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Sample records for anterior visual pathway

  1. Orbital and anterior visual pathway infection and inflammation

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    Wyngaert, Roel de; Demaerel, Philippe [University Hospitals K.U. Leuven, Department of Radiology, Leuven (Belgium); Casteels, Ingele [University Hospitals K.U. Leuven, Department of Ophthalmology, Leuven (Belgium)

    2009-06-15

    Orbital and anterior visual pathway infection and inflammation represent approximately 10-15% of all orbital pathology. Both conditions can occur separately but occasionally they can be observed simultaneously. While the diagnosis of infection is usually straightforward, it is important to depict the lesions and to know the potential devastating complications. CT plays an important role in confirming the clinical suspicion of orbital infection. The diagnosis and differential diagnosis of inflammation is more challenging. Differentiating inflammation from lymphoproliferative diseases and tumours can be difficult. MR imaging plays an important role but a dedicated orbital imaging protocol is mandatory. (orig.)

  2. Functional magnetic resonance imaging evaluation of visual cortex activation in patients with anterior visual pathway lesions

    Institute of Scientific and Technical Information of China (English)

    Xiufeng Song; Guohua Wang; Tong Zhang; Lei Feng; Peng An; Yueli Zhu

    2012-01-01

    The aim of this study was to examine the secondary visual cortex functional disorder in patients with glaucoma and large pituitary adenoma by functional magnetic resonance imaging, and to determine the correlation between visual field defect and primary visual cortex activation. Results showed that single eye stimulation resulted in bilateral visual cortex activation in patients with glaucoma or large pituitary adenoma. Compared with the normal control group, the extent and intensity of visual cortex activation was decreased after left and right eye stimulation, and functional magnetic resonance imaging revealed a correlation between visual field defects and visual cortex activation in patients with glaucoma and large pituitary adenoma. These functional magnetic resonance imaging data suggest that anterior optic pathway lesions can cause secondary functional disorder of the visual cortex, and that visual defects are correlated with visual cortex activation.

  3. Visual Outcome in Meningiomas Around Anterior Visual Pathways Treated With Linear Accelerator Fractionated Stereotactic Radiotherapy

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    Stiebel-Kalish, Hadas, E-mail: kalishhadas@gmail.com [Neuro-Ophthalmology Unit, Rabin Medical Center, Petah Tikva (Israel); Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Reich, Ehud [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Department of Ophthalmology, Rabin Medical Center, Petah Tikva (Israel); Gal, Lior [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Rappaport, Zvi Harry [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Department of Neurosurgery, Rabin Medical Center, Petah Tikva (Israel); Nissim, Ouzi [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Department of Neurosurgery, Sheba Medical Center, Ramat Gan (Israel); Pfeffer, Raphael [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Spiegelmann, Roberto [Sackler School of Medicine, Tel Aviv University, Tel Aviv (Israel); Stereotactic Radiosurgery Unit, Sheba Medical Center, Ramat Gan (Israel); Department of Neurosurgery, Sheba Medical Center, Ramat Gan (Israel)

    2012-02-01

    Purpose: Meningiomas threatening the anterior visual pathways (AVPs) and not amenable for surgery are currently treated with multisession stereotactic radiotherapy. Stereotactic radiotherapy is available with a number of devices. The most ubiquitous include the gamma knife, CyberKnife, tomotherapy, and isocentric linear accelerator systems. The purpose of our study was to describe a case series of AVP meningiomas treated with linear accelerator fractionated stereotactic radiotherapy (FSRT) using the multiple, noncoplanar, dynamic conformal rotation paradigm and to compare the success and complication rates with those reported for other techniques. Patients and Methods: We included all patients with AVP meningiomas followed up at our neuro-ophthalmology unit for a minimum of 12 months after FSRT. We compared the details of the neuro-ophthalmologic examinations and tumor size before and after FSRT and at the end of follow-up. Results: Of 87 patients with AVP meningiomas, 17 had been referred for FSRT. Of the 17 patients, 16 completed >12 months of follow-up (mean 39). Of the 16 patients, 11 had undergone surgery before FSRT and 5 had undergone FSRT as first-line management. Tumor control was achieved in 14 of the 16 patients, with three meningiomas shrinking in size after RT. Two meningiomas progressed, one in an area that was outside the radiation field. The visual function had improved in 6 or stabilized in 8 of the 16 patients (88%) and worsened in 2 (12%). Conclusions: Linear accelerator fractionated RT using the multiple noncoplanar dynamic rotation conformal paradigm can be offered to patients with meningiomas that threaten the anterior visual pathways as an adjunct to surgery or as first-line treatment, with results comparable to those reported for other stereotactic RT techniques.

  4. Deep Learning Guided Partitioned Shape Model for Anterior Visual Pathway Segmentation.

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    Mansoor, Awais; Cerrolaza, Juan J; Idrees, Rabia; Biggs, Elijah; Alsharid, Mohammad A; Avery, Robert A; Linguraru, Marius George

    2016-08-01

    Analysis of cranial nerve systems, such as the anterior visual pathway (AVP), from MRI sequences is challenging due to their thin long architecture, structural variations along the path, and low contrast with adjacent anatomic structures. Segmentation of a pathologic AVP (e.g., with low-grade gliomas) poses additional challenges. In this work, we propose a fully automated partitioned shape model segmentation mechanism for AVP steered by multiple MRI sequences and deep learning features. Employing deep learning feature representation, this framework presents a joint partitioned statistical shape model able to deal with healthy and pathological AVP. The deep learning assistance is particularly useful in the poor contrast regions, such as optic tracts and pathological areas. Our main contributions are: 1) a fast and robust shape localization method using conditional space deep learning, 2) a volumetric multiscale curvelet transform-based intensity normalization method for robust statistical model, and 3) optimally partitioned statistical shape and appearance models based on regional shape variations for greater local flexibility. Our method was evaluated on MRI sequences obtained from 165 pediatric subjects. A mean Dice similarity coefficient of 0.779 was obtained for the segmentation of the entire AVP (optic nerve only =0.791 ) using the leave-one-out validation. Results demonstrated that the proposed localized shape and sparse appearance-based learning approach significantly outperforms current state-of-the-art segmentation approaches and is as robust as the manual segmentation.

  5. Combined brain and anterior visual pathways' MRIs assist in early identification of neuromyelitis optica spectrum disorder at onset of optic neuritis.

    Science.gov (United States)

    Buch, D; Savatovsky, J; Gout, O; Vignal, C; Deschamps, R

    2017-03-01

    Acute optic neuritis (ON) is the initial presentation in half of neuromyelitis optica spectrum disorder (NMO-SD) cases. Our objective was to evaluate accuracy of combined MRIs of the anterior visual pathways and of the brain to correctly identify NMO-SD among patients with acute ON. We performed a retrospective study on patients with acute ON in NMO-SD (16 episodes) and first-event non-NMO-SD (32 episodes). All MRIs included exams of the brain and anterior visual pathways using T2-weighted and post-gadolinium T1-weighted coronal thin slices. Images were reviewed by a neuroradiologist who was blinded to the final diagnosis. There were no multiple sclerosis (MS)-like lesions with dissemination in space (DIS) with NMO-SD (0 vs. 53%, p < 0.01). Non-NMO-SD ON usually spared the chiasma (3 vs. 44%, p < 0.01) and the optic tracts (0 vs. 19%, p < 0.01). Optic nerve lesions were longer [median (range) 26 mm (14-64) vs. 13 mm [8-36], p < 0.01] and the number of segments involved higher (3 [1-8] vs. 1 [1-4], p < 0.01) in NMO-SD. Bilateral optic nerve involvement, or involvement of ≥3 segments, or involvement of the chiasma, or optic tracts in the absence of MS-like lesions with DIS were suggestive of NMO-SD with a sensitivity of 69% (CI 95% 41-89) and a specificity of 97% (CI 95% 84-99) (p < 0.01). Combining brain and anterior visual pathways' MRIs seems efficient for detecting acute ON patients who are at high risk for NMO-SD.

  6. Altered anterior visual system development following early monocular enucleation

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    Krista R. Kelly

    2014-01-01

    Conclusions: The novel finding of an asymmetry in morphology of the anterior visual system following long-term survival from early monocular enucleation indicates altered postnatal visual development. Possible mechanisms behind this altered development include recruitment of deafferented cells by crossing nasal fibres and/or geniculate cell retention via feedback from primary visual cortex. These data highlight the importance of balanced binocular input during postnatal maturation for typical anterior visual system morphology.

  7. Quantifying visual pathway axonal and myelin loss in multiple sclerosis and neuromyelitis optica

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    Praveena Manogaran

    2016-01-01

    Conclusions: The relationship between reductions in OCT measures of neuro-axonal health in the anterior visual pathway and MRI-based measures of myelin health in the posterior visual pathway suggests that these measures may be linked through bidirectional axonal degeneration.

  8. Interhemispheric Connections between the Primary Visual Cortical Areas via the Anterior Commissure in Human Callosal Agenesis.

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    van Meer, Nathalie; Houtman, Anne C; Van Schuerbeek, Peter; Vanderhasselt, Tim; Milleret, Chantal; Ten Tusscher, Marcel P

    2016-01-01

    Aim: In humans, images in the median plane of the head either fall on both nasal hemi-retinas or on both temporal hemi-retinas. Interhemispheric connections allow cortical cells to have receptive fields on opposite sides. The major interhemispheric connection, the corpus callosum, is implicated in central stereopsis and disparity detection in front of the fixation plane. Yet individuals with agenesis of the corpus callosum may show normal stereopsis and disparity vergence. We set out to study a possible interhemispheric connection between primary visual cortical areas via the anterior commissure to explain this inconsistency because of the major role of these cortical areas in elaborating 3D visual perception. Methods: MRI, DTI and tractography of the brain of a 53-year old man with complete callosal agenesis and normal binocular single vision was undertaken. Tractography seed points were placed in both the right and the left V1 and V2. Nine individuals with both an intact corpus callosum and normal binocularity served as controls. Results: Interhemispheric tracts through the anterior commissure linking both V1 and V2 visual cortical areas bilaterally were indeed shown in the subject with callosal agenesis. All other individuals showed interhemispheric visual connections through the corpus callosum only. Conclusion: Callosal agenesis may result in anomalous interhemispheric connections of the primary visual areas via the anterior commissure. It is proposed here that these connections form as alternative to the normal callosal pathway and may participate in binocularity.

  9. Neural pathways for visual speech perception

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    Lynne E Bernstein

    2014-12-01

    Full Text Available This paper examines the questions, what levels of speech can be perceived visually, and how is visual speech represented by the brain? Review of the literature leads to the conclusions that every level of psycholinguistic speech structure (i.e., phonetic features, phonemes, syllables, words, and prosody can be perceived visually, although individuals differ in their abilities to do so; and that there are visual modality-specific representations of speech qua speech in higher-level vision brain areas. That is, the visual system represents the modal patterns of visual speech. The suggestion that the auditory speech pathway receives and represents visual speech is examined in light of neuroimaging evidence on the auditory speech pathways. We outline the generally agreed-upon organization of the visual ventral and dorsal pathways and examine several types of visual processing that might be related to speech through those pathways, specifically, face and body, orthography, and sign language processing. In this context, we examine the visual speech processing literature, which reveals widespread diverse patterns activity in posterior temporal cortices in response to visual speech stimuli. We outline a model of the visual and auditory speech pathways and make several suggestions: (1 The visual perception of speech relies on visual pathway representations of speech qua speech. (2 A proposed site of these representations, the temporal visual speech area (TVSA has been demonstrated in posterior temporal cortex, ventral and posterior to multisensory posterior superior temporal sulcus (pSTS. (3 Given that visual speech has dynamic and configural features, its representations in feedforward visual pathways are expected to integrate these features, possibly in TVSA.

  10. Imaging the Visual Pathway in Neuromyelitis Optica

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    Caspar F. Pfueller

    2011-01-01

    Full Text Available The focus of this paper is to summarize the current knowledge on visual pathway damage in neuromyelitis optica (NMO assessed by magnetic resonance imaging (MRI and optical coherence tomography (OCT.

  11. Imaging the visual pathway in neuromyelitis optica

    OpenAIRE

    Pfueller, Caspar F.; Friedemann Paul

    2011-01-01

    The focus of this paper is to summarize the current knowledge on visual pathway damage in neuromyelitis optica (NMO) assessed by magnetic resonance imaging (MRI) and optical coherence tomography (OCT).

  12. A Technique of Improved Medial Meniscus Visualization by Anterior Cruciate Ligament Graft Placement in Chronic Anterior Cruciate Deficient Knees.

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    Vertullo, Christopher J; Wijenayake, Lahann; Grayson, Jane E

    2016-04-01

    It is customary to perform medial meniscus repair before anterior cruciate ligament (ACL) graft placement when undertaken as a combined procedure. However, in chronic ACL-deficient knees, intraoperative anterior tibiofemoral translation can cause the medial meniscus repair to be more technically challenging. Intraoperative anterior tibiofemoral translation can both reduce the visualization of the medial meniscus and make its reduction unstable. An operative sequence alteration of ACL graft placement and tensioning before medial meniscal repair improves medial meniscus visualization in chronically ACL-deficient knees by using the ACL graft's ability to prevent anterior tibiofemoral translation. The technique sequence is as follows: (a) the medial meniscus is reduced, (b) ACL reconstruction is undertaken using a hamstring graft without final tibia fixation,

  13. Attentional effects in the visual pathways

    DEFF Research Database (Denmark)

    Bundesen, Claus; Larsen, Axel; Kyllingsbæk, Søren

    2002-01-01

    Attentional effects in the visual pathways were investigated by contrasting the distribution of regional cerebral blood flow (rCBF) measured by H(2)(15)O positron emission tomography (PET) during performance of a shape-matching task with the distribution of rCBF during a less demanding color...... and middle temporal gyri. The attentional effects found by the shape-color comparison in the thalamus and the primary visual cortex may have been generated by feedback signals preserving visual representations of selected stimuli in short-term memory....

  14. Boston keratoprosthesis and Ahmed glaucoma valve for visual rehabilitation in congenital anterior staphyloma

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    Bhaskar Srinivasan

    2012-01-01

    Full Text Available Congenital anterior staphyloma entails grave visual prognosis. The majority of reported patients have undergone enucleation. We report a promising result of staphylectomy with implantation of a keratoprosthesis and a glaucoma drainage device in a seven-month-old child with a large, congenital anterior staphyloma.

  15. Tbx2 regulates anterior neural specification by repressing FGF signaling pathway.

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    Cho, Gun-Sik; Park, Dong-Seok; Choi, Sun-Cheol; Han, Jin-Kwan

    2017-01-15

    During early embryogenesis, FGF signals regulate the antero-posterior (AP) patterning of the neural plate by promoting posterior cell fates. In particular, BMP signal-mediated attenuation of FGF pathway plays a critical role in the determination of the anterior neural region. Here we show that Tbx2, a T-box transcriptional repressor regulates anterior neural specification by suppressing FGF8 signaling pathway in Xenopus embryo. Tbx2 is expressed in the anterior edge of the neural plate in early neurulae. Overexpression and knockdown of Tbx2 induce expansion and reduction in the expression of anterior neural markers, respectively. It also suppresses FGF8-induced ERK phosphorylation and neural caudalization. Tbx2, which is a target gene of BMP signal, down-regulates FGF8 signaling by inhibiting the expression of Flrt3, a positive regulator of this pathway. We found that Tbx2 binds directly to the T-box element located in the promoter region of Flrt3 gene, thereby interfering with the activity of the promoter. Consistently, Tbx2 augmentation of anterior neural formation is inhibited by co-expression of Flrt3. Furthermore, disruption of the anterior-most structures such as eyes in Tbx2-depleted embryos can be rescued by inhibition of Flrt3 function or FGF signaling. Taken together, our results suggest that Tbx2 mediates BMP signal to down-regulate FGF signaling pathway by repressing Flrt3 expression for anterior tissue formation.

  16. Epidural anterior petrosectomy with subdural visualization of sphenobasal vein via the anterior transpetrosal approach--technical case report.

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    Ichimura, Shinya; Yoshida, Kazunari; Kagami, Hiroshi; Inaba, Makoto; Orii, Maaya; Kitamura, Yohei; Saga, Isako; Toda, Masahiro

    2012-10-01

    The drainage of the superficial middle cerebral vein (SMCV) is classified into four subtypes. The sphenobasal vein (SBV) drains from the SMCV to the pterygoid venous plexus at the temporal skull base. Epidural procedures in the standard anterior transpetrosal approach (ATPA) may damage the route of the SBV. We report a case in which modified surgical procedures via the ATPA were used to preserve the SBV. A 45-year-old man complained of right facial pain. Magnetic resonance images revealed a right cerebellopontine tumor suggestive of an epidermoid cyst. Right carotid angiography revealed that the SMCV drained into the pterygoid venous plexus via the SBV. The convexity dura mater of the temporal lobe was cut and the anterior part of the temporal lobe was retracted subdurally. The SBV was visualized from the subdural side. The basal dura mater of the temporal lobe posterior to the SBV was cut and the posterior part of the temporal lobe was retracted epidurally. After dissecting the dura mater medial to the greater petrosal nerve and to the edge of the petrous apex, the petrous apex was exposed and drilled out without injuring the SBV. The superior petrous sinus and the tentorium were cut. The tumor compressed the root exit zone of the trigeminal nerve. The tumor was grossly totally removed. The modified ATPA (epidural anterior petrosectomy with subdural visualization of the SBV) is effective in preserving the SBV.

  17. Visual outcome after fractionated stereotactic radiation therapy of benign anterior skull base tumors

    DEFF Research Database (Denmark)

    Astradsson, Arnar; Wiencke, Anne Katrine; Munck af Rosenschold, Per;

    2014-01-01

    skull base meningiomas and 55 patients treated with FSRT for pituitary adenomas between January 1999 and December 2009 with at least 2 years follow-up were included. Patients were followed up prospectively with magnetic resonance imaging scans, visual acuity and visual field examinations. RION was found...... in four (10%) patients with anterior skull base meningiomas and seven patients (13%) with pituitary adenomas. The five-year actuarial freedom from 25% RION visual field loss was 94% following FSRT. Actuarial 2-, 5- and 10-year tumor control rates were 100, 88.4 and 64.5% for anterior skull base...... meningiomas and 100, 98.2 and 94.9% for pituitary adenomas, respectively. Patients with an impaired visual field function pre-FSRT were more likely to experience worsened function (p = 0.016). We found that RION, was a relatively uncommon event, in a large prospective cohort of patients that were...

  18. Developmental Reorganisation of Visual Motion Pathways

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    John Wattam-Bell

    2012-05-01

    Full Text Available In adults, visual form and motion activate independent networks of extrastriate areas which are roughly aligned with the ventral and dorsal streams, respectively. Using high-density steady-state ERPs, we have previously shown that the scalp topographies of infant form and motion responses are markedly different from those in adults, implying a substantial developmental reorganisation of the underlying cortical pathways. However, it is hard to discern the nature of this reorganisation from the ambiguous polarity and timing information available in steady-state ERPs. We have started to address this problem by measuring transient ERPs to motion onset. In adults, the transient ERP topography initially suggests activation of extrastriate cortex, but rapidly switches to a dominant focus over the occipital pole originating in V1 and/or V2. The infant ERP is similar to the initial phase of adult ERP, but lacks the sudden switch to a V1/V2-dominated topography. The implications of these results for the reorganisation of cortical motion pathways will be discussed, with particular focus on the idea that the adult V1/V2 component is mainly driven by feedback from extrastriate motion areas (eg, V5, and that these feedback signals are not present in the infant brain.

  19. The role of the retino-colliculo-extrastriate pathway in visual awareness and visual field recovery.

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    Bertini, Caterina; Grasso, Paolo A; Làdavas, Elisabetta

    2016-09-01

    Patients with visual field defects resulting from post-chiasmatic lesions experience loss of visual function in up to one half of their visual field, with consequent impairments in their daily life activities. Therefore, effective strategies for compensating for the visual field loss are of great clinical relevance. After lesions to the primary visual pathway -which conveys visual information from the retina to the lateral geniculate nucleus, the optic radiations and, then, to the striate cortex-an alternative visual pathway, which projects from the superior colliculus to the extrastriate cortex, is usually spared in patients with visual field defects. In the present review, evidence for spared functioning of this alternative pathway in patients with visual field defects will be presented, both in terms of residual visual abilities, without awareness, for stimuli presented in the blind field, and the ability to integrate unseen visual signals presented in the blind field with concurrent auditory stimuli. Crucially, this review will discuss how the spared retino-colliculo-extrastriate pathway might be a useful tool for compensating for the loss of visual perception. Accordingly, evidence for the compensatory effects of systematic multisensory audio-visual stimulation in patients with visual field defects will be reviewed.

  20. 'What' Is Happening in the Dorsal Visual Pathway.

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    Freud, Erez; Plaut, David C; Behrmann, Marlene

    2016-10-01

    The cortical visual system is almost universally thought to be segregated into two anatomically and functionally distinct pathways: a ventral occipitotemporal pathway that subserves object perception, and a dorsal occipitoparietal pathway that subserves object localization and visually guided action. Accumulating evidence from both human and non-human primate studies, however, challenges this binary distinction and suggests that regions in the dorsal pathway contain object representations that are independent of those in ventral cortex and that play a functional role in object perception. We review here the evidence implicating dorsal object representations, and we propose an account of the anatomical organization, functional contributions, and origins of these representations in the service of perception.

  1. Optogenetics Advances in Primate Visual Pathway.

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    Jazayeri, Mehrdad; Remington, Evan

    2016-04-06

    In this issue of Neuron, Klein et al. (2016) used cell-type-specific optogenetics and electrical microstimulation to characterize the koniocellular geniculocortical projections in nonhuman primates. Their work offers a powerful platform for refining our understanding of the mechanisms of visual information processing in the lateral geniculate nucleus and primary visual cortex.

  2. Metabolic pathway visualization in living yeast by DNP-NMR.

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    Meier, Sebastian; Karlsson, Magnus; Jensen, Pernille R; Lerche, Mathilde H; Duus, Jens Ø

    2011-10-01

    Central carbon metabolism of living Saccharomyces cerevisiae is visualized by DNP-NMR. Experiments are conducted as real time assays that detect metabolic bottlenecks, pathway use, reversibility of reactions and reaction mechanisms in vivo with subsecond time resolution.

  3. Supporting curriculum development by visualizing a continuous learning pathway

    NARCIS (Netherlands)

    Schoonenboom, Judith; Oud, Wil

    2006-01-01

    Please, cite this publication as: Schoonenboom, J., & Oud, W. (2006). Supporting curriculum development by visualizing a continuous learning pathway. Proceedings of International Workshop in Learning Networks for Lifelong Competence Development, TENCompetence Conference. March 30th-31st, Sofia, Bulg

  4. Alzheimer disease: functional abnormalities in the dorsal visual pathway.

    LENUS (Irish Health Repository)

    Bokde, Arun L W

    2012-02-01

    PURPOSE: To evaluate whether patients with Alzheimer disease (AD) have altered activation compared with age-matched healthy control (HC) subjects during a task that typically recruits the dorsal visual pathway. MATERIALS AND METHODS: The study was performed in accordance with the Declaration of Helsinki, with institutional ethics committee approval, and all subjects provided written informed consent. Two tasks were performed to investigate neural function: face matching and location matching. Twelve patients with mild AD and 14 age-matched HC subjects were included. Brain activation was measured by using functional magnetic resonance imaging. Group statistical analyses were based on a mixed-effects model corrected for multiple comparisons. RESULTS: Task performance was not statistically different between the two groups, and within groups there were no differences in task performance. In the HC group, the visual perception tasks selectively activated the visual pathways. Conversely in the AD group, there was no selective activation during performance of these same tasks. Along the dorsal visual pathway, the AD group recruited additional regions, primarily in the parietal and frontal lobes, for the location-matching task. There were no differences in activation between groups during the face-matching task. CONCLUSION: The increased activation in the AD group may represent a compensatory mechanism for decreased processing effectiveness in early visual areas of patients with AD. The findings support the idea that the dorsal visual pathway is more susceptible to putative AD-related neuropathologic changes than is the ventral visual pathway.

  5. Visualization of the thymus in myasthenia gravis. Comparison between pneumomediastinography and CT of the anterior mediastinum

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    Komatsu, Midori; Tanaka, Makoto; Morimatsu, Mitsunori; Hirai, Shunsaku; Heshiki, Atsuko (Gunma Univ., Maebashi (Japan). School of Medicine)

    1982-12-01

    We investigated whether CT had any advantage over pneumomediastinography (PMG) for the visualization of thymus in twenty-one patients with myasthenia gravis (MG). In two cases of thymoma which had been suspected with chest radiography, CT demonstrated an anterior mediastinal tumor distinguishable from other mediastinal organs, and for these cases PMG was not performed. Excluding three patients who were submitted to PMG only, CT of the anterior mediastinum was carried out in sixteen patients of MG, revealing thymic shadows in seven (44%). PMG followed by conventional tomography was done subsequently in three of these seven cases, for whom thymectomy was indicated because of uncontrollable myasthenic symptoms, and in all patients finger-like thymic shadows were disclosed. The vertical extension of thymus was more easily demonstrable by PMG than CT. PMG was carried out in six of nine patients in whom CT was negative, and in all cases thymic shadows were obvious with subsequent conventional tomography. Consequently, false negative rate of CT was at least 38% (6/16) with regard to the visualization of the nontumorous thymus. Although CT of the anterior mediastinum is useful as a screening method because of its non-invasiveness, its negative result does not rule out an absence of the pathologic thymus in view of its high false negative rate. In this regard, PMG is still necessary for the final determination of the thymic configuration in the MG patients.

  6. Development of Network Analysis and Visualization System for KEGG Pathways

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    Dongmin Seo

    2015-07-01

    Full Text Available Big data refers to informationalization technology for extracting valuable information through the use and analysis of large-scale data and, based on that data, deriving plans for response or predicting changes. With the development of software and devices for next generation sequencing, a vast amount of bioinformatics data has been generated recently. Also, bioinformatics data based big-data technology is rising rapidly as a core technology by the bioinformatician, biologist and big-data scientist. KEGG pathway is bioinformatics data for understanding high-level functions and utilities of the biological system. However, KEGG pathway analysis requires a lot of time and effort because KEGG pathways are high volume and very diverse. In this paper, we proposed a network analysis and visualization system that crawl user interest KEGG pathways, construct a pathway network based on a hierarchy structure of pathways and visualize relations and interactions of pathways by clustering and selecting core pathways from the network. Finally, we construct a pathway network collected by starting with an Alzheimer’s disease pathway and show the results on clustering and selecting core pathways from the pathway network.

  7. Spatial contrast sensitivity in unilateral cerebral ischaemic lesions involving the posterior visual pathway.

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    Bulens, C; Meerwaldt, J D; van der Wildt, G J; Keemink, C J

    1989-04-01

    Contrast sensitivity function was studied in 16 patients with unilateral ischaemic lesions involving the posterior visual pathway. Sixty-two percent of the patients showed contrast sensitivity loss in at least one eye for horizontal or vertical stimulus orientation. Visual perception was distorted in a qualitatively different way according to the anteroposterior site of the lesion. Patients with occipital or occipitotemporal lesions showed high spatial frequency selective losses and patients with temporal or parietal lesions low frequency selective losses. Stimulus orientation selectivity was observed in patients with lesions of the primary visual cortex as well as in patients with lesions anterior to the striate cortex. Contrast sensitivity orientation-selective losses were demonstrated in 14 of the 17 'affected' eyes.

  8. Visual pathways involvement in clinically isolated syndrome in children

    Institute of Scientific and Technical Information of China (English)

    Vladislav; Voitenkov; Natalia; Skripchenko; Andrey; Klimkin

    2015-01-01

    AIM: To investigate extent and nature of visual pathways involvement in children with clinically isolated syndrome(CIS).METHODS: Forty-seven patients(age 11-17y) with CIS, which later proved to be multiple sclerosis(MS)onset, and 30 controls underwent visual evoked potentials(VEP) investigation within 12 d from the appearance of the first signs of disease. Latency and amplitude of P100 peak were compared with normative data and between groups.RESULTS: In 58% patients, including those without signs of retrobulbar neuritis, significant slowing of conduction along the central visual pathways(P100latency lengthening) is seen. P100 amplitudes drop(signs of axonal damage) are registered less frequently(29% cases).CONCLUSION: The results indicate that visual pathways are often affected in the MS onset; mostly demyelination signs are seen. Despite MRI significance for MS diagnostic, VEPs proved to be still effective in early diagnosis of MS in children.

  9. The anterior bias in visual art: the case of images of animals.

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    Bertamini, Marco; Bennett, Kate M; Bode, Carole

    2011-11-01

    Composition is an important topic in visual art. The literature suggests a bias for objects on the right side (Levy, 1976) and two additional biases with respect to positioning of objects within a rectangular frame: a Centre bias and an Inward bias (Palmer, Gardner, & Wickens, 2008). We analysed images of animals from three datasets of works of art: two datasets were from artists well known for their portraits of animals (Bewick, Stubbs) and the third was a medieval bestiary. There was no overall displacement of the subject to the right or to the left of the picture. However, we found a bias consisting of more space in front compared to behind the animal, consistent with Palmer at al.'s findings and with their definition of an Inward bias. Because our animals never face towards the centre we use the term Anterior bias. In addition, we found a modulation of this bias on the basis of the facing direction of the animal, consisting of a stronger Anterior bias for left-facing animals. This asymmetry may originate from a combination of an Anterior bias and a Right bias. Finally, with respect to size we found that the size of the animals predicted the proportion of the picture occupied, an effect known as "canonical size".

  10. The correlation between variation of visual acuity and the anterior chamber depth in the early period after phacoemulsification

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    Kai-jian CHEN

    2011-04-01

    Full Text Available Objective To investigate the correlation between the visual acuity variation and the anterior chamber depth in the early period after phacoemulsification.Methods Thirty-six eyes of 32 patients with age-related cataract underwent 3.2mm clear corneal incision phacoemulsification and intraocular lens(IOL implantation.The visual acuity was examined and horizontal curvature(K1,vertical curvature(K2,corneal astigmatism,and anterior chamber depth were measured with IOL-master preoperatively and also on 1,3,7 and 15 postoperative days.The changes in parameters were compared,and the correlations among visual acuity,corneal astigmatism and anterior chamber depth were analyzed.Results Before operation and 1d,3d,7d and 15d after operation,the corneal astigmatism was-0.87±0.40D,-1.92±1.38D,-1.69±1.13D,-1.45±0.79D and-1.36±0.74D;the anterior chamber depth was 3.08±0.35mm,4.04±0.38mm,4.28±0.29mm,4.22±0.17mm and 4.22±0.16mm;the visual acuity was 0.18±0.10,0.44±0.14,0.59±0.12,0.61±0.11 and 0.62±0.14.Significant difference was found between pre-operative and postoperative visual acuity,corneal astigmatism and anterior chamber depth,and it was also found in corneal astigmatism between 1d and 15d post operation(P < 0.05,as well as in anterior chamber depth and visual acuity between 1d and 3d post operation(P < 0.05.A positive correlation was found between visual acuity and corneal astigmatism on 1d(r=0.42,P < 0.05,3d(r=0.35,P < 0.05 and 7d(r=0.35,P < 0.05 post operation;and a negative correlation was found between visual acuity and anterior chamber depth on 3d(r=-0.29,P < 0.05,7d(r=-0.43,P < 0.01 and 15d(r=-0.37,P < 0.05 post operation.Conclusion Both the corneal astigmatism and the anterior chamber depth are correlated with the visual acuity variation in the early period after phacoemulsification.

  11. Reconstruction and dissection of the entire human visual pathway using diffusion tensor MRI

    Directory of Open Access Journals (Sweden)

    Sabine Hofer

    2010-04-01

    Full Text Available The human visual system comprises elongated fiber pathways that represent a serious challenge for diffusion tensor imaging (DTI and fiber tractography: while tracking of frontal fiber bundles may be compromised by the nearby presence of air-filled cavities, nerves, and eye muscles, the anatomic courses of the three main fiber bundles of the optic radiation are subject to pronounced inter-subject variability. Here, tractography of the entire visual pathway was achieved in 6 healthy subjects at high spatial accuracy, that is at 1.8 mm isotropic spatial resolution, without susceptibility-induced distortions, and in direct correspondence to anatomic MRI structures. Using a newly developed diffusion-weighted single-shot STEAM MRI sequence, we were able to track the thin optic nerve including the nasal optic nerve fibers, which cross the optic chiasm, and to dissect the optic radiation into the anterior ventral bundle (Meyer’s loop, the central bundle, and the dorsal bundle. Apart from scientific applications these results in single subjects promise advances in the planning of neurosurgical procedures to avoid unnecessary damage to the visual fiber system.

  12. Population coding of visual space: comparison of spatial representations in the dorsal and ventral pathways

    Directory of Open Access Journals (Sweden)

    Anne B Sereno

    2011-02-01

    Full Text Available Although the representation of space is as fundamental to visual processing as the representation of shape, it has received relatively little attention from neurophysiological investigations. In this study we characterize representations of space within visual cortex, and examine how they differ in a first direct comparison between dorsal and ventral subdivisions of the visual pathways. Neural activities were recorded in anterior inferotemporal cortex (AIT and lateral intraparietal cortex (LIP of awake behaving monkeys, structures associated with the ventral and dorsal visual pathways respectively, as a stimulus was presented at different locations within the visual field. In spatially selective cells, we find greater modulation of cell responses in LIP with changes in stimulus position. Further, using a novel population-based statistical approach (namely, multidimensional scaling, we recover the spatial map implicit within activities of neural populations, allowing us to quantitatively compare the geometry of neural space with physical space. We show that a population of spatially selective LIP neurons, despite having large receptive fields, is able to almost perfectly reconstruct stimulus locations within a low-dimensional representation. In contrast, a population of AIT neurons, despite each cell being spatially selective, provide less accurate low-dimensional reconstructions of stimulus locations. They produce instead only a topologically (categorically correct rendition of space, which nevertheless might be critical for object and scene recognition. Furthermore, we found that the spatial representation recovered from population activity shows greater translation invariance in LIP than in AIT. We suggest that LIP spatial representations may be dimensionally isomorphic with 3D physical space, while in AIT spatial representations may reflect a more categorical representation of space (e.g., next to or above.

  13. Abnormal white matter tractography of visual pathways detected by high-angular-resolution diffusion imaging (HARDI) corresponds to visual dysfunction in cortical/cerebral visual impairment

    OpenAIRE

    Bauer, Corinna M.; Heidary, Gena; Koo, Bang-Bon; Killiany, Ronald J.; Bex, Peter; Merabet, Lotfi B.

    2014-01-01

    Cortical (cerebral) visual impairment (CVI) is characterized by visual dysfunction associated with damage to the optic radiations and/or visual cortex. Typically it results from pre- or perinatal hypoxic damage to postchiasmal visual structures and pathways. The neuroanatomical basis of this condition remains poorly understood, particularly with regard to how the resulting maldevelopment of visual processing pathways relates to observations in the clinical setting. We report our investigation...

  14. Are flash-evoked visual potentials useful for intraoperative monitoring of visual pathway function?

    Science.gov (United States)

    Cedzich, C; Schramm, J; Fahlbusch, R

    1987-11-01

    Flash-evoked visual potentials (VEPs) recorded from the scalp were used in a series of 35 patients with tumors along the visual pathway: 3 orbital tumors, 25 perisellar tumors, 4 intraventricular tumors, and 3 occipital lesions. Preoperatively, various combinations of impaired visual fields and visual acuity were observed in over 90% of the patients. A postoperative decrease in visual function was observed in 3 cases. Of the 25 perisellar lesions, 13 were operated through a standard frontotemporal craniotomy and 12 were operated through a transnasal-transsphenoidal approach. VEPs were highly susceptible to volatile anesthetics, and there was a significant incidence of spontaneous latency increases and amplitude decreases in a large number of patients. There was an unacceptably high number of cases with significant VEP alteration occurring without concomitant visual function change. During trepanation or the transnasal approach, a reversible potential loss was observed in 11 patients, a profoundly altered wave form was seen in 8 cases, and a loss of single peaks was observed in 15 patients. During dissection of the tumor, a reversible potential loss or a potential with unidentifiable peaks was found in 25 cases; however, the VEPs recovered during closure or in the recovery room. There was no correlation between intraoperative VEP changes and the postoperative changes in visual function. In only 1 patient with an insignificant postoperative decrease in visual acuity from 0.4 to 0.3 was there a concomitant intraoperative potential loss. The major conclusion of our findings is that light-emitting diode flash-evoked VEPs demonstrate intraoperative changes that appear too early and too prominently to be caused solely by manipulation of the optic pathways.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Visualization of torn anterior cruciate ligament using 3-dimensional computed tomography

    Directory of Open Access Journals (Sweden)

    Hiroaki Uozumi

    2013-07-01

    Full Text Available Recently, a remnant-preserving anterior cruciate ligament (ACL reconstruction technique has been developed. However, the pre-operative condition of remnant ACL is occasionally difficult to evaluate by magnetic resonance imaging. The purpose of this study is to evaluate the accuracy of pre-operative visualization of remnant ACL using three-dimensional computed tomography (3D-CT. The remnant ACL in 25 patients was examined by 3D-CT before ACL reconstruction surgery. Findings on 3D-CT images and arthroscopy were compared. The 3D-CT images were classified into 4 groups: Group A, remnant fibers attached to the posterior cruciate ligament (PCL; Group B, those located between the PCL and the lateral wall; Group C, those attached to the lateral wall; and Group D, no identifiable remnant fibers on the tibial side. These groups were made up of 4, 3, 9 and 9 patients, respectively. Findings on 3D-CT images were identical to those during arthroscopy in 20 of 25 cases (80%. Remnant ACL can be accurately evaluated using 3D-CT in 80% of cases of torn ACL. This novel method is a useful technique for pre-operative assessment of remnant ACL.

  16. Advanced Data Visualization in Astrophysics: The X3D Pathway

    Science.gov (United States)

    Vogt, Frédéric P. A.; Owen, Chris I.; Verdes-Montenegro, Lourdes; Borthakur, Sanchayeeta

    2016-02-01

    Most modern astrophysical data sets are multi-dimensional; a characteristic that can nowadays generally be conserved and exploited scientifically during the data reduction/simulation and analysis cascades. However, the same multi-dimensional data sets are systematically cropped, sliced, and/or projected to printable two-dimensional diagrams at the publication stage. In this article, we introduce the concept of the “X3D pathway” as a mean of simplifying and easing the access to data visualization and publication via three-dimensional (3D) diagrams. The X3D pathway exploits the facts that (1) the X3D 3D file format lies at the center of a product tree that includes interactive HTML documents, 3D printing, and high-end animations, and (2) all high-impact-factor and peer-reviewed journals in astrophysics are now published (some exclusively) online. We argue that the X3D standard is an ideal vector for sharing multi-dimensional data sets because it provides direct access to a range of different data visualization techniques, is fully open source, and is a well-defined standard from the International Organization for Standardization. Unlike other earlier propositions to publish multi-dimensional data sets via 3D diagrams, the X3D pathway is not tied to specific software (prone to rapid and unexpected evolution), but instead is compatible with a range of open-source software already in use by our community. The interactive HTML branch of the X3D pathway is also actively supported by leading peer-reviewed journals in the field of astrophysics. Finally, this article provides interested readers with a detailed set of practical astrophysical examples designed to act as a stepping stone toward the implementation of the X3D pathway for any other data set.

  17. Advanced Data Visualization in Astrophysics: the X3D Pathway

    CERN Document Server

    Vogt, F P A; Verdes-Montenegro, L; Borthakur, S

    2015-01-01

    Most modern astrophysical datasets are multi-dimensional; a characteristic that can nowadays generally be conserved and exploited scientifically during the data reduction/simulation and analysis cascades. Yet, the same multi-dimensional datasets are systematically cropped, sliced and/or projected to printable two-dimensional (2-D) diagrams at the publication stage. In this article, we introduce the concept of the "X3D pathway" as a mean of simplifying and easing the access to data visualization and publication via three-dimensional (3-D) diagrams. The X3D pathway exploits the facts that 1) the X3D 3-D file format lies at the center of a product tree that includes interactive HTML documents, 3-D printing, and high-end animations, and 2) all high-impact-factor & peer-reviewed journals in Astrophysics are now published (some exclusively) online. We argue that the X3D standard is an ideal vector for sharing multi-dimensional datasets, as it provides direct access to a range of different data visualization tec...

  18. Visual motion serves but is not under the purview of the dorsal pathway.

    Science.gov (United States)

    Gilaie-Dotan, Sharon

    2016-08-01

    Visual motion processing is often attributed to the dorsal visual pathway despite visual motion's involvement in almost all visual functions. Furthermore, some visual motion tasks critically depend on the structural integrity of regions outside the dorsal pathway. Here, based on numerous studies, I propose that visual motion signals are swiftly transmitted via multiple non-hierarchical routes to primary motion-dedicated processing regions (MT/V5 and MST) that are not part of the dorsal pathway, and then propagated to a multiplicity of brain areas according to task demands, reaching these regions earlier than the dorsal/ventral hierarchical flow. This not only places MT/V5 at the same or even earlier visual processing stage as that of V1, but can also elucidate many findings with implications to visual awareness. While the integrity of the non-hierarchical motion pathway is necessary for all visual motion perception, it is insufficient on its own, and the transfer of visual motion signals to additional brain areas is crucial to allow the different motion perception tasks (e.g. optic flow, visuo-vestibular balance, movement observation, dynamic form detection and perception, and even reading). I argue that this lateral visual motion pathway can be distinguished from the dorsal pathway not only based on faster response latencies and distinct anatomical connections, but also based on its full field representation. I also distinguish between this primary lateral visual motion pathway sensitive to all motion in the visual field, and a much less investigated optic flow sensitive medial processing pathway (from V1 to V6 and V6A) that appears to be part of the dorsal pathway. Multiple additional predictions are provided that allow testing this proposal and distinguishing between the visual pathways.

  19. Dissecting Nck/Dock Signaling Pathways in Drosophila Visual System

    Directory of Open Access Journals (Sweden)

    2005-04-01

    Full Text Available The establishment of neuronal connections during embryonic development requires the precise guidance and targeting of the neuronal growth cone, an expanded cellular structure at the leading tip of a growing axon. The growth cone contains sophisticated signaling systems that allow the rapid communication between guidance receptors and the actin cytoskeleton in generating directed motility. Previous studies demonstrated a specific role for the Nck/Dock SH2/SH3 adapter protein in photoreceptor (R cell axon guidance and target recognition in the Drosophila visual system, suggesting strongly that Nck/Dock is one of the long-sought missing links between cell surface receptors and the actin cytoskeleton. In this review, I discuss the recent progress on dissecting the Nck/Dock signaling pathways in R-cell growth cones. These studies have identified additional key components of the Nck/Dock signaling pathways for linking the receptor signaling to the remodeling of the actin cytoskeleton in controlling growth-cone motility.

  20. Pediatric anterior cruciate ligament femoral fixation: the trans-iliotibial band endoscopic portal for direct visualization of ideal button placement.

    Science.gov (United States)

    Mistovich, R Justin; O'Toole, Patrick O J; Ganley, Theodore J

    2014-06-01

    Pediatric and adolescent anterior cruciate ligament reconstruction is a commonly performed procedure that has been increasing in incidence. Multiple techniques for graft fixation have been described. Button-based femoral cortical suspension fixation of the anterior cruciate ligament graft allows for fast, secure fixation with strong load-to-failure biomechanical properties. The biomechanical properties of button-based femoral cortical suspension fixation are especially beneficial with soft-tissue grafts such as hamstring autografts. Confirmation of a successfully flipped button can be achieved with intraoperative fluoroscopy or indirect viewing; however, these techniques do not provide direct visualization of the flipped button. Our trans-iliotibial band endoscopic portal allows the surgeon to safely and directly visualize the flipped button on the lateral femoral cortex and ensure that there is no malpositioning in the form of an incompletely flipped button or from soft-tissue interposition between the button and the lateral femoral cortex. This portal therefore allows for direct visual confirmation that the button is fully flipped and resting flush against the femoral cortex, deep to the iliotibial band and vastus lateralis.

  1. The Impact of Density and Ratio on Object-Ensemble Representation in Human Anterior-Medial Ventral Visual Cortex.

    Science.gov (United States)

    Cant, Jonathan S; Xu, Yaoda

    2015-11-01

    Behavioral research has demonstrated that observers can extract summary statistics from ensembles of multiple objects. We recently showed that a region of anterior-medial ventral visual cortex, overlapping largely with the scene-sensitive parahippocampal place area (PPA), participates in object-ensemble representation. Here we investigated the encoding of ensemble density in this brain region using fMRI-adaptation. In Experiment 1, we varied density by changing the spacing between objects and found no sensitivity in PPA to such density changes. Thus, density may not be encoded in PPA, possibly because object spacing is not perceived as an intrinsic ensemble property. In Experiment 2, we varied relative density by changing the ratio of 2 types of objects comprising an ensemble, and observed significant sensitivity in PPA to such ratio change. Although colorful ensembles were shown in Experiment 2, Experiment 3 demonstrated that sensitivity to object ratio change was not driven mainly by a change in the ratio of colors. Thus, while anterior-medial ventral visual cortex is insensitive to density (object spacing) changes, it does code relative density (object ratio) within an ensemble. Object-ensemble processing in this region may thus depend on high-level visual information, such as object ratio, rather than low-level information, such as spacing/spatial frequency.

  2. Neural-metabolic coupling in the central visual pathway.

    Science.gov (United States)

    Freeman, Ralph D; Li, Baowang

    2016-10-05

    Studies are described which are intended to improve our understanding of the primary measurements made in non-invasive neural imaging. The blood oxygenation level-dependent signal used in functional magnetic resonance imaging (fMRI) reflects changes in deoxygenated haemoglobin. Tissue oxygen concentration, along with blood flow, changes during neural activation. Therefore, measurements of tissue oxygen together with the use of a neural sensor can provide direct estimates of neural-metabolic interactions. We have used this relationship in a series of studies in which a neural microelectrode is combined with an oxygen micro-sensor to make simultaneous co-localized measurements in the central visual pathway. Oxygen responses are typically biphasic with small initial dips followed by large secondary peaks during neural activation. By the use of established visual response characteristics, we have determined that the oxygen initial dip provides a better estimate of local neural function than the positive peak. This contrasts sharply with fMRI for which the initial dip is unreliable. To extend these studies, we have examined the relationship between the primary metabolic agents, glucose and lactate, and associated neural activity. For this work, we also use a Doppler technique to measure cerebral blood flow (CBF) together with neural activity. Results show consistent synchronously timed changes such that increases in neural activity are accompanied by decreases in glucose and simultaneous increases in lactate. Measurements of CBF show clear delays with respect to neural response. This is consistent with a slight delay in blood flow with respect to oxygen delivery during neural activation.This article is part of the themed issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'.

  3. Role of white-matter pathways in coordinating alpha oscillations in resting visual cortex.

    Science.gov (United States)

    Hindriks, R; Woolrich, M; Luckhoo, H; Joensson, M; Mohseni, H; Kringelbach, M L; Deco, G

    2015-02-01

    In the absence of cognitive tasks and external stimuli, strong rhythmic fluctuations with a frequency ≈ 10 Hz emerge from posterior regions of human neocortex. These posterior α-oscillations can be recorded throughout the visual cortex and are particularly strong in the calcarine sulcus, where the primary visual cortex is located. The mechanisms and anatomical pathways through which local \\alpha-oscillations are coordinated however, are not fully understood. In this study, we used a combination of magnetoencephalography (MEG), diffusion tensor imaging (DTI), and biophysical modeling to assess the role of white-matter pathways in coordinating cortical α-oscillations. Our findings suggest that primary visual cortex plays a special role in coordinating α-oscillations in higher-order visual regions. Specifically, the amplitudes of α-sources throughout visual cortex could be explained by propagation of α-oscillations from primary visual cortex through white-matter pathways. In particular, α-amplitudes within visual cortex correlated with both the anatomical and functional connection strengths to primary visual cortex. These findings reinforce the notion of posterior α-oscillations as intrinsic oscillations of the visual system. We speculate that they might reflect a default-mode of the visual system during which higher-order visual regions are rhythmically primed for expected visual stimuli by α-oscillations in primary visual cortex.

  4. Cerebral Visual Impairment: Which Perceptive Visual Dysfunctions Can Be Expected in Children with Brain Damage? A Systematic Review

    Science.gov (United States)

    Boot, F. H.; Pel, J. J. M.; van der Steen, J.; Evenhuis, H. M.

    2010-01-01

    The current definition of Cerebral Visual Impairment (CVI) includes all visual dysfunctions caused by damage to, or malfunctioning of, the retrochiasmatic visual pathways in the absence of damage to the anterior visual pathways or any major ocular disease. CVI is diagnosed by exclusion and the existence of many different causes and symptoms make…

  5. Anterior wrist and medial malleolus as the novel sites of tissue selection: a retrospective study on electric shock death through the hand-to-foot circuit pathway.

    Science.gov (United States)

    Xu, Guangtao; Su, Ruibing; Lv, Junyao; Hu, Bo; Gu, Huan; Li, Xianxian; Gu, Jiang; Yu, Xiaojun

    2017-01-06

    Our previous work demonstrated that characteristic changes could occur in the anterior wrist and medial malleolus in electric deaths through the hand-to-foot electric circuit pathway in an electric shock rat model. However, whether the same phenomenon occurs in humans is unknown. The aim of the present retrospective study was to ascertain whether the anterior wrist and medial malleolus could also be selected as the promising and significant sites in electric death through the hand-to-foot circuit pathway. Nineteen human cases from the autopsy and one clinical survivor who sustained a severe electric shock through the hand-to-foot circuit pathway were analyzed. Additional ten autopsy patients who died from traffic accidents and sudden cardiac attacks were used as the control group. Histopathological changes in the soft tissues of the anterior wrist and medial malleolus in all autopsy patients, as well as the electric current pathway of the survivor, were observed. The results showed that the nuclear polarizations in the anterior wrist and medial malleolus soft tissues of the electric death were extremely noticeable as compared with the controls. The most severe electrical injury in the survivor occurred in the anterior wrist. These findings suggest that the soft tissues of the anterior wrist and/or the medial malleolus as the narrowest parts of the limbs could be used as the complementary sites for tissue selection and considered as necessary locations for examinations to assess the electric death in medicolegal identification.

  6. Visualization of Tear Clearance Using Anterior Segment Optical Coherence Tomography and Polymethylmethacrylate Particles.

