drug and cell delivery, placing the transplanted cells in close proximity to the damaged RPE and retina as a thin layer, across the subretina and thereby slowing down cell death and photoreceptor degeneration, without retinal detachment or choroidal hemorrhage. This new transplantation system may increase the therapeutic effect of other cell-based therapies and therapeutic agents. This study is expected to directly lead to phase I/II clinical trials for autologous hBM-MSCs transplantation in retinal degeneration patients.

  14. Retinal spot size with wavelength

    NASA Astrophysics Data System (ADS)

    Rockwell, Benjamin A.; Hammer, Daniel X.; Kennedy, Paul K.; Amnotte, Rodney E.; Eilert, Brent; Druessel, Jeffrey J.; Payne, Dale J.; Phillips, Shana L.; Stolarski, David J.; Noojin, Gary D.; Thomas, Robert J.; Cain, Clarence P.

    1997-06-01

    We have made an indirect in-vivo determination of spot size focusing in the rhesus monkey model. Measurement of the laser induced breakdown threshold both in-vitro and in-vivo allow correlation and assignment of a spot size after focusing through the living eye. We discuss and analyze the results and show how trends in minimum visible lesion data should be assessed in light of chromatic aberration. National laser safety standards are based on minimal visual lesion (MVL) threshold studies in different animal models. The energy required for a retinal lesion depends upon may parameters including wavelength and retinal spot size. We attempt to explain trends in reported MVL threshold studies using a model of the eye which allows calculation of changes in retinal spot size due to chromatic aberration.

  15. Clinical Trials in Retinal Dystrophies.

    PubMed

    Grob, Seanna R; Finn, Avni; Papakostas, Thanos D; Eliott, Dean

    2016-01-01

    Research development is burgeoning for genetic and cellular therapy for retinal dystrophies. These dystrophies are the focus of many research efforts due to the unique biology and accessibility of the eye, the transformative advances in ocular imaging technology that allows for in vivo monitoring, and the potential benefit people would gain from success in the field - the gift of renewed sight. Progress in the field has revealed the immense complexity of retinal dystrophies and the challenges faced by researchers in the development of this technology. This study reviews the current trials and advancements in genetic and cellular therapy in the treatment of retinal dystrophies and also discusses the current and potential future challenges. PMID:26957839

  16. Exploring the retinal connectome

    PubMed Central

    Anderson, James R.; Jones, Bryan W.; Watt, Carl B.; Shaw, Margaret V.; Yang, Jia-Hui; DeMill, David; Lauritzen, James S.; Lin, Yanhua; Rapp, Kevin D.; Mastronarde, David; Koshevoy, Pavel; Grimm, Bradley; Tasdizen, Tolga; Whitaker, Ross

    2011-01-01

    Purpose A connectome is a comprehensive description of synaptic connectivity for a neural domain. Our goal was to produce a connectome data set for the inner plexiform layer of the mammalian retina. This paper describes our first retinal connectome, validates the method, and provides key initial findings. Methods We acquired and assembled a 16.5 terabyte connectome data set RC1 for the rabbit retina at ≈2 nm resolution using automated transmission electron microscope imaging, automated mosaicking, and automated volume registration. RC1 represents a column of tissue 0.25 mm in diameter, spanning the inner nuclear, inner plexiform, and ganglion cell layers. To enhance ultrastructural tracing, we included molecular markers for 4-aminobutyrate (GABA), glutamate, glycine, taurine, glutamine, and the in vivo activity marker, 1-amino-4-guanidobutane. This enabled us to distinguish GABAergic and glycinergic amacrine cells; to identify ON bipolar cells coupled to glycinergic cells; and to discriminate different kinds of bipolar, amacrine, and ganglion cells based on their molecular signatures and activity. The data set was explored and annotated with Viking, our multiuser navigation tool. Annotations were exported to additional applications to render cells, visualize network graphs, and query the database. Results Exploration of RC1 showed that the 2 nm resolution readily recapitulated well known connections and revealed several new features of retinal organization: (1) The well known AII amacrine cell pathway displayed more complexity than previously reported, with no less than 17 distinct signaling modes, including ribbon synapse inputs from OFF bipolar cells, wide-field ON cone bipolar cells and rod bipolar cells, and extensive input from cone-pathway amacrine cells. (2) The axons of most cone bipolar cells formed a distinct signal integration compartment, with ON cone bipolar cell axonal synapses targeting diverse cell types. Both ON and OFF bipolar cells receive

  17. Rat retinal transcriptome

    PubMed Central

    Kozhevnikova, Oyuna S.; Korbolina, Elena E.; Ershov, Nikita I.; Kolosova, Natalia G.

    2013-01-01

    Pathogenesis of age-related macular degeneration (AMD), the leading cause of vision loss in the elderly, remains poorly understood due to the paucity of animal models that fully replicate the human disease. Recently, we showed that senescence-accelerated OXYS rats develop a retinopathy similar to human AMD. To identify alterations in response to normal aging and progression of AMD-like retinopathy, we compared gene expression profiles of retina from 3- and 18-mo-old OXYS and control Wistar rats by means of high-throughput RNA sequencing (RNA-Seq). We identified 160 and 146 age-regulated genes in Wistar and OXYS retinas, respectively. The majority of them are related to the immune system and extracellular matrix turnover. Only 24 age-regulated genes were common for the two strains, suggestive of different rates and mechanisms of aging. Over 600 genes showed significant differences in expression between the two strains. These genes are involved in disease-associated pathways such as immune response, inflammation, apoptosis, Ca2+ homeostasis and oxidative stress. The altered expression for selected genes was confirmed by qRT-PCR analysis. To our knowledge, this study represents the first analysis of retinal transcriptome from young and old rats with biologic replicates generated by RNA-Seq technology. We can conclude that the development of AMD-like retinopathy in OXYS rats is associated with an imbalance in immune and inflammatory responses. Aging alters the expression profile of numerous genes in the retina, and the genetic background of OXYS rats has a profound impact on the development of AMD-like retinopathy. PMID:23656783

  18. New Wrinkles in Retinal Densitometry

    PubMed Central

    Masella, Benjamin D.; Hunter, Jennifer J.; Williams, David R.

    2014-01-01

    Purpose. Retinal densitometry provides objective information about retinal function. But, a number of factors, including retinal reflectance changes that are not directly related to photopigment depletion, complicate its interpretation. We explore these factors and suggest a method to minimize their impact. Methods. An adaptive optics scanning light ophthalmoscope (AOSLO) was used to measure changes in photoreceptor reflectance in monkeys before and after photopigment bleaching with 514-nm light. Reflectance measurements at 514 nm and 794 nm were recorded simultaneously. Several methods of normalization to extract the apparent optical density of the photopigment were compared. Results. We identified stimulus-related fluctuations in 794-nm reflectance that are not associated with photopigment absorptance and occur in both rods and cones. These changes had a magnitude approaching those associated directly with pigment depletion, precluding the use of infrared reflectance for normalization. We used a spatial normalization method instead, which avoided the fluctuations in the near infrared, as well as a confocal AOSLO designed to minimize light from layers other than the receptors. However, these methods produced a surprisingly low estimate of the apparent rhodopsin density (animal 1: 0.073 ± 0.006, animal 2: 0.032 ± 0.003). Conclusions. These results confirm earlier observations that changes in photopigment absorption are not the only source of retinal reflectance change during dark adaptation. It appears that the stray light that has historically reduced the apparent density of cone photopigment in retinal densitometry arises predominantly from layers near the photoreceptors themselves. Despite these complications, this method provides a valuable, objective measure of retinal function. PMID:25316726

  19. Retinal Image Quality During Accommodation

    PubMed Central

    López-Gil, N.; Martin, J.; Liu, T.; Bradley, A.; Díaz-Muñoz, D.; Thibos, L.

    2013-01-01

    Purpose We asked if retinal image quality is maximum during accommodation, or sub-optimal due to accommodative error, when subjects perform an acuity task. Methods Subjects viewed a monochromatic (552nm), high-contrast letter target placed at various viewing distances. Wavefront aberrations of the accommodating eye were measured near the endpoint of an acuity staircase paradigm. Refractive state, defined as the optimum target vergence for maximising retinal image quality, was computed by through-focus wavefront analysis to find the power of the virtual correcting lens that maximizes visual Strehl ratio. Results Despite changes in ocular aberrations and pupil size during binocular viewing, retinal image quality and visual acuity typically remain high for all target vergences. When accommodative errors lead to sub-optimal retinal image quality, acuity and measured image quality both decline. However, the effect of accommodation errors of on visual acuity are mitigated by pupillary constriction associated with accommodation and binocular convergence and also to binocular summation of dissimilar retinal image blur. Under monocular viewing conditions some subjects displayed significant accommodative lag that reduced visual performance, an effect that was exacerbated by pharmacological dilation of the pupil. Conclusions Spurious measurement of accommodative error can be avoided when the image quality metric used to determine refractive state is compatible with the focusing criteria used by the visual system to control accommodation. Real focusing errors of the accommodating eye do not necessarily produce a reliably measurable loss of image quality or clinically significant loss of visual performance, probably because of increased depth-of-focus due to pupil constriction. When retinal image quality is close to maximum achievable (given the eye’s higher-order aberrations), acuity is also near maximum. A combination of accommodative lag, reduced image quality, and reduced

  20. Retinal Optical Coherence Tomography Imaging

    NASA Astrophysics Data System (ADS)

    Drexler, Wolfgang; Fujimoto, James G.

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

  1. Acute Hemorrhagic Edema of Infancy.

    PubMed

    Serra E Moura Garcia, C; Sokolova, A; Torre, M L; Amaro, C

    2016-01-01

    Acute Hemorrhagic Edema of Infancy is a small vessel leucocytoclastic vasculitis affecting young infants. It is characterized by large, target-like, macular to purpuric plaques predominantly affecting the face, ear lobes and extremities. Non-pitting edema of the distal extremities and low-grade fever may also be present. Extra-cutaneous involvement is very rare. Although the lesions have a dramatic onset in a twenty-four to forty-eight hour period, usually the child has a non-toxic appearance. In most cases there are no changes in laboratory parameters. The cutaneous biopsy reveals an inflammatory perivascular infiltrate. It is a benign and auto-limited disease, with complete resolution within two to three weeks leaving no sequelae in the majority of cases. No recurrences are described. We report a case of a 42-day old girl admitted at our hospital with Acute Hemorrhagic Edema of Infancy.

  2. Comparative retinal physiology in anthropoids.

    PubMed

    Kremers, J; Lee, B B

    1998-11-01

    During the last decade it has become clear that colour vision in platyrrhines (New World monkeys) differs from the uniform trichromatic pattern normally found in catarrhines (Old World monkeys, apes and human). Colour vision in most platyrrhine species is polymorphic, with many dichromatic individuals. The comparison of response properties in retinal ganglion cells and lateral geniculate cells between catarrhines and playrrhines elucidates how the evolution of trichromatic colour vision influenced the post-receptoral processing. We find that spatial and temporal processing is very similar in the platyrrhine and catarrhine retina, strongly suggesting that the retinal structure and function, found in living anthropoids, was already present in their common ancestor. PMID:9893846

  3. Retinitis pigmentosa in southern Africa.

    PubMed

    Greenberg, J; Bartmann, L; Ramesar, R; Beighton, P

    1993-11-01

    Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal disorders which are a common cause of genetic blindness. The relative frequencies of the different forms of RP in South Africa, as determined from the register at the DNA banking centre for RP at the Department of Human Genetics, University of Cape Town, are presented and discussed. Of the 125 families analysed, 29 (23%) showed autosomal dominant, 33 (27%) autosomal recessive and 3 (3%) X-linked inheritance. In 10 families the pedigree data were insufficient to allow accurate genetic subtyping and a further 50 patients were sporadic without a family history of RP or other syndromic features which would allow categorization.

  4. Imaging of adrenal and renal hemorrhage.

    PubMed

    Hammond, Nancy A; Lostumbo, Antonella; Adam, Sharon Z; Remer, Erick M; Nikolaidis, Paul; Yaghmai, Vahid; Berggruen, Senta M; Miller, Frank H

    2015-10-01

    Hemorrhage of the kidneys and adrenal glands has many etiologies. In the adrenal glands, trauma, anticoagulation, stress, sepsis, surgery, and neoplasms are common causes of hemorrhage. In the kidneys, reasons for hemorrhage include trauma, bleeding diathesis, vascular diseases, infection, infarction, hemorrhagic cyst rupture, the Antopol-Goldman lesion, and neoplasms. Angiomyolipoma and renal cell carcinoma are the neoplasms most commonly associated with hemorrhage in the kidneys and adrenal cortical carcinoma, metastases, and pheochromocytoma are associated with hemorrhage in the adrenal glands. Understanding the computed tomography and magnetic resonance imaging features, and causes of hemorrhage in the kidneys and adrenal glands is critical. It is also important to keep in mind that mimickers of hemorrhage exist, including lymphoma in both the kidneys and adrenal glands, and melanoma metastases in the adrenal glands. Appropriate imaging follow-up of renal and adrenal hemorrhage should occur to exclude an underlying malignancy as the cause. If there is suspicion for malignancy that cannot be definitively diagnosed on imaging, surgery or biopsy may be warranted. Angiography may be indicated when there is a suspected underlying vascular disease. Unnecessary intervention, such as nephrectomy, may be avoided in patients with benign causes or no underlying disease. Appropriate management is dependent on accurate diagnosis of the cause of renal or adrenal hemorrhage and it is incumbent upon the radiologist to determine the etiology.

  5. [Impact of anti-VEGF therapy on the cellular microenvironment in retinal angiogenesis].

    PubMed

    Nakao, Shintaro

    2014-11-01

    Various large-scale studies show the efficacy of anti-vascular endothelial growth factor (VEGF) therapy in treatment of retinal diseases. Based on the evidence, it is expected that this therapeutic strategy will be used widely for various retinal vascular diseases including diabetic retinopathy and retinal vein occlusion. Leukocyte infiltration is an important step that occurs during angiogenesis in inflammatory diseases. Various studies report that infiltrated leukocytes are a prerequisite for retinal angiogenesis, including diabetic retinopathy. Furthermore, the fibrovascular membrane (FVM) microenvironment consists of stromal components (extracellular matrix, myofibroblasts and leukocytes) supported by angiogenesis (endothelial cells and pericytes). The activity of proliferative diabetic retinopathy (PDR) is thought to be determined by the angiogenesis-assisted FVM microenvironment status. Recently, we investigated whether intravitreal anti-VEGF therapy modulates leukocyte infiltration in retinal angiogenesis using the surgically obtained FVM in pars plana vitrectomy with or without pretreatment with bevacizumab. The effect of anti-VEGF therapy on leukocyte infiltration was also examined with a mouse model of oxygen-induced retinopathy. Moreover, the impact of anti-VEGF therapy on endothelial cells, pericytes and myofibroblasts was also examined using the FVM. We could observe that anti-VEGF therapy blocked leukocyte infiltration as well as re-entry from the retina. The therapy also could induce the contraction of blood vessels, increasing the pericyte ratio and transforming growth factor-β expression in the FVM. Our data indicate anti-VEGF therapy could attain anti-inflammation, vessel contraction and vessel maturation, resulting in the resolution of retinal edema as well as the prevention of intraoperative hemorrhage.

  6. Dabigatran-Associated Intracranial Hemorrhage

    PubMed Central

    Szarlej, Dorota K.; Rincon, Fred

    2015-01-01

    Dabigatran etexilate is an oral direct thrombin inhibitor approved for prevention of stroke and systemic embolization in patients with nonvalvular atrial fibrillation and for the treatment of venous thromboembolism. Although dabigatran has a favorable safety profile, predictable pharmacokinetics, fewer drug interactions than warfarin, and does not require monitoring, clinical data regarding dabigatran reversal are limited. In addition, currently available laboratory assays allow measurement of the presence, but not extent, of dabigatran-associated anticoagulation. Patient age, renal function, weight, concurrent drug therapy, adherence, and concomitant disease states can affect dabigatran’s efficacy and safety. Management of dabigatran-related intracranial hemorrhage must be approached on a case-by-case basis and include assessment of degree of anticoagulation, severity of hemorrhage, renal function, timing of last dabigatran dose, and risk of thromboembolic events. Initial management includes dabigatran discontinuation and general supportive measures. Oral activated charcoal should be administered in those who ingested dabigatran within 2 hours. Four-factor prothrombin complex concentrates (4PCCs), activated PCC, or recombinant activated factor VII use may be reasonable but is not evidence based. Reserve fresh frozen plasma for patients with dilutional coagulopathy. If readily available, hemodialysis should be considered, particularly in patients with advanced kidney injury or excessive risk of thromboembolic events. More clinical studies are needed to determine a standardized approach to treating dabigatran-associated intracranial hemorrhage. Institutional protocol development will facilitate safe, efficacious, and timely use of the limited management options. PMID:26425251

  7. ACUTE RETINAL ARTERIAL OCCLUSIVE DISORDERS

    PubMed Central

    Hayreh, Sohan Singh

    2011-01-01

    The initial section deals with basic sciences; among the various topics briefly discussed are the anatomical features of ophthalmic, central retinal and cilioretinal arteries which may play a role in acute retinal arterial ischemic disorders. Crucial information required in the management of central retinal artery occlusion (CRAO) is the length of time the retina can survive following that. An experimental study shows that CRAO for 97 minutes produces no detectable permanent retinal damage but there is a progressive ischemic damage thereafter, and by 4 hours the retina has suffered irreversible damage. In the clinical section, I discuss at length various controversies on acute retinal arterial ischemic disorders. Classification of acute retinal arterial ischemic disorders These are of 4 types: CRAO, branch retinal artery occlusion (BRAO), cotton wools spots and amaurosis fugax. Both CRAO and BRAO further comprise multiple clinical entities. Contrary to the universal belief, pathogenetically, clinically and for management, CRAO is not one clinical entity but 4 distinct clinical entities – non-arteritic CRAO, non-arteritic CRAO with cilioretinal artery sparing, arteritic CRAO associated with giant cell arteritis (GCA) and transient non-arteritic CRAO. Similarly, BRAO comprises permanent BRAO, transient BRAO and cilioretinal artery occlusion (CLRAO), and the latter further consists of 3 distinct clinical entities - non-arteritic CLRAO alone, non-arteritic CLRAO associated with central retinal vein occlusion and arteritic CLRAO associated with GCA. Understanding these classifications is essential to comprehend fully various aspects of these disorders. Central retinal artery occlusion The pathogeneses, clinical features and management of the various types of CRAO are discussed in detail. Contrary to the prevalent belief, spontaneous improvement in both visual acuity and visual fields does occur, mainly during the first 7 days. The incidence of spontaneous visual

  8. A novel method for retinal exudate segmentation using signal separation algorithm.

    PubMed

    Imani, Elaheh; Pourreza, Hamid-Reza

    2016-09-01

    Diabetic retinopathy is one of the major causes of blindness in the world. Early diagnosis of this disease is vital to the prevention of visual loss. The analysis of retinal lesions such as exudates, microaneurysms and hemorrhages is a prerequisite to detect diabetic disorders such as diabetic retinopathy and macular edema in fundus images. This paper presents an automatic method for the detection of retinal exudates. The novelty of this method lies in the use of Morphological Component Analysis (MCA) algorithm to separate lesions from normal retinal structures to facilitate the detection process. In the first stage, vessels are separated from lesions using the MCA algorithm with appropriate dictionaries. Then, the lesion part of retinal image is prepared for the detection of exudate regions. The final exudate map is created using dynamic thresholding and mathematical morphologies. Performance of the proposed method is measured on the three publicly available DiaretDB, HEI-MED and e-ophtha datasets. Accordingly, the AUC of 0.961 and 0.948 and 0.937 is achieved respectively, which are greater than most of the state-of-the-art methods.

  9. Prospects of Stem Cells for Retinal Diseases.

    PubMed

    Ng, Tsz Kin; Lam, Dennis S C; Cheung, Herman S

    2013-01-01

    Retinal diseases, including glaucoma, retinitis pigmentosa, diabetic retinopathy, and age-related macular degeneration, are the leading causes of irreversible visual impairment and blindness in developed countries. Traditional and current treatment regimens are based on surgical or medical interventions to slow down the disease progression. However, the number of retinal cells would continue to diminish, and the diseases could not be completely cured. There is an emerging role of stem cells in retinal research. The stem cell therapy on retinal diseases is based on 2 theories: cell replacement therapy and neuroprotective effect. The former hypothesizes that new retinal cells could be regenerated from stem cells to substitute the damaged cells in the diseased retina, whereas the latter believes that the paracrine effects of stem cells modulate the microenvironments of the diseased retina so as to protect the retinal neurons. This article summarizes the choice of stem cells in retinal research. Moreover, the current progress of retinal research on stem cells and the clinical applications of stem cells on retinal diseases are reviewed. In addition, potential challenges and future prospects of retinal stem cell research are discussed.

  10. [Progress of research in retinal image registration].

    PubMed

    Yu, Lun; Wei, Lifang; Pan, Lin

    2011-10-01

    The retinal image registration has important applications in the processes of auxiliary diagnosis and treatment for a variety of diseases. The retinal image registration can be used to measure the disease process and the therapeutic effect. A variety of retinal image registration techniques have been studied extensively in recent years. However, there are still many problems existing and there are numerous research possibilities. Based on extensive investigation of existing literatures, the present paper analyzes the feature of retinal image and current challenges of retinal image registration, and reviews the transformation models of the retinal image registration technology and the main research algorithms in current retinal image registration, and analyzes the advantages and disadvantages of various types of algorithms. Some research challenges and future developing trends are also discussed.

  11. Subarachnoid hemorrhage and cerebral vasospasm - literature review.

    PubMed

    Ciurea, A V; Palade, C; Voinescu, D; Nica, D A

    2013-06-15

    Subarachnoid hemorrhage represents a serious disease with high mortality and morbidity. Two important areas are becoming the central research interest of subarachnoid hemorrhage: cerebral vasospasm and early brain injury. The authors have reviewed the major contributions in experimental subarachnoid hemorrhage documented in the medical literature in the past 5 years. Treatments interfering with nitric oxide - or endothelin-pathways continue to show antispasmotic effects in experimental models of subarachnoid hemorrhage. Inflammation and oxidative stress play a vital role in the pathophysiology of cerebral vasospasm. Apoptosis, a relevant cause of early brain injury after subarachnoid hemorrhage, also underline the etiology of cerebral vasospasm. Future research studies will continue to elucidate the pathophysiological pathways and treatment modalities targeting cerebral vasospasm and early brain injury, enabling an improvement in outcome for patients with subarachnoid hemorrhage. PMID:23904869

  12. A Degenerative Retinal Process in HIV-Associated Non-Infectious Retinopathy

    PubMed Central

    Freeman, William R.; Sprague, L. James; Gomez, Maria Laura; Cheng, Lingyun; El-Emam, Sharif; Mojana, Francesca; Bartsch, Dirk-Uwe; Bosten, Jenny; Ayyagari, Radha; Hardiman, Gary

    2013-01-01

    HIV retinopathy is the most common non-infectious complication in the eyes of HIV-positive individuals. Oncotic lesions in the retinal nerve fiber layer, referred to as cotton wool spots (CWS), and intraretinal (IR) hemorrhages are frequently observed but are not unique to this pathology. HIV-positive patients have impaired color vision and contrast sensitivity, which worsens with age. Evidence of inner–retinal lesions and damage have been documented ophthalmoscopically, however their long term structural effect has not been investigated. It has been hypothesized that they may be partially responsible for loss of visual function and visual field. In this study we utilized clinical data, retinal imaging and transcriptomics approaches to comprehensively interrogate non-infectious HIV retinopathy. The methods employed encompassed clinical examinations, fundus photography, indirect ophthalmoscopy, Farmsworth-Munsell 100 hue discrimination testing and Illumina BeadChip analyses. Here we show that changes in the outer retina, specifically in the retinal pigment epithelium (RPE) and photoreceptor outer segments (POS) contribute to vision changes in non-infectious HIV retinopathy. We find that in HIV-positive retinae there is an induction of rhodopsin and other transcripts (including PDE6A, PDE6B, PDE6G, CNGA1, CNGB1, CRX, NRL) involved in visual transduction, as well as structural components of the rod photoreceptors (ABCA4 and ROM1). This is consistent with an increased rate of renewal of rod outer segments induced via increased phagocytosis by HIV-infected RPE previously reported in culture. Cone-specific transcripts (OPN1SW, OPN1LW, PDE6C, PDE6H and GRK7) are uniformly downregulated in HIV positive retina, likely due to a partial loss of cone photoreceptors. Active cotton wool spots and intraretinal hemorrhages (IRH) may not affect photoreceptors directly and the interaction of photoreceptors with the aging RPE may be the key to the progressive vision changes in HIV

  13. Case report of atypical hemolytic uremic syndrome with retinal arterial and venous occlusion treated with eculizumab

    PubMed Central

    Greenwood, Gregory T

    2015-01-01

    Atypical hemolytic uremic syndrome (aHUS) is a rare disease caused by chronic, uncontrolled activation of the alternative complement pathway, leading to thrombotic microangiopathy. Renal impairment and progression to end-stage renal disease are common in untreated patients with aHUS, and extrarenal manifestations are being increasingly characterized in the literature. Ocular involvement remains rare in aHUS. This report describes a patient with aHUS with bilateral central retinal artery and vein occlusion, vitreous hemorrhage, and blindness in addition to renal impairment. The patient’s hematologic and renal parameters and ocular manifestation improved following initiation of eculizumab therapy. PMID:26508891

  14. Electroretinography combined with spectral domain optical coherence tomography to detect retinal damage in shaken baby syndrome.

    PubMed

    Nakayama, Yuri; Yokoi, Tadashi; Sachiko, Nishina; Okuyama, Makiko; Azuma, Noriyuki

    2013-08-01

    In order to correlate anatomical changes with visual function in shaken baby syndrome, we performed electroretinography and spectral domain optical coherence tomography on a 2-month-old girl and a 9-month-old girl after the retinal hemorrhages absorbed. Both patients had significant abnormalities in spectral domain optical coherence tomography images of the macular area. The amplitudes of the focal macular electroretinograms were more severely decreased than those of the full-field electroretinograms. Combining spectral domain coherence tomography with focal macular electroretinograms might better estimate the functional damage to the macula in patients with shaken baby syndrome.

  15. Vision Loss Caused by Retinal and Lateral Geniculate Nucleus Infarction in H1N1 Influenza.

    PubMed

    Breker, Dane A; Stacey, Andrew W; Srinivasan, Ashok; Bursztyn, Lulu L C D; Trobe, Jonathan D; Johnson, Mark W

    2015-09-01

    A 13-year-old girl developed encephalopathy and severe bilateral vision loss to the level of light perception within 24 hours of having fever and myalgias heralding H1N1 influenza A. Ophthalmoscopy demonstrated findings of confluent ischemic retinopathy. Brain MRI disclosed lateral geniculate body signal abnormalities indicative of hemorrhagic infarction. Despite aggressive treatment with intravenous corticosteroids, intravenous immunoglobulin, and plasmapheresis, vision did not substantially improve. This case demonstrates that H1N1 can cause simultaneous retinal and lateral geniculate body infarctions, a combination of findings not previously described in any condition. We postulate an immunologic response to the virus marked by occlusive damage to arteriolar endothelium. PMID:25887303

  16. Retinitis Pigmentosa and Education Issues

    ERIC Educational Resources Information Center

    Brown, Thomas J.

    2005-01-01

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

  17. Automatic temperature controlled retinal photocoagulation

    NASA Astrophysics Data System (ADS)

    Schlott, Kerstin; Koinzer, Stefan; Ptaszynski, Lars; Bever, Marco; Baade, Alex; Roider, Johann; Birngruber, Reginald; Brinkmann, Ralf

    2012-06-01

    Laser coagulation is a treatment method for many retinal diseases. Due to variations in fundus pigmentation and light scattering inside the eye globe, different lesion strengths are often achieved. The aim of this work is to realize an automatic feedback algorithm to generate desired lesion strengths by controlling the retinal temperature increase with the irradiation time. Optoacoustics afford non-invasive retinal temperature monitoring during laser treatment. A 75 ns/523 nm Q-switched Nd:YLF laser was used to excite the temperature-dependent pressure amplitudes, which were detected at the cornea by an ultrasonic transducer embedded in a contact lens. A 532 nm continuous wave Nd:YAG laser served for photocoagulation. The ED50 temperatures, for which the probability of ophthalmoscopically visible lesions after one hour in vivo in rabbits was 50%, varied from 63°C for 20 ms to 49°C for 400 ms. Arrhenius parameters were extracted as ΔE=273 J mol-1 and A=3.1044 s-1. Control algorithms for mild and strong lesions were developed, which led to average lesion diameters of 162+/-34 μm and 189+/-34 μm, respectively. It could be demonstrated that the sizes of the automatically controlled lesions were widely independent of the treatment laser power and the retinal pigmentation.

  18. Pulmonary hemorrhage resulting from bungee jumping.

    PubMed

    Manos, Daria; Hamer, Okka; Müller, Nestor L

    2007-11-01

    Pulmonary hemorrhage is a relatively common complication of blunt chest trauma. Occasionally, it may result from pulmonary barotrauma after scuba diving or from sports activities not associated with barotrauma such as long breath-hold diving. We report a case of symmetric diffuse upper lobe hemorrhage resulting from a bungee jump in a previously healthy man. Bungee jumping is an increasingly popular sport with relatively few reported injuries. To our knowledge pulmonary hemorrhage in this setting has not yet been described.

  19. Viral hemorrhagic fevers of South America.

    PubMed

    Tesh, Robert B

    2002-09-01

    This paper reviews the epidemiology and distinguishing features of three viral hemorrhagic fevers (dengue hemorrhagic fever, yellow fever and arenaviral hemorrhagic fever) that have emerged as important public health problems in South America. Although the etiology, natural history and control of the three diseases are different, their clinical manifestations and histopathology findings are similar and can be difficult to differentiate. Consequently, early recognition and correct diagnosis are essential for effective control measures to be initiated.

  20. Hemorrhagic cystitis: A challenge to the urologist

    PubMed Central

    Manikandan, R.; Kumar, Santosh; Dorairajan, Lalgudi N.

    2010-01-01

    Severe hemorrhagic cystitis often arises from anticancer chemotherapy or radiotherapy for pelvic malignancies. Infectious etiologies are less common causes except in immunocompromised hosts. These cases can be challenging problems for the urologist and a source of substantial morbidity and sometimes mortality for the patients. A variety of modalities of treatment have been described for the management of hemorrhagic cystitis but there is none that is uniformly effective. Some progress has been made in the understanding and management of viral hemorrhagic cystitis. This article reviews the common causes of severe hemorrhagic cystitis and the currently available management options. PMID:20877590

  1. Spontaneous Massive Adrenal Hemorrhage: A Management Dilemma

    PubMed Central

    Agarwal, Anshuman

    2015-01-01

    Abstract Adrenal hemorrhage (AH) is a rare but life-threatening condition. Small focal hemorrhage may present subclinically, but massive hemorrhage may lead to rapid cardiovascular collapse and ultimately death if not diagnosed appropriately and treated quickly. Most cases reported in the literature have been treated conservatively. In an event of increasing hemorrhage during conservative management, it may be tricky to intervene surgically because of the hematoma around the gland. Here we describe a case where we managed a large spontaneous AH by a combination of angioembolization and laparoscopic adrenalectomy.

  2. Spontaneous Massive Adrenal Hemorrhage: A Management Dilemma

    PubMed Central

    Agarwal, Anshuman

    2015-01-01

    Abstract Adrenal hemorrhage (AH) is a rare but life-threatening condition. Small focal hemorrhage may present subclinically, but massive hemorrhage may lead to rapid cardiovascular collapse and ultimately death if not diagnosed appropriately and treated quickly. Most cases reported in the literature have been treated conservatively. In an event of increasing hemorrhage during conservative management, it may be tricky to intervene surgically because of the hematoma around the gland. Here we describe a case where we managed a large spontaneous AH by a combination of angioembolization and laparoscopic adrenalectomy. PMID:27579389

  3. Hepatic hemorrhage in malignant rheumatoid arthritis.

    PubMed

    Mizuno, K; Ikeda, K; Saida, Y; Takenaka, R; Shibata, M; Takeuchi, T

    1996-12-01

    Intrahepatic hemorrhage is a serious and life-threatening complication in liver disease. We describe a patient who had two episodes of intrahepatic hemorrhage after having malignant rheumatoid arthritis for 8 yr. Abdominal CT scans revealed a large intrahepatic, subcapsular hematoma. Arteriography demonstrated irregularity, caliber change, and pseudoaneurysms of the right hepatic artery, suggesting vasculitis as a cause of the bleeding. The hemorrhage was first treated with transcatheter arterial embolization, which failed to exert long term control, but arterial infusion of a large dose of prednisolone when the hemorrhage appeared was successful in managing it.

  4. Retinal vasculature classification using novel multifractal features

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

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

  5. Propylthiouracil-induced alveolar hemorrhage

    PubMed Central

    Aydın, Bünyamin; Aksu, Oğuzhan; Kacemer, Hasret; Demirkan, Halil; Altuntaş, Atilla; Dirican, Nigar; Köroğlu, Banu Kale; Şahin, Mehmet

    2015-01-01

    Thionamide induced vasculitis is a multisystem disease. The patients may present with different clinical signs and findings due to organ involvement. These patients are almost always perinuclear antineutrophil cytoplasmic antibody (pANCA) or antimyeloperoxidase (MPO) positive. Clinical findings are not seen in all of the patients who are ANCA positive while using thionamide. Although symptoms usually resolve with drug discontinuation, some patients, however, require high-dose steroids, immunosuppressants, or plasmapheresis. We present here a case of alveolar hemorrhage induced by propilthiouracil (PTU) during treatment with PTU for Graves’ disease; patients completely recovered with corticosteroid, cyclophosphamide, and plasmapheresis.

  6. Adiposity and ischemic and hemorrhagic stroke

    PubMed Central

    Kroll, Mary E.; Green, Jane; Beral, Valerie; Sudlow, Cathie L.M.; Brown, Anna; Kirichek, Oksana; Price, Alison; Yang, TienYu Owen

    2016-01-01

    Objective: To compare associations of body mass index (BMI) with ischemic stroke and hemorrhagic stroke risk, and to review the worldwide evidence. Methods: We recruited 1.3 million previously stroke-free UK women between 1996 and 2001 (mean age 57 years [SD 5]) and followed them by record linkage for hospital admissions and deaths. We used Cox regression to estimate adjusted relative risks for ischemic and hemorrhagic (intracerebral or subarachnoid hemorrhage) stroke in relation to BMI. We conducted a meta-analysis of published findings from prospective studies on these associations. Results: During an average follow-up of 11.7 years, there were 20,549 first strokes, of which 9,993 were specified as ischemic and 5,852 as hemorrhagic. Increased BMI was associated with an increased risk of ischemic stroke (relative risk 1.21 per 5 kg/m2 BMI, 95% confidence interval 1.18–1.23, p < 0.0001) but a decreased risk of hemorrhagic stroke (relative risk 0.89 per 5 kg/m2 BMI, 0.86–0.92, p < 0.0001). The BMI-associated trends for ischemic and hemorrhagic stroke were significantly different (heterogeneity: p < 0.0001) but were not significantly different for intracerebral hemorrhage (n = 2,790) and subarachnoid hemorrhage (n = 3,062) (heterogeneity: p = 0.5). Published data from prospective studies showed consistently greater BMI-associated relative risks for ischemic than hemorrhagic stroke with most evidence (prior to this study) coming from Asian populations. Conclusions: In UK women, higher BMI is associated with increased risk of ischemic stroke but decreased risk of hemorrhagic stroke. The totality of the available published evidence suggests that BMI-associated risks are greater for ischemic than for hemorrhagic stroke. PMID:27605176

  7. Retinal vascular changes in hypertensive patients in Ibadan, Sub-Saharan Africa

    PubMed Central

    Oluleye, Sunday Tunji; Olusanya, Bolutife Ayokunu; Adeoye, Abiodun Moshood

    2016-01-01

    Background Earlier studies in Nigeria reported the rarity of retinal vascular changes in hypertensives. The aim of this study was to describe the various retinal vascular changes in the hypertensive patients of Nigeria. Patients and methods Nine hundred and three hypertensive patients were studied. This study was approved by the ethical and research committee of the University of Ibadan and University College Hospital, Ibadan, Nigeria. Blood pressure and anthropometric measurements were measured. Cardiac echocardiography was performed on 156 patients. All patients had dilated fundoscopy and fundus photography using the Kowa portable fundus camera and an Apple iPhone with 20 D lens. Statistical analysis was done with Statistical Packages for the Social Sciences (Version 21). Results The mean age of patients was 57 years with a male:female ratio of 1. No retinopathy was found in 556 (61.5%) patients. In all, 175 (19.4%) patients had features of hypertensive retinopathy. Retinal vascular occlusion was a significant finding in 121 patients (13.4%), of which branch retinal vein occlusion, 43 (4.7%), and central retinal vein occlusion, 30 (3.3%), were the most prominent ones in cases. Hemicentral retinal vein occlusion, 26 (2.9%), and central retinal artery occlusion, 17 (1.9%), were significant presentations. Other findings included nonarteritic anterior ischemic optic neuropathy in five (0.6%) patients, hypertensive choroidopathy in seven (0.8%) patients, and hemorrhagic choroidal detachment in five (0.6%) patients. Left ventricular (LV) geometry was abnormal in 85 (55.5%) patients. Concentric remodeling, eccentric hypertrophy, and concentric hypertrophy were observed in 43 (27.6%), 26 (17.2%), and 15 (9.7%) patients, respectively. LV hypertrophy was found in 42 (27%) patients, while 60 (39%) patients had increased relative wall thickness. In this study, bivariate analysis showed a correlation between LV relative wall thickness and severity of retinopathy in both eyes

  8. Rebleeding after aneurysmal subarachnoid hemorrhage.

    PubMed

    Starke, R M; Connolly, E S

    2011-09-01

    Rebleeding after initial aneurysmal subarachnoid hemorrhage (SAH) can have substantial impact on overall patient outcome. While older studies have suggested rebleeding occurs in about 4% of patients during the first day after initial aneurysmal bleed, these studies may have failed to capture very early rebleeds and, consequently, underestimated the impact of rebleeding. An electronic literature search was performed to identify English-language articles published or available for review from February 1975 through October 2010. A total of 43 articles (40 original research and 3 review articles) focused on rebleeding after initial aneurysmal SAH in humans were selected for review. Although most studies supported an incidence of rebleeding ≤4%, studies investigating ultra-early rebleeding reported bleeding within the first 24 h following aneurysmal SAH in as many as 9-17% of patients, with most cases occurring within 6 h of initial hemorrhage. Overall, studies investigating antifibrinolytic therapy to reduce rebleeding have failed to clearly demonstrate overall therapeutic benefit. Short-course antifibrinolytic therapy may have a role prior to initial aneurysm repair, although insufficient data are currently available. PMID:21761274

  9. Subchorionic hemorrhage treatment with dydrogesterone.

    PubMed

    Pelinescu-Onciul, Dimitrie

    2007-10-01

    The objective of the study was to evaluate the efficacy of progestogenic therapy for the prevention of spontaneous abortions in patients with subchorionic hemorrhage. One hundred pregnant women with bleeding and ultrasonographic evidence of subchorionic hematoma were treated with oral dydrogesterone 40 mg/day. Only cases in which the embryo was viable were included. The follow-up included ultrasonography and intravaginal examination. Of the 100 pregnancies, 93 had a favorable evolution with maintenance of pregnancy. The abortion rate was therefore 7%. This compares with an abortion rate of 18.7% obtained in a previous study in women with subchorionic hematoma treated with micronized progesterone. The abortion rate was therefore reduced by up to 37% with dydrogesterone, as most cases had large-volume hematomas at the first visit and thus a poor prognosis. In conclusion, the marked immunomodulatory effect of dydrogesterone in maintaining a T helper-2 cytokine balance means that it is a good choice for preventing abortion in women suffering from subchorionic hemorrhage. PMID:17943544

  10. Epizootic hemorrhagic disease in a yak

    PubMed Central

    Raabis, Sarah M.; Byers, Stacey R.; Han, Sushan; Callan, Robert J.

    2014-01-01

    Epizootic hemorrhagic disease virus (EHDV) infection was diagnosed in a 3-year-old yak. The yak had signs of intermittent tremors, dysphagia, oral ulcerative lesions, hemorrhagic enteritis, tachypnea, and thrombocytopenia. Postmortem diagnostics confirmed EHDV (serotype 2) using reverse-transcriptase polymerase chain reaction (RT-PCR). Gross and histopathological results were consistent with EHDV reported in other species. PMID:24688138

  11. Postpartum hemorrhage: use of hemostatic combat gauze.

    PubMed

    Schmid, Bernd C; Rezniczek, Günther A; Rolf, Norbert; Maul, Holger

    2012-01-01

    Cheap and simple interventions that are intended to minimize postpartum hemorrhage are of major public health concern. We report a case of postpartum hemorrhage in which conservative interventions had failed. The use of a chitosan-covered gauze that originally was developed for combat trauma allowed us to achieve hemostasis, and a seemingly inevitable hysterectomy was avoided. PMID:22011588

  12. Surgical Outcomes of Hemorrhagic Metastatic Brain Tumors

    PubMed Central

    Yoo, Heon; Jung, Eugene; Gwak, Ho Shin; Shin, Sang Hoon

    2011-01-01

    Purpose Hemorrhagic metastatic brain tumors are not rare, but little is known about the surgical outcome following treatment. We conducted this study to determine the result of the surgical outcome of hemorrhagic metastatic brain tumors. Materials and Methods From July 2001 to December 2008, 21 patients underwent surgery for hemorrhagic metastatic brain tumors at our institution. 15 patients had lung cancer, 3 had hepatocellular carcinoma, and the rest had rectal cancer, renal cell carcinoma, and sarcoma. 20 patients had macroscopic hemorrhage in the tumors, and one patient had intracerebral hemorrhage surrounding the tumor. A retrospective clinical review was conducted focusing on the patterns of presenting symptoms and signs, as well as local recurrence following surgery. Results Among 21 hemorrhagic brain metastases, local recurrence developed in two patients. The 12 month progression free survival rate was 86.1%. Mean time to progression was 20.8 months and median survival time after surgery was 11.7 months. Conclusion The results of our study showed that hemorrhagic metastatic brain tumors rarely recurred after surgery. Surgery should be considered as a good treatment option for hemorrhagic brain metastasis, especially in cases with increased intracranial pressure or severe neurologic deficits. PMID:21811426

  13. Spontaneous Retroperitoneal Hemorrhage from Adrenal Artery Aneurysm

    SciTech Connect

    Gonzalez Valverde, F.M. Balsalobre, M.; Torregrosa, N.; Molto, M.; Gomez Ramos, M.J.; Vazquez Rojas, J.L.

    2007-04-15

    Spontaneous adrenal hemorrhage is a very rare but serious disorder of the adrenal gland that can require emergent treatment. We report on a 42-year-old man who underwent selective angiography for diagnosis and treatment of retroperitoneal hemorrhage from small adrenal artery aneurysm. This case gives further details about the value of transluminal artery embolization in the management of visceral aneurysm rupture.

  14. First outbreak of dengue hemorrhagic fever, Bangladesh.

    PubMed

    Rahman, Mahbubur; Rahman, Khalilur; Siddque, A K; Shoma, Shereen; Kamal, A H M; Ali, K S; Nisaluk, Ananda; Breiman, Robert F

    2002-07-01

    During the first countrywide outbreak of dengue hemorrhagic fever in Bangladesh, we conducted surveillance for dengue at a hospital in Dhaka. Of 176 patients, primarily adults, found positive for dengue, 60.2% had dengue fever, 39.2% dengue hemorrhagic fever, and 0.6% dengue shock syndrome. The Dengue virus 3 serotype was detected in eight patients.