    Science.gov (United States)

    Zheng, Xiaodong; Yamaguchi, Masahiko; Kamao, Tomoyuki; Sakane, Yuri; Goto, Tomoko; Shiraishi, Atsushi; Ohashi, Yuichi

    2016-11-01

    We previously reported 2 new methods, anterior segment optical coherence tomography (AS-OCT) and polymethylmethacrylate particles suspended in fluorescein solution (PPF), for the evaluation of tear clearance and rapid tear flow after blinking (tear Krehbiel flow). Here, we investigated age-related OCT tear clearance and tear film thickness (TFT) and the potential correlation of OCT tear clearance and PPF velocity indicative of tear Krehbiel flow. Normal subjects separated into young and older groups received 5 μL of saline solution into the lower conjunctival sac, and an image of the central lower eyelid tear meniscus was captured by AS-OCT immediately and 30 seconds after natural blinking. Tear meniscus height (TMH) and tear meniscus area (TMA) were measured, and their percentage decrease was defined as OCT clearance rate. A Spectralis OCT Anterior Segment Module captured the central corneal tear film layer for TFT measurements. OCT clearance rates were significantly higher in young versus older subjects (P = 0.0002). When all subjects were analyzed, age was significantly and negatively correlated with TMH clearance rate (r = -0.4928, P = 0.0003) and TMA clearance rate (r = -0.4596, P = 0.0008). TFT values were significantly and negatively correlated with age (r = -0.6662, P clearance rates and PPF velocity (TMH rate: r = 0.2926, P = 0.0392; TMA rate: r = 0.3274, P = 0.0205). AS-OCT and PPF might be novel techniques for quantitative evaluation of tear clearance and Krehbiel flow.

  7. Object Domain and Modality in the Ventral Visual Pathway.

    Science.gov (United States)

    Bi, Yanchao; Wang, Xiaoying; Caramazza, Alfonso

    2016-04-01

    The nature of domain-specific organization in higher-order visual cortex (ventral occipital temporal cortex, VOTC) has been investigated both in the case of visual experience deprivation and of modality of stimulation in sighted individuals. Object domain interacts in an intriguing and revelatory way with visual experience and modality of stimulation: selectivity for artifacts and scene domains is largely immune to visual deprivation and is multi-modal, whereas selectivity for animate items in lateral posterior fusiform gyrus is present only with visual stimulation. This domain-by-modality interaction is not readily accommodated by existing theories of VOTC representation. We conjecture that these effects reflect a distinction between the visual features that characterize different object domains and their interaction with different types of downstream computational systems.

  8. Case study: visualization and analysis of mitogen-activated protein kinase pathways in the literature

    Science.gov (United States)

    Lee, Changsu; Park, Jinah; Park, Jong C.

    2004-06-01

    Data sets of up to 3000 journal abstracts from MEDLINE literature on the keyword combination `MAPK pathway' and `human' are visualized and analyzed for mitogen-activated protein kinase (MAPK) pathways. We have tightly coupled exploratory visualization with information extraction for interactive navigation through scattered information sources, in search of useful facts on MAPK by frequency-based filtering and amplification. Unlike direct database visualization that operates on curated data sets, literature visualization has the advantages of manipulating data sets of a massive scale with a lot less manpower and effectively responding to the fast cycles of the developments in the field.

  9. Alterations of the visual pathways in congenital blindness

    DEFF Research Database (Denmark)

    Ptito, Maurice; Schneider, Fabien C G; Paulson, Olaf B

    2008-01-01

    We used whole brain MRI voxel-based morphometry (VBM) to study the anatomical organization of the visual system in congenitally blind (CB) adults. Eleven CB without a history of visual perception were compared with 21 age- and sex-matched normal-sighted controls (NS). CB showed significant atrophy...... projections to the visual cortex in CB are largely atrophied. Despite the massive volume reductions in the occipital lobes, there is compelling evidence from the literature (reviewed in Noppeney 2007; Ptito and Kupers 2005) that blind subjects activate their visual cortex when performing tasks that involve...

  10. Diode Laser 810 Nm as a Potential Treatment to Improve Visual Function in Nonarteritic Anterior Ischemic Optic Neuropathy (NAION

    Directory of Open Access Journals (Sweden)

    Mohammad Hossein Heidari

    2011-01-01

    Full Text Available Nonarteritic anterior ischemic optic neuropathy (NAION is one of the most widespread visually disabling diseases in the middle-aged and elderly population. The optic nerve damage appears to result from a perfusion insufficiency in the short posterior ciliary arteries leading to infarction of the retrolaminar portion of the optic disc. Induced Heat shock protein (Hsp is known to have neuroprotective effects against ischemic injury of the central nervous system in mammals. Transpupillary thermotherapy (TTT application to the optic nerve head induces Hsp70 expression. We hypothesize that Transpupillary thermotherapy (TTT could be a novel method for improving and preserving the function of the optic nerve fibers in the eye with NAION. An 810-nm diode laser beam is focused to the center of the optic nerve head to induce Hsp. Controlled prospective and randomized clinical trial is necessary to confirm conclusively the effectiveness of this method.

  11. Two Visual Pathways in Primates Based on Sampling of Space: Exploitation and Exploration of Visual Information.

    Science.gov (United States)

    Sheth, Bhavin R; Young, Ryan

    2016-01-01

    Evidence is strong that the visual pathway is segregated into two distinct streams-ventral and dorsal. Two proposals theorize that the pathways are segregated in function: The ventral stream processes information about object identity, whereas the dorsal stream, according to one model, processes information about either object location, and according to another, is responsible in executing movements under visual control. The models are influential; however recent experimental evidence challenges them, e.g., the ventral stream is not solely responsible for object recognition; conversely, its function is not strictly limited to object vision; the dorsal stream is not responsible by itself for spatial vision or visuomotor control; conversely, its function extends beyond vision or visuomotor control. In their place, we suggest a robust dichotomy consisting of a ventral stream selectively sampling high-resolution/focal spaces, and a dorsal stream sampling nearly all of space with reduced foveal bias. The proposal hews closely to the theme of embodied cognition: Function arises as a consequence of an extant sensory underpinning. A continuous, not sharp, segregation based on function emerges, and carries with it an undercurrent of an exploitation-exploration dichotomy. Under this interpretation, cells of the ventral stream, which individually have more punctate receptive fields that generally include the fovea or parafovea, provide detailed information about object shapes and features and lead to the systematic exploitation of said information; cells of the dorsal stream, which individually have large receptive fields, contribute to visuospatial perception, provide information about the presence/absence of salient objects and their locations for novel exploration and subsequent exploitation by the ventral stream or, under certain conditions, the dorsal stream. We leverage the dichotomy to unify neuropsychological cases under a common umbrella, account for the increased

  12. Escher: A Web Application for Building, Sharing, and Embedding Data-Rich Visualizations of Biological Pathways

    DEFF Research Database (Denmark)

    King, Zachary A.; Draeger, Andreas; Ebrahim, Ali;

    2015-01-01

    Escher is a web application for visualizing data on biological pathways. Three key features make Escher a uniquely effective tool for pathway visualization. First, users can rapidly design new pathway maps. Escher provides pathway suggestions based on user data and genome-scale models, so users can......IP)-in conjunction with metabolite-and reaction-oriented data types (e.g. metabolomics, fluxomics). Third, Escher harnesses the strengths of web technologies (SVG, D3, developer tools) so that visualizations can be rapidly adapted, extended, shared, and embedded. This paper provides examples of each...... of these features and explains how the development approach used for Escher can be used to guide the development of future visualization tools....

  13. Reduction of Interhemispheric Functional Connectivity in Sensorimotor and Visual Information Processing Pathways in Schizophrenia

    Directory of Open Access Journals (Sweden)

    Xu Lang

    2016-01-01

    Conclusions: Interhemispheric functional connectivity in the sensorimotor and visual processing pathways was reduced in patients with schizophrenia, but this reduction was unrelated to the disease state; thus, this reduction may serve as a trait marker of schizophrenia.

  14. Evaluation of two treatment outcome prediction models for restoration of visual fields in patients with postchiasmatic visual pathway lesions.

    Science.gov (United States)

    Gall, Carolin; Steger, Benedikt; Koehler, Juergen; Sabel, Bernhard A

    2013-09-01

    Visual functions of patients with visual field defects after acquired brain injury affecting the primary visual pathway can be improved by means of vision restoration training. Since the extent of the restored visual field varies between patients, the prediction of treatment outcome and its visualization may help patients to decide for or against participating in therapies aimed at vision restoration. For this purpose, two treatment outcome prediction models were established based on either self-organizing maps (SOMs) or categorical regression (CR) to predict visual field change after intervention by several features that were hypothesized to be associated with vision restoration. Prediction was calculated for visual field changes recorded with High Resolution Perimetry (HRP). Both models revealed a similar predictive quality with the CR model being slightly more beneficial. Predictive quality of the SOM model improved when using only a small number of features that exhibited a higher association with treatment outcome than the remaining features, i.e. neighborhood activity and homogeneity within the surrounding 5° visual field of a given position, together with its residual function and distance to the scotoma border. Although both models serve their purpose, these were not able to outperform a primitive prediction rule that attests the importance of areas of residual vision, i.e. regions with partial visual field function, for vision restoration.

  15. Visual outcomes after deep anterior lamellar keratoplasty using donor corneas without removal of Descemet membrane and endothelium

    Directory of Open Access Journals (Sweden)

    Tatiana Moura Bastos Prazeres

    Full Text Available ABSTRACT Purpose: The optical quality of the interface after deep anterior lamellar keratoplasty (DALK using the big-bubble technique has been shown to be excellent, leading to results comparable to penetrating keratoplasty. However, there is little in the literature with respect to the controversy surrounding the preparation of the donor cornea. The purpose of this study was to evaluate visual acuity (VA in patients with keratoconus who underwent DALK without removal of the donor graft endothelium. Methods: The records of 90 patients who underwent DALK without the removal of the Descemet membrane (DM and endothelium were retrospectively reviewed. Data collected included uncorrected VA (UCVA and spectacle-corrected VA (SCVA at 7, 30, 180 days, and 1 year postoperatively. Contact lens-corrected visual acuity (CLVA was evaluated after 1 year of the procedure. Results: UCVA was significantly better than preoperative values at 7 days (p<0.001, 30 days (p<0.001, 180 days (p<0.001, and 1 year (p<0.001 after surgery. The 1-year postoperative mean SCVA and CLVA also improved when compared with preoperative SCVA (p<0.001 for both. Conclusions: DALK utilizing donor corneas with attached Descemet membrane and endothelium results in satisfactory VA in patients with keratoconus.

  16. [Diffusion tensor imaging of the visual pathway in glaucomatous optic nerve atrophy].

    Science.gov (United States)

    Engelhorn, T; A Schmidt, M; Dörfler, A; Michelson, G

    2017-03-01

    In Germany more than one million inhabitants suffer from glaucoma, more than 100,000 are threatened with blindness because glaucoma is often diagnosed too late or not at all. Diagnosis and monitoring is usually carried out "only" by examination of the retina and not the whole visual pathway. However, the eye is just "the tip of the iceberg" of the actual visual pathway, which extends through the brain to the visual cortex. The interdisciplinary holistic assessment of the whole visual pathway in glaucoma is of crucial importance because glaucoma is a complex neurodegenerative disease. Subtypes, such as normal tension glaucoma (NTG), seem to originate from primary damage to the intracranial visual pathway with secondary retrograde retinal degeneration. Recent studies including glaucoma patients and healthy controls could show that diffusion tensor imaging with calculation of diffusion coefficients, i.e. fractional anisotropy (FA), mean and radial diffusivity (MD and RD) as markers of axonal integrity, provide the potential to assess the intracranial visual pathway with a high correlation to established ophthalmological examinations. In particular, calculation of FA maps of the visual pathway and accompanying voxel-based approaches, can be integrated into clinical routine. Thus, detection of glaucoma-related intracranial alterations, even in early stages of the disease, as well as differentiation of different glaucoma subtypes, is made possible. Furthermore, the diagnosis of normal tension glaucoma seems to be possible much earlier with these new imaging techniques compared to established ophthalmological work-up. Moreover, holistic imaging provides new insights into the pathophysiology of this form of glaucoma. This review article gives an overview of these novel magnetic resonance imaging techniques for assessment of the visual pathway in glaucomatous optic nerve atrophy and reveals the potential of an interdisciplinary approach.

  17. Electrophysiological correlates of associative visual agnosia lesioned in the ventral pathway.

    Science.gov (United States)

    Yamasaki, Takao; Taniwaki, Takayuki; Tobimatsu, Shozo; Arakawa, Kenji; Kuba, Hiroshi; Maeda, Yoshihisa; Kuwabara, Yasuo; Shida, Kenshiro; Ohyagi, Yasumasa; Yamada, Takeshi; Kira, Jun-ichi

    2004-06-15

    Visual agnosia has been well studied by anatomical, neuropsychological and neuroimaging studies. However, functional changes in the brain have been rarely assessed by electrophysiological methods. We carried out electrophysiological examinations on a 23-year-old man with associative visual agnosia, prosopagnosia and cerebral achromatopsia to evaluate the higher brain dysfunctions of visual recognition. Electrophysiological methods consisted of achromatic, chromatic and category-specific visual evoked potentials (CS-VEPs), and event-related potentials (ERPs) with color and motion discrimination tasks. Brain magnetic resonance imaging revealed large white matter lesions in the bilateral temporo-occipital lobes involving the lingual and fusiform gyri (V4) and inferior longitudinal fasciculi due to multiple sclerosis. Examinations including CS-VEPs demonstrated dysfunctions of face and object perception while sparing semantic word perception after primary visual cortex (V1) in the ventral pathway. ERPs showed abnormal color perception in the ventral pathway with normal motion perception in the dorsal pathway. These electrophysiological findings were consistent with lesions in the ventral pathway that were detected by clinical and neuroimaging findings. Therefore, CS-VEPs and ERPs with color and motion discrimination tasks are useful methods for assessing the functional changes of visual recognition such as visual agnosia.

  18. Escher: A Web Application for Building, Sharing, and Embedding Data-Rich Visualizations of Biological Pathways.

    Directory of Open Access Journals (Sweden)

    Zachary A King

    2015-08-01

    Full Text Available Escher is a web application for visualizing data on biological pathways. Three key features make Escher a uniquely effective tool for pathway visualization. First, users can rapidly design new pathway maps. Escher provides pathway suggestions based on user data and genome-scale models, so users can draw pathways in a semi-automated way. Second, users can visualize data related to genes or proteins on the associated reactions and pathways, using rules that define which enzymes catalyze each reaction. Thus, users can identify trends in common genomic data types (e.g. RNA-Seq, proteomics, ChIP--in conjunction with metabolite- and reaction-oriented data types (e.g. metabolomics, fluxomics. Third, Escher harnesses the strengths of web technologies (SVG, D3, developer tools so that visualizations can be rapidly adapted, extended, shared, and embedded. This paper provides examples of each of these features and explains how the development approach used for Escher can be used to guide the development of future visualization tools.

  19. Escher: A Web Application for Building, Sharing, and Embedding Data-Rich Visualizations of Biological Pathways.

    Science.gov (United States)

    King, Zachary A; Dräger, Andreas; Ebrahim, Ali; Sonnenschein, Nikolaus; Lewis, Nathan E; Palsson, Bernhard O

    2015-08-01

    Escher is a web application for visualizing data on biological pathways. Three key features make Escher a uniquely effective tool for pathway visualization. First, users can rapidly design new pathway maps. Escher provides pathway suggestions based on user data and genome-scale models, so users can draw pathways in a semi-automated way. Second, users can visualize data related to genes or proteins on the associated reactions and pathways, using rules that define which enzymes catalyze each reaction. Thus, users can identify trends in common genomic data types (e.g. RNA-Seq, proteomics, ChIP)--in conjunction with metabolite- and reaction-oriented data types (e.g. metabolomics, fluxomics). Third, Escher harnesses the strengths of web technologies (SVG, D3, developer tools) so that visualizations can be rapidly adapted, extended, shared, and embedded. This paper provides examples of each of these features and explains how the development approach used for Escher can be used to guide the development of future visualization tools.

  20. Procrystal Analysis as a Tool for the Visualization of Ion Migration Pathways

    DEFF Research Database (Denmark)

    Filso, Mette O.; Eikeland, Espen; Iversen, Bo B.

    2016-01-01

    The procrystal analysis is presented as a valuable tool for fast, clear visualization of ion migration pathways in solids. The method has been shown to posses great predictive power for ion migration in Li-ion battery materials. Selected results for known Li-ion conductors are presented, including...... a new study of Li2CoPO4F. In addition, examples of visualization of Na-ion and K-ion migration pathways are displayed. A full procrystal analysis includes both visual representation of possible pathways and a ranking of these pathways according to their accessibility to migrating ions. Such an analysis...... can be performed in only a few minutes, making it the fastest choice available for the prediction of ion migration in solids at this time. Further applications include solid oxide fuel cells, and other research fields in which ion migration in crystalline solids plays a significant role....

  1. Multiple Sensory-Motor Pathways Lead to Coordinated Visual Attention

    Science.gov (United States)

    Yu, Chen; Smith, Linda B.

    2017-01-01

    Joint attention has been extensively studied in the developmental literature because of overwhelming evidence that the ability to socially coordinate visual attention to an object is essential to healthy developmental outcomes, including language learning. The goal of this study was to understand the complex system of sensory-motor behaviors that…

  2. Delayed early primary visual pathway development in premature infants: high density electrophysiological evidence.

    Directory of Open Access Journals (Sweden)

    Emmanuel Tremblay

    Full Text Available In the past decades, multiple studies have been interested in developmental patterns of the visual system in healthy infants. During the first year of life, differential maturational changes have been observed between the Magnocellular (P and the Parvocellular (P visual pathways. However, few studies investigated P and M system development in infants born prematurely. The aim of the present study was to characterize P and M system maturational differences between healthy preterm and fullterm infants through a critical period of visual maturation: the first year of life. Using a cross-sectional design, high-density electroencephalogram (EEG was recorded in 31 healthy preterms and 41 fullterm infants of 3, 6, or 12 months (corrected age for premature babies. Three visual stimulations varying in contrast and spatial frequency were presented to stimulate preferentially the M pathway, the P pathway, or both systems simultaneously during EEG recordings. Results from early visual evoked potentials in response to the stimulation that activates simultaneously both systems revealed longer N1 latencies and smaller P1 amplitudes in preterm infants compared to fullterms. Moreover, preterms showed longer N1 and P1 latencies in response to stimuli assessing the M pathway at 3 months. No differences between preterms and fullterms were found when using the preferential P system stimulation. In order to identify the cerebral generator of each visual response, distributed source analyses were computed in 12-month-old infants using LORETA. Source analysis demonstrated an activation of the parietal dorsal region in fullterm infants, in response to the preferential M pathway, which was not seen in the preterms. Overall, these findings suggest that the Magnocellular pathway development is affected in premature infants. Although our VEP results suggest that premature children overcome, at least partially, the visual developmental delay with time, source analyses reveal

  3. Comparison of visual and topographic outcomes of deep-anterior lamellar keratoplasty and penetrating keratoplasty in keratoconus

    Science.gov (United States)

    Yüksel, Bora; Kandemir, Baran; Uzunel, Umut Duygu; Çelik, Ozan; Ceylan, Sezgin; Küsbeci, Tuncay

    2017-01-01

    AIM To compare visual, surgical and topographic outcomes of deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) for keratoconus (KC). METHODS In this multicenter, prospective, randomized clinical trial 76 eyes of 71 KC patients operated between January 2011 and July 2014 in 2 tertiary referral hospitals were included. Consecutive patients were alternately selected to receive one of the two surgical methods. Thirty eight eyes underwent DALK with the big-bubble technique and 38 eyes underwent PK. RESULTS Mean best spectacle corrected visual acuity (BSCVA) at the first postoperative week (P=0.012) and the first postoperative month (P<0.001) was statistically significantly higher in DALK group. The mean BSCVA at 12mo was not significantly different for DALK (0.30±1.99 logMAR) versus PK (0.40±0.33 logMAR) (P=0.104). The 76.3% of the eyes had a BSCVA over 0.5 in DALK and 47.4% in PK group (P=0.009). The 7.9% of the eyes had a BSCVA of 1.0 in DALK and 5.3% in PK group (P=0.644). Mean spherical equivalent was -2.94 D in DALK and -3.09 D in PK group. Mean topographic astigmatism was 4.62 D and 4.18 D respectively. Regular topographic patterns were observed in 31 (81.6%) of DALK and 29 (76.3%) of PK (P=0.574). The most frequent topographic pattern was oblate asymmetric bow tie, seen in 39.5% in DALK and 23.7% in PK. CONCLUSION Big bubble DALK provides an earlier visual improvement compare to PK. However, visual and topographic outcomes are similar to those in PK at 1y. Postoperative complications including rejection and intraocular pressure elevation are more frequent in PK. DALK is a safer alternative to PK for KC. However, intraoperative perforation of the Descemet's membrane is a significant complication.

  4. MRI of optic nerve and postchiasmal visual pathways and visual evoked potentials in secondary progressive multiple sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Davies, M.B.; Hawkins, C.P. [School of Postgraduate Medicine, Keele Univ. (United Kingdom)]|[Department of Neurology and Neurophysiology, Royal Infirmary, Stoke-on-Trent (United Kingdom); Williams, R. [MRI Unit Cornwall House, Stoke-on-Trent (United Kingdom); Haq, N. [Department of Neurology, North Staffordshire Hospital, Stoke-on-Trent (United Kingdom); Pelosi, L. [Department of Neurology and Neurophysiology, Royal Infirmary, Stoke-on-Trent (United Kingdom)

    1998-12-01

    We studied the relationship between abnormalities shown by MRI and functional disturbances in the visual pathway as assessed by the visual evoked potential (VEP) in 25 patients with established multiple sclerosis (MS); only 4 of whom had a history of acute optic neuritis. Optic nerve MRI was abnormal in 19 (76 %) and is thus useful in detecting subclinical disease. Optic nerve total lesion length and area on the STIR sequence was found to correlate significantly with prolongation of the VEP latency. This may reflect a predominantly demyelinating rather than inflammatory origin for the signal change in the optic nerve. (orig.) With 5 figs., 1 tab., 25 refs.

  5. Visual stimulation, {sup 1}H MR spectroscopy and fMRI of the human visual pathways

    Energy Technology Data Exchange (ETDEWEB)

    Boucard, Christine C.; Cornelissen, Frans W. [University of Groningen, Laboratory for Experimental Ophthalmology, Postbus 30001, Groningen (Netherlands); University of Groningen, BCN Neuro-imaging Center, Postbus 196, Groningen (Netherlands); Mostert, Jop P.; Keyser, Jacques De [University Hospital Groningen, Department of Neurology, Groningen (Netherlands); Oudkerk, Matthijs; Sijens, Paul E. [University Hospital Groningen, Department of Radiology, Groningen (Netherlands)

    2005-01-01

    The purpose was to assess changes in lactate content and other brain metabolites under visual stimulation in optical chiasm, optic radiations and occipital cortex using multiple voxel MR spectroscopy (MRS). {sup 1}H chemical shift imaging (CSI) examinations of transverse planes centered to include the above structures were performed in four subjects at an echo time of 135 ms. Functional MRI (fMRI) was used to confirm the presence of activity in the visual cortex during the visual stimulation. Spectral maps of optical chiasm were of poor quality due to field disturbances caused by nearby large blood vessels and/or eye movements. The optic radiations and the occipital lobe did not show any significant MR spectral change upon visual stimulation, i.e., the peak areas of inositol, choline, creatine, glutamate and N-acetylaspartate were not affected. Reproducible lactate signals were not observed. fMRI confirmed the presence of strong activations in stimulated visual cortex. Prolonged visual stimulation did not cause significant changes in MR spectra. Any signal observed near the 1.33 ppm resonance frequency of the lactate methyl-group was artifactual, originating from lipid signals from outside the volume of interest (VOI). Previous claims about changes in lactate levels in the visual cortex upon visual stimulation may have been based on such erroneous observations. (orig.)

  6. User-centered evaluation of Arizona BioPathway: an information extraction, integration, and visualization system.

    Science.gov (United States)

    Quiñones, Karin D; Su, Hua; Marshall, Byron; Eggers, Shauna; Chen, Hsinchun

    2007-09-01

    Explosive growth in biomedical research has made automated information extraction, knowledge integration, and visualization increasingly important and critically needed. The Arizona BioPathway (ABP) system extracts and displays biological regulatory pathway information from the abstracts of journal articles. This study uses relations extracted from more than 200 PubMed abstracts presented in a tabular and graphical user interface with built-in search and aggregation functionality. This paper presents a task-centered assessment of the usefulness and usability of the ABP system focusing on its relation aggregation and visualization functionalities. Results suggest that our graph-based visualization is more efficient in supporting pathway analysis tasks and is perceived as more useful and easier to use as compared to a text-based literature-viewing method. Relation aggregation significantly contributes to knowledge-acquisition efficiency. Together, the graphic and tabular views in the ABP Visualizer provide a flexible and effective interface for pathway relation browsing and analysis. Our study contributes to pathway-related research and biological information extraction by assessing the value of a multiview, relation-based interface that supports user-controlled exploration of pathway information across multiple granularities.

  7. Visual pathway abnormalities were found in most multiple sclerosis patients despite history of previous optic neuritis

    Directory of Open Access Journals (Sweden)

    Stella Maris Costa Castro

    2013-07-01

    Full Text Available Objective It was to investigate visual field (VF abnormalities in a group of multiple sclerosis (MS patients in the remission phase and the presence of magnetic resonance imaging (MRI lesions in the optic radiations. Methods VF was assessed in 60 participants (age range 20-51 years: 35 relapsing-remitting MS patients [20 optic neuritis (+, 15 optic neuritis (-] and 25 controls. MRI (3-Tesla was obtained in all patients. Results Visual parameters were abnormal in MS patients as compared to controls. The majority of VF defects were diffuse. All patients except one had posterior visual pathways lesions. No significant difference in lesion number, length and distribution was noted between patients with and without history of optic neuritis. One patient presented homonymous hemianopsia. Conclusion Posterior visual pathway abnormalities were found in most MS patients despite history of previous optic neuritis.

  8. Signal Propagation in the Human Visual Pathways: An Effective Connectivity Analysis.

    Science.gov (United States)

    Youssofzadeh, Vahab; Prasad, Girijesh; Fagan, Andrew J; Reilly, Richard B; Martens, Sven; Meaney, James F; Wong-Lin, KongFatt

    2015-09-30

    Although the visual system has been extensively investigated, an integrated account of the spatiotemporal dynamics of long-range signal propagation along the human visual pathways is not completely known or validated. In this work, we used dynamic causal modeling approach to provide insights into the underlying neural circuit dynamics of pattern reversal visual-evoked potentials extracted from concurrent EEG-fMRI data. A recurrent forward-backward connectivity model, consisting of multiple interacting brain regions identified by EEG source localization aided by fMRI spatial priors, best accounted for the data dynamics. Sources were first identified in the thalamic area, primary visual cortex, as well as higher cortical areas along the ventral and dorsal visual processing streams. Consistent with hierarchical early visual processing, the model disclosed and quantified the neural temporal dynamics across the identified activity sources. This signal propagation is dominated by a feedforward process, but we also found weaker effective feedback connectivity. Using effective connectivity analysis, the optimal dynamic causal modeling revealed enhanced connectivity along the dorsal pathway but slightly suppressed connectivity along the ventral pathway. A bias was also found in favor of the right hemisphere consistent with functional attentional asymmetry. This study validates, for the first time, the long-range signal propagation timing in the human visual pathways. A similar modeling approach can potentially be used to understand other cognitive processes and dysfunctions in signal propagation in neurological and neuropsychiatric disorders. Significance statement: An integrated account of long-range visual signal propagation in the human brain is currently incomplete. Using computational neural modeling on our acquired concurrent EEG-fMRI data under a visual evoked task, we found not only a substantial forward propagation toward "higher-order" brain regions but also a

  9. Exploring visual attention functions of the human extrageniculate pathways through behavioral cues.

    Science.gov (United States)

    Mizzi, Raphaël; Michael, George A

    2016-11-01

    Over the past few decades, evidence has accumulated showing that, at subcortical levels, visual attention depends partly on the extrageniculate neural pathways, that is, those pathways that bypass the lateral geniculate nucleus and circumvent the primary visual cortex. Working in concert with neuroscience, experimental psychology has contributed considerably to the understanding of the role these pathways play through the use of 3 behavioral cues: nasal-temporal asymmetries, responses to S-cone stimuli, and responses to perceptually suppressed stimuli. In this article, after presenting the extrageniculate pathways and the role of each of the component structures in visual attention, we review findings from studies that have used these behavioral cues, as well as what they tell us about the role of the extrageniculate pathways in visual attention. We conclude that nasal-temporal asymmetries and responses to S-cone stimuli are plausible probes of extrageniculate functions, because they are consistent with neurophysiological, neuropsychological, and neuroimaging findings. By contrast, despite promising perspectives, the literature is yet too scarce for responses to perceptually suppressed stimuli to be considered as a plausible probe of extrageniculate-dependent attention functions. (PsycINFO Database Record

  10. PathwayExplorer: web service for visualizing high-throughput expression data on biological pathways.

    Science.gov (United States)

    Mlecnik, Bernhard; Scheideler, Marcel; Hackl, Hubert; Hartler, Jürgen; Sanchez-Cabo, Fatima; Trajanoski, Zlatko

    2005-07-01

    While generation of high-throughput expression data is becoming routine, the fast, easy, and systematic presentation and analysis of these data in a biological context is still an obstacle. To address this need, we have developed PathwayExplorer, which maps expression profiles of genes or proteins simultaneously onto major, currently available regulatory, metabolic and cellular pathways from KEGG, BioCarta and GenMAPP. PathwayExplorer is a platform-independent web server application with an optional standalone Java application using a SOAP (simple object access protocol) interface. Mapped pathways are ranked for the easy selection of the pathway of interest, displaying all available genes of this pathway with their expression profiles in a selectable and intuitive color code. Pathway maps produced can be downloaded as PNG, JPG or as high-resolution vector graphics SVG. The web service is freely available at https://pathwayexplorer.genome.tugraz.at; the standalone client can be downloaded at http://genome.tugraz.at.

  11. Striatal direct pathway modulates response time in execution of visual discrimination.

    Science.gov (United States)

    Fukabori, Ryoji; Okada, Kana; Nishizawa, Kayo; Kai, Nobuyuki; Kobayashi, Kenta; Uchigashima, Motokazu; Watanabe, Masahiko; Tsutsui, Yuji; Kobayashi, Kazuto

    2012-03-01

    The dorsal striatum in the basal ganglia circuitry is a principal structure that mediates the acquisition and performance of instrumental learning. The projections from the dorsal striatum are composed of two subpopulations of medium spiny neurons that constitute the direct and indirect pathways. The mechanism by which these striatal projections control the learning processes of instrumental actions remains unknown. We addressed the behavioral role of the striatal direct (striatonigral) pathway in the performance of visual discrimination. Immunotoxin targeting of the striatal neuronal type containing dopamine D(1) receptor in mice resulted in a moderate level of elimination of the striatonigral pathway. Targeting of the neural pathway from the whole region of the dorsal striatum lengthened the response time but did not affect the accuracy of response selection in a two-choice reaction time task dependent on light stimulus. This lengthened motor response was induced early in the test sessions and was gradually restored to normal levels during repetitive sessions. In addition, subregion-specific pathway targeting revealed that the delay in learned motor response was generated by the elimination of the striatonigral pathway arising from the dorsomedial striatum but not from the dorsolateral striatum. Our findings indicate that the striatonigral pathway, in particular from the dorsomedial striatum, contributes to the regulation of response time in the execution of visual discrimination. The restoration of motor response deficits during repetitive sessions suggests the presence of a mechanism by which the response facilitation is acquired through continuation of learning despite the removal of the striatonigral pathway.

  12. Amplified somatosensory and visual cortical projections to a core auditory area, the anterior auditory field, following early- and late-onset deafness.

    Science.gov (United States)

    Wong, Carmen; Chabot, Nicole; Kok, Melanie A; Lomber, Stephen G

    2015-09-01

    Cross-modal reorganization following the loss of input from a sensory modality can recruit sensory-deprived cortical areas to process information from the remaining senses. Specifically, in early-deaf cats, the anterior auditory field (AAF) is unresponsive to auditory stimuli but can be activated by somatosensory and visual stimuli. Similarly, AAF neurons respond to tactile input in adult-deafened animals. To examine anatomical changes that may underlie this functional adaptation following early or late deafness, afferent projections to AAF were examined in hearing cats, and cats with early- or adult-onset deafness. Unilateral deposits of biotinylated dextran amine were made in AAF to retrogradely label cortical and thalamic afferents to AAF. In early-deaf cats, ipsilateral neuronal labeling in visual and somatosensory cortices increased by 329% and 101%, respectively. The largest increases arose from the anterior ectosylvian visual area and the anterolateral lateral suprasylvian visual area, as well as somatosensory areas S2 and S4. Consequently, labeling in auditory areas was reduced by 36%. The age of deafness onset appeared to influence afferent connectivity, with less marked differences observed in late-deaf cats. Profound changes to visual and somatosensory afferent connectivity following deafness may reflect corticocortical rewiring affording acoustically deprived AAF with cross-modal functionality.

  13. A Major Human White Matter Pathway Between Dorsal and Ventral Visual Cortex.

    Science.gov (United States)

    Takemura, Hiromasa; Rokem, Ariel; Winawer, Jonathan; Yeatman, Jason D; Wandell, Brian A; Pestilli, Franco

    2016-05-01

    Human visual cortex comprises many visual field maps organized into clusters. A standard organization separates visual maps into 2 distinct clusters within ventral and dorsal cortex. We combined fMRI, diffusion MRI, and fiber tractography to identify a major white matter pathway, the vertical occipital fasciculus (VOF), connecting maps within the dorsal and ventral visual cortex. We use a model-based method to assess the statistical evidence supporting several aspects of the VOF wiring pattern. There is strong evidence supporting the hypothesis that dorsal and ventral visual maps communicate through the VOF. The cortical projection zones of the VOF suggest that human ventral (hV4/VO-1) and dorsal (V3A/B) maps exchange substantial information. The VOF appears to be crucial for transmitting signals between regions that encode object properties including form, identity, and color and regions that map spatial information.

  14. Posterior septal and right free-wall Kent pathways visualized in situ and removed at operation.

    Science.gov (United States)

    Brodman, R F; Fisher, J D; Mitsudo, S; Kim, S G; Mercando, A; Ferrick, K; Furman, S

    1989-09-01

    This article describes the first posterior septal and first and second right free-wall pathways identified at operation for Wolff-Parkinson-White syndrome and confirmed histologically. All pathways were found in the areas of preexcitation identified by pre and intraoperative mapping. They bridged the atrium and ventricle, and postoperative electrophysiological testing confirmed division of the pathways. Kent bundles may be identified at the time of surgery but they appear to be gossamer structures usually destroyed during surgical manipulation of the coronary sulcus. Visualization of the suspected bypass tract should not alter or limit the extent of surgical dissection.

  15. Parvocellular Pathway Impairment in Autism Spectrum Disorder: Evidence from Visual Evoked Potentials

    Science.gov (United States)

    Fujita, Takako; Yamasaki, Takao; Kamio, Yoko; Hirose, Shinichi; Tobimatsu, Shozo

    2011-01-01

    In humans, visual information is processed via parallel channels: the parvocellular (P) pathway analyzes color and form information, whereas the magnocellular (M) stream plays an important role in motion analysis. Individuals with autism spectrum disorder (ASD) often show superior performance in processing fine detail, but impaired performance in…

  16. Magnetic resonance imaging of the visual pathway - anatomical and technical considerations; Obrazowanie drogi wzrokowej metoda rezonansu magnetycznego - anatomia, technika badania

    Energy Technology Data Exchange (ETDEWEB)

    Sosnowski, P.; Paprzycki, W. [Akademia Medyczna, Poznan (Poland)

    1993-12-31

    Magnetic resonance tomography creates possibility of imaging the whole visual pathway and is superior to CT. Plenitude of MR techniques can sometimes be the reason of unnecessary prolongation of the examination. This study tries to evaluate usefulness of different MR techniques and planes for optimal imaging of consecutive sections of visual pathway. (author). 7 refs, 6 figs.

  17. A visual pathway links brain structures active during magnetic compass orientation in migratory birds.

    Directory of Open Access Journals (Sweden)

    Dominik Heyers

    Full Text Available The magnetic compass of migratory birds has been suggested to be light-dependent. Retinal cryptochrome-expressing neurons and a forebrain region, "Cluster N", show high neuronal activity when night-migratory songbirds perform magnetic compass orientation. By combining neuronal tracing with behavioral experiments leading to sensory-driven gene expression of the neuronal activity marker ZENK during magnetic compass orientation, we demonstrate a functional neuronal connection between the retinal neurons and Cluster N via the visual thalamus. Thus, the two areas of the central nervous system being most active during magnetic compass orientation are part of an ascending visual processing stream, the thalamofugal pathway. Furthermore, Cluster N seems to be a specialized part of the visual wulst. These findings strongly support the hypothesis that migratory birds use their visual system to perceive the reference compass direction of the geomagnetic field and that migratory birds "see" the reference compass direction provided by the geomagnetic field.

  18. A visual pathway links brain structures active during magnetic compass orientation in migratory birds.

    Science.gov (United States)

    Heyers, Dominik; Manns, Martina; Luksch, Harald; Güntürkün, Onur; Mouritsen, Henrik

    2007-09-26

    The magnetic compass of migratory birds has been suggested to be light-dependent. Retinal cryptochrome-expressing neurons and a forebrain region, "Cluster N", show high neuronal activity when night-migratory songbirds perform magnetic compass orientation. By combining neuronal tracing with behavioral experiments leading to sensory-driven gene expression of the neuronal activity marker ZENK during magnetic compass orientation, we demonstrate a functional neuronal connection between the retinal neurons and Cluster N via the visual thalamus. Thus, the two areas of the central nervous system being most active during magnetic compass orientation are part of an ascending visual processing stream, the thalamofugal pathway. Furthermore, Cluster N seems to be a specialized part of the visual wulst. These findings strongly support the hypothesis that migratory birds use their visual system to perceive the reference compass direction of the geomagnetic field and that migratory birds "see" the reference compass direction provided by the geomagnetic field.

  19. HPIminer: A text mining system for building and visualizing human protein interaction networks and pathways.

    Science.gov (United States)

    Subramani, Suresh; Kalpana, Raja; Monickaraj, Pankaj Moses; Natarajan, Jeyakumar

    2015-04-01

    The knowledge on protein-protein interactions (PPI) and their related pathways are equally important to understand the biological functions of the living cell. Such information on human proteins is highly desirable to understand the mechanism of several diseases such as cancer, diabetes, and Alzheimer's disease. Because much of that information is buried in biomedical literature, an automated text mining system for visualizing human PPI and pathways is highly desirable. In this paper, we present HPIminer, a text mining system for visualizing human protein interactions and pathways from biomedical literature. HPIminer extracts human PPI information and PPI pairs from biomedical literature, and visualize their associated interactions, networks and pathways using two curated databases HPRD and KEGG. To our knowledge, HPIminer is the first system to build interaction networks from literature as well as curated databases. Further, the new interactions mined only from literature and not reported earlier in databases are highlighted as new. A comparative study with other similar tools shows that the resultant network is more informative and provides additional information on interacting proteins and their associated networks.

  20. The role of the collicular pathway in the salience-based progression of visual attention.

    Science.gov (United States)

    Mizzi, Raphaël; Michael, George A

    2014-08-15

    Visual attention has been shown to progress from the most to the least salient item in a given scene. Cognitive and physiological models assume that this orienting of covert attention relies on the collicular pathway, involving the superior colliculus and the pulvinar. Recent studies questioned this statement as they described attentional capture by visual items invisible to the superior colliculus. Electrophysiological studies shown that there is no direct projections from short-wave receptors to the superior colliculus. S-cone stimuli can thus be employed to assess visual processing without the involvement of the collicular pathway. We have attempted to investigate whether this pathway is involved in the salience-based orientation of attention by presenting S-cone stimuli. Volunteers were asked to make a judgment regarding a target among two distractors (all items of unequal sizes). Items' location and size varied randomly, as well as color, randomly black or calibrated for each subject to activate exclusively S-cones. The hierarchical pattern testifying of the salience-based orientation of attention was only found with black stimuli, arguing in favor of an implication of the collicular pathway in salience. In a second experiment, one item was presented at a time in order to test the item-multiplicity effect by comparing experiments. Performance was the most penalized when presenting multiple stimuli in the black condition. Results were interpreted in terms of distinct modes of processing by the collicular and geniculate pathways. The establishment of salience that determines attentional progression appeared to be only possible when the collicular pathway was solicited.

  1. Visinets: a web-based pathway modeling and dynamic visualization tool.

    Directory of Open Access Journals (Sweden)

    Jozef Spychala

    Full Text Available In this report we describe a novel graphically oriented method for pathway modeling and a software package that allows for both modeling and visualization of biological networks in a user-friendly format. The Visinets mathematical approach is based on causal mapping (CMAP that has been fully integrated with graphical interface. Such integration allows for fully graphical and interactive process of modeling, from building the network to simulation of the finished model. To test the performance of Visinets software we have applied it to: a create executable EGFR-MAPK pathway model using an intuitive graphical way of modeling based on biological data, and b translate existing ordinary differential equation (ODE based insulin signaling model into CMAP formalism and compare the results. Our testing fully confirmed the potential of the CMAP method for broad application for pathway modeling and visualization and, additionally, showed significant advantage in computational efficiency. Furthermore, we showed that Visinets web-based graphical platform, along with standardized method of pathway analysis, may offer a novel and attractive alternative for dynamic simulation in real time for broader use in biomedical research. Since Visinets uses graphical elements with mathematical formulas hidden from the users, we believe that this tool may be particularly suited for those who are new to pathway modeling and without the in-depth modeling skills often required when using other software packages.

  2. PANDA: pathway and annotation explorer for visualizing and interpreting gene-centric data.

    Science.gov (United States)

    Hart, Steven N; Moore, Raymond M; Zimmermann, Michael T; Oliver, Gavin R; Egan, Jan B; Bryce, Alan H; Kocher, Jean-Pierre A

    2015-01-01

    Objective. Bringing together genomics, transcriptomics, proteomics, and other -omics technologies is an important step towards developing highly personalized medicine. However, instrumentation has advances far beyond expectations and now we are able to generate data faster than it can be interpreted. Materials and Methods. We have developed PANDA (Pathway AND Annotation) Explorer, a visualization tool that integrates gene-level annotation in the context of biological pathways to help interpret complex data from disparate sources. PANDA is a web-based application that displays data in the context of well-studied pathways like KEGG, BioCarta, and PharmGKB. PANDA represents data/annotations as icons in the graph while maintaining the other data elements (i.e., other columns for the table of annotations). Custom pathways from underrepresented diseases can be imported when existing data sources are inadequate. PANDA also allows sharing annotations among collaborators. Results. In our first use case, we show how easy it is to view supplemental data from a manuscript in the context of a user's own data. Another use-case is provided describing how PANDA was leveraged to design a treatment strategy from the somatic variants found in the tumor of a patient with metastatic sarcomatoid renal cell carcinoma. Conclusion. PANDA facilitates the interpretation of gene-centric annotations by visually integrating this information with context of biological pathways. The application can be downloaded or used directly from our website: http://bioinformaticstools.mayo.edu/research/panda-viewer/.

  3. PANDA: pathway and annotation explorer for visualizing and interpreting gene-centric data

    Directory of Open Access Journals (Sweden)

    Steven N. Hart

    2015-05-01

    Full Text Available Objective. Bringing together genomics, transcriptomics, proteomics, and other -omics technologies is an important step towards developing highly personalized medicine. However, instrumentation has advances far beyond expectations and now we are able to generate data faster than it can be interpreted. Materials and Methods. We have developed PANDA (Pathway AND Annotation Explorer, a visualization tool that integrates gene-level annotation in the context of biological pathways to help interpret complex data from disparate sources. PANDA is a web-based application that displays data in the context of well-studied pathways like KEGG, BioCarta, and PharmGKB. PANDA represents data/annotations as icons in the graph while maintaining the other data elements (i.e., other columns for the table of annotations. Custom pathways from underrepresented diseases can be imported when existing data sources are inadequate. PANDA also allows sharing annotations among collaborators. Results. In our first use case, we show how easy it is to view supplemental data from a manuscript in the context of a user’s own data. Another use-case is provided describing how PANDA was leveraged to design a treatment strategy from the somatic variants found in the tumor of a patient with metastatic sarcomatoid renal cell carcinoma. Conclusion. PANDA facilitates the interpretation of gene-centric annotations by visually integrating this information with context of biological pathways. The application can be downloaded or used directly from our website: http://bioinformaticstools.mayo.edu/research/panda-viewer/.

  4. Progress in visual processing pathways in compound eyes of bees%蜜蜂复眼的视觉通路研究进展

    Institute of Scientific and Technical Information of China (English)

    赵慧霞; 郑火青; 胡福良

    2012-01-01

    视觉通路的研究在神经科学、仿生应用和医学治疗上都具有十分重要的意义.西方蜜蜂Apis mellifera作为神经生物学研究的重要模式生物已被广泛地应用于视觉通路的研究.蜜蜂的视觉器官包括1对复眼和3只单眼,复眼是形成视觉的主要感觉器官.视叶是蜜蜂传递和处理视觉信息的主要神经构造,它包括视神经节层、视髓质层、视小叶和前视结节4个等级的神经纤维网.复杂的视觉信息在经过大脑的各级神经时被分离,以许多空间隔离的并行连续的视觉通路传递和加工,然后汇集到高级脑中枢,部分甚至与其他感觉模态的信息相整合,最终输出有效信息来调控蜜蜂的各种行为.本文按照信息在视叶中逐级传递的顺序对蜜蜂复眼的视觉通路研究进展进行综述.%Research on the visual processing pathways is of great significance in neuroscience, bionic applications and medical treatments. The western honeybee, Apis mellifera, as an important model organism for neurobiology research, has been extensively applied to the research on visual processing pathways. The visual organs of bees include a pair of compound eyes and three ocelli, in which the compound eyes are most important for vision formation. In bees, processing of visual information is achieved within the optic lobes which are divided into four levels of neuropils, i. e., lamina, medulla, lobula and anterior optic tubercle. Complex visual information is segregated at successive stages within the brain, and processed in many parallel and sequential visual pathways. Then they are converged in higher-order brain centers, with some integrated with information of other modalities, which finally generate effective outputs to regulate and control bee behaviours. In this article, the research on visual processing pathways in bee compound eyes is reviewed according to the sequence of information processing in the optic lobes.

  5. Design of a Novel Servo-motorized Laser Device for Visual Pathways Diseases Therapy

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    Carlos Ignacio Sarmiento

    2015-12-01

    Full Text Available We discuss a novel servo-motorized laser device and a research protocol for visual pathways diseases therapies. The proposed servo-mechanized laser device can be used for potential rehabilitation of patients with hemianopia, quadrantanopia, scotoma, and some types of cortical damages. The device uses a semi spherical structure where the visual stimulus will be shown inside, according to a previous stimuli therapy designed by an ophthalmologist or neurologist. The device uses a pair of servomotors (with torque=1.5kg, which controls the laser stimuli position for the internal therapy and another pair for external therapy. Using electronic tools such as microcontrollers along with miscellaneous electronic materials, combined with LabVIEW based interface, a control mechanism is developed for the new device. The proposed device is well suited to run various visual stimuli therapies. We outline the major design principles including the physical dimensions, laser device’s kinematical analysis and the corresponding software development.

  6. Viral vector-mediated selective and reversible blockade of the pathway for visual orienting in mice

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    Tadashi eIsa

    2013-10-01

    Full Text Available Recently, by using a combination of two viral vectors, we developed a technique for pathway-selective and reversible synaptic transmission blockade, and successfully induced a behavioral deficit of dexterous hand movements in macaque monkeys by affecting a population of spinal interneurons. To explore the capacity of this technique to work in other pathways and species, and to obtain fundamental methodological information, we tried to block the crossed tecto-reticular pathway, which is known to control orienting responses to visual targets, in mice. A neuron-specific retrograde gene transfer vector with the gene encoding enhanced tetanus neurotoxin (eTeNT tagged with enhanced green fluorescent protein (EGFP under the control of a tetracycline responsive element was injected into the left medial pontine reticular formation. 7–17 days later, an adeno-associated viral vector with a highly efficient Tet-ON sequence, rtTAV16, was injected into the right superior colliculus. 5–9 weeks later, the daily administration of doxycycline (Dox was initiated. Visual orienting responses toward the left side were impaired 1 - 4 days after Dox administration. Anti-GFP immunohistochemistry revealed that a number of neurons in the intermediate and deep layers of the right superior colliculus were positively stained, indicating eTeNT expression. After the termination of Dox administration, the anti-GFP staining returned to the baseline level within 28 days. A second round of Dox administration, starting from 28 days after the termination of the first Dox administration, resulted in the reappearance of the behavioral impairment. These findings showed that pathway-selective and reversible blockade of synaptic transmission causes behavioral effects also in rodents, and that the crossed tecto-reticular pathway surely controls visual orienting behaviors.

  7. A new study on diffusion tensor imaging of the whole visual pathway fiber bundle and clinical application

    Institute of Scientific and Technical Information of China (English)

    TAO Xiao-feng; WANG Zhong-qiu; GONG Wan-qing; JIANG Qing-jun; SHI Zeng-ru

    2009-01-01

    Background With conventional imaging methods only the morphous of the visual nerve fiber bundles can be demonstrated, while the earlier period functional changes can not be demonstrated. We hypothesized that diffusion tensor imaging (DTI) would demonstrated the whole optic never fiber bundle and visual pathway and the earlier period functional changes. The purpose of the present study was to evaluate the application of DTI technique in the demonstration of the whole optic never fiber bundle and visual pathway, and the influence of orbital tumors on them. Methods GE 1.5T signa HD MR System, and the software package DTV2 were adopted. The total 45 subjects were enrolled, including 15 volunteers and 30 patients. All patients had ocular proptosis from minor to major. Seven patients had visual acuity decrescence. Results The nerve fiber bundles, e.g. optic chiasma, optic tract and optic radiation in posterior visual pathway were well demonstrated in all cases. Wherein, the intact whole visual pathway fiber bundles were clearly revealed in 10 volunteers and 17 patients, and optic nerve was not wholly revealed in the rest of the subjects. Shift of optic nerve caused by compression and partial deformation were seen in 7 patients with orbital tumor. In 6 of 7 patients, DTI displayed significant abscise and deformation of visual nerve. Chi-square test indicated significant correlation between visual acuity decrescence and DTI visual nerve non-display. Conclusions Visual nerve fiber bundles and the whole visual pathway were visualized in most of patients with DTI. It might be an effective method of providing imaging evidence for visual nerve fiber earlier period functional changes, and laid a foundation for the study in other cranial nerves.