  15. Upper gastrointestinal hemorrhage caused by superwarfarin poisoning

    PubMed Central

    Zhao, Shu-Lei; Li, Peng; Ji, Ming; Zong, Ye; Zhang, Shu-Tian

    2010-01-01

    Superwarfarins are a class of rodenticides. Gastrointestinal hemorrhage is a fatal complication of superwarfarin poisoning, requiring immediate treatment. Here, we report a 55-year-old woman with tardive upper gastrointestinal hemorrhage caused by superwarfarin poisoning after endoscopic cold mucosal biopsy. PMID:20355251

  16. Current perspectives of herpesviral retinitis and choroiditis.

    PubMed

    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

  17. The progressive outer retinal necrosis syndrome.

    PubMed

    Holland, G N

    1994-01-01

    The progressive outer retinal necrosis (PORN) syndrome is a recently described clinical variant of necrotizing herpetic retinopathy in patients with the acquired immunodeficiency syndrome (AIDS). It is caused by varicellazoster virus infection of the retina. Its course and clinical features distinguish it from the acute retinal necrosis syndrome and CMV retinopathy. Early disease is characterized by multifocal deep retinal opacification. Lesions rapidly coalesce and progress to total retinal necrosis over a short period of time. Despite aggressive therapy with intravenous antivirial drugs, prognosis is poor; disease progression and/or recurrence is common, and the majority of patients develop no light perception vision. Total retinal detachments are common. Prophylaxis against retinal detachment using laser retinopexy has not been useful in most cases. PORN syndrome is an uncommon, but devastating complication of AIDS.

  18. Current perspectives of herpesviral retinitis and choroiditis.

    PubMed

    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.

  19. Retinal blood vessels extraction using probabilistic modelling.

    PubMed

    Kaba, Djibril; Wang, Chuang; Li, Yongmin; Salazar-Gonzalez, Ana; Liu, Xiaohui; Serag, Ahmed

    2014-01-01

    The analysis of retinal blood vessels plays an important role in detecting and treating retinal diseases. In this review, we present an automated method to segment blood vessels of fundus retinal image. The proposed method could be used to support a non-intrusive diagnosis in modern ophthalmology for early detection of retinal diseases, treatment evaluation or clinical study. This study combines the bias correction and an adaptive histogram equalisation to enhance the appearance of the blood vessels. Then the blood vessels are extracted using probabilistic modelling that is optimised by the expectation maximisation algorithm. The method is evaluated on fundus retinal images of STARE and DRIVE datasets. The experimental results are compared with some recently published methods of retinal blood vessels segmentation. The experimental results show that our method achieved the best overall performance and it is comparable to the performance of human experts.

  20. The progressive outer retinal necrosis syndrome.

    PubMed

    Holland, G N

    1994-01-01

    The progressive outer retinal necrosis (PORN) syndrome is a recently described clinical variant of necrotizing herpetic retinopathy in patients with the acquired immunodeficiency syndrome (AIDS). It is caused by varicellazoster virus infection of the retina. Its course and clinical features distinguish it from the acute retinal necrosis syndrome and CMV retinopathy. Early disease is characterized by multifocal deep retinal opacification. Lesions rapidly coalesce and progress to total retinal necrosis over a short period of time. Despite aggressive therapy with intravenous antivirial drugs, prognosis is poor; disease progression and/or recurrence is common, and the majority of patients develop no light perception vision. Total retinal detachments are common. Prophylaxis against retinal detachment using laser retinopexy has not been useful in most cases. PORN syndrome is an uncommon, but devastating complication of AIDS. PMID:7852023

  1. Retinal abnormalities in β-thalassemia major.

    PubMed

    Bhoiwala, Devang L; Dunaief, Joshua L

    2016-01-01

    Patients with beta (β)-thalassemia (β-TM: β-thalassemia major, β-TI: β-thalassemia intermedia) have a variety of complications that may affect all organs, including the eye. Ocular abnormalities include retinal pigment epithelial degeneration, angioid streaks, venous tortuosity, night blindness, visual field defects, decreased visual acuity, color vision abnormalities, and acute visual loss. Patients with β-thalassemia major are transfusion dependent and require iron chelation therapy to survive. Retinal degeneration may result from either retinal iron accumulation from transfusion-induced iron overload or retinal toxicity induced by iron chelation therapy. Some who were never treated with iron chelation therapy exhibited retinopathy, and others receiving iron chelation therapy had chelator-induced retinopathy. We will focus on retinal abnormalities present in individuals with β-thalassemia major viewed in light of new findings on the mechanisms and manifestations of retinal iron toxicity. PMID:26325202

  2. Role of retinal vascular endothelial cells in development of CMV retinitis.

    PubMed Central

    Rao, N A; Zhang, J; Ishimoto, S

    1998-01-01

    PURPOSE: Although cytomegalovirus (CMV) retinitis is known to occur in association with retinal microangiopathy in individuals with marked immunodeficiency, glial cells are believed to be the initial target cells in the development of retinitis. Moreover, it has been hypothesized that CMV gains access to the retinal glia because of altered vascular permeability. In an attempt to address the hypothesis, we studied 30 autopsy eyes of AIDS patients with systemic CMV infection, with or without clinically apparent CMV retinitis. METHODS: The autopsy eyes were processed in three ways. First, dual immunohistochemical studies were done by using anti-CMV antibodies for immediate early, early, and late antigens. The retinal cell types infected with the virus were then determined by using anti-GFAP, anti-VonWillebrand's factor, neuronal specific enolase, and leukocyte marker CD68. Second, selected eyes were processed for in situ hybridization with DNA probe specific to CMV. Third, an eye with clinically apparent CMV retinitis was submitted for electron microscopic examination. RESULTS: At the site of retinal necrosis in those eyes with a clinical diagnosis of CMV retinitis, the immunohistochemical, in situ hybridization, and ultrastructural examinations revealed that CMV was present primarily in the Müller cells and in perivascular glial cells. Adjacent to these infected cells, focal areas of positive staining for CMV antigen were seen in the glial cells, neuronal cells, and retinal pigment epithelial cells. At these sites most of the retinal capillaries were devoid of endothelial cells. Few vessels located at the advancing margin of retinal necrosis showed the presence of viral proteins in the endothelial cells. CONCLUSIONS: The present results indicate that retinal vascular endothelial cells could be the initial target in the development of viral retinitis, with subsequent spread of the infection to perivascular glia, Müller cells, and other retinal cells, including the

  3. Retinal vein occlusion: current treatment.

    PubMed

    Lattanzio, Rosangela; Torres Gimeno, Ana; Battaglia Parodi, Maurizio; Bandello, Francesco

    2011-01-01

    Retinal vein occlusion (RVO) is a pathology noted for more than 150 years. Although a lot has been written on the matter, it is still a frequent condition with multifactorial etiopathogenesis with many unclear aspects. The RVO pathogenesis has varied systemic and local implications that make it difficult to elaborate treatment guidelines. The management of the patient with RVO is very complex and a multidisciplinary approach is required in order to identify and correct the associated risk factors. Laser therapy remains the gold standard in RVO, but only modest functional improvement has been shown in branch retinal occlusion forms. Multicenter studies of intravitreal drugs present them as an option to combine with laser. Anti-vascular endothelial growth factor, corticosteroids and sustained-release implants are the future weapons to stop disease progression and get a better visual outcome. Consequently, it is useful to clarify some aspects of the pathology that allow a better patient management. PMID:20938213

  4. Retinal fibrosis in diabetic retinopathy.

    PubMed

    Roy, Sayon; Amin, Shruti; Roy, Sumon

    2016-01-01

    In response to injury, reparative processes are triggered to restore the damaged tissue; however, such processes are not always successful in rebuilding the original state. The formation of fibrous connective tissue is known as fibrosis, a hallmark of the reparative process. For fibrosis to be successful, delicately balanced cellular events involving cell proliferation, cell migration, and extracellular matrix (ECM) remodeling must occur in a highly orchestrated manner. While successful repair may result in a fibrous scar, this often restores structural stability and functionality to the injured tissue. However, depending on the functionality of the injured tissue, a fibrotic scar can have a devastating effect. For example, in the retina, fibrotic scarring may compromise vision and ultimately lead to blindness. In this review, we discuss some of the retinal fibrotic complications and highlight mechanisms underlying the development of retinal fibrosis in diabetic retinopathy.

  5. Gene Therapy for Retinal Diseases

    PubMed Central

    Samiy, Nasrollah

    2014-01-01

    Gene therapy has a growing research potential particularly in the field of ophthalmic and retinal diseases owing to three main characteristics of the eye; accessibility in terms of injections and surgical interventions, its immune-privileged status facilitating the accommodation to the antigenicity of a viral vector, and tight blood-ocular barriers which save other organs from unwanted contamination. Gene therapy has tremendous potential for different ocular diseases. In fact, the perspective of gene therapy in the field of eye research does not confine to exclusive monogenic ophthalmic problems and it has the potential to include gene based pharmacotherapies for non-monogenic problems such as age related macular disease and diabetic retinopathy. The present article has focused on how gene transfer into the eye has been developed and used to treat retinal disorders with no available therapy at present. PMID:25709778

  6. Retinal vein occlusion: current treatment.

    PubMed

    Lattanzio, Rosangela; Torres Gimeno, Ana; Battaglia Parodi, Maurizio; Bandello, Francesco

    2011-01-01

    Retinal vein occlusion (RVO) is a pathology noted for more than 150 years. Although a lot has been written on the matter, it is still a frequent condition with multifactorial etiopathogenesis with many unclear aspects. The RVO pathogenesis has varied systemic and local implications that make it difficult to elaborate treatment guidelines. The management of the patient with RVO is very complex and a multidisciplinary approach is required in order to identify and correct the associated risk factors. Laser therapy remains the gold standard in RVO, but only modest functional improvement has been shown in branch retinal occlusion forms. Multicenter studies of intravitreal drugs present them as an option to combine with laser. Anti-vascular endothelial growth factor, corticosteroids and sustained-release implants are the future weapons to stop disease progression and get a better visual outcome. Consequently, it is useful to clarify some aspects of the pathology that allow a better patient management.

  7. Retinitis pigmentosa in southern Africa.

    PubMed

    Greenberg, J; Bartmann, L; Ramesar, R; Beighton, P

    1993-11-01

    Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal disorders which are a common cause of genetic blindness. The relative frequencies of the different forms of RP in South Africa, as determined from the register at the DNA banking centre for RP at the Department of Human Genetics, University of Cape Town, are presented and discussed. Of the 125 families analysed, 29 (23%) showed autosomal dominant, 33 (27%) autosomal recessive and 3 (3%) X-linked inheritance. In 10 families the pedigree data were insufficient to allow accurate genetic subtyping and a further 50 patients were sporadic without a family history of RP or other syndromic features which would allow categorization. PMID:8313621

  8. Operational challenges of retinal prostheses.

    PubMed

    Schmid, Erich W; Fink, Wolfgang; Wilke, Robert

    2014-12-01

    Two computational models for research on retinal implants are presented. In the first model, the electric field produced by a multi-electrode array in a uniform retina is calculated. It is shown how cross talk of activated electrodes and the resulting bunching of field lines in monopole and dipole activation prevent high resolution imaging with retinal implants. Furthermore, it is demonstrated how sequential stimulation and multipolar stimulation may overcome this limitation. In the second model a target volume, i.e., a probe cylinder approximating a bipolar cell, in the retina is chosen, and the passive Heaviside cable equation is solved inside this target volume to calculate the depolarization of the cell membrane. The depolarization as a function of time indicates that shorter signals stimulate better as long as the current does not change sign during stimulation of the retina, i.e., mono-phasic stimulation. Both computational models are equally applicable to epiretinal, subretinal, and suprachoroidal vision implants. PMID:25443535

  9. Postadenoidectomy hemorrhage: how we do it?

    PubMed Central

    Demirbilek, Nevzat; Evren, Cenk; Altun, Uzay

    2015-01-01

    Aims: Conventionally, adenoidectomy has been performed using blind curettage. Postoperative hemorrhage is the most common complication of surgery. There is no specific management algorithm in the literature. In this study, we described an endoscopic approach in the management of postadenoidectomy hemorrhage. Material and methods: Between 1995 and 2014, 7946 patients undergoing adenoidectomy under general anesthesia in our clinic were retrospectively analyzed. All patients had a rest adenoid tissue located in the choanae. Endoscopic excision of the tissue was performed without using a post-nasal pack. Results: All patients (100%) had a rest adenoid tissue located in the choanae. Hemorrhage was completely discontinued with endoscopic excision of the hemorrhagic tissue. Conclusion: Based on our study findings, we conclude that an endoscopic approach should be applied in all postoperative patients with hemorrhage who are unresponsive to conservative treatment modalities. PMID:25932238

  10. Acquired retinal folds in the cat.

    PubMed

    MacMillan, A D

    1976-06-01

    Retinal folds were found in 5 cats. The apparent cause of the folding was varied: in 1 cat the folds appeared after a localized retinal detachment; in 2 cats the condition accompanied other intraocular abnormalities associated with feline infectious peritonitis; 1 cat had active keratitis, and the retinal changes were thought to have been injury related; and 1 cat, bilaterally affected, had chronic glomerulonephritis. PMID:945253

  11. Aberrant protein trafficking in retinal degenerations: The initial phase of retinal remodeling.

    PubMed

    Bales, Katie L; Gross, Alecia K

    2016-09-01

    Retinal trafficking proteins are involved in molecular assemblies that govern protein transport, orchestrate cellular events involved in cilia formation, regulate signal transduction, autophagy and endocytic trafficking, all of which if not properly controlled initiate retinal degeneration. Improper function and or trafficking of these proteins and molecular networks they are involved in cause a detrimental cascade of neural retinal remodeling due to cell death, resulting as devastating blinding diseases. A universal finding in retinal degenerative diseases is the profound detection of retinal remodeling, occurring as a phased modification of neural retinal function and structure, which begins at the molecular level. Retinal remodeling instigated by aberrant trafficking of proteins encompasses many forms of retinal degenerations, such as the diverse forms of retinitis pigmentosa (RP) and disorders that resemble RP through mutations in the rhodopsin gene, retinal ciliopathies, and some forms of glaucoma and age-related macular degeneration (AMD). As a large majority of genes associated with these different retinopathies are overlapping, it is imperative to understand their underlying molecular mechanisms. This review will discuss some of the most recent discoveries in vertebrate retinal remodeling and retinal degenerations caused by protein mistrafficking. PMID:26632497

  12. Retinal pathways influence temporal niche

    PubMed Central

    Doyle, Susan E.; Yoshikawa, Tomoko; Hillson, Holly; Menaker, Michael

    2008-01-01

    In mammals, light input from the retina entrains central circadian oscillators located in the suprachiasmatic nuclei (SCN). The phase of circadian activity rhythms with respect to the external light:dark cycle is reversed in diurnal and nocturnal species, although the phase of SCN rhythms relative to the light cycle remains unchanged. Neural mechanisms downstream from the SCN are therefore believed to determine diurnality or nocturnality. Here, we report a switch from nocturnal to diurnal entrainment of circadian activity rhythms in double-knockout mice lacking the inner-retinal photopigment melanopsin (OPN4) and RPE65, a key protein used in retinal chromophore recycling. These mice retained only a small amount of rod function. The change in entrainment phase of Rpe65−/−;Opn4−/− mice was accompanied by a reversal of the rhythm of clock gene expression in the SCN and a reversal in acute masking effects of both light and darkness on activity, suggesting that the nocturnal to diurnal switch is due to a change in the neural response to light upstream from the SCN. A switch from nocturnal to diurnal activity rhythms was also found in wild-type mice transferred from standard intensity light:dark cycles to light:dark cycles in which the intensity of the light phase was reduced to scotopic levels. These results reveal a novel mechanism by which changes in retinal input can mediate acute temporal-niche switching. PMID:18695249

  13. Multineuronal codes in retinal signaling.

    PubMed Central

    Meister, M

    1996-01-01

    The visual world is presented to the brain through patterns of action potentials in the population of optic nerve fibers. Single-neuron recordings show that each retinal ganglion cell has a spatially restricted receptive field, a limited integration time, and a characteristic spectral sensitivity. Collectively, these response properties define the visual message conveyed by that neuron's action potentials. Since the size of the optic nerve is strictly constrained, one expects the retina to generate a highly efficient representation of the visual scene. By contrast, the receptive fields of nearby ganglion cells often overlap, suggesting great redundancy among the retinal output signals. Recent multineuron recordings may help resolve this paradox. They reveal concerted firing patterns among ganglion cells, in which small groups of nearby neurons fire synchronously with delays of only a few milliseconds. As there are many more such firing patterns than ganglion cells, such a distributed code might allow the retina to compress a large number of distinct visual messages into a small number of optic nerve fibers. This paper will review the evidence for a distributed coding scheme in the retinal output. The performance limits of such codes are analyzed with simple examples, illustrating that they allow a powerful trade-off between spatial and temporal resolution. PMID:8570603

  14. Update on Pharmacologic Retinal Vascular Toxicity.

    PubMed

    Schwartz, Stephen G; Grzybowski, Andrzej; Wasinska-Borowiec, Weronika; Flynn, Harry W; Mieler, William F

    2015-01-01

    Several medications are associated with retinal vascular toxicity. These include intraocular aminoglycosides, oral contraceptives, interferon alpha, several other agents, and talc, which occurs as a vehicle in some oral medications that may be abused intravenously. As a group, these entities represent a small but clinically relevant category of retinal toxicity from medications. Some of the manifestations (e.g., retinal vascular occlusion) are nonspecific, but others are more specific, including clinically visible talc emboli in retinal vessels. Toxicity may be asymptomatic or may cause irreversible visual loss. By maintaining a high index of suspicion, the correct diagnosis can usually be made.

  15. Retinal Macroglial Responses in Health and Disease

    PubMed Central

    de Hoz, Rosa; Rojas, Blanca; Ramírez, Ana I.; Salazar, Juan J.; Gallego, Beatriz I.; Triviño, Alberto; Ramírez, José M.

    2016-01-01

    Due to their permanent and close proximity to neurons, glial cells perform essential tasks for the normal physiology of the retina. Astrocytes and Müller cells (retinal macroglia) provide physical support to neurons and supplement them with several metabolites and growth factors. Macroglia are involved in maintaining the homeostasis of extracellular ions and neurotransmitters, are essential for information processing in neural circuits, participate in retinal glucose metabolism and in removing metabolic waste products, regulate local blood flow, induce the blood-retinal barrier (BRB), play fundamental roles in local immune response, and protect neurons from oxidative damage. In response to polyetiological insults, glia cells react with a process called reactive gliosis, seeking to maintain retinal homeostasis. When malfunctioning, macroglial cells can become primary pathogenic elements. A reactive gliosis has been described in different retinal pathologies, including age-related macular degeneration (AMD), diabetes, glaucoma, retinal detachment, or retinitis pigmentosa. A better understanding of the dual, neuroprotective, or cytotoxic effect of macroglial involvement in retinal pathologies would help in treating the physiopathology of these diseases. The extensive participation of the macroglia in retinal diseases points to these cells as innovative targets for new drug therapies. PMID:27294114

  16. [Novel mechanism for retinal vascular diseases].

    PubMed

    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.

  17. Retinal detachment associated with atopic dermatitis.

    PubMed Central

    Takahashi, M; Suzuma, K; Inaba, I; Ogura, Y; Yoneda, K; Okamoto, H

    1996-01-01

    BACKGROUND: Retinal detachment associated with atopic dermatitis, one of the most common forms of dermatitis in Japan, has markedly increased in Japan in the past 10 years. To clarify pathogenic mechanisms of retinal detachment in such cases, we retrospectively studied clinical characteristics of retinal detachment associated with atopic dermatitis. METHODS: We examined the records of 80 patients (89 eyes) who had retinal detachment associated with atopic dermatitis. The patients were classified into three groups according to lens status: group A, eyes with clear lenses (40 eyes); group B, eyes with cataract (38 eyes), and group C, aphakic or pseudophakic eyes (11 eyes). RESULTS: No significant differences were noted in the ratio of males to females, age distribution, refractive error, or characteristic of retinal detachment among the three groups. The types of retinal breaks, however, were different in eyes with and without lens changes. While atrophic holes were dominant in group A, retinal dialysis was mainly seen in groups B and C. CONCLUSION: These findings suggested that anterior vitreoretinal traction may play an important role in the pathogenesis of retinal breaks in eyes with atopic cataract and that the same pathological process may affect the formation of cataract and tractional retinal breaks in patients with atopic dermatitis. PMID:8664234

  18. Retinal Cell Degeneration in Animal Models

    PubMed Central

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

    2016-01-01

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

  19. Update on Pharmacologic Retinal Vascular Toxicity.

    PubMed

    Schwartz, Stephen G; Grzybowski, Andrzej; Wasinska-Borowiec, Weronika; Flynn, Harry W; Mieler, William F

    2015-01-01

    Several medications are associated with retinal vascular toxicity. These include intraocular aminoglycosides, oral contraceptives, interferon alpha, several other agents, and talc, which occurs as a vehicle in some oral medications that may be abused intravenously. As a group, these entities represent a small but clinically relevant category of retinal toxicity from medications. Some of the manifestations (e.g., retinal vascular occlusion) are nonspecific, but others are more specific, including clinically visible talc emboli in retinal vessels. Toxicity may be asymptomatic or may cause irreversible visual loss. By maintaining a high index of suspicion, the correct diagnosis can usually be made. PMID:26350526

  20. Crewmembers in the middeck with the Retinal Photography experiment.

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Mission Pilot Robert Cabana conducting the Retinal Photography life sciences experiment on test subject Mission Specialist Michael Clifford. The Retinal Photography experiment is Detailed Supplementary Objective # 474.

  1. Imaging of Hereditary Hemorrhagic Telangiectasia

    SciTech Connect

    Carette, Marie-France Nedelcu, Cosmina; Tassart, Marc; Grange, Jean-Didier; Wislez, Marie; Khalil, Antoine

    2009-07-15

    This pictorial review is based on our experience of the follow-up of 120 patients at our multidisciplinary center for hereditary hemorrhagic telangiectasia (HHT). Rendu-Osler-Weber disease or HHT is a multiorgan autosomal dominant disorder with high penetrance, characterized by epistaxis, mucocutaneous telangiectasis, and visceral arteriovenous malformations (AVMs). The research on gene mutations is fundamental and family screening by clinical examination, chest X-ray, research of pulmonary shunting, and abdominal color Doppler sonography is absolutely necessary. The angioarchitecture of pulmonary AVMs can be studied by unenhanced multidetector computed tomography; however, all other explorations of liver, digestive bowels, or brain require administration of contrast media. Magnetic resonance angiography is helpful for central nervous system screening, in particular for the spinal cord, but also for pulmonary, hepatic, and pelvic AVMs. Knowledge of the multiorgan involvement of HHT, mechanism of complications, and radiologic findings is fundamental for the correct management of these patients.

  2. [Management of major postpartum hemorrhage].

    PubMed

    Nebout, Sophie; Merbai, Nadia; Faitot, Valentina; Keita, Hawa

    2014-02-01

    Postpartum hemorrhage (PPH) is defined by loss of greater than 500 mL of blood following vaginal delivery or 1,000 mL of blood following cesarean section, in the first 24 hours postpartum. Its incidence is up to 5% and the severe forms represent 1% of births. PPH is the first cause of obstetrical maternal mortality in France and 90% of these deaths are considered as preventable. Its management is multidisciplinary (obstetricians, anesthetists, midwives, biologists and interventional radiologists), based on treatment protocols where time is a major prognosis factor. In case of failure of the initial measures (oxytocin, manual placenta removal, uterus and birth canal examination), the management of severe forms includes active resuscitation (intravenous fluids, blood transfusion, vasoactive drugs), haemostatic interventions (sulprostone, tamponnade and haemostatic suture, surgical procedures and arterial embolization) and the correction of any potential coagulopathy (administration of blood products and haemostatic agents). PMID:24373716

  3. Congenital hemorrhagic disorders in Jordan.

    PubMed

    Awidi, A S

    1984-07-29

    The results of a three year prospective study of inherited bleeding syndromes in Jordan is presented. There were 112 patients from 64 families. Of these there were 42 patients with hemophilia A, 23 with Glanzmann's thrombasthenia, 22 with von Willebrand's disease, 11 with Christmas disease, 6 with hypofibrinogenemia, 3 with afibrinogenemia, 2 with factor XIII deficiency, 2 with storage pool disease and 1 with factor XI deficiency. The pattern of inherited bleeding syndromes in Jordan is different from that seen in Europe and U.S.A. in that Glanzmann's thrombasthenia is very common. High proportion of hemophiliacs were severe. Arthropathy was common. A significant number of bleeders had fatal hemorrhage. In a high proportion of patients, no family history of bleeding was found.

  4. Second harmonic generation from Langmuir-Blodgett films of retinal and retinal Schiff bases

    SciTech Connect

    Huang, J.; Lewis, A.; Rasing, T.

    1988-04-07

    The second harmonic signal from monolayers of retinal and retinal Schiff bases is reported. The results have yielded information on the monolayer structure and demonstrate that retinal and retinal Schiff bases have large second-order molecular hyperpolarizabilities with values of 1.4 x 10/sup -28/, 1.2 x 10/sup -28/, and 2.3 x 10/sup -28/ esu for retinal, the unprotonated Schiff base, and the protonated Schiff base, respectively. These values compare well with the known variation in the alteration in the dipole moment of such chromophores upon excitation.

  5. The bacterial toxin CNF1 as a tool to induce retinal degeneration reminiscent of retinitis pigmentosa

    PubMed Central

    Guadagni, Viviana; Cerri, Chiara; Piano, Ilaria; Novelli, Elena; Gargini, Claudia; Fiorentini, Carla; Caleo, Matteo; Strettoi, Enrica

    2016-01-01

    Retinitis pigmentosa (RP) comprises a group of inherited pathologies characterized by progressive photoreceptor degeneration. In rodent models of RP, expression of defective genes and retinal degeneration usually manifest during the first weeks of postnatal life, making it difficult to distinguish consequences of primary genetic defects from abnormalities in retinal development. Moreover, mouse eyes are small and not always adequate to test pharmacological and surgical treatments. An inducible paradigm of retinal degeneration potentially extensible to large animals is therefore desirable. Starting from the serendipitous observation that intraocular injections of a Rho GTPase activator, the bacterial toxin Cytotoxic Necrotizing Factor 1 (CNF1), lead to retinal degeneration, we implemented an inducible model recapitulating most of the key features of Retinitis Pigmentosa. The model also unmasks an intrinsic vulnerability of photoreceptors to the mechanism of CNF1 action, indicating still unexplored molecular pathways potentially leading to the death of these cells in inherited forms of retinal degeneration. PMID:27775019

  6. Retinal nerve fiber layer thickness and retinal vessel calibers in children with thalassemia minor

    PubMed Central

    Acer, Semra; Balcı, Yasemin I; Pekel, Gökhan; Ongun, Tuğba T; Polat, Aziz; Çetin, Ebru N; Yağcı, Ramazan

    2016-01-01

    Objectives: Evaluation of the peripapillary retinal nerve fiber layer thickness, subfoveal choroidal thickness, and retinal vessel caliber measurements in children with thalassemia minor. Methods: In this cross-sectional and comparative study, 30 thalassemia minor patients and 36 controls were included. Heidelberg spectral domain optical coherence tomography was used for peripapillary retinal nerve fiber layer thickness, subfoveal choroidal thickness, and retinal vessel caliber measurements. Results: There was no statistically significant difference in retinal nerve fiber layer thickness and subfoveal choroidal thickness between the two groups (p > 0.05). There was no correlation between retinal nerve fiber layer thickness and hemoglobin values. Both the arterioral and venular calibers were higher in thalassemia minor group (p < 0.05). Conclusion: There is increased retinal arterioral and venular calibers in children with thalassemia minor compared with controls. PMID:27540484

  7. Remote cerebellar hemorrhage following supratentorial cerebrovascular surgery.

    PubMed

    Smith, Ross; Kebriaei, Meysam; Gard, Andrew; Thorell, William; Surdell, Daniel

    2014-04-01

    Three patients with remote cerebellar hemorrhage following supratentorial cerebrovascular surgery are presented. Remote cerebellar hemorrhage is a rare surgical complication that is most often associated with aneurysm clipping or temporal lobectomies. Bleeding occurs on the superior cerebellar cortex and is believed to be venous in origin. The precise pathogenesis of remote cerebellar hemorrhage has yet to be fully elucidated but is generally considered to be a consequence of intraoperative cerebrospinal fluid loss causing caudal displacement of the cerebellum with resultant stretching of the supracerebellar veins. This case series will hopefully shed further light on the incidence, presentation, workup, and treatment of this particular complication of supratentorial surgery. PMID:24238635

  8. Fundus autofluorescence applications in retinal imaging

    PubMed Central

    Gabai, Andrea; Veritti, Daniele; Lanzetta, Paolo

    2015-01-01

    Fundus autofluorescence (FAF) is a relatively new imaging technique that can be used to study retinal diseases. It provides information on retinal metabolism and health. Several different pathologies can be detected. Peculiar AF alterations can help the clinician to monitor disease progression and to better understand its pathogenesis. In the present article, we review FAF principles and clinical applications. PMID:26139802

  9. Argus II retinal prosthesis system: An update.

    PubMed

    Rachitskaya, Aleksandra V; Yuan, Alex

    2016-09-01

    This review focuses on a description of the Argus II retinal prosthesis system (Argus II; Second Sight Medical Products, Sylmar, CA) that was approved for humanitarian use by the FDA in 2013 in patients with retinitis pigmentosa with bare or no light perception vision. The article describes the components of Argus II, the studies on the implant, and future directions. PMID:26855177

  10. The optic nerve sheath hemorrhage is a non-specific finding in cases of suspected child abuse.

    PubMed

    Leeuw, Marc De; Beuls, Emile; Jorens, Philippe G; Parizel, Paul; Jacobs, Werner

    2015-11-01

    In young infants, the triad consisting of acute encephalopathy, retinal hemorrhages, and a subdural hematoma is a nonspecific finding. It has traumatic and non-traumatic etiologies. The triad may be found among a vast spectrum of natural diseases. Optic nerve sheath hemorrhage in infants is typically detected at autopsy. It is a nonspecific finding that can be found in traumatic and non-traumatic etiologies. Neither the triad nor the ONSH are pathognomonic for an abusive head injury. Opposite to the triad, the spectrum of non-traumatic etiologies of ONSH is limited. In infants ONSH rarely occurs in spontaneous subarachnoidal hemorrhage or in infectious conditions. Our results show that the clinical significance of the optic nerve sheath hemorrhage in the forensic work-up of fatal cases of alleged abusive head injury is its limited differential diagnosis. Only after careful differential diagnosis ONSH may contribute to the diagnosis of AHT. However, the main limitation of our study is the sampling bias, as the eyes are usually removed when abusive head trauma is suspected. PMID:26386200

  11. Radial optic neurotomy in treating central retinal vein occlusion: a Meta-analysis

    PubMed Central

    Chen, Zhen-Na; Shao, Yan; Li, Xiao-Rong

    2016-01-01

    AIM To assess the feasibility of radial optic neurotomy (RON) in central retinal vein occlusion (CRVO) treatment with a Meta-analysis. METHODS Electronic databases were searched for comprehensive articles that compared efficacy of RON with that of other treatments in CRVO. Study quality was assessed and risk ratio (RR) and 95% confidence interval (CI) with fix- or random-effects model were calculated according to the heterogeneity. RESULTS A total of 200 eyes from 5 studies were included. The results indicated that no significant differences were found between groups with and without RON in improvement of visual acuity (VA) at 6mo follow-up (pooled RR 0.51, 95%CI 0.22 to 1.18, P=0.117) while improvement of VA showed significantly favourable in patients receiving RON treatment at 12mo follow-up (pooled RR 2.27, 95%CI 1.31 to 3.95, P=0.004). For complications, RON treatment was more effective in reducing neovascular glaucoma (pooled RR 0.45, 95%CI 0.21 to 0.97, P=0.042) but was comparable in retinal detachment (pooled RR 2.41, 95%CI 0.51 to 11.39, P=0.267) and vitreous hemorrhage (pooled RR 0.91, 95%CI 0.33 to 2.46, P=0.847). CONCLUSION Compared with some certain treatment modalities, RON might offer better VA at 12mo and decrease the rate of neovascular glaucoma without changing the rate of retinal detachment and vitreous hemorrhage. Further studies are required considering the limitation of the research. PMID:27366695

  12. Serous retinal detachment following panretinal photocoagulation (PRP) using Pattern Scan Laser (PASCAL) photocoagulator

    PubMed Central

    Azar, Georges; Wolff, Benjamin; Cornut, Pierre-Loïc; Mauget-Faÿsse, Martine

    2012-01-01

    Objective: To report a case of serous retinal detachment after Pattern Scan Laser (PASCAL) treatment in a diabetic woman. Methods: A 34-year-old diabetic woman presented with florid diabetic retinopathy after a miscarriage during the 20th week of pregnancy. Her Best Corrected Visual Acuity (BCVA) was 20/40 right eye (OD) and 20/30 left eye (OS). Fundus exam showed multiple microaneurysms, large blot hemorrhages and venous dilation both eyes (OU). Fundus fluorescein angiography (FFA) revealed large areas of capillary nonperfusion and panretinal neovascularisation in all quadrants OU. Macular Spectral-Domain Optical Coherence Tomography scan (SD-OCT) did not show any foveal thickening. Panretinal photocoagulation (PRP) was immediately performed OU during the same day. Results: Two days after PASCAL treatment, her BCVA decreased to 20/80 OU and worsened to Count Fingers (CF) during the following days. Fundus exam revealed an extensive serous retinal detachment confirmed on SD-OCT. 2 sub-conjunctival injections of 0.1 ml Betamethasone were done OU. One month later, BCVA improved to 20/30 and SD-OCT confirmed regression of retinal detachment. Conclusions: PASCAL is considered to be a safe treatment, but one has to be aware of its potential side effects. It has to be used with caution in pregnant women.

  13. Retinal artery occlusions in children.

    PubMed

    Dharmasena, Aruna; Wallis, Simon

    2014-01-01

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

  14. The cell stress machinery and retinal degeneration.

    PubMed

    Athanasiou, Dimitra; Aguilà, Monica; Bevilacqua, Dalila; Novoselov, Sergey S; Parfitt, David A; Cheetham, Michael E

    2013-06-27

    Retinal degenerations are a group of clinically and genetically heterogeneous disorders characterised by progressive loss of vision due to neurodegeneration. The retina is a highly specialised tissue with a unique architecture and maintaining homeostasis in all the different retinal cell types is crucial for healthy vision. The retina can be exposed to a variety of environmental insults and stress, including light-induced damage, oxidative stress and inherited mutations that can lead to protein misfolding. Within retinal cells there are different mechanisms to cope with disturbances in proteostasis, such as the heat shock response, the unfolded protein response and autophagy. In this review, we discuss the multiple responses of the retina to different types of stress involved in retinal degenerations, such as retinitis pigmentosa, age-related macular degeneration and glaucoma. Understanding the mechanisms that maintain and re-establish proteostasis in the retina is important for developing new therapeutic approaches to fight blindness. PMID:23684651

  15. Defective retinal vascular endothelial cell development as a consequence of impaired integrin αVβ8-mediated activation of transforming growth factor-β.

    PubMed

    Arnold, Thomas D; Ferrero, Gina M; Qiu, Haiyan; Phan, Isabella T; Akhurst, Rosemary J; Huang, Eric J; Reichardt, Louis F

    2012-01-25

    Deletions of the genes encoding the integrin αVβ8 (Itgav, Itgb8) have been shown to result in abnormal vascular development in the CNS, including prenatal and perinatal hemorrhage. Other work has indicated that a major function of this integrin in vivo is to promote TGFβ activation. In this paper, we show that Itgb8 mRNA is strongly expressed in murine Müller glia and retinal ganglion cells, but not astrocytes. We further show that Itgb8 deletion in the entire retina severely perturbs development of the murine retinal vasculature, elevating vascular branch point density and vascular coverage in the superficial vascular plexus, while severely impairing formation of the deep vascular plexus. The stability of the mutant vasculature is also impaired as assessed by the presence of hemorrhage and vascular basal lamina sleeves lacking endothelial cells. Specific deletion of Itgb8 in Müller glia and neurons, but not deletion in astrocytes, recapitulates the phenotype observed following Itgb8 in the entire retina. Consistent with αVβ8's role in TGFβ1 activation, we show that retinal deletion of Tgfb1 results in very similar retinal vascular abnormalities. The vascular deficits appear to reflect impaired TGFβ signaling in vascular endothelial cells because retinal deletion of Itgb8 reduces phospho-SMAD3 in endothelial cells and endothelial cell-specific deletion of the TGFβRII gene recapitulates the major deficits observed in the Itgb8 and TGFβ1 mutants. Of special interest, the retinal vascular phenotypes observed in each mutant are remarkably similar to those of others following inhibition of neuropilin-1, a receptor previously implicated in TGFβ activation and signaling.

  16. Primary Reactions in Retinal Proteins

    NASA Astrophysics Data System (ADS)

    Diller, R.

    Conversion of sunlight into energy or information and their storage on a chemical level is essential for life on earth. An important family of chromoproteins performing these tasks is that of retinal binding proteins. Prominent examples are rhodopsin (Rh) [1,2] as the visual pigment in vertebrate and invertebrate animals, the archaeal rhodopsins bacteriorhodopsin (BR) [3] as a light driven proton pump, halorhodopsin (HR) [4,5] as a light driven chloride pump, sensory rhodopsin I and II (SRI, SRII) [6] as photoreceptors, and proteorhodopsin (PR) [7] as another bacterial proton pump.

  17. Metastatic renal cell carcinoma: the first report of unilateral fundus hemorrhage induced by sorafenib

    PubMed Central

    Yao, Kai; Liu, Zhuo Wei; Pan, Wen Tao; Ye, Yun Lin; Yang, Ping; Huang, Yi Chuan; Wu, Zhi Ming; Zhou, Fang Jian

    2016-01-01

    Background Renal cell carcinoma (RCC) is the most common type of kidney tumor with increasing incidence. Tyrosine Kinase Inhibitors (TKIs) are considered important treatment in the management of metastatic RCC. Some previous studies demonstrated that sorafenib treatment is associated with a significantly increased risk of potentially life-threatening adverse events, like bleeding. But bleeding at the fundus site is the rarest type of hemorrhage. As for TKIs' risk of bleeding, how we distinguish the degree of bleeding and what optimal strategies should we take to manage bleeding, needs to be studied systematically. Results With a long-term exposure (17 months) to sorafenib, he experienced blurred vision in his right eye and was hospitalized. The patient's diagnosis was central retinal vein occlusion (CRVO) of the right eye. Unfortunately sorafenib was terminated. Materials and Methods The authors describe the first case of unilateral fundus hemorrhage induced by sorafenib. A 42-year-old man was diagnosed metastatic left RCC, with clinical stage and prognostic risk being assessed as T4N1M1 and intermediate. He received a radical left nephrectomy and retroperitoneal lymph node dissection, with taking the oral multi-targeted TKI, sorafenib (800 mg daily) from 7 months to 7 days before the surgery and 7 days after the surgery restarting again until the occurrence of fundus hemorrhage. Conclusions In this patient, long-term exposure to sorafenib possibly has increased the risk of fundus hemorrhage. This article provides us a previously undescribed morbidity associated with sorafenib, which reminds us of understanding the risk of bleeding and how this complication might be managed systematically. PMID:27174916

  18. Spontaneous subarachnoid hemorrhage and glucose management.

    PubMed

    Schmutzhard, Erich; Rabinstein, Alejandro A

    2011-09-01

    Although metabolic abnormalities have been linked with poor outcome after subarachnoid hemorrhage, there are limited data addressing the impact of glycemic control or benefits of glucose management after aneurysmal subarachnoid hemorrhage. A systematic literature search was conducted of English-language articles describing original research on glycemic control in patients with subarachnoid hemorrhage. Case reports and case series were excluded. A total of 22 publications were selected for this review. Among the 17 studies investigating glucose as an outcome predictor, glucose levels during hospitalization were more likely to predict outcome than admission glucose. In general, hyperglycemia was linked to worse outcome. While insulin therapy in subarachnoid hemorrhage patients was shown to effectively control plasma glucose levels, plasma glucose control was not necessarily reflective of cerebral glucose such that very tight glucose control may lead to neuroglycopenia. Furthermore, tight glycemic control was associated with an increased risk for hypoglycemia which was linked to worse outcome. PMID:21850563

  19. Delayed Intracerebral Hemorrhage Secondary to Ventriculoperitoneal Shunt

    PubMed Central

    Ma, Li; Chen, Yi-Li; Yang, Shu-Xu; Wang, Yi-Rong

    2015-01-01

    Abstract The ventriculoperitoneal (VP) shunt is a routine procedure for cerebrospinal fluid (CSF) diversion, and is associated with many complications. A delayed hemorrhage after the VP shunt surgery, however, is quite rare. In this study, we report a case involving late-onset hemorrhage. The 67-year-old male patient with a history of head trauma and brain surgery underwent a VP shunt placement for hydrocephalus. The surgery course was uneventful and no bleeding was revealed in the first computed tomographic (CT) scan after the procedure. However, a massive intraparenchymal and intraventricular hemorrhage occurred 8 h following adjustment of the valve system on the 8th day after surgery. Erosion of the vasculature by catheter cannulation and a sudden reduction of CSF pressure after downregulation of the valve could be one of the possible causes of the intracerebral hemorrhage (ICH). PMID:26632700

  20. Splenic Involvement in Hereditary Hemorrhagic Telangiectasia

    PubMed Central

    Sato, Kota; Kato, Shunsuke; Nagano, Hiroto; Ohtsukasa, Shunro; Kawachi, Yasuyuki

    2016-01-01

    A 33-year-old man who presented with prolonged epigastric pain was referred to our hospital. He had experienced recurrent epistaxis and had a family history of hereditary hemorrhagic telangiectasia. Computed tomography and magnetic resonance imaging revealed splenomegaly and a 9 cm hypervascular mass in his spleen. Computed tomography also showed a pulmonary arteriovenous malformation and heterogeneous enhancement of the liver parenchyma, suggesting the presence of arteriosystemic shunts and telangiectases. Based on these findings, the patient was definitely diagnosed with hereditary hemorrhagic telangiectasia according to Curaçao criteria. He underwent splenectomy, and his symptoms disappeared after surgery. Pathological examination of the resected specimen revealed that the hypervascular lesion of the spleen was not a tumor but was composed of abnormal vessels associated with hereditary hemorrhagic telangiectasia. Symptomatic splenic involvement may be a rare manifestation of hereditary hemorrhagic telangiectasia but can be revealed by imaging modalities. PMID:27807449

  1. Epizootic hemorrhagic disease in yaks (Bos grunniens).

    PubMed

    Van Campen, Hana; Davis, Charlie; Flinchum, John D; Bishop, Jeanette V; Schiebel, Anita; Duncan, Colleen; Spraker, Terry

    2013-05-01

    An epizootic of hemorrhagic disease associated with Epizootic hemorrhagic disease virus serotype 2 (EHDV-2) infections in yaks from 5 herds occurred in Colorado between August 21 and October 3, 2012. Affected yaks presented with fever, lethargy, anorexia, dyspnea, and swollen conjunctivae. Ulcerated dental pads, mucoid sanguineous nasal discharge, petechial hemorrhages in multiple organs, pulmonary edema, and serosanguinous fluid in the thorax, abdomen, and pericardial sac were observed at necropsy. Blood and tissue samples from 8 yaks with similar clinical signs and necropsy findings were positive for EHDV-2 by reverse transcription polymerase chain reaction and 5 yaks were seropositive for EHDV. Tests for malignant catarrhal fever (Ovine herpesvirus 2), Bovine viral diarrhea virus, Bovine herpesvirus 1, Foot-and-mouth disease virus, and Vesicular stomatitis virus were negative. The findings indicate that yaks are susceptible to infection with EHDV-2 and exhibit the clinical signs, and gross and histologic lesions of hemorrhagic disease observed in other ruminant species. PMID:23572453

  2. Peribulbar anesthesia causing bilateral orbital hemorrhage

    PubMed Central

    Garft, Kyla; Burt, Peter; Burt, Benjamin

    2016-01-01

    We report a case of bilateral orbital hemorrhage as a complication of peribulbar anesthesia in a 78 year old man. Initially, unilateral orbital hemorrhage occurred but quickly spread to the contralateral side. Neuroophthalmological assessment revealed a proptosed tense globe with normal retinovascular findings. Visual acuity was adversely affected and this was conservatively managed with no lasting ophthalmic sequela. This patient’s case was reported as it illustrates an unusual complication of bilateral spread of orbital hemorrhage secondary to peribulbar anesthesia. It highlights how early ophthalmic assessment can ensure a good visual outcome in the setting of appropriate ophthalmic monitoring. The mechanisms of orbital hemorrhage spread and appropriate management options are discussed. PMID:27013899

  3. Predicting Hemorrhagic Transformation of Acute Ischemic Stroke

    PubMed Central

    Marsh, Elisabeth B.; Llinas, Rafael H.; Schneider, Andrea L.C.; Hillis, Argye E.; Lawrence, Erin; Dziedzic, Peter; Gottesman, Rebecca F.