  8. Arc visualization of odor objects reveals experience-dependent ensemble sharpening, separation, and merging in anterior piriform cortex in adult rat.

    Science.gov (United States)

    Shakhawat, Amin Md; Harley, Carolyn W; Yuan, Qi

    2014-07-30

    Visualization using the immediate early gene Arc revealed sparser and more robust odor representations in the anterior piriform cortex of adult rats when odor was associated with water reward over 2-3 d. Rewarded odor "mixtures" resulted in rats responding to either component odor similarly, and, correspondingly, the odor representations became more similar as indexed by increased overlap in piriform Arc-expressing (Arc(+)) pyramidal neurons. The increased overlap was consistent with the rats' generalization from component odors. Discriminating among highly similar odor mixtures for reward led to increased differentiation of the neural representations as indexed by a reduction in overlap for piriform Arc(+) pyramidal neurons after training. Similar odor mixture discrimination also required more trials to criterion. The visible reduction in the overlap of odor representations indexes pattern separation. The Arc visualization of odor representations in the anterior piriform network suggests that odor objects are widely distributed representations and can be rapidly modified by reward training in adult rats. We suggest that dynamic changes such as those observed here in piriform odor encoding are at the heart of perceptual learning and reflect the continuing plastic nature of mature associative cortex as an outcome of successful problem solving.

  9. ArrayXPath: mapping and visualizing microarray gene-expression data with integrated biological pathway resources using Scalable Vector Graphics.

    Science.gov (United States)

    Chung, Hee-Joon; Kim, Mingoo; Park, Chan Hee; Kim, Jihoon; Kim, Ju Han

    2004-07-01

    Biological pathways can provide key information on the organization of biological systems. ArrayXPath (http://www.snubi.org/software/ArrayXPath/) is a web-based service for mapping and visualizing microarray gene-expression data for integrated biological pathway resources using Scalable Vector Graphics (SVG). By integrating major bio-databases and searching pathway resources, ArrayXPath automatically maps different types of identifiers from microarray probes and pathway elements. When one inputs gene-expression clusters, ArrayXPath produces a list of the best matching pathways for each cluster. We applied Fisher's exact test and the false discovery rate (FDR) to evaluate the statistical significance of the association between a cluster and a pathway while correcting the multiple-comparison problem. ArrayXPath produces Javascript-enabled SVGs for web-enabled interactive visualization of pathways integrated with gene-expression profiles.

  10. Fourier transformed steady-state flash evoked potentials for continuous monitoring of visual pathway function.

    Science.gov (United States)

    Bergholz, R; Lehmann, T N; Fritz, G; Rüther, K

    2008-05-01

    Monitoring of somatosensory, motor and auditory pathway function by evoked potentials is routine in surgery placing these pathways at risk. However, visual pathway function remains yet inaccessible to a reliable monitoring. For this study, a method of continuous recordings was developed and tested. Steady-state visual evoked potentials were elicited by flash stimulation at 16 Hz and analysed using discrete Fourier transform. Amplitude and phase of the fundamental response were dynamically averaged and continuously plotted in a trend graph. The method was applied on awake individuals with normal vision and on patients undergoing neurosurgery. In most individuals it was possible to continuously record significant responses. Surprisingly, characteristic time-courses of amplitude and phase were observed in several subjects. These findings were attributed mainly to flicker-adaptation. During anesthesia, amplitude and signal-to-noise ratio were markedly smaller. Signal recognition was facilitated when potentials were recorded with a subdural electrode placed directly at the occipital pole. The anesthetic agent propofol had a major impact on the recordings.

  11. Optical coherence tomography and electrophysiology of retinal and visual pathways in Wilson's disease.

    Science.gov (United States)

    Langwińska-Wośko, Ewa; Litwin, Tomasz; Szulborski, Kamil; Członkowska, Anna

    2016-04-01

    We evaluated correlations between positive findings of changes on brain magnetic resonance imaging (MRI) and selected morphological and electrophysiological parameters of the retinal and visual systems in Wilson's disease. Fifty-eight Wilson's disease symptomatic patients were divided according to whether they displayed brain changes on MRI (positive, n = 39; negative, n = 19). All participants and healthy control group (n = 30), underwent retinal optical coherence tomography to assess the thickness of macula and the total retinal nerve fiber layer. Visual evoked potentials were measured and electroretinography was performed. Macular and retinal nerve fibers were thinner in participants with changes on MRI than in participants without changes. Electrophysiological parameters were markedly different in the MRI positive group compared with the negative group and 30 healthy controls; however, some abnormalities were evident in cases without visible brain pathology. Morphological and electrophysiological changes of retinal and visual pathways are associated with MRI visualized brain injury in Wilson's disease and may be useful for detecting the degree of neurodegeneration.

  12. Functional MRI Examination of Visual Pathways in Patients with Unilateral Optic Neuritis

    Directory of Open Access Journals (Sweden)

    Giulia Mascioli

    2012-01-01

    Full Text Available The relations between brain areas involved in vision were explored in 8 patients with unilateral acute optic neuritis using functional magnetic resonance imaging (fMRI and diffusion tensor imaging (DTI. In all patients monocular stimulation of affected and unaffected eye elicited significantly different activation foci in the primary visual cortex (V1, whereas the foci evoked in the middle temporal visual area (area V5 were similar in size and in delay of blood-oxygen-level-dependent response. DTI analysis documented lower white matter anisotropy values and reduced fibre reconstruction in the affected compared with the unaffected optic nerves. The preserved activation of area V5 observed in all our patients is an interesting finding that suggests the notion of a different sensitivity of the optic pathways to inflammatory changes.

  13. Fast and automatic activation of an abstract representation of money in the human ventral visual pathway.

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    Catherine Tallon-Baudry

    Full Text Available Money, when used as an incentive, activates the same neural circuits as rewards associated with physiological needs. However, unlike physiological rewards, monetary stimuli are cultural artifacts: how are monetary stimuli identified in the first place? How and when does the brain identify a valid coin, i.e. a disc of metal that is, by social agreement, endowed with monetary properties? We took advantage of the changes in the Euro area in 2002 to compare neural responses to valid coins (Euros, Australian Dollars with neural responses to invalid coins that have lost all monetary properties (French Francs, Finnish Marks. We show in magneto-encephalographic recordings, that the ventral visual pathway automatically distinguishes between valid and invalid coins, within only ∼150 ms. This automatic categorization operates as well on coins subjects were familiar with as on unfamiliar coins. No difference between neural responses to scrambled controls could be detected. These results could suggest the existence of a generic, all-purpose neural representation of money that is independent of experience. This finding is reminiscent of a central assumption in economics, money fungibility, or the fact that a unit of money is substitutable to another. From a neural point of view, our findings may indicate that the ventral visual pathway, a system previously thought to analyze visual features such as shape or color and to be influenced by daily experience, could also able to use conceptual attributes such as monetary validity to categorize familiar as well as unfamiliar visual objects. The symbolic abilities of the posterior fusiform region suggested here could constitute an efficient neural substrate to deal with culturally defined symbols, independently of experience, which probably fostered money's cultural emergence and success.

  14. Parallel neural pathways in higher visual centers of the Drosophila brain that mediate wavelength-specific behavior

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    Hideo eOtsuna

    2014-02-01

    Full Text Available Compared with connections between the retinae and primary visual centers, relatively less is known in both mammals and insects about the functional segregation of neural pathways connecting primary and higher centers of the visual processing cascade. Here, using the Drosophila visual system as a model, we demonstrate two levels of parallel computation in the pathways that connect primary visual centers of the optic lobe to computational circuits embedded within deeper centers in the central brain. We show that a seemingly simple achromatic behavior, namely phototaxis, is under the control of several independent pathways, each of which is responsible for navigation towards unique wavelengths. Silencing just one pathway is enough to disturb phototaxis towards one characteristic monochromatic source, whereas phototactic behavior towards white light is not affected. The response spectrum of each demonstrable pathway is different from that of individual photoreceptors, suggesting subtractive computations. A choice assay between two colors showed that these pathways are responsible for navigation towards, but not for the detection itself of, the monochromatic light. The present study provides novel insights about how visual information is separated and processed in parallel to achieve robust control of an innate behavior.

  15. Nitric oxide-sensitive guanylyl cyclase is differentially regulated by nuclear and non-nuclear estrogen pathways in anterior pituitary gland.

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    Jimena P Cabilla

    Full Text Available 17β-estradiol (E2 regulates hormonal release as well as proliferation and cell death in the pituitary. The main nitric oxide receptor, nitric oxide sensitive- or soluble guanylyl cyclase (sGC, is a heterodimer composed of two subunits, α and β, that catalyses cGMP formation. α1β1 is the most abundant and widely expressed heterodimer, showing the greater activity. Previously we have shown that E2 decreased sGC activity but exerts opposite effects on sGC subunits increasing α1 and decreasing β1 mRNA and protein levels. In the present work we investigate the mechanisms by which E2 differentially regulates sGC subunits' expression on rat anterior pituitary gland. Experiments were performed on primary cultures of anterior pituitary cells from adult female Wistar rats at random stages of estrous cycle. After 6 h of E2 treatment, α1 mRNA and protein expression is increased while β1 levels are down-regulated. E2 effects on sGC expression are partially dependent on de novo transcription while de novo translation is fully required. E2 treatment decreased HuR mRNA stabilization factor and increased AUF1 p37 mRNA destabilization factor. E2-elicited β1 mRNA decrease correlates with a mRNA destabilization environment in the anterior pituitary gland. On the other hand, after 6 h of treatment, E2-BSA (1 nM and E2-dendrimer conjugate (EDC, 1 nM were unable to modify α1 or β1 mRNA levels, showing that nuclear receptor is involved in E2 actions. However, at earlier times (3 h, 1 nM EDC causes a transient decrease of α1 in a PI3k-dependent fashion. Our results show for the first time that E2 is able to exert opposite actions in the anterior pituitary gland, depending on the activation of classical or non-classical pathways. Thus, E2 can also modify sGC expression through membrane-initiated signals bringing to light a new point of regulation in NO/sGC pathway.

  16. Visualizing water-conduction pathways of living trees: selection of dyes and tissue preparation methods.

    Science.gov (United States)

    Sano, Yuzou; Okamura, Yasuko; Utsumi, Yasuhiro

    2005-03-01

    To visualize water-conduction pathways in living trees, we introduced aqueous solutions of safranin and acid fuchsin into stems of Populus sieboldii Miquel. To examine the spread of each dye in the trees, we compared several techniques for preparing tissue for light microscopy. Acid fuchsin was distributed more rapidly and more widely than safranin, reflecting differences between the dye molecules in state of ionization. We prepared some sections without allowing the dye to redissolve after it had been stabilized by freeze-drying. In these sections, the dye was observed in vessels and in some of the adjacent ray parenchyma cells. Other sections were prepared without stabilizing the dye. In these sections, acid fuchsin in the sap stream left cell walls unstained, whereas safranin stained wood fibers in the vicinity of vessels, as well as the vessels themselves, provided that the sections were mounted in glycerin, which dissolves safranin. Although stained with safranin, the wood fibers contained no water. The results indicate that stabilization of the introduced dye and subsequent preparation of tissues under conditions that avoid dye resolublilization allow accurate visualization of water-conduction pathways at the cellular level.

  17. Cervicoplastia anterior Anterior cervicoplasty

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    Lucas Gomes Patrocínio

    2004-10-01

    Full Text Available Muitos pacientes buscam correção estética da frouxidão da pele do pescoço, depósito de gordura na região submentoneana ou bandas de platisma. Em grande parte dos casos a ação medial, via cervicoplastia anterior é necessária. OBJETIVO: Demonstrar a casuística e avaliar os resultados e complicações com a técnica de cervicoplastia anterior no Serviço de Otorrinolaringologia da Universidade Federal de Uberlândia. FORMA DE ESTUDO: Relato de série. PACIENTES E MÉTODOS: Quarenta e dois pacientes, entre 39 e 65 anos de idade, sendo 40 (95,2% do sexo feminino e 2 (4,8% do masculino, foram submetidos a cervicoplastia anterior. Retrospectivamente foram avaliados resultados e complicações. RESULTADOS: Destes, 34 apresentaram resultados satisfatórios, 4 apresentaram déficit estético notado somente pelo cirurgião, 3 apresentaram déficit estético notado somente pelo paciente e 1 apresentou déficit estético necessitando cirurgia revisional. Ao estudo fotográfico, todos os pacientes apresentaram melhora do perfil cervical, redução das bandas de platisma e da frouxidão da pele, estabilização da musculatura cervical e acentuação do ângulo cervicomental, em graus variados. Houve complicação em 2 casos (discreto serohematoma e cicatriz um pouco alargada. CONCLUSÃO: A cervicoplastia, associada ou não à tração lateral pela ritidoplastia, é uma técnica que produz resultados satisfatórios na grande maioria dos casos.Many patients look for aesthetic correction of the laxity of neck skin, submandibular fat deposit or platisma bands. In a large part of the cases, medial action, through anterior cervicoplasty is necessary. AIM: To demonstrate the casuistic and to evaluate the results and complications with anterior cervicoplasty technique in the Otorhinolaryngology Service of the Federal University of Uberlândia. STUDY DESIGN: Serie report. PATIENTS AND METHODS: Forty-two patients, between 39 and 65 years of age, being 40 (95

  18. Representation of Gravity-Aligned Scene Structure in Ventral Pathway Visual Cortex.

    Science.gov (United States)

    Vaziri, Siavash; Connor, Charles E

    2016-03-21

    The ventral visual pathway in humans and non-human primates is known to represent object information, including shape and identity [1]. Here, we show the ventral pathway also represents scene structure aligned with the gravitational reference frame in which objects move and interact. We analyzed shape tuning of recently described macaque monkey ventral pathway neurons that prefer scene-like stimuli to objects [2]. Individual neurons did not respond to a single shape class, but to a variety of scene elements that are typically aligned with gravity: large planes in the orientation range of ground surfaces under natural viewing conditions, planes in the orientation range of ceilings, and extended convex and concave edges in the orientation range of wall/floor/ceiling junctions. For a given neuron, these elements tended to share a common alignment in eye-centered coordinates. Thus, each neuron integrated information about multiple gravity-aligned structures as they would be seen from a specific eye and head orientation. This eclectic coding strategy provides only ambiguous information about individual structures but explicit information about the environmental reference frame and the orientation of gravity in egocentric coordinates. In the ventral pathway, this could support perceiving and/or predicting physical events involving objects subject to gravity, recognizing object attributes like animacy based on movement not caused by gravity, and/or stabilizing perception of the world against changes in head orientation [3-5]. Our results, like the recent discovery of object weight representation [6], imply that the ventral pathway is involved not just in recognition, but also in physical understanding of objects and scenes.

  19. Visualization

    OpenAIRE

    Balon, Andreja

    1990-01-01

    The present thesis entails the field of visualization which is divided into visualization along traditional lines and visualization in computer science. As the psychological aspect of image is of vital importance for visualization, it is shortly described in the beginning. Visualization in computer science is divided into three main fields: scientific visualization, program visualization and visual programming. An explanation and examples of approach to applications are given for each field....

  20. Dose response and time course of manganese-enhanced magnetic resonance imaging for visual pathway tracing in vivo

    Institute of Scientific and Technical Information of China (English)

    Wei-ling Wang; Hui Xu; Ying Li; Zhi-zhong Ma; Xiao-dong Sun; Yun-tao Hu

    2016-01-01

    Axonal tracing is useful for detecting optic nerve injury and regeneration, but many commonly used methods cannot be used to observe axoplasmic lfow and synaptic transmission in vivo. Manganese (Mn2+)-enhanced magnetic resonance imaging (MEMRI) can be used for in vivo longitudinal tracing of the visual pathway. Here, we explored the dose response and time course of an intravitreal injection of MnCl2 for tracing the visual pathway in rabbits in vivo using MEMRI. We found that 2 mM MnCl2 enhanced images of the optic nerve but not the lateral geniculate body or superior colliculus, whereas at all other doses tested (5–40 mM), images of the visual pathway from the retina to the contralateral superior colliculus were signiifcantly enhanced. The images were brightest at 24 hours, and then decreased in brightness until the end of the experiment (7 days). No signal enhancement was observed in the visual cortex at any concentration of MnCl2. These results suggest that MEMRI is a viable method for temporospatial tracing of the visual pathway in vivo. Signal enhancement in MEMRI de-pends on the dose of MnCl2, and the strongest signals appear 24 hours after intravitreal injection.

  1. Lxr regulates lipid metabolic and visual perception pathways during zebrafish development.

    Science.gov (United States)

    Pinto, Caroline Lucia; Kalasekar, Sharanya Maanasi; McCollum, Catherine W; Riu, Anne; Jonsson, Philip; Lopez, Justin; Swindell, Eric C; Bouhlatouf, Abdel; Balaguer, Patrick; Bondesson, Maria; Gustafsson, Jan-Åke

    2016-01-05

    The Liver X Receptors (LXRs) play important roles in multiple metabolic pathways, including fatty acid, cholesterol, carbohydrate and energy metabolism. To expand the knowledge of the functions of LXR signaling during embryonic development, we performed a whole-genome microarray analysis of Lxr target genes in zebrafish larvae treated with either one of the synthetic LXR ligands T0901317 or GW3965. Assessment of the biological processes enriched by differentially expressed genes revealed a prime role for Lxr in regulating lipid metabolic processes, similarly to the function of LXR in mammals. In addition, exposure to the Lxr ligands induced changes in expression of genes in the neural retina and lens of the zebrafish eye, including the photoreceptor guanylate cyclase activators and lens gamma crystallins, suggesting a potential novel role for Lxr in modulating the transcription of genes associated with visual function in zebrafish. The regulation of expression of metabolic genes was phenotypically reflected in an increased absorption of yolk in the zebrafish larvae, and changes in the expression of genes involved in visual perception were associated with morphological alterations in the retina and lens of the developing zebrafish eye. The regulation of expression of both lipid metabolic and eye specific genes was sustained in 1 month old fish. The transcriptional networks demonstrated several conserved effects of LXR activation between zebrafish and mammals, and also identified potential novel functions of Lxr, supporting zebrafish as a promising model for investigating the role of Lxr during development.

  2. Viewed actions are mapped in retinotopic coordinates in the human visual pathways.

    Science.gov (United States)

    Porat, Yuval; Pertzov, Yoni; Zohary, Ehud

    2011-10-21

    Viewed object-oriented actions elicit widespread fMRI activation in the dorsal and ventral visual pathways. This activation is typically stronger in the hemisphere contralateral to the visual field in which action is seen. However, since in previous studies participants kept fixation at the same screen position throughout the scan, it was impossible to infer if the viewed actions are represented in retina-based coordinates or in a more elaborated coordinate system. Here, participants changed their gaze between experimental conditions, such that some conditions shared the same retinotopic coordinates (but differed in their screen position), while other pairs of conditions shared the opposite trait. The degree of similarity between the patterns of activation elicited by the various conditions was assessed using multivoxel pattern analysis methods. Regions of interest, showing robust overall activation, included the intraparietal sulcus (IPS) and the occipitotemporal cortex. In these areas, the correlation between activation patterns for conditions sharing the same retinotopic coordinates was significantly higher than that of those having different retinotopic coordinates. In contrast, the correlations between activation patterns for conditions with the same spatiotopic coordinates were not significantly greater than for non-spatiotopic conditions. These results suggest that viewed object-oriented actions are likely to be maintained in retinotopic-framed coordinates.

  3. Reduction of Interhemispheric Functional Connectivity in Sensorimotor and Visual Information Processing Pathways in Schizophrenia

    Institute of Scientific and Technical Information of China (English)

    Xu Lang; Le Wang; Chuan-Jun Zhuo; Feng Jia; Li-Na Wang; Chun-Li Wang

    2016-01-01

    Background:Previous studies have demonstrated interhemispheric functional connectivity alterations in schizophrenia.However,the relationship between these alterations and the disease state of schizophrenia is largely unknown.Therefore,we aimed to investigate this relationship using voxel-mirrored homotopic connectivity (VMHC) method.Methods:This study enrolled 36 schizophrenia patients with complete remission,58 schizophrenia patients with incomplete remission and 55 healthy controls.The VMHC was calculated based on resting-state functional magnetic resonance imaging data.Differences in VMHC among three groups were compared using one-way analysis of variance.A brain region with a significant difference in VMHC was defined as a region of interest (ROI),and the mean VMHC value in the ROI was extracted for the post hoc analysis,i.e.,pair-wise comparisons across the three groups.Results:VMHC in the visual region (inferior occipital and fusiform gyri) and the sensorimotor region (paracentral lobule) showed significant differences among the three groups (P < 0.05,a false discovery rate method corrected).Pair-wise comparisons in thepost hoc analysis showed that VMHC of the visual and sensorimotor regions in schizophrenia patients with complete remission and incomplete remission was lower than that in healthy controls (P < 0.05,Bonferroni corrected);however,there was no significant difference between the two patient subgroups.Conclusions:Interhemispheric functional connectivity in the sensorimotor and visual processing pathways was reduced in patients with schizophrenia,but this reduction was unrelated to the disease state;thus,this reduction may serve as a trait marker of schizophrenia.

  4. Cortical damage in the posterior visual pathway in patients with sialidosis type 1.

    Science.gov (United States)

    Lu, Chin-Song; Ng, Shu-Hang; Lai, Szu-Chia; Kao, Ling-Yuh; Liu, Laura; Lin, Wey-Yil; Wu, Yi-Ming; Chen, Yao-Liang; Wang, Jiun-Jie

    2016-02-03

    In order to identify the cortical changes in patients with Sialidosis type 1, diffusion tensor imaging and resting state fMRI were acquired from 11 patients and 11 sex/age matched normal controls after clinical evaluations. The neuroimages from each participant were normalized and parcellated according to the Automatic Anatomical Labeling. Both the mean diffusivity and the corresponding functional connectivity were calculated from each cortical region. The white matter tract integrity was examined. The difference between patients and controls was examined using Student's t-test and between patients with either homozygous or heterozygous mutations by Mann-Whitney U test, both at a threshold of 0.05. Increased mean diffusivity throughout the brain can be noticed in the patients, together with a compromised white matter tracts integrity. The most severely affected cortical regions are in the occipital lobe. Decreased functional connectivity was from the temporal and occipital lobes to the hippocampus and parahippocampus. In contrast, connectivity from thalamus was enhanced. Diffused cortical atrophy with posterior focal lesions was noticed. We concluded that MRI observed functional changes in the posterior cortical pathways in the patients with Sialidosis. The observation might be related to the cortical blindness due to an altered neural network and a compromised visual pathway in the patients.

  5. Short-Chain Fatty Acids Inhibit Growth Hormone and Prolactin Gene Transcription via cAMP/PKA/CREB Signaling Pathway in Dairy Cow Anterior Pituitary Cells

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    Jian-Fa Wang

    2013-10-01

    Full Text Available Short-chain fatty acids (SCFAs play a key role in altering carbohydrate and lipid metabolism, influence endocrine pancreas activity, and as a precursor of ruminant milk fat. However, the effect and detailed mechanisms by which SCFAs mediate bovine growth hormone (GH and prolactin (PRL gene transcription remain unclear. In this study, we detected the effects of SCFAs (acetate, propionate, and butyrate on the activity of the cAMP/PKA/CREB signaling pathway, GH, PRL, and Pit-1 gene transcription in dairy cow anterior pituitary cells (DCAPCs. The results showed that SCFAs decreased intracellular cAMP levels and a subsequent reduction in PKA activity. Inhibition of PKA activity decreased CREB phosphorylation, thereby inhibiting GH and PRL gene transcription. Furthermore, PTX blocked SCFAs- inhibited cAMP/PKA/CREB signaling pathway. These data showed that the inhibition of GH and PRL gene transcription induced by SCFAs is mediated by Gi activation and that propionate is more potent than acetate and butyrate in inhibiting GH and PRL gene transcription. In conclusion, this study identifies a biochemical mechanism for the regulation of SCFAs on bovine GH and PRL gene transcription in DCAPCs, which may serve as one of the factors that regulate pituitary function in accordance with dietary intake.

  6. Microglomerular synaptic complexes in the sky-compass network of the honeybee connect parallel pathways from the anterior optic tubercle to the central complex

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    Martina Held

    2016-10-01

    Full Text Available While the ability of honeybees to navigate relying on sky-compass information has been investigated in a large number of behavioral studies, the underlying neuronal system has so far received less attention. The sky-compass pathway has recently been described from its input region, the dorsal rim area of the compound eye, to the anterior optic tubercle (AOTU. The aim of this study is to reveal the connection from the AOTU to the central complex. For this purpose we investigated the anatomy of large microglomerular synaptic complexes in the medial and lateral bulbs of the lateral complex. The synaptic complexes are formed by TuLAL1 neurons of the AOTU and GABAergic tangential neurons of the central body’s lower division (TL neurons. Both TuLAL1 and TL neurons strongly resemble neurons forming these complexes in other insect species. We further investigated the ultrastructure of these synaptic complexes using transmission electron microscopy. We found that single large presynaptic terminals of TuLAL1 neurons enclose many small profiles of TL neurons. The synaptic connections between these neurons are established by two types of synapses: divergent dyads and divergent tetrads. Our data support the assumption that these complexes are a highly conserved feature in the insect brain and play an important role in reliable signal transmission within the sky-compass pathway.

  7. Usefulness of visual evaluation of the anterior thalamic radiation by diffusion tensor tractography for differentiating between Alzheimer’s disease and elderly major depressive disorder patients

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    Niida A

    2013-04-01

    Full Text Available Akira Niida,1 Richi Niida,2 Kazumasa Kuniyoshi,3 Makoto Motomura,4 Akihiko Uechi51Department of Radiology, Nanbu Hospital, Itoman City, Okinawa, Japan; 2Department of Psychiatry, Nanto Clinic, Urasoe City, Okinawa, Japan; 3Department of Neuropathic Internal Medicine, Nanbu Hospital, Itoman City, Okinawa, Japan; 4Department of Human Sciences, University of the Ryukyus, Nakagami Country, Okinawa, Japan; 5Cognitive Neuroscience Research Project, Kansai Gaidai University, Hirakata City, Osaka, JapanBackground and objective: Many surveys of neural integrity of the cerebral white matter with psychiatric diseases on diffusion tensor imaging have recently been performed, but these mainly utilize fractional anisotropy (FA and the apparent diffusion coefficient (ADC values, and the results were inconsistent and not fully applied clinically. In this study, we investigated the possibility of differentiating between Alzheimer’s disease (AD and elderly major depressive disorder (MDD patients in whom early-stage symptoms are difficult to diagnose, by visually evaluating cerebral nerve fascicles utilizing diffusion tensor tractography. We also measured and evaluated FA and ADC values at the same time.Subjects and methods: The subjects included 13 AD patients (age: 69.5 ± 5.1 years, 19 MDD patients (65.8 ± 5.7 years, and 22 healthy control (HC subjects (67.4 ± 4.8 years. Images were acquired using a 1.5T magnetic resonance imaging device and analyzed by diffusion tensor tractography analysis software.Results: Depiction of the anterior thalamic radiation (ATR tended to be poor in AD patients unlike in MDD patients and HC subjects. The FA values in the left superior longitudinal fasciculus and fornix (FX in AD patients were significantly different from those in MDD patients and HC subjects. The ADC values in the bilateral ATR and left superior and inferior longitudinal fasciculi, left inferior fronto-occipital fasciculus, and FX in AD patients were

  8. Involvement of nitric oxide pathways in short term modulation of tyrosine hydroxylase activity by endothelins 1 and 3 in the rat anterior hypothalamus.

    Science.gov (United States)

    Morgazo, Carolina; Perfume, Guadalupe; Legaz, Guillermina; di Nunzio, Andrea; Hope, Sandra I; Bianciotti, Liliana G; Vatta, Marcelo S

    2005-09-02

    The ability of endothelins 1 and 3 (ET-1 and ET-3) to reduce neuronal norepinephrine release through ETB receptor activation involving nitric oxide (NO) pathways in the rat anterior hypothalamus region (AHR) was previously reported. In the present work, we studied the effects of ET-1 and -3 on tyrosine hydroxylase (TH) activity and the possible involvement of NO pathways. Results showed that ET-1 and -3 (10 nM) diminished TH activity in AHR and this effect was blocked by a selective ETB receptor antagonist (100 nM BQ-788), but not by a ET(A) receptor antagonist (BQ-610). To confirm these results, 1 microM IRL-1620 (ET(B) agonist) reduced TH activity whereas 300 nM sarafotoxin S6b falled to modify it. N(omega)-Nitro-L-arginine methyl ester (10 microM), 7-nitroindazole (10 microM), 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-ona (10 microM), KT5823 (2 microM), inhibitors of nitric oxide synthase, neuronal nitric oxide synthase, NO-sensitive-guanylyl cyclase, and protein kinase G, respectively, did not modify the reduction of TH activity produced by ETs. In addition, both 100 microM sodium nitroprusside and 50 microM 8-bromoguanosine-3',5'-cyclic monophosphate (NO donor and guanosine-3',5'-cyclic monophosphate analog, respectively) diminished TH activity. Present results showed that ET-1 and ET-3 diminished TH activity through the activation of ET(B) receptors involving the NO/guanosine-3',5'-cyclic monophosphate/protein kinase G pathway. Taken jointly present and previous results it can be concluded that both ETs play an important role as modulators of norepinephrine neurotransmission in the rat AHR.

  9. A study on early detection of changes in visual pathway due to Diabetes mellitus by visual evoked potential

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    Rajesh Kumar, Sundararajan D, Rajvin Samuel Ponraj, M Srinivasan

    2014-03-01

    Full Text Available Electrical potentials have been recorded by surface Evoked Potentials namely the Somatosensory Evoked Potential, Auditory Brainstem Response and Visual Evoked Potential [VEP]. Visual conduction disturbance can be evaluated by these instruments. A mass response of cortical and possibly subcortical may be represented, visual areas to visual stimuli. Diabetic patients without a past history of cerebrovascular accidents diagnosed with Non- Proliferative Diabetic retinopathy[DR] with a best corrected visual acuity at least 6/9.This study was done to assess whether a delay in VEP latency observed in diagnosed type II DM patients could be ascribed to dysfunction of the retinal or post retinal structures or by both. It is to find out whether the VEP latencies are altered in diabetes or not, if altered and to correlate duration of the diabetes mellitus with visual evoked potential changes. Visual evoked potentials are useful as a non invasive investigatory method in establishing central nervous system neuropathy developing in diabetes. This study clearly shows that changes in VEP may be detected in diabetics before the onset of retinopathy. Future studies should be focused on evaluation of the time that elapses between the appearance of the first detectable pathologic electrophysiologic changes and the first ophthalmoscopically detectable retinal changes in patients with Diabetes Mellitus [DM].

  10. Visualization of the ocular pulse in the anterior chamber of the mouse eye in vivo using phase-sensitive optical coherence tomography

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    Li, Peng; Ding, Zhihua; Ni, Yang; Xu, Baishen; Zhao, Chen; Shen, Yi; Du, Chixin; Jiang, Bo

    2014-09-01

    We report on a phase-based method for accurately measuring the ocular pulse in the anterior chamber in vivo. Using phase-sensitive optical coherence tomography with optimized scanning protocols and equations for compensating bulk motion and environmental vibrations, a high sensitivity of 0.9 μm/s minimal velocity is demonstrated at a wide detection band of 0 to 380 Hz. The pulsatile relative motion between cornea and crystalline lens in rodents is visualized and quantified. The relative motion is most likely caused by respiration (1.6 Hz) and heartbeat (6.6 Hz). The velocity amplitude of the relative motion is 10.3±2.4 μm/s. The displacement amplitudes at the respiratory and cardiac frequencies are 202.5±64.9 and 179.9±49.4 nm, respectively. The potential applications of the measurement technique can be found in the evaluation of intraocular pressure and the measurement of biomechanical properties of the ocular tissue, which are important in several ocular diseases.

  11. EFFECT OF AUDITORY & VISUAL BIOFEEDBACK WITH ELECTRICAL STIMULATION OF THE TIBIALIS ANTERIOR MUSCLE ON ACTIVE ROM & SELECTIVE MOTOR CONTROL OF ANKLE OF CHILDREN WITH SPASTIC CEREBRAL PALSY

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    Mayuri Sharma

    2015-06-01

    Full Text Available Background & Objective: Cerebral palsy (CP is the most common cause of movement disability in childhood, with an incidence of 1.5–2.5 per 1000 live born children. It is a non-progressive disorder that covers a number of neurological conditions, resulting in an abnormal development of movement and postural control. It is believed that an inability to maximally activate their muscles contributed to this weakness. Visual and auditory feedback cues have been shown to improve ROM & VMC in patients with movement disorders. The aim of this work was to investigate the efficacy of using biofeedback and neuromuscular electrical stimulation applied on tibialis anterior in children with cerebral palsy. The present work was designed to compare the effect of treatment with or without biofeedback applied to children with diplegic CP. Materials and Method: The 30 children with CP were divided in to 2 groups(experimental & control.The control group received NMES on tibialis anterior for 20 min. a day ,6 days in a week for a period of 6 weeks.the experimental group received NMES +biofeedback +conventional treatment.pre and post treatment evaluation included range of motion ,VMC and GMFM scoring. Results: Results showed that there was main effect for time, f(1,28;0.05=4.37, p<0.046 & a main effect for time, f(1,28;0.05=1.30, p<0.00,however there main effects were qualified by a group × time interaction, f (1,28;0.05=219.37, p<0.00.There was main effect for time, f(1,28;0.05=4.64. p<0.04 & a main effect for group, f(1,28;0.05=485.96, p<0.00,however there main effects were qualified by a group × time interaction, f (1,28;0.05=65.96, p <0.00 in right and left ankle joint. Conclusion: A significant improvement in range of motion, VMC & GMFM in experimental group as compare to control group. The study determined that biofeedback have positive clinical effects on the ROM & VMC of ankle of spastic diplegic.

  12. Pattern shift visual evoked response: application in neurology

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    Carlos A. M. Guerreiro

    1982-03-01

    Full Text Available The technique that we use for pattern shift visual evoked response (PSVER is described. PSVER is a non-invasive, practical and reliable clinical test in detecting anterior visual pathways lesions even when asymptomatic. The ability to find unsuspected lesions in multiple sclerosis, making possible an early diagnosis, is underscored. We also discuss some pathophysiologic aspects and the findings of the PSVER in some neurologic disorders with visual system involvement.

  13. Comparative Pathway Analyzer--a web server for comparative analysis, clustering and visualization of metabolic networks in multiple organisms.

    Science.gov (United States)

    Oehm, Sebastian; Gilbert, David; Tauch, Andreas; Stoye, Jens; Goesmann, Alexander

    2008-07-01

    In order to understand the phenotype of any living system, it is essential to not only investigate its genes, but also the specific metabolic pathway variant of the organism of interest, ideally in comparison with other organisms. The Comparative Pathway Analyzer, CPA, calculates and displays the differences in metabolic reaction content between two sets of organisms. Because results are highly dependent on the distribution of organisms into these two sets and the appropriate definition of these sets often is not easy, we provide hierarchical clustering methods for the identification of significant groupings. CPA also visualizes the reaction content of several organisms simultaneously allowing easy comparison. Reaction annotation data and maps for visualizing the results are taken from the KEGG database. Additionally, users can upload their own annotation data. This website is free and open to all users and there is no login requirement. It is available at https://www.cebitec.uni-bielefeld.de/groups/brf/software/cpa/index.html.

  14. Visual field defects after missile injuries to the geniculo-striate pathway in man.

    Science.gov (United States)

    Koerner, F.; Teuber, H.-L.

    1973-01-01

    The main objective of the survey reported was a quantitative comparison of different visual functions at identical retinal points of individual patients. The possibility to develop objective forms of visual-field testing was also explored, taking into account reports by Frydrychowicz and Harms (1940) and Harms (1951). These investigators had insisted that pupillary responses to light are depressed in areas of homonymous scotomata. The shapes of homonymous visual field defects are discussed together with questions regarding the association and dissociation of symptoms.

  15. Perceptual learning for treating amblyopia in children based on activation of visual signal pathway Relationship of curative effects and time

    Institute of Scientific and Technical Information of China (English)

    Weimin Liu; Jiang Shen; Jianzhong Huang; Yan Luo; Hongting Liu

    2008-01-01

    BACKGROUND: Conventional methods (such as occlusion therapy, fine manipulation, complementary, and alternative medicine) take effects slowly, are time and labor consuming, and have uncertain curative effects in the treatment of amblyopia. Perceptual learning, a new method for treating amblyopia, improves the ability to process signals from the cerebral optic nerve system by specific visual stimulation and visual learning, as well as activation of the visual signal pathway utilizing brain nervous system plasticity.OBJECTIVE: This study investigated and evaluated the curative effects of perceptual learning, which can directionally increase brain plasticity, on the treatment of amblyopia in children. The relationship between curative effect and time was also analyzed.DESIGN: A self-control experiment. SETTING: Visual Science and Optometry Center, People's Hospital of Guangxi Zhuang Autonomous Region. PARTICIPANTS: A total of 125 amblyopic children (250 amblyopic eyes), 73 males, 52 females, averaging (6 ± 2) years of age, received treatment at the Visual Science and Optometry Center, People's Hospital of Guangxi Zhuang Autonomous Region between September 2006 and February 2007 and were recruited for this study. All children presented with no structural disease of the eyeballs. Written informed consent for therapeutic regiments was obtained from each child's parent. The protocol received approval from the Hospital's Ethics Committee. METHODS: Visual function was tested with a perceptual learning system (Research Center for Human Health and Development of Sun Yat-sen University, National Engineering Technique Research Center for Medical Care Implement) for visual noise, position noise, contour discrimination, contrast sensitivity, grating stereogram, and random-dot fusion. These tests helped to evaluate the efficiency of visual information processing of these children, and to determine the degree of defects of the optic nerve cells and the connections of visual

  16. Elaboration of the Visual Pathways from the Study of War-Related Cranial Injuries: The Period from the Russo-Japanese War to World War I.

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    Lanska, Douglas J

    2016-01-01

    As a result of the wars in the early 20th century, elaboration of the visual pathways was greatly facilitated by the meticulous study of visual defects in soldiers who had suffered focal injuries to the visual cortex. Using relatively crude techniques, often under difficult wartime circumstances, investigators successfully mapped key features of the visual pathways. Studies during the Russo- Japanese War (1904-1905) by Tatsuji Inouye (1881-1976) and during World War I by Gordon Holmes (1876-1965), William Lister (1868-1944), and others produced increasingly refined retinotopic maps of the primary visual cortex, which were later supported and refined by studies during and after World War II. Studies by George Riddoch (1888-1947) during World War I also demonstrated that some patients could still perceive motion despite blindness caused by damage to their visual cortex and helped to establish the concept of functional partitioning of visual processes in the occipital cortex.

  17. Visual Cortex Plasticity Following Peripheral Damage To The Visual System: fMRI Evidence.

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    Lemos, João; Pereira, Daniela; Castelo-Branco, Miguel

    2016-10-01

    Over the last two decades, functional magnetic resonance imaging (fMRI) has become a powerful research method to investigate cortical visual plasticity. Abnormal fMRI response patterns have been occasionally detected in the visually deprived cortex of patients with bilateral retinal diseases. Controversy remains whether these observations indicate structural reorganization of the visual cortex or unmasking of previously silent cortico-cortical connections. In optic nerve diseases, there is weak evidence showing that early visual cortex seems to lack reorganization, while higher-order visual areas undergo plastic changes which may contribute to optimise visual function. There is however accumulating imaging evidence demonstrating trans-synaptic degeneration of the visual cortex in patients with disease of the anterior visual pathways. This may preclude the use of restorative treatments in these patients. Here, we review and update the body of fMRI evidence on visual cortical plasticity.

  18. Metabotropic glutamate receptor 5 shows different patterns of localization within the parallel visual pathways in macaque and squirrel monkeys

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    Shostak Y

    2014-09-01

    Full Text Available Yuri Shostak,1,5 Ashley Wenger,4 Julia Mavity-Hudson,1 Vivien A Casagrande1–3 1Department of Cell and Developmental Biology, 2Department of Psychology, 3Department of Ophthalmology and Visual Sciences, 4Undergraduate Neuroscience Program, Vanderbilt University, Nashville, TN, USA; 5Foreign Trade Unitary Enterprise, Minsk, Belarus Abstract: Glutamate is used as an excitatory neurotransmitter by the koniocellular (K, magnocellular (M, and parvocellular (P pathways to transfer signals from the primate lateral geniculate nucleus (LGN to primary visual cortex (V1. Glutamate acts through both fast ionotropic receptors, which appear to carry the main sensory message, and slower, modulatory metabotropic receptors (mGluRs. In this study, we asked whether mGluR5 relates in distinct ways to the K, M, and P LGN axons in V1. To answer this question, we used light microscopic immunocytochemistry and preembedding electron microscopic immunogold labeling to determine the localization of mGluR5 within the layers of V1 in relation to the K, M, and P pathways in macaque and squirrel monkeys. These pathways were labeled separately via wheat germ agglutinin–horseradish peroxidase (WGA–HRP injections targeting the LGN layers. mGluR5 is of interest because it: 1 has been shown to be expressed in the thalamic input layers; 2 appears to be responsible for some types of oscillatory firing, which could be important in the binding of visual features; and 3 has been associated with a number of sensory-motor gating-related pathologies, including schizophrenia and autism. Our results demonstrated the presence of mGluR5 in the neuropil of all V1 layers. This protein was lowest in IVCa (M input and the infragranular layers. In layer IVC, mGluR5 also was found postsynaptic to about 30% of labeled axons, but the distribution was uneven, such that postsynaptic mGluR5 label tended to occur opposite smaller (presumed P, and not larger (presumed M axon terminals. Only in the K

  19. Population activity in the human dorsal pathway predicts the accuracy of visual motion detection

    NARCIS (Netherlands)

    Donner, T.H.; Siegel, M.; Oostenveld, R.; Fries, P.; Bauer, M.; Engel, A.K.

    2007-01-01

    A person's ability to detect a weak visual target stimulus varies from one viewing to the next. We tested whether the trial-to-trial fluctuations of neural population activity in the human brain are related to the fluctuations of behavioral performance in a "yes-no" visual motion-detection task. We

  20. Functional Dissociations within the Ventral Object Processing Pathway: Cognitive Modules or a Hierarchical Continuum?

    Science.gov (United States)

    Cowell, Rosemary A.; Bussey, Timothy J.; Saksida, Lisa M.

    2010-01-01

    We examined the organization and function of the ventral object processing pathway. The prevailing theoretical approach in this field holds that the ventral object processing stream has a modular organization, in which visual perception is carried out in posterior regions and visual memory is carried out, independently, in the anterior temporal…

  1. An editor for pathway drawing and data visualization in the Biopathways Workbench

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    Li Joshua

    2009-10-01

    Full Text Available Abstract Background Pathway models serve as the basis for much of systems biology. They are often built using programs designed for the purpose. Constructing new models generally requires simultaneous access to experimental data of diverse types, to databases of well-characterized biological compounds and molecular intermediates, and to reference model pathways. However, few if any software applications provide all such capabilities within a single user interface. Results The Pathway Editor is a program written in the Java programming language that allows de-novo pathway creation and downloading of LIPID MAPS (Lipid Metabolites and Pathways Strategy and KEGG lipid metabolic pathways, and of measured time-dependent changes to lipid components of metabolism. Accessed through Java Web Start, the program downloads pathways from the LIPID MAPS Pathway database (Pathway as well as from the LIPID MAPS web server http://www.lipidmaps.org. Data arises from metabolomic (lipidomic, microarray, and protein array experiments performed by the LIPID MAPS consortium of laboratories and is arranged by experiment. Facility is provided to create, connect, and annotate nodes and processes on a drawing panel with reference to database objects and time course data. Node and interaction layout as well as data display may be configured in pathway diagrams as desired. Users may extend diagrams, and may also read and write data and non-lipidomic KEGG pathways to and from files. Pathway diagrams in XML format, containing database identifiers referencing specific compounds and experiments, can be saved to a local file for subsequent use. The program is built upon a library of classes, referred to as the Biopathways Workbench, that convert between different file formats and database objects. An example of this feature is provided in the form of read/construct/write access to models in SBML (Systems Biology Markup Language contained in the local file system. Conclusion

  2. Selective optical control of synaptic transmission in the subcortical visual pathway by activation of viral vector-expressed halorhodopsin.

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    Katsuyuki Kaneda

    Full Text Available The superficial layer of the superior colliculus (sSC receives visual inputs via two different pathways: from the retina and the primary visual cortex. However, the functional significance of each input for the operation of the sSC circuit remains to be identified. As a first step toward understanding the functional role of each of these inputs, we developed an optogenetic method to specifically suppress the synaptic transmission in the retino-tectal pathway. We introduced enhanced halorhodopsin (eNpHR, a yellow light-sensitive, membrane-targeting chloride pump, into mouse retinal ganglion cells (RGCs by intravitreously injecting an adeno-associated virus serotype-2 vector carrying the CMV-eNpHR-EYFP construct. Several weeks after the injection, whole-cell recordings made from sSC neurons in slice preparations revealed that yellow laser illumination of the eNpHR-expressing retino-tectal axons, putatively synapsing onto the recorded cells, effectively inhibited EPSCs evoked by electrical stimulation of the optic nerve layer. We also showed that sSC spike activities elicited by visual stimulation were significantly reduced by laser illumination of the sSC in anesthetized mice. These results indicate that photo-activation of eNpHR expressed in RGC axons enables selective blockade of retino-tectal synaptic transmission. The method established here can most likely be applied to a variety of brain regions for studying the function of individual inputs to these regions.

  3. Identifying and characterising cerebral visual impairment in children: a review.

    Science.gov (United States)

    Philip, Swetha Sara; Dutton, Gordon N

    2014-05-01

    Cerebral visual impairment (CVI) comprises visual malfunction due to retro-chiasmal visual and visual association pathway pathology. This can be isolated or accompany anterior visual pathway dysfunction. It is a major cause of low vision in children in the developed and developing world due to increasing survival in paediatric and neonatal care. CVI can present in many combinations and degrees. There are multiple causes and it is common in children with cerebral palsy. CVI can be identified easily, if a structured approach to history-taking is employed. This review describes the features of CVI and describes practical management strategies aimed at helping affected children. A literature review was undertaken using 'Medline' and 'Pubmed'. Search terms included cerebral visual impairment, cortical visual impairment, dorsal stream dysfunction and visual function in cerebral palsy.

  4. Functional MRI for patients with visual pathway diseases%视路疾病患者脑功能性磁共振成像初步观察

    Institute of Scientific and Technical Information of China (English)

    沈旭中; 汤伟军; 叶纹

    2010-01-01

    Objective To observe the results of function MRI and perimetry in patients with visual pathway diseases. Methods Three patients (6 eyes) with pituitary adenoma and craniopharyngioma diagnosed via pathological examination and three healthy volunteers aged from 24 to 30 were collected. The best corrected visual acuity was non-light perception-1. 0 in the 6 sick eyes and 1. 0 in the healthy eyes;all the involved individuals had no other ocular diseases except myopia and without any contraindications of MRI. Common tests including the best visual acuity, fundus test by direct or indirect ophthalmoscope, center static visual field tested by Octopus 101 perimeter, program 32, tendency oriented perimetry were performed. The visual stimulation subtended a field of view of about 12 degrees,consisted of high contrast and drifting checkerboards. MRI parameters: GE signa VH/i 3. 0T scanner. Functional data: GRE-EPI sequence, 20 slices lying perpendicular to the calcarine sulcus. Anatomical data was obtained using 3DSPGR sequence to acquire high resolution. The cortical surface was unfolded and then cut and inflated. Functional data was presented to the inflated surface and subsequently analyzed by AFNI software. Results In six eyes, three had temporal defects, two had upper temporal visual field defects, and the other one did not finish the visual field test. The retinotopic representations of health adults were obtained by using the phase-encoded visual stimulation. The Eccentricity coordinate maps showed that foveal representations lay in the occipital poles and the representations appeared further anterior as eccentricity increased. The polar angle coordinate maps showed that early retinotopically organized areas had a representation of visual field. The visual cortex beneath the calcarine sulcus matched with the upper visual field of the opposite side and which upon the calcarine sulcus matched with the under visual field of the opposite side. Less or no visual cortex

  5. Involvement of the visual pathway is not a risk factor of visual field deficits in patients with occipital arteriovenous malformations:an fMRI study

    Institute of Scientific and Technical Information of China (English)

    Xianzeng Tong; Jun Wu; Fuxin Lin; Yong Cao; Yuanli Zhao; Zhen Jin; Shuo Wang

    2015-01-01

    to probe into the plasticity of the visual pathway in patients with this congenital vascular anomaly.

  6. Differential impact of parvocellular and magnocellular pathways on visual impairment in apperceptive agnosia?

    Science.gov (United States)

    Hildebrandt, Helmut; Schütze, Cathleen; Ebke, Markus; Spang, Karoline

    2004-06-01

    The term "visual form agnosia" describes a disorder characterized by problems recognizing objects, poor copying,and distinguishing between simple geometric shapes despite normal intellectual abilities. Visual agnosia has been interpreted as a disorder of the magnocellular visual system, caused by an inability to separate figure from ground by sampling information from extended regions of space and to integrate it with fine-grain local information. However,this interpretation has hardly been tested with neuropsychological or functional brain imaging methods, mainly because the magnocellular and parvocellular structures are highly interconnected in the visual system. We studied a patient (AM) who had suffered a sudden heart arrest, causing hypoxic brain damage. He was/is severely agnosic, as apparent in both the Birmingham Object Recognition Battery and the Visual Object and Space Battery. First- and especially second-order motion perception was also impaired, but AM experienced no problems in grasping and navigating through space. The patient revealed a normal P100 in visual evoked potentials both with colored and fine-grained achromatic checkerboards. But the amplitude of the P100 was clearly decreased if a coarse achromatic checkerboard was presented.The physiological and neuropsychological findings indicate that AM experienced problems integrating information over extended regions of space and in detecting second-order motion. This may be interpreted as a disorder of the magnocellular system, with intact parvocellular system and therefore preserved ability to detect both local features and colors.