    2016-01-01

    Abstract Hemorrhagic transformation (HT) increases the morbidity and mortality of ischemic stroke. Anticoagulation is often indicated in patients with atrial fibrillation, low ejection fraction, or mechanical valves who are hospitalized with acute stroke, but increases the risk of HT. Risk quantification would be useful. Prior studies have investigated risk of systemic hemorrhage in anticoagulated patients, but none looked specifically at HT. In our previously published work, age, infarct volume, and estimated glomerular filtration rate (eGFR) significantly predicted HT. We created the hemorrhage risk stratification (HeRS) score based on regression coefficients in multivariable modeling and now determine its validity in a prospectively followed inpatient cohort. A total of 241 consecutive patients presenting to 2 academic stroke centers with acute ischemic stroke and an indication for anticoagulation over a 2.75-year period were included. Neuroimaging was evaluated for infarct volume and HT. Hemorrhages were classified as symptomatic versus asymptomatic, and by severity. HeRS scores were calculated for each patient and compared to actual hemorrhage status using receiver operating curve analysis. Area under the curve (AUC) comparing predicted odds of hemorrhage (HeRS score) to actual hemorrhage status was 0.701. Serum glucose (P < 0.001), white blood cell count (P < 0.001), and warfarin use prior to admission (P = 0.002) were also associated with HT in the validation cohort. With these variables, AUC improved to 0.854. Anticoagulation did not significantly increase HT; but with higher intensity anticoagulation, hemorrhages were more likely to be symptomatic and more severe. The HeRS score is a valid predictor of HT in patients with ischemic stroke and indication for anticoagulation. PMID:26765425

  4. Pulmonary hemorrhage resulting from roller coaster.

    PubMed

    Yin, Ming; Tian, Qing; Shen, Hong

    2011-03-01

    Roller coasters are probably one of the more popular rides at amusement parks around the world, and there are few reported injuries. We report a case of symmetric diffuse upper lobe hemorrhage resulting from roller coaster in a previously healthy woman. The clinical course, management, and etiology of her case are discussed; and the literature is reviewed. To our knowledge, pulmonary hemorrhage in this setting has not yet been described. PMID:20825914

  5. Hemorrhagic sarcoid pleural effusion: A rare entity

    PubMed Central

    Jha, Onkar; Nair, Vidya; Talwar, Deepak

    2016-01-01

    Involvement of pleura by sarcoidosis remains a rare manifestation and varies from pleural effusion, pneumothorax, pleural thickening, hydropneumothorax, trapped lung, hemothorax, or chylothorax. Sarcoid pleural effusions presenting as hemorrhagic effusions are even more rare. We report a case of active pulmonary sarcoidosis presenting as hemorrhagic pleural effusion requiring tissue diagnosis to rule out malignancy. The rarity of the presentation prompted us to report this case. PMID:27625449

  6. Hemorrhagic sarcoid pleural effusion: A rare entity

    PubMed Central

    Jha, Onkar; Nair, Vidya; Talwar, Deepak

    2016-01-01

    Involvement of pleura by sarcoidosis remains a rare manifestation and varies from pleural effusion, pneumothorax, pleural thickening, hydropneumothorax, trapped lung, hemothorax, or chylothorax. Sarcoid pleural effusions presenting as hemorrhagic effusions are even more rare. We report a case of active pulmonary sarcoidosis presenting as hemorrhagic pleural effusion requiring tissue diagnosis to rule out malignancy. The rarity of the presentation prompted us to report this case.

  7. Argentine hemorrhagic fever: a primate model.

    PubMed

    Weissenbacher, M C; Calello, M A; Colillas, O J; Rondinone, S N; Frigerio, M J

    1979-01-01

    Experimental Junin virus infection of a New World primate, Callithrix jacchus, was evaluated. The virus produced anorexia, loss of weight, thrombocytopenia, leukopenia, and hemorrhagic and neurological symptoms and terminated in death. Virus was recovered from urine, blood samples and all tissues taken at autopsy. These preliminary observations show that several aspects of the experimental disease in C. jacchus are quite similar to severe natural Argentine hemorrhagic fever of man.

  8. Hemorrhagic sarcoid pleural effusion: A rare entity.

    PubMed

    Jha, Onkar; Nair, Vidya; Talwar, Deepak

    2016-01-01

    Involvement of pleura by sarcoidosis remains a rare manifestation and varies from pleural effusion, pneumothorax, pleural thickening, hydropneumothorax, trapped lung, hemothorax, or chylothorax. Sarcoid pleural effusions presenting as hemorrhagic effusions are even more rare. We report a case of active pulmonary sarcoidosis presenting as hemorrhagic pleural effusion requiring tissue diagnosis to rule out malignancy. The rarity of the presentation prompted us to report this case. PMID:27625449

  9. Cell Therapy Applications for Retinal Vascular Diseases: Diabetic Retinopathy and Retinal Vein Occlusion.

    PubMed

    Park, Susanna S

    2016-04-01

    Retinal vascular conditions, such as diabetic retinopathy and retinal vein occlusion, remain leading causes of vision loss. No therapy exists to restore vision loss resulting from retinal ischemia and associated retinal degeneration. Tissue regeneration is possible with cell therapy. The goal would be to restore or replace the damaged retinal vasculature and the retinal neurons that are damaged and/or degenerating from the hypoxic insult. Currently, various adult cell therapies have been explored as potential treatment. They include mesenchymal stem cells, vascular precursor cells (i.e., CD34+ cells, hematopoietic cells or endothelial progenitor cells), and adipose stromal cells. Preclinical studies show that all these cells have a paracrine trophic effect on damaged ischemic tissue, leading to tissue preservation. Endothelial progenitor cells and adipose stromal cells integrate into the damaged retinal vascular wall in preclinical models of diabetic retinopathy and ischemia-reperfusion injury. Mesenchymal stem cells do not integrate as readily but appear to have a primary paracrine trophic effect. Early phase clinical trials have been initiated and ongoing using mesenchymal stem cells or autologous bone marrow CD34+ cells injected intravitreally as potential therapy for diabetic retinopathy or retinal vein occlusion. Adipose stromal cells or pluripotent stem cells differentiated into endothelial colony-forming cells have been explored in preclinical studies and show promise as possible therapies for retinal vascular disorders. The relative safety or efficacy of these various cell therapies for treating retinal vascular disorders have yet to be determined.

  10. Occult hemorrhage in children with severe ITP.

    PubMed

    Flores, Adolfo; Buchanan, George R

    2016-03-01

    Little is known about the frequency and significance of clinically unapparent or occult hemorrhage in ITP. Therefore, we prospectively explored the sites and frequency of occult bleeding in children with severe ITP at diagnosis or upon symptomatic relapse in a prospective, single-institution cohort study of patients ≤ 18 years of age and a platelet count ≤ 10,000/mm(3) . Data collected included bleeding severity assessment, urinalysis, fecal occult blood testing, and non-contrast brain MRI. Stool and urine samples were tested within 7 days of diagnosis or symptomatic relapse. Three months after diagnosis or relapse a noncontrast brain MRI evaluated hemosiderin deposits resulting from prior localized hemorrhage. Fifty-two ITP patients were enrolled with a mean platelet count of 4,000/mm(3) . A significant occurrence of occult hemorrhage was identified in the urine (27%) compared with clinically overt hematuria (0.91%, P < 0.0005). CNS microbleeding in the superficial cortex of the left frontal lobe was identified in one child with occult bleeding in the urinary tract. There was no relationship between occult hemorrhage and bleeding manifestations on physical examination. Occult hemorrhage was not a harbinger of subsequent bleeding. Our findings suggest that occult hemorrhage occurs with greater frequency than overt bleeding in children with severe ITP. CNS microbleeding is a potential risk in this patient population. Assessment of brain microbleeds and microscopic hematuria in this patient population require additional study.

  11. Congenital hepatic cyst with intracystic hemorrhage

    PubMed Central

    Ni, Qingqiang; Zhang, Minfeng; Yang, Cheng; Cai, Wenchang; Zhao, Qian; Shen, Weifeng; Yang, Jiamei

    2016-01-01

    Abstract Introduction: Fast-growing congenital hepatic cysts with intracystic hemorrhage are rare in clinical practice. Additionally, the clinical manifestations of and laboratory and imaging findings for this condition are often nonspecific and are particularly difficult to differentiate from those of hepatobiliary cystadenoma and cystadenocarcinoma, thus posing great challenges for diagnosis and treatment. The 2 case reports presented here aim to analyze the diagnosis and treatment of 2 rare cases of congenital hepatic cysts with intracystic hemorrhage in the Chinese Han population to provide an important reference for the clinical diagnosis and treatment of this condition. Diagnoses: These 2 case reports present 2 rare cases of congenital hepatic cysts with intracystic hemorrhage. Case 1 involved a 31-year-old patient with a very large, fast-growing hepatic cyst with intracystic hemorrhage and elevated carbohydrate antigen 199. Case 2 involved a patient with intense, paroxysmal right upper abdominal pain; computed tomography suggested a hepatic cyst with intracystic hemorrhage and possibly hepatobiliary cystadenoma. Outcomes: Both patients underwent liver resection. Postoperative follow-up showed that for both patients, the symptoms improved, the laboratory findings returned to normal levels, and the surgical outcomes were satisfactory. Conclusion: Liver resection is an ideal treatment for patients with congenital hepatic cysts with intracystic hemorrhage, and especially those with fast-growing, symptomatic hepatic cysts or hepatic cysts that are difficult to differentiate from hepatobiliary cystadenoma and cystadenocarcinoma. PMID:27759646

  12. Impaired Fracture Healing after Hemorrhagic Shock

    PubMed Central

    Kobbe, Philipp; Pfeifer, Roman; Campbell, Graeme C.; Tohidnezhad, Mersedeh; Bergmann, Christian; Kadyrov, Mamed; Fischer, Horst; Glüer, Christian C.; Pape, Hans-Christoph; Pufe, Thomas

    2015-01-01

    Impaired fracture healing can occur in severely injured patients with hemorrhagic shock due to decreased soft tissue perfusion after trauma. We investigated the effects of fracture healing in a standardized pressure controlled hemorrhagic shock model in mice, to test the hypothesis that bleeding is relevant in the bone healing response. Male C57/BL6 mice were subjected to a closed femoral shaft fracture stabilized by intramedullary nailing. One group was additionally subjected to pressure controlled hemorrhagic shock (HS, mean arterial pressure (MAP) of 35 mmHg for 90 minutes). Serum cytokines (IL-6, KC, MCP-1, and TNF-α) were analyzed 6 hours after shock. Fracture healing was assessed 21 days after fracture. Hemorrhagic shock is associated with a significant increase in serum inflammatory cytokines in the early phase. Histologic analysis demonstrated a significantly decreased number of osteoclasts, a decrease in bone quality, and more cartilage islands after hemorrhagic shock. μCT analysis showed a trend towards decreased bone tissue mineral density in the HS group. Mechanical testing revealed no difference in tensile failure. Our results suggest a delay in fracture healing after hemorrhagic shock. This may be due to significantly diminished osteoclast recruitment. The exact mechanisms should be studied further, particularly during earlier stages of fracture healing. PMID:26106256

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

    PubMed

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

    2015-10-01

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

  14. Thrombin stimulates IL-6 and IL-8 expression in cytomegalovirus-infected human retinal pigment epithelial cells.

    PubMed

    Scholz, Martin; Vogel, Jens-Uwe; Höver, Gerold; Kotchetkov, Ruslan; Cinatl, Jaroslav; Doerr, Hans Wilhelm; Cinatl, Jindrich

    2004-02-01

    Recently, we reported that thrombin specifically stimulates protease-activated receptor-1 (PAR-1) signaling in RPE entailing inhibition of Sp1 dependent HCMV replication. We now studied whether thrombin modulates the expression of the proinflammatory cytokine/chemokines IL-6 and IL-8 in mock- and cytomegalovirus-infected human retinal pigment epithelial cells (RPE). Our data show that thrombin/PAR-1 stimulates IL-6 and IL-8 gene transcription and protein secretion in both mock- and HCMV-infected RPE. Thrombin/PAR-1-mediated signaling stimulated PKC and NF-kappaB-dependent IL-6 and IL-8 gene expression via phosphoinositide 3-kinase and further downstream via p42/44 and p38 MAPKs. Thus, thrombin/PAR-1-mediated IL-6/IL-8 gene expression is uncoupled from Sp1 inhibition and may support proinflammatory pathomechanisms probably involved in hemorrhage/HCMV retinitis progression.

  15. Genetic networks controlling retinal injury

    PubMed Central

    Vazquez-Chona, Felix R.; Khan, Amna N.; Chan, Chun K.; Moore, Anthony N.; Dash, Pramod K.; Hernandez, M. Rosario; Lu, Lu; Chesler, Elissa J.; Manly, Kenneth F.; Williams, Robert W.; Geisert, Eldon E.

    2010-01-01

    Purpose The present study defines genomic loci underlying coordinate changes in gene expression following retinal injury. Methods A group of acute phase genes expressed in diverse nervous system tissues was defined by combining microarray results from injury studies from rat retina, brain, and spinal cord. Genomic loci regulating the brain expression of acute phase genes were identified using a panel of BXD recombinant inbred (RI) mouse strains. Candidate upstream regulators within a locus were defined using single nucleotide polymorphism databases and promoter motif databases. Results The acute phase response of rat retina, brain, and spinal cord was dominated by transcription factors. Three genomic loci control transcript expression of acute phase genes in brains of BXD RI mouse strains. One locus was identified on chromosome 12 and was highly correlated with the expression of classic acute phase genes. Within the locus we identified the inhibitor of DNA binding 2 (Id2) as a candidate upstream regulator. Id2 was upregulated as an acute phase transcript in injury models of rat retina, brain, and spinal cord. Conclusions We defined a group of transcriptional changes associated with the retinal acute injury response. Using genetic linkage analysis of natural transcript variation, we identified regulatory loci and candidate regulators that control transcript levels of acute phase genes. PMID:16288200

  16. Fixation strategies for retinal immunohistochemistry.

    PubMed

    Stradleigh, Tyler W; Ishida, Andrew T

    2015-09-01

    Immunohistochemical and ex vivo anatomical studies have provided many glimpses of the variety, distribution, and signaling components of vertebrate retinal neurons. The beauty of numerous images published to date, and the qualitative and quantitative information they provide, indicate that these approaches are fundamentally useful. However, obtaining these images entailed tissue handling and exposure to chemical solutions that differ from normal extracellular fluid in composition, temperature, and osmolarity. Because the differences are large enough to alter intercellular and intracellular signaling in neurons, and because retinae are susceptible to crush, shear, and fray, it is natural to wonder if immunohistochemical and anatomical methods disturb or damage the cells they are designed to examine. Tissue fixation is typically incorporated to guard against this damage and is therefore critically important to the quality and significance of the harvested data. Here, we describe mechanisms of fixation; advantages and disadvantages of using formaldehyde and glutaraldehyde as fixatives during immunohistochemistry; and modifications of widely used protocols that have recently been found to improve cell shape preservation and immunostaining patterns, especially in proximal retinal neurons. PMID:25892361

  17. Measurement of retinal blood velocity

    NASA Astrophysics Data System (ADS)

    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.

  18. Fixation Strategies For Retinal Immunohistochemistry

    PubMed Central

    Stradleigh, Tyler W.; Ishida, Andrew T.

    2015-01-01

    Immunohistochemical and ex vivo anatomical studies have provided many glimpses of the variety, distribution, and signaling components of vertebrate retinal neurons. The beauty of numerous images published to date, and the qualitative and quantitative information they provide, indicate that these approaches are fundamentally useful. However, obtaining these images entailed tissue handling and exposure to chemical solutions that differ from normal extracellular fluid in composition, temperature, and osmolarity. Because the differences are large enough to alter intercellular and intracellular signaling in neurons, and because retinae are susceptible to crush, shear, and fray, it is natural to wonder if immunohistochemical and anatomical methods disturb or damage the cells they are designed to examine. Tissue fixation is typically incorporated to guard against this damage and is therefore critically important to the quality and significance of the harvested data. Here, we describe mechanisms of fixation; advantages and disadvantages of using formaldehyde and glutaraldehyde as fixatives during immunohistochemistry; and modifications of widely used protocols that have recently been found to improve cell shape preservation and immunostaining patterns, especially in proximal retinal neurons. PMID:25892361

  19. Neural remodeling in retinal degeneration.

    PubMed

    Marc, Robert E; Jones, Bryan W; Watt, Carl B; Strettoi, Enrica

    2003-09-01

    Mammalian retinal degenerations initiated by gene defects in rods, cones or the retinal pigmented epithelium (RPE) often trigger loss of the sensory retina, effectively leaving the neural retina deafferented. The neural retina responds to this challenge by remodeling, first by subtle changes in neuronal structure and later by large-scale reorganization. Retinal degenerations in the mammalian retina generally progress through three phases. Phase 1 initiates with expression of a primary insult, followed by phase 2 photoreceptor death that ablates the sensory retina via initial photoreceptor stress, phenotype deconstruction, irreversible stress and cell death, including bystander effects or loss of trophic support. The loss of cones heralds phase 3: a protracted period of global remodeling of the remnant neural retina. Remodeling resembles the responses of many CNS assemblies to deafferentation or trauma, and includes neuronal cell death, neuronal and glial migration, elaboration of new neurites and synapses, rewiring of retinal circuits, glial hypertrophy and the evolution of a fibrotic glial seal that isolates the remnant neural retina from the surviving RPE and choroid. In early phase 2, stressed photoreceptors sprout anomalous neurites that often reach the inner plexiform and ganglion cell layers. As death of rods and cones progresses, bipolar and horizontal cells are deafferented and retract most of their dendrites. Horizontal cells develop anomalous axonal processes and dendritic stalks that enter the inner plexiform layer. Dendrite truncation in rod bipolar cells is accompanied by revision of their macromolecular phenotype, including the loss of functioning mGluR6 transduction. After ablation of the sensory retina, Müller cells increase intermediate filament synthesis, forming a dense fibrotic layer in the remnant subretinal space. This layer invests the remnant retina and seals it from access via the choroidal route. Evidence of bipolar cell death begins in

  20. Hemodynamic management of subarachnoid hemorrhage.

    PubMed

    Treggiari, Miriam M

    2011-09-01

    Hemodynamic augmentation therapy is considered standard treatment to help prevent and treat vasospasm and delayed cerebral ischemia. Standard triple-H therapy combines volume expansion (hypervolemia), blood pressure augmentation (hypertension), and hemodilution. An electronic literature search was conducted of English-language papers published between 2000 and October 2010 that focused on hemodynamic augmentation therapies in patients with subarachnoid hemorrhage. Among the eligible reports identified, 11 addressed volume expansion, 10 blood pressure management, 4 inotropic therapy, and 12 hemodynamic augmentation in patients with unsecured aneurysms. While hypovolemia should be avoided, hypervolemia did not appear to confer additional benefits over normovolemic therapy, with an excess of side effects occurring in patients treated with hypervolemic targets. Overall, hypertension was associated with higher cerebral blood flow, regardless of volume status (normo- or hypervolemia), with neurological symptom reversal seen in two-thirds of treated patients. Limited data were available for evaluating inotropic agents or hemodynamic augmentation in patients with additional unsecured aneurysms. In the context of sparse data, no incremental risk of aneurysmal rupture has been reported with the induction of hemodynamic augmentation. PMID:21786046

  1. Hemorrhagic Aspects of Gaucher Disease

    PubMed Central

    Rosenbaum, Hanna

    2014-01-01

    Gaucher disease (GD) is an inherited lysosomal disorder, originating from deficient activity of the lysosomal enzyme glucocerebrosidase (GCase). Normally, GCase hydrolyzes glucocerebroside (GC) to glucose and ceramide; however, impaired activity of this enzyme leads to the accumulation of GC in macrophages, termed “Gaucher cells.” Gaucher disease is associated with hepatosplenomegaly, cytopenias, skeletal complications and in some forms involves the central nervous system. Coagulation abnormalities are common among GD patients due to impaired production and chronic consumption of coagulation factors. Bleeding phenomena are variable (as are other symptoms of GD) and include mucosal and surgical hemorrhages. Four main etiological factors account for the hemostatic defect in GD: thrombocytopenia, abnormal platelet function, reduced production of coagulation factors, and activation of fibrinolysis. Thrombocytopenia relates not only to hypersplenism and decreased megakaryopoiesis by the infiltrated bone marrow but also to immune thrombocytopenia. Autoimmunity, especially the induction of platelet antibody production, might cause persistent thrombocytopenia. Enzyme replacement therapy reverses only part of the impaired coagulation system in Gaucher disease. Other therapeutic and supportive measures should be considered to prevent and/or treat bleeding in GD. Gaucher patients should be evaluated routinely for coagulation abnormalities especially prior to surgery and dental and obstetric procedures. PMID:25386355

  2. Dengue hemorrhagic fever in infants.

    PubMed

    Hongsiriwon, Suchat

    2002-03-01

    A report of 19 cases of serologically-proven dengue hemorrhagic fever (DHF) in infants aged 3-12 months who were admitted to the Department of Pediatrics, Chon Buri Regional Hospital, Thailand, during 1995 to 1998. Subjects were 8 males and 11 females, with the peak age of 8 months. Four cases (21%) had DHF and other common co-infections ie pneumonia (2 cases), Staphylococcus aureus sepsis (1 case) and Haemophilus influenzae meningitis (1 case). The clinical manifestations of the 15 DHF cases were high fever (100%), coryza (93.3%), hepatomegaly (80%), drowsiness (53.3 %), and vomiting (46.7%); rash was observed in only 27%; one-fifth developed febrile convulsions. Sites of bleeding were the skin (petechiae) 58%, gastrointestinal system (melena) 16%, and mucous membrane (epistaxis) 5%; thrombocytopenia and increased hematocrit (> or =20%) were noted in 95% and 84% respectively. The majority of the patients (18 cases, 95%) had primary infection; only one (5%) had secondary infection. The clinical severity of the DHF was Grade I, II, and III (dengue shock syndrome) in 21%, 47% and 32% of cases respectively. After appropriate and effective management, all the infants recovered fully.

  3. Dengue and dengue hemorrhagic fever.

    PubMed

    Hayes, E B; Gubler, D J

    1992-04-01

    Hundreds of thousands of dengue cases are reported worldwide each year. Given the difficulty in obtaining full reporting, the actual number of human infections is probably much higher than the number reported. Dengue is usually a nonspecific febrile illness that resolves with supportive therapy but the clinical spectrum ranges from asymptomatic infection through severe hemorrhage and sudden fatal shock. The pathophysiology of the severe forms of dengue may be related to sequential infection with different serotypes, variations in virus virulence, interaction of the virus with environmental and host factors or a combination of these factors. Control of dengue at the present time is dependent on control of the principal vector mosquito, A. aegypti. Efforts to achieve such control are now focusing on community education and action towards eliminating this mosquito's breeding sites near human dwellings. Vaccine development continues, but at present the only way to avoid dengue in an area where it is endemic or epidemic is to use repellents and mosquito barriers. The movement of people to and from tropical areas makes dengue an important differential diagnosis in any patient with an acute illness and history of recent travel to tropical areas. Because of continued infestation of the southeastern United States with A. aegypti, indigenous transmission in the continental United States remains a public health concern.

  4. Assessment of blood-retinal barrier integrity.

    PubMed

    Vinores, S A

    1995-01-01

    The blood-retinal barrier consists of two components which are comprised of the retinal vascular endothelium and the retinal pigment epithelium, respectively. Its functional integrity can be recognized by tight junctions between these cells with a paucity of endocytic vesicles within them and the presence of the molecules that regulate the ionic and metabolic gradients that constitute the barrier. The barrier is compromised in several disease processes and by a variety of agents, but in most cases the location and mechanism for barrier failure is not understood. Perfusion with a variety of radiolabeled tracer molecules, vitreous fluorophotometry, or magnetic resonance imaging can be used to quantitate blood-retinal barrier leakage. Fluorescein angiography or magnetic resonance imaging can localize sites of leakage in vivo with limited resolution. Evans blue dye can be used to visualize blood-retinal barrier failure in gross pathological specimens and immuno-histochemical labeling of serum proteins such as albumin or fibrinogen can be used to localize sites of blood-retinal barrier breakdown by light microscopy. Tracers such as horseradish peroxidase, microperoxidase, or lanthanum, or the immunocytochemical demonstration of albumin can be used to reveal blood-retinal barrier breakdown at the ultrastructural level and provide insights into the mechanisms involved. This review discusses the advantages and limitations of each of these methods to aid in selection of the appropriate techniques to derive the desired information.

  5. A mechanical model of retinal detachment

    NASA Astrophysics Data System (ADS)

    Chou, Tom; Siegel, Michael

    2012-08-01

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

  6. Optical Coherence Tomography Angiography in Retinal Diseases

    PubMed Central

    Chalam, K. V.; Sambhav, Kumar

    2016-01-01

    Optical coherence tomography angiography (OCTA) is a new, non-invasive imaging system that generates volumetric data of retinal and choroidal layers. It has the ability to show both structural and blood flow information. Split-spectrum amplitude-decorrelation angiography (SSADA) algorithm (a vital component of OCTA software) helps to decrease the signal to noise ratio of flow detection thus enhancing visualization of retinal vasculature using motion contrast. Published studies describe potential efficacy for OCTA in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age related macular degeneration (AMD), retinal vascular occlusions and sickle cell disease. OCTA provides a detailed view of the retinal vasculature, which allows accurate delineation of microvascular abnormalities in diabetic eyes and vascular occlusions. It helps quantify vascular compromise depending upon the severity of diabetic retinopathy. OCTA can also elucidate the presence of choroidal neovascularization (CNV) in wet AMD. In this paper, we review the knowledge, available in English language publications regarding OCTA, and compare it with the conventional angiographic standard, fluorescein angiography (FA). Finally, we summarize its potential applications to retinal vascular diseases. Its current limitations include a relatively small field of view, inability to show leakage, and tendency for image artifacts. Further larger studies will define OCTA's utility in clinical settings and establish if the technology may offer a non-invasive option of visualizing the retinal vasculature, enabling us to decrease morbidity through early detection and intervention in retinal diseases. PMID:27195091

  7. Optical Coherence Tomography Angiography in Retinal Diseases.

    PubMed

    Chalam, K V; Sambhav, Kumar

    2016-01-01

    Optical coherence tomography angiography (OCTA) is a new, non-invasive imaging system that generates volumetric data of retinal and choroidal layers. It has the ability to show both structural and blood flow information. Split-spectrum amplitude-decorrelation angiography (SSADA) algorithm (a vital component of OCTA software) helps to decrease the signal to noise ratio of flow detection thus enhancing visualization of retinal vasculature using motion contrast. Published studies describe potential efficacy for OCTA in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age related macular degeneration (AMD), retinal vascular occlusions and sickle cell disease. OCTA provides a detailed view of the retinal vasculature, which allows accurate delineation of microvascular abnormalities in diabetic eyes and vascular occlusions. It helps quantify vascular compromise depending upon the severity of diabetic retinopathy. OCTA can also elucidate the presence of choroidal neovascularization (CNV) in wet AMD. In this paper, we review the knowledge, available in English language publications regarding OCTA, and compare it with the conventional angiographic standard, fluorescein angiography (FA). Finally, we summarize its potential applications to retinal vascular diseases. Its current limitations include a relatively small field of view, inability to show leakage, and tendency for image artifacts. Further larger studies will define OCTA's utility in clinical settings and establish if the technology may offer a non-invasive option of visualizing the retinal vasculature, enabling us to decrease morbidity through early detection and intervention in retinal diseases.

  8. Retinal venous pressure: the role of endothelin.

    PubMed

    Flammer, Josef; Konieczka, Katarzyna

    2015-01-01

    The retinal venous pressure (RVP) can be measured non-invasively. While RVP is equal to or slightly above intraocular pressure (IOP) in healthy people, it is often markedly increased in patients with eye or systemic diseases. Beside a mechanical obstruction, the main cause of such an elevation is a local dysregulation of a retinal vein, particularly a constriction induced by endothelin-1 (ET-1). A local increase of ET-1 can result from a high plasma level, as ET-1 can diffuse from the fenestrated capillaries of the choroid into the optic nerve head (ONH), bypassing the blood retinal barrier. A local increase can also result from increased local production either by a sick neighboring artery or retinal tissue. Generally, the main factors increasing ET-1 are inflammations and hypoxia, either locally or in a remote organ. RVP is known to be increased in patients with glaucoma, retinal vein occlusion (RVO), diabetic retinopathy, high mountain disease, and primary vascular dysregulation (PVD). PVD is the major vascular component of Flammer syndrome (FS). An increase of RVP decreases perfusion pressure, which heightens the risk for hypoxia. An increase of RVP also elevates transmural pressure, which in turn heightens the risk for retinal edema. In patients with RVO, a high level of RVP may not only be a consequence but also a potential cause of the occlusion; therefore, it risks causing a vicious circle. Narrow retinal arteries and particularly dilated retinal veins are known risk indicators for future cardiovascular events. As the major cause for such a retinal venous dilatation is an increased RVP, RVP may likely turn out to be an even stronger predictor. PMID:26504500

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

    PubMed

    Ma, Wenxin; Wong, Wai T

    2016-01-01

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

  10. Evaluation of vernier acuity near healed retinal laser lesions

    NASA Astrophysics Data System (ADS)

    Schmeisser, Elmar T.

    1997-05-01

    Seven Cynomolgus fasciculata who had graded laser lesions placed in own eye 6 years previously were evaluated for their vernier acuity by electrophysiologic recording techniques. In these experiments, 95 percent contrast vernier acuity targets were presented at high luminance levels to anesthetized primates. Visual evoked potentials were recorded by conventional means form scalp electrodes through hospital grade amplifiers. All animal testing was performed under IACUC approved protocols. The single q-switched pulses form a neodymium-YAG laser had produced lesions of 4 types: no visible change, minimal visible lesions, 'white dot' lesions and 'red dot' lesions in the eye at the time of placement. Single exposures had been made in four locations: 5 degrees superior, inferior and temporal to the fovea, and one foveally. Vernier recording proved somewhat successful in smaller animals with less than contained retinal hemorrhage lesions in the fovea. Initial analyses demonstrated a significant decrease of the pattern response signal/noise in the experimental eye overall, and an apparent relative loss of vernier signal in some lesioned eyes. Animals with the more severe lesions have somewhat degraded small patten responses and no recordable vernier response. Apparent lesser losses produced less effect.

  11. A multi-step system for screening and localization of hard exudates in retinal images

    NASA Astrophysics Data System (ADS)

    Bopardikar, Ajit S.; Bhola, Vishal; Raghavendra, B. S.; Narayanan, Rangavittal

    2012-03-01

    The number of people being affected by Diabetes mellitus worldwide is increasing at an alarming rate. Monitoring of the diabetic condition and its effects on the human body are therefore of great importance. Of particular interest is diabetic retinopathy (DR) which is a result of prolonged, unchecked diabetes and affects the visual system. DR is a leading cause of blindness throughout the world. At any point of time 25 - 44% of people with diabetes are afflicted by DR. Automation of the screening and monitoring process for DR is therefore essential for efficient utilization of healthcare resources and optimizing treatment of the affected individuals. Such automation would use retinal images and detect the presence of specific artifacts such as hard exudates, hemorrhages and soft exudates (that may appear in the image) to gauge the severity of DR. In this paper, we focus on the detection of hard exudates. We propose a two step system that consists of a screening step that classifies retinal images as normal or abnormal based on the presence of hard exudates and a detection stage that localizes these artifacts in an abnormal retinal image. The proposed screening step automatically detects the presence of hard exudates with a high sensitivity and positive predictive value (PPV ). The detection/localization step uses a k-means based clustering approach to localize hard exudates in the retinal image. Suitable feature vectors are chosen based on their ability to isolate hard exudates while minimizing false detections. The algorithm was tested on a benchmark dataset (DIARETDB1) and was seen to provide a superior performance compared to existing methods. The two-step process described in this paper can be embedded in a tele-ophthalmology system to aid with speedy detection and diagnosis of the severity of DR.

  12. Retinoids for Treatment of Retinal Diseases

    PubMed Central

    Palczewski, Krzysztof

    2010-01-01

    Knowledge about retinal photoreceptor signal transduction and the visual cycle required for normal eyesight has expanded exponentially over the past decade. Substantial progress in human genetics has allowed identification of candidate genes and complex networks underlying inherited retinal diseases. Natural mutations in animal models that mimic human diseases have been characterized and advanced genetic manipulation now permits generation of small mammalian models of human retinal diseases. Pharmacological repair of defective visual processes in animal models not only validates their involvement in vision but also provides great promise for developing improved therapies for the millions that are progressing towards blindness or are almost completely robbed of eyesight. PMID:20435355

  13. Fluid vitreous substitutes in vitreo retinal surgery.

    PubMed

    Saxena, S; Gopal, L

    1996-12-01

    Advances in the surgical instrumentation and vitreoretinal techniques have allowed intraoperative reapproximation of retina to a more normal position. The use of intravitreally injected liquid materials (viscoelastic liquids, liquid perfluorocarbons and silicone oil), as adjunctive agents to vitreo-retinal surgery play an important role in facilitating retinal reattachment. These materials are used as intraoperative instruments to re-establish intraocular volume, assist in separating membranes adherent to the retina, manipulate retinal detachments and mechanically flatten detached retina. Over the longer term, silicone oil maintains intraocular tamponade. One should be cognizant of the potential uses, benefits and risks of each of these vitreous substitutes.

  14. [New drug therapy for retinal degeneration].

    PubMed

    Ohguro, Hiroshi

    2008-01-01

    Retinitis pigmentosa (RP) is an inherited retinal degeneration characterized by nyctalopia, ring scotoma, and bone-spicule pigmentation of the retina. So far, no effective therapy has been found for RP. As a possible molecular etiology of RP, retina-specific gene deficits are most likely involved, but little has been identified in terms of intracellular mechanisms leading to retinal photoreceptor cell death at post-translational levels. In order to find an effective therapy for RP, we must look for underlying common mechanisms that are responsible for the development of RP, instead of designing a specific therapy for each of the RP types with different causes. Therefore, in the present study, several animal models with different causes of RP were studied, including (1)Royal College of Surgeons (RCS) rats with a deficit of retinal pigment epithelium (RPE) function caused by rhodopsin mutation; (2) P23H rats, (3) S334ter rats, (4) photo stress rats, (5) retinal degeneration (rd) mice with a deficit of phosphodiesterase(PDE) function; and (6) cancer-associated retinopathy (CAR) model rats with a deficit of recoverin-dependent photoreceptor adaptation function. In each of these models, the following assessments were made in order to elucidate common pathological mechanisms among the models: (1) retinal function assessed by electroretinogram (ERG), (2) retinal morphology, (3) retinoid analysis, (4) rhodopsin regeneration, (5) rhodopsin phosphorylation and dephosphorylation, and (6) cytosolic cGMP levels. We found that unregulated photoreceptor adaptation processes caused by an imbalance of rhodopsin phosphorylation and dephosphorylation caused retinal dysfunction leading to photoreceptor cell death. As possible candidate drugs for normalizing these retinal dysfunctions and stopping further retinal degeneration, nilvadipine, a Ca channel blocker, retinoid derivatives, and anthocyanine were chosen and tested to determine their effect on the above animal models with

  15. Surgical treatment of central retinal vein occlusion.

    PubMed

    Berker, Nilufer; Batman, Cosar

    2008-05-01

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

  16. Retinal Stimulation on Rabbit Using Complementary Metal Oxide Semiconductor Based Multichip Flexible Stimulator toward Retinal Prosthesis

    NASA Astrophysics Data System (ADS)

    Tokuda, Takashi; Asano, Ryosuke; Sugitani, Sachie; Taniyama, Mari; Terasawa, Yasuo; Nunoshita, Masahiro; Nakauchi, Kazuaki; Fujikado, Takashi; Tano, Yasuo; Ohta, Jun

    2008-04-01

    The Functionality of a complementary metal oxide semiconductor (CMOS) LSI-based, multichip flexible retinal stimulator was demonstrated in retinal stimulation experiments on rabbits. A 1×4-configured multichip stimulator was fabricated for application to experiments on animals. An experimental procedure including surgical operations was developed, and retinal stimulation was performed with the fabricated multichip stimulator. Neural responses on the visual cortex were successfully evoked by the fabricated stimulator. The stimulator is confirmed to be applicable to acute animal experiments.

  17. Supernova hemorrhage: obliterative hemorrhage of brain arteriovenous malformations following γ knife radiosurgery.

    PubMed

    Alexander, Matthew D; Hetts, Steven W; Young, William L; Halbach, Van V; Dowd, Christopher F; Higashida, Randall T; English, Joey D

    2012-09-01

    Hemorrhage represents the most feared complication of cerebral arteriovenous malformations (AVMs) in both untreated patients and those treated with gamma knife radiosurgery. Radiosurgery does not immediately lead to obliteration of the malformation, which often does not occur until years following treatment. Post-obliteration hemorrhage is rare, occurring months to years after radiosurgery, and has been associated with residual or recurrent AVM despite prior apparent nidus elimination. Three cases are reported of delayed intracranial hemorrhage in patients with cerebral AVMs treated with radiosurgery in which no residual AVM was found on catheter angiography at the time of delayed post-treatment hemorrhage. That the pathophysiology of these hemorrhages involves progressive venous outflow occlusion is speculated and the possible mechanistic link to subsequent vascular rupture is discussed.

  18. A Case of Sudden Deafness with Intralabyrinthine Hemorrhage Intralabyrinthine Hemorrhage and Sudden Deafness.

    PubMed

    Park, Jeong Jin; Jeong, Se Won; Lee, Jae Wook; Han, Su-Jin

    2015-12-01

    Sudden hearing deterioration may occur in our population, but it is difficult to explain the exact pathophysiology and the cause. Magnetic resonance imaging (MRI) in sudden sensorineural hearing loss (SSNHL) is usually useful to evaluate neural lesions such as acoustic schwannoma and hemorrhage in labyrinth. Recently some cases of SSNHL caused by intralabyrintine hemorrhage were reported by the advance of MRI. In the case of intralabyrintine hemorrhage, MRI showed a hyperintense signal in the labyrinth on the pre-contrast and contrast enhanced T1-weighted image and relatively weak intensity on T2-weighted image. The prognosis SSNHL by intralabyrintine hemorrhage is generally known to be poor. We report a case of sudden deafness with intralabyrintine hemorrhage who has a history of anticoagulant administration, with a review of literature.

  19. Pulmonary hemorrhage syndrome associated with an autochthonous case of dengue hemorrhagic fever.

    PubMed

    Setlik, Robert F; Ouellette, Daniel; Morgan, Julia; McAllister, C Kenneth; Dorsey, David; Agan, Brian K; Horvath, Lynn; Zimmerman, Michelle K; Purcell, Bret

    2004-07-01

    Dengue fever is a major public health problem worldwide. Dengue hemorrhagic fever, a much rarer form of the disease, occurs when a person previously infected with dengue is re-infected with a different viral serotype. In recent years the infection rates of dengue and both clinical syndromes have increased along the United States-Mexico border. We present the case of a 61-year-old Laotian female who presented with a 1-week history of fever, altered mental status, oral ulceration, and rash. The patient developed diffuse pulmonary hemorrhage and anemia requiring multiple transfusions. She eventually sustained multi-organ system failure and expired. Both the titer data and serologies were consistent with the diagnosis of dengue hemorrhagic fever. We hypothesize that this syndrome was the result of re-infection occurring within the United States. This case is also unusual in that it is the second reported in the literature of pulmonary hemorrhages associated with dengue hemorrhagic fever.

  20. Intraparenchymal hemorrhage after heroin use.

    PubMed

    Kumar, Neha; Bhalla, Mary Colleen; Frey, Jennifer A; Southern, Alison

    2015-08-01

    Heroin-associated stroke is a rare complication of use. Various proposed mechanisms of heroin-associated ischemic stroke have been proposed, including the following: cardioembolism in the setting of infective endocarditis, hypoxic ischemic brain injury in the setting of hypoxemia and hypotension, and infective arteritis or vasculitis from drug adulterants. A previously healthy 28-year-old woman presented to the emergency department with altered mental status and normal vitals after she was found wandering outside her apartment. During ambulance transport, she endorsed heroin use. The patient was alert but could not recall her name, place, or time. She intermittently responded "I don't know" to questioning and could not perform simple commands. No motor or sensory deficits were apparent other than sluggish pinpoint pupils. There were no signs of trauma other than antecubital track marks. Her laboratory results were unremarkable. Reevaluation at 2 hours after presentation showed persistent confusion and disorientation. A computed tomographic scan of the head was obtained, which showed a large 5.1 × 5-cm intraparenchymal hemorrhage in the left frontal lobe, vasogenic edema, and a 5-mm midline shift. A workup for cardioembolic, vasculitis, and other etiologies for stroke did not reveal an underlying cause. The patient remained confused with significant memory loss throughout her hospital stay and was eventually discharged to a long-term care facility. Drug abuse should be considered a risk factor for stoke in young adults. In patients with persistent neurologic deficits, physicians must be vigilant and order appropriate workup while managing drug overdose.