  7. Color vision versus pattern visual evoked potentials in the assessment of subclinical optic pathway involvement in multiple sclerosis

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    Fatih C Gundogan

    2013-01-01

    Full Text Available Background: Optic pathway involvement in multiple sclerosis is frequently the initial sign in the disease process. In most clinical applications, pattern visual evoked potential (PVEP is used in the assessment of optic pathway involvement. Objective: To question the value of PVEP against color vision assessment in the diagnosis of subclinical optic pathway involvement. Materials and Methods: This prospective, cross-sectional study included 20 multiple sclerosis patients without a history of optic neuritis, and 20 healthy control subjects. Farnsworth-Munsell (FM 100-Hue testing and PVEPs to 60-min arc and 15-min arc checks by using Roland-Consult RetiScan® system were performed. P 100 amplitude, P 100 latency in PVEP and total error scores (TES in FM 100-Hue test were assessed. Results: Expanded Disability Status Scale score and the time from diagnosis were 2.21 ± 2.53 (ranging from 0 to 7 and 4.1 ± 4.4 years. MS group showed significantly delayed P 100 latency for both checks (P 0.05 for all. 14 MS patients (70% had an increased TESs in FM-100 Hue, 11 (55% MS patients had delayed P 100 latency and 9 (45% had reduced P 100 amplitude. The areas under the ROC curves were 0.944 for FM-100 Hue test, 0.753 for P 100 latency, and 0.173 for P 100 amplitude. Conclusions: Color vision testing seems to be more sensitive than PVEP in detecting subclinical visual pathway involvement in MS.

  8. Visual System Involvement in Patients with Friedreich's Ataxia

    Science.gov (United States)

    Fortuna, Filippo; Barboni, Piero; Liguori, Rocco; Valentino, Maria Lucia; Savini, Giacomo; Gellera, Cinzia; Mariotti, Caterina; Rizzo, Giovanni; Tonon, Caterina; Manners, David; Lodi, Raffaele; Sadun, Alfredo A.; Carelli, Valerio

    2009-01-01

    Optic neuropathy is common in mitochondrial disorders, but poorly characterized in Friedreich's ataxia (FRDA), a recessive condition caused by lack of the mitochondrial protein frataxin. We investigated 26 molecularly confirmed FRDA patients by studying both anterior and posterior sections of the visual pathway using a new, integrated approach.…

  9. SINs and SOMs: Neural microcircuits for size tuning in the zebrafish and mouse visual pathway.

    Directory of Open Access Journals (Sweden)

    Alison J. Barker

    2013-05-01

    Full Text Available In many animals, a fast and reliable circuit for discriminating between predator-sized objects and edible (prey-sized objects is necessary for survival. How are receptive fields in visual brain areas organized to extract information about size? Recent studies from the zebrafish optic tectum and the mouse visual cortex suggest de novo shaping of receptive fields by subtypes of inhibitory neurons. Del Bene et al. (2010 describe a population of GABAergic neurons in the zebrafish optic tectum (Superficial Interneurons, SINs that are necessary for size filtering during prey capture. Adesnik et al. (2012 describe a somatostatin-expressing interneuron population (SOMs that confers surround suppression on layer II/III pyramidal cells in mouse V1. Strikingly both the SINs and the SOMs, display size-dependent response properties. Increasing visual stimulus size increases excitatory input to these neurons. Dampening SIN or SOM activity alters tuning of neighboring circuits such that they lose preference for small objects. Both results provide exciting evidence for mechanisms of size filtering in visual circuits. Here we review the roles of the SINs and the SOMs and speculate on the similarity of such spatial filters across species.

  10. Pathways to Identity. Using Visualization to Aid Law Enforcement in Identification Tasks

    Energy Technology Data Exchange (ETDEWEB)

    Bruce, Joseph R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Scholtz, Jean [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hodges, Duncan [Univ. of Oxford (United Kingdom); Emanuel, Lia [Univ. of Bath (United Kingdom); Stanton Fraser, Danae [Univ. of Bath (United Kingdom); Creese, Sadie [Univ. of Oxford (United Kingdom); Love, Oriana J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-09-18

    The nature of identity has changed dramatically in recent years and has grown in complexity. Identities are defined in multiple domains: biological and psychological elements strongly contribute, but biographical and cyber elements also are necessary to complete the picture. Law enforcement is beginning to adjust to these changes, recognizing identity’s importance in criminal justice. The SuperIdentity project seeks to aid law enforcement officials in their identification tasks through research of techniques for discovering identity traits, generation of statistical models of identity and analysis of identity traits through visualization. We present use cases compiled through user interviews in multiple fields, including law enforcement, and describe the modeling and visualization tools design to aid in those use cases.

  11. Pathways to Identity: Aiding Law Enforcement in Identification Tasks With Visual Analytics

    Energy Technology Data Exchange (ETDEWEB)

    Bruce, Joseph R.; Scholtz, Jean; Hodges, Duncan; Emanuel, Lia; Stanton-Fraser, Danae; Creese, Sadie; Love, Oriana J.

    2014-09-18

    The nature of identity has changed dramatically in recent years, and has grown in complexity. Identities are defined in multiple domains: biological and psychological elements strongly contribute, but also biographical and cyber elements are necessary to complete the picture. Law enforcement is beginning to adjust to these changes, recognizing its importance in criminal justice. The SuperIdentity project seeks to aid law enforcement officials in their identification tasks through research of techniques for discovering identity traits, generation of statistical models of identity and analysis of identity traits through visualization. We present use cases compiled through user interviews in multiple fields, including law enforcement, as well as the modeling and visualization tools design to aid in those use cases.

  12. Study on Manufacture of Integrated Visual Pathway Specimens%完整视觉传导通路标本研制

    Institute of Scientific and Technical Information of China (English)

    高燕; 马青; 沈柔; 李倩; 普玲燕; 朱建华

    2014-01-01

    Objective:To investigate the methods of manufacturing integrated visual pathway specimens,and provide specimen making ideas for study of the visual pathway and light reflex pathway. Manufacture integrated visual pathway specimens as intuitive teaching aids for experimental teaching of human anatomy. Methods:Based on the previous experience,integrated visual pathway specimens were made from the base of skull by peeling tissues progressively. Results:Two integrated visual pathway specimens have been made. The eyes,optic nerves,optic chiasm,optic tracts,lateral geniculate bodies,optic radiation and visual cortex ware showed in the specimens. Conclusion:It is difficult to make the integrated visual pathway specimens,especially to display structures of visual pathway from the top of skull. The method of passing through the base of skull is the better way to display structures of integrated visual pathway.%目的:探讨完整视觉传导路标本的制作方法,为视觉传导及对光反射通路的研究提供标本制作思路;制作出完整视觉传导通路的标本,为解剖学实验教学提供直观形象的教具。方法:在参考和综合前人经验的基础上,使用逐层剥离法从颅底显露完整视觉传导通路。结果:制作出2个完整视觉传导通路标本,标本直观地显示了眼球、视神经、视交叉、视束、外侧膝状体、视辐射及视觉中枢等结构。结论:视觉传导通路标本制作较为困难,从上面很难完整显示整个视觉传导通路,从颅底入路是显示完整视觉传导通路的较好方法。

  13. Magnetic resonance findings in the pregeniculate visual pathways in Leber hereditary optic neuropathy.

    Science.gov (United States)

    van Westen, Danielle; Hammar, Björn; Bynke, Gunnel

    2011-03-01

    Two relatives, a 61-year-old man and the 21-year-old grandson of his sister, suffered from bilateral visual loss and were diagnosed with Leber hereditary optic neuropathy. In both cases, the diagnosis was molecularly confirmed with the 11778 mitochondrial mutation. MRI showed increased T2 signal not only in the optic nerves and chiasm but also in the optic tracts, extending to the lateral geniculate bodies. To our knowledge, the latter finding has not been described previously.

  14. Testing the generality of the zoom-lens model: Evidence for visual-pathway specific effects of attended-region size on perception.

    Science.gov (United States)

    Goodhew, Stephanie C; Lawrence, Rebecca K; Edwards, Mark

    2017-03-16

    There are volumes of information available to process in visual scenes. Visual spatial attention is a critically important selection mechanism that prevents these volumes from overwhelming our visual system's limited-capacity processing resources. We were interested in understanding the effect of the size of the attended area on visual perception. The prevailing model of attended-region size across cognition, perception, and neuroscience is the zoom-lens model. This model stipulates that the magnitude of perceptual processing enhancement is inversely related to the size of the attended region, such that a narrow attended-region facilitates greater perceptual enhancement than a wider region. Yet visual processing is subserved by two major visual pathways (magnocellular and parvocellular) that operate with a degree of independence in early visual processing and encode contrasting visual information. Historically, testing of the zoom-lens has used measures of spatial acuity ideally suited to parvocellular processing. This, therefore, raises questions about the generality of the zoom-lens model to different aspects of visual perception. We found that while a narrow attended-region facilitated spatial acuity and the perception of high spatial frequency targets, it had no impact on either temporal acuity or the perception of low spatial frequency targets. This pattern also held up when targets were not presented centrally. This supports the notion that visual attended-region size has dissociable effects on magnocellular versus parvocellular mediated visual processing.

  15. Visualization of Gli activity in craniofacial tissues of hedgehog-pathway reporter transgenic zebrafish.

    Directory of Open Access Journals (Sweden)

    Tyler Schwend

    Full Text Available BACKGROUND: The Hedgehog (Hh-signaling pathway plays a crucial role in the development and maintenance of multiple vertebrate and invertebrate organ systems. Gli transcription factors are regulated by Hh-signaling and act as downstream effectors of the pathway to activate Hh-target genes. Understanding the requirements for Hh-signaling in organisms can be gained by assessing Gli activity in a spatial and temporal fashion. METHODOLOGY/PRINCIPAL FINDINGS: We have generated a Gli-dependent (Gli-d transgenic line, Tg(Gli-d:mCherry, that allows for rapid and simple detection of Hh-responding cell populations in both live and fixed zebrafish. This transgenic line expresses a mCherry reporter under the control of a Gli responsive promoter, which can be followed by using fluorescent microscopy and in situ hybridization. Expression of the mCherry transgene reporter during embryogenesis and early larval development faithfully replicated known expression domains of Hh-signaling in zebrafish, and abrogating Hh-signaling in transgenic fish resulted in the suppression of reporter expression. Moreover, ectopic shh expression in Tg(Glid:mCherry fish led to increased transgene production. Using this transgenic line we investigated the nature of Hh-pathway response during early craniofacial development and determined that the neural crest skeletal precursors do not directly respond to Hh-signaling prior to 48 hours post fertilization, suggesting that earlier requirements for pathway activation in this population of facial skeleton precursors are indirect. CONCLUSION/SIGNIFICANCE: We have determined that early Hh-signaling requirements in craniofacial development are indirect. We further demonstrate the Tg(Gli-d:mCherry fish are a highly useful tool for studying Hh-signaling dependent processes during embryogenesis and larval stages.

  16. Totally thrombosed giant anterior communicating artery aneurysm

    Directory of Open Access Journals (Sweden)

    V R Roopesh Kumar

    2015-01-01

    Full Text Available Giant anterior communicating artery aneurysmsarerare. Apatient presented with visual dysfunction, gait ataxia and urinary incontinence. MRI showed a giant suprasellar mass.At surgery, the lesion was identified as being an aneurysm arising from the anterior communicating artery.The difficulty in preoperative diagnosis and relevant literature are reviewed.

  17. Effective connectivity of dorsal and ventral visual pathways in chunk decomposition

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Chunk decomposition is defined as a cognitive process which breaks up familiar items into several parts to reorganize them in an alternative approach.The present study investigated the effective connectivity of visual streams in chunk decomposition through dynamic causal modeling(DCM).The results revealed that chunk familiarity and perceptual tightness made a combined contribution to highlight not only the "what" and the "where" streams,but also the effective connectivity from the left inferior temporal gyrus to the left superior parietal lobule.

  18. Atypical form of Alzheimer's disease with prominent posterior cortical atrophy: a review of lesion distribution and circuit disconnection in cortical visual pathways

    Science.gov (United States)

    Hof, P. R.; Vogt, B. A.; Bouras, C.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

    1997-01-01

    In recent years, the existence of visual variants of Alzheimer's disease characterized by atypical clinical presentation at onset has been increasingly recognized. In many of these cases post-mortem neuropathological assessment revealed that correlations could be established between clinical symptoms and the distribution of neurodegenerative lesions. We have analyzed a series of Alzheimer's disease patients presenting with prominent visual symptomatology as a cardinal sign of the disease. In these cases, a shift in the distribution of pathological lesions was observed such that the primary visual areas and certain visual association areas within the occipito-parieto-temporal junction and posterior cingulate cortex had very high densities of lesions, whereas the prefrontal cortex had fewer lesions than usually observed in Alzheimer's disease. Previous quantitative analyses have demonstrated that in Alzheimer's disease, primary sensory and motor cortical areas are less damaged than the multimodal association areas of the frontal and temporal lobes, as indicated by the laminar and regional distribution patterns of neurofibrillary tangles and senile plaques. The distribution of pathological lesions in the cerebral cortex of Alzheimer's disease cases with visual symptomatology revealed that specific visual association pathways were disrupted, whereas these particular connections are likely to be affected to a less severe degree in the more common form of Alzheimer's disease. These data suggest that in some cases with visual variants of Alzheimer's disease, the neurological symptomatology may be related to the loss of certain components of the cortical visual pathways, as reflected by the particular distribution of the neuropathological markers of the disease.

  19. Visualization of oxytocin release that mediates paired pulse facilitation in hypothalamic pathways to brainstem autonomic neurons.

    Directory of Open Access Journals (Sweden)

    Ramón A Piñol

    Full Text Available Recent work has shown that oxytocin is involved in more than lactation and uterine contraction. The paraventricular nucleus of the hypothalamus (PVN contains neuroendocrine neurons that control the release of hormones, including vasopressin and oxytocin. Other populations of PVN neurons do not release hormones, but rather project to and release neurotransmitters onto other neurons in the CNS involved in fluid retention, thermoregulation, sexual behavior and responses to stress. Activation of oxytocin receptors can be cardioprotective and reduces the adverse cardiovascular consequences of anxiety and stress, yet how oxytocin can affect heart rate and cardiac function is unknown. While anatomical work has shown the presence of peptides, including oxytocin, in the projections from the PVN to parasympathetic nuclei, electrophysiological studies to date have only demonstrated release of glutamate and activation of fast ligand gated receptors in these pathways. In this study, using rats, we directly show, using sniffer CHO cells that express oxytocin receptors and the Ca2+ indicator R-GECO, that optogenetic activation of channelrhodopsin-2 (ChR2 expressing PVN fibers in the brainstem activates oxytocin receptors in the dorsomotor nucleus of the vagus (DMNV. We also demonstrate that while a single photoactivation of PVN terminals only activates glutamatergic receptors in brainstem cardiac vagal neurons (CVNs, neurons that dominate the neural control of heart rate, both the paired pulse facilitation, and sustained enhancement of glutamate release in this pathway is mediated by activation of oxytocin receptors. Our results provide direct evidence that a pathway from the PVN likely releases oxytocin and enhances short-term plasticity of this critical autonomic connection.

  20. Visualization of Oxytocin Release that Mediates Paired Pulse Facilitation in Hypothalamic Pathways to Brainstem Autonomic Neurons

    Science.gov (United States)

    Piñol, Ramón A.; Jameson, Heather; Popratiloff, Anastas; Lee, Norman H.; Mendelowitz, David

    2014-01-01

    Recent work has shown that oxytocin is involved in more than lactation and uterine contraction. The paraventricular nucleus of the hypothalamus (PVN) contains neuroendocrine neurons that control the release of hormones, including vasopressin and oxytocin. Other populations of PVN neurons do not release hormones, but rather project to and release neurotransmitters onto other neurons in the CNS involved in fluid retention, thermoregulation, sexual behavior and responses to stress. Activation of oxytocin receptors can be cardioprotective and reduces the adverse cardiovascular consequences of anxiety and stress, yet how oxytocin can affect heart rate and cardiac function is unknown. While anatomical work has shown the presence of peptides, including oxytocin, in the projections from the PVN to parasympathetic nuclei, electrophysiological studies to date have only demonstrated release of glutamate and activation of fast ligand gated receptors in these pathways. In this study, using rats, we directly show, using sniffer CHO cells that express oxytocin receptors and the Ca2+ indicator R-GECO, that optogenetic activation of channelrhodopsin-2 (ChR2) expressing PVN fibers in the brainstem activates oxytocin receptors in the dorsomotor nucleus of the vagus (DMNV). We also demonstrate that while a single photoactivation of PVN terminals only activates glutamatergic receptors in brainstem cardiac vagal neurons (CVNs), neurons that dominate the neural control of heart rate, both the paired pulse facilitation, and sustained enhancement of glutamate release in this pathway is mediated by activation of oxytocin receptors. Our results provide direct evidence that a pathway from the PVN likely releases oxytocin and enhances short-term plasticity of this critical autonomic connection. PMID:25379676

  1. The dynamics of individual nucleosomes controls the chromatin condensation pathway: direct AFM visualization of variant chromatin

    CERN Document Server

    Montel, Fabien; Castelnovo, Martin; Bednar, Jan; Dimitrov, Stefan; Angelov, Dimitar; Faivre-Moskalenko, Cendrine

    2009-01-01

    Chromatin organization and dynamics is studied in this work at scales ranging from single nucleosome to nucleosomal array by using a unique combination of biochemical assays, single molecule imaging technique and numerical modeling. We demonstrate that a subtle modification in the nucleosome structure induced by the histone variant H2A.Bbd drastically modifies the higher order organization of the nucleosomal arrays. Importantly, as directly visualized by AFM, conventional H2A nucleosomal arrays exhibit specific local organization, in contrast to H2A.Bbd arrays, which show ?beads on a string? structure. The combination of systematic image analysis and theoretical modeling allows a quantitative description relating the observed gross structural changes of the arrays to their local organization. Our results strongly suggest that higher-order organization of H1-free nucleosomal arrays is mainly determined by the fluctuation properties of individual nucleosomes. Moreover, numerical simulations suggest the existenc...

  2. 3D visualization of deformation structures and potential fluid pathways at the Grimsel Test Site

    Science.gov (United States)

    Schneeberger, Raphael; Kober, Florian; Berger, Alfons; Spillmann, Thomas; Herwegh, Marco

    2015-04-01

    Knowledge on the ability of fluids to infiltrate subsurface rocks is of major importance for underground constructions, geothermal or radioactive waste disposal projects. In this study, we focus on the characterization of water infiltration pathways, their 3D geometries and origins. Based on surface and subsurface mapping in combination with drill core data, we developed by the use of MoveTM (Midland Valley Exploration Ltd.) a 3D structural model of the Grimsel Test Site (GTS). GTS is an underground laboratory operated by NAGRA, the Swiss organisation responsible for the management of nuclear waste. It is located within a suite of post-Variscan magmatic bodies comprising former granitic and granodioritic melts, which are dissected by mafic and aplitic dikes. During Alpine orogeny, the suite was tectonically overprinted within two stages of ductile deformation (Wehrens et al., in prep.) followed by brittle overprint of some of the shear zones during the retrograde exhumation history. It is this brittle deformation, which controls today's water infiltration network. However, the associated fractures, cataclasites and fault gouges are controlled themselves by aforementioned pre-existing mechanical discontinuities, whose origin ranges back as far as to the magmatic stage. For example, two sets of vertically oriented mafic dikes (E-W and NW-SE striking) and compositional heterogeneities induced by magmatic segregation processes in the plutonic host rocks served as nucleation sites for Alpine strain localization. Subsequently, NE-SW, E-W and NW-SE striking ductile shear zones were formed, in combination with high temperature fracturing while dissecting the host rocks in a complex 3D pattern (Wehrens et al, in prep.). Whether the ductile shear zones have been subjected to brittle reactivation and can serve as infiltration pathways or not, depends strongly on their orientations with respect to the principal stress field. Especially where deformation structures intersect

  3. Interferometric Motion Detection in Atomic Layer 2D Nanostructures: Visualizing Signal Transduction Efficiency and Optimization Pathways

    Science.gov (United States)

    Wang, Zenghui; Feng, Philip X.-L.

    2016-07-01

    Atomic layer crystals are emerging building blocks for enabling new two-dimensional (2D) nanomechanical systems, whose motions can be coupled to other attractive physical properties in such 2D systems. Optical interferometry has been very effective in reading out the infinitesimal motions of these 2D structures and spatially resolving different modes. To quantitatively understand the detection efficiency and its dependence on the device parameters and interferometric conditions, here we present a systematic study of the intrinsic motion responsivity in 2D nanomechanical systems using a Fresnel-law-based model. We find that in monolayer to 14-layer structures, MoS2 offers the highest responsivity among graphene, h-BN, and MoS2 devices and for the three commonly used visible laser wavelengths (633, 532, and 405 nm). We also find that the vacuum gap resulting from the widely used 300 nm-oxide substrate in making 2D devices, fortunately, leads to close-to-optimal responsivity for a wide range of 2D flakes. Our results elucidate and graphically visualize the dependence of motion transduction responsivity upon 2D material type and number of layers, vacuum gap, oxide thickness, and detecting wavelength, thus providing design guidelines for constructing 2D nanomechanical systems with optimal optical motion readout.

  4. Visualization of postoperative anterior cruciate ligament reconstruction bone tunnels: Reliability of standard radiographs, CT scans, and 3D virtual reality images

    NARCIS (Netherlands)

    D.E. Meuffels (Duncan); J.W. Potters (Jan Willem); A.H.J. Koning (Anton); C.H. Brown Jr Jr. (Charles); J.A.N. Verhaar (Jan); M. Reijman (Max)

    2011-01-01

    textabstractBackground and purpose: Non-anatomic bone tunnel placement is the most common cause of a failed ACL reconstruction. Accurate and reproducible methods to visualize and document bone tunnel placement are therefore important. We evaluated the reliability of standard radiographs, CT scans, a

  5. A common evolutionary origin for the ON- and OFF-edge motion detection pathways of the Drosophila visual system

    Directory of Open Access Journals (Sweden)

    Kazunori eShinomiya

    2015-07-01

    Full Text Available Synaptic circuits for identified behaviors in the Drosophila brain have typically been considered from either a developmental or functional perspective without reference to how the circuits might have been inherited from ancestral forms. For example, two candidate pathways for ON- and OFF-edge motion detection in the visual system act via circuits that use respectively either T4 or T5, two cell types of the fourth neuropil, or lobula plate, that exhibit narrow-field direction-selective responses and provide input to wide-field tangential neurons. T4 or T5 both have four subtypes that terminate one each in the four strata of the lobula plate. Representatives are reported in a wide range of Diptera, and both cell types exhibit various similarities in: 1 the morphology of their dendritic arbors; 2 their four morphological and functional subtypes; 3 their cholinergic profile in Drosophila; 4 their input from the pathways of L3 cells in the first neuropil, or lamina, and by one of a pair of lamina cells, L1 (to the T4 pathway and L2 (to the T5 pathway; and 5 their innervation by a single, wide-field contralateral tangential neuron from the central brain. Progenitors of both also express the gene atonal early in their proliferation from the inner anlage of the developing optic lobe, being alone among many other cell type progeny to do so. Yet T4 receives input in the second neuropil, or medulla, and T5 in the third neuropil or lobula. Here we suggest that these two cell types were originally one, that their ancestral cell population duplicated and split to innervate separate medulla and lobula neuropils, and that a fiber crossing – the internal chiasma – arose between the two neuropils. The split most plausibly occurred, we suggest, with the formation of the lobula as a new neuropil that formed when it separated from its ancestral neuropil to leave the medulla, suggesting additionally that medulla input neurons to T4 and T5 may also have had a

  6. Ability of Mn2+ to Permeate the Eye and Availability of Manganese-enhanced Magnetic Resonance Imaging for Visual Pathway Imaging via Topical Administration

    Directory of Open Access Journals (Sweden)

    Yao Chen

    2016-01-01

    Conclusions: The corneal epithelium is a barrier to Mn2+, and the iris and lens septum might be another intraocular barrier to the permeation of Mn2+. An elevated Mn2+ concentration contributes to the increased permeation of Mn2+, higher MEMRI signal, and corneal toxicity. The enhancement of the visual pathway requires an effective Mn2+ concentration in the vitreous body.

  7. Current approach in diagnosis and management of anterior uveitis

    Directory of Open Access Journals (Sweden)

    Agrawal Rupesh

    2010-01-01

    Full Text Available Uveitis is composed of a diverse group of disease entities, which in total has been estimated to cause approximately 10% of blindness. Uveitis is broadly classified into anterior, intermediate, posterior and panuveitis based on the anatomical involvement of the eye. Anterior uveitis is, however, the commonest form of uveitis with varying incidences reported in worldwide literature. Anterior uveitis can be very benign to present with but often can lead to severe morbidity if not treated appropriately. The present article will assist ophthalmologists in accurately diagnosing anterior uveitis, improving the quality of care rendered to patients with anterior uveitis, minimizing the adverse effects of anterior uveitis, developing a decision-making strategy for management of patients at risk of permanent visual loss from anterior uveitis, informing and educating patients and other healthcare practitioners about the visual complications, risk factors, and treatment options associated with anterior uveitis.

  8. Visual agnosia.

    Science.gov (United States)

    Álvarez, R; Masjuan, J

    2016-03-01

    Visual agnosia is defined as an impairment of object recognition, in the absence of visual acuity or cognitive dysfunction that would explain this impairment. This condition is caused by lesions in the visual association cortex, sparing primary visual cortex. There are 2 main pathways that process visual information: the ventral stream, tasked with object recognition, and the dorsal stream, in charge of locating objects in space. Visual agnosia can therefore be divided into 2 major groups depending on which of the two streams is damaged. The aim of this article is to conduct a narrative review of the various visual agnosia syndromes, including recent developments in a number of these syndromes.

  9. A novel mouse model of tuberous sclerosis complex (TSC): eye-specific Tsc1-ablation disrupts visual-pathway development.

    Science.gov (United States)

    Jones, Iwan; Hägglund, Anna-Carin; Törnqvist, Gunilla; Nord, Christoffer; Ahlgren, Ulf; Carlsson, Leif

    2015-12-01

    Tuberous sclerosis complex (TSC) is an autosomal dominant syndrome that is best characterised by neurodevelopmental deficits and the presence of benign tumours (called hamartomas) in affected organs. This multi-organ disorder results from inactivating point mutations in either the TSC1 or the TSC2 genes and consequent activation of the canonical mammalian target of rapamycin complex 1 signalling (mTORC1) pathway. Because lesions to the eye are central to TSC diagnosis, we report here the generation and characterisation of the first eye-specific TSC mouse model. We demonstrate that conditional ablation of Tsc1 in eye-committed progenitor cells leads to the accelerated differentiation and subsequent ectopic radial migration of retinal ganglion cells. This results in an increase in retinal ganglion cell apoptosis and consequent regionalised axonal loss within the optic nerve and topographical changes to the contra- and ipsilateral input within the dorsal lateral geniculate nucleus. Eyes from adult mice exhibit aberrant retinal architecture and display all the classic neuropathological hallmarks of TSC, including an increase in organ and cell size, ring heterotopias, hamartomas with retinal detachment, and lamination defects. Our results provide the first major insight into the molecular etiology of TSC within the developing eye and demonstrate a pivotal role for Tsc1 in regulating various aspects of visual-pathway development. Our novel mouse model therefore provides a valuable resource for future studies concerning the molecular mechanisms underlying TSC and also as a platform to evaluate new therapeutic approaches for the treatment of this multi-organ disorder.

  10. A novel mouse model of tuberous sclerosis complex (TSC: eye-specific Tsc1-ablation disrupts visual-pathway development

    Directory of Open Access Journals (Sweden)

    Iwan Jones

    2015-12-01

    Full Text Available Tuberous sclerosis complex (TSC is an autosomal dominant syndrome that is best characterised by neurodevelopmental deficits and the presence of benign tumours (called hamartomas in affected organs. This multi-organ disorder results from inactivating point mutations in either the TSC1 or the TSC2 genes and consequent activation of the canonical mammalian target of rapamycin complex 1 signalling (mTORC1 pathway. Because lesions to the eye are central to TSC diagnosis, we report here the generation and characterisation of the first eye-specific TSC mouse model. We demonstrate that conditional ablation of Tsc1 in eye-committed progenitor cells leads to the accelerated differentiation and subsequent ectopic radial migration of retinal ganglion cells. This results in an increase in retinal ganglion cell apoptosis and consequent regionalised axonal loss within the optic nerve and topographical changes to the contra- and ipsilateral input within the dorsal lateral geniculate nucleus. Eyes from adult mice exhibit aberrant retinal architecture and display all the classic neuropathological hallmarks of TSC, including an increase in organ and cell size, ring heterotopias, hamartomas with retinal detachment, and lamination defects. Our results provide the first major insight into the molecular etiology of TSC within the developing eye and demonstrate a pivotal role for Tsc1 in regulating various aspects of visual-pathway development. Our novel mouse model therefore provides a valuable resource for future studies concerning the molecular mechanisms underlying TSC and also as a platform to evaluate new therapeutic approaches for the treatment of this multi-organ disorder.

  11. A novel mouse model of tuberous sclerosis complex (TSC): eye-specific Tsc1-ablation disrupts visual-pathway development

    Science.gov (United States)

    Jones, Iwan; Hägglund, Anna-Carin; Törnqvist, Gunilla; Nord, Christoffer; Ahlgren, Ulf; Carlsson, Leif

    2015-01-01

    ABSTRACT Tuberous sclerosis complex (TSC) is an autosomal dominant syndrome that is best characterised by neurodevelopmental deficits and the presence of benign tumours (called hamartomas) in affected organs. This multi-organ disorder results from inactivating point mutations in either the TSC1 or the TSC2 genes and consequent activation of the canonical mammalian target of rapamycin complex 1 signalling (mTORC1) pathway. Because lesions to the eye are central to TSC diagnosis, we report here the generation and characterisation of the first eye-specific TSC mouse model. We demonstrate that conditional ablation of Tsc1 in eye-committed progenitor cells leads to the accelerated differentiation and subsequent ectopic radial migration of retinal ganglion cells. This results in an increase in retinal ganglion cell apoptosis and consequent regionalised axonal loss within the optic nerve and topographical changes to the contra- and ipsilateral input within the dorsal lateral geniculate nucleus. Eyes from adult mice exhibit aberrant retinal architecture and display all the classic neuropathological hallmarks of TSC, including an increase in organ and cell size, ring heterotopias, hamartomas with retinal detachment, and lamination defects. Our results provide the first major insight into the molecular etiology of TSC within the developing eye and demonstrate a pivotal role for Tsc1 in regulating various aspects of visual-pathway development. Our novel mouse model therefore provides a valuable resource for future studies concerning the molecular mechanisms underlying TSC and also as a platform to evaluate new therapeutic approaches for the treatment of this multi-organ disorder. PMID:26449264

  12. Neurofilament protein is differentially distributed in subpopulations of corticocortical projection neurons in the macaque monkey visual pathways

    Science.gov (United States)

    Hof, P. R.; Ungerleider, L. G.; Webster, M. J.; Gattass, R.; Adams, M. M.; Sailstad, C. A.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

    1996-01-01

    Previous studies of the primate cerebral cortex have shown that neurofilament protein is present in pyramidal neuron subpopulations displaying specific regional and laminar distribution patterns. In order to characterize further the neurochemical phenotype of the neurons furnishing feedforward and feedback pathways in the visual cortex of the macaque monkey, we performed an analysis of the distribution of neurofilament protein in corticocortical projection neurons in areas V1, V2, V3, V3A, V4, and MT. Injections of the retrogradely transported dyes Fast Blue and Diamidino Yellow were placed within areas V4 and MT, or in areas V1 and V2, in 14 adult rhesus monkeys, and the brains of these animals were processed for immunohistochemistry with an antibody to nonphosphorylated epitopes of the medium and heavy molecular weight subunits of the neurofilament protein. Overall, there was a higher proportion of neurons projecting from areas V1, V2, V3, and V3A to area MT that were neurofilament protein-immunoreactive (57-100%), than to area V4 (25-36%). In contrast, feedback projections from areas MT, V4, and V3 exhibited a more consistent proportion of neurofilament protein-containing neurons (70-80%), regardless of their target areas (V1 or V2). In addition, the vast majority of feedback neurons projecting to areas V1 and V2 were located in layers V and VI in areas V4 and MT, while they were observed in both supragranular and infragranular layers in area V3. The laminar distribution of feedforward projecting neurons was heterogeneous. In area V1, Meynert and layer IVB cells were found to project to area MT, while neurons projecting to area V4 were particularly dense in layer III within the foveal representation. In area V2, almost all neurons projecting to areas MT or V4 were located in layer III, whereas they were found in both layers II-III and V-VI in areas V3 and V3A. These results suggest that neurofilament protein identifies particular subpopulations of

  13. Dose-Response Modeling of the Visual Pathway Tolerance to Single-Fraction and Hypofractionated Stereotactic Radiosurgery.

    Science.gov (United States)

    Hiniker, Susan M; Modlin, Leslie A; Choi, Clara Y; Atalar, Banu; Seiger, Kira; Binkley, Michael S; Harris, Jeremy P; Liao, Yaping Joyce; Fischbein, Nancy; Wang, Lei; Ho, Anthony; Lo, Anthony; Chang, Steven D; Harsh, Griffith R; Gibbs, Iris C; Hancock, Steven L; Li, Gordon; Adler, John R; Soltys, Scott G

    2016-04-01

    Patients with tumors adjacent to the optic nerves and chiasm are frequently not candidates for single-fraction stereotactic radiosurgery (SRS) due to concern for radiation-induced optic neuropathy. However, these patients have been successfully treated with hypofractionated SRS over 2-5 days, though dose constraints have not yet been well defined. We reviewed the literature on optic tolerance to radiation and constructed a dose-response model for visual pathway tolerance to SRS delivered in 1-5 fractions. We analyzed optic nerve and chiasm dose-volume histogram (DVH) data from perioptic tumors, defined as those within 3mm of the optic nerves or chiasm, treated with SRS from 2000-2013 at our institution. Tumors with subsequent local progression were excluded from the primary analysis of vision outcome. A total of 262 evaluable cases (26 with malignant and 236 with benign tumors) with visual field and clinical outcomes were analyzed. Median patient follow-up was 37 months (range: 2-142 months). The median number of fractions was 3 (1 fraction n = 47, 2 fraction n = 28, 3 fraction n = 111, 4 fraction n = 10, and 5 fraction n = 66); doses were converted to 3-fraction equivalent doses with the linear quadratic model using α/β = 2Gy prior to modeling. Optic structure dose parameters analyzed included Dmin, Dmedian, Dmean, Dmax, V30Gy, V25Gy, V20Gy, V15Gy, V10Gy, V5Gy, D50%, D10%, D5%, D1%, D1cc, D0.50cc, D0.25cc, D0.20cc, D0.10cc, D0.05cc, D0.03cc. From the plan DVHs, a maximum-likelihood parameter fitting of the probit dose-response model was performed using DVH Evaluator software. The 68% CIs, corresponding to one standard deviation, were calculated using the profile likelihood method. Of the 262 analyzed, 2 (0.8%) patients experienced common terminology criteria for adverse events grade 4 vision loss in one eye, defined as vision of 20/200 or worse in the affected eye. One of these patients had received 2 previous courses of radiotherapy to the optic structures

  14. Emphasize the importance of study on treatment and visual restoration related to impairment of retro-chiasmal visual pathway%重视后视路损伤的治疗与视功能的康复

    Institute of Scientific and Technical Information of China (English)

    魏世辉; 张晓君

    2011-01-01

    累及后视路的脑卒中、脑肿瘤及脑外伤所导致同向偏盲性视野缺损在临床上很常见.尽管部分患者在损伤早期视野有部分改善,但是仍严重影响患者日常生活工作能力.国外系列研究显示以“残余视觉理论”和“脑塑形”为基础的视觉重建治疗可以通过扩大患者视野改善视功能.尽管目前国际上对视觉重建治疗效果和机制还存在较大争论,但由于视路损害所致视功能损伤的普遍危害性,以及目前缺乏其他有效的治疗手段,在国内开展多学科合作、大样本的临床病例对照研究,客观评价各种治疗康复手段的效果,对于提高后视路损伤患者的日常生活和工作能力有重要意义.%Homonymous visual field defect which is usually caused by stroke,brain tumor and trauma,is common.In spite of partial spontaneous recovery,homonymous hemianopia still causes serious disability.Visual restoration therapy (VRT) based on the residual visual capability and brain plasticity theory was reported effectively enlarged visual field caused by impairment of visual pathway.Controversy still exits on the efficacy of these procedures.However,due to the high prevalence and poor outcome of visual pathway impairment,it is important to initiate multiple disciplinary co-operative study on VRT and other procedures for visual function rehabilitation to improve life quality of patients with retro-chiasmal visual pathway impairment.

  15. Positioning of anterior teeth in removable dentures

    Directory of Open Access Journals (Sweden)

    Strajnić Ljiljana

    2002-01-01

    Full Text Available Introduction The aim of this paper was to present methods of placement of artificial anterior teeth in edentulous individuals. The following review takes account of the majority of papers published during the last 100 years. The review has been divided into sections regarding the method used to determine the position of artificial anterior teeth. Geometric aspect Gysi (1895-1920 produced the first scientific theory about the position of artificial anterior teeth. Physiognomic theory The aim of this theory is to find the most natural position for artificial anterior teeth for each individual. Camper's "face angle" as a physiognomic criterion, has been introduced in papers of Wehrli (1961, Marxhors (1966, Tanzer (1968, Lombardi (1973. Esthetic aspect Important names in the field of dental esthetics are: Schön and Singer (1961, Arnheim (1965, Krajiček (1969, Tanzer (1968, Lombardi (1973, Goldstein (1976. They have introduced principles of visual aspects for selection of contours, dimension and position of artificial anterior teeth. Constitution aspect Flagg (1880, Williams (1913 and Hrauf (1957, 1958, have considered body constitution and individual characteristics regarding position of artificial anterior teeth. Physiological theory In 1971, Marxhors pointed to the fact that the position of artificial teeth corresponds with the function of the surrounding soft tissue and from the aspect of physiognomy as well. Phonetic aspect According to Silverman (1962 artificial anterior teeth are nearest when we pronounce the sound "S". Cephalometrical research Rayson (1970, Watson (1989, Strajnić Lj. (1999, Bassi F. (2001 have presented cephalometric radiographic analyses of natural anterior teeth compared with cephalometric radiographic analyses of artificial anterior teeth. A review of dental literature shows several factors suggesting modalities which should determine the position of artificial anterior teeth. Numerous methods have been designed for

  16. Relationship between optical coherence tomography and electrophysiology of the visual pathway in non-optic neuritis eyes of multiple sclerosis patients.

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    Prema Sriram

    Full Text Available PURPOSE: Loss of retinal ganglion cells in in non-optic neuritis eyes of Multiple Sclerosis patients (MS-NON has recently been demonstrated. However, the pathological basis of this loss at present is not clear. Therefore, the aim of the current study was to investigate associations of clinical (high and low contrast visual acuity and electrophysiological (electroretinogram and multifocal Visual Evoked Potentials measures of the visual pathway with neuronal and axonal loss of RGC in order to better understand the nature of this loss. METHODS: Sixty-two patients with relapsing remitting multiple sclerosis with no previous history of optic neuritis in at least one eye were enrolled. All patients underwent a detailed ophthalmological examination in addition to low contrast visual acuity, Optical Coherence Tomography, full field electroretinogram (ERG and multifocal visual evoked potentials (mfVEP. RESULTS: There was significant reduction of ganglion cell layer thickness, and total and temporal retinal nerve fibre layer (RNFL thickness (p<0.0001, 0.002 and 0.0002 respectively. Multifocal VEP also demonstrated significant amplitude reduction and latency delay (p<0.0001 for both. Ganglion cell layer thickness, total and temporal RNFL thickness inversely correlated with mfVEP latency (r = -0.48, p<0.0001 respectively; r = -0.53, p<0.0001 and r = -0.59, p<0.0001 respectively. Ganglion cell layer thickness, total and temporal RNFL thickness also inversely correlated with the photopic b-wave latency (r = -0.35, p = 0.01; r = -0.33, p = 0.025; r = -0.36, p = 0.008 respectively. Multivariate linear regression model demonstrated that while both factors were significantly associated with RGC axonal and neuronal loss, the estimated predictive power of the posterior visual pathway damage was considerably larger compare to retinal dysfunction. CONCLUSION: The results of our study demonstrated significant association of RGC

  17. β-Hydroxybutyric Sodium Salt Inhibition of Growth Hormone and Prolactin Secretion via the cAMP/PKA/CREB and AMPK Signaling Pathways in Dairy Cow Anterior Pituitary Cells

    Directory of Open Access Journals (Sweden)

    Shou-Peng Fu

    2015-02-01

    Full Text Available β-hydroxybutyric acid (BHBA regulates the synthesis and secretion of growth hormone (GH and prolactin (PRL, but its mechanism is unknown. In this study, we detected the effects of BHBA on the activities of G protein signaling pathways, AMPK-α activity, GH, and PRL gene transcription, and GH and PRL secretion in dairy cow anterior pituitary cells (DCAPCs. The results showed that BHBA decreased intracellular cAMP levels and a subsequent reduction in protein kinase A (PKA activity. Inhibition of PKA activity reduced cAMP response element-binding protein (CREB phosphorylation, thereby inhibiting GH and PRL transcription and secretion. The effects of BHBA were attenuated by a specific Gαi inhibitor, pertussis toxin (PTX. In addition, intracellular BHBA uptake mediated by monocarboxylate transporter 1 (MCT1 could trigger AMPK signaling and result in the decrease in GH and PRL mRNA translation in DCAPCs cultured under low-glucose and non-glucose condition when compared with the high-glucose group. This study identifies a biochemical mechanism for the regulatory action of BHBA on GH and PRL gene transcription, translation, and secretion in DCAPCs, which may be one of the factors that regulate pituitary function during the transition period in dairy cows.

  18. Ability of Mn2+ to Permeate the Eye and Availability of Manganese-enhanced Magnetic Resonance Imaging for Visual Pathway Imaging via Topical Administration

    Institute of Scientific and Technical Information of China (English)

    Yao Chen; Chun-Yan Shi; Ying Li; Yun-Tao Hu; Hong-Bin Han; Xiao-Dong Sun; Satyajeet S Salvi

    2016-01-01

    Background:Manganese-enhanced magnetic resonance imaging (MEMRI) for visual pathway imaging via topical administration requires further research.This study investigated the permeability of the corneal epithelium and corneal toxicity after topical administration of Mn2+ to understand the applicability of MEMRI.Methods:Forty New Zealand rabbits were divided into 0.05 mol/L,0.10 mol/L,and 0.20 mol/L groups as well as a control group (n =10 in each group).Each group was further subdivided into epithelium-removed and epithelium-intact subgroups (n =5 in each subgroup).Rabbits were given 8 drops of MnC12 in 5 min intervals.The Mn2+ concentrations in the aqueous and vitreous humors were analyzed using inductively coupled plasma-mass spectrometry at different time points.MEMRI scanning was carried out to image the visual pathway after 24 h.The corneal toxicity of Mn2+ was evaluated with corneal imaging and pathology slices.Results:Between the aqueous and vitreous humors,there was a 10 h lag for the peak Mn2+ concentration times.The intraocular Mn2+ concentration increased with the concentration gradients of Mn2+ and was higher in the epithelium-removed subgroup than that in the epithelium-intact subgroup.The enhancement of the visual pathway was achieved in the 0.10 mol/L and 0.20 mol/L epithelium-removed subgroups.The corresponding peak concentrations of Mn2+ were 5087 ± 666 ng/ml,22920 ± 1188 ng/ml in the aqueous humor and 884 ± 78 ng/ml,2556 ± 492 ng/ml in the vitreous body,respectively.Corneal injury was evident in the epithelium-removed and 0.20 mol/L epithelium-intact subgroups.Conclusions:The corneal epithelium is a barrier to Mn2+,and the iris and lens septum might be another intraocular barrier to the permeation of Mn2+.An elevated Mn2+ concentration contributes to the increased permeation of Mn2+,higher MEMRI signal,and corneal toxicity.The enhancement of the visual pathway requires an effective Mn2+ concentration in the vitreous body.

  19. CONGENITAL ANTERIOR TIBIOFEMURAL SUBLUXATION

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    A. Shahla

    2008-06-01

    Full Text Available Congenital anterior tibiofemoral subluxation is an extremely rare disorder. All reported cases accompanied by other abnormalities and syndromes. A 16-year-old high school girl referred to us with bilateral anterior tibiofemoral subluxation as the knees were extended and reduced at more than 30 degrees flexion. Deformities were due to tightness of the iliotibial band and biceps femuris muscles and corrected by surgical release. Associated disorders included bilateral anterior shoulders dislocation, short metacarpals and metatarsals, and right calcaneuvalgus deformity.

  20. Peripheral sounds rapidly activate visual cortex: evidence from electrocorticography.

    Science.gov (United States)

    Brang, David; Towle, Vernon L; Suzuki, Satoru; Hillyard, Steven A; Di Tusa, Senneca; Dai, Zhongtian; Tao, James; Wu, Shasha; Grabowecky, Marcia

    2015-11-01

    Neurophysiological studies with animals suggest that sounds modulate activity in primary visual cortex in the presence of concurrent visual stimulation. Noninvasive neuroimaging studies in humans have similarly shown that sounds modulate activity in visual areas even in the absence of visual stimuli or visual task demands. However, the spatial and temporal limitations of these noninvasive methods prevent the determination of how rapidly sounds activate early visual cortex and what information about the sounds is relayed there. Using spatially and temporally precise measures of local synaptic activity acquired from depth electrodes in humans, we demonstrate that peripherally presented sounds evoke activity in the anterior portion of the contralateral, but not ipsilateral, calcarine sulcus within 28 ms of sound onset. These results suggest that auditory stimuli rapidly evoke spatially specific activity in visual cortex even in the absence of concurrent visual stimulation or visual task demands. This rapid auditory-evoked activation of primary visual cortex is likely to be mediated by subcortical pathways or direct cortical projections from auditory to visual areas.

  1. Anterior cingulate integrity: executive and neuropsychiatric features in Parkinson's disease.

    Science.gov (United States)

    Lewis, Simon J G; Shine, James M; Duffy, Shantel; Halliday, Glenda; Naismith, Sharon L

    2012-09-01

    Patients with advanced Parkinson's disease (PD) commonly suffer with significant executive dysfunction and concomitant visual hallucinations. Although the underlying pathophysiology remains poorly understood, numerous studies have highlighted the strong association between these neuropsychiatric features, suggesting common neural pathways. Although previous neuroimaging studies have identified widespread volume loss across a number of cortical regions, to date, no studies have utilized proton magnetic resonance spectroscopy to provide insights into how neurometabolic changes may relate to such symptoms. Twenty patients with PD and 20 healthy controls underwent spectroscopy to determine the N-acetyl aspartate/creatine (NAA/Cr) ratio, which reflects the degree of neuronal integrity in neurodegenerative diseases. Voxels were obtained from the anterior cingulate cortex (ACC), an area critical for a wide range of executive mechanisms as well as from a control volume in the posterior cingulate cortex (PCC). Compared to controls, patients with PD had lower NAA/Cr ratios in the ACC. In turn, lower NAA/Cr ratios significantly correlated with poorer executive function on tasks of attentional set-shifting and response inhibition, as well as more-severe psychotic symptoms and poorer performance on the Bistable Percept Paradigm, a neuropsychological probe of visual hallucinations. NAA/Cr ratios were significantly lower in hallucinators, compared to nonhallucinators, within the ACC, but did not differ in the PCC. These results suggest that loss of neuronal integrity within the ACC plays an important role in the pathophysiology underlying executive functioning and visual hallucinations in PD. © 2012 Movement Disorder Society.

  2. Afferent Visual Pathway Affection in Patients with PMP22 Deletion-Related Hereditary Neuropathy with Liability to Pressure Palsies

    Science.gov (United States)

    Rinnenthal, Jan Leo; Zimmermann, Hanna; Mikolajczak, Janine; Oberwahrenbrock, Timm; Papazoglou, Sebastian; Pfüller, Caspar F.; Schinzel, Johann; Tackenberg, Björn; Paul, Friedemann; Hahn, Katrin; Bellmann-Strobl, Judith

    2016-01-01

    Background The PMP22 gene encodes a protein integral to peripheral myelin. Its deletion leads to hereditary neuropathy with liability to pressure palsies (HNPP). PMP22 is not expressed in the adult central nervous system, but previous studies suggest a role in CNS myelin development. The objective of this study was to identify potential structural and functional alterations in the afferent visual system in HNPP patients. Methods Twenty HNPP patients and 18 matched healthy controls (HC) were recruited in a cross-sectional study. Participants underwent neurological examination including visual acuity, visual evoked potential (VEP) examination, optical coherence tomography (OCT), and magnetic resonance imaging with calculation of brain atrophy, regarding grey and white matter, and voxel based morphometry (VBM), in addition answered the National Eye Institute’s 39-item Visual Functioning Questionnaire (NEI-VFQ). Thirteen patients and 6 HC were additionally examined with magnetic resonance spectroscopy (MRS). Results All patients had normal visual acuity, but reported reduced peripheral vision in comparison to HC in the NEI-VFQ (p = 0.036). VEP latency was prolonged in patients (P100 = 103.7±5.7 ms) in comparison to healthy subjects (P100 = 99.7±4.2 ms, p = 0.007). In OCT, peripapillary retinal nerve fiber layer thickness RNFL was decreased in the nasal sector (90.0±15.5 vs. 101.8±16.5, p = 0.013), and lower nasal sector RNFL correlated with prolonged VEP latency (Rho = -0.405, p = 0.012). MRS revealed reduced tNAA (731.4±45.4 vs. 814.9±62.1, p = 0.017) and tCr (373.8±22.2 vs. 418.7±31.1, p = 0.002) in the visual cortex in patients vs. HC. Whole brain volume, grey and white matter volume, VBM and metabolites in a MRS sensory cortex control voxel did not differ significantly between patients and HC. Conclusion PMP22 deletion leads to functional, metabolic and macro-structural alterations in the afferent visual system of HNPP patients. Our data suggest a

  3. Anterior chest wall examination reviewed

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    F. Trotta

    2011-09-01

    Full Text Available Anterior chest wall involvement is not infrequently observed within inflammatory arthropaties, particularly if one considers seronegative spondiloarthritides and SAPHO syndrome. Physical examination is unreliable and conventional X-rays analysis is an unsatisfactory tool during diagnostic work-up of this region. Scintigraphic techniques yield informations both on the activity and on the anatomical extent of the disease while computerized tomography visualize the elementary lesions, such as erosions, which characterize the process. Moreover, when available, magnetic resonance imaging couple the ability to finely visualize such lesions with the possibility to show early alterations and to characterize the “activity” of the disease, presenting itself as a powerful tool both for diagnosis and follow-up. This review briefly shows the applications of imaging techniques for the evaluation of the anterior chest wall focusing on what has been done in the SAPHO syndrome which can be considered prototypical for this regional involvement since it is the osteo-articular target mainly affected by the disease.

  4. Visual outcome after phacoemulsification with intraocular lens implantation in patients with anterior lenticonus due to Alport syndrome%超声乳化联合IOL植入治疗前圆锥晶状体伴有Alport综合征的视觉效果

    Institute of Scientific and Technical Information of China (English)

    Mohammad Ali Zare; Mohammad Taher Rajabi; Syed Jafar Oskouee; Mohammad Nili

    2006-01-01

    · AIM: We describe visual improvement after phacoemulsification with intraocular lens (IOL) implantation in 7 eyes with anterior lenticonus secondary to Alport syndrome.· METHODS: 7 eyes from 4 patients with Alport syndrome underwent phacoemulsification with IOL implantation due to anterior lenticonus.· RESULTS: All of the patients resumed excellent visual acuity after surgery.· CONCLUSION: We recommend the phacoemulsification with IOL implantation as a safe procedure in anterior lenticonus due to Alport syndrome.%目的:观察超声乳化联合IOL植入治疗7眼前圆锥晶状体伴有Alport综合征患者的手术效果.方法:Alport综合征患者4例,7眼因前圆锥晶状体行超声乳化联合IOL植入手术.结果:所有患者的术后视力均有明显提高.结论:我们认为对于前圆锥晶状体伴有Alport综合征患者采用超声乳化联合IOL植入手术治疗,是一种安全的疗法.

  5. Some points associated with the diagnosis and treatment for posterior visual pathway diseases%后部视路疾病诊治中的几个问题

    Institute of Scientific and Technical Information of China (English)

    邱怀雨; 魏世辉

    2011-01-01

    The impairment of posterior visual pathway, caused by cerebrovascular disorder, brain tumor or injury, is frequently occurred in clinic. The homonymous hemianopsia or quadrantanopsia presents in most of those patients, which are usually neglected by eye doctors for a long time. Recently, with the development of the diffusion tenser imaging (DTI) and functional magnetic resonance imaging (fMRl), it can be diagnosised more easily. We suggest that it should be treated with proper medication to decrease primary and secondary impairments of visual pathway in acute stage combined with visual restoration training in late stage.%脑血管疾病、脑肿瘤及脑外伤所导致的后视路疾病在临床上很常见,多表现为同侧偏盲或象限性盲,在国内眼科界对这类疾病的眼部表现缺乏应有的重视.弥散张量成像(diffusion tenser imaging,DTI)、功能磁共振成像(functional magnetic resonance imaging,fMRI)等影像学新技术的出现为后视路疾病的诊断提供了新的工具.对后视路疾病患者除了必要的手术治疗外,早期给予药物干预,减少原发及继发性视路损伤,稳定期给予视觉康复治疗,从而在最大程度上改善这类患者的视觉质量.(眼科,2011,20:361-363)

  6. Autoimmunity in visual loss.

    Science.gov (United States)

    Petzold, Axel; Wong, Sui; Plant, Gordon T

    2016-01-01

    There are a number of autoimmune disorders which can affect visual function. There are a very large number of mechanisms in the visual pathway which could potentially be the targets of autoimmune attack. In practice it is the retina and the anterior visual pathway (optic nerve and chiasm) that are recognised as being affected in autoimmune disorders. Multiple Sclerosis is one of the commonest causes of visual loss in young adults because of the frequency of attacks of optic neuritis in that condition, however the basis of the inflammation in Multiple Sclerosis and the confirmation of autoimmunity is lacking. The immune process is known to be highly unusual in that it is not systemic and confined to the CNS compartment. Previously an enigmatic partner to Multiple Sclerosis, Neuromyelitis Optica is now established to be autoimmune and two antibodies - to Aquaporin4 and to Myelin Oligodendrocyte Glycoprotein - have been implicated in the pathogenesis. The term Chronic Relapsing Inflammatory Optic Neuropathy is applied to those cases of optic neuritis which require long term immunosuppression and hence are presumed to be autoimmune but where no autoimmune pathogenesis has been confirmed. Optic neuritis occurring post-infection and post vaccination and conditions such as Systemic Lupus Erythematosus and various vasculitides may cause direct autoimmune attack to visual structures or indirect damage through occlusive vasculopathy. Chronic granulomatous disorders such as Sarcoidosis affect vision commonly by a variety of mechanisms, whether and how these are placed in the autoimmune panoply is unknown. As far as the retina is concerned Cancer Associated Retinopathy and Melanoma Associated Retinopathy are well characterised clinically but a candidate autoantibody (recoverin) is only described in the former disorder. Other, usually monophasic, focal retinal inflammatory disorders (Idiopathic Big Blind Spot Syndrome, Acute Zonal Occult Outer Retinopathy and Acute Macular

  7. A Potential VEP Biomarker for Mild Cognitive Impairment: Evidence from Selective Visual Deficit of Higher-Level Dorsal Pathway.

    Science.gov (United States)

    Yamasaki, Takao; Horie, Shizuka; Ohyagi, Yasumasa; Tanaka, Eri; Nakamura, Norimichi; Goto, Yoshinobu; Kanba, Shigenobu; Kira, Jun-Ichi; Tobimatsu, Shozo

    2016-05-23

    Visual dysfunctions are common in Alzheimer's disease (AD). Our aim was to establish a neurophysiological biomarker for amnestic mild cognitive impairment (aMCI). Visual evoked potentials (VEPs) were recorded in aMCI patients who later developed AD (n = 15) and in healthy older (n = 15) and younger controls (n = 15). Visual stimuli were optimized to separately activate lower and higher levels of the ventral and dorsal streams. We compared VEP parameters across the three groups of participants and conducted a linear correlation analysis between VEPs and data from neuropsychological tests. We then used a receiver operating characteristic (ROC) analysis to discriminate those with aMCI from those who were healthy older adults. The latency and phase of VEPs to lower-level stimuli (chromatic and achromatic gratings) were significantly affected by age but not by cognitive decline. Conversely, VEP latencies for higher-ventral (faces and kanji-words) and dorsal (kana-words and optic flow motion) stimuli were not affected by age, but they were significantly prolonged in aMCI patients. Interestingly, VEPs for higher-dorsal stimuli were related to outcomes of neuropsychological tests. Furthermore, the ROC analysis showed that the highest areas under the curve were obtained for VEP latencies in response to higher-dorsal stimuli. These results suggest aMCI-related functional impairment specific to higher-level visual processing. Further, dysfunction in the higher-level of the dorsal stream could be an early indicator of cognitive decline. Therefore, we conclude that VEPs associated with higher-level dorsal stream activity can be a sensitive biomarker for early detection of aMCI.

  8. The neural circuitry of visual artistic production and appreciation: A proposition

    Directory of Open Access Journals (Sweden)

    Ambar Chakravarty

    2012-01-01

    Full Text Available The nondominant inferior parietal lobule is probably a major "store house" of artistic creativity. The ventromedial prefrontal lobe (VMPFL is supposed to be involved in creative cognition and the dorsolateral prefrontal lobe (DLPFL in creative output. The conceptual ventral and dorsal visual system pathways likely represent the inferior and superior longitudinal fasciculi. During artistic production, conceptualization is conceived in the VMPFL and the executive part is operated through the DLFPL. The latter transfers the concept to the visual brain through the superior longitudinal fasciculus (SLF, relaying on its path to the parietal cortex. The conceptualization at VMPFL is influenced by activity from the anterior temporal lobe through the uncinate fasciculus and limbic system pathways. The final visual image formed in the visual brain is subsequently transferred back to the DLPFL through the SLF and then handed over to the motor cortex for execution. During art appreciation, the image at the visual brain is transferred to the frontal lobe through the SLF and there it is matched with emotional and memory inputs from the anterior temporal lobe transmitted through the uncinate fasiculus. Beauty is perceived at the VMPFL and transferred through the uncinate fasciculus to the hippocampo-amygdaloid complex in the anterior temporal lobe. The limbic system (Papez circuit is activated and emotion of appreciation is evoked. It is postulated that in practice the entire circuitry is activated simultaneously.

  9. A novel mouse model of tuberous sclerosis complex (TSC): eye-specific Tsc1-ablation disrupts visual-pathway development

    OpenAIRE

    2015-01-01

    ABSTRACT Tuberous sclerosis complex (TSC) is an autosomal dominant syndrome that is best characterised by neurodevelopmental deficits and the presence of benign tumours (called hamartomas) in affected organs. This multi-organ disorder results from inactivating point mutations in either the TSC1 or the TSC2 genes and consequent activation of the canonical mammalian target of rapamycin complex 1 signalling (mTORC1) pathway. Because lesions to the eye are central to TSC diagnosis, we report here...

  10. The role of the anterior commissure in callosal agenesis.

    Science.gov (United States)

    Barr, Melodie S; Corballis, Michael C

    2002-10-01

    Two individuals with callosal agenesis (J.P. and M.M.) and 10 neurologically normal participants were tested on tasks requiring interhemispheric visual integration. M.M., whose anterior commissure was within normal limits, was much worse at matching colors and letters between visual fields than within visual fields, whereas J.P., whose anterior commissure was greatly enlarged, showed no evidence of interhemispheric disconnection. This suggests that in some cases of callosal agenesis, probably a minority, an enlarged anterior commissure may compensate for the lack of the corpus callosum. Neither acallosal participant showed interhemispheric disconnection on tasks requiring integration of location and orientation, however, suggesting that the anterior commissure plays no role in such tasks. These tasks may depend on subcortical commissures, such as the intertectal commissure.

  11. Anterior Cruciate Ligament (ACL) Injuries

    Science.gov (United States)

    ... Week of Healthy Breakfasts Shyness Anterior Cruciate Ligament (ACL) Injuries KidsHealth > For Teens > Anterior Cruciate Ligament (ACL) ... and Recovery Coping With an ACL Injury About ACL Injuries A torn anterior cruciate ligament (ACL) is ...

  12. Applying Transcranial Magnetic Stimulation (TMS) Over the Dorsal Visual Pathway Induces Schizophrenia-like Disruption of Perceptual Closure.

    Science.gov (United States)

    Amiaz, Revital; Vainiger, Dana; Gershon, Ari A; Weiser, Mark; Lavidor, Michal; Javitt, Daniel C

    2016-07-01

    Perceptual closure ability is postulated to depend upon rapid transmission of magnocellular information to prefrontal cortex via the dorsal stream. In contrast, illusory contour processing requires only local interactions within primary and ventral stream visual regions, such as lateral occipital complex. Schizophrenia is associated with deficits in perceptual closure versus illusory contours processing that is hypothesized to reflect impaired magnocellular/dorsal stream. Perceptual closure and illusory contours performance was evaluated in separate groups of 12 healthy volunteers during no TMS, and during repetitive 10 Hz rTMS stimulation over dorsal stream or vertex (TMS-vertex). Perceptual closure and illusory contours were performed in 11 schizophrenia patients, no TMS was applied in these patients. TMS effects were evaluated with repeated measures ANOVA across treatments. rTMS significantly increased perceptual closure identification thresholds, with significant difference between TMS-dorsal stream and no TMS. TMS-dorsal stream also significantly reduced perceptual closure but not illusory contours accuracy. Schizophrenia patients showed increased perceptual closure identification thresholds relative to controls in the no TMS condition, but similar to controls in the TMS-dorsal stream condition. Conclusions of this study are that magnocellular/dorsal stream input is critical for perceptual closure but not illusory contours performance, supporting both trickledown theories of normal perceptual closure function, and magnocellular/dorsal stream theories of visual dysfunction in schizophrenia.

  13. Anterior cervical plating

    Directory of Open Access Journals (Sweden)

    Gonugunta V

    2005-01-01

    Full Text Available Although anterior cervical instrumentation was initially used in cervical trauma, because of obvious benefits, indications for its use have been expanded over time to degenerative cases as well as tumor and infection of the cervical spine. Along with a threefold increase in incidence of cervical fusion surgery, implant designs have evolved over the last three decades. Observation of graft subsidence and phenomenon of stress shielding led to the development of the new generation dynamic anterior cervical plating systems. Anterior cervical plating does not conclusively improve clinical outcome of the patients, but certainly enhances the efficacy of autograft and allograft fusion and lessens the rate of pseudoarthrosis and kyphosis after multilevel discectomy and fusions. A review of biomechanics, surgical technique, indications, complications and results of various anterior cervical plating systems is presented here to enable clinicians to select the appropriate construct design.

  14. Factors that limit the use of flash visual evoked potentials for surgical monitoring.

    Science.gov (United States)

    Cedzich, C; Schramm, J; Mengedoht, C F; Fahlbusch, R

    1988-01-01

    A study was conducted comparing the incidence with which the N2/P2/N3 was obtained after flash VEP in 3 groups: anterior visual pathway lesions, non-tumor craniotomies and non-cranial surgery. These groups allowed evaluation of the effects of anesthesia, visual pathway lesions and craniotomy on the stability of the flash VEP. It was found that the latency was not significantly affected in the 3 groups, whereas the incidence of obtainable peaks and the amplitudes were adversely affected by anesthesia, cranial surgical manipulation and especially by the presence of a visual pathway lesion. These adverse effects were so marked that the application of flash VEP for intraoperative monitoring seems of little use.

  15. Anterior commissure versus corpus callosum: A quantitative comparison across mammals.

    Science.gov (United States)

    Ashwell, Ken W S

    2016-04-01

    Mammals rely on two major pathways to transfer information between the two hemispheres of the brain: the anterior commissure and the corpus callosum. Metatheria and monotremes rely exclusively on the anterior commissure for interhemispheric transfer between the isocortices and olfactory allocortices of each side, whereas Eutheria use a combination of the anterior commissure and an additional pathway exclusive to Eutheria, the corpus callosum. Midline cross-sectional area of the anterior commissure and corpus callosum were measured in a range of mammals from all three infraclasses and plotted against brain volume to determine how midline anterior commissure area and its size relative to the corpus callosum vary with brain size and taxon. In Metatheria, the square root of anterior commissure area rises in almost direct proportion with the cube root of brain volume (i.e. the ratio of the two is relatively constant), whereas among Eutheria the ratio of the square root of anterior commissure area to the cube root of brain volume declines slightly with increasing brain size. The total of isocortical and olfactory allocortical commissure area rises more rapidly with increasing brain volume among Eutheria than among Metatheria. This means that the midline isocortical and olfactory allocortical commissural area of metatherians with large brains (about 70 ml) is only about 50% of that among eutherians with similarly sized brains. On the other hand, isocortical and olfactory allocortical commissural area is similar in Metatheria and Eutheria at brain volumes around 1 ml. Among the Eutheria, some groups make less use of the anterior commissure pathway than do others: soricomorphs, rodents and cetaceans have smaller anterior commissures for their brain size than do afrosoricids, erinaceomorphs and proboscideans. The findings suggest that use of the anterior commissural route for isocortical commissural connections may have placed limitations on interhemispheric transfer of

  16. How Does the Hippocampal Formation Mediate Memory for Stimuli Processed by the Magnocellular and Parvocellular Visual Pathways? Evidence from the Comparison of Schizophrenia and Amnestic Mild Cognitive Impairment (aMCI)

    Science.gov (United States)

    Keri, Szabolcs; Szamosi, Andras; Benedek, Gyorgy; Kelemen, Oguz

    2012-01-01

    Paired associates learning is impaired in both schizophrenia and amnestic mild cognitive impairment (aMCI), which may reflect hippocampal pathology. In addition, schizophrenia is characterized by the dysfunction of the retino-geniculo-striatal magnocellular (M) visual pathway. The purpose of this study was to investigate the interaction between…

  17. Clinical utility and limitations of intraoperative monitoring of visual evoked potentials.

    Directory of Open Access Journals (Sweden)

    Yeda Luo

    Full Text Available During surgeries that put the visual pathway at risk of injury, continuous monitoring of the visual function is desirable. However, the intraoperative monitoring of the visual evoked potential (VEP is not yet widely used. We evaluate here the clinical utility of intraoperative VEP monitoring.We analyzed retrospectively 46 consecutive surgeries in 2011-2013. High luminance stimulating devices delivered flash stimuli on the closed eyelid during intravenous anesthesia. We monitored VEP features N75 and P100 and took patients' preoperative and postoperative visual function from patient charts. Postoperative ophthalmologic workup was performed in 25 (54% patients and preoperatively in 28 (61% patients.VEP recordings were feasible in 62 of 85 eyes (73% in 46 patients. All 23 eyes without VEP had impaired vision. During surgery, VEPs remained stable throughout surgery in 50 eyes. In 44 of these, visual function did not deteriorate and three patients (6 eyes developed hemianopia. VEP decreased transiently in 10 eyes and visual function of all was preserved. VEPs were lost permanently in 2 eyes in two patients without new postoperative visual impairment.Satisfactory intraoperative VEP monitoring was feasible in all patients except in those with severe visual impairment. Preservation of VEPs predicted preserved visual function. During resection of lesions in the visual cortex, VEP monitoring could not detect new major visual field defects due to injury in the posterior visual pathway. Intraoperative VEPs were sensitive enough to detect vascular damage during aneurysm clipping and mechanical manipulation of the anterior visual pathway in an early reversible stage. Intraoperative VEP monitoring influenced surgical decisions in selected patients and proved to be a useful supplement to the toolbox of intraoperative neurophysiological monitoring.

  18. Combined operative technique with anterior surgical approach and video-assisted thoracoscopic surgical lobectomy for anterior superior sulcus tumours.

    Science.gov (United States)

    Yokoyama, Yuhei; Chen, Fengshi; Aoyama, Akihiro; Sato, Toshihiko; Date, Hiroshi

    2014-11-01

    Video-assisted thoracoscopic surgery (VATS) has been widely used, but surgical resections of superior sulcus tumours remain challenging because of their anatomical location. For such cases, less-invasive procedures, such as the anterior transcervical-thoracic and transmanubrial approaches, have been widely performed because of their excellent visualization of the subclavian vessels. Recently, a combined operative technique with an anterior surgical approach and VATS for anterior superior sulcus tumours has been introduced. Herein, we report three cases of anterior superior sulcus tumours successfully resected by surgical approaches combined with a VATS-based lobectomy. In all cases, operability was confirmed by VATS, and upper lobectomies with hilar and mediastinal lymph node dissections were performed. Subsequently, dissections of the anterior inlet of the tumours were performed using the transmanubrial approach in two patients and the anterior trans-cervical-thoracic approach in one patient. Both approaches provided excellent access to the anterior inlet of the tumour and exposure of the subclavian vessels, resulting in radical resection of the tumour with concomitant resection of the surrounding anatomical structures, including the chest wall and vessels. In conclusion, VATS lobectomy combined with the anterior surgical approach might be an excellent procedure for the resection of anterior superior sulcus tumours.

  19. Autoradiographic visualization of angiotensin-converting enzyme in rat brain with (/sup 3/H)captopril: localization to a striatonigral pathway

    Energy Technology Data Exchange (ETDEWEB)

    Strittmatter, S.M.; Lo, M.M.S.; Javitch, J.A.; Snyder, S.H.

    1984-03-01

    The authors have visualized angiotensin-converting enzyme (ACE; dipeptidyl carboxypeptidase, peptidylpeptide hydrolase, EC 3.4.15.1) in rat brain by in vitro (/sup 3/H)captopril autoradiography. (/sup 3/H)Captopril binding to brain slices displays a high affinity (K/sub d/ = 1.8 x 10/sup -9/ M) and a pharmacological profile similar to that of ACE activity. Very high densities of (/sup 3/H)captopril binding were found in the choroid plexus and the subfornical organ. High densities were present in the caudate putamen and substantia nigra, zona reticulata. Moderate levels were found in the entopeduncular nucleus, globus pallidus, and median eminence of the hypothalamus. Lower levels were detectable in the supraoptic and paraventricular nuclei of the hypothalamus, the media habenula, the median preoptic area, and the locus coeruleus. Injection of ibotenic acid or colchicine into the caudate putamen decreased (/sup 3/H)captopril-associated autoradiographic grains by 85% in the ipsilateral caudate putamen and by > 50% in the ipsilateral substantia nigra. Thus, ACE in the substantia nigra is located on presynaptic terminals of axons originating from the caudate putamen, and ACE in the caudate putamen is situated in neuronal perikarya or at the terminals of striatal interneurons. The lack of effect of similar injections into the substantia nigra confirmed that the caudate putamen injections did not cause trans-synaptic changes. The presence of (/sup 3/H)captopril binding is consistent with an ACE-mediated production of angiotensin II in some brain regions. Although (/sup 3/H)captopril autoradiography reveals ACE in a striatonigral pathway, there is no evidence for angiotensin II involvement in such a neuronal pathway. 26 references, 4 figures, 2 tables.

  20. Late spontaneous resolution of a double anterior chamber post deep anterior lamellar keratoplasty

    Directory of Open Access Journals (Sweden)

    Andrea Passani

    2017-01-01

    Full Text Available A 31-year-old healthy male underwent deep anterior lamellar keratoplasty with big-bubble technique for treatment of keratoconus in his right eye. One week after surgery, he presented with detachment of the endothelium-Descemet complex with formation of a double anterior chamber, despite the apparent absence of an intraoperative Descemet membrane rupture. A subsequent intervention with the intent to relocate the corneal graft button was not effective, because the detachment appeared again one day later. The authors hypothesized that, at the time of the stromal dissection with big bubble technique, a small amount of air penetrated into the anterior chamber, creating a false pathway through the trabecular meshwork. The aqueous humor then penetrated the graft flowing through the false pathway, causing the endothelium-Descemet detachment. The persistence of that pathway, even after the intervention of graft repositioning, caused the failure of the latter procedure and persistence of the double chamber. We decided to wait and observe. The double anterior chamber spontaneously resolved in approximately three months.

  1. Nonnecrotizing anterior scleritis mimicking orbital inflammatory disease

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    Lynch MC

    2013-08-01

    Full Text Available Michelle Chen Lynch,1 Andrew B Mick21Optometry Clinic, Ocala West Veterans Affairs Specialty Clinic, Ocala, FL, USA; 2Eye Clinic, San Francisco VA Medical Center, San Francisco, CA, USABackground: Anterior scleritis is an uncommon form of ocular inflammation, often associated with coexisting autoimmune disease. With early recognition and aggressive systemic therapy, prognosis for resolution is good. The diagnosis of underlying autoimmune disease involves a multidisciplinary approach.Case report: A 42-year-old African American female presented to the Eye Clinic at the San Francisco Veteran Affairs Medical Center, with a tremendously painful left eye, worse on eye movement, with marked injection of conjunctiva. There was mild swelling of the upper eyelid. Visual acuity was unaffected, but there was a mild red cap desaturation. The posterior segment was unremarkable. The initial differential diagnoses included anterior scleritis and orbital inflammatory disease. Oral steroid treatment was initiated with rapid resolution over a few days. Orbital imaging was unremarkable, and extensive laboratory work-up was positive only for antinuclear antibodies. The patient was diagnosed with idiopathic diffuse, nonnecrotizing anterior scleritis and has been followed for over 5 years without recurrence. The rheumatology clinic monitors the patient closely, as suspicion remains for potential arthralgias including human leukocyte antigen-B27-associated arthritis, lupus-associated arthritis, seronegative rheumatoid arthritis, recurrent juvenile idiopathic arthritis, and scleroderma, based on her constitutional symptoms and clinical presentation, along with a positive anti-nuclear antibody lab result.Conclusion: Untreated anterior scleritis can progress to formation of cataracts, glaucoma, uveitis, corneal melting, and posterior segment disease with significant risk of vision loss. Patients with anterior scleritis must be aggressively treated with systemic anti

  2. Longitudial observation of dynamic changes in cortical function and white matter fibrous structure of patients with visual pathway lesions by blood oxygenation level dependent-functional magnetic resonance imaging combined with diffusion tensor imaging

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: Functional magnetic resonance imaging (fMRI) is initially used for visual cortex location.However, the application of fMRI in investigating the development of visual pathway lesions needs to be further observed.OBJECTIVE: This study is to longitudially observe the dynamic changes in cortical function and white matter fibrous structure of patients with visual pathway lesions by blood oxygenation level dependent-functional magnetic resonance imaging (BOLD-fMRI) combined with diffusion tensor imaging (DTI), and to analyze the characteristics of brain function and structural recombination at convalescent period of lesions.DESIGN: Randomized controlled observation.SETTING: Department of Radiology, the General Hospital of Nanjing Military Area Command of Chinese PLA.PARTICIPANTS: Eight patients with unilateral or bilateral visual disorder caused by visual pathway lesions,who admitted to Department of Radiology, the General Hospital of Nanjing Military Area Command of Chinese PLA from January to September 2006 were involved, and served as experimental subjects. The patients, 6 males and 2 females, were aged 16 - 67 years. They had visual disorder confirmed by clinical examination, i.e. visual pathway lesion, which was further diagnosed by MR or CT. Another 12 subjects generally matching to those patients of experimental group in gender, age and sight, who received health examination in synchronization were involved and served as controls. The subjects had no history of eye diseases. Their binocular visual acuity (or corrected visual acuity) was over 1.0. Both routine examination of ophthalmology and examination of fundus were normal. Informed consents of detected items were obtained from all the subjects.METHODS: Signa Excite HD 1.5T magnetic resonance imaging system with 16 passages (GE Company,USA) and coil with 8 passages were used; brain functional stimulus apparatus (SAV-8800. Meide Company) was used for showing experimental mission. At the early stage

  3. Neural correlates of visualizations of concrete and abstract words in preschool children: A developmental embodied approach

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    Amedeo eD'angiulli

    2015-06-01

    Full Text Available The neural correlates of visualization underlying word comprehension were examined in preschool children. On each trial, a concrete or abstract word was delivered binaurally (part 1: post-auditory visualization, followed by a four-picture array (a target plus three distractors (part 2: matching visualization. Children were to select the picture matching the word they heard in part 1. Event-Related Potentials (ERPs locked to each stimulus presentation and task interval were averaged over sets of trials of increasing word abstractness. ERP time-course during both parts of the task showed that early activity (i.e. < 300 ms was predominant in response to concrete words, while activity in response to abstract words became evident only at intermediate (i.e. 300-699 ms and late (i.e. 700-1000 ms ERP intervals. Specifically, ERP topography showed that while early activity during post-auditory visualization was linked to left temporo-parietal areas for concrete words, early activity during matching visualization occurred mostly in occipito-parietal areas for concrete words, but more anteriorly in centro-parietal areas for abstract words. In intermediate ERPs, post-auditory visualization coincided with parieto-occipital and parieto-frontal activity in response to both concrete and abstract words, while in matching visualization a parieto-central activity was common to both types of words. In the late ERPs for both types of words, the post-auditory visualization involved right-hemispheric activity following a post-anterior pathway sequence: occipital, parietal and temporal areas; conversely, matching visualization involved left-hemispheric activity following an ant-posterior pathway sequence: frontal, temporal, parietal and occipital areas. These results suggest that, similarly for concrete and abstract words, meaning in young children depends on variably complex visualization processes integrating visuo-auditory experiences and supramodal embodying

  4. Neural correlates of visualizations of concrete and abstract words in preschool children: a developmental embodied approach.

    Science.gov (United States)

    D'Angiulli, Amedeo; Griffiths, Gordon; Marmolejo-Ramos, Fernando

    2015-01-01

    The neural correlates of visualization underlying word comprehension were examined in preschool children. On each trial, a concrete or abstract word was delivered binaurally (part 1: post-auditory visualization), followed by a four-picture array (a target plus three distractors; part 2: matching visualization). Children were to select the picture matching the word they heard in part 1. Event-related potentials (ERPs) locked to each stimulus presentation and task interval were averaged over sets of trials of increasing word abstractness. ERP time-course during both parts of the task showed that early activity (i.e., words, while activity in response to abstract words became evident only at intermediate (i.e., 300-699 ms) and late (i.e., 700-1000 ms) ERP intervals. Specifically, ERP topography showed that while early activity during post-auditory visualization was linked to left temporo-parietal areas for concrete words, early activity during matching visualization occurred mostly in occipito-parietal areas for concrete words, but more anteriorly in centro-parietal areas for abstract words. In intermediate ERPs, post-auditory visualization coincided with parieto-occipital and parieto-frontal activity in response to both concrete and abstract words, while in matching visualization a parieto-central activity was common to both types of words. In the late ERPs for both types of words, the post-auditory visualization involved right-hemispheric activity following a "post-anterior" pathway sequence: occipital, parietal, and temporal areas; conversely, matching visualization involved left-hemispheric activity following an "ant-posterior" pathway sequence: frontal, temporal, parietal, and occipital areas. These results suggest that, similarly, for concrete and abstract words, meaning in young children depends on variably complex visualization processes integrating visuo-auditory experiences and supramodal embodying representations.

  5. Outcome of visual acuity after surgical removal of pituitary adenomas

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    Grković Desanka

    2013-01-01

    Full Text Available Introduction. Pituitary adenomas with suprasellar extension may produce anterior visual pathway compression, resulting in characteristic visual deficit. Surgical decompression of these structures prevents further visual deterioration and its postop­ erative recovery. Objective. The aim of this study was to investigate pre­ and postoperative visual acuity (VA in patients with pituitary ad­ enomas, and to detect the influence of prognostic factors, such as symptoms duration, degree of visual acuity reduction and tumor size in the assessment of the prognosis of postoperative visual function. Methods. We analyzed 40 consecutive patients who fulfilled three criteria: evidence of preoperative visual dysfunction, transsphenoidal or transfrontal tumor resection and hystologically verified pituitary adenoma. A visual examination was performed under standard conditions, pre and postoperatively (10 days, one month and six months after surgery. A paired t­test was used to assess the differences of pre­ and postoperative characteristics values, and the Chisquare test of independence in the assessment of the influence of prognostic factors. Results. Postoperative improvement of VA was seen in 84.61% patients (68% eyes. Eyes with preoperative mild and moderate degree of VA reduction showed improvement in 89.65% eyes in contrast to 22.60% eyes with preoperative severe reduction of VA, which was all statistically significant. Eyes in patients with tumor smaller than 20 mm had improvement of VA in 91.66% eyes, while eyes with tumor larger than 40 mm had improvement of VA in 61.11% eyes, which was statistically significant. When symptoms duration was below two years the improvement of VA was detected in 65.38% eyes as related to 50% eyes with symptoms duration exceeding two years, which was not statistically significant. Conclusion. Pituitary adenomas commonly cause visual impairment. Postoperatively the majority of patients show a distinct improvement of

  6. Anterior crucate ligament (ACL) injury

    Science.gov (United States)

    ... An anterior cruciate ligament injury is the over-stretching or tearing of the anterior cruciate ligament (ACL) ... may be injured. This is a medical emergency. Prevention Use proper techniques when playing sports or exercising. ...

  7. Comparison analysis of anterior and posterior pathways surgery for patients with multilevel cervical spondylotic myelopathy%单纯前入路与后入路治疗多节段脊髓型颈椎病的疗效对比研究

    Institute of Scientific and Technical Information of China (English)

    陈定中

    2015-01-01

    目的:比较单纯前入路与后入路治疗多节段脊髓型颈椎病( MCSM)的疗效及对患者生活质量的影响。方法收集2008年6月至2012年6月收治的140例 MCSM 患者作为研究对象。随机分为前路组70例和后路组70例。前路组给予单纯前入路手术治疗,后路组给予后入路手术治疗。比较两组患者手术状况、日本骨科协会评估(JOA)评分、视觉模拟评分(VAS),颈椎功能障碍指数(NDI)以及生活质量。结果两组患者术中出血量与症状消失时间差异无统计学意义( P >0.05),前路组手术时间显著短于后路组,其治疗后 JOA 评分显著高于后路组,差异具有统计学意义( P 均0.05),后路组 NDI 显著低于前路组,差异具有统计学意义( P <0.05)。两组患者治疗后生活质量均显著提高,后路组在活力、情绪角色与心理卫生方面的评分均显著高于前路组,差异均具有统计学意义( P <0.05)。结论单纯前路手术与后路手术治疗 MCSM 各有优势,临床上需要结合病人的实际情况做出选择以达到较好的临床获益。%Objective To compare the efficacy of anterior and posterior pathways surgery for patients with multilevel cervical spondylotic myelopathy(MCSM)and provide clinical basis for clinical therapy. Methods From June 2008 to June 2012,140 MCSM cases were collected and divided into 2 groups randomly. 70 cases were in anterior pathways group(APG)and 70 cases in posterior pathways group(PPG). The APG was treated with anterior pathways surgery and the PPG was treated with posterior pathways surgery. The surgery status,JOA score,VAS score, NDI and life quality of the 2 groups were observed and compared. Results The length of the surgery of the APG was significantly shorter than that of the PPG( P < 0. 05). The JOA score of the APG was significantly higher than that of the PPG after treatments( P < 0. 05). The VAS score of the 2 groups

  8. Facetas em dentes anteriores

    OpenAIRE

    Veloso, Helena Rafaela Lourenço Martins

    2015-01-01

    Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária A presente revisão bibliográfica aborda as facetas estéticas em dentes anteriores, pela crescente valorização de um sorriso esteticamente agradável, facto que faz com que as pessoas procurem cada vez mais alternativas de tratamento para melhorar a aparência do seu sorriso. Os dentes anteriores são decisivos na aparência estética e, c...

  9. Anterior diffuse scleritis diagnosed as conjunctivitis

    Directory of Open Access Journals (Sweden)

    K. P. Mashige

    2012-12-01

    Full Text Available This article presents a case of anterior diffuse scleritis that initially was diagnosed as conjunctivitis. Anterior diffuse scleritis (ADS is a potentially vision-threatening inflammation of the sclera whose etiology may include autoimmune and systemic conditions such as rheumatoid arthritis and tuberculosis. The signs and symptoms of ADS include pain, tearing, tenderness, redness, painful sensitivity to light and decreased visual acuity. Ocular and physical examinations including blood tests to rule out underlying causes are important. Medications such as corticosteroids, non-steroidal anti-inflam-matory drugs and possibly immune-suppressants are used in the management of ADS. If care is not taken, ADS can be mis-diagnosed as conjunctivitis because the redness is similar in both conditions. Such mis-diagnosis can be sight-threatening and therefore it is essential that primary eye care practitioners are cautious in all diagnoses of red eye conditions. (S Afr Optom 2012 71(1 51-54

  10. Cataract Surgery in Anterior Megalophthalmos: A Review

    Science.gov (United States)

    GALVIS, Virgilio; TELLO, Alejandro; M. RANGEL, Carlos

    2015-01-01

    Anterior megalophthalmos is characterized by megalocornea associated with a very broad anterior chamber and ciliary ring elongation. It is also called X-linked megalocornea. It is accompanied by early development of cataracts, zonular anomalies, and, rarely, vitreoretinal disorders. Subluxation of a cataract can occur in cataract surgery because of zonular weakness. In addition, in most patients, standard intraocular lens (IOL) decentration is a risk because of the enlarged sulcus and capsular bag. These unique circumstances make cataract surgery challenging. To date, several approaches have been developed. Implantation of a retropupillary iris-claw aphakic intraocular lens may be a good option because it is easier than suturing the IOL and can have better and more stable anatomic and visual outcomes, compared to other techniques. PMID:27350950

  11. Intradural anterior transpetrosal approach.

    Science.gov (United States)

    Ichimura, Shinya; Hori, Satoshi; Hecht, Nils; Czabanka, Marcus; Vajkoczy, Peter

    2016-10-01

    The standard anterior transpetrosal approach (ATPA) for petroclival lesions is fundamentally an epidural approach and has been practiced for many decades quite successfully. However, this approach has some disadvantages, such as epidural venous bleeding around foramen ovale. We describe here our experience with a modified technique for anterior petrosectomy via an intradural approach that overcomes these disadvantages. Five patients with petroclival lesions underwent surgery via the intradural ATPA. The intraoperative hallmarks are detailed, and surgical results are reported. Total removal of the lesions was achieved in two patients with petroclival meningioma and two patients with pontine cavernoma, whereas subtotal removal was achieved in one patient with petroclival meningioma without significant morbidity. No patient experienced cerebrospinal fluid leakage. The intradural approach is allowed to tailor the extent of anterior petrosectomy to the individually required exposure, and the surgical procedure appeared to be more straightforward than via the epidural route. Caveats encountered with the approach were the temporal basal veins that could be spared as well as identification of the petrous apex due to the lack of familial epidural landmarks. The risk of injury to the temporal bridging veins is higher in this approach than in the epidural approach. Intradural approach is recommended in patients with a large epidural venous route, such as sphenobasal and sphenopetrosal vein. Navigation via bone-window computed tomography is useful to identify the petrous apex.

  12. Influence of visual angle on pattern reversal visual evoked potentials

    Directory of Open Access Journals (Sweden)

    Ruchi Kothari

    2014-01-01

    is the appropriate (and optimal check size that can be used for accurate interpretation of PRVEPs. This will help in better assessment of the optic nerve function and integrity of anterior visual pathways.

  13. Anterior knee pain

    Energy Technology Data Exchange (ETDEWEB)

    LLopis, Eva [Hospital de la Ribera, Alzira, Valencia (Spain) and Carretera de Corbera km 1, 46600 Alzira Valencia (Spain)]. E-mail: ellopis@hospital-ribera.com; Padron, Mario [Clinica Cemtro, Ventisquero de la Condesa no. 42, 28035 Madrid (Spain)]. E-mail: mario.padron@clinicacemtro.com

    2007-04-15

    Anterior knee pain is a common complain in all ages athletes. It may be caused by a large variety of injuries. There is a continuum of diagnoses and most of the disorders are closely related. Repeated minor trauma and overuse play an important role for the development of lesions in Hoffa's pad, extensor mechanism, lateral and medial restrain structures or cartilage surface, however usually an increase or change of activity is referred. Although the direct relation of cartilage lesions, especially chondral, and pain is a subject of debate these lesions may be responsible of early osteoarthrosis and can determine athlete's prognosis. The anatomy and biomechanics of patellofemoral joint is complex and symptoms are often unspecific. Transient patellar dislocation has MR distinct features that provide evidence of prior dislocation and rules our complication. However, anterior knee pain more often is related to overuse and repeated minor trauma. Patella and quadriceps tendon have been also implicated in anterior knee pain, as well as lateral or medial restraint structures and Hoffa's pad. US and MR are excellent tools for the diagnosis of superficial tendons, the advantage of MR is that permits to rule out other sources of intraarticular derangements. Due to the complex anatomy and biomechanic of patellofemoral joint maltracking is not fully understood; plain films and CT allow the study of malalignment, new CT and MR kinematic studies have promising results but further studies are needed. Our purpose here is to describe how imaging techniques can be helpful in precisely defining the origin of the patient's complaint and thus improve understanding and management of these injuries.

  14. Elevator Muscle Anterior Resection: A New Technique for Blepharoptosis.

    Science.gov (United States)

    Zigiotti, Gian Luigi; Delia, Gabriele; Grenga, Pierluigi; Pichi, Francesco; Rechichi, Miguel; Jaroudi, Mahmoud O; d'Alcontres, Francesco Stagno; Lupo, Flavia; Meduri, Alessandro

    2016-01-01

    Blepharoptosis is a condition of inadequate upper eyelid position, with a downward displacement of the upper eyelid margin resulting in obstruction of the superior visual field. Levator resection is an effective technique that is routinely used to correct aponeurotic ptosis. The anterior levator resection is the procedure of choice in moderate blepharoptosis when there is moderate to good levator muscle function, furthermore, with an anterior approach, a greater resection can be achieved than by a conjunctival approach. The authors describe a modification in the Putterman technique with a resection done over a plicated elevator, plication that was suggested by Mustardè. The technique has been named as elevator muscle anterior resection. The elevator muscle anterior resection inspires from the Fasanella-Servat operation by the use of a clamp, making the operation simple and predictable.

  15. The anterior cingulate cortex

    Directory of Open Access Journals (Sweden)

    Pavlović D.M.

    2009-01-01

    Full Text Available The anterior cingulate cortex (ACC has a role in attention, analysis of sensory information, error recognition, problem solving, detection of novelty, behavior, emotions, social relations, cognitive control, and regulation of visceral functions. This area is active whenever the individual feels some emotions, solves a problem, or analyzes the pros and cons of an action (if it is a right decision. Analogous areas are also found in higher mammals, especially whales, and they contain spindle neurons that enable complex social interactions. Disturbance of ACC activity is found in dementias, schizophrenia, depression, the obsessive-compulsive syndrome, and other neuropsychiatric diseases.

  16. A new visual stimulation program for improving visual acuity in children with visual impairment: a pilot study

    Directory of Open Access Journals (Sweden)

    Li-Ting eTsai

    2016-04-01

    Full Text Available The purpose of this study was to investigate the effectiveness of visual rehabilitation of a computer-based visual stimulation (VS program combining checkerboard pattern reversal (passive stimulation with oddball stimuli (attentional modulation for improving the visual acuity (VA of visually impaired (VI children and children with amblyopia and additional developmental problems. Six children (3 females, 3 males; mean age = 3.9 ± 2.3 years with impaired VA caused by deficits along the anterior and/or posterior visual pathways were recruited. Participants received eight rounds of VS training (two rounds per week of at least 8 sessions per round. Each session consisted of stimulation with 200 or 300 pattern reversals. Assessments of VA (assessed with the Lea symbol VA test or Teller VA cards, visual evoked potential (VEP, and functional vision (assessed with the Chinese-version Functional Vision Questionnaire, FVQ were carried out before and after the VS program. Significant gains in VA were found after the VS training (VA=1.05 logMAR ± 0.80 to 0.61 logMAR ± 0.53, Z=-2.20, asymptotic significance (2-tailed =0.028. No significant changes were observed in the FVQ assessment (92.8 ± 12.6 to 100.8 ± SD=15.4, Z=-1.46, asymptotic significance (2-tailed = 0.144. VEP measurement showed improvement in P100 latency and amplitude or integration of the waveform in two participants. Our results indicate that a computer-based VS program with passive checkerboard stimulation, oddball stimulus design, and interesting auditory feedback could be considered as a potential intervention option to improve the VA of a wide age range of VI children and children with impaired VA combined with other neurological disorders.

  17. Multidisciplinary management of anterior diastemata

    DEFF Research Database (Denmark)

    Furuse, Adilson Yoshio; Herkrath, Fernando José; Franco, Eduardo Jacomino

    2007-01-01

    Anterior diastemata may compromise the harmony of a patient's smile. Consideration of etiologic factors, previous gingival conditioning, and individual treatment planning are essential in the proper management of anterior diastemata. An integrated orthodontic-restorative approach may enhance...... the aesthetic results when orthodontic therapy itself is not feasible. This article presents integrated orthodonticrestorative solutions of anterior diastemata, associated with the conditioning of the gingival tissue with composite resin, and discusses the most relevant aspects related to their etiology...

  18. THERAPY OF FIBRINOUS PLASTIC ANTERIOR UVEITIS

    Directory of Open Access Journals (Sweden)

    A. L. Onishchenko

    2015-01-01

    Full Text Available Aim. To analyze the efficacy of modified pupillary massage technique using cycloplegic agent Appamide Plus in the treatment of anterior uveitis. Patients and methods. 45 patients (25 men and 20 women aged 21‑69 with endogenous uveitis (51 eyes were enrolled in the study. Etiology of uveitis was identified in 57.7 % of cases: herpes simplex virus (22.2 %; systemic disorders — rheumatoid arthritis, Reiter syndrome, Bechterew’s disease, psoriasis (17.7 %; local infection — purulent periodontitis or sinusitis (11 %. Patients were divided into two groups. Group I received basic therapy in combination with traditional pupillary massage. Group II received basic therapy in combination with modified pupillary massage using Appamide Plus (muscarinic receptor antagonist and alpha adrenergic agonist and plasma exchange with cell mass ozonation. Results. Inflammation of the uveal tract was prevented in all patients. In group I (traditional pupil massage, posterior synechiae persisted in 26 % of cases. In group II (pupil massage using Appamide Plus, anterior chamber humor was transparent, posterior synechiae were broken, normal pupillary response was re-established. Additionally, inflammatory exudate in the anterior chamber and endothelial precipitates resolved by 3.3 days earlier than in group I (р < 0.05. Visual outcomes were also better in Appamide Plus group. T cell-mediated immunity study revealed initial CD3+ cell and T cell subpopulation deficiency. Relative and absolute references of T cells and their subpopulations tended to decrease even when uveitis signs reduced. Conclusions. T cell-mediated immunity depression is probably due to pharmacotherapy. Appamide Plus eye drops are highly effective for therapeutic mydriasis and pupillary massage in the course of anterior uveitis treatment to prevent synechiae formation in enlarged or small pupil.

  19. RETAINED STONE PIECE IN ANTERIOR CHAMBER

    Directory of Open Access Journals (Sweden)

    ZvornicaninJasmin, Nadarevic-VodencarevicAmra

    2015-04-01

    Full Text Available ABSTRACT We read with interest the article by Surekha et al. regarding the retained stone piece in anterior chamber. Similar to the results of previous studies, the authors found that delayed intraocular foreign body (IOFB management can result in good visual outcome without an apparent increased risk of endophthalmitis or other deleterious side effects. However, the authors failed to explain the exact reason for the diminution of vision in patients left eye. It is unclear what the uncorrected visual acuity was and what kind of correction was used, more precisely type and amount of cylinder, given the presence of the corneal opacity. Since the size of the IOFB is approximately 4x4x1mm, significant irido-corneal angle changes resulting in intraocular pressure raise and optic nerve head damage can be expected. Traumatic glaucoma following open globe injury can occur in 2.7 to 19% of cases, with several risk factors associated with glaucoma development (advanced age, poor visual acuity at presentation,perforating rather than penetrating ocular injury,lens injury, presence of vitreous hemorrhage and presence of an IOFB. Earlier reportsof latetraumaticoptic neuropathy onset, even after several years, indicate that this possibility cannot be completely ruled out too. Therefore, repeated intraocular pressure measurements, gonioscopy, pupillary reaction assessment, together with through posterior segment examination including visual field and optical coherence tomography examinations can be useful in determining the possible optic nerve damage as one of the possible reasons for visual acuity reduction. The authors did not suggest any operative treatment at this time. However, it should bear in mind that the inert anterior chamber IOFB could be a risk factor for non-infectious endophthalmitis development even after many years. Also, long term retained anterior chamber foreign body leads to permanent endothelial cell loss and can even result in a corneal

  20. Beyond the core face-processing network: Intracerebral stimulation of a face-selective area in the right anterior fusiform gyrus elicits transient prosopagnosia.

    Science.gov (United States)

    Jonas, Jacques; Rossion, Bruno; Brissart, Hélène; Frismand, Solène; Jacques, Corentin; Hossu, Gabriela; Colnat-Coulbois, Sophie; Vespignani, Hervé; Vignal, Jean-Pierre; Maillard, Louis

    2015-11-01

    According to neuropsychological evidence, a distributed network of regions of the ventral visual pathway - from the lateral occipital cortex to the temporal pole - supports face recognition. However, functional magnetic resonance imaging (fMRI) studies have generally confined ventral face-selective areas to the posterior section of the occipito-temporal cortex, i.e., the inferior occipital gyrus occipital face area (OFA) and the posterior and middle fusiform gyrus fusiform face area (FFA). There is recent evidence that intracranial electrical stimulation of these areas in the right hemisphere elicits face matching and recognition impairments (i.e., prosopagnosia) as well as perceptual face distortions. Here we report a case of transient inability to recognize faces following electrical stimulation of the right anterior fusiform gyrus, in a region located anteriorly to the FFA. There was no perceptual face distortion reported during stimulation. Although no fMRI face-selective responses were found in this region due to a severe signal drop-out as in previous studies, intracerebral face-selective event-related potentials and gamma range electrophysiological responses were found at the critical site of stimulation. These results point to a causal role in face recognition of the right anterior fusiform gyrus and more generally of face-selective areas located beyond the "core" face-processing network in the right ventral temporal cortex. It also illustrates the diagnostic value of intracerebral electrophysiological recordings and stimulation in understanding the neural basis of face recognition and visual recognition in general.

  1. [Anterior cervical hypertrichosis: case report].

    Science.gov (United States)

    Orozco-Gutiérrez, Mario H; Sánchez-Corona, José; García-Ortiz, José E; Castañeda-Cisneros, Gema; Dávalos-Rodríguez, Nory O; Corona-Rivera, Jorge R; García-Cruz, Diana

    2016-10-01

    The non-syndromic anterior cervical hypertrichosis (OMIM N° 600457) is a genetic disorder characterized by a patch of hair at the level of the laryngeal prominence. We present a 12-year-old boy with anterior cervical hypertrichosis and mild generalized hypertrichosis. He has no neurological, ophthalmological or skeletal anomalies. The clinical follow up is 10 years.

  2. Silicone Oil Tamponade Combined with Lensectomy Preserving Anterior Lens Capsule

    Institute of Scientific and Technical Information of China (English)

    LuL; YangJ

    1999-01-01

    Purpose:To investigate the therapeutic effect and indicatio n of silicone oil tamponade combined with lensectomy preserving anterior lens capsule.Methods:Silicone oil tamponade combined with lensectomy preserving anterior lens capsule was performed in 33 cases (33 eyes)of high myopia ,proliferative vitroretinopathy(PVR)D grade and giant retinal tear(GRT).10 cases were onlyeye and 11 cases had harder nucleus of lens.The surgical methods included:1.smashing lens nucleus and lensectomy preserving complete anterior capsule;2,vitrectomy and membrane peeling;3,usage of liquid perfluorocarbin or retinotomy or drainage;4.silicone oil tamponade;5.postoperative Nd;YAG laser for anterior capsulectomy. Results:Follow-up time was 6 months or more in 29 cases.Total retinal reattachment was achieved in 22 cases,macular retinal reattachment in 5 cases.The visual acuity was 20/800 to 20/200 in 13 cases,20/100 to 20/50 in 12 cases.Visual acuity was significantly improved in GRT group(P<0.05).Complications included unexpected anterior capsule break intraoperatively,anterior capsule opacity,silicone oil emulsification and liquid perfluorocarbin remainig postoperatively.Conclusions:Silicone oil tamponade combined with lensectomy preserving anterior capsule was safe and can reduce the operative complications.The indications included:1.GRT complicated with high myopia;2,advanced PVR cases complicated with high myopia in which silicone oil must be used;3.severe lens opacity cases in which silicone oil must be used;4.complex retinal detachment of only ye.