  1. Hemorrhagic fever with renal syndrome.

    PubMed

    Lee, H W; van der Groen, G

    1989-01-01

    Hantaviruses, the causative agents of HFRS, have become more widely recognized. Epidemiologic evidence indicates that these pathogens are distributed worldwide. People who come into close contact with infected rodents in urban, rural and laboratory environments are at particular risk. Transmission to man occurs mainly via the respiratory tract. The epidemiology of the hantaviruses is intimately linked to the ecology of their principal vertebrate hosts. Four distinct viruses are now recognized within the hantavirus genus and that number is likely to increase to six very soon; however, further investigations are necessary. Much more work is still needed before we fully understand the wide spectrum of clinical signs and symptoms of HFRS as well as the pathogenicity of the different viruses in the hantavirus genus of the Bunyaviridae family. HFRS is difficult to diagnose on clinical grounds alone and serological evidence is often needed. A fourfold rise in IgG antibody titer in a 1-week interval, and the presence of the IgM type of antibodies against hantaviruses are good evidence for an acute hantavirus infection. Physicians should be alert for HFRS each time they deal with patients with acute febrile flu-like illness, renal failure of unknown origin and sometimes hepatic dysfunction. Especially the mild form of HFRS is difficult to diagnose. Acute onset, headache, fever, increased serum creatinine, proteinuria and polyuria are signs and symptoms compatible with a mild form of HFRS. Differential diagnosis should be considered for the following diseases in the endemic areas of HFRS: acute renal failure, hemorrhagic scarlet fever, acute abdomen, leptospirosis, scrub typhus, murine typhus, spotted fevers, non-A, non-B hepatitis, Colorado tick fever, septicemia, dengue, heartstroke and DIC. Treatment of HFRS is mainly supportive. Recently, however, treatment of HFRS patients with ribavirin in China and Korea, within 7 days after onset of fever, resulted in a reduced

  2. Management of Acute Submacular Hemorrhage with Intravitreal Injection of Tenecteplase, Anti-vascular Endothelial Growth Factor and Gas

    PubMed Central

    Lee, Jung Pil; Park, Jun Sang; Kwon, Oh Woong; You, Yong Sung

    2016-01-01

    Purpose To evaluate the visual and anatomical outcomes for neovascular age-related macular degeneration with submacular hemorrhage after intravitreal injections of tenecteplase (TNK), anti-vascular endothelial growth factor (VEGF) and expansile gas. Methods This study was a retrospective clinical case series following 25 eyes of 25 patients. All patients received a triple injection using 0.05 mL TNK (50 µg), 0.05 mL anti-VEGF and 0.3 mL of perfluoropropane gas. Retreatment with anti-VEGF was performed as needed. Preoperative and postoperative best-corrected visual acuity and central retinal thickness were analyzed. Results The mean logarithm of the minimum angle of resolution of best-corrected visual acuity improved significantly from 1.09 ± 0.77 at baseline to 0.52 ± 0.60 at 12 months (p < 0.001). The mean central retinal thickness also improved significantly from 545 ± 156 at baseline to 266 ± 107 at 12 months (p < 0.001). A visual improvement of 0.3 logarithm of the minimum angle of resolution unit or more was achieved in 15 eyes (60%). During the 12 postoperative months, an average of 4.04 intravitreal anti-VEGF injections was applied. Conclusions A triple injection of TNK, anti-VEGF, and a gas appears to be safe and effective for the treatment of submacular hemorrhage secondary to neovascular age-related macular degeneration. PMID:27247518

  3. Gene therapy for retinal degeneration.

    PubMed

    Reichel, M B; Ali, R R; Hunt, D M; Bhattacharya, S S

    1997-01-01

    Inherited retinal degenerations are a group of diseases leading to blindness through progressive loss of vision in many patients. Although with the cloning of more and more disease genes the knowledge on the molecular genetics of these conditions and on the apoptotic pathway as the common disease mechanism is steadily increasing, there is still no cure for those affected. In recent years, new experimental treatments have evolved through the efforts of many investigators and have been explored in animal models. The rationale of the different strategies for developing a treatment based on gene replacement or rescue of the diseased neuronal tissue with growth factors will be outlined and discussed in this paper. PMID:9323717

  4. Integration of retinal image sequences

    NASA Astrophysics Data System (ADS)

    Ballerini, Lucia

    1998-10-01

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

  5. Overview of ultrasound-induced lung hemorrhage

    NASA Astrophysics Data System (ADS)

    O'Brien, William D.; Simpson, Douglas G.; Frizzell, Leon A.; Oelze, Michael L.; Zachary, James F.

    2003-10-01

    It is well documented that ultrasound-induced lung hemorrhage can occur in mice, rats, rabbits, pigs, and monkeys. Our own experimental studies have focused on mice, rats, and pigs as animal models. The characteristics of the lesions produced in mice, rats and pigs were similar to those described in studies by our research group and others, suggesting a common pathogenesis for the initiation and propagation of the lesions at the macroscopic and microscopic levels. Five experimental in vivo studies have been conducted to evaluate whether cavitation is responsible for ultrasound-induced lung hemorrhage. The studies evaluated the dependencies of hydrostatic pressure, frequency, pulse polarity, contrast agents and lung inflation, and the results of each study appeared inconsistent with the hypothesis that the mechanism for the production of a lung hemorrhage was inertial cavitation. Other dependencies evaluated included beam width, pulse repetition frequency, pulse duration, exposure duration, and animal species and age. The thresholds for producing ultrasound-induced lung hemorrhage, in general, were less than the FDA's regulatory limit of a Mechanical Index (MI) of 1.9. Further, the MI does not appear to provide a risk-based index for lung hemorrhage. [Work supported by NIH Grant No. R01EB02641.

  6. Intravesical silver nitrate for refractory hemorrhagic cystitis

    PubMed Central

    Montgomery, Brian D.; Boorjian, Stephen A.; Ziegelmann, Matthew J.; Joyce, Daniel D.; Linder, Brian J.

    2016-01-01

    Objective Hemorrhagic cystitis is a challenging clinical entity with limited evidence available to guide treatment. The use of intravesical silver nitrate has been reported, though supporting literature is sparse. Here, we sought to assess outcomes of patients treated with intravesical silver nitrate for refractory hemorrhagic cystitis. Material and methods We identified nine patients with refractory hemorrhagic cystitis treated at our institution with intravesical silver nitrate between 2000–2015. All patients had failed previous continuous bladder irrigation with normal saline and clot evacuation. Treatment success was defined as requiring no additional therapy beyond normal saline irrigation after silver nitrate instillation prior to hospital discharge. Results Median patient age was 80 years (IQR 73, 82). Radiation was the most common etiology for hemorrhagic cystitis 89% (8/9). Two patients underwent high dose (0.1%–0.4%) silver nitrate under anesthesia, while the remaining seven were treated with doses from 0.01% to 0.1% via continuous bladder irrigation for a median of 3 days (range 2–4). All nine patients (100%) had persistent hematuria despite intravesical silver nitrate therapy, requiring additional interventions and red blood cell transfusion during the hospitalization. There were no identified complications related to intravesical silver nitrate instillation. Conclusion Although well tolerated, we found that intravesical silver nitrate was ineffective for bleeding control, suggesting a limited role for this agent in the management of patients with hemorrhagic cystitis.

  7. Intravesical silver nitrate for refractory hemorrhagic cystitis

    PubMed Central

    Montgomery, Brian D.; Boorjian, Stephen A.; Ziegelmann, Matthew J.; Joyce, Daniel D.; Linder, Brian J.

    2016-01-01

    Objective Hemorrhagic cystitis is a challenging clinical entity with limited evidence available to guide treatment. The use of intravesical silver nitrate has been reported, though supporting literature is sparse. Here, we sought to assess outcomes of patients treated with intravesical silver nitrate for refractory hemorrhagic cystitis. Material and methods We identified nine patients with refractory hemorrhagic cystitis treated at our institution with intravesical silver nitrate between 2000–2015. All patients had failed previous continuous bladder irrigation with normal saline and clot evacuation. Treatment success was defined as requiring no additional therapy beyond normal saline irrigation after silver nitrate instillation prior to hospital discharge. Results Median patient age was 80 years (IQR 73, 82). Radiation was the most common etiology for hemorrhagic cystitis 89% (8/9). Two patients underwent high dose (0.1%–0.4%) silver nitrate under anesthesia, while the remaining seven were treated with doses from 0.01% to 0.1% via continuous bladder irrigation for a median of 3 days (range 2–4). All nine patients (100%) had persistent hematuria despite intravesical silver nitrate therapy, requiring additional interventions and red blood cell transfusion during the hospitalization. There were no identified complications related to intravesical silver nitrate instillation. Conclusion Although well tolerated, we found that intravesical silver nitrate was ineffective for bleeding control, suggesting a limited role for this agent in the management of patients with hemorrhagic cystitis. PMID:27635296

  8. Regulatory and Economic Considerations of Retinal Drugs.

    PubMed

    Shah, Ankoor R; Williams, George A

    2016-01-01

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

  9. [Ocular hypertension after surgery for retinal detachment].

    PubMed

    Muşat, O; Cristescu, R; Coman, Corina; Asandi, R

    2012-01-01

    This papers presents a case of a patient with retinal detachement, 3 days ago operated (posterior vitrectomy internal tamponament with silicon oil 1000) who develop increased ocular pressure following silicon oil output in the anterior chamber.

  10. [Retinal vein occlusion in a young patient].

    PubMed

    Zemba, Mihail; Ochinciuc, Uliana; Sarbu, Laura; Avram, Corina; Camburu, Raluca; Stamate, Alina

    2013-01-01

    We present a case report of a 27 years old pacient with central retinal vein occlussion and macular edema. The pacient has a significant reduction of the macular aedema with complete recovery of vision after the treatment.

  11. Retinal fractals and acute lacunar stroke.

    PubMed

    Cheung, Ning; Liew, Gerald; Lindley, Richard I; Liu, Erica Y; Wang, Jie Jin; Hand, Peter; Baker, Michelle; Mitchell, Paul; Wong, Tien Y

    2010-07-01

    This study aimed to determine whether retinal fractal dimension, a quantitative measure of microvascular branching complexity and density, is associated with lacunar stroke. A total of 392 patients presenting with acute ischemic stroke had retinal fractal dimension measured from digital photographs, and lacunar infarct ascertained from brain imaging. After adjusting for age, gender, and vascular risk factors, higher retinal fractal dimension (highest vs lowest quartile and per standard deviation increase) was independently and positively associated with lacunar stroke (odds ratio [OR], 4.27; 95% confidence interval [CI], 1.49-12.17 and OR, 1.85; 95% CI, 1.20-2.84, respectively). Increased retinal microvascular complexity and density is associated with lacunar stroke.

  12. Imaging retinal mosaics in the living eye.

    PubMed

    Rossi, E A; Chung, M; Dubra, A; Hunter, J J; Merigan, W H; Williams, D R

    2011-03-01

    Adaptive optics imaging of cone photoreceptors has provided unique insight into the structure and function of the human visual system and has become an important tool for both basic scientists and clinicians. Recent advances in adaptive optics retinal imaging instrumentation and methodology have allowed us to expand beyond cone imaging. Multi-wavelength and fluorescence imaging methods with adaptive optics have allowed multiple retinal cell types to be imaged simultaneously. These new methods have recently revealed rod photoreceptors, retinal pigment epithelium (RPE) cells, and the smallest retinal blood vessels. Fluorescence imaging coupled with adaptive optics has been used to examine ganglion cells in living primates. Two-photon imaging combined with adaptive optics can evaluate photoreceptor function non-invasively in the living primate retina.

  13. Imaging retinal mosaics in the living eye

    PubMed Central

    Rossi, E A; Chung, M; Dubra, A; Hunter, J J; Merigan, W H; Williams, D R

    2011-01-01

    Adaptive optics imaging of cone photoreceptors has provided unique insight into the structure and function of the human visual system and has become an important tool for both basic scientists and clinicians. Recent advances in adaptive optics retinal imaging instrumentation and methodology have allowed us to expand beyond cone imaging. Multi-wavelength and fluorescence imaging methods with adaptive optics have allowed multiple retinal cell types to be imaged simultaneously. These new methods have recently revealed rod photoreceptors, retinal pigment epithelium (RPE) cells, and the smallest retinal blood vessels. Fluorescence imaging coupled with adaptive optics has been used to examine ganglion cells in living primates. Two-photon imaging combined with adaptive optics can evaluate photoreceptor function non-invasively in the living primate retina. PMID:21390064

  14. Stem Cells, Retinal Ganglion Cells, and Glaucoma

    PubMed Central

    Sluch, Valentin M.; Zack, Donald J.

    2015-01-01

    Retinal ganglion cells represent an essential neuronal cell type for vision. These cells receive inputs from light-sensing photoreceptors via retinal interneurons and then relay these signals to the brain for further processing. Retinal ganglion cell diseases that result in cell death, e.g. glaucoma, often lead to permanent damage since mammalian nerves do not regenerate. Stem cell differentiation can generate cells needed for replacement or can be used to generate cells capable of secreting protective factors to promote survival. In addition, stem cell-derived cells can be used in drug screening research. Here, we discuss the current state of stem cell research potential for interference in glaucoma and other optic nerve diseases with a focus on stem cell differentiation to retinal ganglion cells. PMID:24732765

  15. Retinal Detachment: Torn or Detached Retina Treatment

    MedlinePlus

    ... of these procedures create a scar that helps seal the retina to the back of the eye. ... around the retinal tear. The scarring that results seals the retina to the underlying tissue, helping to ...

  16. Regulatory and Economic Considerations of Retinal Drugs.

    PubMed

    Shah, Ankoor R; Williams, George A

    2016-01-01

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

  17. What Is Next for Retinal Gene Therapy?

    PubMed

    Vandenberghe, Luk H

    2015-10-01

    The field of gene therapy for retinal blinding disorders is experiencing incredible momentum, justified by hopeful results in early stage clinical trials for inherited retinal degenerations. The premise of the use of the gene as a drug has come a long way, and may have found its niche in the treatment of retinal disease. Indeed, with only limited treatment options available for retinal indications, gene therapy has been proven feasible, safe, and effective and may lead to durable effects following a single injection. Here, we aim at putting into context the promise and potential, the technical, clinical, and economic boundaries limiting its application and development, and speculate on a future in which gene therapy is an integral component of ophthalmic clinical care.

  18. What Is Next for Retinal Gene Therapy?

    PubMed Central

    Vandenberghe, Luk H.

    2015-01-01

    The field of gene therapy for retinal blinding disorders is experiencing incredible momentum, justified by hopeful results in early stage clinical trials for inherited retinal degenerations. The premise of the use of the gene as a drug has come a long way, and may have found its niche in the treatment of retinal disease. Indeed, with only limited treatment options available for retinal indications, gene therapy has been proven feasible, safe, and effective and may lead to durable effects following a single injection. Here, we aim at putting into context the promise and potential, the technical, clinical, and economic boundaries limiting its application and development, and speculate on a future in which gene therapy is an integral component of ophthalmic clinical care. PMID:25877395

  19. Photoreceptor Cells Influence Retinal Vascular Degeneration in Mouse Models of Retinal Degeneration and Diabetes

    PubMed Central

    Liu, Haitao; Tang, Jie; Du, Yunpeng; Saadane, Aicha; Tonade, Deoye; Samuels, Ivy; Veenstra, Alex; Palczewski, Krzysztof; Kern, Timothy S.

    2016-01-01

    Purpose Loss of photoreceptor cells is associated with retinal vascular degeneration in retinitis pigmentosa, whereas the presence of photoreceptor cells is implicated in vascular degeneration in diabetic retinopathy. To investigate how both the absence and presence of photoreceptors could damage the retinal vasculature, we compared two mouse models of photoreceptor degeneration (opsin−/− and RhoP23H/P23H ) and control C57Bl/5J mice, each with and without diabetes. Methods Retinal thickness, superoxide, expression of inflammatory proteins, ERG and optokinetic responses, leukocyte cytotoxicity, and capillary degeneration were evaluated at 1 to 10 months of age using published methods. Results Retinal photoreceptor cells degenerated completely in the opsin mutants by 2 to 4 months of age, and visual function subsided correspondingly. Retinal capillary degeneration was substantial while photoreceptors were still present, but slowed after the photoreceptors degenerated. Diabetes did not further exacerbate capillary degeneration in these models of photoreceptor degeneration, but did cause capillary degeneration in wild-type animals. Photoreceptor cells, however, did not degenerate in wild-type diabetic mice, presumably because the stress responses in these cells were less than in the opsin mutants. Retinal superoxide and leukocyte damage to retinal endothelium contributed to the degeneration of retinal capillaries in diabetes, and leukocyte-mediated damage was increased in both opsin mutants during photoreceptor cell degeneration. Conclusions Photoreceptor cells affect the integrity of the retinal microvasculature. Deterioration of retinal capillaries in opsin mutants was appreciable while photoreceptor cells were present and stressed, but was less after photoreceptors degenerated. This finding proves relevant to diabetes, where persistent stress in photoreceptors likewise contributes to capillary degeneration. PMID:27548901

  20. Retinal Vascular Fractals and Cognitive Impairment

    PubMed Central

    Ong, Yi-Ting; Hilal, Saima; Cheung, Carol Yim-lui; Xu, Xin; Chen, Christopher; Venketasubramanian, Narayanaswamy; Wong, Tien Yin; Ikram, Mohammad Kamran

    2014-01-01

    Background Retinal microvascular network changes have been found in patients with age-related brain diseases such as stroke and dementia including Alzheimer's disease. We examine whether retinal microvascular network changes are also present in preclinical stages of dementia. Methods This is a cross-sectional study of 300 Chinese participants (age: ≥60 years) from the ongoing Epidemiology of Dementia in Singapore study who underwent detailed clinical examinations including retinal photography, brain imaging and neuropsychological testing. Retinal vascular parameters were assessed from optic disc-centered photographs using a semiautomated program. A comprehensive neuropsychological battery was administered, and cognitive function was summarized as composite and domain-specific Z-scores. Cognitive impairment no dementia (CIND) and dementia were diagnosed according to standard diagnostic criteria. Results Among 268 eligible nondemented participants, 78 subjects were categorized as CIND-mild and 69 as CIND-moderate. In multivariable adjusted models, reduced retinal arteriolar and venular fractal dimensions were associated with an increased risk of CIND-mild and CIND-moderate. Reduced fractal dimensions were associated with poorer cognitive performance globally and in the specific domains of verbal memory, visuoconstruction and visuomotor speed. Conclusion A sparser retinal microvascular network, represented by reduced arteriolar and venular fractal dimensions, was associated with cognitive impairment, suggesting that early microvascular damage may be present in preclinical stages of dementia. PMID:25298774

  1. Robotic Assisted Cannulation of Occluded Retinal Veins

    PubMed Central

    Meenink, Thijs C. M.; Janssens, Tom; Vanheukelom, Valerie; Naus, Gerrit J. L.; Beelen, Maarten J.; Meers, Caroline; Jonckx, Bart; Stassen, Jean-Marie

    2016-01-01

    Purpose To develop a methodology for cannulating porcine retinal venules using a robotic assistive arm after inducing a retinal vein occlusion using the photosensitizer rose bengal. Methodology Retinal vein occlusions proximal to the first vascular branch point were induced following intravenous injection of rose bengal by exposure to 532nm laser light delivered by slit-lamp or endolaser probe. Retinal veins were cannulated by positioning a glass catheter tip using a robotically controlled micromanipulator above venules with an outer diameter of 80μm or more and performing a preset piercing maneuver, controlled robotically. The ability of a balanced salt (BSS) solution to remove an occlusion by repeat distention of the retinal vein was also assessed. Results Cannulation using the preset piercing program was successful in 9 of 9 eyes. Piercing using the micromanipulator under manual control was successful in only 24 of 52 attempts, with several attempts leading to double piercing. The best location for cannulation was directly proximal to the occlusion. Infusion of BSS did not result in the resolution of the occlusion. Conclusion Cannulation of venules using a robotic microassistive arm can be achieved with consistency, provided the piercing is robotically driven. The model appears robust enough to allow testing of therapeutic strategies aimed at eliminating a retinal vein thrombus and its evolution over time. PMID:27676261

  2. Retinal synaptic regeneration via microfluidic guiding channels.

    PubMed

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

    2015-08-28

    In vitro culture of dissociated retinal neurons is an important model for investigating retinal synaptic regeneration (RSR) and exploring potentials in artificial retina. Here, retinal precursor cells were cultured in a microfluidic chip with multiple arrays of microchannels in order to reconstruct the retinal neuronal synapse. The cultured retinal cells were physically connected through microchannels. Activation of electric signal transduction by the cells through the microchannels was demonstrated by administration of glycinergic factors. In addition, an image-based analytical method was used to quantify the synaptic connections and to assess the kinetics of synaptic regeneration. The rate of RSR decreased significantly below 100 μM of inhibitor glycine and then approached to a relatively constant level at higher concentrations. Furthermore, RSR was enhanced by chemical stimulation with potassium chloride. Collectively, the microfluidic synaptic regeneration chip provides a novel tool for high-throughput investigation of RSR at the cellular level and may be useful in quality control of retinal precursor cell transplantation.

  3. Digital imaging-based retinal photocoagulation system

    NASA Astrophysics Data System (ADS)

    Barrett, Steven F.; Wright, Cameron H. G.; Oberg, Erik D.; Rockwell, Benjamin A.; Cain, Clarence P.; Rylander, Henry G., III; Welch, Ashley J.

    1997-05-01

    Researchers at the USAF Academy and the University of Texas are developing a computer-assisted retinal photocoagulation system for the treatment of retinal disorders (i.e. diabetic retinopathy, retinal tears). Currently, ophthalmologists manually place therapeutic retinal lesions, an acquired technique that is tiring for both the patient and physician. The computer-assisted system under development can rapidly and safely place multiple therapeutic lesions at desired locations on the retina in a matter of seconds. Separate prototype subsystems have been developed to control lesion depth during irradiation and lesion placement to compensate for retinal movement. Both subsystems have been successfully demonstrated in vivo on pigmented rabbits using an argon continuous wave laser. Two different design approaches are being pursued to combine the capabilities of both subsystems: a digital imaging-based system and a hybrid analog-digital system. This paper will focus on progress with the digital imaging-based prototype system. A separate paper on the hybrid analog-digital system, `Hybrid Retinal Photocoagulation System', is also presented in this session.

  4. Retinal imaging using adaptive optics technology☆

    PubMed Central

    Kozak, Igor

    2014-01-01

    Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effect of wave front distortions. Retinal imaging using AO aims to compensate for higher order aberrations originating from the cornea and the lens by using deformable mirror. The main application of AO retinal imaging has been to assess photoreceptor cell density, spacing, and mosaic regularity in normal and diseased eyes. Apart from photoreceptors, the retinal pigment epithelium, retinal nerve fiber layer, retinal vessel wall and lamina cribrosa can also be visualized with AO technology. Recent interest in AO technology in eye research has resulted in growing number of reports and publications utilizing this technology in both animals and humans. With the availability of first commercially available instruments we are making transformation of AO technology from a research tool to diagnostic instrument. The current challenges include imaging eyes with less than perfect optical media, formation of normative databases for acquired images such as cone mosaics, and the cost of the technology. The opportunities for AO will include more detailed diagnosis with description of some new findings in retinal diseases and glaucoma as well as expansion of AO into clinical trials which has already started. PMID:24843304

  5. Retinal synaptic regeneration via microfluidic guiding channels

    PubMed Central

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

    2015-01-01

    In vitro culture of dissociated retinal neurons is an important model for investigating retinal synaptic regeneration (RSR) and exploring potentials in artificial retina. Here, retinal precursor cells were cultured in a microfluidic chip with multiple arrays of microchannels in order to reconstruct the retinal neuronal synapse. The cultured retinal cells were physically connected through microchannels. Activation of electric signal transduction by the cells through the microchannels was demonstrated by administration of glycinergic factors. In addition, an image-based analytical method was used to quantify the synaptic connections and to assess the kinetics of synaptic regeneration. The rate of RSR decreased significantly below 100 μM of inhibitor glycine and then approached to a relatively constant level at higher concentrations. Furthermore, RSR was enhanced by chemical stimulation with potassium chloride. Collectively, the microfluidic synaptic regeneration chip provides a novel tool for high-throughput investigation of RSR at the cellular level and may be useful in quality control of retinal precursor cell transplantation. PMID:26314276

  6. Retinal imaging using adaptive optics technology.

    PubMed

    Kozak, Igor

    2014-04-01

    Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effect of wave front distortions. Retinal imaging using AO aims to compensate for higher order aberrations originating from the cornea and the lens by using deformable mirror. The main application of AO retinal imaging has been to assess photoreceptor cell density, spacing, and mosaic regularity in normal and diseased eyes. Apart from photoreceptors, the retinal pigment epithelium, retinal nerve fiber layer, retinal vessel wall and lamina cribrosa can also be visualized with AO technology. Recent interest in AO technology in eye research has resulted in growing number of reports and publications utilizing this technology in both animals and humans. With the availability of first commercially available instruments we are making transformation of AO technology from a research tool to diagnostic instrument. The current challenges include imaging eyes with less than perfect optical media, formation of normative databases for acquired images such as cone mosaics, and the cost of the technology. The opportunities for AO will include more detailed diagnosis with description of some new findings in retinal diseases and glaucoma as well as expansion of AO into clinical trials which has already started. PMID:24843304

  7. Retinal synaptic regeneration via microfluidic guiding channels.

    PubMed

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

    2015-01-01

    In vitro culture of dissociated retinal neurons is an important model for investigating retinal synaptic regeneration (RSR) and exploring potentials in artificial retina. Here, retinal precursor cells were cultured in a microfluidic chip with multiple arrays of microchannels in order to reconstruct the retinal neuronal synapse. The cultured retinal cells were physically connected through microchannels. Activation of electric signal transduction by the cells through the microchannels was demonstrated by administration of glycinergic factors. In addition, an image-based analytical method was used to quantify the synaptic connections and to assess the kinetics of synaptic regeneration. The rate of RSR decreased significantly below 100 μM of inhibitor glycine and then approached to a relatively constant level at higher concentrations. Furthermore, RSR was enhanced by chemical stimulation with potassium chloride. Collectively, the microfluidic synaptic regeneration chip provides a novel tool for high-throughput investigation of RSR at the cellular level and may be useful in quality control of retinal precursor cell transplantation. PMID:26314276

  8. Global aphasia due to left thalamic hemorrhage.

    PubMed

    Ozeren, Ali; Koc, Filiz; Demirkiran, Meltem; Sönmezler, Abdurrahman; Kibar, Mustafa

    2006-12-01

    Global aphasia is an acquired language disorder characterized by severe impairments in all modalities of language. The specific sites of injury commonly include Wernike's and Broca's areas and result from large strokes--particularly those involving the internal carotid or middle cerebral arteries. Rarely, deep subcortical lesions may cause global aphasia. We present three cases with global aphasia due to a more rare cause: left thalamic hemorrhage. Their common feature was the large size of the hemorrhage and its extension to the third ventricule. HMPAO-SPECT in one of the cases revealed ipsilateral subcortical, frontotemporal cortical and right frontal cortical hypoperfusion. Left thalamic hemorrhage should be considered in the differential diagnosis of global aphasia. PMID:17114855

  9. [Severe hemorrhagic gastritis of radiation origin].

    PubMed

    Flobert, C; Cellier, C; Landi, B; Berger, A; Durdux, C; Palazzo, L; Carnot, F; Cugnenc, P H; Barbier, J P

    1998-02-01

    Severe gastric complications due to radiotherapy are uncommon, in particular hemorrhagic gastritis. A high total dose and, above all, high daily fraction appear to be the main risk factors in gastric injuries. A case of hemorrhagic gastritis induced by radiotherapy requesting a total gastrectomy is reported. The patient was treated for a primary gastric non-Hodgkin's lymphoma. Hemorrhagic gastritis occurred despite a low total dose (40 Gy) and 2 Gy daily fractions. Upper gastrointestinal endoscopy and repeated biopsies are usually insufficient to exclude a tumor recurrence. Endoscopic ultrasonography may argue for a recurrence or for radiation lesions. As the conservative treatment is usually ineffective, these gastrointestinal radiation injuries ought to be treated surgically. Besides it allows to ascertain the benign nature of radiation lesions. PMID:9762196

  10. Traumatic intraventricular hemorrhage with a good prognosis.

    PubMed

    Is, Merih; Gezen, Ferruh; Akgul, Mehmet; Dosoglu, Murat

    2011-01-01

    We report a 10-year-old girl with an isolated traumatic intraventricular hemorrhage following a traffic accident, who had a good prognosis. Her neurological examination upon arrival was normal and she had no complaint other than headache and vomiting. Computed tomography on admission showed a hemorrhage in the lateral and fourth ventricles. She had a Glasgow Coma Score of 15, and she was thus given only antiepileptic drugs for prophylaxis and followed. Computed tomography that was repeated 5 days after admission showed no blood and all ventricles were of normal size. There was no vascular pathology on magnetic resonance imaging and magnetic resonance angiography. The patient remains well 5 months after her accident. Intraventricular hemorrhage does not always have a poor prognosis.

  11. Renin responses to hemorrhage in conscious rats

    SciTech Connect

    Roarty, T.P.; Chadwick. K.J.; Raff, H.

    1986-03-01

    The authors investigated the role of beta adrenergic inhibition on the renin response to graded hemorrhage (hem) in conscious rats. Chronic femoral arterial (for measurement of mean arterial pressure - MAP) and venous (for drug infusion) catheters were implanted at least 5 days before experimentation. Hem was administered in < 2 min. 10 rats (CTL) were exposed to a total of 21 episodes of hemorrhage. 13 rats (B-block) were given 1 mg/kg propranolol hydrochloride iv 20 min prior to hem (24 episodes total). Plasma renin activity (PRA) was measured by radioimmunoassay. Pre-hem PRA levels were measured in the first 1 ml of hem blood. Hem resulted in hem volume-dependent decreases in blood pressure and increase-response to hemorrhage.

  12. Renin responses to hemorrhage to conscious rats

    SciTech Connect

    Roarty, T.P.; Chadwick, K.J.; Raff, H.

    1986-03-01

    The authors investigated the role of beta adrenergic inhibition on the renin response to graded hemorrhage (hem) in conscious rats. Chronic femoral arterial (for measurement of mean arterial pressure - MAP) and venous (for drug infusion) catheters were implanted at least 5 days before experimentation. Hem was administered in < 2 min. 10 rats (CTL) were exposed to a total of 21 episodes of hemorrhage. 13 rats (B-block) were given 1 mg/kg propranolol hydrochloride iv 20 min prior to hem (24 episodes total). Plasma renin activity (PRA) was measured by radioimmunoassay. Pre-hem PRA levels were measured in the first 1 ml of hem blood. Hem resulted in hem volume-dependent decreases in blood pressure and increases in PRA. B-block did not significantly alter the mean renin response to hemorrhage.

  13. Primary Medullary Hemorrhage Associated with Hypertension

    PubMed Central

    Kwon, Hyung-Min; Park, Jong-Moo; Lee, Jee-Young

    2005-01-01

    Spontaneous primary medullary hemorrhage is a rare event. A 64-year-old man was admitted for sudden-onset vertigo and vomiting. His clinical features were similar to those of lateral medullary syndrome. The patient had no anticoagulant therapy, vascular malformation, or a caudal extension of a pontine hemorrhage. The patient had multiple hypertensive changes, including retinopathy, left ventricular hypertrophy on electrocardiography, multiple cerebral microbleeds, and small-vessel changes on MRI. T2*-weighted gradient echo MRI performed 3 months prior to admission and contrast-enhanced MRI showed no evidence of vascular malformation. We concluded that the patient had uncontrolled hypertension that may have lead to primary medullary hemorrhage. PMID:20396466

  14. Hereditary Hemorrhagic Telangiectasia with Unusual Associations

    PubMed Central

    Jain, Dheeraj; Ramasamy, Chandramohan

    2015-01-01

    We describe a report of an elderly lady who was hospitalized with progressive worsening of breathlessness and fatigue of one month's duration. Clinical evaluation of the patient revealed hereditary hemorrhagic telangiectasia, interstitial lung disease, pulmonary hypertension without left heart failure, and bilateral gluteal calcinosis cutis. Initially, CREST (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia) syndrome was considered in view of the telangiectasia and calcinosis cutis, but a strong autosomal inheritance pattern and endoscopies (nasal and upper gastrointestinal) favored a diagnosis of hereditary hemorrhagic telangiectasia with rare associations. PMID:26180702

  15. Recovery from Intracranial Hemorrhage Due to Leptospirosis

    PubMed Central

    Babamahmoodi, Farhang; Babamhmoodi, Abdolreza

    2011-01-01

    Intracranial hemorrhage is a rare and fatal presentation of leptospirosis. In this paper we present the case of a 51-year-old male farmer who lives in northern Iran. He came to our hospital with a severe headache. A paraclinical evaluation showed clear signs of thrombocytopenia, and a brain MRI revealed left temporoparietal hemorrhage. Our preliminary diagnosis was Leptospirosis, and after 26 days of hospital care the patient was discharged in good condition. This paper will educationally help physicians in better diagnosis and treatment of leptospirosis. PMID:22013452

  16. Electroretinographic effects of retinal dragging and retinal folds in eyes with familial exudative vitreoretinopathy

    PubMed Central

    Yaguchi, Yukari; Katagiri, Satoshi; Fukushima, Yoko; Yokoi, Tadashi; Nishina, Sachiko; Kondo, Mineo; Azuma, Noriyuki

    2016-01-01

    We evaluated the retinal function of retinal dragging (Rdrag) and radial retinal folds (Rfolds) in eyes with familial exudative vitreoretinopathy (FEVR) using full-field electroretinography (ERG). Seventeen eyes of nine patients with FEVR who had Rdrag or Rfolds were retrospectively studied. Eyes were classified into four groups according to the severity of the retinal alterations: Group 1, without Rdrag or Rfolds (5 eyes); Group 2, with Rdrag (4 eyes); Group 3, with Rfolds (6 eyes); and Group 4, with Rfolds in which all major retinal vessels were involved (2 eyes). The amplitudes of all ERG components and the implicit times of the photopic a- and b-waves and 30-Hz flicker responses were decreased or prolonged as the severity of the retinal alterations increased (P < 0.01). The photopic negative response was most severely affected and nearly undetectable in all eyes in Groups 3 and 4, although the other ERG components were detectable in all eyes in Group 3 and one eye in Group 4. These results suggest the decrease of retinal functions was correlated with the degree of severity of Rdrag and Rfolds in eyes with FEVR. In addition, the function of the retinal ganglion cells appears to be more severely affected compared with the others. PMID:27456314

  17. Increased aqueous flare is associated with thickening of inner retinal layers in eyes with retinitis pigmentosa

    PubMed Central

    Nagasaka, Yosuke; Ito, Yasuki; Ueno, Shinji; Terasaki, Hiroko

    2016-01-01

    Retinitis pigmentosa(RP) is a hereditary retinal disease that causes photoreceptor, outer retinal, degeneration. Although the pathogenesis is still unclear, there have been numerous reports regarding inner retinal changes in RP eyes. The aim of this study is to retrospectively evaluate the changes in the thicknesses of different retinal layers of RP eyes, and its association with aqueous flare, which is used for measuring the intensity of intraocular inflammation. A total of 125 eyes of 64 patients with RP and 13 normal eyes were studied. The thicknesses of total neural retina,nerve fiber layer(NFL),ganglion cell layer(GCL),inner plexiform layer(IPL),inner nuclear layer(INL),outer layers and foveal thickness were measured in the optical coherence tomographic images. Aqueous flare was measured with a laser flare-cell meter. The associations between those parameters, visual acuity and visual field were determined in RP eyes using multivariate analysis. The results of this study showed the significant thickening of NFL, GCL and INL, the significant thinning of outer layers and the association of them with increased aqueous flare, whereas NFL and INL thickening associated with outer retinal thinning. These results can suggest the involvement of intraocular inflammation in the pathogenesis of inner retinal thickening as a secondary change following outer retinal degeneration. PMID:27653207

  18. Submacular hemorrhage in neovascular age-related macular degeneration: A synthesis of the literature.

    PubMed

    Stanescu-Segall, Dinu; Balta, Florian; Jackson, Timothy L

    2016-01-01

    Large submacular hemorrhage, an uncommon manifestation of neovascular age-related macular degeneration, may also occur with idiopathic polypoidal choroidal vasculopathy. Submacular hemorrhage damages photoreceptors owing to iron toxicity, fibrin meshwork contraction, and reduced nutrient flux, with subsequent macular scarring. Clinical and experimental studies support prompt treatment, as tissue damage can occur within 24 hours. Without treatment the natural history is poor, with a mean final visual acuity (VA) of 20/1600. Reported treatments include retinal pigment epithelial patch, macular translocation, pneumatic displacement, intravitreal or subretinal tissue plasminogen activator, intravitreal anti-vascular endothelial growth factor (VEGF) drugs, and combinations thereof. In the absence of comparative studies, we combined eligible studies to assess the VA change before and after each treatment option. The greatest improvement occurred after combined pars plana vitrectomy, subretinal tissue plasminogen activator, intravitreal gas, and anti-vascular endothelial growth factor treatment, with VA improving from 20/1000 to 20/400. The best final VA occurred using combined intravitreal tissue plasminogen activator, gas, and anti-vascular endothelial growth factor therapy, with VA improving from 20/200 to 20/100. Both treatments had an acceptable safety profile, but most studies were small, and larger randomized controlled trials are needed to determine both safety and efficacy.

  19. Toward high-resolution optoelectronic retinal prosthesis

    NASA Astrophysics Data System (ADS)

    Palanker, Daniel; Huie, Philip; Vankov, Alexander; Asher, Alon; Baccus, Steven

    2005-04-01

    It has been already demonstrated that electrical stimulation of retina can produce visual percepts in blind patients suffering from macular degeneration and retinitis pigmentosa. Current retinal implants provide very low resolution (just a few electrodes), while several thousand pixels are required for functional restoration of sight. We present a design of the optoelectronic retinal prosthetic system that can activate a retinal stimulating array with pixel density up to 2,500 pix/mm2 (geometrically corresponding to a visual acuity of 20/80), and allows for natural eye scanning rather than scanning with a head-mounted camera. The system operates similarly to "virtual reality" imaging devices used in military and medical applications. An image from a video camera is projected by a goggle-mounted infrared LED-LCD display onto the retina, activating an array of powered photodiodes in the retinal implant. Such a system provides a broad field of vision by allowing for natural eye scanning. The goggles are transparent to visible light, thus allowing for simultaneous utilization of remaining natural vision along with prosthetic stimulation. Optical control of the implant allows for simple adjustment of image processing algorithms and for learning. A major prerequisite for high resolution stimulation is the proximity of neural cells to the stimulation sites. This can be achieved with sub-retinal implants constructed in a manner that directs migration of retinal cells to target areas. Two basic implant geometries are described: perforated membranes and protruding electrode arrays. Possibility of the tactile neural stimulation is also examined.

  20. [Retinal bleeding and venous stasis in a 10-month-old infant after a fall?].

    PubMed

    Fieß, A; Dithmar, S; Kölb-Keerl, R; Kunze, A; Riße, M; Knuf, M; Bauer, J

    2016-08-01

    This report describes the case of a 10-month-old infant, who was delivered to our hospital by the emergency physician intubated and in an unclear unconscious state. The father reported that the child had fallen from the couch to the ground. The consulted ophthalmologist reported venous stasis in both eyes including intraretinal and preretinal bleeding in all four quadrants, a diffuse vitreous hemorrhage in the right eye and temporal retinal wrinkling in both eyes. Based on these particular clinical findings a shaken baby syndrome was suspected. This report demonstrates the importance of recognizing and correctly interpreting the typical ophthalmological signs of physical child abuse in order to detect and prevent further mistreatment of children; moreover, the increasing importance of photographic documentation and histological work-up of the findings for forensic reasons are emphasized.

  1. [Retinal bleeding and venous stasis in a 10-month-old infant after a fall?].

    PubMed

    Fieß, A; Dithmar, S; Kölb-Keerl, R; Kunze, A; Riße, M; Knuf, M; Bauer, J

    2016-08-01

    This report describes the case of a 10-month-old infant, who was delivered to our hospital by the emergency physician intubated and in an unclear unconscious state. The father reported that the child had fallen from the couch to the ground. The consulted ophthalmologist reported venous stasis in both eyes including intraretinal and preretinal bleeding in all four quadrants, a diffuse vitreous hemorrhage in the right eye and temporal retinal wrinkling in both eyes. Based on these particular clinical findings a shaken baby syndrome was suspected. This report demonstrates the importance of recognizing and correctly interpreting the typical ophthalmological signs of physical child abuse in order to detect and prevent further mistreatment of children; moreover, the increasing importance of photographic documentation and histological work-up of the findings for forensic reasons are emphasized. PMID:26676641

  2. Interventions for asymptomatic retinal breaks and lattice degeneration for preventing retinal detachment

    PubMed Central

    Wilkinson, Charles P

    2015-01-01

    Background Asymptomatic retinal breaks and lattice degeneration are visible lesions that are risk factors for later retinal detachment. Retinal detachments occur when fluid in the vitreous cavity passes through tears or holes in the retina and separates the retina from the underlying retinal pigment epithelium. Creation of an adhesion surrounding retinal breaks and lattice degeneration, with laser photocoagulation or cryotherapy, has been recommended as an effective means of preventing retinal detachment. This therapy is of value in the management of retinal tears associated with the symptoms of flashes and floaters and persistent vitreous traction upon the retina in the region of the retinal break, because such symptomatic retinal tears are associated with a high rate of progression to retinal detachment. Retinal tears and holes unassociated with acute symptoms and lattice degeneration are significantly less likely to be the sites of retinal breaks that are responsible for later retinal detachment. Nevertheless, treatment of these lesions frequently is recommended, in spite of the fact that the effectiveness of this therapy is unproven. Objectives The objective of this review was to assess the effectiveness and safety of techniques used to treat asymptomatic retinal breaks and lattice degeneration for the prevention of retinal detachment. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 2), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to February 2014), EMBASE (January 1980 to February 2014), PubMed (January 1948 to February 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in

  3. Epizootic hemorrhagic disease in Alberta, Canada.

    PubMed

    Pybus, Margo J; Ravi, Madhu; Pollock, Colleen

    2014-07-01

    Epizootic hemorrhagic disease (EHD) virus serotype 2 was identified by reverse-transcription (RT)-PCR in a white-tailed deer (Odocoileus virginianus) found dead in southern Alberta in September 2013. Field observations indicate at least 50 deer, primarily white-tailed deer, and three pronghorn antelope (Antilocapra americana) died during a suspected localized EHD outbreak. PMID:24807363

  4. Severe perinephric hemorrhage after shockwave lithotripsy.

    PubMed

    Antoniou, N K; Karanastasis, D; Stenos, J L

    1995-06-01

    We report a case of a 69-year-old man who, after a second session of shockwave lithotripsy for multiple stones in the right kidney, showed symptoms of severe hemorrhage and flank pain unresponsive to analgesics, with the gradual development of extensive and serious perinephric hematoma. The bleeding necessitated nephrectomy. Unrecognized chronic pyelonephritis may have been a predisposing factor.

  5. Uterine artery embolization for primary postpartum hemorrhage

    PubMed Central

    Kim, Tae-Hee; Lee, Hae-Hyeog; Kim, Jun-Mo; Ryu, Ae-Li; Chung, Soo-Ho; Seok Lee, Woo

    2013-01-01

    Background: Postpartum hemorrhage is the leading cause of severe maternal morbidity and death. A prompt management of uterine artery embolization (UAE) is important for a good outcome. UAE is generally accepted to be a safe and reliable procedure. Objective: To estimate critical patient characteristics influencing the success of UAE for the treatment of emergent primary postpartum hemorrhage. Materials and Methods: This was a cross sectional study that reviewed 121 patients who were diagnosed primary postpartum hemorrhage between February 2002 and December 2009 at a tertiary treatment center among 4,022 deliveries. We evaluated patient clinical characteristics associated with a successful surgical outcome of UAE. Results: The success rate for UAE was 96%. For two cases, UAE complication was associated with fever (>38.5oC). Five patients had problems that required admission to the intensive care unit (ICU). Conclusion: To increase the surgical success rate and lower the number of ICU admissions, the decision to treat primary postpartum hemorrhage using UAE should be based on individual patient clinical findings under the direction of obstetrics staff and an interventional radiologist. PMID:24639786

  6. How I treat patients with massive hemorrhage.

    PubMed

    Johansson, Pär I; Stensballe, Jakob; Oliveri, Roberto; Wade, Charles E; Ostrowski, Sisse R; Holcomb, John B

    2014-11-13

    Massive hemorrhage is associated with coagulopathy and high mortality. The transfusion guidelines up to 2006 recommended that resuscitation of massive hemorrhage should occur in successive steps using crystalloids, colloids, and red blood cells (RBCs) in the early phase and plasma and platelets in the late phase. With the introduction of the cell-based model of hemostasis in the mid-1990s, our understanding of the hemostatic process and of coagulopathy has improved. This has contributed to a change in resuscitation strategy and transfusion therapy of massive hemorrhage along with an acceptance of the adequacy of whole blood hemostatic tests to monitor these patients. Thus, in 2005, a strategy aiming at avoiding coagulopathy by proactive resuscitation with blood products in a balanced ratio of RBC:plasma:platelets was introduced, and this has been reported to be associated with reduced mortality in observational studies. Concurrently, whole blood viscoelastic hemostatic assays have gained acceptance by allowing a rapid and timely identification of coagulopathy along with enabling an individualized, goal-directed transfusion therapy. These strategies joined together seem beneficial for patient outcome, although final evidence on outcome from randomized controlled trials are lacking. We present how we in Copenhagen and Houston, today, manage patients with massive hemorrhage.