  3. Anterior internal lenticonus accompanied by congenital nuclear cataract

    Institute of Scientific and Technical Information of China (English)

    LIU Zhe; SUN Chuan-bin; YAO Ke

    2011-01-01

    Internal lenticonus is a very rare morphologic abnormality of crystalline lens which has been reported in only several cases in the literature.We herein reported the clinical characteristics and surgical findings of the anterior internal lenticonus accompanied by congenital nuclear cataract.Cataract extraction accompanied with intraocular lens implantation was uneventfully performed,and a good visual outcome was achieved in this case.Viral infection during embryonal and fetal period might account for the formation of the anterior internal lenticonus and congenital nuclear cataract in our case.

  4. Inestabilidad Anterior de Hombro

    Directory of Open Access Journals (Sweden)

    Pablo David Flint Kuran

    2013-11-01

    Full Text Available In­tro­duc­ción La luxación recidivante de hombro es una patología frecuente en pacientes jóvenes, laboralmente activos. Existen numerosas técnicas quirúrgicas para la inestabilidad glenohumeral. La técnica de Bristow, discutida por no ser anatómica y por sus complicaciones, continúa vigente debido al bajo índice de reluxaciones. Los objetivos fueron determinar el índice de recidiva, alteraciones funcionales e índice de consolidación del injerto. Materiales­ y­ Métodos Se evaluaron 24 pacientes del sexo masculino, de entre 19 y 40 años, operados por luxación anterior recidivante de hombro según la técnica de Bristow, entre enero de 2003 y agosto de 2011. Se evaluó la tasa de reluxación, la función articular según el puntaje de Constant y el posicionamiento del injerto con respecto a la superficie articular con tomografía y radiografías para evaluar la consolidación del injerto. Se registraron las complicaciones quirúrgicas. Resultados ­Todos los pacientes eran hombres, con rango de edad de 19 a 40 años. La causa fue traumática en 24 pacientes. Dieciséis pacientes presentaron más de 3 episodios de luxación prequirúrgicos. Según la escala de Constant, 21 obtuvieron entre 96 y 100 puntos, y los restantes, entre 90 y 95 puntos. No hubo nuevos episodios de luxaciones. La tomografía mostró la consolidación en todos los casos. Un paciente tuvo una imagen osteolítica alrededor del tornillo, sin compromiso funcional del hombro. Conclusión La técnica de Bristow para tratar la luxación anterior recidivante de hombro provocó un bajo índice de complicaciones, con resultados funcionales entre excelentes y buenos. No hubo episodios de reluxación y se logró la consolidación del injerto óseo en todos los casos.

  5. The cerebellum and visual perceptual learning: evidence from a motion extrapolation task.

    Science.gov (United States)

    Deluca, Cristina; Golzar, Ashkan; Santandrea, Elisa; Lo Gerfo, Emanuele; Eštočinová, Jana; Moretto, Giuseppe; Fiaschi, Antonio; Panzeri, Marta; Mariotti, Caterina; Tinazzi, Michele; Chelazzi, Leonardo

    2014-09-01

    Visual perceptual learning is widely assumed to reflect plastic changes occurring along the cerebro-cortical visual pathways, including at the earliest stages of processing, though increasing evidence indicates that higher-level brain areas are also involved. Here we addressed the possibility that the cerebellum plays an important role in visual perceptual learning. Within the realm of motor control, the cerebellum supports learning of new skills and recalibration of motor commands when movement execution is consistently perturbed (adaptation). Growing evidence indicates that the cerebellum is also involved in cognition and mediates forms of cognitive learning. Therefore, the obvious question arises whether the cerebellum might play a similar role in learning and adaptation within the perceptual domain. We explored a possible deficit in visual perceptual learning (and adaptation) in patients with cerebellar damage using variants of a novel motion extrapolation, psychophysical paradigm. Compared to their age- and gender-matched controls, patients with focal damage to the posterior (but not the anterior) cerebellum showed strongly diminished learning, in terms of both rate and amount of improvement over time. Consistent with a double-dissociation pattern, patients with focal damage to the anterior cerebellum instead showed more severe clinical motor deficits, indicative of a distinct role of the anterior cerebellum in the motor domain. The collected evidence demonstrates that a pure form of slow-incremental visual perceptual learning is crucially dependent on the intact cerebellum, bearing the notion that the human cerebellum acts as a learning device for motor, cognitive and perceptual functions. We interpret the deficit in terms of an inability to fine-tune predictive models of the incoming flow of visual perceptual input over time. Moreover, our results suggest a strong dissociation between the role of different portions of the cerebellum in motor versus

  6. Experience-dependent spatial expectations in mouse visual cortex

    DEFF Research Database (Denmark)

    Fiser, Aris; Mahringer, David; Oyibo, Hassana K.

    2016-01-01

    primary visual cortex (V1) becomes increasingly informative of spatial location. We found that a subset of V1 neurons exhibited responses that were predictive of the upcoming visual stimulus in a spatially dependent manner and that the omission of an expected stimulus drove strong responses in V1....... Stimulus-predictive responses also emerged in V1-projecting anterior cingulate cortex axons, suggesting that anterior cingulate cortex serves as a source of predictions of visual input to V1. These findings are consistent with the hypothesis that visual cortex forms an internal representation of the visual...... scene based on spatial location and compares this representation with feed-forward visual input....

  7. Electrophysiology in visually impaired children

    NARCIS (Netherlands)

    Genderen, Maria Michielde van

    2006-01-01

    Inherited retinal disorders and posterior visual pathway abnormalities are important causes of visual impairment in children. Visual electrophysiology often is indispensable in diagnosing these conditions. This thesis shows the wide range of use of pediatric electro-ophthalmology, and demonstrates i

  8. Panoramic radiographs underestimate extensions of the anterior loop and mandibular incisive canal

    Energy Technology Data Exchange (ETDEWEB)

    De Brito, Ana Caroline Ramos; Nejaim, Yuri; De Freitas, Deborah Queiroz [Dept. of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, University of Campinas, Sao Paulo (Brazil); De Oliveira Santos, Christiano [Dept. of Stomatology, Public Oral Health and Forensic Dentistry, School of Dentistry of Ribeirao Preto, University of Sao Paulo, Sao Paulo (Brazil)

    2016-09-15

    The purpose of this study was to detect the anterior loop of the mental nerve and the mandibular incisive canal in panoramic radiographs (PAN) and cone-beam computed tomography (CBCT) images, as well as to determine the anterior/mesial extension of these structures in panoramic and cross-sectional reconstructions using PAN and CBCT images. Images (both PAN and CBCT) from 90 patients were evaluated by 2 independent observers. Detection of the anterior loop and the incisive canal were compared between PAN and CBCT. The anterior/mesial extension of these structures was compared between PAN and both cross-sectional and panoramic CBCT reconstructions. In CBCT, the anterior loop and the incisive canal were observed in 7.7% and 24.4% of the hemimandibles, respectively. In PAN, the anterior loop and the incisive canal were detected in 15% and 5.5% of cases, respectively. PAN presented more difficulties in the visualization of structures. The anterior/mesial extensions ranged from 0.0 mm to 19.0 mm on CBCT. PAN underestimated the measurements by approximately 2.0 mm. CBCT appears to be a more reliable imaging modality than PAN for preoperative workups of the anterior mandible. Individual variations in the anterior/mesial extensions of the anterior loop of the mental nerve and the mandibular incisive canal mean that is not prudent to rely on a general safe zone for implant placement or bone surgery in the interforaminal region.

  9. Panoramic radiographs underestimate extensions of the anterior loop and mandibular incisive canal

    Science.gov (United States)

    Nejaim, Yuri; de Freitas, Deborah Queiroz; de Oliveira Santos, Christiano

    2016-01-01

    Purpose The purpose of this study was to detect the anterior loop of the mental nerve and the mandibular incisive canal in panoramic radiographs (PAN) and cone-beam computed tomography (CBCT) images, as well as to determine the anterior/mesial extension of these structures in panoramic and cross-sectional reconstructions using PAN and CBCT images. Materials and Methods Images (both PAN and CBCT) from 90 patients were evaluated by 2 independent observers. Detection of the anterior loop and the incisive canal were compared between PAN and CBCT. The anterior/mesial extension of these structures was compared between PAN and both cross-sectional and panoramic CBCT reconstructions. Results In CBCT, the anterior loop and the incisive canal were observed in 7.7% and 24.4% of the hemimandibles, respectively. In PAN, the anterior loop and the incisive canal were detected in 15% and 5.5% of cases, respectively. PAN presented more difficulties in the visualization of structures. The anterior/mesial extensions ranged from 0.0 mm to 19.0 mm on CBCT. PAN underestimated the measurements by approximately 2.0 mm. Conclusion CBCT appears to be a more reliable imaging modality than PAN for preoperative workups of the anterior mandible. Individual variations in the anterior/mesial extensions of the anterior loop of the mental nerve and the mandibular incisive canal mean that is not prudent to rely on a general safe zone for implant placement or bone surgery in the interforaminal region. PMID:27672611

  10. Component rotation and anterior knee pain after total knee arthroplasty.

    Science.gov (United States)

    Barrack, R L; Schrader, T; Bertot, A J; Wolfe, M W; Myers, L

    2001-11-01

    All patients undergoing cruciate-retaining primary total knee arthroplasty for degenerative osteoarthritis at one center were studied prospectively. Clinical and radiographic followup was obtained at a minimum 5 years in 102 knees in 73 patients. Patients were asked specifically about the presence of the pain in the anterior aspect of the knee in the vicinity of the patella and rated the severity of the pain on a visual analog scale. Significant anterior knee pain rating at least 3 of 10 on the visual analog scale was present in 16 knees (13 patients). Eleven patients with 14 symptomatic knees agreed to undergo computed tomography scanning to accurately determine the rotation of the tibial and femoral components. The epicondylar axis and tibial tubercle were used as references using a previously validated technique. A control group of 11 asymptomatic patients (14 knees), matched for age, gender, and length of followup also underwent computed tomography scanning. All patients in both groups had normal axial alignment. There was a highly significant difference in tibial component rotation between the two groups with the patients with anterior knee pain averaging 6.2 degrees internal rotation compared with 0.4 degrees external rotation in the control group. There also was a significant difference in combined component rotation with the patients with anterior knee pain averaging 4.7 degrees internal rotation compared with 2.6 degrees external rotation in the control group. There was no significant difference in the degree of radiographic patellar tilt or patellar subluxation between the two groups. Patients with combined component internal rotation were more than five times as likely to experience anterior knee pain after total knee arthroplasty compared with those with combined component external rotation. Component malrotation is a significant factor in the development of anterior knee pain after total knee arthroplasty.

  11. Diagnóstico e tratamento do lenticone anterior

    Directory of Open Access Journals (Sweden)

    Ana Luiza Biancardi

    2011-08-01

    Full Text Available Relato de caso de um paciente de 18 anos com sindrome de Alport apresentando perda visual progressiva. A biomicroscopia revelou lenticone anterior bilateral. O paciente realizou tomografia de córnea e segmento anterior com o sistema Scheimpflug (Pentacam e aberrometria e topografia corneana (i-Trace. O paciente foi submetido à facoemulsificação com implante de lente intraocular peça única hidrofóbica (Acrysof® SN60AT. As imagens de Scheimpflug documentaram o lenticone anterior. A aberrometria total mostrou acentuado astigmatismo miópico com acentuada aberração esférica negativa, havendo grande impacto das aberrações de alta ordem (HOA na conversão da letra E de Snellen. O mapa de integração da aberrometria do olho todo com a topografia corneana mostrou maior semelhança das aberrrações totais com as aberrações intraoculares do que com as aberrações da superfície anterior da córnea. Após a cirurgia, o paciente apresentou acuidade visual corrigida igual a 20/20 em ambos os olhos, as imagens de Scheimpflug revelaram lentes intraoculares tópicas e os mapas diferenciais revelaram resolução da miopia e redução das aberrações da alta ordem (total e interna. Os exames de imagem foram úteis para demonstrar o impacto do lenticone anterior na qualidade visual e a resolução das aberrações ópticas após a cirurgia.

  12. Anterior chamber depth during hemodialysis

    Directory of Open Access Journals (Sweden)

    Gracitelli CPB

    2013-08-01

    Full Text Available Carolina Pelegrini Barbosa Gracitelli,1 Francisco Rosa Stefanini,1 Fernando Penha,1 Miguel Ângelo Góes,2 Sérgio Antonio Draibe,2 Maria Eugênia Canziani,2 Augusto Paranhos Junior1 1Ophthalmology Department, 2Division of Nephrology, Federal University of São Paulo – UNIFESP, São Paulo, Brazil Background: Exacerbation of chronic glaucoma or acute glaucoma is occasionally observed in patients undergoing hemodialysis (HD because of anterior chamber depth changes during this therapy. Purpose: To evaluate anterior chamber depth and axial length in patients during HD sessions. Methods: A total of 67 eyes of 35 patients were prospectively enrolled. Axial length and anterior chamber depth were measured using ultrasonic biometry, and these measures were evaluated at three different times during HD sessions. Body weight and blood pressure pre- and post-HD were also measured. Results: There was no difference in the axial length between the three measurements (P = 0.241. We observed a significantly decreased anterior chamber depth (P = 0.002 during HD sessions. Conclusion: Our results support the idea that there is a change in anterior chamber depth in HD sessions. Keywords: anterior chamber, hemodialysis, axial length, acute angle-closure glaucoma

  13. Diffuse anterior retinoblastoma: current concepts

    Directory of Open Access Journals (Sweden)

    Yang J

    2015-07-01

    Full Text Available Jing Yang,1–3 Yalong Dang,1–3 Yu Zhu,1 Chun Zhang2,3 1Department of Ophthalmology, The First Affiliated Hospital, Zhengzhou University, Zhengzhou City, Henan Province, 2Department of Ophthalmology, Peking University Third Hospital, 3Clinical Stem Cell Research Center, Peking University Third Hospital, Beijing, People’s Republic of China Abstract: Diffuse anterior retinoblastoma is a rare variant of retinoblastoma seeding in the area of the vitreous base and anterior chamber. Patients with diffuse anterior retinoblastoma are older than those with the classical types, with the mean age being 6.1 years. The original cells of diffuse anterior retinoblastoma are supposed to be cone precursor. Patients most commonly present with pseudouveitis, pseudohypopyon, and increased intraocular pressure. The retina under fundus examination is likely to be normal, and the clinical features mimic the inflammation progress, which can often lead to misdiagnosis. The published diffuse anterior retinoblastoma cases were diagnosed after fine-needle aspiration biopsy running the potential risk of inducing metastasis. The most common treatment for diffuse anterior retinoblastoma is enucleation followed by systematic chemotherapy according to the patient’s presentation and clinical course. This review summarizes the recent advances in etiology (including tumorigenesis and cell origin, pathology, diagnosis, differential diagnosis, and new treatment. The challenges of early diagnosis and prospects are also discussed. Keywords: pathology, microenvironment, treatment, diagnosis 

  14. Simulation research on the influence of flash stimulation under visual pathway on SSVEP%视觉通路下闪光刺激对SSVEP影响的仿真研究

    Institute of Scientific and Technical Information of China (English)

    郭湛超; 覃玉荣; 赵隆

    2016-01-01

    稳态视觉诱发电位(steady-state visual evoked potentials,SSVEP)是一种在频率固定的重复视觉刺激下出现的大脑皮层稳态响应。针对目前不同学者在不同实验条件下测试闪光刺激的参数(占空比、频率)对SSVEP影响结果差异较大而难以归纳其共性规律问题,本文基于集总参数模型法,将光刺激下视觉通路的同一类神经元等效为一个单元,利用单元间的耦合系数建立视觉通路计算模型,并通过该模型仿真研究闪光刺激的占空比和频率对SSVEP影响的初步规律,为刺激参数的选择提供有价值的理论依据。最后通过实验验证了模型的可靠性及结论的有效性。%Steady-state visual evoked potential (SSVEP)is a steady-state response to a fixed frequency of repetitive visual stimulation in the cerebral cortex.With the issue of huge result differences gained by different stimulus pa-rameters setting about SSVEP,such as duty cycle or frequency,a visual pathway computation model based on the lumped parameter theory was proposed.In this model,the same kind of neurons in visual pathway can be equiva-lent to a module.Using coupling coefficients between different modules,the rule for the impact of stimulus frequen-cy and duty cycle on SSVEP are derived,which can provide a valuable basis of stimulus parameter selection.Final-ly,the model’s reliability and conclusion’s validity are verified by experiment.

  15. Spontaneous Scleral Perforation of an Anterior Chamber Intraocular Lens

    Directory of Open Access Journals (Sweden)

    Oriel Spierer

    2016-05-01

    Full Text Available A routine eye examination of a 69-year-old man revealed a scleral perforation of one of the haptics of the anterior chamber intraocular lens (AC IOL which had been implanted many years ago. The patient was asymptomatic with good visual acuity. His history was negative for any trauma, eye rubbing, topical corticosteroid use, or autoimmune disease. The horizontal and vertical white-to-white diameters of the cornea in the right eye were 11.5 and 10.5 mm, respectively. Anterior segment optical coherence tomography showed the anterior chamber length to be 12.28 mm horizontally and 10.63 mm vertically. The patient underwent an IOL exchange, and the length of the explanted AC IOL was measured to be 12 mm. We speculate that the AC IOL, which was vertically aligned, was oversized. This case demonstrates the need for proper sizing and positioning of an AC IOL. In complex cases where AC IOL may be used, measuring the horizontal and vertical lengths of the anterior chamber by anterior segment optical coherence tomography prior to surgery may be useful.

  16. Spontaneous Scleral Perforation of an Anterior Chamber Intraocular Lens

    Science.gov (United States)

    Spierer, Oriel; O'Brien, Terrence P.

    2016-01-01

    A routine eye examination of a 69-year-old man revealed a scleral perforation of one of the haptics of the anterior chamber intraocular lens (AC IOL) which had been implanted many years ago. The patient was asymptomatic with good visual acuity. His history was negative for any trauma, eye rubbing, topical corticosteroid use, or autoimmune disease. The horizontal and vertical white-to-white diameters of the cornea in the right eye were 11.5 and 10.5 mm, respectively. Anterior segment optical coherence tomography showed the anterior chamber length to be 12.28 mm horizontally and 10.63 mm vertically. The patient underwent an IOL exchange, and the length of the explanted AC IOL was measured to be 12 mm. We speculate that the AC IOL, which was vertically aligned, was oversized. This case demonstrates the need for proper sizing and positioning of an AC IOL. In complex cases where AC IOL may be used, measuring the horizontal and vertical lengths of the anterior chamber by anterior segment optical coherence tomography prior to surgery may be useful. PMID:27462251

  17. Spontaneous Scleral Perforation of an Anterior Chamber Intraocular Lens.

    Science.gov (United States)

    Spierer, Oriel; O'Brien, Terrence P

    2016-01-01

    A routine eye examination of a 69-year-old man revealed a scleral perforation of one of the haptics of the anterior chamber intraocular lens (AC IOL) which had been implanted many years ago. The patient was asymptomatic with good visual acuity. His history was negative for any trauma, eye rubbing, topical corticosteroid use, or autoimmune disease. The horizontal and vertical white-to-white diameters of the cornea in the right eye were 11.5 and 10.5 mm, respectively. Anterior segment optical coherence tomography showed the anterior chamber length to be 12.28 mm horizontally and 10.63 mm vertically. The patient underwent an IOL exchange, and the length of the explanted AC IOL was measured to be 12 mm. We speculate that the AC IOL, which was vertically aligned, was oversized. This case demonstrates the need for proper sizing and positioning of an AC IOL. In complex cases where AC IOL may be used, measuring the horizontal and vertical lengths of the anterior chamber by anterior segment optical coherence tomography prior to surgery may be useful.

  18. Features extraction in anterior and posterior cruciate ligaments analysis.

    Science.gov (United States)

    Zarychta, P

    2015-12-01

    The main aim of this research is finding the feature vectors of the anterior and posterior cruciate ligaments (ACL and PCL). These feature vectors have to clearly define the ligaments structure and make it easier to diagnose them. Extraction of feature vectors is obtained by analysis of both anterior and posterior cruciate ligaments. This procedure is performed after the extraction process of both ligaments. In the first stage in order to reduce the area of analysis a region of interest including cruciate ligaments (CL) is outlined in order to reduce the area of analysis. In this case, the fuzzy C-means algorithm with median modification helping to reduce blurred edges has been implemented. After finding the region of interest (ROI), the fuzzy connectedness procedure is performed. This procedure permits to extract the anterior and posterior cruciate ligament structures. In the last stage, on the basis of the extracted anterior and posterior cruciate ligament structures, 3-dimensional models of the anterior and posterior cruciate ligament are built and the feature vectors created. This methodology has been implemented in MATLAB and tested on clinical T1-weighted magnetic resonance imaging (MRI) slices of the knee joint. The 3D display is based on the Visualization Toolkit (VTK).

  19. Visual Impairment

    Science.gov (United States)

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Visual Impairment KidsHealth > For Teens > Visual Impairment Print A ... with the brain, making vision impossible. What Is Visual Impairment? Many people have some type of visual ...

  20. Visual field

    Science.gov (United States)

    Perimetry; Tangent screen exam; Automated perimetry exam; Goldmann visual field exam; Humphrey visual field exam ... Confrontation visual field exam : This is a quick and basic check of the visual field. The health care provider ...

  1. The use of EMG biofeedback for learning of selective activation of intra-muscular parts within the serratus anterior muscle

    DEFF Research Database (Denmark)

    Holtermann, A; Mork, P J; Andersen, L L;

    2010-01-01

    anterior can be learned with electromyographical (EMG) biofeedback, and whether the lower serratus anterior and the lower trapezius muscle comprise the lower scapula rotation force couple by synergistic activation. Nine healthy males practiced selective activation of intra-muscular parts within...... the serratus anterior with visual EMG biofeedback, while the activity of four parts of the serratus anterior and four parts of the trapezius muscle was recorded. One subject was able to selectively activate both the upper and the lower serratus anterior respectively. Moreover, three subjects managed.......05). The learning of complete selective activation of both the lower and the upper serratus anterior of one subject, and selective activation of either the upper or lower serratus anterior by five subjects designates the promising clinical application of EMG biofeedback for restoring scapular muscle balance...

  2. Clinical Analysis of the Change of Perimetry of 35 Cases with Visual Pathway Diseases%35例视路病变的视野改变与临床分析

    Institute of Scientific and Technical Information of China (English)

    吴仲新; 张文; 张金海; 朱国平; 朱萍; 王健利

    2012-01-01

    Objective To discuss the ophthalmological performance of visual pathway diseases, and enhance the early awareness of visual pathway diseases from the perspective of ophthalmology. Methods We analyzed the diseases sites, clinical manifestation and the results of perimetry of 35 cases with visual pathway diseases which had been definitely diagnosed by CT or MRI with their first outpatient services at Ophthalmology. Results There were 1 patient (2, 86%) experiencing pathological change at the area in front of chiasma, 8 patients (22. 86%) at optic chiasma, 8 patients (22. 86%) at the area behind chiasma and in front of occipital lobe, 18 patients (51.43%) at occipital lobe area. Thirty-four patients (97, 14%) said their major symptom were blurred vision and 6 patients (17. 14%) claimed themselves experiencing hemianopia. Thirty-four patients'(97. 14%) symptom were hemianopia. Among the 8 patients who had optic chiasma, there were 4 patients with 6 eyes had optic atrophy. Conclusion For those patients who said their major symptom was blurred vision or those patients experiencing discus opticus atrophy which cannot be explained by ophthalmological diseases, it should be regular to do the examination of perimetry and further CT/MRI examination should be made when it is necessary.%目的 探讨视路病变的眼科表现,从眼科角度提高对视路病变的早期认识.方法 分析首诊于眼科经CT或MRI确诊的35例视路病变的部位以及临床表现、视野检查结果.结果 视交叉前病变1例(2.86%),视交叉病变8例(22.86%),视交叉后枕叶前病变8例(22.86%),枕叶病变18例(51.43%).主诉视物模糊者34例(97.14%),有偏盲症状者6例(17.14%).视野检查有偏盲者34例(97.14%).8例视交叉疾病中4例6眼有视神经萎缩.结论 有视物模糊主诉或视乳头萎缩而无眼科病变可解释者,应把视野检查作为常规,必要时行CT/MRI检查.

  3. Role of fusiform and anterior temporal cortical areas in facial recognition.

    Science.gov (United States)

    Nasr, Shahin; Tootell, Roger B H

    2012-11-15

    Recent fMRI studies suggest that cortical face processing extends well beyond the fusiform face area (FFA), including unspecified portions of the anterior temporal lobe. However, the exact location of such anterior temporal region(s), and their role during active face recognition, remain unclear. Here we demonstrate that (in addition to FFA) a small bilateral site in the anterior tip of the collateral sulcus ('AT'; the anterior temporal face patch) is selectively activated during recognition of faces but not houses (a non-face object). In contrast to the psychophysical prediction that inverted and contrast reversed faces are processed like other non-face objects, both FFA and AT (but not other visual areas) were also activated during recognition of inverted and contrast reversed faces. However, response accuracy was better correlated to recognition-driven activity in AT, compared to FFA. These data support a segregated, hierarchical model of face recognition processing, extending to the anterior temporal cortex.

  4. Perception of biological motion in visual agnosia

    OpenAIRE

    Elisabeth eHuberle; Paul eRupek; Markus eLappe; Hans-Otto eKarnath

    2012-01-01

    Over the past twenty-five years, visual processing has been discussed in the context of the dual stream hypothesis consisting of a ventral (‘what') and a dorsal ('where') visual information processing pathway. Patients with brain damage of the ventral pathway typically present with signs of visual agnosia, the inability to identify and discriminate objects by visual exploration, but show normal perception of motion perception. A dissociation between the perception of biological motion and non...

  5. MRI of the anterior optic pathways following enucleation

    Energy Technology Data Exchange (ETDEWEB)

    Hardman, J.; Halpin, S.F.S.; Hourihan, M.D. [Department of Neuroradiology, University Hospital of Wales, Cardiff (United Kingdom); Mars, S.; Lane, C. [Department of Opthalmology, University Hospital of Wales, Cardiff (United Kingdom)

    1997-11-01

    We examined five patients who had enucleation of one eye for inflammatory or neoplastic disease, using MRI at 1.5 Tesla. None had symptoms referable to the enucleated orbit. In addition, age- and-sex matched individuals were imaged as control subjects, and a further 15 subjects, referred for other than orbital disease, were reviewed. Measurements were made retrospectively of the dimensions of the optic chiasm to establish normal values. All five patients showed abnormalities on MRI following enucleation: abnormal signal within the optic nerve remnant on short {tau} inversion recovery (STIR) images, and atrophy of the nerve remnant and the chiasm. These findings were not apparent in the control or normal subjects. Such findings are to be expected following enucleation and should not be interpreted as indicating active pathology. (orig.) With 3 figs., 2 tabs., 6 refs.

  6. Anterior cruciate ligament - updating article.

    Science.gov (United States)

    Luzo, Marcus Vinicius Malheiros; Franciozi, Carlos Eduardo da Silveira; Rezende, Fernando Cury; Gracitelli, Guilherme Conforto; Debieux, Pedro; Cohen, Moisés

    2016-01-01

    This updating article on the anterior cruciate ligament (ACL) has the aim of addressing some of the most interesting current topics in this field. Within this stratified approach, it contains the following sections: ACL remnant; anterolateral ligament and combined intra and extra-articular reconstruction; fixation devices; and ACL femoral tunnel creation techniques.

  7. Anterior cruciate ligament - updating article

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius Malheiros Luzo

    2016-08-01

    Full Text Available ABSTRACT This updating article on the anterior cruciate ligament (ACL has the aim of addressing some of the most interesting current topics in this field. Within this stratified approach, it contains the following sections: ACL remnant; anterolateral ligament and combined intra and extra-articular reconstruction; fixation devices; and ACL femoral tunnel creation techniques.

  8. Adjustable muscle plication: a new surgical technique for strabismic patients with high risk for anterior segment ischemia

    Institute of Scientific and Technical Information of China (English)

    Carlos; Laria; David; P.Pi?ero

    2015-01-01

    <正>INTRODUCTION Anterior ciliary arteries provide 70%of the vascular supply of the anterior segment.A significant interruption of the vascular flow of these arteries increases the risk for anterior ischemia.Although the frequency of this special condition is low after strabismus surgery(1:13 000)[1],its effects may involve substantial visual problems[2].We report the successful outcome of a new surgical approach for strabismus management in a case of high risk for anterior ischemia.Specifically,we show the correction of the horizontal ocular deviation by means of an adjustable muscle

  9. Structural and functional brain changes beyond visual system in patients with advanced glaucoma.

    Science.gov (United States)

    Frezzotti, Paolo; Giorgio, Antonio; Motolese, Ilaria; De Leucio, Alessandro; Iester, Michele; Motolese, Eduardo; Federico, Antonio; De Stefano, Nicola

    2014-01-01

    In order to test the hypothesis that in primary open angle glaucoma (POAG), an important cause of irreversible blindness, a spreading of neurodegeneration occurs through the brain, we performed multimodal MRI and subsequent whole-brain explorative voxelwise analyses in 13 advanced POAG patients and 12 age-matched normal controls (NC). Altered integrity (decreased fractional anisotropy or increased diffusivities) of white matter (WM) tracts was found not only along the visual pathway of POAG but also in nonvisual WM tracts (superior longitudinal fascicle, anterior thalamic radiation, corticospinal tract, middle cerebellar peduncle). POAG patients also showed brain atrophy in both visual cortex and other distant grey matter (GM) regions (frontoparietal cortex, hippocampi and cerebellar cortex), decreased functional connectivity (FC) in visual, working memory and dorsal attention networks and increased FC in visual and executive networks. In POAG, abnormalities in structure and FC within and outside visual system correlated with visual field parameters in the poorer performing eyes, thus emphasizing their clinical relevance. Altogether, this represents evidence that a vision disorder such as POAG can be considered a widespread neurodegenerative condition.

  10. Válvula de uretra anterior Anterior urethral valves

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    Silvio Tucci Jr.

    2003-02-01

    Full Text Available Objetivo: apresentar os aspectos clínicos, diagnósticos e terapêuticos de pacientes portadores de válvula da uretra anterior. Descrição: em dois neonatos, o diagnóstico presuntivo de patologia obstrutiva do trato urinário foi sugerido pela ultra-sonografia realizada no período pré-natal, confirmando-se o diagnóstico de válvula de uretra anterior pela avaliação pós-natal. Os pacientes foram submetidos a tratamento cirúrgico paliativo, com vesicostomia temporária e, posteriormente, definitivo, pela fulguração endoscópica das válvulas. Ambos evoluíram com função renal normal. Comentários: a válvula da uretra anterior é anomalia rara que deve ser considerada em meninos com quadro radiológico pré-natal sugestivo de obstrução infravesical, secundariamente à hipótese mais comum de válvula da uretra posterior. Ressaltamos a utilização da vesicostomia como derivação urinária temporária nestes casos, prevenindo potenciais complicações pela manipulação da uretra do recém-nascido.Objective: to discuss clinical signs, diagnostic tools and therapeutics of anterior urethral valves, an obstructive anomaly of the urinary system in males. Description: signs of urinary tract obstruction were identified on pre-natal ultrasound in two male fetuses and the diagnosis of anterior urethral valves was made through post-natal evaluation. As an initial treatment, vesicostomy was performed in both patients. Later, the valves were fulgurated using an endoscopic procedure. During the follow-up period both patients presented normal renal function. Comments: anterior urethral valves are a rare form of urethral anomaly that must be ruled out in boys with pre-natal ultrasound indicating infravesical obstruction. Vesicostomy used as an initial treatment rather than transurethral fulguration may prevent potential complications that can occur due to the small size of the neonatal urethra.

  11. Optic radiation damage in multiple sclerosis is associated with visual dysfunction and retinal thinning - an ultrahigh-field MR pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Sinnecker, Tim [Charite - Universitaetsmedizin Berlin, NeuroCure Clinical Research Center, Berlin (Germany); Asklepios Fachklinikum Teupitz, Department of Neurology, Teupitz (Germany); Oberwahrenbrock, Timm; Zimmermann, Hanna; Ramien, Caren; Brandt, Alexander U. [Charite - Universitaetsmedizin Berlin, NeuroCure Clinical Research Center, Berlin (Germany); Metz, Imke; Brueck, Wolfgang [University Medicine Goettingen, Institute of Neuropathology, Goettingen (Germany); Pfueller, Caspar F.; Doerr, Jan [Charite - Universitaetsmedizin Berlin, NeuroCure Clinical Research Center, Berlin (Germany); Charite - Universitaetsmedizin Berlin, Clinical and Experimental Multiple Sclerosis Research Center, Berlin (Germany); Harms, Lutz; Ruprecht, Klemens [Charite - Universitaetsmedizin Berlin, Clinical and Experimental Multiple Sclerosis Research Center, Berlin (Germany); Charite - Universitaetsmedizin Berlin, Department of Neurology, Berlin (Germany); Hahn, Katrin [Charite - Universitaetsmedizin Berlin, Department of Neurology, Berlin (Germany); Niendorf, Thoralf [Max Delbrueck Center for Molecular Medicine, Berlin Ultrahigh Field Facility (B.U.F.F), Berlin (Germany); Charite - Universitaetsmedizin Berlin and Max Delbrueck Center for Molecular Medicine, Experimental and Clinical Research Center, Berlin (Germany); Paul, Friedemann [Charite - Universitaetsmedizin Berlin, NeuroCure Clinical Research Center, Berlin (Germany); Charite - Universitaetsmedizin Berlin, Clinical and Experimental Multiple Sclerosis Research Center, Berlin (Germany); Charite - Universitaetsmedizin Berlin, Department of Neurology, Berlin (Germany); Charite - Universitaetsmedizin Berlin and Max Delbrueck Center for Molecular Medicine, Experimental and Clinical Research Center, Berlin (Germany); Wuerfel, Jens [Charite - Universitaetsmedizin Berlin, NeuroCure Clinical Research Center, Berlin (Germany); Max Delbrueck Center for Molecular Medicine, Berlin Ultrahigh Field Facility (B.U.F.F), Berlin (Germany); University Medicine Goettingen, Institute of Neuroradiology, Goettingen (Germany)

    2015-01-15

    To investigate posterior visual pathway damage in multiple sclerosis using ultrahigh-field magnetic resonance imaging (MRI) at 7 Tesla (7 T), and to determine its correlation with visual disability and retinal fibre layer (RNFL) damage detectable by optic coherence tomography (OCT). We studied 7 T MRI, OCT, functional acuity contrast testing (FACT), and visually evoked potentials (VEP, n = 16) in 30 patients (including 26 relapsing-remitting MS and four clinically isolated syndrome patients) and 12 healthy controls to quantify RNFL thickness, optic radiation lesion volume, and optic radiation thickness. Optic radiation lesion volume was associated with thinning of the optic radiation (p < 0.001), delayed VEP (p = 0.031), and visual disability indicated by FACT (p = 0.020). Furthermore, we observed an inverse correlation between optic radiation lesion volume and RNFL thickness (p < 0.001), including patients without previous optic neuritis (p < 0.001). Anterior visual pathway damage, but also (subclinical) optic radiation integrity loss detectable by 7 T MRI are common findings in MS that are mutually affected. Given the association between optic radiation damage, visual impairment, and increased VEP latency in this exploratory study of a limited sample size, clinicians should be aware of acute lesions within the optic radiation in patients with (bilateral) visual disturbances. (orig.)

  12. Screening of key genes and inflammatory signalling pathway involved in the pathogenesis of HLA-B27-associated acute anterior uveitis by gene expression microarray%人类白细胞抗原-B27相关性前葡萄膜炎患者差异基因的表达特征

    Institute of Scientific and Technical Information of China (English)

    胡小凤; 卢弘; 王婧; 张孝生; 张晓龙; 刘旭辉; 许卓再; 胡俊敏; 卢清君

    2013-01-01

    Objective To investigate the genes and signalling pathways located upstream of the inflammatory processes in human leukocyte antigen (HLA)-B27-associated acute anterior uveitis by gene expression microarray.Methods Experimental study.HLA-B27-positive and-negative monocytes isolated from human peripheral blood were stimulated with Vibrio cholera lipopolysaccharide (LPS).Gene expression microarrays were used to identify the differentially expressed genes.Differentially expressed (DE) genes were testified by real-time PCR and analyzed by a series of bioinformatics-based techniques such as Gene Ontology,Kyoto Encyclopedia of Genes and Genomes.Results Gene expression microarray analysis revealed marked differences between HLA-B27-positive acute anterior uveitis(AAU) and HLA-B27-negative healthy control peripheral monocytes in the genes that were upregulated in response to LPS stimulation with 1105 genes and 25 genes respectively.Gene Ontology enrichment and pathway analysis indicated that genes participating in protein transport and folding were essential to the inflammatory process.The LPS receptorToll-like receptor(TLR)4 induced TLR signalling pathway and pathway related to Vibrio cholerae infection were located upstream of the network and contribute to the overall response.Among the DE genes,PIK3 CA,PIK3CB,AKT3,and MAPK1 might play critical roles in inflammation.Conclusions Equivalent LPS stimulation induces a different response in HLA-B27-positive peripheral monocytes compared to normal control,suggesting that the TLR pathway is involved in the pathogenesis of HLA-B27-associated AAU.%目的 研究人类白细胞抗原(HLA)-B27相关性前葡萄膜炎患者外周血单核细胞炎症通路差异基因的表达特征.方法 实验研究.抽取3例HLA-B27阳性前葡萄膜炎患者及2例健康对照者外周血,分离后获得的单核细胞经含霍乱弧菌的脂多糖刺激后提取RNA,使用基因表达谱芯片进行检测,实时荧光定

  13. Endoscopic anterior decompression in cervical disc disease

    Directory of Open Access Journals (Sweden)

    Yad Ram Yadav

    2014-01-01

    Full Text Available Background: Although microscopic anterior cervical discectomy with or without fusion are common surgical procedures for treatment of cervical herniated discs, loss of disc height, pseudarthrosis, and adjacent disc degeneration are some of the problems associated with it. This study is aimed to evaluate results of endoscopic microforaminotomy in cervical disc diseases. Materials and Methods: A prospective study of 50 patients of mono segmental soft or hard disc causing myeloradiculopathy was undertaken. A visual analogue scale (VAS for neck and arm pain and functional outcomes using the Nurick grading system were assessed. There were 28, 12, 8, and 2 patients at C5-6, C6-7, C4-5, and C3-4 levels disc diseases, respectively. Patients with two or more level disc, instabilities, disc extending more than half vertebral body height, and previous operation at the same segment were excluded. Results: Age ranged from 21 to 67 years. Average postoperative reduction in disc height, operating time, and blood loss was 1.1 mm, 110 minutes, and 30 ml, respectively. Average pre-operative VAS score for arm pain and Nurick grading was 7.6 and 2.7, which improved to 1.9 and 0.82, respectively. All patients improved; 1, 2, 3 grade improvement was seen in 10, 27, and 10 patients, respectively. There was no significant complication or any mortality. Conclusion: Although longer follow up of large number of patients is required, endoscopic microforaminotomy is a safe and an effective alternative to microscopic anterior discectomy with or without fusion.

  14. Clinical Outcomes Following Revision Anterior Shoulder Stabilization

    Science.gov (United States)

    Frank, Rachel M.; Mellano, Chris; Shin, Jason J.; Feldheim, Terrence F.; Mascarenhas, Randhir; Yanke, Adam Blair; Cole, Brian J.; Nicholson, Gregory P.; Romeo, Anthony A.; Verma, Nikhil N.

    2015-01-01

    Objectives: The purpose of this study was to determine the clinical outcomes following revision anterior shoulder stabilization performed either via all-arthroscopic soft tissue repair or via Latarjet coracoid transfer. Methods: A retrospective review of prospectively collected data on 91 shoulders undergoing revision anterior shoulder stabilization was performed. All patients underwent prior soft tissue stabilization; those with prior open bone grafting procedures were excluded. For patients with 25% glenoid bone loss, Latarjet was performed (n=28). Patients were queried regarding recurrent instability (subluxation or dislocation). Clinical outcomes were evaluated using validated patient reported outcome questionnaires including the American Shoulder and Elbow Surgeons (ASES) score, Simple Shoulder Test (SST), visual analog scale (VAS) for pain, and Western Ontario Shoulder Instability Index (WOSI). Results: A total of 63 shoulders in 62 patients (46 males, 16 females) with an average age of 23.2 ± 6.9 years were included in the revision arthroscopy group. At an average follow-up of 46.9 ± 16.8 months (range, 15 to 78), the mean WOSI score was 80.1 (range, 15.0 to 100), and there were significant improvements (pLatarjet group. Thirteen (46%) had more than one previous stabilization attempt. ), the average WOSI score was 71.9, and there were significant improvements (pLatarjet. Conclusion: Both arthroscopic revision stabilization and Latarjet coracoid transfer result in satisfactory outcomes in patients who have failed previous arthroscopic capsulolabral repair. Recurrent instability rates were higher in the all-arthroscopic group (19% versus 7%). Longer-term studies are required to determine whether similar results are maintained over time, and to provide guidance on focused clinical indications for this challenging patient population.

  15. A case of anterior ischemic optic neuropathy associated with uveitis

    Directory of Open Access Journals (Sweden)

    Sugahara M

    2013-05-01

    Full Text Available Michitaka Sugahara, Takayuki Fujimoto, Kyoko Shidara, Kenji Inoue, Masato Wakakura Inouye Eye Hospital, Tokyo, Japan Introduction: Here, we describe a patient who presented with anterior ischemic optic neuropathy (AION and subsequently developed uveitis. Case: A 69-year-old man was referred to our hospital and initially presented with best-corrected visual acuities (BCVA of 20/40 (right eye and 20/1000 (left eye and relative afferent pupillary defect. Slit-lamp examination revealed no signs of ocular inflammation in either eye. Fundus examination revealed left-eye swelling and a pale superior optic disc, and Goldmann perimetry revealed left-eye inferior hemianopia. The patient was diagnosed with nonarteritic AION in the left eye. One week later, the patient returned to the hospital because of vision loss. The BCVA of the left eye was so poor that the patient could only count fingers. Slit-lamp examination revealed 1+ cells in the anterior chamber and the anterior vitreous in both eyes. Funduscopic examination revealed vasculitis and exudates in both eyes. The patient was diagnosed with bilateral panuveitis, and treatment with topical betamethasone was started. No other physical findings resulting from other autoimmune or infectious diseases were found. No additional treatments were administered, and optic disc edema in the left eye improved, and the retinal exudates disappeared in 3 months. The patient's BCVA improved after cataract surgery was performed. Conclusion: Panuveitis most likely manifests after the development of AION. Keywords: anterior ischemic optic neuropathy, uveitis

  16. Anterior uveitis following eyebrow epilation with alexandrite laser

    Directory of Open Access Journals (Sweden)

    Karabela Y

    2015-09-01

    Full Text Available Yunus Karabela,1 Mustafa Eliaçik2 1Department of Ophthalmology, Esenler Hospital, Istanbul Medipol University, Istanbul, Turkey; 2Department of Ophthalmology, Kadiköy Medipol Hospital, Istanbul Medipol University, Istanbul, Turkey Abstract: Ocular tissues are known to be sensitive to damage from exposure to laser emissions. This study reports the case of a female patient with acute unilateral anterior uveitis caused by alexandrite laser-assisted hair removal of the eyebrows. We report a 38-year-old female who presented with unilateral eye pain, redness, and photophobia after receiving alexandrite (755 nm laser epilation of both eyebrows. Best corrected visual acuity was 20/20 in both eyes. Right eye examination was normal. Left eye examination showed conjunctival injection and 2+/3+ cells in the anterior chamber. Intraocular pressure and fundus examination were normal. Topical steroids and cycloplegic drops were prescribed for 3 weeks. At the end of the 3-week follow-up, best corrected visual acuity was 20/20, and intraocular pressure and fundus examination were normal in both eyes. The left eye was white, and the anterior chamber was clear. The patient continues to be monitored. In conclusion, without adequate protective eyewear, laser hair removal of the eyebrows with alexandrite laser can lead to ocular damage. Keywords: uveitis, laser exposure, photothermolysis, laser hair removal, photoepilation

  17. The anterior insular cortex represents breaches of taste identity expectation.

    Science.gov (United States)

    Veldhuizen, Maria G; Douglas, Danielle; Aschenbrenner, Katja; Gitelman, Darren R; Small, Dana M

    2011-10-12

    Despite the importance of breaches of taste identity expectation for survival, its neural correlate is unknown. We used fMRI in 16 women to examine brain response to expected and unexpected receipt of sweet taste and tasteless/odorless solutions. During expected trials (70%), subjects heard "sweet" or "tasteless" and received the liquid indicated by the cue. During unexpected trials (30%), subjects heard sweet but received tasteless or they heard tasteless but received sweet. After delivery, subjects indicated stimulus identity by pressing a button. Reaction time was faster and more accurate after valid cuing, indicating that the cues altered expectancy as intended. Tasting unexpected versus expected stimuli resulted in greater deactivation in fusiform gyri, possibly reflecting greater suppression of visual object regions when orienting to, and identifying, an unexpected taste. Significantly greater activation to unexpected versus expected stimuli occurred in areas related to taste (thalamus, anterior insula), reward [ventral striatum (VS), orbitofrontal cortex], and attention [anterior cingulate cortex, inferior frontal gyrus, intraparietal sulcus (IPS)]. We also observed an interaction between stimulus and expectation in the anterior insula (primary taste cortex). Here response was greater for unexpected versus expected sweet compared with unexpected versus expected tasteless, indicating that this region is preferentially sensitive to breaches of taste expectation. Connectivity analyses confirmed that expectation enhanced network interactions, with IPS and VS influencing insular responses. We conclude that unexpected oral stimulation results in suppression of visual cortex and upregulation of sensory, attention, and reward regions to support orientation, identification, and learning about salient stimuli.

  18. Anterior hippocampus and goal-directed spatial decision making.

    Science.gov (United States)

    Viard, Armelle; Doeller, Christian F; Hartley, Tom; Bird, Chris M; Burgess, Neil

    2011-03-23

    Planning spatial paths through our environment is an important part of everyday life and is supported by a neural system including the hippocampus and prefrontal cortex. Here we investigated the precise functional roles of the components of this system in humans by using fMRI as participants performed a simple goal-directed route-planning task. Participants had to choose the shorter of two routes to a goal in a visual scene that might contain a barrier blocking the most direct route, requiring a detour, or might be obscured by a curtain, requiring memory for the scene. The participant's start position was varied to parametrically manipulate their proximity to the goal and the difference in length of the two routes. Activity in medial prefrontal cortex, precuneus, and left posterior parietal cortex was associated with detour planning, regardless of difficulty, whereas activity in parahippocampal gyrus was associated with remembering the spatial layout of the visual scene. Activity in bilateral anterior hippocampal formation showed a strong increase the closer the start position was to the goal, together with medial prefrontal, medial and posterior parietal cortices. Our results are consistent with computational models in which goal proximity is used to guide subsequent navigation and with the association of anterior hippocampal areas with nonspatial functions such as arousal and reward expectancy. They illustrate how spatial and nonspatial functions combine within the anterior hippocampus, and how these functions interact with parahippocampal, parietal, and prefrontal areas in decision making and mnemonic function.

  19. Changes in brain function and anatomical structure following treatment of hyperbaric oxygen for visual pathway abnormalities In 16 cases Evaluation of functional magnetic resonance Imaging combined with diffusion tensor imaging

    Institute of Scientific and Technical Information of China (English)

    Ziqian Chen; Ping Ni; Hui Xiao; Jinhua Chen; Gennian Qian; Youqiang Ye; Shangwen Xu; Jinliang Wang; Xizhang Yang

    2008-01-01

    BACKGROUND:There is a growing research focus on the combination of blood oxygenation level dependent functional magnetic resonance imaging(BOLD-fMRI)and diffusion tensor imaging(DTI)to evaluate visual cortical function and structural changes in the cerebrum,as well as morphological changes to the white matter fiber tracks,after visual pathway lesions.However,the combined application of BOLD-fMRI and DTI in treating of visual pathway abnormalities still requires further studies. OBJECTIVE:To observe and evaluate the effects of hyperbaric oxygen on visual pathway abnormalities,and to evaluate the characteristics of cerebral function and anatomic structural changes by using BOLD-fMRI combined with DTI technique. DESIGN:Case contrast observation. SETTING:Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA.PARTICIPANTS:Sixteen patients(9 males and 7 females,15-77 years old)with lateral or bilateral visual disorder induced by visual pathway lesions were selected from the Department of Neurology,Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA from January 2006 to May 2007.These patients comprised the lesion group.Measures of interventional therapy:hyperbaric oxygen of two normal atmospheres for three courses(10 d/course)and routine internal medicine treatment.In addition,12 healthy subjects of similar sex and age to the lesion group were regarded as the control group.The control group underwent routine ophthalmological and ocular fundus examinations; diagnostic results were normal. The experiment received confirmed consent from the local ethic committee,and all patients provided informed consent.METHODS:BOLD-fMRI and DTI manifestations in the lesion group were observed before and after hyperbaric oxygen intervention,and the results were compared with the control group.The subjects were positioned on their back,and BOLD-fMRI images were collected with the following GRE EPI sequence:TR= 2 000 ms,TE=40 ms,layer thickness=5 mm

  20. Technical note: Endoscopic resection of a dermoid cyst anchored to the anterior optic chiasm

    Directory of Open Access Journals (Sweden)

    Yuichiro Yoneoka, MD, PhD

    2014-06-01

    Conclusion: To the best of our knowledge, ours is the only case of a dermoid cyst anchored to the anterior optic chiasma, which was visually confirmed under endoscopic observation. After surgery, the patient presented a transient impairment of the visual field, which was not evident at four month follow-up. It will contribute to a similar case, in which surgeons hesitate to make an incision in the optic chiasm. A subtotal excision should be considered in cases of dermoid cysts anchored to the anterior optic chiasm, because all the previously reported cases of suprasellar dermoid cysts are young people or those who have a relatively long life expectancy.