  7. Subperiosteal orbital hemorrhage following self-strangulation.

    PubMed

    Knox Cartwright, Nathaniel E; Hussin, Hussin M; Biswas, Suman; Majid, Mohammed A; Potts, Mike J; Kabala, Julian; Mayer, Eric J

    2007-01-01

    Subperiosteal orbital hematomas are uncommon. The delayed presentation of such an event is described in an anticoagulated patient who attempted self-strangulation. Despite the initial presence of a relative afferent pupillary defect, excellent visual recovery occurred, demonstrating the importance of prompt recognition and treatment. The causes, mechanism of visual loss, radiographic diagnosis, and treatment of subperiosteal hemorrhages are discussed.

  8. Massive obstetric hemorrhage: Current approach to management.

    PubMed

    Guasch, E; Gilsanz, F

    2016-01-01

    Massive obstetric hemorrhage is a major cause of maternal mortality and morbidity worldwide. It is defined (among others) as the loss of>2,500ml of blood, and is associated to a need for admission to critical care and/or hysterectomy. The relative hemodilution and high cardiac output found in normal pregnancy allows substantial bleeding before a drop in hemoglobin and/or hematocrit can be identified. Some comorbidities associated with pregnancy can contribute to the occurrence of catastrophic bleeding with consumption coagulopathy, which makes the situation even worse. Optimization, preparation, rational use of resources and protocolization of actions are often useful to improve outcomes in patients with postpartum hemorrhage. Using massive obstetric hemorrhage protocols is useful for facilitating rapid transfusion if needed, and can also be cost-effective. If hypofibrinogenemia during the bleeding episode is identified, early fibrinogen administration can be very useful. Other coagulation factors in addition to fibrinogen may be necessary during postpartum hemorrhage replacement measures in order to effectively correct coagulopathy. A hysterectomy is recommended if the medical and surgical measures prove ineffective. PMID:27184441

  9. Unilateral adrenal hemorrhagic infarction in essential thrombocythemia.

    PubMed

    Burnet, G; Lambert, M; Annet, L; Lefebvre, C

    2015-12-01

    Adrenal hemorrhage is a rare disease associated with various conditions. We report a case of a 68-year-old woman with abdominal and back pain. The diagnostic work-up showed a left adrenal gland infarction associated with essential thrombocythemia. Treatment consisted in painkillers and treating the underlying condition in order to prevent further thrombotic events.

  10. Animal Models for Viral Hemorrhagic Fever.

    PubMed

    Falzarano, Darryl; Bente, Dennis A

    2014-04-01

    Viral hemorrhagic fever can be caused by one of a diverse group of viruses that come from four different families of RNA viruses. Disease severity can vary from mild self-limiting febrile illness to severe disease characterized by high fever, high-level viremia, increased vascular permeability that can progress to shock, multi-organ failure, and death. Despite the urgent need, effective treatments and preventative vaccines are currently lacking for the majority of these viruses. A number of factors preclude the effective study of these diseases in humans including the high virulence of the agents involved, the sporadic nature of outbreaks of these viruses which are typically in geographically isolated areas with underserviced diagnostic capabilities, and the requirements for high level bio-containment. As a result, animal models that accurately mimic human disease are essential for advancing our understanding of the pathogenesis of viral hemorrhagic fevers. Moreover, animal models for viral hemorrhagic fevers are necessary to test vaccines and therapeutic intervention strategies. Here, we present an overview of the animal models that have been established for each of the hemorrhagic fever viruses and identify which aspects of human disease are modeled. Furthermore, we discuss how experimental design considerations, such as choice of species and virus strain as well as route and dose of inoculation, have an influence on animal model development. We also bring attention to some of the pitfalls that need to be avoided when extrapolating results from animal models. This article is protected by copyright. All rights reserved.

  11. Pathologic pulmonary changes in hemorrhagic shock.

    PubMed Central

    Garvey, J W; Hagstrom, J W; Veith, F J

    1975-01-01

    Fifty-seven dogs were subjected to hemorrhagic hypotension by a variety of protocols. Histologic pulmonary changes were studied using the light microscope. Of these 57 dogs, 21 had no demonstrable lesions, 8 had minimal changes, and 28 had moderate or severe lesions, all of a focal nature. No correlation was found between the presence of lesions and mean systemic arterial pressure during shock, the udration of the hemorrhagic period, the fate of the animal, preoperative hematocrits and blood volumes, mean postreinfusion arterial pressure, whether the animals were mongrels or purebred beagles, whether they were awake or sedated, whether they breathed spontaneously or were artifically ventilated, whether they had undergone previous splenectomy or not, whether hilar stripping was performed or not, and finally, whether blood was reinfused after hemorrhage or not. Thus we conclude that multiple factors may exert a harmful effect on the lung in hemorrhagic shock, and that shock probably makes the lungs more vulnerable to other injurious agents rather than there being one single pathogenetic mechanism for the pulmonary damage. The term "adult respiratory distress syndrome" rather than "shock lung" is best used for the human clinical entity since it implies a complex ettiology rather than a discrete pulmonary lesion produced by a single pathogenetic mechanism. PMID:1138638

  12. [Hemorrhagic complications of anti-vitamin K].

    PubMed

    Al-Hajje, A; Calop, N; Bosson, J L; Calop, J; Allenet, B

    2009-03-01

    Adverse events related to oral anticoagulants represent a major public health problem. Hemorrhagic episodes are the most frequent complications and can be life-threatening. A 10 month prospective survey on all cases treated with anti-vitamin K (AVK), and admitted to emergency room of CHU Grenoble, was conducted to identify the hemorrhagic adverse drug events (HADE). The evaluation support was a directive questionnaire and consisted of 3 parts: patient characteristics, patient's medicated treatment and the hemorrhagic event. 216 patients treated with AVK were identified and 68 of them presented a hemorrhagic adverse drug event. 60 patients older than 65 years out of 158, presented HADE (38%); versus 8 patients < or = 65 years out of 58 (RR = 2.75; p = 0.0007). Among the patients who have their INR > or = 5, 79% developed HADE versus 16% in the group who had their INR < 5 (< 0.0001). In the group of patients who had a change in drug therapy within the 7 days preceding their admission, 47% developed HADE versus 25% of patients whose treatment was not modified: Anti-microbial agents were the drug most frequently involved. The patient's knowledge of INR value and signs of excess AVK were significant. Concerning missed dose, 48 patients declared taking the missed dose with the next dose or when they remembered: 35% of them developed HADE (p = 0.49).

  13. Amyloidosis in Retinal Neurodegenerative Diseases.

    PubMed

    Masuzzo, Ambra; Dinet, Virginie; Cavanagh, Chelsea; Mascarelli, Frederic; Krantic, Slavica

    2016-01-01

    As a part of the central nervous system, the retina may reflect both physiological processes and abnormalities related to pathologies that affect the brain. Amyloidosis due to the accumulation of amyloid-beta (Aβ) was initially regarded as a specific and exclusive characteristic of neurodegenerative alterations seen in the brain of Alzheimer's disease (AD) patients. More recently, it was discovered that amyloidosis-related alterations, similar to those seen in the brain of Alzheimer's patients, also occur in the retina. Remarkably, these alterations were identified not only in primary retinal pathologies, such as age-related macular degeneration (AMD) and glaucoma, but also in the retinas of Alzheimer's patients. In this review, we first briefly discuss the biogenesis of Aβ, a peptide involved in amyloidosis. We then discuss some pathological aspects (synaptic dysfunction, mitochondrial failure, glial activation, and vascular abnormalities) related to the neurotoxic effects of Aβ. We finally highlight common features shared by AD, AMD, and glaucoma in the context of Aβ amyloidosis and further discuss why the retina, due to the transparency of the eye, can be considered as a "window" to the brain. PMID:27551275

  14. Amyloidosis in Retinal Neurodegenerative Diseases

    PubMed Central

    Masuzzo, Ambra; Dinet, Virginie; Cavanagh, Chelsea; Mascarelli, Frederic; Krantic, Slavica

    2016-01-01

    As a part of the central nervous system, the retina may reflect both physiological processes and abnormalities related to pathologies that affect the brain. Amyloidosis due to the accumulation of amyloid-beta (Aβ) was initially regarded as a specific and exclusive characteristic of neurodegenerative alterations seen in the brain of Alzheimer’s disease (AD) patients. More recently, it was discovered that amyloidosis-related alterations, similar to those seen in the brain of Alzheimer’s patients, also occur in the retina. Remarkably, these alterations were identified not only in primary retinal pathologies, such as age-related macular degeneration (AMD) and glaucoma, but also in the retinas of Alzheimer’s patients. In this review, we first briefly discuss the biogenesis of Aβ, a peptide involved in amyloidosis. We then discuss some pathological aspects (synaptic dysfunction, mitochondrial failure, glial activation, and vascular abnormalities) related to the neurotoxic effects of Aβ. We finally highlight common features shared by AD, AMD, and glaucoma in the context of Aβ amyloidosis and further discuss why the retina, due to the transparency of the eye, can be considered as a “window” to the brain. PMID:27551275

  15. Multi-MHz retinal OCT

    PubMed Central

    Klein, Thomas; Wieser, Wolfgang; Reznicek, Lukas; Neubauer, Aljoscha; Kampik, Anselm; Huber, Robert

    2013-01-01

    We analyze the benefits and problems of in vivo optical coherence tomography (OCT) imaging of the human retina at A-scan rates in excess of 1 MHz, using a 1050 nm Fourier-domain mode-locked (FDML) laser. Different scanning strategies enabled by MHz OCT line rates are investigated, and a simple multi-volume data processing approach is presented. In-vivo OCT of the human ocular fundus is performed at different axial scan rates of up to 6.7 MHz. High quality non-mydriatic retinal imaging over an ultra-wide field is achieved by a combination of several key improvements compared to previous setups. For the FDML laser, long coherence lengths and 72 nm wavelength tuning range are achieved using a chirped fiber Bragg grating in a laser cavity at 419.1 kHz fundamental tuning rate. Very large data sets can be acquired with sustained data transfer from the data acquisition card to host computer memory, enabling high-quality averaging of many frames and of multiple aligned data sets. Three imaging modes are investigated: Alignment and averaging of 24 data sets at 1.68 MHz axial line rate, ultra-dense transverse sampling at 3.35 MHz line rate, and dual-beam imaging with two laser spots on the retina at an effective line rate of 6.7 MHz. PMID:24156052

  16. Intrinsically photosensitive retinal ganglion cells.

    PubMed

    Do, Michael Tri Hoang; Yau, King-Wai

    2010-10-01

    Life on earth is subject to alternating cycles of day and night imposed by the rotation of the earth. Consequently, living things have evolved photodetective systems to synchronize their physiology and behavior with the external light-dark cycle. This form of photodetection is unlike the familiar "image vision," in that the basic information is light or darkness over time, independent of spatial patterns. "Nonimage" vision is probably far more ancient than image vision and is widespread in living species. For mammals, it has long been assumed that the photoreceptors for nonimage vision are also the textbook rods and cones. However, recent years have witnessed the discovery of a small population of retinal ganglion cells in the mammalian eye that express a unique visual pigment called melanopsin. These ganglion cells are intrinsically photosensitive and drive a variety of nonimage visual functions. In addition to being photoreceptors themselves, they also constitute the major conduit for rod and cone signals to the brain for nonimage visual functions such as circadian photoentrainment and the pupillary light reflex. Here we review what is known about these novel mammalian photoreceptors. PMID:20959623

  17. Evaluation and management of pediatric rhegmatogenous retinal detachment

    PubMed Central

    Wenick, Adam S.; Barañano, David E.

    2012-01-01

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

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

    NASA Astrophysics Data System (ADS)

    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.

  19. Preclinical Models to Investigate Retinal Ischemia: Advances and Drawbacks

    PubMed Central

    Minhas, Gillipsie; Morishita, Ryuichi; Anand, Akshay

    2012-01-01

    Retinal ischemia is a major cause of blindness worldwide. It is associated with various disorders such as diabetic retinopathy, glaucoma, optic neuropathies, stroke, and other retinopathies. Retinal ischemia is a clinical condition that occurs due to lack of appropriate supply of blood to the retina. As the retina has a higher metabolic demand, any hindrance in the blood supply to it can lead to decreased supply of oxygen, thus causing retinal ischemia. The pathology of retinal ischemia is still not clearly known. To get a better insight into the pathophysiology of retinal ischemia, the role of animal models is indispensable. The standard treatment care for retinal ischemia has limited potential. Transplantation of stem cells provide neuroprotection and to replenish damaged cells is an emerging therapeutic approach to treat retinal ischemia. In this review we provide an overview of major animal models of retinal ischemia along with the current and preclinical treatments in use. PMID:22593752

  20. Unraveling the distinctive features of hemorrhagic and non-hemorrhagic snake venom metalloproteinases using molecular simulations.

    PubMed

    de Souza, Raoni Almeida; Díaz, Natalia; Nagem, Ronaldo Alves Pinto; Ferreira, Rafaela Salgado; Suárez, Dimas

    2016-01-01

    Snake venom metalloproteinases are important toxins that play fundamental roles during envenomation. They share a structurally similar catalytic domain, but with diverse hemorrhagic capabilities. To understand the structural basis for this difference, we build and compare two dynamical models, one for the hemorrhagic atroxlysin-I from Bothrops atrox and the other for the non-hemorraghic leucurolysin-a from Bothrops leucurus. The analysis of the extended molecular dynamics simulations shows some changes in the local structure, flexibility and surface determinants that can contribute to explain the different hemorrhagic activity of the two enzymes. In agreement with previous results, the long Ω-loop (from residue 149 to 177) has a larger mobility in the hemorrhagic protein. In addition, we find some potentially-relevant differences at the base of the S1' pocket, what may be interesting for the structure-based design of new anti-venom agents. However, the sharpest differences in the computational models of atroxlysin-I and leucurolysin-a are observed in the surface electrostatic potential around the active site region, suggesting thus that the hemorrhagic versus non-hemorrhagic activity is probably determined by protein surface determinants. PMID:26676823

  1. Blood-filled cerebrospinal fluid-enhanced pericyte microvasculature contraction in rat retina: A novel in vitro study of subarachnoid hemorrhage

    PubMed Central

    Liu, Zhi; Li, Qiang; Cui, Gaoyu; Zhu, Gang; Tang, Weihua; Zhao, Hengli; Zhang, John H.; Chen, Yujie; Feng, Hua

    2016-01-01

    Previously, it was widely accepted that the delayed ischemic injury and poor clinical outcome following subarachnoid hemorrhage (SAH) was caused by cerebral vasospasm. This classical theory was challenged by a clazosentan clinical trial, which failed to improve patient outcome, despite reversing angiographic vasospasm. One possible explanation for the results of this trial is the changes in microcirculation following SAH, particularly in pericytes, which are the primary cell type controlling microcirculation in the brain parenchyma. However, as a result of technical limitations and the lack of suitable models, there was no direct evidence of microvessel dysfunction following SAH. In the present study, whole-mount retinal microvasculature has been introduced to study microcirculation in the brain following experimental SAH in vitro. Artificial blood-filled cerebrospinal fluid (BSCF) was applied to the retinal microvasculature to test the hypothesis that the presence of subarachnoid blood affects the contractile properties of the pericytes containing cerebral microcirculation during the early phase of SAH. It was observed that BCSF induced retina microvessel contraction and that this contraction could be resolved by BCSF wash-out. Furthermore, BCSF application accelerated pericyte-populated collagen gel contraction and increased the expression of α-smooth muscle actin. In addition, BCSF induced an influx of calcium in cultured retinal pericytes. In conclusion, the present study demonstrates increased contractility of retinal microvessels and pericytes in the presence of BCSF in vitro. These findings suggest that pericyte contraction and microvascular dysfunction is induced following SAH, which could lead to greater susceptibility to SAH-induced ischemia.

  2. Therapeutic Hypothermia and the Risk of Hemorrhage

    PubMed Central

    Wang, Chih-Hung; Chen, Nai-Chuan; Tsai, Min-Shan; Yu, Ping-Hsun; Wang, An-Yi; Chang, Wei-Tien; Huang, Chien-Hua; Chen, Wen-Jone

    2015-01-01

    Abstract Current guidelines recommend a period of moderate therapeutic hypothermia (TH) for comatose patients after cardiac arrest to improve clinical outcomes. However, in-vitro studies have reported platelet dysfunction, thrombocytopenia, and coagulopathy, results that might discourage clinicians from applying TH in clinical practice. We aimed to quantify the risks of hemorrhage observed in clinical studies. Medline and Embase were searched from inception to October 2015. Randomized controlled trials (RCTs) comparing patients undergoing TH with controls were selected, irrespective of the indications for TH. There were no restrictions for language, population, or publication year. Data on study characteristics, which included patients, details of intervention, and outcome measures, were extracted. Forty-three trials that included 7528 patients were identified from 2692 potentially relevant references. Any hemorrhage was designated as the primary outcome and was reported in 28 studies. The pooled results showed no significant increase in hemorrhage risk associated with TH (risk difference [RD] 0.005; 95% confidence interval [CI] −0.001–0.011; I2, 0%). Among secondary outcomes, patients undergoing TH were found to have increased risk of thrombocytopenia (RD 0.109; 95% CI 0.038–0.179; I2 57.3%) and transfusion requirements (RD 0.021; 95% CI 0.003–0.040; I2 0%). The meta-regression analysis indicated that prolonged duration of cooling may be associated with increased risk of hemorrhage. TH was not associated with increased risk of hemorrhage despite the increased risk of thrombocytopenia and transfusion requirements. Clinicians should cautiously assess each patient's risk-benefit profile before applying TH. PMID:26632746

  3. Retinal Conformation Changes Rhodopsin's Dynamic Ensemble.

    PubMed

    Leioatts, Nicholas; Romo, Tod D; Danial, Shairy Azmy; Grossfield, Alan

    2015-08-01

    G protein-coupled receptors are vital membrane proteins that allosterically transduce biomolecular signals across the cell membrane. However, the process by which ligand binding induces protein conformation changes is not well understood biophysically. Rhodopsin, the mammalian dim-light receptor, is a unique test case for understanding these processes because of its switch-like activity; the ligand, retinal, is bound throughout the activation cycle, switching from inverse agonist to agonist after absorbing a photon. By contrast, the ligand-free opsin is outside the activation cycle and may behave differently. We find that retinal influences rhodopsin dynamics using an ensemble of all-atom molecular dynamics simulations that in aggregate contain 100 μs of sampling. Active retinal destabilizes the inactive state of the receptor, whereas the active ensemble was more structurally homogenous. By contrast, simulations of an active-like receptor without retinal present were much more heterogeneous than those containing retinal. These results suggest allosteric processes are more complicated than a ligand inducing protein conformational changes or simply capturing a shifted ensemble as outlined in classic models of allostery.

  4. Dynamics of retinal photocoagulation and rupture

    NASA Astrophysics Data System (ADS)

    Sramek, Christopher; Paulus, Yannis; Nomoto, Hiroyuki; Huie, Phil; Brown, Jefferson; Palanker, Daniel

    2009-05-01

    In laser retinal photocoagulation, short (<20 ms) pulses have been found to reduce thermal damage to the inner retina, decrease treatment time, and minimize pain. However, the safe therapeutic window (defined as the ratio of power for producing a rupture to that of mild coagulation) decreases with shorter exposures. To quantify the extent of retinal heating and maximize the therapeutic window, a computational model of millisecond retinal photocoagulation and rupture was developed. Optical attenuation of 532-nm laser light in ocular tissues was measured, including retinal pigment epithelial (RPE) pigmentation and cell-size variability. Threshold powers for vaporization and RPE damage were measured with pulse durations ranging from 1 to 200 ms. A finite element model of retinal heating inferred that vaporization (rupture) takes place at 180-190°C. RPE damage was accurately described by the Arrhenius model with activation energy of 340 kJ/mol. Computed photocoagulation lesion width increased logarithmically with pulse duration, in agreement with histological findings. The model will allow for the optimization of beam parameters to increase the width of the therapeutic window for short exposures.

  5. Advances in retinal ganglion cell imaging

    PubMed Central

    Balendra, S I; Normando, E M; Bloom, P A; Cordeiro, M F

    2015-01-01

    Glaucoma is one of the leading causes of blindness worldwide and will affect 79.6 million people worldwide by 2020. It is caused by the progressive loss of retinal ganglion cells (RGCs), predominantly via apoptosis, within the retinal nerve fibre layer and the corresponding loss of axons of the optic nerve head. One of its most devastating features is its late diagnosis and the resulting irreversible visual loss that is often predictable. Current diagnostic tools require significant RGC or functional visual field loss before the threshold for detection of glaucoma may be reached. To propel the efficacy of therapeutics in glaucoma, an earlier diagnostic tool is required. Recent advances in retinal imaging, including optical coherence tomography, confocal scanning laser ophthalmoscopy, and adaptive optics, have propelled both glaucoma research and clinical diagnostics and therapeutics. However, an ideal imaging technique to diagnose and monitor glaucoma would image RGCs non-invasively with high specificity and sensitivity in vivo. It may confirm the presence of healthy RGCs, such as in transgenic models or retrograde labelling, or detect subtle changes in the number of unhealthy or apoptotic RGCs, such as detection of apoptosing retinal cells (DARC). Although many of these advances have not yet been introduced to the clinical arena, their successes in animal studies are enthralling. This review will illustrate the challenges of imaging RGCs, the main retinal imaging modalities, the in vivo techniques to augment these as specific RGC-imaging tools and their potential for translation to the glaucoma clinic. PMID:26293138

  6. Protocadherin-17 Function in Zebrafish Retinal Development

    PubMed Central

    Chen, Yun; Londraville, Richard; Brickner, Sarah; El-Shaar, Lana; Fankhauser, Kelsee; Dearth, Cassandra; Fulton, Leah; Sochacka, Alicja; Bhattarai, Sunil; Marrs, James A.; Liu, Qin

    2012-01-01

    Cadherin cell adhesion molecules play crucial roles in vertebrate development including the development of the retina. Most studies have focused on examining functions of classic cadherins (e.g. N-cadherin) in retinal development. There is little information on the function of protocadherins in the development of the vertebrate visual system. We previously showed that protocadherin-17 mRNA was expressed in developing zebrafish retina during critical stages of the retinal development. To gain insight into protocadherin-17 function in the formation of the retina, we analyzed eye development and differentiation of retinal cells in zebrafish embryos injected with protocadherin-17 specific antisense morpholino oligonucleotides (MOs). Protocadherin-17 knockdown embryos (pcdh17 morphants) had significantly reduced eyes due mainly to decreased cell proliferation. Differentiation of several retinal cell types (e.g. retinal ganglion cells) was also disrupted in the pcdh17 morphants. Phenotypic rescue was achieved by injection of protocadherin-17 mRNA. Injection of a vivo-protocadherin-17 MO into one eye of embryonic zebrafish resulted in similar eye defects. Our results suggest that protocadherin-17 plays an important role in the normal formation of the zebrafish retina. PMID:22927092

  7. [Genetic diagnostic testing in inherited retinal dystrophies].

    PubMed

    Kohl, S; Biskup, S

    2013-03-01

    Inherited retinal dystrophies are clinically and genetically highly heterogeneous. They can be divided according to the clinical phenotype and course of the disease, as well as the underlying mode of inheritance. Isolated retinal dystrophies (i.e., retinitis pigmentosa, Leber's congenital amaurosis, cone and cone-rod dystrophy, macular dystrophy, achromatopsia, congenital stationary nightblindness) and syndromal forms (i.e., Usher syndrome, Bardet-Biedl syndrome) can be differentiated. To date almost 180 genes and thousands of distinct mutations have been identified that are responsible for the different forms of these blinding illnesses. Until recently, there was no adequate diagnostic genetic testing available. With the development of the next generation sequencing technologies, a comprehensive genetic screening analysis for all known genes for inherited retinal dystrophies has been established at reasonable costs and in appropriate turn-around times. Depending on the primary clinical diagnosis and the presumed mode of inheritance, different diagnostic panels can be chosen for genetic testing. Statistics show that in 55-80 % of the cases the genetic defect of the inherited retinal dystrophy can be identified with this approach, depending on the initial clinical diagnosis. The aim of any genetic diagnostics is to define the genetic cause of a given illness within the affected patient and family and thereby i) confirm the clinical diagnosis, ii) provide targeted genetic testing in family members, iii) enable therapeutic intervention, iv) give a prognosis on disease course and progression and v) in the long run provide the basis for novel therapeutic approaches and personalised medicine.

  8. RETINAL ANGIOMATOUS PROLIFERATION CASE REPORT.

    PubMed

    Olaru, Andrei; Olaru, Denissa-Greta; Nicolcescu, Andreea; Olaru, Cristian; Popescu, Mihaela; Deca, Andreea-Gabriela; Mocanu, Carmen

    2015-01-01

    The diagnosis of RAP is similar with the diagnosis of the AMD, but PED, exudate and superficial hemorrhages are more common in RAP. A 75-year-old male presented himself at the Ophthalmology Department of the Emergency County Hospital in Craiova in January 2015, with a 4 months history of vision loss. In his right eye the visual acuity was 4/50 eye non-optical correctable and 5/5 with optical correction in the left eye. According to the FA and OCT that were performed in both eyes, in the right eye was found intraretinal neovascularization and sub and intraretinal fluid. A normal aspect was found in the left eye. After the investigations we decided to start the treatment consisting in one single intravitreal injection with Triamcinolone Acetonide (IVTA) in the right eye. The VA improved 1 week after the treatment from 4/50 to 5/30. In comparison with the improved VA, the macular edema gradually resorbed 1 month after the IVTA injection. In spite of the late presentation of the patient in the Ophthalmology Department, the VA and OCT outcome after a single dose of IVTA injection was very good. PMID:26978886

  9. Spontaneous retroperitoneal hemorrhage secondary to subcapsular renal hematoma: MRI findings.

    PubMed

    Balci, N C; Sirvanci, M; Tüfek, I; Onat, L; Duran, C

    2001-10-01

    Spontaneous retroperitoneal hemorrhage is a rare intraabdominal bleeding. In this report we present a case of a nontraumatic retroperitoneal hemorrhage secondary to spontaneous subcapsular renal hematoma. A 54-year-old patient who was under warfarin therapy, developed subcapsular right renal hematoma. Subcapsular and retroperitoneal hemorrhage were low signal on T1- and T2-weighted images consistent with acute stage of blood. The source of subcapsular hematoma was shown to be the rupture of hemorrhagic renal cyst on MRI. Extension of hemorrhage into the retroperitoneal space anterior to right psoas muscle was also successfully shown on MRI. Patient underwent nephrectomy and retroperitoneal blood was evacuated.

  10. Extensive intraalveolar pulmonary hemorrhage in infants dying after surfactant therapy.

    PubMed

    Pappin, A; Shenker, N; Hack, M; Redline, R W

    1994-04-01

    To assess the possible relationship between exogenous surfactant therapy and pulmonary hemorrhage in premature infants, we compared autopsy findings in 15 infants treated with exogenous surfactant and in 29 who died before the introduction of surfactant therapy. Infants who met the following criteria were included: birth weight 501 to 1500 gm, survival 4 hours to 7 days, and no congenital anomalies. Average birth weight, gestational age, and age at death were equivalent for the two groups. High rates of pulmonary hemorrhage were present in both groups (treated 80% vs untreated 83%). The untreated group had higher incidences of interstitial hemorrhage and lung hematomas and significantly more large interstitial hemorrhages: 31% untreated versus 0% treated (p < 0.05). The overall rate of intraalveolar hemorrhage was similar in the two groups, but surfactant-treated infants were more likely to have extensive intraalveolar hemorrhage: 53% versus 14% (p < 0.05). Most surfactant-treated infants who survived more than 24 hours had extensive intraalveolar hemorrhage (8/9). Patients who had extensive intraalveolar hemorrhage, with or without prior surfactant therapy, frequently had clinically significant pulmonary hemorrhage (7/12). These findings indicate that infants who die after surfactant therapy have higher rates of a specific type of pulmonary hemorrhage--extensive intraalveolar hemorrhage.

  11. Thermoregulatory set point decreases after hemorrhage in rats.

    PubMed

    Brown, Justin W; Whitehurst, Marvin E; Gordon, Christopher J; Carroll, Robert G

    2005-03-01

    Hemorrhage in rats causes a drop in body core temperature that is proportional to the hemorrhage volume. We tested the hypothesis that the hemorrhagic hypothermia is due to a downward shift in the thermoregulatory set point. If so, rats subjected to hemorrhage would prefer a cooler ambient temperature to enhance heat loss during the posthemorrhage period. Male Sprague-Dawley rats were fitted with carotid arterial catheters and biotelemetry temperature probes. Two days later, rats were placed in a temperature gradient chamber that allowed the rat to move between ambient temperatures of 15 degrees C to 40 degrees C. Rat location within the gradient was recorded as the selected ambient temperature. After 48 h, a 24 mL/kg hemorrhage was induced via the carotid cannula followed by a 24-h recovery period in the gradient. Body core and selected ambient temperatures significantly decreased after hemorrhage. Within 50 min, selected ambient temperature decreased by 11 degrees C, and returned to normal 100 min after hemorrhage. Within 80 min after hemorrhage, core temperature decreased by 2.3 degrees C, and returned to normal by 8 h after hemorrhage. Expanded analysis of the first hour after hemorrhage showed that reduction in selected ambient temperature preceded the drop in body core temperature. Importantly, the decrease in selected ambient temperature persisted even during the peak decrease in body core temperature. These results indicate that a decrease in thermoregulatory set point contributes to the drop in body core temperature after hemorrhage. PMID:15718921

  12. Inferior retinal light exposure is more effective than superior retinal exposure in suppressing melatonin in humans

    NASA Technical Reports Server (NTRS)

    Glickman, Gena; Hanifin, John P.; Rollag, Mark D.; Wang, Jenny; Cooper, Howard; Brainard, George C.

    2003-01-01

    Illumination of different areas of the human retina elicits differences in acute light-induced suppression of melatonin. The aim of this study was to compare changes in plasma melatonin levels when light exposures of equal illuminance and equal photon dose were administered to superior, inferior, and full retinal fields. Nine healthy subjects participated in the study. Plexiglass eye shields were modified to permit selective exposure of the superior and inferior halves of the retinas of each subject. The Humphrey Visual Field Analyzer was used both to confirm intact full visual fields and to quantify exposure of upper and lower visual fields. On study nights, eyes were dilated, and subjects were exposed to patternless white light for 90 min between 0200 and 0330 under five conditions: (1) full retinal exposure at 200 lux, (2) full retinal exposure at 100 lux, (3) inferior retinal exposure at 200 lux, (4) superior retinal exposure at 200 lux, and (5) a dark-exposed control. Plasma melatonin levels were determined by radioimmunoassay. ANOVA demonstrated a significant effect of exposure condition (F = 5.91, p < 0.005). Post hoc Fisher PLSD tests showed significant (p < 0.05) melatonin suppression of both full retinal exposures as well as the inferior retinal exposure; however, superior retinal exposure was significantly less effective in suppressing melatonin. Furthermore, suppression with superior retinal exposure was not significantly different from that of the dark control condition. The results indicate that the inferior retina contributes more to the light-induced suppression of melatonin than the superior retina at the photon dosages tested in this study. Findings suggest a greater sensitivity or denser distribution of photoreceptors in the inferior retina are involved in light detection for the retinohypothalamic tract of humans.

  13. Low Vision Rehabilitation of Retinitis Pigmentosa. Practice Report

    ERIC Educational Resources Information Center

    Rundquist, John

    2004-01-01

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

  14. Retinas in a Dish Peek into Inherited Retinal Degeneration.

    PubMed

    Duong, Thu T; Vasireddy, Vidyullatha; Mills, Jason A; Bennett, Jean

    2016-06-01

    Human retinal degeneration can cause blindness, and the lack of relevant model systems has made identifying underlying mechanisms challenging. Parfitt et al. (2016) generate three-dimensional retinal tissue from patient-derived induced pluripotent stem cells to identify how CEP290 mutations cause retinal degeneration, and show an antisense approach can correct disease-associated phenotypes. PMID:27257755

  15. Angiographic findings in 2 children with cerebral paragonimiasis with hemorrhage.

    PubMed

    Chen, Zhi; Chen, Jingyu; Miao, Hongpin; Li, Fei; Feng, Hua; Zhu, Gang

    2013-05-01

    Hemorrhagic events associated with cerebral paragonimiasis are not rare, especially in children and adolescents; however, angiographic evidence of cerebrovascular involvement has not been reported. The authors describe angiographic abnormalities of the cerebral arteries seen in 2 children in whom cerebral paragonimiasis was associated with hemorrhagic stroke. The patients presented with acute intracerebral and subarachnoid hemorrhage. Angiography revealed a beaded appearance and long segmental narrowing of arteries, consistent with arteritis. In both patients, involved vessels were seen in the area of the hemorrhage. The vascular changes and the hemorrhage, together with new lesions that developed close to the hemorrhage and improved after praziquantel treatment, were attributed to paragonimiasis. Further study of the frequency and mechanism of hemorrhagic cerebrovascular complications associated with cerebral paragonimiasis is needed.

  16. Characterization of hemorrhages in the tenderloins of slaughter pigs.

    PubMed

    Dich-Jørgensen, Kristine; McEvoy, Fintan J; Larsen, Helle Daugaard; Leifsson, Páll S; Jensen, Henrik Elvang

    2016-11-01

    Muscle hemorrhages are regularly observed in especially the tip of the tenderloin muscles of slaughter pigs. In order to characterize the hemorrhages, a macro- and microscopic examination of tenderloins with (n=5) and without (n=4) hemorrhages and the associated vertebral column was carried out. Furthermore, all columns were radiographed and two were CT scanned. Histologically, the muscle hemorrhages contained cells from bone marrow and growth line cartilage. Ventral epiphysiolysis in either the cranial or caudal epiphysis of the first lumbar vertebrae (L1) in 8 out of the 9 vertebral columns was present. In the 5 cases with tenderloin hemorrhage, similar hemorrhage with growth line cartilage was found within the fracture of the epiphysis. The hemorrhages develop secondarily to epiphysiolysis in the lumbar vertebrae, where the tenderloin attaches to the spine. The lesions probably develop around the time of stunning. PMID:27372280

  17. Argon laser panretinal photocoagulation in ischemic central retinal vein occlusion. A 10-year prospective study.

    PubMed

    Hayreh, S S; Klugman, M R; Podhajsky, P; Servais, G E; Perkins, E S

    1990-01-01

    We conducted a prospective, planned study of argon laser panretinal photocoagulation (PRP) in ischemic central retinal vein occlusion (CRVO) over a 10-year period in 123 eyes. On comparing the lasered eyes versus the nonlasered eyes, there was no statistically significant difference between the two groups in the incidence of development of angle neovascularization (NV), neovascular glaucoma (NVG), retinal and/or optic disc NV, or vitreous hemorrhage, or in visual acuity. Our study, however, did show a statistically significant (P = 0.04) difference in the incidence of iris NV between the two groups, with iris NV less prevalent in the laser group than in the nonlaser group, but only when the PRP was performed within 90 days after the onset of CRVO. The other parameter which showed a statistically significant difference between the two groups was the peripheral visual fields-the laser group suffered a significantly (P less than or equal to 0.03) greater loss than the non-laser group. We discuss the implications of these findings in light of the natural history of ischemic CRVO and of ocular NV. Since the original rationale for advocating PRP in ischemic CRVO was the proven beneficial effect of PRP on ocular NV in proliferative diabetic retinopathy, we also discuss the disparities in the disease process between ischemic CRVO and proliferative diabetic retinopathy and in their responses to PRP. PMID:1698170

  18. The relationship between retinal receptor orientation and photoreceptor optics.

    PubMed

    Enoch, J M

    1978-01-01

    At this time, based on still-restricted studies, it would seem that a fundamental property of vertebrate receptor optics is anterior pointing by receptors. The anterior pointing locus is most probably a point approximating the center of the exit pupil of the eye. There is evidence for the recovery of orientation when that orientation is disturbed. One or more mechanisms mediate that orientation, and we must seek to define and understand their functional properties. We must better define how disturbance in orientation influences vision. Briefly stated, substantially disturbed receptors have reduced light-guiding capability (and hence reduced sensitivity), reduced contrast sensitivity (caused by increased cross talk and so forth), and reduced resolution capability. These combine to creat a detectable (but not necessarily common) form of amblyopia [30]. In a sense, these cases of poor acuity would seem to represent a failure of the photoreceptor alignment system. An interesting set of theories has evolved in relation to receptor alignment in the neonate. There is considerable mechanical hydraulic stress on the newborn ocular vascular system at the time of delivery. Retinal hemorrhages and transient edema of the optic papilla following intracranial pressure rise and rapid decompression later during delivery of the head commonly occur. These can readily causd disturbances in receptor alignment. In some instances the macula is involved. While hemorrhages are apparently rapidly absorbed, if foveal receptors remain misaligned during the critical period (not yet really defined) for the development of vision, central fine-resolution capability may fail to develop. That is, subsequent elaboration of the visual system is dependent upon the quality of the optically transmitted and neurally transformed retinal image during the critical period for visual development. If the capability for realignment exists and occurs after part or all of the critical period, then signs of a

  19. Shedding new light on retinal protein photochemistry.

    PubMed

    Wand, Amir; Gdor, Itay; Zhu, Jingyi; Sheves, Mordechai; Ruhman, Sanford

    2013-01-01

    The ultrafast spectroscopic investigation of novel retinal proteins challenges existing notions concerning the course of primary events in these natural photoreceptors. We review two illustrations here. The first demonstrates that changes in the initial retinal configuration can alter the duration of photochemistry by nearly an order of magnitude in Anabaena sensory rhodopsin, making it as rapid as the ballistic photoisomerization in visual pigments. This prompted a reinvestigation of the much studied bacteriorhodopsin, leading to a similar trend as well, contrary to earlier reports. The second involves the study of xanthorhodopsin, an archaeal proton pump that includes an attached light-harvesting carotenoid. Pump-probe experiments demonstrate the efficient transfer of energy from carotenoid to retinal, providing a first glimpse at a cooperative multichromophore function, which is probably characteristic of many other proteins as well. Finally, we discuss measures required to advance our knowledge from kinetics to mode-specific dynamics concerning this expanding family of biological photoreceptors.

  20. Automated retinal layer segmentation and characterization

    NASA Astrophysics Data System (ADS)

    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.

  1. [Muscular Dystrophies Involving the Retinal Function].

    PubMed

    Jägle, H

    2016-03-01

    Muscular dystrophies are rare disorders, with an incidence of approx. 20 in 100 000. Some dystrophies also affect retinal or optic nerve function. In such cases, the ophthalmological findings may be critical for differential diagnosis or patient counseling. For example in Duchenne muscular dystrophy, where the alteration in retinal function seems to reflect cerebral involvement. Other important forms are mitochondrial and metabolic disorders, such as the Kearns-Sayre syndrome and the Refsum syndrome. Molecular genetic analysis has become a major tool for differential diagnosis, but may be complex and demanding. This article gives an overview of major muscular dystrophies involving retinal function and their genetic origin, in order to guide differential diagnosis.

  2. Shedding New Light on Retinal Protein Photochemistry

    NASA Astrophysics Data System (ADS)

    Wand, Amir; Gdor, Itay; Zhu, Jingyi; Sheves, Mordechai; Ruhman, Sanford

    2013-04-01

    The ultrafast spectroscopic investigation of novel retinal proteins challenges existing notions concerning the course of primary events in these natural photoreceptors. We review two illustrations here. The first demonstrates that changes in the initial retinal configuration can alter the duration of photochemistry by nearly an order of magnitude in Anabaena sensory rhodopsin, making it as rapid as the ballistic photoisomerization in visual pigments. This prompted a reinvestigation of the much studied bacteriorhodopsin, leading to a similar trend as well, contrary to earlier reports. The second involves the study of xanthorhodopsin, an archaeal proton pump that includes an attached light-harvesting carotenoid. Pump-probe experiments demonstrate the efficient transfer of energy from carotenoid to retinal, providing a first glimpse at a cooperative multichromophore function, which is probably characteristic of many other proteins as well. Finally, we discuss measures required to advance our knowledge from kinetics to mode-specific dynamics concerning this expanding family of biological photoreceptors.

  3. Integrated computer-aided retinal photocoagulation system

    NASA Astrophysics Data System (ADS)

    Barrett, Steven F.; Wright, Cameron H. G.; Oberg, Erik D.; Rockwell, Benjamin A.; Cain, Clarence P.; Jerath, Maya R.; Rylander, Henry G., III; Welch, Ashley J.

    1996-05-01

    Successful retinal tracking subsystem testing results in vivo on rhesus monkeys using an argon continuous wave laser and an ultra-short pulse laser are presented. Progress on developing an integrated robotic retinal laser surgery system is also presented. Several interesting areas of study have developed: (1) 'doughnut' shaped lesions that occur under certain combinations of laser power, spot size, and irradiation time complicating measurements of central lesion reflectance, (2) the optimal retinal field of view to achieve simultaneous tracking and lesion parameter control, and (3) a fully digital versus a hybrid analog/digital tracker using confocal reflectometry integrated system implementation. These areas are investigated in detail in this paper. The hybrid system warrants a separate presentation and appears in another paper at this conference.

  4. Molecular biology of retinal ganglion cells.

    PubMed Central

    Xiang, M; Zhou, H; Nathans, J

    1996-01-01

    Retinal ganglion cells are the output neurons that encode and transmit information from the eye to the brain. Their diverse physiologic and anatomic properties have been intensively studied and appear to account well for a number of psychophysical phenomena such as lateral inhibition and chromatic opponency. In this paper, we summarize our current view of retinal ganglion cell properties and pose a number of questions regarding underlying molecular mechanisms. As an example of one approach to understanding molecular mechanisms, we describe recent work on several POU domain transcription factors that are expressed in subsets of retinal ganglion cells and that appear to be involved in ganglion cell development. Images Fig. 1 Fig. 2 Fig. 4 Fig. 5 Fig. 6 PMID:8570601

  5. [Severe hereditary retinal diseases in childhood].

    PubMed

    Lorenz, B

    1996-01-01

    In dependence on the various statistics, hereditary causes are identified in up to 50% of the visually handicapped and blind school children. Most common are retinal disorders, which account for 15 to 55%. The most important diseases are briefly reviewed: Leber's congenital amaurosis, rod monochromacy, blue cone monochromacy, congenital stationary night blindness (CSNB), X-linked retinitis pigmentosa, Usher syndromes, Bardet-Biedl syndrome, juvenile neuronal ceroid lipofuscinosis Spielmeyer-Vogt, the various forms of albinism, exsudative vitreoretinopathies including Norrie's disease, as well as Stargardt's macular dystrophy, vitelliform macular dystrophy, and hereditary retinoblastoma. In addition to the clinical symptoms, general genetic principles are stressed, such as mode of inheritance, heterogeneity, expressivity, penetrance, age at manifestation, X-chromosomal gene inactivation, and variability. They all have to be taken into account to correctly establish the diagnosis, to identify family members at risk, and to provide adequate genetic counselling. An overview of the actual molecular genetics of the various retinal disorders is also given.

  6. Retinal Fiber Tracing by In Ovo Electroporation

    NASA Astrophysics Data System (ADS)

    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.

  7. Autophagy in light-induced retinal damage.

    PubMed

    Chen, Yu; Perusek, Lindsay; Maeda, Akiko

    2016-03-01

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

  8. Retinoschisis transposition following a retinal detachment repair

    PubMed Central

    McVeigh, Katherine; Keller, Johannes; Haynes, Richard J.

    2015-01-01

    Objective: The authors have observed this phenomenon of translocation of the schisis cavity in a few previous cases and aim to report this unusual finding. Method: A patient with known superotemporal retinoschisis developed a distinctly separate inferotemporal retinal detachment in his left eye. This was repaired with a vitrectomy, cryotherapy and C2F6 tamponade under local anaesthetic. Following surgery, the retinoschisis was found in the inferonasal quadrant of the eye and remained stable as the gas dispersed. Result: We hypothesise that the tamponading agent compressed the viscous fluid within the area of schisis, displacing the area of schisis circumferentially. Conclusion: This case emphasises that as long as the retinal breaks are properly sealed, no intervention is required with the schisis during rhegmatogenous retinal detachment surgery.