  1. Distinct acute zones for visual stimuli in different visual tasks in Drosophila.

    Directory of Open Access Journals (Sweden)

    Xing Yang

    Full Text Available The fruit fly Drosophila melanogaster has a sophisticated visual system and exhibits complex visual behaviors. Visual responses, vision processing and higher cognitive processes in Drosophila have been studied extensively. However, little is known about whether the retinal location of visual stimuli can affect fruit fly performance in various visual tasks. We tested the response of wild-type Berlin flies to visual stimuli at several vertical locations. Three paradigms were used in our study: visual operant conditioning, visual object fixation and optomotor response. We observed an acute zone for visual feature memorization in the upper visual field when visual patterns were presented with a black background. However, when a white background was used, the acute zone was in the lower visual field. Similar to visual feature memorization, the best locations for visual object fixation and optomotor response to a single moving stripe were in the lower visual field with a white background and the upper visual field with a black background. The preferred location for the optomotor response to moving gratings was around the equator of the visual field. Our results suggest that different visual processing pathways are involved in different visual tasks and that there is a certain degree of overlap between the pathways for visual feature memorization, visual object fixation and optomotor response.

  2. Functional and structural amygdala - anterior cingulate connectivity correlates with attentional bias to masked fearful faces.

    Science.gov (United States)

    Carlson, Joshua M; Cha, Jiook; Mujica-Parodi, Lilianne R

    2013-10-01

    An attentional bias to threat has been causally related to anxiety. Recent research has linked nonconscious attentional bias to threat with variability in the integrity of the amygdala - anterior cingulate pathway, which sheds light on the neuroanatomical basis for a behavioral precursor to anxiety. However, the extent to which structural variability in amygdala - anterior cingulate integrity relates to the functional connectivity within this pathway and how such functional connectivity may relate to attention bias behavior, remain critical missing pieces of the puzzle. In 15 individuals we measured the structural integrity of the amygdala - prefrontal pathway with diffusion tensor-weighted MRI (magnetic resonance imaging), amygdala-seeded intrinsic functional connectivity to the anterior cingulate, and attentional bias toward backward masked fearful faces with a dot-probe task. We found that greater biases in attention to threat predicted greater levels of uncinate fasciculus integrity, greater positive amygdala - anterior cingulate functional connectivity, and greater amygdala coupling with a broader social perception network including the superior temporal sulcus, tempoparietal junction (TPJ), and somatosensory cortex. Additionally, greater levels of uncinate fasciculus integrity correlated with greater levels of amygdala - anterior cingulate intrinsic functional connectivity. Thus, high bias individuals displayed a heightened degree of amygdala - anterior cingulate connectivity during basal conditions, which we believe predisposes these individuals to focus their attention on signals of threat within their environment.

  3. Application of fMRI to obesity research: differences in reward pathway activation measured with fMRI BOLD during visual presentation of high and low calorie foods

    Science.gov (United States)

    Tsao, Sinchai; Adam, Tanja C.; Goran, Michael I.; Singh, Manbir

    2012-03-01

    The factors behind the neural mechanisms that motivate food choice and obesity are not well known. Furthermore, it is not known when these neural mechanisms develop and how they are influenced by both genetic and environmental factors. This study uses fMRI together with clinical data to shed light on the aforementioned questions by investigating how appetite-related activation in the brain changes with low versus high caloric foods in pre-pubescent girls. Previous studies have shown that obese adults have less striatal D2 receptors and thus reduced Dopamine (DA) signaling leading to the reward-deficit theory of obesity. However, overeating in itself reduces D2 receptor density, D2 sensitivity and thus reward sensitivity. The results of this study will show how early these neural mechanisms develop and what effect the drastic endocrinological changes during puberty has on these mechanisms. Our preliminary results showed increased activations in the Putamen, Insula, Thalamus and Hippocampus when looking at activations where High Calorie > Low Calorie. When comparing High Calorie > Control and Low Calorie > Control, the High > Control test showed increased significant activation in the frontal lobe. The Low > Control also yielded significant activation in the Left and Right Fusiform Gyrus, which did not appear in the High > Control test. These results indicate that the reward pathway activations previously shown in post-puberty and adults are present in pre-pubescent teens. These results may suggest that some of the preferential neural mechanisms of reward are already present pre-puberty.

  4. Fenestration of the anterior cerebral artery

    Energy Technology Data Exchange (ETDEWEB)

    Ito, J.; Washiyama, K.; Hong, K.C.; Ibuchi, Y.

    1981-08-01

    Three cases of angiographically demonstrated fenestration of the anterior cerebral artery are reported. Fenestration occurred at the medial half of the horizontal segment of the anterior cerebral artery in all cases. Its embryology and clinical significance are briefly discussed, and the anatomical and radiological literature on fenestration of the anterior cerebral artery is reviewed.

  5. 38 CFR 3.379 - Anterior poliomyelitis.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Anterior poliomyelitis. 3... Specific Diseases § 3.379 Anterior poliomyelitis. If the first manifestations of acute anterior poliomyelitis present themselves in a veteran within 35 days of termination of active military service, it...

  6. Epidermoid cyst in Anterior, Middle

    Directory of Open Access Journals (Sweden)

    Kankane Vivek Kumar

    2016-09-01

    Full Text Available Epidermoid cysts are benign slow growing more often extra-axial tumors that insinuate between brain structures, we present the clinical, imaging, and pathological findings in 35 years old female patients with atypical epidermoid cysts which was situated anterior, middle & posterior cranial fossa. NCCT head revealed hypodense lesion over right temporal and perisylvian region with extension in prepontine cistern with mass effect & midline shift and MRI findings revealed a non-enhancing heterogeneous signal intensity cystic lesion in right frontal & temporal region extending into prepontine cistern with restricted diffusion. Patient was detoriated in night of same day of admission, emergency Fronto-temporal craniotomy with anterior peterousectomy and subtotal resection was done. The histological examination confirms the epidermoid cyst. The timing of ectodermal tissue sequestration during fetal development may account for the occurrence of atypical epidermoid cysts.

  7. Transcriptional activation via DNA-looping: visualization of intermediates in the activation pathway of E. coli RNA polymerase x sigma 54 holoenzyme by scanning force microscopy.

    Science.gov (United States)

    Rippe, K; Guthold, M; von Hippel, P H; Bustamante, C

    1997-07-11

    Scanning force microscopy (SFM) has been used to study transcriptional activation of Escherichia coli RNA polymerase x sigma 54 (RNAP x sigma 54) at the glnA promoter by the constitutive mutant NtrC(D54E,S160F) of the NtrC Protein (nitrogen regulatory protein C). DNA-protein complexes were deposited on mica and images were recorded in air. The DNA template was a 726 bp linear fragment with two NtrC binding sites located at the end and about 460 bp away from the RNAP x sigma 54 glnA promoter. By choosing appropriate conditions the structure of various intermediates in the transcription process could be visualized and analyzed: (1) different multimeric complexes of NtrC(D54E,S160F) dimers bound to the DNA template; (2) the closed complex of RNAP x sigma 54 at the glnA promoter; (3) association between DNA bound RNAP x sigma 54 and NtrC(D54E,S160F) with the intervening DNA looped out; and (4) the activated open promoter complex of RNAP x sigma 54. Measurements of the DNA bending angle of RNAP x sigma 54 closed promoter complexes yielded an apparent bending angle of 49(+/-24) degrees. Under conditions that allowed the formation of the open promoter complex, the distribution of bending angles displayed two peaks at 50(+/-24) degrees and 114(+/-18) degrees, suggesting that the transition from the RNAP x sigma 54 closed complex to the open complex is accompanied by an increase of the DNA bending angle.

  8. The TALE class homeobox gene Smed-prep defines the anterior compartment for head regeneration.

    Directory of Open Access Journals (Sweden)

    Daniel A Felix

    2010-04-01

    Full Text Available Planaria continue to blossom as a model system for understanding all aspects of regeneration. They provide an opportunity to understand how the replacement of missing tissues from preexisting adult tissue is orchestrated at the molecular level. When amputated along any plane, planaria are capable of regenerating all missing tissue and rescaling all structures to the new size of the animal. Recently, rapid progress has been made in understanding the developmental pathways that control planarian regeneration. In particular Wnt/beta-catenin signaling is central in promoting posterior fates and inhibiting anterior identity. Currently the mechanisms that actively promote anterior identity remain unknown. Here, Smed-prep, encoding a TALE class homeodomain, is described as the first gene necessary for correct anterior fate and patterning during planarian regeneration. Smed-prep is expressed at high levels in the anterior portion of whole animals, and Smed-prep(RNAi leads to loss of the whole brain during anterior regeneration, but not during lateral regeneration or homeostasis in intact worms. Expression of markers of different anterior fated cells are greatly reduced or lost in Smed-prep(RNAi animals. We find that the ectopic anterior structures induced by abrogation of Wnt signaling also require Smed-prep to form. We use double knockdown experiments with the S. mediterranea ortholog of nou-darake (that when knocked down induces ectopic brain formation to show that Smed-prep defines an anterior fated compartment within which stem cells are permitted to assume brain fate, but is not required directly for this differentiation process. Smed-prep is the first gene clearly implicated as being necessary for promoting anterior fate and the first homeobox gene implicated in establishing positional identity during regeneration. Together our results suggest that Smed-prep is required in stem cell progeny as they form the anterior regenerative blastema and is

  9. The TALE class homeobox gene Smed-prep defines the anterior compartment for head regeneration.

    Science.gov (United States)

    Felix, Daniel A; Aboobaker, A Aziz

    2010-04-22

    Planaria continue to blossom as a model system for understanding all aspects of regeneration. They provide an opportunity to understand how the replacement of missing tissues from preexisting adult tissue is orchestrated at the molecular level. When amputated along any plane, planaria are capable of regenerating all missing tissue and rescaling all structures to the new size of the animal. Recently, rapid progress has been made in understanding the developmental pathways that control planarian regeneration. In particular Wnt/beta-catenin signaling is central in promoting posterior fates and inhibiting anterior identity. Currently the mechanisms that actively promote anterior identity remain unknown. Here, Smed-prep, encoding a TALE class homeodomain, is described as the first gene necessary for correct anterior fate and patterning during planarian regeneration. Smed-prep is expressed at high levels in the anterior portion of whole animals, and Smed-prep(RNAi) leads to loss of the whole brain during anterior regeneration, but not during lateral regeneration or homeostasis in intact worms. Expression of markers of different anterior fated cells are greatly reduced or lost in Smed-prep(RNAi) animals. We find that the ectopic anterior structures induced by abrogation of Wnt signaling also require Smed-prep to form. We use double knockdown experiments with the S. mediterranea ortholog of nou-darake (that when knocked down induces ectopic brain formation) to show that Smed-prep defines an anterior fated compartment within which stem cells are permitted to assume brain fate, but is not required directly for this differentiation process. Smed-prep is the first gene clearly implicated as being necessary for promoting anterior fate and the first homeobox gene implicated in establishing positional identity during regeneration. Together our results suggest that Smed-prep is required in stem cell progeny as they form the anterior regenerative blastema and is required for

  10. Outcomes of Phacoemulsification with Anterior Chamber Maintainer in Vitrectomized Eyes

    Directory of Open Access Journals (Sweden)

    Elif Betül Türkoğlu

    2012-07-01

    Full Text Available Pur po se: To evaluate the outcomes of phacoemulsification with anterior chamber maintainer in vitrectomized eyes with complicated cataract. Ma te ri al and Met hod: Twenty eyes of 20 patients who developed complicated cataract after pars plana vitrectomy (PPV were included in the study. Phacoemulsification with clear corneal incision and foldable intraocular lens implantation was performed. In group 1, anterior chamber maintainer (ACM was used during phacoemusification and in group 2, ACM was not used. Pre- and postoperative visual acuities as well as per- and postoperative complications were reviewed retrospectively. Re sults: Anterior chamber maintainer was used during the surgery in 12 (60% cases and was not used in 8 (40% cases. Phacoemulsification was performed 16.5±9.2 (4-40 months after PPV. Best-corrected visual acuities were between hand motions and 0.4 preoperatively and between counting fingers from 1 meter and 1.0 postoperatively in group 1. Best-corrected visual acuities were between hand motions and 0.1 preoperatively and between counting fingers from 1 meter and 0.8 postoperatively in group 2. Posterior capsule was ruptured in 1 eye peroperatively in group 1. In group 2, phacoemulsification was more difficult due to deep anterior chamber in 8 eyes and intraoperative complications were iris sphincter rupture in 1 eye and posterior capsule rupture in 1 eye. Mild corneal edema in 7 (58.3% eyes, fibrin reaction in 2 (16.6%, intraocular lens decentralization in 1 (8.3% and posterior capsule opacification in 4 (33.3% eyes were the postoperative complications in group 1. Mild corneal edema in 5 (62.5% eyes, fibrin reaction in 1 (12.5% and posterior capsule opacification in 2 (25% eyes were the postoperative complications in group 2. Dis cus si on: Complicated cataracts which may develop after PPV can be treated safely with phacoemulsification. Continuous irrigation during the surgery may provide a stable anterior chamber and prevents

  11. Assessment of visual disability using visual evoked potentials

    Directory of Open Access Journals (Sweden)

    Jeon Jihoon

    2012-08-01

    Full Text Available Abstract Background The purpose of this study is to validate the use of visual evoked potential (VEP to objectively quantify visual acuity in normal and amblyopic patients, and determine if it is possible to predict visual acuity in disability assessment to register visual pathway lesions. Methods A retrospective chart review was conducted of patients diagnosed with normal vision, unilateral amblyopia, optic neuritis, and visual disability who visited the university medical center for registration from March 2007 to October 2009. The study included 20 normal subjects (20 right eyes: 10 females, 10 males, ages 9–42 years, 18 unilateral amblyopic patients (18 amblyopic eyes, ages 19–36 years, 19 optic neuritis patients (19 eyes: ages 9–71 years, and 10 patients with visual disability having visual pathway lesions. Amplitude and latencies were analyzed and correlations with visual acuity (logMAR were derived from 20 normal and 18 amblyopic subjects. Correlation of VEP amplitude and visual acuity (logMAR of 19 optic neuritis patients confirmed relationships between visual acuity and amplitude. We calculated the objective visual acuity (logMAR of 16 eyes from 10 patients to diagnose the presence or absence of visual disability using relations derived from 20 normal and 18 amblyopic eyes. Results Linear regression analyses between amplitude of pattern visual evoked potentials and visual acuity (logMAR of 38 eyes from normal (right eyes and amblyopic (amblyopic eyes subjects were significant [y = −0.072x + 1.22, x: VEP amplitude, y: visual acuity (logMAR]. There were no significant differences between visual acuity prediction values, which substituted amplitude values of 19 eyes with optic neuritis into function. We calculated the objective visual acuity of 16 eyes of 10 patients to diagnose the presence or absence of visual disability using relations of y = −0.072x + 1.22 (−0.072. This resulted in a prediction

  12. Clinical outcomes of pars plicata anterior vitrectomy: 2-year results

    Directory of Open Access Journals (Sweden)

    Priya Narang

    2015-01-01

    Full Text Available Purpose: To demonstrate the safety and outcome of a surgical approach that uses pars plicata site for anterior vitrectomy during phacoemulsification procedure complicated by posterior capsule rupture and residual cortical matter. Design: Single center, retrospective, interventional, noncomparative study. Materials and Methods: Medical records of a consecutive series of 35 eyes of 35 patients who underwent pars plicata anterior vitrectomy (PPAV were reviewed. The main outcome measures were corrected and uncorrected distance visual acuity (CDVA, UDVA, early and late postoperative complications and intraocular pressure (IOP. Ultrasound biomicroscopic (UBM evaluation of sclerotomy site and spectral domain optical coherence tomography analysis for central macular thickness (CMT was performed. The final visual outcome at 2 years was evaluated. Results: At 2 years follow-up, the mean postoperative UDVA (logarithm of the minimum angle of resolution [logMAR] and CDVA (logMAR was 0.49 ± 0.26 and 0.19 ± 0.14, respectively. There was no significant change in the IOP (P = 0.061 and the mean CMT at 2 years was 192.5 ± 5.54 mm. The postoperative UBM image of the sclerotomy site at 8 weeks demonstrated a clear wound without any vitreous adhesion or incarceration. Intraoperative hyphema was seen in 1 (2.8% case and postoperative uveitis was seen in 2 (5.7% cases, which resolved with medications. No case of an iatrogenic retinal break or retinal detachment was reported. Conclusions: PPAV enables a closed chamber approach, allows thorough cleanup of vitreous in the pupillary plane and anterior chamber and affords better access to the subincisional and retropupillary cortical remnant with a significant visual outcome and an acceptable complication rate.

  13. Alzheimer's disease: A review of its visual system neuropathology. Optical coherence tomography-a potential role as a study tool in vivo.

    Science.gov (United States)

    Cunha, J P; Moura-Coelho, N; Proença, R P; Dias-Santos, A; Ferreira, J; Louro, C; Castanheira-Dinis, A

    2016-11-01

    Alzheimer's disease (AD) is a prevalent, long-term progressive degenerative disorder with great social impact. It is currently thought that, in addition to neurodegeneration, vascular changes also play a role in the pathophysiology of the disease. Visual symptoms are frequent and are an early clinical manifestation; a number of psychophysiologic changes occur in visual function, including visual field defects, abnormal contrast sensitivity, abnormalities in color vision, depth perception deficits, and motion detection abnormalities. These visual changes were initially believed to be solely due to neurodegeneration in the posterior visual pathway. However, evidence from pathology studies in both animal models of AD and humans has demonstrated that neurodegeneration also takes place in the anterior visual pathway, with involvement of the retinal ganglion cells' (RGCs) dendrites, somata, and axons in the optic nerve. These studies additionally showed that patients with AD have changes in retinal and choroidal microvasculature. Pathology findings have been corroborated in in-vivo assessment of the retina and optic nerve head (ONH), as well as the retinal and choroidal vasculature. Optical coherence tomography (OCT) in particular has shown great utility in the assessment of these changes, and it may become a useful tool for early detection and monitoring disease progression in AD. The authors make a review of the current understanding of retinal and choroidal pathological changes in patients with AD, with particular focus on in-vivo evidence of retinal and choroidal neurodegenerative and microvascular changes using OCT technology.

  14. Spectral domain optical coherence tomography study of pearl-like lesions in the anterior chamber

    Directory of Open Access Journals (Sweden)

    Soliman W

    2012-06-01

    Full Text Available Wael Soliman*, Ehab I Wasfi*, Omar M AliDepartment of Ophthalmology, Assiut University Hospital, Assiut University, Assiut, Egypt*These authors contributed equally to this workAim: To study the morphological pattern of pearl-like lesions in the anterior chambers of children before and after management using anterior segment spectral domain optical coherence tomography (SD-OCT.Patients and methods: This was a prospective, observational cross-sectional study of patients presenting with peculiar pearl-like lesions in the anterior chamber of their eyes. 1 mL of betamethasone sodium phosphate (2 mg/mL and betamethasone dipropionate (5 mg/mL was injected subconjunctivally. Follow-ups of all patients were conducted for a period of 6 weeks. Anterior segment imaging was done using SD-OCT and also photo slit lamp before and after management.Results: Twelve eyes of 12 patients were included in this study. These patients presented with pearl-like lesions in the anterior chamber with signs of anterior uveitis. There was no history of ocular injury or tuberculosis in any patients. Six weeks after subconjunctival steroid injection, all patients achieved mean best-corrected visual acuity, which changed from 0.2 (range 0.1–0.4 to 0.5 (range 0.4–0.8, and the severity of iritis decreased. SD-OCT showed that the lesions at presentation appeared as a globular noncystic mass attached to the back of the cornea, encroaching on the angle of the eye, and attached to the anterior surface of the iris at some points.Conclusion: SD-OCT for imaging the anterior segment allowed us to exclude the cystic nature of this pearly lesion. Some similarities may exist between these pearly lesions and superficial phlyctenular keratitis, which may support the immunological and inflammatory origin of these lesions.Keywords: pearl-like lesions, anterior chamber, phlycten, anterior segment OCT

  15. Visual art and visual perception

    NARCIS (Netherlands)

    Koenderink, Jan J.

    2015-01-01

    Visual art and visual perception ‘Visual art’ has become a minor cul-de-sac orthogonal to THE ART of the museum directors and billionaire collectors. THE ART is conceptual, instead of visual. Among its cherished items are the tins of artist’s shit (Piero Manzoni, 1961, Merda d’Artista) “worth their

  16. [Compressive optic neuropathy related to an anterior clinoid mucocele].

    Science.gov (United States)

    Arnavielle, S; Vignal-Clermont, C; Galatoire, O; Jacomet, P-V; Klap, P; Boissonnet, H; Berges, O; Morax, S

    2010-03-01

    Nasal sinus mucoceles are an uncommon cause of painful optic neuropathy. We report the case of a patient presenting an acute compressive optic neuropathy related to an anterior clinoid mucocele. The diagnosis was mainly made with CT and MRI, and the patient was treated with endoscopic endonasal transseptal surgery 10 days after the beginning of the disorder. Visual recovery was complete 3 days later. We review the literature on the etiologies of this type of pathology, the work-up, and the possible treatments.

  17. Graves' disease presenting as unilateral anterior ischaemic optic neuropathy.

    Science.gov (United States)

    Monigari, Naresh; Deshpande, Anirudda; Nalabothu, Murali; Rao, Shilpa

    2014-03-19

    We report a case of a 28-year-old man who presented with 1-day history of sudden diminution of vision in the right eye. Examination showed unilateral exophthalmos with restricted eyeball movement on upward gaze in the right eye. MRI of the orbit showed no evidence of compression of the optic nerve on the right side. Visual-evoked potential showed prolonged P100 in the right eye. Fundus examination revealed swollen optic disc and para papillary nerve fibre layer splinter haemorrhages with corresponding altitudinal field defect on perimetry suggestive of anterior ischaemic optic neuropathy.

  18. Anterior Ischemic Optic Neuropathy as a Manifestation of HELLP Syndrome

    Directory of Open Access Journals (Sweden)

    Boby Varkey Maramattom

    2014-01-01

    Full Text Available Thrombotic microangiopathies (TMAs are a group of disorders characterized by occurrence of thrombi of fibrin and/or platelets with microvascular occlusion and organ ischemia especially the kidney and brain. Hemolysis with a microangiopathic blood smear, elevated liver enzymes, and low platelet count (HELLP syndrome is a type of TMA peculiar to pregnancy and may be associated with neurological complications. Visual complications in HELLP are usually related to cortical blindness. We present the first case of HELLP associated with bilateral anterior ischemic optic neuropathy (AION and blindness which resolved with plasma exchange.

  19. Differential involvement of the anterior temporal lobes in famous people semantics

    Directory of Open Access Journals (Sweden)

    Georges Chedid

    2016-08-01

    Full Text Available The ability to recognize a famous person occurs through semantic memory. Previous neuroimaging studies have shown that the anterior temporal lobes (ATLs are involved in the recognition of famous people. However, it is still a matter of debate whether the semantic processing of names or pictures of famous people has an impact on the activation of ATLs. The aim of this study was to explore the pattern of activation associated with a semantic processing of famous people based on face and written name stimuli. Fifteen healthy young individuals participated in our fMRI study, in which they were asked to perform a semantic categorization judgement task, based on profession, of visually presented pictures and names of famous people. Neuroimaging findings showed a common pattern of activation for faces and names mainly involving the inferior frontal regions, the posterior temporal lobe, the visual cortex and the anterior temporal lobes. We found that the comparison names vs. pictures lead to significant activation in the anterior superior temporal gyrus. On the other hand, faces vs. names seemed associated with increased activation in the medial ATL. Moreover, our results demonstrated that the functional connectivity network anchored to the medial ATL, compared to the anterior STG, is more connected to the bilateral occipital lobe and fusiform gyrus that are regions implicated in the visual system and visual processing of faces. This study provides critical evidence of the differential involvement of ATL regions in semantics of famous people.

  20. 7.1 T MRI to Assess the Anterior Segment of the Eye

    NARCIS (Netherlands)

    Langner, Soenke; Martin, Heiner; Terwee, Thom; Koopmans, Steven A.; Krueger, Paul C.; Hosten, Norbert; Schmitz, Klaus-Peter; Guthoff, Rudolf F.; Stachs, Oliver

    2010-01-01

    PURPOSE. Visualization of the anterior segment and biometric evaluation of the entire crystalline lens pose significant challenges for imaging techniques because of tissue-induced distortion artifacts. The present study was conducted to demonstrate the advantages of high-resolution magnetic resonanc

  1. Flow visualization

    CERN Document Server

    Merzkirch, Wolfgang

    1974-01-01

    Flow Visualization describes the most widely used methods for visualizing flows. Flow visualization evaluates certain properties of a flow field directly accessible to visual perception. Organized into five chapters, this book first presents the methods that create a visible flow pattern that could be investigated by visual inspection, such as simple dye and density-sensitive visualization methods. It then deals with the application of electron beams and streaming birefringence. Optical methods for compressible flows, hydraulic analogy, and high-speed photography are discussed in other cha

  2. Visual neuroscience research in China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Historically,vision research in China was one of a few distinct research programs within the Chinese Academy of Sciences(CAS).With improved funding opportunities and research environment in neuroscience,vision research at several research institutes within the academy has made significant progress not only in the quantity of publications,but also in the quality of the work.Based on our own expertise,this review is mainly focused on the findings that have advanced the understanding of visual processing in the central visual pathway,visual perceptual learning,visual development and eye diseases.

  3. Making Memories: The Development of Long-Term Visual Knowledge in Children with Visual Agnosia

    OpenAIRE

    Tiziana Metitieri; Carmen Barba; Simona Pellacani; Maria Pia Viggiano; Renzo Guerrini

    2013-01-01

    There are few reports about the effects of perinatal acquired brain lesions on the development of visual perception. These studies demonstrate nonseverely impaired visual-spatial abilities and preserved visual memory. Longitudinal data analyzing the effects of compromised perceptions on long-term visual knowledge in agnosics are limited to lesions having occurred in adulthood. The study of children with focal lesions of the visual pathways provides a unique opportunity to assess the developme...

  4. Action initiation in the human dorsal anterior cingulate cortex.

    Directory of Open Access Journals (Sweden)

    Lakshminarayan Srinivasan

    Full Text Available The dorsal anterior cingulate cortex (dACC has previously been implicated in processes that influence action initiation. In humans however, there has been little direct evidence connecting dACC to the temporal onset of actions. We studied reactive behavior in patients undergoing therapeutic bilateral cingulotomy to determine the immediate effects of dACC ablation on action initiation. In a simple reaction task, three patients were instructed to respond to a specific visual cue with the movement of a joystick. Within minutes of dACC ablation, the frequency of false starts increased, where movements occurred prior to presentation of the visual cue. In a decision making task with three separate patients, the ablation effect on action initiation persisted even when action selection was intact. These findings suggest that human dACC influences action initiation, apart from its role in action selection.

  5. Optic nerve, superior colliculus, visual thalamus, and primary visual cortex of the northern elephant seal (Mirounga angustirostris) and California sea lion (Zalophus californianus).

    Science.gov (United States)

    Turner, Emily C; Sawyer, Eva K; Kaas, Jon H

    2017-02-11

    The northern elephant seal (Mirounga angustirostris) and California sea lion (Zalophus californianus) are members of a diverse clade of carnivorous mammals known as pinnipeds. Pinnipeds are notable for their large, ape-sized brains, yet little is known about their central nervous system. Both the northern elephant seal and California sea lion spend most of their lives at sea, but each also spends time on land to breed and give birth. These unique coastal niches may be reflected in specific evolutionary adaptations to their sensory systems. Here, we report on components of the visual pathway in these two species. We found evidence for two classes of myelinated fibers within the pinniped optic nerve, those with thick myelin sheaths (elephant seal: 9%, sea lion: 7%) and thin myelin sheaths (elephant seal: 91%, sea lion: 93%). In order to investigate the architecture of the lateral geniculate nucleus, superior colliculus, and primary visual cortex, we processed brain sections from seal and sea lion pups for Nissl substance, cytochrome oxidase, and vesicular glutamate transporters. As in other carnivores, the dorsal lateral geniculate nucleus consisted of three main layers, A, A1, and C, while each superior colliculus similarly consisted of seven distinct layers. The sea lion visual cortex is located at the posterior side of cortex between the upper and lower banks of the postlateral sulcus, while the elephant seal visual cortex extends far more anteriorly along the dorsal surface and medial wall. These results are relevant to comparative studies related to the evolution of large brains.

  6. Visual Servoing

    OpenAIRE

    Chaumette, Francois; Hutchinson, Seth; Corke, Peter

    2016-01-01

    International audience; This chapter introduces visual servo control, using computer vision data in the servo loop to control the motion of a robot. We first describe the basic techniques that are by now well established in the field. We give a general overview of the formulation of the visual servo control problem, and describe the two archetypal visual servo control schemes: image-based and pose-based visual servo control. We then discuss performance and stability issues that pertain to the...

  7. Unilateral anterior uveitis complicating zoledronic acid therapy in breast cancer

    Directory of Open Access Journals (Sweden)

    El Saghir Nagi S

    2005-12-01

    Full Text Available Abstract Background Zoledronic acid is very widely used in patients with metastatic bone disease and osteoporosis. Only one case of bilateral uveitis was recently reported related to its use. Case presentation We report the first case of severe unilateral anterior uveitis in a patient with breast cancer and an intraocular lens. Following zoledronic acid infusion, the patient developed severe and dramatic right eye pain with decreased visual acuity within 24 hours and was found to have a fibrinous anterior uveitis of moderate severity The patient was treated with topical prednisone and atropine eyedrops and recovered slowly over several months. Conclusion Internists, oncologists, endocrinologists, and ophtalmologists should be aware of uveitis as a possible complication of zoledronic acid therapy. Patients should be instructed to report immediately to their physicians and treatment with topical prednisone and atropine eyedrops should be instituted immediately at the onset of symptoms. This report documents anterior uveitis as a complication of zoledronic acid therapy. This reaction could be an idiosyncratic one but further research may shed more light on the etiology.

  8. Abnormal brain activation in neurofibromatosis type 1: a link between visual processing and the default mode network.

    Directory of Open Access Journals (Sweden)

    Inês R Violante

    Full Text Available Neurofibromatosis type 1 (NF1 is one of the most common single gene disorders affecting the human nervous system with a high incidence of cognitive deficits, particularly visuospatial. Nevertheless, neurophysiological alterations in low-level visual processing that could be relevant to explain the cognitive phenotype are poorly understood. Here we used functional magnetic resonance imaging (fMRI to study early cortical visual pathways in children and adults with NF1. We employed two distinct stimulus types differing in contrast and spatial and temporal frequencies to evoke relatively different activation of the magnocellular (M and parvocellular (P pathways. Hemodynamic responses were investigated in retinotopically-defined regions V1, V2 and V3 and then over the acquired cortical volume. Relative to matched control subjects, patients with NF1 showed deficient activation of the low-level visual cortex to both stimulus types. Importantly, this finding was observed for children and adults with NF1, indicating that low-level visual processing deficits do not ameliorate with age. Moreover, only during M-biased stimulation patients with NF1 failed to deactivate or even activated anterior and posterior midline regions of the default mode network. The observation that the magnocellular visual pathway is impaired in NF1 in early visual processing and is specifically associated with a deficient deactivation of the default mode network may provide a neural explanation for high-order cognitive deficits present in NF1, particularly visuospatial and attentional. A link between magnocellular and default mode network processing may generalize to neuropsychiatric disorders where such deficits have been separately identified.

  9. Incidental Anterior Cruciate Ligament Calcification: Case Report.

    Science.gov (United States)

    Hayashi, Hisami; Fischer, Hans

    2016-03-01

    The calcification of knee ligaments is a finding noted only in a handful of case reports. The finding of an anterior cruciate ligament calcification has been reported once in the literature. Comparable studies involving the posterior cruciate ligament, medial collateral ligament and an ossicle within the anterior cruciate ligament are likewise discussed in reports of symptomatic patients. We report a case of incidentally discovered anterior cruciate ligament calcification. We discuss the likely etiology and clinical implications of this finding.

  10. Data visualization

    CERN Document Server

    Azzam, Tarek

    2013-01-01

    Do you communicate data and information to stakeholders? In Part 1, we introduce recent developments in the quantitative and qualitative data visualization field and provide a historical perspective on data visualization, its potential role in evaluation practice, and future directions. Part 2 delivers concrete suggestions for optimally using data visualization in evaluation, as well as suggestions for best practices in data visualization design. It focuses on specific quantitative and qualitative data visualization approaches that include data dashboards, graphic recording, and geographic information systems (GIS). Readers will get a step-by-step process for designing an effective data dashboard system for programs and organizations, and various suggestions to improve their utility.

  11. Toxic Anterior Segment Syndrome (TASS

    Directory of Open Access Journals (Sweden)

    Özlem Öner

    2011-12-01

    Full Text Available Toxic anterior segment syndrome (TASS is a sterile intraocular inflammation caused by noninfectious substances, resulting in extensive toxic damage to the intraocular tissues. Possible etiologic factors of TASS include surgical trauma, bacterial endotoxin, intraocular solutions with inappropriate pH and osmolality, preservatives, denatured ophthalmic viscosurgical devices (OVD, inadequate sterilization, cleaning and rinsing of surgical devices, intraocular lenses, polishing and sterilizing compounds which are related to intraocular lenses. The characteristic signs and symptoms such as blurred vision, corneal edema, hypopyon and nonreactive pupil usually occur 24 hours after the cataract surgery. The differential diagnosis of TASS from infectious endophthalmitis is important. The main treatment for TASS formation is prevention. TASS is a cataract surgery complication that is more commonly seen nowadays. In this article, the possible underlying causes as well as treatment and prevention methods of TASS are summarized. (Turk J Oph thal mol 2011; 41: 407-13

  12. Quantized Visual Awareness

    Directory of Open Access Journals (Sweden)

    W Alexander Escobar

    2013-11-01

    Full Text Available The proposed model holds that, at its most fundamental level, visual awareness is quantized. That is to say that visual awareness arises as individual bits of awareness through the action of neural circuits with hundreds to thousands of neurons in at least the human striate cortex. Circuits with specific topologies will reproducibly result in visual awareness that correspond to basic aspects of vision like color, motion and depth. These quanta of awareness (qualia are produced by the feedforward sweep that occurs through the geniculocortical pathway but are not integrated into a conscious experience until recurrent processing from centers like V4 or V5 select the appropriate qualia being produced in V1 to create a percept. The model proposed here has the potential to shift the focus of the search for visual awareness to the level of microcircuits and these likely exist across the kingdom Animalia. Thus establishing qualia as the fundamental nature of visual awareness will not only provide a deeper understanding of awareness, but also allow for a more quantitative understanding of the evolution of visual awareness throughout the animal kingdom.

  13. Evaluation of anterior segment parameters in patients with pseudoexfoliation syndrome using Scheimpflug imaging

    Directory of Open Access Journals (Sweden)

    Alime Gunes

    2016-06-01

    Full Text Available ABSTRACT Purpose: To evaluate anterior segment parameters in patients with pseudoexfoliation syndrome (PXS using Scheimpflug imaging. Methods: Forty-three PXS patients and 43 healthy control subjects were included in this cross-sectional study. All participants underwent a detailed ophthalmologic examination. Anterior segment parameters were measured using a Scheimpflug system. Results: Considering the PXS and control groups, the mean corneal thicknesses at the apex point (536 ± 31 and 560 ± 31 µm, respectively, p=0.001, at the center of the pupil (534 ± 31 and 558 ± 33 µm, respectively, p=0.001, and at the thinnest point (528 ± 30 and 546 ± 27 µm, respectively, p=0.005 were significantly thinner in PXS patients. Visual acuity was significantly lower (0.52 ± 0.37 versus 0.88 ± 0.23, p<0.001 and axial length was significantly longer (23.9 ± 0.70 mm versus 23.2 ± 0.90 mm, p=0.001 in the PXS eyes than in the control eyes. There were no statistically significant differences in the mean values of keratometry, anterior chamber angle, anterior chamber depth, corneal volume, and anterior chamber volume between the PXS and control eyes. Conclusions: The patients with PXS had thinner corneas, worse visual acuity, and longer axial length compared with those in the healthy controls.

  14. Mild toxic anterior segment syndrome mimicking delayed onset toxic anterior segment syndrome after cataract surgery

    Directory of Open Access Journals (Sweden)

    Su-Na Lee

    2014-01-01

    Full Text Available Toxic anterior segment syndrome (TASS is an acute sterile postoperative anterior segment inflammation that may occur after anterior segment surgery. I report herein a case that developed mild TASS in one eye after bilateral uneventful cataract surgery, which was masked during early postoperative period under steroid eye drop and mimicking delayed onset TASS after switching to weaker steroid eye drop.

  15. Visual Awareness Is Limited by the Representational Architecture of the Visual System.

    Science.gov (United States)

    Cohen, Michael A; Nakayama, Ken; Konkle, Talia; Stantić, Mirta; Alvarez, George A

    2015-11-01

    Visual perception and awareness have strict limitations. We suggest that one source of these limitations is the representational architecture of the visual system. Under this view, the extent to which items activate the same neural channels constrains the amount of information that can be processed by the visual system and ultimately reach awareness. Here, we measured how well stimuli from different categories (e.g., faces and cars) blocked one another from reaching awareness using two distinct paradigms that render stimuli invisible: visual masking and continuous flash suppression. Next, we used fMRI to measure the similarity of the neural responses elicited by these categories across the entire visual hierarchy. Overall, we found strong brain-behavior correlations within the ventral pathway, weaker correlations in the dorsal pathway, and no correlations in early visual cortex (V1-V3). These results suggest that the organization of higher level visual cortex constrains visual awareness and the overall processing capacity of visual cognition.

  16. Anterior urethral diverticulum: A rare presentation

    Directory of Open Access Journals (Sweden)

    Annavarupu Gopalkrishna

    2016-01-01

    Full Text Available Congenital anomalies of the urogenital tract are the most common anomalies found in the foetus, neonates and infants, but anterior urethral valves and diverticula are rare. Here, we present a case with congenital anterior urethral diverticulum associated with patent ductus arteriosus and polydactyly.

  17. Anterior segment complications of retinal photocoagulation.

    Science.gov (United States)

    Kanski, J J

    1975-03-01

    Seven patients had anterior segment complications following xenon arc retinal photocoagulation. Irreversible keratopathy was induced in two cases; all patients showed evidence of iris injury. The absorption of radiation by the iris was considered the main factor in producing overheating of the anterior segment.

  18. Anterior cervical hypertrichosis: a sporadic case.

    Science.gov (United States)

    Bostan, Sezen; Yaşar, Şirin; Serdar, Zehra Aşiran; Gizlenti, Sevda

    2016-03-01

    Anterior cervical hypertrichosis is a very rare form of primary localized hypertrichosis. It consists of a tuft of terminal hair on the anterior neck just above the laryngeal prominence. The etiology is still unknown. In this article, we reported a 15-year-old female patient who presented to our clinic with a complaint of hypertrichosis on the anterior aspect of the neck for the last five years. Her past medical history revealed no pathology except for vesicoureteral reflux. On the basis of clinical presentation, our patient was diagnosed with anterior cervical hypertrichosis and she was considered to be a sporadic case due to lack of other similar cases in familial history. To date, 33 patients with anterior cervical hypertrichosis have been reported. Anterior cervical hypertrichosis can be associated with other abnormalities, but it frequently presents as an isolated defect (70%). The association of vesicoureteral reflux and anterior cervical hypertrichosis which was observed in our patient might be coincidental. So far, no case of anterior cervical hypertrichosis associated with vesicoureteral reflux has been reported in the literature.

  19. Anterior corneal and internal contributions to peripheral aberrations of human eyes

    Science.gov (United States)

    Atchison, David A.

    2004-03-01

    Anterior corneal and internal component contributions to overall peripheral aberrations of five human eyes were determined, based on corneal topography and overall aberration measurements. Anterior corneal position and orientation (tilt) were referenced to the line of sight. Ray tracing was performed through the anterior cornea for 6-mm-diameter pupils at angles out to 40° in both the temporal and the nasal visual fields. In general, both component and overall Zernike aberrations were greater for the nasal than for the temporal visual field. In general, the anterior corneal aberration components were considerably higher than the overall aberrations across the visual field and were balanced to a considerable degree by the internal ocular aberration components. The component and overall levels of Zernike third-order aberrations showed linear trends away from the fixation axis, and the component levels of Zernike fourth-order aberrations showed quadratic trends away from the fixation axis. The second-order, but not higher-order, aberration components were susceptible to the choice of image radius of curvature, while disregarding corneal position and orientation affected second- and higher-order aberration components.

  20. Auditory and visual connectivity gradients in frontoparietal cortex.

    Science.gov (United States)

    Braga, Rodrigo M; Hellyer, Peter J; Wise, Richard J S; Leech, Robert

    2017-01-01

    A frontoparietal network of brain regions is often implicated in both auditory and visual information processing. Although it is possible that the same set of multimodal regions subserves both modalities, there is increasing evidence that there is a differentiation of sensory function within frontoparietal cortex. Magnetic resonance imaging (MRI) in humans was used to investigate whether different frontoparietal regions showed intrinsic biases in connectivity with visual or auditory modalities. Structural connectivity was assessed with diffusion tractography and functional connectivity was tested using functional MRI. A dorsal-ventral gradient of function was observed, where connectivity with visual cortex dominates dorsal frontal and parietal connections, while connectivity with auditory cortex dominates ventral frontal and parietal regions. A gradient was also observed along the posterior-anterior axis, although in opposite directions in prefrontal and parietal cortices. The results suggest that the location of neural activity within frontoparietal cortex may be influenced by these intrinsic biases toward visual and auditory processing. Thus, the location of activity in frontoparietal cortex may be influenced as much by stimulus modality as the cognitive demands of a task. It was concluded that stimulus modality was spatially encoded throughout frontal and parietal cortices, and was speculated that such an arrangement allows for top-down modulation of modality-specific information to occur within higher-order cortex. This could provide a potentially faster and more efficient pathway by which top-down selection between sensory modalities could occur, by constraining modulations to within frontal and parietal regions, rather than long-range connections to sensory cortices. Hum Brain Mapp 38:255-270, 2017. © 2016 Wiley Periodicals, Inc.

  1. Meningioma Causing Visual Impairment: Outcomes and Toxicity After Intensity Modulated Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Maclean, Jillian, E-mail: jillian.maclean@uclh.nhs.uk [Radiotherapy Department, University College London Hospital, London (United Kingdom); Fersht, Naomi [Radiotherapy Department, University College London Hospital, London (United Kingdom); Bremner, Fion [Neuro-Ophthalmology Department, National Hospital for Neurology and Neurosurgery, London (United Kingdom); Stacey, Chris; Sivabalasingham, Suganya [Radiotherapy Department, University College London Hospital, London (United Kingdom); Short, Susan [Radiotherapy Department, University College London Hospital, London (United Kingdom); Leeds Institute of Molecular Medicine, St James University Hospital, Leeds (United Kingdom)

    2013-03-15

    Purpose: To evaluate ophthalmologic outcomes and toxicity of intensity modulated radiation therapy (IMRT) in patients with meningiomas causing visual deficits. Methods and Materials: A prospective observational study with formal ophthalmologic and clinical assessment of 30 consecutive cases of meningioma affecting vision treated with IMRT from 2007 to 2011. Prescriptions were 50.4 Gy to mean target dose in 28 daily fractions. The median follow-up time was 28 months. Twenty-six meningiomas affected the anterior visual pathway (including 3 optic nerve sheath meningiomas); 4 were posterior to the chiasm. Results: Vision improved objectively in 12 patients (40%). Improvements were in visual field (5/16 patients), color vision (4/9 patients), acuity (1/15 patients), extraocular movements (3/11 patients), ptosis (1/5 patients), and proptosis (2/6 patients). No predictors of clinical response were found. Two patients had minor reductions in tumor dimensions on magnetic resonance imaging, 1 patient had radiological progression, and the other patients were stable. One patient experienced grade 2 keratitis, 1 patient had a minor visual field loss, and 5 patients had grade 1 dry eye. Conclusion: IMRT is an effective method for treating meningiomas causing ophthalmologic deficits, and toxicity is minimal. Thorough ophthalmologic assessment is important because clinical responses often occur in the absence of radiological change.

  2. Selective importance of the rat anterior thalamic nuclei for configural learning involving distal spatial cues.

    Science.gov (United States)

    Dumont, Julie R; Amin, Eman; Aggleton, John P

    2014-01-01

    To test potential parallels between hippocampal and anterior thalamic function, rats with anterior thalamic lesions were trained on a series of biconditional learning tasks. The anterior thalamic lesions did not disrupt learning two biconditional associations in operant chambers where a specific auditory stimulus (tone or click) had a differential outcome depending on whether it was paired with a particular visual context (spot or checkered wall-paper) or a particular thermal context (warm or cool). Likewise, rats with anterior thalamic lesions successfully learnt a biconditional task when they were reinforced for digging in one of two distinct cups (containing either beads or shredded paper), depending on the particular appearance of the local context on which the cup was placed (one of two textured floors). In contrast, the same rats were severely impaired at learning the biconditional rule to select a specific cup when in a particular location within the test room. Place learning was then tested with a series of go/no-go discriminations. Rats with anterior thalamic nuclei lesions could learn to discriminate between two locations when they were approached from a constant direction. They could not, however, use this acquired location information to solve a subsequent spatial biconditional task where those same places dictated the correct choice of digging cup. Anterior thalamic lesions produced a selective, but severe, biconditional learning deficit when the task incorporated distal spatial cues. This deficit mirrors that seen in rats with hippocampal lesions, so extending potential interdependencies between the two sites.

  3. Extraction of Iron from the Rabbit Anterior Chamber with Reverse Iontophoresis

    Directory of Open Access Journals (Sweden)

    Shoubin Sun

    2015-01-01

    Full Text Available Ocular siderosis is a common eye disease caused by retention of an iron-containing intraocular foreign body in the eye. Iron-containing intraocular foreign bodies may cause severe inflammatory reaction and affect visual function. Currently the optimal treatment method of ocular siderosis is a moot point. This study used the reverse iontophoresis technique to noninvasively extract iron from the rabbit anterior chamber. By slit lamp observation and histological examination, reverse iontophoresis treatment has a good effect on ocular siderosis. Reverse iontophoresis seems to be a noninvasive and promising approach to extract iron from the anterior chamber to treat ocular siderosis.

  4. Visualization Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Evaluates and improves the operational effectiveness of existing and emerging electronic warfare systems. By analyzing and visualizing simulation results...

  5. Traffic Visualization

    DEFF Research Database (Denmark)

    Picozzi, Matteo; Verdezoto, Nervo; Pouke, Matti;

    2013-01-01

    In this paper, we present a space-time visualization to provide city's decision-makers the ability to analyse and uncover important "city events" in an understandable manner for city planning activities. An interactive Web mashup visualization is presented that integrates several visualization...... techniques to give a rapid overview of traffic data. We illustrate our approach as a case study for traffic visualization systems, using datasets from the city of Oulu that can be extended to other city planning activities. We also report the feedback of real users (traffic management employees, traffic police...

  6. ANTERIOR KNEE PAIN IN TRANSTENDINOUS AND PARATENDINOUS APPROACHES OF TIBIAL INTERLOCKING NAIL: A COMPARATIVE STUDY

    Directory of Open Access Journals (Sweden)

    Gyaneshwar

    2014-07-01

    Full Text Available BACKGROUND: Anterior knee pain has been described as the most common complication after intramedullary nailing of fracture shaft of tibia. Dissection of the patellar tendon and its sheath during transtendinous nailing is thought to be as one of the contributing causes of chronic anterior knee pain. The purpose of this prospective, randomized study was to compare the incidence of anterior knee pain after intramedullary nailing of a tibial shaft fracture with transtendinous and paratendinous incision technique. MATERIAL AND METHODS: From April 2012 to October 2013 eighty patients with closed tibial shaft fractures were admitted and treated in our institution. Patients were randomized for treatment with paratendinous or transtendinous nailing (as 24 patients did not complete their follow up or were lost in follow up, so 56 patients were analyzed finally. For assessment we used visual analogue scales to report the level of anterior knee pain. The scales described by Lysholm and Gillquist and by Tegner et al., were also used to quantitate the functional results. RESULTS: 12 of the 28 (42% patients treated with transtendinous nailing. reported anterior knee pain whereas 8 patients out of 28 (28%, in which paratendinous technique was used had persistent anterior knee pain after minimum final follow up of 24 weeks, with no significant statistical difference. The Lysholm, Tegner functional scoring systems showed a significant difference between the two groups. CONCLUSION: Compared with a transtendinous approach, a paratendinous approach for nail insertion does not reduce the incidence of chronic anterior knee pain or functional impairment after intramedullary nailing of a tibial shaft fracture. In long term, anterior knee pain seems to disappear from many patients. Since our study is small and have short duration of follow up, further larger studies and long duration of follow up is needed to establish the results

  7. Ocular Coherence Tomography in the Evaluation of Anterior Eye Injuries in Space Flight

    Science.gov (United States)

    Fer, Dan M.; Law, Jennifer; Wells, Julia

    2017-01-01

    While Ocular Coherence Tomography (OCT) is not a first-line modality to evaluate anterior eye structures terrestrially, it is a resource already available on the International Space Station (ISS) that can be used in medical contingencies that involve the anterior eye. With remote guidance and subject matter expert (SME) support from the ground, a minimally trained crewmember can now use OCT to evaluate anterior eye pathologies on orbit. OCT utilizes low-coherence interferometry to produce detailed cross-sectional and 3D images of the eye in real time. Terrestrially, it has been used to evaluate macular pathologies and glaucoma. Since 2013, OCT has been used onboard the ISS as one part of a suite of hardware to evaluate the Visual Impairment/Intracranial Pressure risk faced by astronauts, specifically assessing changes in the retina and choroid during space flight. The Anterior Segment Module (ASM), an add-on lens, was also flown for research studies, providing an opportunity to evaluate the anterior eye in real time if clinically indicated. Anterior eye pathologies that could be evaluated using OCT were identified. These included corneal abrasions and ulcers, scleritis, and acute angle closure glaucoma. A remote guider script was written to provide ground specialists with step-by-step instructions to guide ISS crewmembers, who do not get trained on the ASM, to evaluate the anterior eye. The instructions were tested on novice subjects and/or operators, whose feedback was incorporated iteratively. The final remote guider script was reviewed by SME optometrists and NASA flight surgeons. The novel application of OCT technology to space flight allows for the acquisition of objective data to diagnose anterior eye pathologies when other modalities are not available. This demonstrates the versatility of OCT and highlights the advantages of using existing hardware and remote guidance skills to expand clinical capabilities in space flight.