  9. Minimally invasive curved-micro-drainer (CMD) capable of innocuous drainage of subretinal fluid for the treatment of retinal detachment.

    PubMed

    Ma, Yonghao; Lee, ChangYeol; Li, Cheng Guo; You, Yong Sung; Sung, Ho Lee; Jung, Hyungil

    2016-08-01

    Retinal detachment is a serious vision threatening disease. Current consensus for the treatment of retinal detachment is to reattach the retina onto the choroid layer by drainage of accumulated subretinal fluid. Although several surgical methods have been developed, no satisfactory visual outcome has been obtained without surgical complications such as unintended puncture and hemorrhage of the retina and choroid tissue. In this study, we developed a novel Curved-Micro-Drainer (CMD) for the innocuous drainage of subretinal fluid. It is a curved structure with a 15° beveled tip that is 5 mm in length, with an 80 μm inner diameter and a 100 μm outer diameter. This high inner-to-outer diameter ratio of CMD with a 100 μm outer diameter allows efficient drainage of highly viscous subretinal fluid in a minimally invasive manner. In addition, the curved structure precisely matches the spherical ocular structure, which facilitates the CMD insertion into the subretinal space without choroid tissue damage. We demonstrate that the optimized CMD allows for the innocuous drainage of the viscous subretinal fluid from the porcine eye, whereas the traditional hypodermic needle (31-gauge) induces severe retinal and choroid damage. CMD can overcome a critical safety issue and is a potential alternative to conventional surgical interventions for the innocuous drainage of subretinal fluid. PMID:27412289

  10. Baseline characteristics and risk factors of retinal vein occlusion: a study by the Korean RVO Study Group.

    PubMed

    Lee, Joo Yong; Yoon, Young Hee; Kim, Ha Kyoung; Yoon, Hee Seong; Kang, Se Woong; Kim, June-Gone; Park, Kyu Hyung; Jo, Young Joon

    2013-01-01

    We investigated the demographic characteristics and risk factors of Korean patients with naÏve central or branch retinal vein occlusion (CRVO or BRVO). This study enrolled 41 clinical sites throughout Korea and included 557 consecutive patients with retinal vein occlusion (RVO) from May through November 2010. A total of 557 patients with new-onset RVO participated in this study. Two hundred and three (36.4%) patients were diagnosed with CRVO and 354 (63.6%) patients were diagnosed with BRVO. Comparisons between the two groups showed that the prevalence of diabetes mellitus was significantly higher in CRVO patients and hypertension was significantly higher in BRVO patients (P = 0.001 and 0.002, respectively). Poor baseline visual acuity was significantly associated with female and old age in BRVO patients (P = 0.002 and 0.013, respectively), whereas the wide intraretinal hemorrhage (CRVO, P = 0.029; BRVO, P < 0.001) and the macular ischemia (CRVO, P < 0.001; BRVO, P < 0.001) were associated with both groups. The study results show the clinical features of RVO in Korean patients. Hypertension is strongly associated with BRVO and diabetes mellitus is more strongly associated with CRVO in Korean patients with RVO. As the first nationwide study performed by the Korean Retinal Society, the results of this study can be applied to future studies on RVO.

  11. Transplantation of Embryonic and Induced Pluripotent Stem Cell-Derived 3D Retinal Sheets into Retinal Degenerative Mice

    PubMed Central

    Assawachananont, Juthaporn; Mandai, Michiko; Okamoto, Satoshi; Yamada, Chikako; Eiraku, Mototsugu; Yonemura, Shigenobu; Sasai, Yoshiki; Takahashi, Masayo

    2014-01-01

    Summary In this article, we show that mouse embryonic stem cell- or induced pluripotent stem cell-derived 3D retinal tissue developed a structured outer nuclear layer (ONL) with complete inner and outer segments even in an advanced retinal degeneration model (rd1) that lacked ONL. We also observed host-graft synaptic connections by immunohistochemistry. This study provides a “proof of concept” for retinal sheet transplantation therapy for advanced retinal degenerative diseases. PMID:24936453

  12. Reading visual braille with a retinal prosthesis.

    PubMed

    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.

  13. Protease nexin-1 regulates retinal vascular development.

    PubMed

    Selbonne, Sonia; Francois, Deborah; Raoul, William; Boulaftali, Yacine; Sennlaub, Florian; Jandrot-Perrus, Martine; Bouton, Marie-Christine; Arocas, Véronique

    2015-10-01

    We recently identified protease nexin-1 (PN-1) or serpinE2, as a possibly underestimated player in maintaining angiogenic balance. Here, we used the well-characterized postnatal vascular development of newborn mouse retina to further investigate the role and the mechanism of action of PN-1 in physiological angiogenesis. The development of retinal vasculature was analysed by endothelial cell staining with isolectin B4. PN-1-deficient (PN-1(-/-)) retina displayed increased vascularization in the postnatal period, with elevated capillary thickness and density, compared to their wild-type littermate (WT). Moreover, PN-1(-/-) retina presented more veins/arteries than WT retina. The kinetics of retinal vasculature development, retinal VEGF expression and overall retinal structure were similar in WT and PN-1(-/-) mice, but we observed a hyperproliferation of vascular cells in PN-1(-/-) retina. Expression of PN-1 was analysed by immunoblotting and X-Gal staining of retinas from mice expressing beta-galactosidase under a PN-1 promoter. PN-1 was highly expressed in the first week following birth and then progressively decreased to a low level in adult retina where it localized on the retinal arteries. PCR arrays performed on mouse retinal RNA identified two angiogenesis-related factors, midkine and Smad5, that were overexpressed in PN-1(-/-) newborn mice and this was confirmed by RT-PCR. Both the higher vascularization and the overexpression of midkine and Smad5 mRNA were also observed in gastrocnemius muscle of PN-1(-/-) mice, suggesting that PN-1 interferes with these pathways. Together, our results demonstrate that PN-1 strongly limits physiological angiogenesis and suggest that modulation of PN-1 expression could represent a new way to regulate angiogenesis.

  14. Retinal Oximetry in a Healthy Japanese Population

    PubMed Central

    Nakano, Yuki; Shimazaki, Takeru; Kobayashi, Nobuko; Miyoshi, Yukiko; Ono, Aoi; Kobayashi, Mamoru; Shiragami, Chieko; Hirooka, Kazuyuki; Tsujikawa, Akitaka

    2016-01-01

    Purpose To establish the normative database of retinal oximetry using Oxymap T1 in a healthy Japanese population, and study the reproducibility of the measurements in Japanese. Methods We measured oxygen saturation in the major retinal vessels with Oxymap T1 in 252 eyes of 252 healthy Japanese subjects. Fundus images acquired using Oxymap T1 were processed using built-in Oxymap Analyzer software. Reproducibility of retinal oximetry was investigated using 20 eyes of 20 healthy subjects. Results The mean retinal oxygen saturation of 4 quadrants in healthy Japanese was 97.0 ± 6.9% in arteries and 52.8 ± 8.3% in veins. The mean arteriovenous difference in oxygen saturation was 44.2 ± 9.2%. Both arterial and venous oxygen saturation were significantly lower in the temporal side of the retina, especially in the temporal-inferior vessels. However, the arteriovenous difference in oxygen saturation was limited in the 4 quadrants. Interphotograph, intervisit, and interevaluator intraclass correlation coefficients were 0.936–0.979, 0.809–0.837, and 0.732–0.947, respectively. In the major retinal arteries, oxygen saturation increased with age (r = 0.18, p<0.01), at a rate of 0.67% per 10 years. However, venous oxygen saturation showed no correlation with age. Conclusions This study provides the normative database for the Japanese population. The arterial saturation value appears to be higher than other previous studies. Mean retinal oximetry in 4 quadrants with Oxymap T1 has high reproducibility. PMID:27434373

  15. Does Glaucoma Share Common Pathogenesis with Branch Retinal Vein Occlusion?

    PubMed Central

    Han, Jong Chul; Eo, Doo Ri; Lee, Taek Kwan; Shin, Jong Hoon; Kee, Changwon

    2016-01-01

    Background To evaluate the observed prevalence and the optic nerve head (ONH) characteristics of normal tension glaucoma (NTG)-suspect eyes in branch retinal vein occulusion (BRVO) eyes in Korean population. Methods This was a retrospective observational study. We investigated 445 BRVO eyes that were diagnosed in the retina clinic of Samsung Medical Center between March 2005 and December 2011. The observed prevalence of NTG-suspect in BRVO eyes was evaluated compared to the previous population based study. In addition, NTG-suspect cases in BRVO were divided into three groups based on the characteristics of optic disc morphology. Results In 445 BRVO eyes, 30 eyes were excluded from the present study. In 415 BRVO eyes, 4.3% (18 eyes) (95% confident interval [CI], 2.4–6.3%) were diagnosed with suspect glaucoma and this is not significantly different from the result in the general Korean population (P = 0.09). We classified the NTG-suspect eyes into three groups such as disc rim notching and thinning type (Group 1; 55.6%), optic cup-sited hemorrhage type (Group 2; 16.7%) and disc rim thinning and pallor type (Group 3; 27.8%). NTG-suspect in the fellow eye were only found in group 1 (80%) and group 2 (67%), but not in group 3 (P = 0.01). Conclusions BRVO and glaucoma seem to have no common vascular pathogenesis in consideration of the prevalence of NTG-suspect in BRVO eyes compared to general Korean population. PMID:27304065

  16. [Retinal vein occlusion: an interdisciplinary approach].

    PubMed

    Hatz, Katja; Martinez, Maria

    2016-01-01

    Retinal vein occlusion provide a common cause of significant visual reduction but also late ocular complications. The medical care of these patients pursue two goals: On the one hand vision threatening complications need to be identified and treated, and on the other hand treatable risk factors are need to be identified and treated. This paper summarizes the common ophthalmological therapeutic approaches as well as recommended medical evaluations carried out by the general practitioner. This supports the interdisciplinary approach in evaluating and treating retinal vein occlusions by ophthalmologists and the general practitioners/specialist in internal medicine. PMID:26982647

  17. Retinal manifestations of ophthalmic artery hypoperfusion.

    PubMed

    Ong, Terrence J; Paine, Mark; O'Day, Justin

    2002-08-01

    Ophthalmic artery hypoperfusion is a relatively uncommon clinical entity. This study illustrates the posterior segment findings of ophthalmic artery hypoperfusion in a series of nine patients. Colour photographs and relevant fluorescein angiograms highlighting the findings are shown. The retinal manifestations of ophthalmic artery hypoperfusion in this series of patients include midperipheral haemorrhages, dilated retinal veins, optic disk collaterals, optic disk neo-vascularization, cotton wool spots, grey intraretinal lesions, fundus pallor, optic disk swelling and choroidal infarcts. Recognition of the ophthalmic changes in this condition may lead to detection of carotid artery disease, the surgical and medical treatment of which has important bearing on patient management.

  18. Proliferative diabetic retinopathy in typical retinitis pigmentosa.

    PubMed

    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

  19. Review: R28 retinal precursor cells: The first 20 years

    PubMed Central

    2014-01-01

    The R28 retinal precursor cell line was established 20 years ago, originating from a postnatal day 6 rat retinal culture immortalized with the 12S E1A (NP-040507) gene of the adenovirus in a replication-incompetent viral vector. Since that time, R28 cells have been characterized and used for a variety of in vitro and in vivo studies of retinal cell behavior, including differentiation, neuroprotection, cytotoxicity, and light stimulation, as well as retinal gene expression and neuronal function. While no cell culture is equivalent to the intact eye, R28 cells continue to provide an important experimental system for the study of many retinal processes. PMID:24644404

  20. Myxoma of the kidney associated with hemorrhage.

    PubMed

    Shah, Abhishek; Sun, Wenbin; Cao, Dianbo

    2013-06-01

    Myxomas are relatively rare tumors and most of them occur in the heart, skin, and soft tissues and bones. Renal myxomas are extremely rare neoplasms and very few cases have been reported in the literature. A review of medical literatures reveals no previous description of renal myxoma complicated with extensive areas of hemorrhage. So, we report such a case in a 43-year-old female. She had a left renal mass incidentally discovered during ultrasonography at a regular health checkup, and further computed tomography scan showed 4.9 × 3.1 cm mass with circular septal enhancement and ill-defined margin with the left psoas major muscle. Radical nephrectomy was performed because of suspected malignant renal tumor. Postoperative histopathology of resected specimen revealed the typical appearance of a myxoma associated with extensive hemorrhage. PMID:24426654

  1. Intracranial hemorrhage associated with methanol intoxication.

    PubMed

    Sebe, Ahmet; Satar, Salim; Uzun, Belkan; Topal, Metin; Yesilagac, Hasan; Avci, Andakkan

    2006-12-01

    Methanol is a common component of gasoline, antifreeze, washer fluid, perfume, household cleaners and various other industrial products. Acute methanol poisoning produces severe metabolic acidosis, serious neurologic sequelae and rarely imaging findings. In this paper, we describe a 35-year-old man with methanol intoxication who was in a comatose stage. Computed tomography (CT) showed widespread brain edema and hemorrhages localized in the supratentorial region of the temporal lobe, nearly 3 x 1 cm in a crescent shape, in the white matter surrounding the capsula externa and extending to the periventricular white matter and occipital lobes. Temporal lobe hemorrhage in our patient might also have been due to the effect of heparinization during hemodialysis, metabolic and lactic acidosis, or formate.

  2. Infection Control During Filoviral Hemorrhagic Fever Outbreaks

    PubMed Central

    Vanessa, N Raabe; Matthias, Borchert

    2012-01-01

    Breaking the human-to-human transmission cycle remains the cornerstone of infection control during filoviral (Ebola and Marburg) hemorrhagic fever outbreaks. This requires effective identification and isolation of cases, timely contact tracing and monitoring, proper usage of barrier personal protection gear by health workers, and safely conducted burials. Solely implementing these measures is insufficient for infection control; control efforts must be culturally sensitive and conducted in a transparent manner to promote the necessary trust between the community and infection control team in order to succeed. This article provides a review of the literature on infection control during filoviral hemorrhagic fever outbreaks focusing on outbreaks in a developing setting and lessons learned from previous outbreaks. The primary search database used to review the literature was PUBMED, the National Library of Medicine website. PMID:22529631

  3. Intracerebral Hemorrhage, Oxidative Stress, and Antioxidant Therapy

    PubMed Central

    Duan, Xiaochun; Wen, Zunjia; Shen, Haitao; Shen, Meifen

    2016-01-01

    Hemorrhagic stroke is a common and severe neurological disorder and is associated with high rates of mortality and morbidity, especially for intracerebral hemorrhage (ICH). Increasing evidence demonstrates that oxidative stress responses participate in the pathophysiological processes of secondary brain injury (SBI) following ICH. The mechanisms involved in interoperable systems include endoplasmic reticulum (ER) stress, neuronal apoptosis and necrosis, inflammation, and autophagy. In this review, we summarized some promising advances in the field of oxidative stress and ICH, including contained animal and human investigations. We also discussed the role of oxidative stress, systemic oxidative stress responses, and some research of potential therapeutic options aimed at reducing oxidative stress to protect the neuronal function after ICH, focusing on the challenges of translation between preclinical and clinical studies, and potential post-ICH antioxidative therapeutic approaches. PMID:27190572

  4. Viruses Causing Hemorrhagic Fever. Safety Laboratory Procedures

    PubMed Central

    Cobo, Fernando

    2016-01-01

    Viral hemorrhagic fevers are diseases caused by viruses which belong to different families, many of them causing severe diseases. These viruses may produce different symptomatology together with a severe multisystem syndrome, and the final result might be the production of hemorrhages in several sites of the body. The majority of them have no other treatment than supportive therapy, although some antiviral drugs can be used in some circumstances. Transmission of VHF has been demonstrated through contact with animal vectors or person-to-person through the contact with body fluids. No risk of transmission has been found during the incubation period, but when the viral load is high the risk of transmission is greatest. Both health care and clinical laboratory workers must safely handle patients and specimens by taking all required precautions during their management. PMID:27014378

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

    NASA Astrophysics Data System (ADS)

    Wand, A.; Rozin, R.; Eliash, T.; Friedman, N.; Jung, K. H.; Sheves, M.; Ruhman, S.

    2013-03-01

    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.

  6. Management of inferior retinal breaks during pars plana vitrectomy for retinal detachment

    PubMed Central

    Tanner, V; Minihan, M; Williamson, T

    2001-01-01

    AIMS—To determine whether it is necessary to support inferior retinal breaks with a scleral explant during pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RD).
METHODS—A prospective study was carried out on nine eyes of nine consecutive patients undergoing PPV for primary RD with associated inferior retinal breaks and no significant proliferative vitreoretinopathy.
RESULTS—Eight eyes were successfully reattached with a single operation. No cases presented with redetachment because of failed closure of the original inferior breaks.
CONCLUSIONS—It is not necessary to support inferior retinal breaks with a scleral explant during PPV for primary RD repair in selected cases.

 PMID:11264142

  7. Hemorrhagic Encephalopathy From Acute Baking Soda Ingestion.

    PubMed

    Hughes, Adrienne; Brown, Alisha; Valento, Matthew

    2016-09-01

    Baking soda is a readily available household product composed of sodium bicarbonate. It can be used as a home remedy to treat dyspepsia. If used in excessive amounts, baking soda has the potential to cause a variety of serious metabolic abnormalities. We believe this is the first reported case of hemorrhagic encephalopathy induced by baking soda ingestion. Healthcare providers should be aware of the dangers of baking soda misuse and the associated adverse effects. PMID:27625729

  8. Hemorrhagic Encephalopathy From Acute Baking Soda Ingestion

    PubMed Central

    Hughes, Adrienne; Brown, Alisha; Valento, Matthew

    2016-01-01

    Baking soda is a readily available household product composed of sodium bicarbonate. It can be used as a home remedy to treat dyspepsia. If used in excessive amounts, baking soda has the potential to cause a variety of serious metabolic abnormalities. We believe this is the first reported case of hemorrhagic encephalopathy induced by baking soda ingestion. Healthcare providers should be aware of the dangers of baking soda misuse and the associated adverse effects. PMID:27625729

  9. Advances in fluid resuscitation of hemorrhagic shock

    PubMed Central

    Tremblay, Lorraine N.; Rizoli, Sandro B.; Brenneman, Frederick D.

    2001-01-01

    The optimal fluid for resuscitation in hemorrhagic shock would combine the volume expansion and oxygen-carrying capacity of blood without the need for cross-matching or the risk of disease transmission. Although the ideal fluid has yet to be discovered, current options are discussed in this review, including crystalloids, colloids, blood and blood substitutes. The future role of blood substitutes is not yet defined, but the potential advantages in trauma or elective surgery may prove to be enormous. PMID:11407826

  10. [Cerebral hemorrhage associated with the use phenylpropanolamine].

    PubMed

    Barinagarrementería, F; Méndez, A; Vega, F

    1990-10-01

    Phenylpropanolamine is a sympatheticomimetic agent which is widely used in pharmacologic preparations to treat nasal congestion, and to produce and anorexigenic or stimulant action. In the last years complications affecting the nervous system or the general condition have been reported. There is still controversy with regard to the safety of this pharmacologic agent. In this study we report two cases of parenchymal cerebral hemorrhage secondary to phenylpropanolamine administration. In the second case we observed angiographic findings of a reversible vasculopathy.

  11. Delayed postoperative hemorrhage complicating chalazion surgery.

    PubMed Central

    Procope, J. A.; Kidwell, E. D.

    1994-01-01

    Chalazion surgery is a common minor ophthalmic surgical procedure used to treat chalazia after conservative measures have failed. Complications are infrequent and generally easily managed with minimal morbidity. This article presents an atypical case of an elderly woman with a history of hypertension who experienced sudden profuse hemorrhaging 10 days after chalazion surgery. The clinical findings are presented along with a brief overview of the relevant vascular anatomy of the eyelid and a discussion of possible etiologic factors. PMID:7807576

  12. Hemorrhagic Encephalopathy From Acute Baking Soda Ingestion.

    PubMed

    Hughes, Adrienne; Brown, Alisha; Valento, Matthew

    2016-09-01

    Baking soda is a readily available household product composed of sodium bicarbonate. It can be used as a home remedy to treat dyspepsia. If used in excessive amounts, baking soda has the potential to cause a variety of serious metabolic abnormalities. We believe this is the first reported case of hemorrhagic encephalopathy induced by baking soda ingestion. Healthcare providers should be aware of the dangers of baking soda misuse and the associated adverse effects.

  13. Hemorrhagic Encephalopathy From Acute Baking Soda Ingestion

    PubMed Central

    Hughes, Adrienne; Brown, Alisha; Valento, Matthew

    2016-01-01

    Baking soda is a readily available household product composed of sodium bicarbonate. It can be used as a home remedy to treat dyspepsia. If used in excessive amounts, baking soda has the potential to cause a variety of serious metabolic abnormalities. We believe this is the first reported case of hemorrhagic encephalopathy induced by baking soda ingestion. Healthcare providers should be aware of the dangers of baking soda misuse and the associated adverse effects.

  14. Spinal angiolipoma with acute subarachnoid hemorrhage.

    PubMed

    Raghavendra, S; Krishnamoorthy, T; Ashalatha, R; Kesavadas, C

    2007-10-01

    Angiolipoma is a rare tumor of the spine commonly presenting with compressive myelopathy. We report a spinal angiolipoma in a 14-year-old patient with acute spinal subarachnoid hemorrhage (SAH). To our knowledge this is the first reported case of a spinal angiolipoma presenting with SAH, associated with post-subclavian coarctation with diffuse hypoplasia of the descending aorta. This association of coarctation of aorta, aortic hypoplasia and spinal angiolipoma has also not been reported previously.

  15. Microscopic Inner Retinal Hyper-Reflective Phenotypes in Retinal and Neurologic Disease

    PubMed Central

    Scoles, Drew; Higgins, Brian P.; Cooper, Robert F.; Dubis, Adam M.; Summerfelt, Phyllis; Weinberg, David V.; Kim, Judy E.; Stepien, Kimberly E.; Carroll, Joseph; Dubra, Alfredo

    2014-01-01

    Purpose. We surveyed inner retinal microscopic features in retinal and neurologic disease using a reflectance confocal adaptive optics scanning light ophthalmoscope (AOSLO). Methods. Inner retinal images from 101 subjects affected by one of 38 retinal or neurologic conditions and 11 subjects with no known eye disease were examined for the presence of hyper-reflective features other than vasculature, retinal nerve fiber layer, and foveal pit reflex. The hyper-reflective features in the AOSLO images were grouped based on size, location, and subjective texture. Clinical imaging, including optical coherence tomography (OCT), scanning laser ophthalmoscopy, and fundus photography was analyzed for comparison. Results. Seven categories of hyper-reflective inner retinal structures were identified, namely punctate reflectivity, nummular (disc-shaped) reflectivity, granular membrane, waxy membrane, vessel-associated membrane, microcysts, and striate reflectivity. Punctate and nummular reflectivity also was found commonly in normal volunteers, but the features in the remaining five categories were found only in subjects with retinal or neurologic disease. Some of the features were found to change substantially between follow up imaging months apart. Conclusions. Confocal reflectance AOSLO imaging revealed a diverse spectrum of normal and pathologic hyper-reflective inner and epiretinal features, some of which were previously unreported. Notably, these features were not disease-specific, suggesting that they might correspond to common mechanisms of degeneration or repair in pathologic states. Although prospective studies with larger and better characterized populations, along with imaging of more extensive retinal areas are needed, the hyper-reflective structures reported here could be used as disease biomarkers, provided their specificity is studied further. PMID:24894394

  16. Inner retinal preservation in rat models of retinal degeneration implanted with subretinal photovoltaic arrays.

    PubMed

    Light, Jacob G; Fransen, James W; Adekunle, Adewumi N; Adkins, Alice; Pangeni, Gobinda; Loudin, James; Mathieson, Keith; Palanker, Daniel V; McCall, Maureen A; Pardue, Machelle T

    2014-11-01

    Photovoltaic arrays (PVA) implanted into the subretinal space of patients with retinitis pigmentosa (RP) are designed to electrically stimulate the remaining inner retinal circuitry in response to incident light, thereby recreating a visual signal when photoreceptor function declines or is lost. Preservation of inner retinal circuitry is critical to the fidelity of this transmitted signal to ganglion cells and beyond to higher visual targets. Post-implantation loss of retinal interneurons or excessive glial scarring could diminish and/or eliminate PVA-evoked signal transmission. As such, assessing the morphology of the inner retina in RP animal models with subretinal PVAs is an important step in defining biocompatibility and predicting success of signal transmission. In this study, we used immunohistochemical methods to qualitatively and quantitatively compare inner retinal morphology after the implantation of a PVA in two RP models: the Royal College of Surgeons (RCS) or transgenic S334ter-line 3 (S334ter-3) rhodopsin mutant rat. Two PVA designs were compared. In the RCS rat, we implanted devices in the subretinal space at 4 weeks of age and histologically examined them at 8 weeks of age and found inner retinal morphology preservation with both PVA devices. In the S334ter-3 rat, we implanted devices at 6-12 weeks of age and again, inner retinal morphology was generally preserved with either PVA design 16-26 weeks post-implantation. Specifically, the length of rod bipolar cells and numbers of cholinergic amacrine cells were maintained along with their characteristic inner plexiform lamination patterns. Throughout the implanted retinas we found nonspecific glial reaction, but none showed additional glial scarring at the implant site. Our results indicate that subretinally implanted PVAs are well-tolerated in rodent RP models and that the inner retinal circuitry is preserved, consistent with our published results showing implant-evoked signal transmission. PMID

  17. Retinal Changes in an ATP-Induced Model of Retinal Degeneration

    PubMed Central

    Aplin, Felix P.; Vessey, Kirstan A.; Luu, Chi D.; Guymer, Robyn H.; Shepherd, Robert K.; Fletcher, Erica L.

    2016-01-01

    In rodents and felines, intravitreal administration of adenosine triphosphate (ATP) has been shown to induce photoreceptor death providing a tractable model of retinal degeneration in these species. This study investigated the long term effects of photoreceptor loss in an ATP induced feline model of retinal degeneration. Six normal sighted felines were unilaterally blinded using intravitreal ATP injections and assessed using electroretinography (ERG) and optical coherence tomography (OCT). At 30 h (n = 3) or 12 weeks (n = 3) post-injection, the animals were euthanized and the eyes enucleated. Retinae were sectioned and labeled using immunohistochemistry for markers of cell death, neural remodeling and gliosis. Ongoing cell death and retinal degeneration was observed in the outer retina at both 30 h and 12 weeks following unilateral ATP injection. Markers of mid to late-stage retinal remodeling such as cell displacement and aberrant neurite growth were observed in the inner retina at 12 weeks post-injection. Ganglion cells appeared to remain intact in ATP injected eyes. Müller cell gliosis was observed throughout the inner and outer retina, in some parts completely enveloping and/or displacing the surviving neural tissue. Our data suggests that the ATP injected feline retina continues to undergo progressive retinal degeneration and exhibits abnormalities consistent with a description of retinal remodeling commonly seen in other models of retinal degeneration. These findings validate the use of intravitreal ATP injection in feline as a large animal model of retinal degeneration which may aid in development of therapies aiming to restore visual function after photoreceptor degeneration. PMID:27199678

  18. Inner retinal preservation in rat models of retinal degeneration implanted with subretinal photovoltaic arrays

    PubMed Central

    Light, Jacob G.; Fransen, James W.; Adekunle, Adewumi N.; Adkins, Alice; Pangeni, Gobinda; Loudin, James; Mathieson, Keith; Palanker, Daniel V.; McCall, Maureen A.; Pardue, Machelle T.

    2015-01-01

    Photovoltaic arrays (PVA) implanted into the subretinal space of patients with retinitis pigmentosa (RP) are designed to electrically stimulate the remaining inner retinal circuitry in response to incident light, thereby recreating a visual signal when photoreceptor function declines or is lost. Preservation of inner retinal circuitry is critical to the fidelity of this transmitted signal to ganglion cells and beyond to higher visual targets. Post-implantation loss of retinal interneurons or excessive glial scarring could diminish and/or eliminate PVA-evoked signal transmission. As such, assessing the morphology of the inner retina in RP animal models with subretinal PVAs is an important step in defining biocompatibility and predicting success of signal transmission. In this study, we used immunohistochemical methods to qualitatively and quantitatively compare inner retinal morphology after the implantation of a PVA in two RP models: the Royal College of Surgeons (RCS) or transgenic S334ter-line 3 (S334ter-3) rhodopsin mutant rat. Two PVA designs were compared. In the RCS rat, we implanted devices in the subretinal space at 4 weeks of age and histologically examined them at 8 weeks of age and found inner retinal morphology preservation with both PVA devices. In the S334ter-3 rat, we implanted devices at 6 to 12 weeks of age and again, inner retinal morphology was generally preserved with either PVA design 16 to 26 weeks post implantation. Specifically, the length of rod bipolar cells and numbers of cholinergic amacrine cells were maintained along with their characteristic inner plexiform lamination patterns. Throughout the implanted retinas we found nonspecific glial reaction, but none showed additional glial scarring at the implant site. Our results indicate that subretinally implanted PVAs are well-tolerated in rodent RP models and that the inner retinal circuitry is preserved, consistent with our published results showing implant-evoked signal transmission. PMID

  19. Two cases of asymptomatic massive fetomaternal hemorrhage.

    PubMed

    Peedin, Alexis R; Mazepa, Marshall A; Park, Yara A; Weimer, Eric T; Schmitz, John L; Raval, Jay S

    2015-04-01

    Evaluation of fetomaternal hemorrhage (FMH) in the immediate postpartum period is critical for the timely administration of Rh immunoglobulin (RhIG) prophylaxis to minimize the risk of alloimmunization in D-negative mothers of D-positive newborns. We report a series of two clinically-unsuspected cases of massive FMHs identified at our university medical center. Retrospective records of two cases of massive FMH were investigated using the electronic medical record. After positive fetal bleed screens, flow cytometric analysis for hemoglobin F was performed to quantify the volume of the hemorrhages in both cases. Flow cytometric enumeration with anti-D was also performed in one case. The two patients had 209.5 and 75 mL of fetal blood in circulation, resulting in 8 and 4 doses of RhIG administered, respectively. For the former patient, flow cytometric analysis with anti-D ruled out hereditary persistence of fetal hemoglobin and supported the fetal origin of the red cells. Due to the clinically-silent nature of both hemorrhages, further evaluation of the newborns' blood was not performed. These cases highlight the importance of rapidly obtaining accurate measurements of fetal blood loss via flow cytometric analysis in cases of FMH, particularly in clinically-unsuspected cases, to ensure timely administration of adequate immunoprophylaxis to D-negative mothers. PMID:25736586

  20. Characteristics of uncontrolled hemorrhage in cardiac surgery.

    PubMed

    Trowbridge, Cody; Stammers, Alfred; Klayman, Myra; Brindisi, Nicholas; Woods, Edward

    2008-06-01

    Patients with uncontrolled hemorrhage require massive transfusion therapy and consume a large fraction of blood bank resources. Institutional guidelines have been established for treatment, but early identification and prevention in susceptible patients remains challenging. Uncontrolled hemorrhage was defined as meeting institutional guidelines for recombinant FVIIa administration. Patients who received rFVIIa were compared with patients who did not require the therapy but who were operated on during the same time period. After institutional review board approval, demographic, operative, and transfusion data were analyzed from a prospective database. Patients receiving rFVIIa were more likely to undergo multiple procedures (2.6 +/- 0.8 vs. 1.8 +/- 0.8; p < .001); aortic surgery (59% vs. 11%; p < .005); have a higher Cleveland Clinic Clinical Severity score (7.8 +/- 2.7 vs. 5.5 +/- 4.0; p < .005); require longer bypass (265 +/- 92 min vs. 159 +/- 63 min; p < .001), cross-clamp (182 +/- 68 min vs. 112 +/- 56 min; p < .001), and circulatory arrest (15 +/- 24 min vs. 2 +/- 7 min; p < .05) times; and require more autotransfusion (2580 +/- 1847 mL vs. 690 +/- 380 mL; p < .05). Uncontrolled hemorrhage is associated with more complex surgery requiring longer bypass times and more autotransfusion.

  1. Hemorrhage control by microsecond electrical pulses

    NASA Astrophysics Data System (ADS)

    Mandel, Yossi; Manivanh, Richard; Dalal, Roopa; Huie, Phil; Wang, Jenny; Brinton, Mark; Palanker, Daniel

    2013-02-01

    Non-compressible hemorrhages are the most common preventable cause of death on battlefield or in civilian traumatic injuries. We report the use of sub-millisecond pulses of electric current to induce rapid constriction in femoral and mesenteric arteries and veins in rats. Extent of vascular constriction could be modulated by pulse duration, amplitude and repetition rate. Electrically-induced vasoconstriction could be maintained at steady level until the end of stimulation, and blood vessels dilated back to their original size within a few minutes after the end of stimulation. At higher settings, a blood clotting could be introduced, leading to complete and permanent occlusion of the vessels. The latter regime dramatically decreased the bleeding rate in the injured femoral and mesenteric arteries, with a complete hemorrhage arrest achieved within seconds. The average blood loss from the treated femoral artery was about 7 times less than that of a non-treated control. This new treatment modality offers a promising approach to non-damaging control of bleeding during surgery, and to efficient hemorrhage arrest in trauma patients.

  2. Fluorosilicone oil in the treatment of retinal detachment.

    PubMed Central

    Gremillion, C M; Peyman, G A; Liu, K R; Naguib, K S

    1990-01-01

    We evaluated the use of a heavier-than-water fluorinated silicone oil in the treatment of 30 selected cases of complicated retinal detachment from January 1988 to July 1989. Proliferative vitreoretinopathy grade C-2 or greater accounted for 19 cases, proliferative diabetic retinopathy with traction detachment for two cases, giant retinal tears five, ruptured globe with retinal detachment two, massive choroidal effusion with retinal detachment one, and acute retinal necrosis with retinal detachment one. Initial retinal reattachment was achieved in all cases. Complications included redetachment seven (23%), cataract six (75% of phakic patients), raised intraocular pressure four (13%), hypotony four (13%), keratopathy three (10%), uveitis-synechia formation three (10%), phthisis two (3%), choroidal haemorrhage one (3%), and vitreous haemorrhage one (3%). Postoperative visual acuities with at least six months' follow-up range from no light perception to 20/50, with seven patients (23%) 20/400 or better. Images PMID:2223698

  3. Fluorosilicone oil in the treatment of retinal detachment.

    PubMed

    Gremillion, C M; Peyman, G A; Liu, K R; Naguib, K S

    1990-11-01

    We evaluated the use of a heavier-than-water fluorinated silicone oil in the treatment of 30 selected cases of complicated retinal detachment from January 1988 to July 1989. Proliferative vitreoretinopathy grade C-2 or greater accounted for 19 cases, proliferative diabetic retinopathy with traction detachment for two cases, giant retinal tears five, ruptured globe with retinal detachment two, massive choroidal effusion with retinal detachment one, and acute retinal necrosis with retinal detachment one. Initial retinal reattachment was achieved in all cases. Complications included redetachment seven (23%), cataract six (75% of phakic patients), raised intraocular pressure four (13%), hypotony four (13%), keratopathy three (10%), uveitis-synechia formation three (10%), phthisis two (3%), choroidal haemorrhage one (3%), and vitreous haemorrhage one (3%). Postoperative visual acuities with at least six months' follow-up range from no light perception to 20/50, with seven patients (23%) 20/400 or better.

  4. Noggin 1 overexpression in retinal progenitors affects bipolar cell generation.

    PubMed

    Messina, Andrea; Bridi, Simone; Bozza, Angela; Bozzi, Yuri; Baudet, Marie-Laure; Casarosa, Simona

    2016-01-01

    Waves of Bone Morphogenetic Proteins (BMPs) and their antagonists are present during initial eye development, but their possible roles in retinogenesis are still unknown. We have recently shown that noggin 1, a BMP antagonist, renders pluripotent cells able to differentiate into retinal precursors, and might be involved in the maintenance of retinal structures in the adult vertebrate eye. Here, we report that noggin 1, differently from noggin 2 and noggin 4, is expressed during all phases of Xenopus laevis retinal development. Gain-of-function experiments by electroporation in the optic vesicle show that overexpression of noggin 1 significantly decreases the number of bipolar cells in the inner nuclear layer of the retina, without significantly affecting the generation of the other retinal cell types. Our data suggest that BMP signaling could be involved in the differentiation of retinal progenitors into specific retinal subtypes during late phases of vertebrate retinal development. PMID:27389985

  5. An Unusual Case of Extensive Lattice Degeneration and Retinal Detachment

    PubMed Central

    Sarma, Saurabh Kumar; Basaiawmoit, Jennifer V.

    2016-01-01

    Lattice degeneration of the retina is not infrequently encountered on a dilated retinal examination and many of them do not need any intervention. We report a case of atypical lattice degeneration variant with peripheral retinal detachment. An asymptomatic 35-year-old lady with minimal refractive error was found to have extensive lattice degeneration, peripheral retinal detachment and fibrotic changes peripherally with elevation of retinal vessels on dilated retinal examination. There were also areas of white without pressure, chorioretinal scarring and retinal breaks. All the changes were limited to beyond the equator but were found to span 360 degrees. She was treated with barrage laser all around to prevent extension of the retinal detachment posteriorly. She remained stable till her latest follow-up two years after the barrage laser. This case is reported for its rarity with a discussion of the probable differential diagnoses. To the best of our knowledge, this is the first report of such findings in lattice degeneration.

  6. Retinal vascular changes are a marker for cerebral vascular diseases

    PubMed Central

    Moss, Heather E.

    2016-01-01

    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. Relation of retinal blood flow and retinal oxygen extraction during stimulation with diffuse luminance flicker

    PubMed Central

    Palkovits, Stefan; Lasta, Michael; Told, Reinhard; Schmidl, Doreen; Werkmeister, René; Cherecheanu, Alina Popa; Garhöfer, Gerhard; Schmetterer, Leopold

    2015-01-01

    Cerebral and retinal blood flow are dependent on local neuronal activity. Several studies quantified the increase in cerebral blood flow and oxygen consumption during activity. In the present study we investigated the relation between changes in retinal blood flow and oxygen extraction during stimulation with diffuse luminance flicker and the influence of breathing gas mixtures with different fractions of O2 (FiO2; 100% 15% and 12%). Twenty-four healthy subjects were included. Retinal blood flow was studied by combining measurement of vessel diameters using the Dynamic Vessel Analyser with measurements of blood velocity using laser Doppler velocimetry. Oxygen saturation was measured using spectroscopic reflectometry and oxygen extraction was calculated. Flicker stimulation increased retinal blood flow (57.7 ± 17.8%) and oxygen extraction (34.6 ± 24.1%; p < 0.001 each). During 100% oxygen breathing the response of retinal blood flow and oxygen extraction was increased (p < 0.01 each). By contrast, breathing gas mixtures with 12% and 15% FiO2 did not alter flicker–induced retinal haemodynamic changes. The present study indicates that at a comparable increase in blood flow the increase in oxygen extraction in the retina is larger than in the brain. During systemic hyperoxia the blood flow and oxygen extraction responses to neural stimulation are augmented. The underlying mechanism is unknown. PMID:26672758

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

    PubMed

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

    1995-01-01

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

  9. Retinal topography maps in R: New tools for the analysis and visualization of spatial retinal data

    PubMed Central

    Cohn, Brian A.; Collin, Shaun P.; Wainwright, Peter C.; Schmitz, Lars

    2015-01-01

    Retinal topography maps are a widely used tool in vision science, neuroscience, and visual ecology, providing an informative visualization of the spatial distribution of cell densities across the retinal hemisphere. Here, we introduce Retina, an R package for computational mapping, inspection of topographic model fits, and generation of average maps. Functions in Retina take cell count data obtained from retinal wholemounts using stereology software. Accurate visualizations and comparisons between different eyes have been difficult in the past, because of deformation and incisions of retinal wholemounts. We account for these issues by incorporation of the R package Retistruct, which results in a retrodeformation of the wholemount into a hemispherical shape, similar to the original eyecup. The maps are generated by thin plate splines, after the data were transformed into a two-dimensional space with an azimuthal equidistant plot projection. Retina users can compute retinal topography maps independent of stereology software choice and assess model fits with a variety of diagnostic plots. Functionality of Retina also includes species average maps, an essential feature for interspecific analyses. The Retina package will facilitate rigorous comparative studies in visual ecology by providing a robust quantitative approach to generate retinal topography maps. PMID:26230981

  10. Relation of retinal blood flow and retinal oxygen extraction during stimulation with diffuse luminance flicker.

    PubMed

    Palkovits, Stefan; Lasta, Michael; Told, Reinhard; Schmidl, Doreen; Werkmeister, René; Cherecheanu, Alina Popa; Garhöfer, Gerhard; Schmetterer, Leopold

    2015-01-01

    Cerebral and retinal blood flow are dependent on local neuronal activity. Several studies quantified the increase in cerebral blood flow and oxygen consumption during activity. In the present study we investigated the relation between changes in retinal blood flow and oxygen extraction during stimulation with diffuse luminance flicker and the influence of breathing gas mixtures with different fractions of O2 (FiO2; 100% 15% and 12%). Twenty-four healthy subjects were included. Retinal blood flow was studied by combining measurement of vessel diameters using the Dynamic Vessel Analyser with measurements of blood velocity using laser Doppler velocimetry. Oxygen saturation was measured using spectroscopic reflectometry and oxygen extraction was calculated. Flicker stimulation increased retinal blood flow (57.7 ± 17.8%) and oxygen extraction (34.6 ± 24.1%; p < 0.001 each). During 100% oxygen breathing the response of retinal blood flow and oxygen extraction was increased (p < 0.01 each). By contrast, breathing gas mixtures with 12% and 15% FiO2 did not alter flicker-induced retinal haemodynamic changes. The present study indicates that at a comparable increase in blood flow the increase in oxygen extraction in the retina is larger than in the brain. During systemic hyperoxia the blood flow and oxygen extraction responses to neural stimulation are augmented. The underlying mechanism is unknown. PMID:26672758

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

    SciTech Connect

    Suhai, Sandor

    2011-01-01

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

  12. Red blood cells in retinal vascular disorders.

    PubMed

    Agrawal, Rupesh; Sherwood, Joseph; Chhablani, Jay; Ricchariya, Ashutosh; Kim, Sangho; Jones, Philip H; Balabani, Stavroula; Shima, David

    2016-01-01

    Microvascular circulation plays a vital role in regulating physiological functions, such as vascular resistance, and maintaining organ health. Pathologies such as hypertension, diabetes, or hematologic diseases affect the microcirculation posing a significant risk to human health. The retinal vasculature provides a unique window for non-invasive visualisation of the human circulation in vivo and retinal vascular image analysis has been established to predict the development of both clinical and subclinical cardiovascular, metabolic, renal and retinal disease in epidemiologic studies. Blood viscosity which was otherwise thought to play a negligible role in determining blood flow based on Poiseuille's law up to the 1970s has now been shown to play an equally if not a more important role in controlling microcirculation and quantifying blood flow. Understanding the hemodynamics/rheology of the microcirculation and its changes in diseased states remains a challenging task; this is due to the particulate nature of blood, the mechanical properties of the cells (such as deformability and aggregability) and the complex architecture of the microvasculature. In our review, we have tried to postulate a possible role of red blood cell (RBC) biomechanical properties and laid down future framework for research related to hemorrheological aspects of blood in patients with retinal vascular disorders.

  13. Dynamic eye phantom for retinal oximetry measurements

    PubMed Central

    Lemaillet, Paul; Ramella-Roman, Jessica C.

    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 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. PMID:20059246

  14. Unsupervised Retinal Vessel Segmentation Using Combined Filters

    PubMed Central

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

    2016-01-01

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

  15. Genetic loci for retinal arteriolar microcirculation.

    PubMed

    Sim, Xueling; Jensen, Richard A; Ikram, M Kamran; Cotch, Mary Frances; Li, Xiaohui; MacGregor, Stuart; Xie, Jing; Smith, Albert Vernon; Boerwinkle, Eric; Mitchell, Paul; Klein, Ronald; Klein, Barbara E K; Glazer, Nicole L; Lumley, Thomas; McKnight, Barbara; Psaty, Bruce M; de Jong, Paulus T V M; Hofman, Albert; Rivadeneira, Fernando; Uitterlinden, Andre G; van Duijn, Cornelia M; Aspelund, Thor; Eiriksdottir, Gudny; Harris, Tamara B; Jonasson, Fridbert; Launer, Lenore J; Attia, John; Baird, Paul N; Harrap, Stephen; Holliday, Elizabeth G; Inouye, Michael; Rochtchina, Elena; Scott, Rodney J; Viswanathan, Ananth; Li, Guo; Smith, Nicholas L; Wiggins, Kerri L; Kuo, Jane Z; Taylor, Kent D; Hewitt, Alex W; Martin, Nicholas G; Montgomery, Grant W; Sun, Cong; Young, Terri L; Mackey, David A; van Zuydam, Natalie R; Doney, Alex S F; Palmer, Colin N A; Morris, Andrew D; Rotter, Jerome I; Tai, E Shyong; Gudnason, Vilmundur; Vingerling, Johannes R; Siscovick, David S; Wang, Jie Jin; Wong, Tien Y

    2013-01-01

    Narrow arterioles in the retina have been shown to predict hypertension as well as other vascular diseases, likely through an increase in the peripheral resistance of the microcirculatory flow. In this study, we performed a genome-wide association study in 18,722 unrelated individuals of European ancestry from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium and the Blue Mountain Eye Study, to identify genetic determinants associated with variations in retinal arteriolar caliber. Retinal vascular calibers were measured on digitized retinal photographs using a standardized protocol. One variant (rs2194025 on chromosome 5q14 near the myocyte enhancer factor 2C MEF2C gene) was associated with retinal arteriolar caliber in the meta-analysis of the discovery cohorts at genome-wide significance of P-value <5×10(-8). This variant was replicated in an additional 3,939 individuals of European ancestry from the Australian Twins Study and Multi-Ethnic Study of Atherosclerosis (rs2194025, P-value = 2.11×10(-12) in combined meta-analysis of discovery and replication cohorts). In independent studies of modest sample sizes, no significant association was found between this variant and clinical outcomes including coronary artery disease, stroke, myocardial infarction or hypertension. In conclusion, we found one novel loci which underlie genetic variation in microvasculature which may be relevant to vascular disease. The relevance of these findings to clinical outcomes remains to be determined.

  16. [Retinal detachment with retinoschisis--case report].

    PubMed

    Cristescu, R; Muşat, O; Toma, Oana; Coma, Corina; Gabej, Ioana; Burcea, M

    2013-01-01

    We present the case of a 43 year old patient diagnosed with rhegmatogenous retinal detachment and retinoschizis, a rare case of disease association. Surgery is recommended and we practice 23 gauge vitrectomy, laser retinopexy, criopexy in the periphery and internal heavy oil tamponade. Postoperatory evolution was favorable.

  17. a Review of Retinal Prosthesis Approaches

    NASA Astrophysics Data System (ADS)

    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.

  18. Unsupervised Retinal Vessel Segmentation Using Combined Filters.

    PubMed

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

    2016-01-01

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

  19. Changes in ganglion cells during retinal degeneration.

    PubMed

    Saha, Susmita; Greferath, Ursula; Vessey, Kirstan A; Grayden, David B; Burkitt, Anthony N; Fletcher, Erica L

    2016-08-01

    Inherited retinal degeneration such as retinitis pigmentosa (RP) is associated with photoreceptor loss and concomitant morphological and functional changes in the inner retina. It is not known whether these changes are associated with changes in the density and distribution of synaptic inputs to retinal ganglion cells (RGCs). We quantified changes in ganglion cell density in rd1 and age-matched C57BL/6J-(wildtype, WT) mice using the immunocytochemical marker, RBPMS. Our data revealed that following complete loss of photoreceptors, (∼3months of age), there was a reduction in ganglion cell density in the peripheral retina. We next examined changes in synaptic inputs to A type ganglion cells by performing double labeling experiments in mice with the ganglion cell reporter lines, rd1-Thy1 and age-matched wildtype-Thy1. Ribbon synapses were identified by co-labelling with CtBP2 (RIBEYE) and conventional synapses with the clustering molecule, gephyrin. ON RGCs showed a significant reduction in RIBEYE-immunoreactive synapse density while OFF RGCs showed a significant reduction in the gephyrin-immmunoreactive synapse density. Distribution patterns of both synaptic markers across the dendritic trees of RGCs were unchanged. The change in synaptic inputs to RGCs was associated with a reduction in the number of immunolabeled rod bipolar and ON cone bipolar cells. These results suggest that functional changes reported in ganglion cells during retinal degeneration could be attributed to loss of synaptic inputs. PMID:27132232

  20. Retinal Biochemistry, Physiology and Cell Biology.

    PubMed

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

    2016-01-01

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

  1. A continuum model of retinal electrical stimulation

    NASA Astrophysics Data System (ADS)

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

    2011-10-01

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

  2. The Retinitis Pigmentosa Student: Selected Aspects.

    ERIC Educational Resources Information Center

    Sullivan, Franklin N.

    1984-01-01

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

  3. A Psychophysical Test for Retinitis Pigmentosa.

    ERIC Educational Resources Information Center

    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…

  4. CERKL Knockdown Causes Retinal Degeneration in Zebrafish

    PubMed Central

    Riera, Marina; Burguera, Demian; Garcia-Fernàndez, Jordi; Gonzàlez-Duarte, Roser

    2013-01-01

    The human CERKL gene is responsible for common and severe forms of retinal dystrophies. Despite intense in vitro studies at the molecular and cellular level and in vivo analyses of the retina of murine knockout models, CERKL function remains unknown. In this study, we aimed to approach the developmental and functional features of cerkl in Danio rerio within an Evo-Devo framework. We show that gene expression increases from early developmental stages until the formation of the retina in the optic cup. Unlike the high mRNA-CERKL isoform multiplicity shown in mammals, the moderate transcriptional complexity in fish facilitates phenotypic studies derived from gene silencing. Moreover, of relevance to pathogenicity, teleost CERKL shares the two main human protein isoforms. Morpholino injection has been used to generate a cerkl knockdown zebrafish model. The morphant phenotype results in abnormal eye development with lamination defects, failure to develop photoreceptor outer segments, increased apoptosis of retinal cells and small eyes. Our data support that zebrafish Cerkl does not interfere with proliferation and neural differentiation during early developmental stages but is relevant for survival and protection of the retinal tissue. Overall, we propose that this zebrafish model is a powerful tool to unveil CERKL contribution to human retinal degeneration. PMID:23671706

  5. Dynamic eye phantom for retinal oximetry measurements

    NASA Astrophysics Data System (ADS)

    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.

  6. Photovoltaic retinal prosthesis with high pixel density

    NASA Astrophysics Data System (ADS)

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

    2012-06-01

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

  7. Genetic loci for retinal arteriolar microcirculation.

    PubMed

    Sim, Xueling; Jensen, Richard A; Ikram, M Kamran; Cotch, Mary Frances; Li, Xiaohui; MacGregor, Stuart; Xie, Jing; Smith, Albert Vernon; Boerwinkle, Eric; Mitchell, Paul; Klein, Ronald; Klein, Barbara E K; Glazer, Nicole L; Lumley, Thomas; McKnight, Barbara; Psaty, Bruce M; de Jong, Paulus T V M; Hofman, Albert; Rivadeneira, Fernando; Uitterlinden, Andre G; van Duijn, Cornelia M; Aspelund, Thor; Eiriksdottir, Gudny; Harris, Tamara B; Jonasson, Fridbert; Launer, Lenore J; Attia, John; Baird, Paul N; Harrap, Stephen; Holliday, Elizabeth G; Inouye, Michael; Rochtchina, Elena; Scott, Rodney J; Viswanathan, Ananth; Li, Guo; Smith, Nicholas L; Wiggins, Kerri L; Kuo, Jane Z; Taylor, Kent D; Hewitt, Alex W; Martin, Nicholas G; Montgomery, Grant W; Sun, Cong; Young, Terri L; Mackey, David A; van Zuydam, Natalie R; Doney, Alex S F; Palmer, Colin N A; Morris, Andrew D; Rotter, Jerome I; Tai, E Shyong; Gudnason, Vilmundur; Vingerling, Johannes R; Siscovick, David S; Wang, Jie Jin; Wong, Tien Y

    2013-01-01

    Narrow arterioles in the retina have been shown to predict hypertension as well as other vascular diseases, likely through an increase in the peripheral resistance of the microcirculatory flow. In this study, we performed a genome-wide association study in 18,722 unrelated individuals of European ancestry from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium and the Blue Mountain Eye Study, to identify genetic determinants associated with variations in retinal arteriolar caliber. Retinal vascular calibers were measured on digitized retinal photographs using a standardized protocol. One variant (rs2194025 on chromosome 5q14 near the myocyte enhancer factor 2C MEF2C gene) was associated with retinal arteriolar caliber in the meta-analysis of the discovery cohorts at genome-wide significance of P-value <5×10(-8). This variant was replicated in an additional 3,939 individuals of European ancestry from the Australian Twins Study and Multi-Ethnic Study of Atherosclerosis (rs2194025, P-value = 2.11×10(-12) in combined meta-analysis of discovery and replication cohorts). In independent studies of modest sample sizes, no significant association was found between this variant and clinical outcomes including coronary artery disease, stroke, myocardial infarction or hypertension. In conclusion, we found one novel loci which underlie genetic variation in microvasculature which may be relevant to vascular disease. The relevance of these findings to clinical outcomes remains to be determined. PMID:23776548

  8. Photovoltaic Retinal Prosthesis with High Pixel Density.

    PubMed

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

    2012-06-01

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

  9. Hybrid retinal tracking and coagulation system

    NASA Astrophysics Data System (ADS)

    Wright, Cameron H. G.; Oberg, Erik D.; Barrett, Steven F.

    1998-06-01

    Laser photocoagulation is used extensively by ophthalmologists to treat retinal disorders such as diabetic retinopathy and retinal breaks and tears. Currently, the procedure is performed manually and suffers from several drawbacks: it often requires many clinical visits, it is very tedious for both patient and physician, the laser pointing accuracy and safety margin are limited by a combination of the physician's manual dexterity and the patient's ability to hold their eye still, and there is a wide variability in retinal tissue absorption parameters. A computer-assisted hybrid system is under development that will rapidly and safely place multiple therapeutic lesions at desired locations on the retina in a matter of seconds. In the past, one of the main obstacles to such a system has been the ability to track the retina and compensate for any movement with sufficient speed during photocoagulation. Two different tracking modalities (digital image-based tracking and analog confocal tracking) were designed and tested in vivo on pigmented rabbits. These two systems are being seamlessly combined into a hybrid system which provides real-time, motion stabilized lesion placement for typical irradiation times (100 ms). This paper will detail the operation of the hybrid system and efforts toward controlling the depth of coagulation on the retinal surface.

  10. Nanoengineering of therapeutics for retinal vascular disease.

    PubMed

    Gahlaut, Nivriti; Suarez, Sandra; Uddin, Md Imam; Gordon, Andrew Y; Evans, Stephanie M; Jayagopal, Ashwath

    2015-09-01

    Retinal vascular diseases, including diabetic retinopathy, neovascular age related macular degeneration, and retinal vein occlusion, are leading causes of blindness in the Western world. These diseases share several common disease mechanisms, including vascular endothelial growth factor (VEGF) signaling, hypoxia, and inflammation, which provide opportunities for common therapeutic strategies. Treatment of these diseases using laser therapy, anti-VEGF injections, and/or steroids has significantly improved clinical outcomes. However, these strategies do not address the underlying root causes of pathology, and may have deleterious side effects. Furthermore, many patients continue to progress toward legal blindness despite receiving regular therapy. Nanomedicine, the engineering of therapeutics at the 1-100 nm scale, is a promising approach for improving clinical management of retinal vascular diseases. Nanomedicine-based technologies have the potential to revolutionize the treatment of ophthalmology, through enabling sustained release of drugs over several months, reducing side effects due to specific targeting of dysfunctional cells, and interfacing with currently "undruggable" targets. We will discuss emerging nanomedicine-based applications for the treatment of complications associated with retinal vascular diseases, including angiogenesis and inflammation.

  11. Photovoltaic Retinal Prosthesis with High Pixel Density

    PubMed Central

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

    2012-01-01

    Retinal degenerative diseases lead to blindness due to loss of the “image capturing” photoreceptors, while neurons in the “image processing” inner retinal layers are relatively well preserved. Electronic retinal prostheses seek to restore sight by electrically stimulating surviving neurons. Most implants are powered through inductive coils, requiring complex surgical methods to implant the coil-decoder-cable-array systems, which deliver energy to stimulating electrodes via intraocular cables. We present a photovoltaic subretinal prosthesis, in which silicon photodiodes in each pixel receive power and data directly through pulsed near-infrared illumination and electrically stimulate neurons. Stimulation was produced in normal and degenerate rat retinas, with pulse durations from 0.5 to 4 ms, and threshold peak irradiances from 0.2 to 10 mW/mm2, two orders of magnitude below the ocular safety limit. Neural responses were elicited by illuminating a single 70 μm bipolar pixel, demonstrating the possibility of a fully-integrated photovoltaic retinal prosthesis with high pixel density. PMID:23049619

  12. Retinal pigment epithelial hamartoma--unusual manifestations.

    PubMed Central

    Rosenberg, P. R.; Walsh, J. B.

    1984-01-01

    Hamartoma of the retinal pigment epithelium is an uncommon tumour of young adults. We have seen 2 patients with this clinical diagnosis, both with unusual manifestations. In one patient growth of the tumour was observed over a 5-year period. In the second patient arterial-arterial anastomoses were detected at a site distal to the tumour. Images PMID:6722077

  13. Prospectives for Gene Therapy of Retinal Degenerations

    PubMed Central

    Thumann, Gabriele

    2012-01-01

    Retinal degenerations encompass a large number of diseases in which the retina and associated retinal pigment epithelial (RPE) cells progressively degenerate leading to severe visual disorders or blindness. Retinal degenerations can be divided into two groups, a group in which the defect has been linked to a specific gene and a second group that has a complex etiology that includes environmental and genetic influences. The first group encompasses a number of relatively rare diseases with the most prevalent being Retinitis pigmentosa that affects approximately 1 million individuals worldwide. Attempts have been made to correct the defective gene by transfecting the appropriate cells with the wild-type gene and while these attempts have been successful in animal models, human gene therapy for these inherited retinal degenerations has only begun recently and the results are promising. To the second group belong glaucoma, age-related macular degeneration (AMD) and diabetic retinopathy (DR). These retinal degenerations have a genetic component since they occur more often in families with affected probands but they are also linked to environmental factors, specifically elevated intraocular pressure, age and high blood sugar levels respectively. The economic and medical impact of these three diseases can be assessed by the number of individuals affected; AMD affects over 30 million, DR over 40 million and glaucoma over 65 million individuals worldwide. The basic defect in these diseases appears to be the relative lack of a neurogenic environment; the neovascularization that often accompanies these diseases has suggested that a decrease in pigment epithelium-derived factor (PEDF), at least in part, may be responsible for the neurodegeneration since PEDF is not only an effective neurogenic and neuroprotective agent but also a potent inhibitor of neovascularization. In the last few years inhibitors of vascularization, especially antibodies against vascular endothelial cell

  14. Clinical effects and safety of treating diabetic macular edema with intravitreal injection of ranibizumab combined with retinal photocoagulation

    PubMed Central

    Yan, Panshi; Qian, Cheng; Wang, Wenzhan; Dong, Yi; Wan, Guangming; Chen, Yue

    2016-01-01

    Background This study was designed to examine the clinical effects of treating diabetic macular edema with an intravitreal injection of ranibizumab in combination with retinal photocoagulation. Methods Sixty-two cases (75 eyes) with confirmed severe proliferative diabetic retinopathy or proliferative diabetic retinopathy in combination with macular edema were randomly divided into the observation group (37 eyes were given an intravitreal injection of ranibizumab combined with retinal photocoagulation) and the control group (38 eyes received retinal photocoagulation only). Vision, fundus condition, central macular thickness, and the macular leakage area were recorded before and after treatment. Results The best-corrected visual acuity and macular leakage area were similar between the observation and control groups (P>0.05). The best-corrected visual acuity in the observation group was higher than that in the control group 3 and 6 months after treatment (P<0.05) and showed a rising tendency. The macular leakage area in the observation group was significantly lower than that in the control group 1 and 3 months after treatment (P<0.05). However, the macular leakage area was similar 6 months after treatment (P>0.05). The central macular thickness of the observation group was lower than that in the control group 1, 3, and 6 months after treatment (P<0.05). The laser energy used in the observation group was also smaller than that in the control group (P<0.05). The intraocular pressure was not significantly different between the groups (P<0.05). No patients in the two groups developed eye or systemic complications, such as glaucoma, cataract, or vitreous hemorrhage during treatment. Conclusion Intravitreal injection of ranibizumab combined with retinal photocoagulation was proven to be effective in treating diabetic macular edema as it improved vision and resulted in fewer complications. PMID:27103811

  15. Photovoltaic retinal prosthesis: implant fabrication and performance

    NASA Astrophysics Data System (ADS)

    Wang, Lele; Mathieson, K.; Kamins, T. I.; Loudin, J. D.; Galambos, L.; Goetz, G.; Sher, A.; Mandel, Y.; Huie, P.; Lavinsky, D.; Harris, J. S.; Palanker, D. V.

    2012-08-01

    The objective of this work is to develop and test a photovoltaic retinal prosthesis for restoring sight to patients blinded by degenerative retinal diseases. A silicon photodiode array for subretinal stimulation has been fabricated by a silicon-integrated-circuit/MEMS process. Each pixel in the two-dimensional array contains three series-connected photodiodes, which photovoltaically convert pulsed near-infrared light into bi-phasic current to stimulate nearby retinal neurons without wired power connections. The device thickness is chosen to be 30 µm to absorb a significant portion of light while still being thin enough for subretinal implantation. Active and return electrodes confine current near each pixel and are sputter coated with iridium oxide to enhance charge injection levels and provide a stable neural interface. Pixels are separated by 5 µm wide trenches to electrically isolate them and to allow nutrient diffusion through the device. Three sizes of pixels (280, 140 and 70 µm) with active electrodes of 80, 40 and 20 µm diameter were fabricated. The turn-on voltages of the one-diode, two-series-connected diode and three-series-connected diode structures are approximately 0.6, 1.2 and 1.8 V, respectively. The measured photo-responsivity per diode at 880 nm wavelength is ˜0.36 A W-1, at zero voltage bias and scales with the exposed silicon area. For all three pixel sizes, the reverse-bias dark current is sufficiently low (<100 pA) for our application. Pixels of all three sizes reliably elicit retinal responses at safe near-infrared light irradiances, with good acceptance of the photodiode array in the subretinal space. The fabricated device delivers efficient retinal stimulation at safe near-infrared light irradiances without any wired power connections, which greatly simplifies the implantation procedure. Presence of the return electrodes in each pixel helps to localize the current, and thereby improves resolution.

  16. Vitreal Oxygenation in Retinal Ischemia Reperfusion

    PubMed Central

    Abdallah, Walid; Ameri, Hossein; Barron, Ernesto; Chader, Gerald J.; Greenbaum, Elias; Hinton, David R.

    2011-01-01

    Purpose. To study the feasibility of anterior vitreal oxygenation for the treatment of acute retinal ischemia. Methods. Twenty rabbits were randomized into an oxygenation group, a sham treatment group, and a no treatment group. Baseline electroretinography (ERG) and preretinal oxygen (Po2) measurements were obtained 3 to 5 days before surgery. Intraocular pressure was raised to 100 mm Hg for 90 minutes and then normalized. The oxygenation group underwent vitreal oxygenation for 30 minutes using intravitreal electrodes. The sham treatment group received inactive electrodes for 30 minutes while there was no intervention for the no treatment group. Preretinal Po2 in the posterior vitreous was measured 30 minutes after intervention or 30 minutes after reperfusion (no treatment group) and on postoperative days (d) 3, 6, 9, and 12. On d14, rabbits underwent ERG and were euthanatized. Results. Mean final (d12) Po2 was 10.64 ± 0.77 mm Hg for the oxygenation group, 2.14 ± 0.61 mm Hg for the sham group, and 1.98 ± 0.63 mm Hg for the no treatment group. On ERG, scotopic b-wave amplitude was significantly preserved in the oxygenation group compared with the other two groups. Superoxide dismutase assay showed higher activity in the operated eyes than in the nonoperated control eyes in the sham treatment group and no treatment group only. Histopathology showed preservation of retinal architecture and choroidal vasculature in the oxygenation group, whereas the sham-treated and nontreated groups showed retinal thinning and choroidal atrophy. Conclusions. In severe total ocular ischemia, anterior vitreal oxygenation supplies enough oxygen to penetrate the retinal thickness, resulting in rescue of the RPE/choriocapillaris that continues to perfuse, hence sparing the retinal tissue from damage. PMID:21051734

  17. Interphotoreceptor matrix components in retinal cell transplants.

    PubMed

    Juliusson, B; Mieziewska, K; Bergström, A; Wilke, K; Van Veen, T; Ehinger, B

    1994-05-01

    To further investigate the functional potential of retinal transplants we have used immunocytochemistry to study the distribution of four different interphotoreceptor matrix (IPM)-specific components in rabbit retinal transplants. The different components were: interphotoreceptor retinoid-binding protein (IRBP), chondroitin-6-sulfate, F22 antigen and peanut agglutinin (PNA) binding structures. IRBP acts as a retinoid-transport protein between the neural retina and the retinal pigment epithelium. Chondroitin-6-sulfate is a glycosaminoglycan and a part of the insoluble IPM skeleton. The identity and role of the F22 antigen is not known. However, it is a 250 kDa protein localized to specific extracellular compartments such as teh IPM. PNA is a lectin with a high binding affinity for D-galactose-beta (1-3) N-acetyl-D-galactosamine disaccharide linkages and binds to IPM domains surrounding cones, but not rods. The transplants (15-day-old embryonic rabbit retina) were placed between the neural retina and retinal pigment epithelium in adult hosts. The transplants developed the typical rosette formations with photoreceptors toward the center. IRBP labeling was distinct in the IPM in the host retina. However, no IRBP labeling could be detected in the transplants. The chondroitin-6-sulfate and F22 antibodies strongly labeled the IPM in the host retina and corresponding structures in the center of rosettes. A cone-specific labeling with PNA could be seen in the host retina. In the transplants, however, PNA labeling appeared in association with many more photoreceptors than in the host retina. There is no previous study available on the IPM in retinal cell transplants.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Retinal and Choroidal Folds in Papilledema

    PubMed Central

    Sibony, Patrick A.; Kupersmith, Mark J.; Feldon, Steven E.; Wang, Jui-Kai; Garvin, Mona

    2015-01-01

    Purpose To determine the frequency, patterns, associations, and biomechanical implications of retinal and choroidal folds in papilledema due to idiopathic intracranial hypertension (IIH). Methods Retinal and choroidal folds were studied in patients enrolled in the IIH Treatment Trial using fundus photography (n = 165 study eyes) and spectral-domain optical coherence tomography (SD-OCT; n = 125). We examined the association between folds and peripapillary shape, retinal nerve fiber layer (RNFL) thickness, disc volume, Frisén grade, acuity, perimetric mean deviation, intraocular pressure, intracranial pressure, and refractive error. Results We identified three types of folds in IIH patients with papilledema: peripapillary wrinkles (PPW), retinal folds (RF), and choroidal folds (CF). Frequency, with photos, was 26%, 19%, and 1%, respectively; SD-OCT frequency was 46%, 47%, and 10%. At least one type of fold was present in 41% of patients with photos and 73% with SD-OCT. Spectral-domain OCT was more sensitive. Structural parameters related to the severity of papilledema were associated with PPW and RF, whereas anterior deformation of the peripapillary RPE/basement membrane layer was associated with CF and RF. Folds were not associated with vision loss at baseline. Conclusions Folds in papilledema are biomechanical signs of stress/strain on the optic nerve head and load-bearing structures induced by intracranial hypertension. Folds are best imaged with SD-OCT. The patterns of retinal and choroidal folds are the products of a complex interplay between the degree of papilledema and anterior deformation of the load-bearing structures (sclera and possibly the lamina cribrosa), both modulated by structural geometry and material properties of the optic nerve head. (ClinicalTrials.gov number, NCT01003639.) PMID:26335066

  19. Photovoltaic retinal prosthesis: implant fabrication and performance.

    PubMed

    Wang, Lele; Mathieson, K; Kamins, T I; Loudin, J D; Galambos, L; Goetz, G; Sher, A; Mandel, Y; Huie, P; Lavinsky, D; Harris, J S; Palanker, D V

    2012-08-01

    The objective of this work is to develop and test a photovoltaic retinal prosthesis for restoring sight to patients blinded by degenerative retinal diseases. A silicon photodiode array for subretinal stimulation has been fabricated by a silicon-integrated-circuit/MEMS process. Each pixel in the two-dimensional array contains three series-connected photodiodes, which photovoltaically convert pulsed near-infrared light into bi-phasic current to stimulate nearby retinal neurons without wired power connections. The device thickness is chosen to be 30 µm to absorb a significant portion of light while still being thin enough for subretinal implantation. Active and return electrodes confine current near each pixel and are sputter coated with iridium oxide to enhance charge injection levels and provide a stable neural interface. Pixels are separated by 5 µm wide trenches to electrically isolate them and to allow nutrient diffusion through the device. Three sizes of pixels (280, 140 and 70 µm) with active electrodes of 80, 40 and 20 µm diameter were fabricated. The turn-on voltages of the one-diode, two-series-connected diode and three-series-connected diode structures are approximately 0.6, 1.2 and 1.8 V, respectively. The measured photo-responsivity per diode at 880 nm wavelength is ∼0.36 A W(-1), at zero voltage bias and scales with the exposed silicon area. For all three pixel sizes, the reverse-bias dark current is sufficiently low (<100 pA) for our application. Pixels of all three sizes reliably elicit retinal responses at safe near-infrared light irradiances, with good acceptance of the photodiode array in the subretinal space. The fabricated device delivers efficient retinal stimulation at safe near-infrared light irradiances without any wired power connections, which greatly simplifies the implantation procedure. Presence of the return electrodes in each pixel helps to localize the current, and thereby improves resolution.

  20. Retinal Prosthesis System for Advanced Retinitis Pigmentosa: A Health Technology Assessment

    PubMed Central

    2016-01-01

    Background Retinitis pigmentosa is a group of genetic disorders that involves the breakdown and loss of photoreceptors in the retina, resulting in progressive retinal degeneration and eventual blindness. The Argus II Retinal Prosthesis System is the only currently available surgical implantable device approved by Health Canada. It has been shown to improve visual function in patients with severe visual loss from advanced retinitis pigmentosa. The objective of this analysis was to examine the clinical effectiveness, cost-effectiveness, budget impact, and safety of the Argus II system in improving visual function, as well as exploring patient experiences with the system. Methods We performed a systematic search of the literature for studies examining the effects of the Argus II retinal prosthesis system in patients with advanced retinitis pigmentosa, and appraised the evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria, focusing on visual function, functional outcomes, quality of life, and adverse events. We developed a Markov decision-analytic model to assess the cost-effectiveness of the Argus II system compared with standard care over a 10-year time horizon. We also conducted a 5-year budget impact analysis. We used a qualitative design and an interview methodology to examine patients’ lived experience, and we used a modified grounded theory methodology to analyze information from interviews. Transcripts were coded, and themes were compared against one another. Results One multicentre international study and one single-centre study were included in the clinical review. In both studies, patients showed improved visual function with the Argus II system. However, the sight-threatening surgical complication rate was substantial. In the base-case analysis, the Argus II system was cost-effective compared with standard care only if willingness-to-pay was more than $207,616 per quality-adjusted life

  1. Superficial siderosis is a warning sign for future intracranial hemorrhage.

    PubMed

    Linn, Jennifer; Wollenweber, Frank A; Lummel, Nina; Bochmann, Katja; Pfefferkorn, Thomas; Gschwendtner, Andreas; Bruckmann, Hartmut; Dichgans, Martin; Opherk, Christian

    2013-01-01

    Supratentorial superficial siderosis (SS) is a frequent imaging marker of cerebral amyloid angiopathy (CAA). It is most probably caused by focal subarachnoid hemorrhages (fSAHs). Based on single-case observations, it has been proposed that such fSAHs might be a predisposing factor for future intracranial hemorrhage. Here we tested the hypothesis if a SS as a residue of fSAHs must be regarded as a warning sign for future intracranial hemorrhage. Fifty-one consecutive patients with SS and no apparent cause other than possible or probable CAA were identified through a database search and followed-up for a median interval of 35.3 months (range 6-120 months). Main outcome measures were rate and location of new intracranial hemorrhages. Twenty-four patients (47.1 %) had experienced any new intracranial hemorrhage, 18 patients (35.3 %) had an intracerebral hemorrhage (ICH), and in 13 of them (25.5 %), the hemorrhage was located at the site of pre-existing siderosis. Six patients (11.7 %) had developed a new subarachnoid hemorrhage (SAH), four of them at the site of siderosis. Patients with SS are at substantial risk for subsequent intracranial hemorrhage. SS can be considered a warning sign of future ICH or SAH, which frequently occur adjacent to pre-existing SS. Prospective studies are needed to confirm these findings.

  2. Spontaneous primary intraventricular hemorrhage: clinical features and early outcome.

    PubMed

    Arboix, Adrià; García-Eroles, Luis; Vicens, Adela; Oliveres, Montserrat; Massons, Joan

    2012-01-01

    Purpose. Primary hemorrhage in the ventricular system without a recognizable parenchymal component is very rare. This single-center retrospective study aimed to further characterize the clinical characteristics and early outcome of this stroke subtype. Methods. All patients with primary intraventricular hemorrhage included in a prospective hospital-based stroke registry over a 19-year period were assessed. A standardized protocol with 161 items, including demographics, risk factors, clinical data, neuroimaging findings, and outcome, was used for data collection. A comparison was made between the groups of primary intraventricular hemorrhage and subcortical intracerebral hemorrhage. Predictors of primary intraventricular hemorrhage were identified by logistic regression analysis. Results. There were 12 patients with primary intraventricular hemorrhage (0.31% of all cases of stroke included in the database) and 133 in the cohort of subcortical hemorrhage. Very old age (≥85 years) (odds ratio (OR) 9.89), atrial fibrillation (OR 8.92), headache (OR 6.89), and altered consciousness (OR 4.36) were independent predictors of intraventricular hemorrhage. The overall in-hospital mortality rate was 41.7% (5/12) but increased to 60% (3/5) in patients aged 85 years or older. Conclusion. Although primary intraventricular hemorrhage is uncommon, it is a severe clinical condition with a high early mortality. The prognosis is particularly poor in very old patients.

  3. Spontaneous Primary Intraventricular Hemorrhage: Clinical Features and Early Outcome

    PubMed Central

    Arboix, Adrià; García-Eroles, Luis; Vicens, Adela; Oliveres, Montserrat; Massons, Joan

    2012-01-01

    Purpose. Primary hemorrhage in the ventricular system without a recognizable parenchymal component is very rare. This single-center retrospective study aimed to further characterize the clinical characteristics and early outcome of this stroke subtype. Methods. All patients with primary intraventricular hemorrhage included in a prospective hospital-based stroke registry over a 19-year period were assessed. A standardized protocol with 161 items, including demographics, risk factors, clinical data, neuroimaging findings, and outcome, was used for data collection. A comparison was made between the groups of primary intraventricular hemorrhage and subcortical intracerebral hemorrhage. Predictors of primary intraventricular hemorrhage were identified by logistic regression analysis. Results. There were 12 patients with primary intraventricular hemorrhage (0.31% of all cases of stroke included in the database) and 133 in the cohort of subcortical hemorrhage. Very old age (≥85 years) (odds ratio (OR) 9.89), atrial fibrillation (OR 8.92), headache (OR 6.89), and altered consciousness (OR 4.36) were independent predictors of intraventricular hemorrhage. The overall in-hospital mortality rate was 41.7% (5/12) but increased to 60% (3/5) in patients aged 85 years or older. Conclusion. Although primary intraventricular hemorrhage is uncommon, it is a severe clinical condition with a high early mortality. The prognosis is particularly poor in very old patients. PMID:22966468

  4. A case of spontaneous perirenal hemorrhage secondary to polyarteritis nodosa.

    PubMed

    Nguan, Christopher; Leone, Ercole

    2002-12-01

    A case report of a patient who develops a spontaneous perinephric hemorrhage secondary to polyarteritis nodosa (PAN) is described. The diagnosis of PAN was delayed in this patient somewhat due to a previously unrecognized relation to a recent perihepatic hemorrhage. Unenhanced CT findings in this case were nonspecific, but follow up angiography demonstrated characteristic subsegmental and interlobular renal artery aneurysms. Spontaneous perinephric hemorrhage is an uncommon complication of PAN however an elevated level of suspicion regarding the diagnosis of a systemic vasculitis should be considered in any case of spontaneous renal, hepatic, or gastrointestinal hemorrhage.

  5. Examination of postmortem retinal folds: A non-invasive study.

    PubMed

    Oshima, Toru; Yoshikawa, Hiroshi; Ohtani, Maki; Mimasaka, Sohtaro

    2015-02-01

    The postmortem retinal fold has been previously documented, but its mechanism of formation is not known. All previous studies of the fold involved invasive techniques and the postmortem ocular fundus has yet to be non-invasively examined. Our study used the non-invasive techniques of monocular indirect ophthalmoscopy and ocular echography to examine 79 postmortem eyes of 42 bodies. We examined whether the postmortem retinal fold was associated with postmortem time, position, and/or age. Age was significantly associated with postmortem retinal fold formation (Mann-Whitney U test, P = 0.013), which led us to examine the effect of posterior vitreous detachment (PVD) on retinal folds. The absence of a PVD was statistically associated with the presence of a retinal fold (Fisher's exact test, P < 0.0001). Interestingly, the presence of a PVD was also significantly correlated with retinal fold height (Mann-Whitney U test, P < 0.0001). Therefore, we hypothesized that retinal folds result from postmortem vitreoretinal traction caused by eyeball flaccidity. We also believe that the loss of retinochoroidal hydrostatic pressure plays a role. It is important that forensic pathologists not confuse a postmortem retinal fold with traumatic retinal detachment or perimacular retinal folds caused by child abuse. When child abuse is suspected, forensic pathologists should perform enucleation and a subsequent histological examination for confirmation. PMID:25623189

  6. Prophylactic treatment of retinal breaks--a systematic review.

    PubMed

    Blindbaek, Søren; Grauslund, Jakob

    2015-02-01

    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.

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

    PubMed

    Greferath, Ursula; Anderson, Emily E; Jobling, Andrew I; Vessey, Kirstan A; Martinez, Gemma; de Iongh, Robb U; Kalloniatis, Michael; Fletcher, Erica L

    2015-01-01

    While photoreceptor loss is the most devastating result of inherited retinal degenerations such as retinitis pigmentosa, inner retinal neurons also undergo significant alteration. Detailing these changes has become important as many vision restorative therapies target the remaining neurons. In this study, the rd1-Fos-Tau-LacZ (rd1-FTL) mouse model was used to explore inner retinal change at a late stage of retinal degeneration, after the loss of photoreceptor nuclei. The rd1-FTL model carries a mutation in the phosphodiesterase gene, Pde6b, and an axonally targeted transgenic beta galactosidase reporter system under the control of the c-fos promoter. Retinae of transgenic rd1-FTL mice and control FTL animals aged 2-12 months were processed for indirect fluorescence immunocytochemistry. At 2 months of age, a time when the majority of photoreceptor nuclei are lost, there was negligible c-fos reporter (FTL) expression, however, from 4 months, reporter expression was observed to increase within subpopulations of amacrine and ganglion cells within the central retina. These areas of inner retinal FTL expression coincided with regions that contained aberrant Müller cells. Specifically, these cells exhibited reduced glutamine synthetase and Kir4.1 immunolabelling, whilst showing evidence of proliferative gliosis (increased cyclinD1 and glial fibrillary acidic protein expression). These changes were limited to distinct regions where cone photoreceptor terminals were absent. Overall, these results highlight that distinct areas of the rd1-FTL central retina undergo significant glial alterations after cone photoreceptor loss. These areas coincide with up-regulation of the c-fos reporter in the inner retina, which may represent a change in neuronal function/plasticity. The rd1-FTL mouse is a useful model system to probe changes that occur in the inner retina at later stages of retinal degeneration. PMID:26283925

  8. Optic Disc Hemorrhage Is Related to Various Hemodynamic Findings by Disc Angiography

    PubMed Central

    Park, Hae Young Lopilly; Jeong, Hyun Jin; Kim, Yoon Hee; Park, Chan Kee

    2015-01-01

    Background To investigate the hemodynamic characteristics of glaucoma eyes with disc hemorrhage (DH) by disc fluorescein angiography, and its relationship with glaucomatous changes of the optic disc and surrounding retinal nerve fiber layer (RNFL). Methods This study included 35 glaucoma eyes with DH who were followed up at least 5 years and had DH at presentation. Eyes were classified as eyes with DH at the border of localized RNFL defects and eyes with DH not related to localized RNFL defects. Prevalence of DH and location of the proximal border were recorded from disc photographs. Fluorescein angiography was performed 3 months after detecting the DH. Arm-retina time, arteriovenous transit time, disc filling time, choroidal filling time, and venous filling time were measured as retinal circulation parameters. The presence of disc filling defects and disc leaks were evaluated. Results There were 19 (54.3%) eyes with DH accompanying localized RNFL defects. The arm-retina time was prolonged in eyes with DH not related to RNFL defects (P = 0.044) and the arteriovenous transit time was prolonged in eyes with DH accompanying RNFL defects (P = 0.029). Among eyes with DH accompanying RNFL defects, 11 (57.9%) had vessel filling defects or delayed filling indicating blood flow stasis at the cup margin proximal to where DH occurred. Eyes with DH not related to RNFL defects did not show vessel filling defects or delayed filling. Conclusions and Relevance Eyes with DH related to RNFL defects showed prolonged arteriovenous transit time and had frequent vessel filling defects or delayed filling indicating blood flow stasis and thrombus formation at the site DH occurred. These findings suggest that vascular and hemodynamic changes due to glaucomatous structural changes cause DH in relation to localized RNFL defects. PMID:25879852

  9. Leakage Sign for Primary Intracerebral Hemorrhage

    PubMed Central

    Hirohata, Masaru; Nakamura, Yukihiko; Takeshige, Nobuyuki; Aoki, Takachika; Hattori, Gousuke; Sakata, Kiyohiko; Abe, Toshi; Uchiyama, Yuusuke; Sakamoto, Teruo; Morioka, Motohiro

    2016-01-01

    Background and Purpose— Recent studies of intracerebral hemorrhage treatments have highlighted the need to identify reliable predictors of hematoma expansion. Several studies have suggested that the spot sign on computed tomographic angiography (CTA) is a sensitive radiological predictor of hematoma expansion in the acute phase. However, the spot sign has low sensitivity for hematoma expansion. In this study, we evaluated the usefulness of a novel predictive method, called the leakage sign. Methods— We performed CTA for 80 consecutive patients presenting with spontaneous intracerebral hemorrhage. Two scans were completed: CTA phase and delayed phase (5 minutes after the CTA phase). By comparing the CTA phase images, we set a region of interest with a 10-mm diameter and calculated the Hounsfield units. We defined a positive leakage sign as a >10% increase in Hounsfield units in the region of interest. Additionally, hematoma expansion was determined on plain computed tomography at 24 hours in patients who did not undergo emergent surgery. Results— Positive spot signs and leakage signs were present in 18 (22%) patients and 35 (43%) patients, respectively. The leakage sign had higher sensitivity (93.3%) and specificity (88.9%) for hematoma expansion than the spot sign. The leakage sign, but not the spot sign, was significantly related with poor outcomes (severely disabled, vegetative state, and death) in all of the patients (P=0.03) and in patients with a hemorrhage in the putamen (P=0.0016). Conclusions— The results indicate that the leakage sign is a useful and sensitive method to predict hematoma expansion. PMID:26931155

  10. Intercellular Cross-talk in Intracerebral Hemorrhage

    PubMed Central

    Egashira, Yusuke; Hua, Ya; Keep, Richard F.; Xi, Guohua

    2015-01-01

    Intracerebral hemorrhage (ICH) is a devastating cerebrovascular disorder with high mortality and morbidity. Currently, there are few treatment strategies for ICH-induced brain injury. A recent increase in interest in the pathophysiology of ICH, has led to elucidation of the pathways underlying ICH-induced brain injury, pathways where intercellular and hematoma to cell signaling play important roles. In this review, we summarize recent advances in ICH research focusing on intercellular and hematoma:cell cross-talk related to brain injury and recovery after ICH. PMID:25863131

  11. Hemorrhage Near Fetal Rat Bone: Preliminary Results

    NASA Astrophysics Data System (ADS)

    Bigelow, Timothy A.; Miller, Rita J.; Blue, James P.; O'Brien, William D.

    2006-05-01

    High-intensity ultrasound has shown potential in treating many ailments requiring noninvasive tissue necrosis. However, little work has been done on using ultrasound to ablate pathologies on or near the developing fetus. For example, Congenital Cystic Adenomatoid Malformation (cyst on lungs), Sacrococcygeal Teratoma (benign tumor on tail bone), and Twin-Twin Transfusion Syndrome (one twin pumps blood to other twin) are selected problems that will potentially benefit from noninvasive ultrasound treatments. Before these applications can be explored, potential ultrasound-induced bioeffects should be understood. Specifically, ultrasound-induced hemorrhage near the fetal rat skull was investigated. An f/1 spherically focused transducer (5.1-cm focal length) was used to expose the skull of 18- to 19-day-gestation exteriorized rat fetuses. The ultrasound pulse had a center frequency of 0.92 MHz and pulse duration of 9.6 μs. The fetuses were exposed to 1 of 4 exposure conditions (denoted A, B, C, and D) in addition to a sham exposure. Three of the exposures consisted of a peak compressional pressure of 10 MPa, a peak rarefactional pressure of 6.7 MPa, and pulse repetition frequencies of 100 Hz (A), 250 Hz (B), and 500 Hz (C), corresponding to time-average intensities of 1.9 W/cm2, 4.7 W/cm2, and 9.4 W/cm2, respectively. Exposure D consisted of a peak compressional pressure of 6.7 MPa, a peak rarefactional pressure of 5.0 MPa, and a PRF of 500 Hz corresponding to a time-average intensity of 4.6 W/cm2. Hemorrhage occurrence increased slightly with increasing time-average intensity (i.e., 11% for A, 28% for B, 31% for C, and 19% for D with a 9% occurrence when the fetuses were not exposed). The low overall occurrence of hemorrhaging may be attributed to fetal motion (observed in over half of the fetuses from the backscattered echo during the exposure). The mean hemorrhage sizes were 3.1 mm2 for A, 2.5 mm2 for B, 2.7 mm2 for C, and 5.1 mm2 for D. The larger lesions at D may

  12. Spontaneous labyrinthine hemorrhage in sickle cell disease.

    PubMed

    Whitehead, R E; MacDonald, C B; Melhem, E R; McMahon, L

    1998-09-01

    We report the clinical and MR imaging findings in two African-American patients with manifestations of sickle cell disease affecting the inner ear. Both suffered sudden-onset sensorineural hearing loss and vestibular symptoms, and both had high labyrinthine signal on T1-weighted MR images attributed to labyrinthine hemorrhage. Follow-up studies of the first patient revealed a decrease in abnormal vestibular signal. Careful attention to the labyrinth on T1-weighted MR images can reveal vestibulocochlear clinical findings in sickle cell patients, with important implications for management and prognosis. PMID:9763373

  13. Anterior ethmoidal artery aneurysm and intracerebral hemorrhage.

    PubMed

    da Costa, L B; Valiante, T; Terbrugge, K; Tymianski, M

    2006-09-01

    The association between the formation of intracranial aneurysms and situations of increased blood flow in certain areas of the brain is well accepted today. It has been seen in association with arteriovenous malformations of the brain, carotid occlusion, and Moyamoya disease. The occurrence of aneurysms in small arteries of the skull base, with the exception of the intracavernous carotid artery, however, is rare. We report a case of a 55-year-old woman who presented with an intracerebral hemorrhage caused by a ruptured anterior ethmoidal artery aneurysm. To the best of our knowledge, this is only the second case of documented intracranial bleeding from such a lesion.

  14. Fatal dengue hemorrhagic fever imported into Germany.

    PubMed

    Schmidt-Chanasit, J; Tenner-Racz, K; Poppert, D; Emmerich, P; Frank, C; Dinges, C; Penning, R; Nerlich, A; Racz, P; Günther, S

    2012-08-01

    Dengue virus (DENV) is an arthropod-borne virus (family Flaviviridae) causing dengue fever or dengue hemorrhagic fever. Here, we report the first fatal DENV infection imported into Germany. A female traveler was hospitalized with fever and abdominal pain after returning from Ecuador. Due to a suspected acute acalculous cholecystitis, cholecystectomy was performed. After cholecystectomy, severe spontaneous bleeding from the abdominal wound occurred and the patient died. Postmortem analysis of transudate and tissue demonstrated a DENV secondary infection of the patient and a gallbladder wall thickening (GBWT) due to an extensive edema.

  15. Dengue hemorrhagic fever in Thai society.

    PubMed

    Kantachuvessiri, Aree

    2002-03-01

    Dengue hemorrhagic fever (DHF) is one of the most important infectious diseases in Thailand for many decades. Knowledge of DHF is vital to its control. Like other tropical countries, Thailand is facing this resurgent disease. The Thai National Dengue Prevention and Control Plan has been recently implemented to prevent and reduce the problems resulting from the spread of DHF. In this paper, a three-pronged strategy is offered that will create social mobilization at family, community, and national level and that will, therefore, reduce the socioeconomic and health impacts of DHF.

  16. Spontaneous retroperitoneal hemorrhage from a ruptured hypernephroma.

    PubMed

    Trivedi, R; Levy, M; Ibrahim, I; Bonacarti, A

    1979-01-01

    The clinical presentation and roentgenographic findings of renal cell carcinoma have been consistently variable. These patients can appear with flank pain mimicking ureteral colic, flank tumors, or symptomatic metastasis [1]. Systemic cardiac manifestations including cardiomegaly with congestive heart failure due to arteriovenous fistula formation have been reported [2] Roentgenographic findings may show the tumor to be either vascular or avascular. It may present as a spontaneous perforation of the pelvic ureteral system which is demonstrated by intravenous pyelography (3). In this article, we describe a case of hypernephroma in a cyst wall causing severe spontaneous hemorrhage in the retroperitoneal space resulting in a state of hypovolemic shock.

  17. Genes and environment in neonatal intraventricular hemorrhage.

    PubMed

    Ment, Laura R; Ådén, Ulrika; Bauer, Charles R; Bada, Henrietta S; Carlo, Waldemar A; Kaiser, Jeffrey R; Lin, Aiping; Cotten, Charles Michael; Murray, Jeffrey; Page, Grier; Hallman, Mikko; Lifton, Richard P; Zhang, Heping

    2015-12-01

    Emerging data suggest intraventricular hemorrhage (IVH) of the preterm neonate is a complex disorder with contributions from both the environment and the genome. Environmental analyses suggest factors mediating both cerebral blood flow and angiogenesis contribute to IVH, while candidate gene studies report variants in angiogenesis, inflammation, and vascular pathways. Gene-by-environment interactions demonstrate the interaction between the environment and the genome, and a non-replicated genome-wide association study suggests that both environmental and genetic factors contribute to the risk for severe IVH in very low-birth weight preterm neonates.

  18. Peripheral retinal non-perfusion and treatment response in branch retinal vein occlusion

    PubMed Central

    Abri Aghdam, Kaveh; Reznicek, Lukas; Soltan Sanjari, Mostafa; Framme, Carsten; Bajor, Anna; Klingenstein, Annemarie; Kernt, Marcus; Seidensticker, Florian

    2016-01-01

    AIM To evaluate the association between the size of peripheral retinal non-perfusion and the number of intravitreal ranibizumab injections in patients with treatment-naive branch retinal vein occlusion (BRVO) and macular edema. METHODS A total of 53 patients with treatment-naive BRVO and macular edema were included. Each patient underwent a full ophthalmologic examination including optical coherence tomography (OCT) imaging and ultra wide-field fluorescein angiography (UWFA). Monthly intravitreal ranibizumab injections were applied according to the recommendations of the German Ophthalmological Society. Two independent, masked graders quantified the areas of peripheral retinal non-perfusion. RESULTS Intravitreal injections improved best-corrected visual acuity (BCVA) significantly from 22.23±16.33 Early Treatment of Diabetic Retinopathy Study (ETDRS) letters to 36.23±15.19 letters (P<0.001), and mean central subfield thickness significantly reduced from 387±115 µm to 321±115 µm (P=0.01). Mean number of intravitreal ranibizumab injections was 3.61±1.56. The size of retinal non-perfusion correlated significantly with the number of intravitreal ranibizumab injections (R=0.724, P<0.001). CONCLUSION Peripheral retinal non-perfusion in patients with BRVO associates significantly with intravitreal ranibizumab injections in patients with BRVO and macular edema. PMID:27366688

  19. Transition of differential histone H3 methylation in photoreceptors and other retinal cells during retinal differentiation

    PubMed Central

    Ueno, Kazuko; Iwagawa, Toshiro; Kuribayashi, Hiroshi; Baba, Yukihiro; Nakauchi, Hiromitsu; Murakami, Akira; Nagasaki, Masao; Suzuki, Yutaka; Watanabe, Sumiko

    2016-01-01

    To analyze cell lineage-specific transitions in global transcriptional and epigenetic changes during retinogenesis, we purified retinal cells from normal mice during postnatal development into two fractions, namely, photoreceptors and other retinal cells, based on Cd73 expression, and performed RNA sequencing and ChIP sequencing of H3K27me3 and H3K4me3. Genes expressed in the photoreceptor lineage were marked with H3K4me3 in the Cd73-positive cell fraction; however, the level of H3K27me3 was very low in both Cd73-positive and -negative populations. H3K27me3 may be involved in spatio-temporal onset of a subset of bipolar-related genes. Subsets of genes expressed in amacrine and retinal ganglion cells, which are early-born retinal cell types, were suggested to be maintained in a silent state by H3K27me3 during late-stage retinogenesis. In the outer nuclear layer, upregulation of Rho and rod-related genes were observed in Ezh2-ablated retina, suggesting a role for H3K27me3 in the maintenance of proper expression levels. Taken together, our data on the transition of lineage-specific molecular signatures during development suggest that histone methylation is involved in retinal differentiation and maintenance through cell lineage-specific mechanisms. PMID:27377164

  20. Adaptive optics technology for high-resolution retinal imaging.

    PubMed

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

    2012-12-27

    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.

  1. The effect of dendritic cells on the retinal cell transplantation

    SciTech Connect

    Oishi, Akio; Nagai, Takayuki; Mandai, Michiko Takahashi, Masayo; Yoshimura, Nagahisa

    2007-11-16

    The potential of bone marrow cell-derived immature dendritic cells (myeloid iDCs) in modulating the efficacy of retinal cell transplantation therapy was investigated. (1) In vitro, myeloid iDCs but not BMCs enhanced the survival and proliferation of embryonic retinal cells, and the expression of various neurotrophic factors by myeloid iDCs was confirmed with RT-PCR. (2) In subretinal transplantation, neonatal retinal cells co-transplanted with myeloid iDCs showed higher survival rate compared to those transplanted without myeloid iDCs. (3) CD8 T-cells reactive against donor retinal cells were significantly increased in the mice with transplantation of retinal cells alone. These results suggested the beneficial effects of the use of myeloid iDCs in retinal cell transplantation therapy.

  2. Contribution of Microglia-Mediated Neuroinflammation to Retinal Degenerative Diseases

    PubMed Central

    Madeira, Maria H.; Boia, Raquel; Santos, Paulo F.; Ambrósio, António F.; Santiago, Ana R.

    2015-01-01

    Retinal degenerative diseases are major causes of vision loss and blindness worldwide and are characterized by chronic and progressive neuronal loss. One common feature of retinal degenerative diseases and brain neurodegenerative diseases is chronic neuroinflammation. There is growing evidence that retinal microglia, as in the brain, become activated in the course of retinal degenerative diseases, having a pivotal role in the initiation and propagation of the neurodegenerative process. A better understanding of the events elicited and mediated by retinal microglia will contribute to the clarification of disease etiology and might open new avenues for potential therapeutic interventions. This review aims at giving an overview of the roles of microglia-mediated neuroinflammation in major retinal degenerative diseases like glaucoma, age-related macular degeneration, and diabetic retinopathy. PMID:25873768

  3. Adaptive Optics Technology for High-Resolution Retinal Imaging

    PubMed Central

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

    2013-01-01

    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 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. PMID:23271600

  4. Detection and measurement of retinal blood vessel pulsatile motion

    NASA Astrophysics Data System (ADS)

    Xiao, Di; Frost, Shaun; Vignarajan, Janardhan; An, Dong; Tay-Kearney, Mei-Ling; Kanagasingam, Yogi

    2016-03-01

    Retinal photography is a non-invasive and well-accepted clinical diagnosis of ocular diseases. Qualitative and quantitative assessment of retinal images is crucial in ocular diseases related clinical application. Pulsatile properties caused by cardiac rhythm, such as spontaneous venous pulsation (SVP) and pulsatile motion of small arterioles, can be visualized by dynamic retinal imaging techniques and provide clinical significance. In this paper, we aim at vessel pulsatile motion detection and measurement. We proposed a novel approach for pulsatile motion measurement of retinal blood vessels by applying retinal image registration, blood vessel detection and blood vessel motion detection and measurement on infrared retinal image sequences. The performance of the proposed methods was evaluated on 8 image sequences with 240 images. A preliminary result has demonstrated the good performance of the method for blood vessel pulsatile motion observation and measurement.

  5. Retinal pigment epithelial change and partial lipodystrophy.

    PubMed Central

    Davis, T. M.; Holdright, D. R.; Schulenberg, W. E.; Turner, R. C.; Joplin, G. F.

    1988-01-01

    Cuticular drusen and retinal pigment epithelial changes were found incidentally in a 27 year old Lebanese woman during assessment of partial lipodystrophy. Her vision was normal despite involvement of both maculae. The patient had hypocomplementaemia, but serum C3 nephritic factor was absent and renal function was normal. She had impaired glucose tolerance and a continuous infusion of glucose with model assessment (CIGMA) test revealed low normal tissue insulin sensitivity and high normal pancreatic beta cell function. Mild fasting hypertriglyceridaemia (2.0 mmol/l) may have been secondary to impaired insulin sensitivity. Endocrine function was otherwise normal apart from a completely absent growth hormone response to adequate hypoglycaemia. The simultaneous occurrence of partial lipodystrophy and retinal pigmentary epithelial and basement membrane changes appears to be a newly recognized syndrome. Images Figure 1 Figure 2 PMID:3255937

  6. Supervised retinal biometrics in different lighting conditions.

    PubMed

    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.

  7. Computational model of retinal photocoagulation and rupture

    NASA Astrophysics Data System (ADS)

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

    2009-02-01

    In patterned scanning laser photocoagulation, shorter duration (< 20 ms) pulses help reduce thermal damage beyond the photoreceptor layer, decrease treatment time and minimize pain. However, safe therapeutic window (defined as the ratio of rupture threshold power to that of light coagulation) decreases for shorter exposures. To quantify the extent of thermal damage in the retina, and maximize the therapeutic window, we developed a computational model of retinal photocoagulation and rupture. Model parameters were adjusted to match measured thresholds of vaporization, coagulation, and retinal pigment epithelial (RPE) damage. Computed lesion width agreed with histological measurements in a wide range of pulse durations and power. Application of ring-shaped beam profile was predicted to double the therapeutic window width for exposures in the range of 1 - 10 ms.

  8. Biophotons Contribute to Retinal Dark Noise.

    PubMed

    Li, Zehua; Dai, Jiapei

    2016-06-01

    The discovery of dark noise in retinal photoreceptors resulted in a long-lasting controversy over its origin and the underlying mechanisms. Here, we used a novel ultra-weak biophoton imaging system (UBIS) to detect biophotonic activity (emission) under dark conditions in rat and bullfrog (Rana catesbeiana) retinas in vitro. We found a significant temperature-dependent increase in biophotonic activity that was completely blocked either by removing intracellular and extracellular Ca(2+) together or inhibiting phosphodiesterase 6. These findings suggest that the photon-like component of discrete dark noise may not be caused by a direct contribution of the thermal activation of rhodopsin, but rather by an indirect thermal induction of biophotonic activity, which then activates the retinal chromophore of rhodopsin. Therefore, this study suggests a possible solution regarding the thermal activation energy barrier for discrete dark noise, which has been debated for almost half a century. PMID:27059222

  9. Retinal Light Processing Using Carbon Nanotubes

    NASA Technical Reports Server (NTRS)

    Loftus, David J. (Inventor); Leng, Theodore (Inventor); Fishman, Harvey (Inventor)

    2004-01-01

    Method and system for processing light signals received by the eye of a human or other animal, where the eye may be compromised or non-functioning. Incident light is received at first and second pixels in a photodetector array and provides a pixel electrical signal representing the received light. Each of an array of carbon nanotube (CNT) towers is connected to a pixel, has a first tower end penetrating a retinal active layer of the animal and has a second tower end positioned to receive to receive and transport the pixel electrical signal to the retinal active layer. The CNT tower may be coated with a biologically active substance or chemically modified to promote neurite connections with the tower. The photoreceptor array can be provide with a signal altering mechanism that alters at least one of light intensity and wavelength intensity sensed by a first pixel relative to a second pixel, to correct for one or more selected eye problems.

  10. Retinal Image Simulation of Subjective Refraction Techniques.

    PubMed

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

    2016-01-01

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

  11. Retinal Image Simulation of Subjective Refraction Techniques

    PubMed Central

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

    2016-01-01

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

  12. Dog Models for Blinding Inherited Retinal Dystrophies

    PubMed Central

    Komáromy, András M.

    2015-01-01

    Abstract Spontaneous canine models exist for several inherited retinal dystrophies. This review will summarize the models and indicate where they have been used in translational gene therapy trials. The RPE65 gene therapy trials to treat childhood blindness are a good example of how studies in dogs have contributed to therapy development. Outcomes in human clinical trials are compared and contrasted with the result of the preclinical dog trials. PMID:25671556

  13. Dog models for blinding inherited retinal dystrophies.

    PubMed

    Petersen-Jones, Simon M; Komáromy, András M

    2015-03-01

    Spontaneous canine models exist for several inherited retinal dystrophies. This review will summarize the models and indicate where they have been used in translational gene therapy trials. The RPE65 gene therapy trials to treat childhood blindness are a good example of how studies in dogs have contributed to therapy development. Outcomes in human clinical trials are compared and contrasted with the result of the preclinical dog trials.

  14. Dog models for blinding inherited retinal dystrophies.

    PubMed

    Petersen-Jones, Simon M; Komáromy, András M

    2015-03-01

    Spontaneous canine models exist for several inherited retinal dystrophies. This review will summarize the models and indicate where they have been used in translational gene therapy trials. The RPE65 gene therapy trials to treat childhood blindness are a good example of how studies in dogs have contributed to therapy development. Outcomes in human clinical trials are compared and contrasted with the result of the preclinical dog trials. PMID:25671556

  15. Automated retinal robotic laser system instrumentation

    NASA Astrophysics Data System (ADS)

    Barrett, Steven F.; Wright, Cameron H. G.; Jerath, Maya R.; Lewis, R. Stephen, II; Dillard, Bryan C.; Rylander, Henry G., III; Welch, Ashley J.

    1995-05-01

    Researchers at the University of Texas at Austin's Biomedical Engineering Laser Laboratory investigating the medical applications of lasers have worked toward the development of a retinal robotic laser system. The ultimate goal of this ongoing project is to precisely place and control the depth of laser lesions for the treatment of various retinal diseases such as diabetic retinopathy and retinal tears. Researchers at the USAF Academy's Department of Electrical Engineering have also become involved with this research due to similar interests. Separate low speed prototype subsystems have been developed to control lesion depth using lesion reflectance feedback parameters and lesion placement using retinal vessels as tracking landmarks. Both subsystems have been successfully demonstrated in vivo on pigmented rabbits using an argon continuous wave laser. Work is ongoing to build a prototype system to simultaneously control lesion depth and placement. The instrumentation aspects of the prototype subsystems were presented at SPIE Conference 1877 in January 1993. Since then our efforts have concentrated on combining the lesion depth control subsystem and the lesion placement subsystem into a single prototype capable of simultaneously controlling both parameters. We have designed this combined system CALOSOS for Computer Aided Laser Optics System for Ophthalmic Surgery. An initial CALOSOS prototype design is provided. We have also investigated methods to improve system response time. The use of high speed non-standard frame rate CCD cameras and high speed local bus frame grabbers hosted on personal computers are being investigated. A review of system testing in vivo to date is provided in SPIE Conference proceedings 2374-49 (Novel Applications of Lasers and Pulsed Power, Dual-Use Applications of Lasers: Medical session).

  16. Interconnection between brain and retinal neurodegenerations.

    PubMed

    Jindal, Vishal

    2015-01-01

    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 Aβ-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.

  17. Retinal prosthetics, optogenetics, and chemical photoswitches.

    PubMed

    Marc, Robert; Pfeiffer, Rebecca; Jones, Bryan

    2014-10-15

    Three technologies have emerged as therapies to restore light sensing to profoundly blind patients suffering from late-stage retinal degenerations: (1) retinal prosthetics, (2) optogenetics, and (3) chemical photoswitches. Prosthetics are the most mature and the only approach in clinical practice. Prosthetic implants require complex surgical intervention and provide only limited visual resolution but can potentially restore navigational ability to many blind patients. Optogenetics uses viral delivery of type 1 opsin genes from prokaryotes or eukaryote algae to restore light responses in survivor neurons. Targeting and expression remain major problems, but are potentially soluble. Importantly, optogenetics could provide the ultimate in high-resolution vision due to the long persistence of gene expression achieved in animal models. Nevertheless, optogenetics remains challenging to implement in human eyes with large volumes, complex disease progression, and physical barriers to viral penetration. Now, a new generation of photochromic ligands or chemical photoswitches (azobenzene-quaternary ammonium derivatives) can be injected into a degenerated mouse eye and, in minutes to hours, activate light responses in neurons. These photoswitches offer the potential for rapidly and reversibly screening the vision restoration expected in an individual patient. Chemical photoswitch variants that persist in the cell membrane could make them a simple therapy of choice, with resolution and sensitivity equivalent to optogenetics approaches. A major complexity in treating retinal degenerations is retinal remodeling: pathologic network rewiring, molecular reprogramming, and cell death that compromise signaling in the surviving retina. Remodeling forces a choice between upstream and downstream targeting, each engaging different benefits and defects. Prosthetics and optogenetics can be implemented in either mode, but the use of chemical photoswitches is currently limited to downstream

  18. Interconnection between brain and retinal neurodegenerations.

    PubMed

    Jindal, Vishal

    2015-01-01

    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 Aβ-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

  19. Retinal Detachment due to CrossFit Training Injury.

    PubMed

    Joondeph, Stephanie A; Joondeph, Brian C

    2013-01-01

    The purpose of this paper is to describe a traumatic retinal detachment occurring as a result of CrossFit training using an elastic exercise band. The patient sustained an ocular injury from an elastic band during CrossFit training, resulting in a giant retinal dialysis and retinal detachment, which were successfully repaired. Trainers and athletes need to be aware of the potential for ocular injury from elastic exercise bands and take appropriate precautions.

  20. Retinal Detachment due to CrossFit Training Injury

    PubMed Central

    Joondeph, Stephanie A.; Joondeph, Brian C.

    2013-01-01

    The purpose of this paper is to describe a traumatic retinal detachment occurring as a result of CrossFit training using an elastic exercise band. The patient sustained an ocular injury from an elastic band during CrossFit training, resulting in a giant retinal dialysis and retinal detachment, which were successfully repaired. Trainers and athletes need to be aware of the potential for ocular injury from elastic exercise bands and take appropriate precautions. PMID:24106626

  1. An unusual central retinal dystrophy associated with ichthyosis vulgaris.

    PubMed

    Saatci, O A; Ozbek, Z; Köse, S; Durak, I; Kavukçu, S

    2000-06-01

    A number of ichthyosis syndromes may have retinal abnormalities such as the retinitis pigmentosa-like diffuse rod-cone dystrophy in Refsum's syndrome and the maculopathy in Sjögren-Larsson syndrome. We present two sisters who have an unusual, almost identical, bilaterally symmetric central retinal dystrophy associated with ichthyosis vulgaris in the absence of other systemic disorders. We believe that this dystrophy has not been previously described in patients with any of the known varieties of ichthyosis.

  2. Progressive Outer Retinal Necrosis and Immunosuppressive Therapy in Myasthenia Gravis

    PubMed Central

    Coisy, Solène; Ebran, Jean-Marc; Milea, Dan

    2014-01-01

    Introduction Progressive outer retinal necrosis (PORN) is a rare but devastating infectious retinitis associated with varicella zoster virus (VZV) and responsible for severe visual loss. Case Report A 59-year-old man treated for generalized myasthenia with oral azathioprine and prednisone presented with severe unilateral necrotizing retinitis. Polymerase chain reaction of the aqueous and vitreous humors was diagnostic for VZV PORN. Conclusion VZV PORN is a severe potential ocular complication of immunosuppression, prompting urgent diagnosis and appropriate treatment. PMID:24926266

  3. Retinal Detachment due to CrossFit Training Injury.

    PubMed

    Joondeph, Stephanie A; Joondeph, Brian C

    2013-01-01

    The purpose of this paper is to describe a traumatic retinal detachment occurring as a result of CrossFit training using an elastic exercise band. The patient sustained an ocular injury from an elastic band during CrossFit training, resulting in a giant retinal dialysis and retinal detachment, which were successfully repaired. Trainers and athletes need to be aware of the potential for ocular injury from elastic exercise bands and take appropriate precautions. PMID:24106626

  4. Reversibility of retinal microvascular changes in severe falciparum malaria.

    PubMed

    Maude, Richard J; Kingston, Hugh W F; Joshi, Sonia; Mohanty, Sanjib; Mishra, Saroj K; White, Nicholas J; Dondorp, Arjen M

    2014-09-01

    Malarial retinopathy allows detailed study of central nervous system vascular pathology in living patients with severe malaria. An adult with cerebral malaria is described who had prominent retinal whitening with corresponding retinal microvascular obstruction, vessel dilatation, increased vascular tortuosity, and blood retinal barrier leakage with decreased visual acuity, all of which resolved on recovery. Additional study of these features and their potential role in elucidating the pathogenesis of cerebral malaria is warranted.

  5. Three cases of suprachoroidal hemorrhage associated with chest compression or asphyxiation and detected using postmortem computed tomography.

    PubMed

    Oshima, Toru; Yoshikawa, Hiroshi; Ohtani, Maki; Mimasaka, Sohtaro

    2015-05-01

    We report 3 cases of suprachoroidal hemorrhage (SCH) found to be triggered by increased intrathoracic pressure and detected using postmortem computed tomography (PMCT). Case 1 was a man aged in his 50s who was found dead at a landslide site. The autopsy showed clogging of the upper respiratory tract with soil debris from the landslide. The cause of death was determined to be asphyxia. PMCT showed SCH in both eyes, which was believed to be caused by chest compression or choking on the soil debris from the landslide. Case 2 was a woman aged in her 60s who was found dead in the sea. The autopsy revealed injuries primarily to her chest. We concluded that the cause of death was drowning. PMCT showed SCH in her right eye that was believed to be caused by chest compression. Case 3 was a woman aged in her 80s who was buried in a snowdrift and potentially died from hypothermia. PMCT showed SCH in both eyes, which was considered to be from an increase in intrathoracic pressure that might have been caused by the burial in the snow. Histological findings showed serous retinal detachment associated with retinal pigment epithelium damage due to SCH, which indicated that she was alive for several hours after the onset of SCH. The increase in intrathoracic pressure caused by dyspnea or chest compression was considered responsible for the onset of SCH in all of the present cases. PMCT might assist with the differential diagnosis of traumatic asphyxiation by SCH. PMID:25533924

  6. Central serous choroidopathy with bullous retinal detachment.

    PubMed

    Tsukahara, I; Uyama, M

    1978-05-16

    We report here a new type of secondary retinal detachment that has never been clearly defined. The characteristic features of the disease are: (1) prevalence in middle-aged males, (2) bilateral involvement, (3) frequent existence of prodromal lesions that over long periods resemble central serous retinopathy, (4) in the evolution stage, appearance of multiple yellowish white exudative flecks of one-half to one disc in diameter at or near the posterior pole of the fundus, (5) fluorescein studies revealing pronounced leakage of dye from the choroid into the subretinal space at the sites of exudates, (6) retinal detachment of various degrees with shifting subretinal fluid and without tears, (7) no evidence of intraocular inflammation, (8) no filling abnormalities seen in the choroidal fluorescence, (9) no response to medical therapy, including steroids and antibiotics, (10) photocoagulation to leakage sites leading to rapid resolution of retinal detachment; otherwise, spontaneous healing of detachment occurring within about 7-9 months, leaving fibroblastic macular scars and marked visual loss, and (11) no evidence of systemic findings that may be of etiologic significance. From this characteristic clinical picture, the idea of a new clinical entity must be considered. Our findings in 35 eyes from 18 Japanese patients are discussed.

  7. Enhancing retinal images by nonlinear registration

    NASA Astrophysics Data System (ADS)

    Molodij, G.; Ribak, E. N.; Glanc, M.; Chenegros, G.

    2015-05-01

    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 in the perspective to perform a medical diagnosis. The main purpose would be to assist health care practitioners by enhancing the spatial resolution of the retinal images and increase the level of confidence of the abnormal feature detection. 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 of high interest in a medical diagnosis.

  8. Adaptive optics retinal imaging: emerging clinical applications.

    PubMed

    Godara, Pooja; Dubis, Adam M; Roorda, Austin; Duncan, Jacque L; Carroll, Joseph

    2010-12-01

    The human retina is a uniquely accessible tissue. Tools like scanning laser ophthalmoscopy and spectral domain-optical coherence tomography provide clinicians with remarkably clear pictures of the living retina. Although the anterior optics of the eye permit such non-invasive visualization of the retina and associated pathology, the same optics induce significant aberrations that obviate cellular-resolution imaging in most cases. Adaptive optics (AO) imaging systems use active optical elements to compensate for aberrations in the optical path between the object and the camera. When applied to the human eye, AO allows direct visualization of individual rod and cone photoreceptor cells, retinal pigment epithelium cells, and white blood cells. AO imaging has changed the way vision scientists and ophthalmologists see the retina, helping to clarify our understanding of retinal structure, function, and the etiology of various retinal pathologies. Here, we review some of the advances that were made possible with AO imaging of the human retina and discuss applications and future prospects for clinical imaging.

  9. Halting progressive neurodegeneration in advanced retinitis pigmentosa

    PubMed Central

    Koch, Susanne F.; Tsai, Yi-Ting; Duong, Jimmy K.; Wu, Wen-Hsuan; Hsu, Chun-Wei; Wu, Wei-Pu; Bonet-Ponce, Luis; Lin, Chyuan-Sheng; Tsang, Stephen H.

    2015-01-01

    Hereditary retinal degenerative diseases, such as retinitis pigmentosa (RP), are characterized by the progressive loss of rod photoreceptors followed by loss of cones. While retinal gene therapy clinical trials demonstrated temporary improvement in visual function, this approach has yet to achieve sustained functional and anatomical rescue after disease onset in patients. The lack of sustained benefit could be due to insufficient transduction efficiency of viral vectors (“too little”) and/or because the disease is too advanced (“too late”) at the time therapy is initiated. Here, we tested the latter hypothesis and developed a mouse RP model that permits restoration of the mutant gene in all diseased photoreceptor cells, thereby ensuring sufficient transduction efficiency. We then treated mice at early, mid, or late disease stages. At all 3 time points, degeneration was halted and function was rescued for at least 1 year. Not only do our results demonstrate that gene therapy effectively preserves function after the onset of degeneration, our study also demonstrates that there is a broad therapeutic time window. Moreover, these results suggest that RP patients are treatable, despite most being diagnosed after substantial photoreceptor loss, and that gene therapy research must focus on improving transduction efficiency to maximize clinical impact. PMID:26301813

  10. Neural differentiation and synaptogenesis in retinal development

    PubMed Central

    Fan, Wen-juan; Li, Xue; Yao, Huan-ling; Deng, Jie-xin; Liu, Hong-liang; Cui, Zhan-jun; Wang, Qiang; Wu, Ping; Deng, Jin-bo

    2016-01-01

    To investigate the pattern of neural differentiation and synaptogenesis in the mouse retina, immunolabeling, BrdU assay and transmission electron microscopy were used. We show that the neuroblastic cell layer is the germinal zone for neural differentiation and retinal lamination. Ganglion cells differentiated initially at embryonic day 13 (E13), and at E18 horizontal cells appeared in the neuroblastic cell layer. Neural stem cells in the outer neuroblastic cell layer differentiated into photoreceptor cells as early as postnatal day 0 (P0), and neural stem cells in the inner neuroblastic cell layer differentiated into bipolar cells at P7. Synapses in the retina were mainly located in the outer and inner plexiform layers. At P7, synaptophysin immunostaining appeared in presynaptic terminals in the outer and inner plexiform layers with button-like structures. After P14, presynaptic buttons were concentrated in outer and inner plexiform layers with strong staining. These data indicate that neural differentiation and synaptogenesis in the retina play important roles in the formation of retinal neural circuitry. Our study showed that the period before P14, especially between P0 and P14, represents a critical period during retinal development. Mouse eye opening occurs during that period, suggesting that cell differentiation and synaptic formation lead to the attainment of visual function. PMID:27073386

  11. Finite element modeling of retinal prosthesis mechanics

    NASA Astrophysics Data System (ADS)

    Basinger, B. C.; Rowley, A. P.; Chen, K.; Humayun, M. S.; Weiland, J. D.

    2009-10-01

    Epiretinal prostheses used to treat degenerative retina diseases apply stimulus via an electrode array fixed to the ganglion cell side of the retina. Mechanical pressure applied by these arrays to the retina, both during initial insertion and throughout chronic use, could cause sufficient retinal damage to reduce the device's effectiveness. In order to understand and minimize potential mechanical damage, we have used finite element analysis to model mechanical interactions between an electrode array and the retina in both acute and chronic loading configurations. Modeling indicates that an acute tacking force distributes stress primarily underneath the tack site and heel edge of the array, while more moderate chronic stresses are distributed more evenly underneath the array. Retinal damage in a canine model chronically implanted with a similar array occurred in correlating locations, and model predictions correlate well with benchtop eyewall compression tests. This model provides retinal prosthesis researchers with a tool to optimize the mechanical electrode array design, but the techniques used here represent a unique effort to combine a modifiable device and soft biological tissues in the same model and those techniques could be extended to other devices that come into mechanical contact with soft neural tissues.

  12. Antisense Oligonucleotide Therapy for Inherited Retinal Dystrophies.

    PubMed

    Gerard, Xavier; Garanto, Alejandro; Rozet, Jean-Michel; Collin, Rob W J

    2016-01-01

    Inherited retinal dystrophies (IRDs) are an extremely heterogeneous group of genetic diseases for which currently no effective treatment strategies exist. Over the last decade, significant progress has been made utilizing gene augmentation therapy for a few genetic subtypes of IRD, although several technical challenges so far prevent a broad clinical application of this approach for other forms of IRD. Many of the mutations leading to these retinal diseases affect pre-mRNA splicing of the mutated genes . Antisense oligonucleotide (AON)-mediated splice modulation appears to be a powerful approach to correct the consequences of such mutations at the pre-mRNA level , as demonstrated by promising results in clinical trials for several inherited disorders like Duchenne muscular dystrophy, hypercholesterolemia and various types of cancer. In this mini-review, we summarize ongoing pre-clinical research on AON-based therapy for a few genetic subtypes of IRD , speculate on other potential therapeutic targets, and discuss the opportunities and challenges that lie ahead to translate splice modulation therapy for retinal disorders to the clinic.

  13. [Optogenetics and prosthetic treatment of retinal degeneration].

    PubMed

    Kirpichnikov, M P; Ostrovskiy, M A

    2015-01-01

    This is a review of the current state of optogenetics-based research in the field of ophthalmology and physiology of vision. Optogenetics employs an interdisciplinary approach that amalgamates gene engineering, optics, and physiology. It involves exogenous expression of a light-activated protein in a very particular retinal cell enabling regulation (stimulation vs. inhibition) of its physiological activity. The experience with gene therapy came in very useful for optogenetics. However, unlike gene therapy, which is aimed at repairing damaged genes or replacing them with healthy ones, optogenetics is focused on protein genes delivery for further molecular control of the cell. In retina, the loss of photoreceptors is not necessarily followed by neuronal loss (at least ganglion cells remain intact), which determines the practicability of prosthetic treatment. Clinical trials can now be considered, owing to the first successful conversion of ganglion cells of mouse degenerative retinas into artificial photoreceptive cells with ON and OFF receptive fields, which is crucial for spatial vision. The following issues are reviewed here in detail: 1. Choice of cell targets within the degenerative retina. 2. Strategy of utilizing the existing light-sensitive agents and development of new optogenetic tools. 3. Gene delivery and expression in retinal cells. 4. Methods of evaluating the treatment success. 5. Selection criteria for optogenetic prosthetics. The conclusion discusses currently unsolved problems and prospects for optogenetic approaches to retinal prosthetics.

  14. Optimal retinal cyst segmentation from OCT images

    NASA Astrophysics Data System (ADS)

    Oguz, Ipek; Zhang, Li; Abramoff, Michael D.; Sonka, Milan

    2016-03-01

    Accurate and reproducible segmentation of cysts and fluid-filled regions from retinal OCT images is an important step allowing quantification of the disease status, longitudinal disease progression, and response to therapy in wet-pathology retinal diseases. However, segmentation of fluid-filled regions from OCT images is a challenging task due to their inhomogeneous appearance, the unpredictability of their number, size and location, as well as the intensity profile similarity between such regions and certain healthy tissue types. While machine learning techniques can be beneficial for this task, they require large training datasets and are often over-fitted to the appearance models of specific scanner vendors. We propose a knowledge-based approach that leverages a carefully designed cost function and graph-based segmentation techniques to provide a vendor-independent solution to this problem. We illustrate the results of this approach on two publicly available datasets with a variety of scanner vendors and retinal disease status. Compared to a previous machine-learning based approach, the volume similarity error was dramatically reduced from 81:3+/-56:4% to 22:2+/-21:3% (paired t-test, p << 0:001).

  15. Alveolar hemorrhage in vasculitis: primary and secondary.

    PubMed

    Cordier, Jean-François; Cottin, Vincent

    2011-06-01

    Diffuse alveolar hemorrhage (DAH) in primary and secondary vasculitis occurs when capillaritis is present. The diagnosis of DAH is considered in patients who develop progressive dyspnea with alveolar opacities on chest imaging (with density ranging from ground glass to consolidation) that cannot be explained otherwise. Hemoptysis, a valuable sign, is often absent. A decline of blood hemoglobin level over a few days without hemolysis or any hemorrhage elsewhere should be an alert for DAH. Bronchoalveolar lavage, retrieving bright red fluid, is the best diagnostic clue. Lung biopsy is not recommended. A search for anti-neutrophil cytoplasmic autoantibodies (ANCAs) is mandatory. Once DAH is diagnosed and hemodynamic as well as infectious causes have been excluded, ANCA-associated vasculitis is taken into account (mainly microscopic polyangiitis or Wegener granulomatosis, and, exceptionally, Churg-Strauss syndrome). Drug-induced DAH, especially antithyroid drugs such as propylthiouracil may be coupled with ANCA. Isolated DAH with capillaritis with or without ANCA is rare. DAH in systemic lupus erythematosus is either associated or not with capillaritis. Treatment of DAH should target the underlying disorder. In the primary vasculitides, corticosteroids and immunosuppressants, especially cyclophosphamide, are the mainstay of therapy, but plasma exchange, particularly in severe DAH, is the rule, although evidence of its effectiveness is awaited.

  16. Hypercoagulability in hereditary hemorrhagic telangiectasia with epilepsy.

    PubMed

    Finsterer, Josef; Sehnal, Ernst

    2015-01-01

    Recent data indicate that in patients with hereditary hemorrhagic teleangiectasia (HHT), low iron levels due to inadequate replacement after hemorrhagic iron losses are associated with elevated factor-VIII plasma levels and consecutively increased risk of venous thrombo-embolism. Here, we report a patient with HHT, low iron levels, elevated factor-VIII, and recurrent venous thrombo-embolism. A 64-year-old multimorbid Serbian gipsy was diagnosed with HHT at age 62 years. He had a history of recurrent epistaxis, teleangiectasias on the lips, renal and pulmonary arterio-venous malformations, and a family history positive for HHT. He had experienced recurrent venous thrombosis (mesenteric vein thrombosis, portal venous thrombosis, deep venous thrombosis), insufficiently treated with phenprocoumon during 16 months and gastro-intestinal bleeding. Blood tests revealed sideropenia and elevated plasma levels of coagulation factor-VIII. His history was positive for diabetes, arterial hypertension, hyperlipidemia, smoking, cerebral abscess, recurrent ischemic stroke, recurrent ileus, peripheral arterial occluding disease, polyneuropathy, mild renal insufficiency, and epilepsy. Following recent findings, hypercoagulability was attributed to the sideropenia-induced elevation of coagulation factor-VIII. In conclusion, HHT may be associated with hypercoagulability due to elevated factor-VIII associated with low serum iron levels from recurrent bleeding. Iron substitution may prevent HHT patients from hypercoagulability. PMID:26167029

  17. Massive suprachoroidal hemorrhage: Surgical management and outcome

    PubMed Central

    Laube, Thomas; Brockmann, Claudia; Bornfeld, Norbert

    2015-01-01

    Objective: To describe options for vitreoretinal surgery in the management of massive suprachoroidal hemorrhage (SCH). Methods: Visual acuity (VA), ocular findings, timing of surgical intervention, surgical procedures, and outcomes of four patients diagnosed with massive SCH and admitted to the University Eye Clinic Essen were reviewed retrospectively. Results: Four eyes of four patients (mean age, 82 years; range, 74–89 years) were studied. In three cases the occurrence of SCH was related to cataract surgery and occurred intra- or postoperatively. One patient developed spontaneous SCH of unclear origin. Three patients had a history of arterial hypertension; one eye had high myopia, two patients suffered from cardiovascular diseases, and two patients had glaucoma. Postoperative follow up of the patients ranged from 5 to 29.5 months (mean, 19.6 months). Transscleral drainage of SCH was in all cases combined with pars plana vitrectomy, use of heavy liquids (perfluorodecalin) and silicone oil tamponade. The mean time interval from hemorrhage to surgical intervention was 16.5 days (range 5–29 days). Preoperative VA of all eyes was light perception. Two patients achieved a final postoperative visual acuity of 20/20 and 20/320, respectively, one patient improved to hand motion, and one patient resulted in no light perception. Conclusions: Surgical interventions including transscleral drainage of SCH, vitrectomy, and silicone oil tamponade are valuable options in the management of massive SCH to save the eye and possibly improve the otherwise extreme poor prognosis.

  18. Subarachnoid hemorrhage due to retained lumbar drain.

    PubMed

    Guppy, Kern H; Silverthorn, James W; Akins, Paul T

    2011-12-01

    Intrathecal spinal catheters (lumbar drains) are indicated for several medical and surgical conditions. In neurosurgical procedures, they are used to reduce intracranial and intrathecal pressures by diverting CSF. They have also been placed for therapeutic access to administer drugs, and more recently, vascular surgeons have used them to improve spinal cord perfusion during the treatment of thoracic aortic aneurysms. Insertion of these lumbar drains is not without attendant complications. One complication is the shearing of the distal end of the catheter with a resultant retained fragment. The authors report the case of a 65-year-old man who presented with a subarachnoid hemorrhage due to the migration of a retained lumbar drain that sheared off during its removal. To the best of the authors' knowledge, this is the first case of rostral migration of a retained intrathecal catheter causing subarachnoid hemorrhage. The authors review the literature on retained intrathecal spinal catheters, and their findings support either early removal of easily accessible catheters or close monitoring with serial imaging.

  19. Blocking neutrophil diapedesis prevents hemorrhage during thrombocytopenia

    PubMed Central

    Hillgruber, Carina; Pöppelmann, Birgit; Weishaupt, Carsten; Steingräber, Annika Kathrin; Wessel, Florian; Berdel, Wolfgang E.; Gessner, J. Engelbert; Ho-Tin-Noé, Benoît

    2015-01-01

    Spontaneous organ hemorrhage is the major complication in thrombocytopenia with a potential fatal outcome. However, the exact mechanisms regulating vascular integrity are still unknown. Here, we demonstrate that neutrophils recruited to inflammatory sites are the cellular culprits inducing thrombocytopenic tissue hemorrhage. Exposure of thrombocytopenic mice to UVB light provokes cutaneous petechial bleeding. This phenomenon is also observed in immune-thrombocytopenic patients when tested for UVB tolerance. Mechanistically, we show, analyzing several inflammatory models, that it is neutrophil diapedesis through the endothelial barrier that is responsible for the bleeding defect. First, bleeding is triggered by neutrophil-mediated mechanisms, which act downstream of capturing, adhesion, and crawling on the blood vessel wall and require Gαi signaling in neutrophils. Second, mutating Y731 in the cytoplasmic tail of VE-cadherin, known to selectively affect leukocyte diapedesis, but not the induction of vascular permeability, attenuates bleeding. Third, and in line with this, simply destabilizing endothelial junctions by histamine did not trigger bleeding. We conclude that specifically targeting neutrophil diapedesis through the endothelial barrier may represent a new therapeutic avenue to prevent fatal bleeding in immune-thrombocytopenic patients. PMID:26169941

  20. Diffuse Alveolar Hemorrhage in Acute Myeloid Leukemia.

    PubMed

    Nanjappa, Sowmya; Jeong, Daniel K; Muddaraju, Manjunath; Jeong, Katherine; Hill, Ebone D; Greene, John N

    2016-07-01

    Diffuse alveolar hemorrhage is a potentially fatal pulmonary disease syndrome that affects individuals with hematological and nonhematological malignancies. The range of inciting factors is wide for this syndrome and includes thrombocytopenia, underlying infection, coagulopathy, and the frequent use of anticoagulants, given the high incidence of venous thrombosis in this population. Dyspnea, fever, and cough are commonly presenting symptoms. However, clinical manifestations can be variable. Obvious bleeding (hemoptysis) is not always present and can pose a potential diagnostic challenge. Without prompt treatment, hypoxia that rapidly progresses to respiratory failure can occur. Diagnosis is primarily based on radiological and bronchoscopic findings. This syndrome is especially common in patients with hematological malignancies, given an even greater propensity for thrombocytopenia as a result of bone marrow suppression as well as the often prolonged immunosuppression in this patient population. The syndrome also has an increased incidence in individuals with hematological malignancies who have received a bone marrow transplant. We present a case series of 5 patients with acute myeloid leukemia presenting with diffuse alveolar hemorrhage at our institution. A comparison of clinical manifestations, radiographic findings, treatment course, and outcomes are described. A review of the literature and general overview of the diagnostic evaluation, differential diagnoses, pathophysiology, and treatment of this syndrome are discussed. PMID:27556667