  8. Smelling directions: olfaction modulates ambiguous visual motion perception.

    Science.gov (United States)

    Kuang, Shenbing; Zhang, Tao

    2014-07-23

    Senses of smells are often accompanied by simultaneous visual sensations. Previous studies have documented enhanced olfactory performance with concurrent presence of congruent color- or shape- related visual cues, and facilitated visual object perception when congruent smells are simultaneously present. These visual object-olfaction interactions suggest the existences of couplings between the olfactory pathway and the visual ventral processing stream. However, it is not known if olfaction can modulate visual motion perception, a function that is related to the visual dorsal stream. We tested this possibility by examining the influence of olfactory cues on the perceptions of ambiguous visual motion signals. We showed that, after introducing an association between motion directions and olfactory cues, olfaction could indeed bias ambiguous visual motion perceptions. Our result that olfaction modulates visual motion processing adds to the current knowledge of cross-modal interactions and implies a possible functional linkage between the olfactory system and the visual dorsal pathway.

  9. Differential Involvement of the Anterior Temporal Lobes in Famous People Semantics

    Science.gov (United States)

    Chedid, Georges; Wilson, Maximiliano A.; Provost, Jean-Sebastien; Joubert, Sven; Rouleau, Isabelle; Brambati, Simona M.

    2016-01-01

    The ability to recognize a famous person occurs through semantic memory. Previous neuroimaging studies have shown that the anterior temporal lobes (ATLs) are involved in the recognition of famous people. However, it is still a matter of debate whether the semantic processing of names or pictures of famous people has an impact on the activation of ATLs. The aim of this study was to explore the pattern of activation associated with a semantic processing of famous people based on face and written name stimuli. Fifteen healthy young individuals participated in our fMRI study, in which they were asked to perform a semantic categorization judgment task, based on profession, of visually presented pictures, and names of famous people. Neuroimaging findings showed a common pattern of activation for faces and names mainly involving the inferior frontal regions, the posterior temporal lobe, the visual cortex, and the ATLs. We found that the comparison names vs. pictures lead to significant activation in the anterior superior temporal gyrus. On the other hand, faces vs. names seemed associated with increased activation in the medial ATL. Moreover, our results demonstrated that the functional connectivity network anchored to the medial ATL, compared to the anterior STG, is more connected to the bilateral occipital lobe and fusiform gyrus that are regions implicated in the visual system and visual processing of faces. This study provides critical evidence of the differential involvement of ATL regions in semantics of famous people. PMID:27625630

  10. Visual search

    NARCIS (Netherlands)

    Toet, A.; Bijl, P.

    2003-01-01

    Visual search, with or without the aid of optical or electro-optical instruments, plays a significant role in various types of military and civilian operations (e.g., reconnaissance, surveillance, and search and rescue). Advance knowledge of human visual search and target acquisition performance is

  11. Visual Thinking.

    Science.gov (United States)

    Arnheim, Rudolf

    Based on the more general principle that all thinking (including reasoning) is basically perceptual in nature, the author proposes that visual perception is not a passive recording of stimulus material but an active concern of the mind. He delineates the task of visually distinguishing changes in size, shape, and position and points out the…

  12. Mini-open anterior lumbar interbody fusion.

    Science.gov (United States)

    Gandhoke, Gurpreet S; Ricks, Christian; Tempel, Zachary; Zuckerbraun, Brian; Hamilton, D Kojo; Okonkwo, David O; Kanter, Adam S

    2016-07-01

    In deformity surgery, anterior lumbar interbody fusion provides excellent biomechanical support, creates a broad surface area for arthrodesis, and induces lordosis in the lower lumbar spine. Preoperative MRI, plain radiographs, and, when available, CT scan should be carefully assessed for sacral slope as it relates to pubic symphysis, position of the great vessels (especially at L4/5), disc space height, or contraindication to an anterior approach. This video demonstrates the steps in an anterior surgical procedure with minimal open exposure. The video can be found here: https://youtu.be/r3bC4_vu1hQ .

  13. How I do it: Anterior pull-through tympanoplasty for anterior eardrum perforations.

    Science.gov (United States)

    Harris, Jeffrey P; Wong, Yu-Tung; Yang, Tzong-Hann; Miller, Mia

    2016-01-01

    Conclusions This technique is offered as a convenient and reliable method for cases with anterior TM perforation and inadequate anterior remnant. Objectives Chronic otitis media surgery is one of the most common procedures in otology. Anterior tympanic membrane (TM) perforation with inadequate anterior remnant is associated with higher rates of graft failure. It was the goal of this series to evaluate the anatomical and functional outcomes of a modified underlay myringoplasty technique-the anterior pull-through method. Materials and methods In a retrospective clinical study, 13 patients with anterior TM perforations with inadequate anterior remnants underwent tympanoplasty with anterior pull-through technique. The anterior tip of the temporalis fascia was pulled through and secured in a short incision lateral to the anterior part of the annulus. Data on graft take rate, pre-operative, and post-operative hearing status were analyzed. Results A graft success rate of 84.6% (11 out of 13) was achieved, without lateralization, blunting, atelectasia, or epithelial pearls. The air-bone gap was 21.5 ± 6.8 dB before intervention and 11.75 ± 5.7 dB after surgery (p = 0.003).

  14. Quadriceps muscle contraction protects the anterior cruciate ligament during anterior tibial translation.

    Science.gov (United States)

    Aune, A K; Cawley, P W; Ekeland, A

    1997-01-01

    The proposed skiing injury mechanism that suggests a quadriceps muscle contraction can contribute to anterior cruciate ligament rupture was biomechanically investigated. The effect of quadriceps muscle force on a knee specimen loaded to anterior cruciate ligament failure during anterior tibial translation was studied in a human cadaveric model. In both knees from six donors, average age 41 years (range, 31 to 65), the joint capsule and ligaments, except the anterior cruciate ligament, were cut. The quadriceps tendon, patella, patellar tendon, and menisci were left intact. One knee from each pair was randomly selected to undergo destructive testing of the anterior cruciate ligament by anterior tibial translation at a displacement rate of 30 mm/sec with a simultaneously applied 889 N quadriceps muscle force. The knee flexion during testing was 30 degrees. As a control, the contralateral knee was loaded correspondingly, but only 5 N of quadriceps muscle force was applied. The ultimate load for the knee to anterior cruciate ligament failure when tested with 889 N quadriceps muscle force was 22% +/- 18% higher than that of knees tested with 5 N of force. The linear stiffness increased by 43% +/- 30%. These results did not support the speculation that a quadriceps muscle contraction contributes to anterior cruciate ligament failure. In this model, the quadriceps muscle force protected the anterior cruciate ligament from injury during anterior tibial translation.

  15. Ophthalmomyiasis interna anterior in a dog: keratotomy and extraction of a Cuterebra sp. larva.

    Science.gov (United States)

    Edelmann, Michele L; Lucio-Forster, Araceli; Kern, Thomas J; Bowman, Dwight D; Ledbetter, Eric C

    2014-11-01

    A 1-year-old female spayed mixed-breed dog was presented for evaluation of acute onset of lethargy and blepharospasm OD. Slit-lamp biomicroscopy revealed a segmented larva embedded in the inferonasal iris. Moderate anterior uveitis was present. After pharmacologic dilation, mild vitreal hemorrhage and chorioretinal migration tracks were identified. The dog was treated empirically for uveitis for 5 days, after which a keratotomy and larval foreign body extraction was performed. The dog recovered uneventfully from intraocular surgery and remained visual and comfortable. Parasite evaluation confirmed the larva to be a Cuterebra sp. To the authors' knowledge, this is the first report of canine ophthalmomyiasis interna anterior, and the first report of successful surgical removal from the anterior segment in a dog with preservation of vision.

  16. Feelings of warmth correlate with neural activity in right anterior insular cortex.

    Science.gov (United States)

    Olausson, H; Charron, J; Marchand, S; Villemure, C; Strigo, I A; Bushnell, M C

    2005-11-25

    The neural coding of perception can differ from that for the physical attributes of a stimulus. Recent studies suggest that activity in right anterior insular cortex may underlie thermal perception, particularly that of cold. We now examine whether this region is also important for the perception of warmth. We applied cutaneous warm stimuli on the left leg (warmth) in normal subjects (n = 7) during functional magnetic resonance imaging (fMRI). After each stimulus, subjects rated their subjective intensity of the stimulus using a visual analogue scale (VAS), and correlations were determined between the fMRI signal and the VAS ratings. We found that intensity ratings of warmth correlated with the fMRI signal in the right (contralateral to stimulation) anterior insular cortex. These results, in conjunction with previous reports, suggest that the right anterior insular cortex is important for different types of thermal perception.

  17. Guideline on anterior cruciate ligament injury

    NARCIS (Netherlands)

    D.E. Meuffels (Duncan); M.T. Poldervaart (Michelle T.); R.L. Diercks (Ron L.); A.W.F.M. Fievez (Alex W.F.M.); T.W. Patt (Thomas W.); C.P. van der Hart (Cor P.); E.R. Hammacher (Eric); F. van der Meer (Fred); E.A. Goedhart (Edwin A.); A.F. Lenssen (Anton F); S.B. Muller-Ploeger (Sabrina B); M.A. Pols (Margreet); D.B.F. Saris (Daniel)

    2012-01-01

    textabstractThe Dutch Orthopaedic Association has a long tradition of development of practical clinical guidelines. Here we present the recommendations from the multidisciplinary clinical guideline working group for anterior cruciate ligament injury. The following 8 clinical questions were formulate

  18. Care of children with anterior uveitis.

    Science.gov (United States)

    Kanski, J J

    1981-09-01

    The clinical features of 290 children with anterior uveitis are presented. The vast majority suffered from chronic uveitis. Specific uveitis entities in children include the syndrome of 'chronic iridocyclitis' in girls, heterochromic cyclitis, and pars planitis. Systemic associations include sarcoidosis, the Vogt-Harada-Koyanagi syndrome, and the seronegative arthritides (juvenile chronic arthritis, juvenile ankylosing spondylitis, psoriatic arthritis, and rarely Reiter's and Beçet's syndromes). Children with a pauciarticular onset of juvenile chronic arthritis, especially when combined with positive findings for antinuclear antibody, are at particular risk of developing chronic anterior uveitis. Most cases of chronic anterior uveitis can be controlled with topical corticosteroids. Those that are resistant to both topical and systemic corticosteroids may have to be treated with chlorambucil. The operation of lensectomy is a great advance in the management of complicated cataract. Secondary glaucoma is the most devastating complication of chronic anterior uveitis in children and responds poorly to therapy.

  19. Head positioning for anterior circulation aneurysms microsurgery

    Directory of Open Access Journals (Sweden)

    Feres Chaddad-Neto

    2014-11-01

    Full Text Available Objective To study the ideal patient's head positioning for the anterior circulation aneurysms microsurgery. Method We divided the study in two parts. Firstly, 10 fresh cadaveric heads were positioned and dissected in order to ideally expose the anterior circulation aneurysm sites. Afterwards, 110 patients were submitted to anterior circulation aneurysms microsurgery. During the surgery, the patient's head was positioned accordingly to the aneurysm location and the results from the cadaveric study. The effectiveness of the position was noted. Results We could determine mainly two patterns for head positioning for the anterior circulation aneurysms. Conclusion The best surgical exposure is related to specific head positions. The proper angle of microscopic view may minimize neurovascular injury and brain retraction.

  20. Upper anterior zone restoration with composites

    OpenAIRE

    Lamas Lara, César; CD, Docente del Área de Operatoria Dental y Endodoncia de la Facultad de Odontología de la UNMSM.; Angulo de la Vega, Giselle; CD, Alumna de la Especialidad de Rehabilitación Oral de la Facultad de Odontología de la UNMSM.

    2014-01-01

    The anterior sector problems are very common in our professional practice and became vital importance to make a suitable rehabilitation in these cases; we can not do a good rehabilitation if we do not know the basic characteristics, both aesthetic and functional. Today the composites are a valid alternative for the restoration of the anterior sector, since they offer to us a conservative and aesthetic possibility, but independently of the material to use we have to based on certain rules or p...

  1. Erlotinib-related bilateral anterior uveitis

    Science.gov (United States)

    Ali, Kashif; Kumar, Indu; Usman-Saeed, Muniba; Usman Saeed, Muhammad

    2011-01-01

    The authors report the case of a 68-year-old woman with secondary adenocarcinoma of the lungs from an unknown primary. Erlotinib was started which produced symptoms suggestive of uveitis. Erlotinib was stopped and restarted a month later at a lower dose, which resulted in severe bilateral anterior uveitis. The uveitis settled after stopping erlotinib and treatment with topical steroids and cycloplegics. To the best of the authors’ knowledge, this is the first case of erlotinib-related anterior uveitis. PMID:22694887

  2. The anterior loop of the inferior alveolar nerve. A radiographic study of panoramic radiographs and review of the literature.

    Directory of Open Access Journals (Sweden)

    Konstantinos VLASTOS

    2014-04-01

    Full Text Available The inferior alveolar nerve sometimes extends anteriorly beyond the mental foramen and runs outward, upward and backward before it reaches the mental foramen, creating what is known as the anterior loop. Placement of dental implants in this area, has a high risk of injury to the inferior alveolar nerve. Aim: This study seeks to investigate the visualization of the anterior loop on panoramic radiographs. Material and methods: 100 panoramic radiographs were analysed in terms of loop visualization. Results: Anterior loop was observed in 34% of the radiographs. Its prevalence was higher in males (70.5% and in patients between 40-60 years old (47%. In most cases the loop was located bilaterally (64.7%, while the interforaminal area was mostly edentulous (64.7%. The loop length ranged between 0.5-8 mm, with an average length of 4.37mm. Conclusions: An analysis of the findings shows that implants should be placed at least 5-8mm anteriorly to the mental foramen. According to a review of the literature, computed tomography is more accurate than panoramic radiography in identifying the anterior loop.

  3. Optic neuritis and acute anterior uveitis associated with influenza A infection: a case report

    Directory of Open Access Journals (Sweden)

    Nakagawa H

    2017-01-01

    Full Text Available Hayate Nakagawa, Hidetaka Noma, Osamu Kotake, Ryosuke Motohashi, Kanako Yasuda, Masahiko Shimura Department of Ophthalmology, Tokyo Medical University Hachioji Medical Center, Tokyo, Japan Background: A few reports have described ocular complications of influenza A infection, such as impaired ocular movement, parasympathetic ocular nerve, keratitis, macular lesion, and frosted branch angiitis. We encountered a rare case of acute anterior uveitis and optic neuritis associated with influenza A infection. Case presentation: A 70-year-old man presented with symptoms of upper respiratory tract infection. A rapid diagnostic test showed a positive result for influenza A. At the same time, he developed ocular symptoms including blurred vision with optic disk edema and hemorrhage in the left eye, and bilateral red eyes. Multiplex polymerase chain reaction performed on aqueous humor sample detected no viral infection. Visual field testing with a Goldmann perimeter showed central and paracentral scotomas in the left eye. In addition to antiviral agent (oseltamivir phosphate 75 mg, the patient was prescribed topical prednisolone acetate ophthalmic suspension eye drops every 5 hours and high-dose intravenous methylprednisolone 1,000 mg daily for 3 days. Two months later, his best-corrected visual acuity improved to 20/50 with regression of visual field defects in his left eye. Conclusion: We report a case of bilateral acute anterior uveitis and unilateral optic neuritis concomitant with influenza A infection. Topical and systemic corticosteroids were effective to resolve acute anterior uveitis and neuritis. Analysis of aqueous humor sample suggested that acute anterior uveitis and optic neuritis in this case were not caused by influenza A virus infection per se but by autoimmune mechanism. Keywords: optic neuritis, anterior uveitis, influenza virus, multiplex polymerase chain reaction

  4. Anterior Eye Imaging with Optical Coherence Tomography

    Science.gov (United States)

    Huang, David; Li, Yan; Tang, Maolong

    The development of corneal and anterior segment optical coherence tomography (OCT) technology has advanced rapidly in recently years. The scan geometry and imaging wavelength are both important choices to make in designing anterior segment OCT systems. Rectangular scan geometry offers the least image distortion and is now used in most anterior OCT systems. The wavelength of OCT light source affects resolution and penetration. An optimal choice of the OCT imaging wavelength (840, 1,050, or 1,310 nm) depends on the application of interest. Newer generation Fourier-domain OCT technology can provide scan speed 100-1000 times faster than the time-domain technology. Various commercial anterior OCT systems are available on the market. A wide spectrum of diagnostic and surgical applications using anterior segment OCT had been investigated, including mapping of corneal and epithelial thicknesses, keratoconus screening, measuring corneal refractive power, corneal surgery planning and evaluation in LASIK, intracorneal ring implantation, assessment of angle closure glaucoma, anterior chamber biometry and intraocular lens implants, intraocular lens power calculation, and eye bank donor cornea screening.

  5. Cortical visual impairment: Characteristics and treatment

    OpenAIRE

    Vučinić, Vesna; Anđelković, Marija; Jablan, Branka; Žigić, Vesna

    2014-01-01

    According to the latest studies, Cortical visual impairment – CVI is one of the most common causes of problems and difficulties in visual functioning. It results from the impairment of the central part of visual system, i.e. visual cortex, posterior visual pathway, or both. The diagnosis is usually made in the first three years of life. The aim of this paper is to present the characteristics of children with CVI, and the strategies used for treatment. CVI has a negative impact on almost all d...

  6. Anterior Uveitis Caused by Ocular Side Effects of Afatinib: A Case Report.

    Science.gov (United States)

    Todokoro, Daisuke; Itakura, Hirotaka; Ibe, Takashi; Kishi, Shoji

    2016-01-01

    Afatinib is a second-generation epidermal growth factor receptor (EGFR) inhibitor that has been shown to be effective against EGFR-mutated non-small cell lung cancer (NSCLC) resistant to conventional EGFR inhibitors such as gefitinib and erlotinib. Although ocular side effects of gefitinib and erlotinib have been reported, those for afatinib have yet to be definitively established. This report presents details on the first case of unilateral iridocyclitis associated with the side effects of afatinib therapy. A 75-year-old Japanese male ex-smoker with EGFR-mutated NSCLC underwent afatinib therapy for multiple metastases. At 2 weeks, bilateral conjunctivitis developed. Topical medication and a 1-week afatinib washout period resulted in the improvement of the conjunctivitis. However, 3 days after the resumption of afatinib, the patient developed unilateral granulomatous anterior uveitis in his right eye. Best-corrected visual acuity (BCVA) measurement indicated a decimal visual acuity of 0.2, while the slit-lamp findings were characterized by granulomatous inflammation, keratic precipitates, Koeppe nodules and posterior synechiae. There was no evidence suggesting other intraocular inflammatory disease or metastatic tumor. The left eye was intact. The use of topical medication including steroids and a washout of afatinib resulted in a gradual subsiding of the anterior uveitis. After resolution of the anterior uveitis, oral afatinib was resumed. BCVA of the right eye finally recovered to a decimal acuity of 1.0. Ophthalmologists should be aware of the possibility that side effects associated with afatinib could cause granulomatous anterior uveitis.

  7. The Anterior Prefrontal Cortex and the Hippocampus Are Negatively Correlated during False Memories

    Directory of Open Access Journals (Sweden)

    Brittany M. Jeye

    2017-01-01

    Full Text Available False memories commonly activate the anterior/dorsolateral prefrontal cortex (A/DLPFC and the hippocampus. These regions are assumed to work in concert during false memories, which would predict a positive correlation between the magnitudes of activity in these regions across participants. However, the A/DLPFC may also inhibit the hippocampus, which would predict a negative correlation between the magnitudes of activity in these regions. In the present functional magnetic resonance imaging (fMRI study, during encoding, participants viewed abstract shapes in the left or right visual field. During retrieval, participants classified each old shape as previously in the “left” or “right” visual field followed by an “unsure”–“sure”–“very sure” confidence rating. The contrast of left-hits and left-misses produced two activations in the hippocampus and three activations in the left A/DLPFC. For each participant, activity associated with false memories (right–“left”–“very sure” responses from the two hippocampal regions was plotted as a function of activity in each A/DLPFC region. Across participants, for one region in the left anterior prefrontal cortex, there was a negative correlation between the magnitudes of activity in this region and the hippocampus. This suggests that the anterior prefrontal cortex might inhibit the hippocampus during false memories and that participants engage either the anterior prefrontal cortex or the hippocampus during false memories.

  8. The Anesthetic Effect of Anterior Middle Superior Alveolar Technique (AMSA)

    Science.gov (United States)

    de Souza Tolentino, Lívia; Barbisan Souza, André; Girardi, Ana Alice; Romito, Giuseppe Alexandre; Araújo, Maurício Guimarães

    2015-01-01

    Anesthesia of the soft and hard tissues of the maxilla may require up to 5 injections. Thus, the aim of this study was to evaluate the anesthetic efficacy of the anterior middle superior alveolar (AMSA) and supraperiosteal injection techniques during subgingival scaling and root planing (SRP). Thirty individuals with periodontitis were scheduled for SRP on the buccal aspect of teeth in the anterior maxilla. Before SRP, on a randomly chosen side of the maxilla, the supraperiosteal injection was performed in 1 session, while the AMSA injection was conducted in the contralateral side of the same patient in another session. Immediately after each SRP session, patients rated their pain perception during the procedure with a visual analog scale. No statistically significant differences in mean pain ratings during SRP were found after both anesthetic techniques (P > .05). This preliminary study demonstrated that the AMSA and supraperiosteal injection techniques provided similar anesthetic comfort during SRP. The AMSA injection could be an alternative to anesthetize the buccal aspect of maxilla, without the undesirable effects on facial structures such as the upper lip, nostrils, and lower eyelids. However, further randomized clinical trials with larger samples are necessary to confirm such results. PMID:26650493

  9. Visual Impairment

    Science.gov (United States)

    ... What Causes Visual Impairment? People rarely lose their eyesight during their teen years. When they do, it's ... inflammation in the eye. It's often found in poor rural countries that have overcrowded living conditions and ...

  10. Acquired anterior staphyloma after corneal ulcer associated with the use of crack

    Directory of Open Access Journals (Sweden)

    Stefânia Barbosa Diniz de Vasconcelos

    Full Text Available ABSTRACT We describe an unusual case of acquired anterior staphyloma in a patient addicted to crack cocaine. At the beginning of his crack cocaine abuse, he noticed redness and irritation of his eyes. Over the next 4 months, the patient also noticed the onset of decreasing visual acuity in his right eye (OD. Initially, his visual acuity was light perception in OD, and slit-lamp examination revealed a corneal infiltrate with a peripheral perforation and an iris prolapse. The patient was hospitalized to ensure compliance with the prescribed treatment and was advised to undergo therapeutic keratoplasty; however, the patient left the hospital against medical advice and was lost to follow-up for the next 6 months. He returned with complaints of photophobia and the inability to close his right eyelids. At this time, his cornea had developed an anterior staphyloma and required a sclerokeratoplasty. Following surgery, the patient was again lost to follow-up.

  11. Visual fields of four batoid fishes: a comparative study.

    Science.gov (United States)

    McComb, D Michelle; Kajiura, Stephen M

    2008-02-01

    The visual fields of elasmobranch fishes are not well characterized even though this is a fundamental element of the visual system. The batoid fishes (skates, rays) form a monophyletic clade within the subclass Elasmobranchii and exhibit a broad range of morphologies and corresponding ecologies. We hypothesized that their visual field characteristics would reflect their diverse morphology and ecology. This was tested by quantifying the monocular, binocular and cyclopean horizontal and vertical visual fields of four batoid species (Raja eglanteria, Urobatis jamaicensis, Dasyatis sabina and Rhinoptera bonasus) that encompassed a range from a basal skate to a more derived ray. The horizontal and vertical visual fields differed significantly among species; however, all species possessed horizontal anterior and dorsal binocular overlaps. Urobatis jamaicensis, a small reef-associated stingray, demonstrated a 360 degrees panoramic visual field in the horizontal plane, and R. bonasus, a schooling benthopelagic ray, a 360 degrees panoramic view in the vertical plane. Large anterior binocular overlaps were measured in D. sabina (72 degrees ) and R. bonasus (46 degrees ) but came at the expense of large posterior blind areas. The anterior binocular overlaps in R. eglanteria (28 degrees ) and U. jamaicensis (34 degrees ) were smaller but were coupled with large monocular fields that provided expansive peripheral views. The most phylogenetically basal species, the clearnose skate (Raja eglanteria), had the most reduced visual field in contrast to the more derived ray species. To our knowledge, this study represents the first comparative assessment of visual fields in basal vertebrates.

  12. Visual cognition

    Energy Technology Data Exchange (ETDEWEB)

    Pinker, S.

    1985-01-01

    This book consists of essays covering issues in visual cognition presenting experimental techniques from cognitive psychology, methods of modeling cognitive processes on computers from artificial intelligence, and methods of studying brain organization from neuropsychology. Topics considered include: parts of recognition; visual routines; upward direction; mental rotation, and discrimination of left and right turns in maps; individual differences in mental imagery, computational analysis and the neurological basis of mental imagery: componental analysis.

  13. Electrostimulation mapping of comprehension of auditory and visual words.

    Science.gov (United States)

    Roux, Franck-Emmanuel; Miskin, Krasimir; Durand, Jean-Baptiste; Sacko, Oumar; Réhault, Emilie; Tanova, Rositsa; Démonet, Jean-François

    2015-10-01

    In order to spare functional areas during the removal of brain tumours, electrical stimulation mapping was used in 90 patients (77 in the left hemisphere and 13 in the right; 2754 cortical sites tested). Language functions were studied with a special focus on comprehension of auditory and visual words and the semantic system. In addition to naming, patients were asked to perform pointing tasks from auditory and visual stimuli (using sets of 4 different images controlled for familiarity), and also auditory object (sound recognition) and Token test tasks. Ninety-two auditory comprehension interference sites were observed. We found that the process of auditory comprehension involved a few, fine-grained, sub-centimetre cortical territories. Early stages of speech comprehension seem to relate to two posterior regions in the left superior temporal gyrus. Downstream lexical-semantic speech processing and sound analysis involved 2 pathways, along the anterior part of the left superior temporal gyrus, and posteriorly around the supramarginal and middle temporal gyri. Electrostimulation experimentally dissociated perceptual consciousness attached to speech comprehension. The initial word discrimination process can be considered as an "automatic" stage, the attention feedback not being impaired by stimulation as would be the case at the lexical-semantic stage. Multimodal organization of the superior temporal gyrus was also detected since some neurones could be involved in comprehension of visual material and naming. These findings demonstrate a fine graded, sub-centimetre, cortical representation of speech comprehension processing mainly in the left superior temporal gyrus and are in line with those described in dual stream models of language comprehension processing.

  14. Severe anterior uveitis associated with idiopathic dacryoadenitis in diabetes mellitus patient

    Directory of Open Access Journals (Sweden)

    Takahashi YY

    2011-05-01

    Full Text Available Yasuhiro Takahashi¹, Hirohiko Kakizaki¹, Akihiro Ichinose², Masayoshi Iwaki¹¹Department of Ophthalmology, Aichi Medical University, Nagakute, Aichi, Japan; ²Department of Plastic Surgery, Kobe University, Kobe, Hyogo, JapanAbstract: A 38-year-old woman with diabetes mellitus complained of acute visual loss in the left eye (20/200 and swollen left upper eyelid. Slit lamp examination of the left eye revealed ciliary injection, posterior synechia iritis, numerous inflammatory cells, and fibrin exudates in the anterior chamber. T1-weighted enhanced magnetic resonance imaging demonstrated left lacrimal gland enhancement with inflammatory spread to the left anterior ocular segment. Blood examination showed increased blood sugar but the other components were within normal limits. The patient was treated with steroid pulse therapy (methylprednisolone 1 g/day × 3 days under a blood sugar control regimen in consultation with an endocrinologist, after which additional peribulbar injection of triamcinolone acetonide (40 mg was performed. Resolution of the anterior uveitis and the dacryoadenitis was obtained after 2 months and there was no recurrence 1 year after the therapy. This is a rare case of severe anterior uveitis caused by idiopathic dacryoadenitis in a patient with diabetes mellitus.Keywords: anterior uveitis, idiopathic dacryoadenitis, diabetes mellitus, magnetic resonance imaging, steroid

  15. Fluoroscopically-Guided Posterior Approach for Shoulder Magnetic Resonance Arthrography: Comparison with Conventional Anterior Approach

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Koun J.; Ha, Doo Hoe; Lee, Sang Min [Dept. of Radiology, CHA Budang Medical Center, CHA University College of Medicine, Seongnam (Korea, Republic of)

    2011-10-15

    To prospectively evaluate the usefulness of the fluoroscopically-guided posterior approach compared with the anterior approach for shoulder magnetic resonance(MR) arthrography. Institutional review board approval and informed consent were obtained. Among 60 shoulder MR arthrographies performed on 59 patients with symptomatic shoulders, an intra-articular injection was performed (30 cases using the anterior approach and 30 using the posterior approach). Procedure-related pain was assessed by using a 5 score visual analogue scale (VAS). Depth of the puncture and standardized depth of puncture by body mass index (BMI) were recorded. The contrast leakage along the course of the puncture was evaluated by reviewing the MR. The statistical analyses included the Mann-Whitney U and Kruskal-Wallis test. There was no significant difference in VAS scores between the anterior and posterior groups (1.77 {+-} 1.10 vs. 1.80 {+-} 0.96). Depth of puncture and standardized depth of puncture by BMI were significantly shorter in the posterior group than those in the anterior group (4.4 {+-} 0.8 cm and 1.8 {+-} 0.3 cm vs. 6.6 {+-} 0.9 cm and 2.8 {+-} 0.4 cm, p < 0.001), respectively. The incidence of contrast leakage was more frequent in the posterior group (p = 0.003). The posterior approach will be useful in shoulder MR arthrography with a suspected anterior pathology, a postoperative follow-up study or obese patient.

  16. Magnetic resonance imaging of luxury perfusion of the optic nerve head in anterior ischemic optic neuropathy.

    Science.gov (United States)

    Yovel, Oren S; Katz, Miriam; Leiba, Hana

    2012-09-01

    A 49-year-old woman with painless reduction in visual acuity in her left eye was found to have nonarteritic anterior ischemic optic neuropathy (NAION). Fluorescein angiography revealed optic disc capillary leakage consistent with "luxury perfusion." Contrast-enhanced FLAIR magnetic resonance imaging (MRI) showed marked enhancement of the left optic disc. Resolution of the optic disc edema and the MRI abnormalities followed a similar time course. This report appears unique in documenting the MRI findings of luxury perfusion in NAION.

  17. A visual thalamocortical slice.

    Science.gov (United States)

    MacLean, Jason N; Fenstermaker, Vivian; Watson, Brendon O; Yuste, Rafael

    2006-02-01

    We describe a thalamocortical slice preparation in which connectivity between the mouse lateral geniculate nucleus (LGN) and primary visual cortex (V1) is preserved. Through DiI injections in fixed brains we traced and created a three-dimensional model of the mouse visual pathways. From this computer model we designed a slice preparation that contains a projection from LGN to V1. We prepared brain slices with these predicted coordinates and demonstrated anatomical LGN-V1 connectivity in these slices after LGN tracer injections. We also revealed functional LGN-V1 connectivity by stimulating LGN electrically and detecting responses in layer 4 of V1 using calcium imaging, field potential recordings and whole-cell recordings. We also identified layer-4 neurons that receive direct thalamocortical input. Finally, we compared cortical activity after LGN stimulation with spontaneous cortical activity and found significant overlap of the spatiotemporal dynamics generated by both types of events.

  18. Chordal geometry determines the shape and extent of systolic anterior mitral motion: in vitro studies.

    Science.gov (United States)

    Cape, E G; Simons, D; Jimoh, A; Weyman, A E; Yoganathan, A P; Levine, R A

    1989-05-01

    In patients with hypertrophic cardiomyopathy, the mitral valve moves anteriorly and assumes a unique shape, with mitral-septal contact centrally and preserved valve orifice area laterally. This shape is not clearly predicted by the Venturi mechanism, which stresses flow above the valve as opposed to changes intrinsic to the valve. On the other hand, it has been suggested that displacement of the papillary muscles anteriorly and toward one another, as observed in this disease, can promote anterior mitral valve motion and produce this unusual shape. The purpose of this in vitro study was to test the hypotheses that anterior motion of a membrane in a flow field can be generated by altering the distribution or effectiveness of chordal tension tethering the membrane, and that the shape achieved by this membrane depends on the geometry of chordal tension. Accordingly, a horizontal leaflet mounted in a flow chamber was attached by chords at its distal end to a series of upstream screws. Chordal tension could be varied by turning the screws or redirected by shifting the screws anteriorly. Anterior leaflet motion having the same unusual configuration seen in patients was reproduced by decreasing central chordal restraint while tension on the leaflet edges was maintained. Directing chordal tension anteriorly caused greater degrees of anterior motion at earlier stages in the release of chordal restraint; increased flow rate had a similar but less marked effect. These studies suggest that primary geometric alterations in the papillary-mitral apparatus can play an important role in determining the presence and geometry of systolic anterior mitral motion. The nature of these alterations suggests a role for anterior and inward papillary muscle displacement in promoting such motion. The geometric factors embodied in this model can explain many observed features of this motion not adequately explained by the Venturi effect, such as early systolic onset and the importance of a

  19. Visual comparison for information visualization

    KAUST Repository

    Gleicher, M.

    2011-09-07

    Data analysis often involves the comparison of complex objects. With the ever increasing amounts and complexity of data, the demand for systems to help with these comparisons is also growing. Increasingly, information visualization tools support such comparisons explicitly, beyond simply allowing a viewer to examine each object individually. In this paper, we argue that the design of information visualizations of complex objects can, and should, be studied in general, that is independently of what those objects are. As a first step in developing this general understanding of comparison, we propose a general taxonomy of visual designs for comparison that groups designs into three basic categories, which can be combined. To clarify the taxonomy and validate its completeness, we provide a survey of work in information visualization related to comparison. Although we find a great diversity of systems and approaches, we see that all designs are assembled from the building blocks of juxtaposition, superposition and explicit encodings. This initial exploration shows the power of our model, and suggests future challenges in developing a general understanding of comparative visualization and facilitating the development of more comparative visualization tools. © The Author(s) 2011.

  20. Coracoid syndrome: a neglected cause of anterior shoulder pain

    Science.gov (United States)

    GIGANTE, ANTONIO; BOTTEGONI, CARLO; BARBADORO, PAMELA

    2016-01-01

    Purpose the present prospective open-label study was designed to gain further insights into a condition thought to constitute a neglected but not uncommon syndrome characterized by anterior shoulder pain and tenderness to palpation over the apex of the coracoid process, not related to rotator cuff or pectoralis minor tendinopathy, long head of the biceps tendon disorders, or instability. The aim was to clarify its prevalence, clinical characteristics, differential diagnosis and response to corticosteroid injections. Methods patients with primary anterior shoulder pain precisely reproduced by deep pressure on the apex of the coracoid process were recruited. Patients with clinical or instrumental signs of other shoulder disorders were excluded. Patients were given an injection of triamcinolone acetonide 40 mg/ml 1 ml at the coracoid trigger point. They were evaluated after 15, 30 and 60 days and at 2 years using Equal Visual Analog Scale (EQ-VAS) and the Italian version of the Simple Shoulder Test (SST). Results between January 1 and December 31 2010, we treated 15 patients aged 26–66 years. The majority were women (86.67%). At 15 days, 6 (40%) patients reported complete resolution of their symptoms, while 9 (60%) complained of residual symptoms and received another injection. At 30 days, 14 (93.33%) patients were pain-free and very satisfied. At 2 years, the 14 patients who had been asymptomatic at 30 days reported that they had experienced no further pain or impaired shoulder function. The analysis of variance for repeated measures showed a significant effect of time on EQ-VAS and SST scores. Conclusions the present study documents the existence, and characteristics, of a “coracoid syndrome” characterized by anterior shoulder pain and tenderness to palpation over the apex of the coracoid process and showed that the pain is usually amenable to steroid treatment. This syndrome should be clearly distinguished from anterior shoulder pain due to other causes, in

  1. Visual Education

    DEFF Research Database (Denmark)

    Buhl, Mie; Flensborg, Ingelise

    2010-01-01

    The intrinsic breadth of various types of images creates new possibilities and challenges for visual education. The digital media have moved the boundaries between images and other kinds of modalities (e.g. writing, speech and sound) and have augmented the possibilities for integrating the functi......The intrinsic breadth of various types of images creates new possibilities and challenges for visual education. The digital media have moved the boundaries between images and other kinds of modalities (e.g. writing, speech and sound) and have augmented the possibilities for integrating...... the functions of the images and visuality in new forms of knowledge-building beyond traditional boundaries of school subjects. New learning cultures emerge and place the visual skills of decoding and meaning-making in the centre of future competences for citizens in a globalised world.   This paper discusses...... the learning potential of images and visuality from two perspectives: 1) The perspective of digital media which are assumed to form an increasing part of experience and communication from the use of internet, tv and mobile devices. 2) The perspective of culture where images and visualisations are assumed...

  2. The Anterior Thalamus Provides A Subcortical Circuit Supporting Memory And Spatial Navigation

    Directory of Open Access Journals (Sweden)

    Shane M O‘Mara

    2013-08-01

    Full Text Available The anterior thalamic nuclei, a central component of Papez’ circuit, are generally assumed to be key constituents of the neural circuits responsible for certain categories of learning and memory. Supporting evidence for this contention is that damage to either of two brain regions, the medial temporal lobe and the medial diencephalon, is most consistently associated with anterograde amnesia. Within these respective regions, the hippocampal formation and the anterior thalamic nuclei (anteromedial, anteroventral, anterodorsal are the particular structures of interest. The extensive direct and indirect hippocampal-anterior thalamic interconnections and the presence of theta-modulated cells in both sites further support the hypothesis that these structures constitute a neuronal network crucial for memory and cognition. The major tool in understanding how the brain processes information is the analysis of neuronal output at each hierarchical level along the pathway of signal propagation coupled with neuroanatomical studies. Here, we discuss the electrophysiological properties of cells in the anterior thalamic nuclei with an emphasis on their role in spatial navigation. In addition, we describe neuroanatomical and functional relationships between the anterior thalamic nuclei and hippocampal formation.

  3. [Surgical anatomy of the anterior mediastinum].

    Science.gov (United States)

    Biondi, Alberto; Rausei, Stefano; Cananzi, Ferdinando C M; Zoccali, Marco; D'Ugo, Stefano; Persiani, Roberto

    2007-01-01

    The mediastinum is located from the thoracic inlet to the diaphragm between the left and right pleural cavities and contains vital structures of the circulatory, respiratory, digestive, and nervous system. Over the years, since there are no fascial or anatomic planes, anatomists and radiologists have suggested various schemes for subdividing the mediastinum and several anatomical and radiological classifications of the mediastinum are reported in the literature. The most popular of these scheme divides medistinum, for purposes of description, into two parts: an upper portion, above the upper level of the pericardium, which is named the superior mediastinum; and a lower portion, below the upper level of the pericardium. For clinical purposes, the mediastinum may be subdivided into three major areas, i.e. anterior, middle, and posterior compartments. The anterior mediastinum is defined as the region posterior to the sternum and anterior to the heart and brachiocephalic vessels. It extends from the thoracic inlet to the diaphragm and contains the thymus gland, fat, and lymph nodes. This article will review surgical anatomy of the anterior mediastinum and will focus on the surgical approch to anterior mediastinum and thymic diseases.

  4. Visualizing Transformation

    DEFF Research Database (Denmark)

    Pedersen, Pia

    2012-01-01

    Transformation, defined as the step of extracting, arranging and simplifying data into visual form (M. Neurath, 1974), was developed in connection with ISOTYPE (International System Of TYpographic Picture Education) and might well be the most important legacy of Isotype to the field of graphic...... design. Recently transformation has attracted renewed interest because of the book ‘The Transformer’ written by Robin Kinross and Marie Neurath. My on-going research project, summarized in this paper, identifies and depicts the essential principles of data visualization underlying the process...... of transformation with reference to Marie Neurath’s sketches on the Bilston Project. The material has been collected at the Otto and Marie Neurath Collection housed at the University of Reading, UK. By using data visualization as a research method to look directly into the process of transformation the project...

  5. Visual cognition

    Energy Technology Data Exchange (ETDEWEB)

    Pinker, S.

    1985-01-01

    This collection of research papers on visual cognition first appeared as a special issue of Cognition: International Journal of Cognitive Science. The study of visual cognition has seen enormous progress in the past decade, bringing important advances in our understanding of shape perception, visual imagery, and mental maps. Many of these discoveries are the result of converging investigations in different areas, such as cognitive and perceptual psychology, artificial intelligence, and neuropsychology. This volume is intended to highlight a sample of work at the cutting edge of this research area for the benefit of students and researchers in a variety of disciplines. The tutorial introduction that begins the volume is designed to help the nonspecialist reader bridge the gap between the contemporary research reported here and earlier textbook introductions or literature reviews.

  6. THYMOLIPOMA: A RARE, LARGE ANTERIOR MEDIASTINAL MASS

    Directory of Open Access Journals (Sweden)

    Premananth

    2015-07-01

    Full Text Available Thymolipoma is a rare benign tumor of anterior mediastinum, described by Lange in 1916. 1 Less than 200 cases have been reported worldwide. 2 It accounts for 2% to 9% of thymic tumours. 3 We report a case of thymolipoma in a 37 year s old male patient, who pre sented with cough, dys p nea, chest pain for 2 months. CT THORAX revealed a large anterior mediastinal mass extending in to right hemithorax arising from thymus gland, with multiple areas of fat density, no significant mediastinal adenopathy, complete collap se of right middle and lower lobe suggestive of thymolipoma. CT guided biopsy suggestive of thymic neoplasm. The tumour was removed enbloc through surgery. Histopathological examination of large mass lesion confirmed thymolipoma. We report this case to emp hasize the importance of considering thymolipoma as a differential diagnosis of anterior mediastinal mass, although rare.

  7. Esthetic crown lengthening for maxillary anterior teeth.

    Science.gov (United States)

    Sonick, M

    1997-08-01

    In the maxillary anterior region, the gingival labial margin position is an important parameter in the achievement of an ideal smile. The relationship between the periodontium and the restoration is critical if gingival health and esthetics are to be achieved. Periodontal therapy is a necessary and useful adjunct when any anterior restoration is undertaken. Anterior surgical crown lengthening may be undertaken to avoid restorative margin impingement on the biologic width. Crown lengthening is also used to alter the gingival labial profiles. This article discusses the esthetic parameters of ideal gingival labial positions and presents a classification of crown-lengthening procedures and the procedure for a two-stage crown-lengthening technique. The two-stage crown-lengthening technique is surgically precise because healing is predictable.

  8. Tibialis anterior stretch reflex in early stance is suppressed by repetitive transcranial magnetic stimulation

    DEFF Research Database (Denmark)

    Zuur, Abraham T; Christensen, Mark Schram; Sinkjær, Thomas;

    2009-01-01

    Abstract A rapid plantar flexion perturbation in the early stance phase of walking elicits a large stretch reflex in tibialis anterior (TA). In this study we use repetitive Transcranial Magnetic Stimulation (rTMS) to test if this response is mediated through a transcortical pathway. TA stretch...... reflexes were elicited in the early stance phase of the step cycle during treadmill walking. 20 minutes of 1 Hz rTMS at 115% resting motor threshold (MTr) significantly decreased (p

  9. Anterior ischemic optic neuropathy following dengue fever.

    Science.gov (United States)

    Ramakrishnan, Reshma; Shrivastava, Saurabh; Deshpande, Shrikant; Patkar, Priyanka

    2016-01-01

    Dengue fever is caused by a flavivirus. This infection is endemic in the tropics and warm temperate regions of the world. Ocular manifestations of dengue fever include subconjunctival, vitreous, and retinal haemorrhages; posterior uveitis; optic neuritis; and maculopathies, haemorrhage, and oedema. However anterior ischemic optic neuropathy is a rare presentation. Optic nerve ischemia most frequently occurs at the optic nerve head, where structural crowding of nerve fibers and reduction of the vascular supply may combine to impair perfusion to a critical degree and produce optic disc oedema. Here we present a case of anterior ischemic optic neurapathy associated with dengue fever.

  10. Study of aqueous humour in anterior uveitis

    Directory of Open Access Journals (Sweden)

    Kalsy Jairaj

    1990-01-01

    Full Text Available Aetiological diagnosis of anterior uveitis was made clinically and substantiated with relevant investigations. Aqueous humour obtained under aseptic conditions, was analyzed for the cells study, culture and protein profile, using polyacrylamide gel electrophoresis. The results were analysed with the help of known clinical facts. Culture and smears were invariably negative, while the lymphocytes were present in varying numbers, polymorphs and macrophages afforded a useful clue for confirmatory diagnosis. The electrophoretic pattern of the proteins was related to the duration of the disease and was same in a group while it was distinctive among different groups of anterior uveitis.

  11. ANTERIOR OSTEOPHYTE IDENTIFICATION IN CERVICAL VERTEBRAE

    Directory of Open Access Journals (Sweden)

    A. T. Chougale

    2011-06-01

    Full Text Available Radiologist always examines X-ray to determine abnormal changes in cervical, lumbar & thoracic vertebrae. Osteophyte (bony growth may appear at the corners of vertebrae so that vertebral shape becomes abnormal. This paper presents the idea from Image processing techniques such as customised Hough transform which will be used for segmentation which should be independent of rotation, scale, noise & shape. This segmented image will be then used for computing size invariant, convex hull based features to differentiate normal cervical vertebrae from cervical vertebrae containing anterior osteophyte. This approach effectively finds anterior osteophytes in cervical vertebrae.

  12. Dual (type IV left anterior descending artery

    Directory of Open Access Journals (Sweden)

    Ozdil Baskan

    2013-11-01

    Full Text Available Congenital coronary artery anomalies are uncommon. Dual left anterior descending coronary artery (LAD is defined as the presence of two LADs within the anterior interventricular sulcus (AIVS, and is classified into four types. Type IV is a rarely reported subtype and differs from the others, with a long LAD originating from the right coronary artery (RCA. Dual LAD is a benign coronary artery anomaly, but should be recognised especially before interventional procedures. With the increasing use of multidedector computed tomography (MDCT, it is essential for radiologists to be aware of this entity and the cross-sectional findings.

  13. Ventral and dorsal streams processing visual motion perception (FDG-PET study

    Directory of Open Access Journals (Sweden)

    Becker-Bense Sandra

    2012-07-01

    Full Text Available Abstract Background Earlier functional imaging studies on visually induced self-motion perception (vection disclosed a bilateral network of activations within primary and secondary visual cortex areas which was combined with signal decreases, i.e., deactivations, in multisensory vestibular cortex areas. This finding led to the concept of a reciprocal inhibitory interaction between the visual and vestibular systems. In order to define areas involved in special aspects of self-motion perception such as intensity and duration of the perceived circular vection (CV or the amount of head tilt, correlation analyses of the regional cerebral glucose metabolism, rCGM (measured by fluorodeoxyglucose positron-emission tomography, FDG-PET and these perceptual covariates were performed in 14 healthy volunteers. For analyses of the visual-vestibular interaction, the CV data were compared to a random dot motion stimulation condition (not inducing vection and a control group at rest (no stimulation at all. Results Group subtraction analyses showed that the visual-vestibular interaction was modified during CV, i.e., the activations within the cerebellar vermis and parieto-occipital areas were enhanced. The correlation analysis between the rCGM and the intensity of visually induced vection, experienced as body tilt, showed a relationship for areas of the multisensory vestibular cortical network (inferior parietal lobule bilaterally, anterior cingulate gyrus, the medial parieto-occipital cortex, the frontal eye fields and the cerebellar vermis. The “earlier” multisensory vestibular areas like the parieto-insular vestibular cortex and the superior temporal gyrus did not appear in the latter analysis. The duration of perceived vection after stimulus stop was positively correlated with rCGM in medial temporal lobe areas bilaterally, which included the (para-hippocampus, known to be involved in various aspects of memory processing. The amount of head tilt was found

  14. Dorsal anterior cingulate cortex in typically developing children: Laterality analysis

    Directory of Open Access Journals (Sweden)

    Jue Wang

    2015-10-01

    Full Text Available We aimed to elucidate the dACC laterality in typically developing children and their sex/age-related differences with a sample of 84 right-handed children (6–16 years, 42 boys. We first replicated the previous finding observed in adults that gray matter density asymmetry in the dACC was region-specific: leftward (left > right in its superior part, rightward (left < right in its inferior part. Intrinsic connectivity analysis of these regions further revealed region-specific asymmetric connectivity profiles in dACC as well as their sex and age differences. Specifically, the superior dACC connectivity with frontoparietal network and the inferior dACC connectivity with visual network are rightward. The superior dACC connectivity with the default network (lateral temporal cortex was more involved in the left hemisphere. In contrast, the inferior dACC connectivity with the default network (anterior medial prefrontal cortex was more lateralized towards the right hemisphere. The superior dACC connectivity with lateral visual cortex was more distinct across two hemispheres in girls than that in boys. This connection in boys changed with age from right-prominent to left-prominent asymmetry whereas girls developed the connection from left-prominent to no asymmetry. These findings not only highlight the complexity and laterality of the dACC but also provided insights into dynamical structure–function relationships during the development.

  15. Oral vitamins C and E as additional treatment in patients with acute anterior uveitis: a randomised double masked study in 145 patients

    OpenAIRE

    van Rooij, Jeroen; Schwartzenberg, S.G.; Baarsma, Seerp; Mulder, Paul

    1999-01-01

    textabstractAIM: To investigate the effect of additional oral vitamins C and E on acute anterior uveitis. METHODS: A placebo controlled double masked study on the effect of vitamin C 500 mg in combination with vitamin E 100 mg twice daily in 145 patients with acute anterior uveitis. As a primary end point variable, laser cell/flare measurements were performed. Best corrected and stenopeic visual acuity (VA) testing and clinical variable scores were measured. RESULTS: Laser flare measurements ...

  16. Visualizing inequality

    Science.gov (United States)

    Eliazar, Iddo

    2016-07-01

    The study of socioeconomic inequality is of substantial importance, scientific and general alike. The graphic visualization of inequality is commonly conveyed by Lorenz curves. While Lorenz curves are a highly effective statistical tool for quantifying the distribution of wealth in human societies, they are less effective a tool for the visual depiction of socioeconomic inequality. This paper introduces an alternative to Lorenz curves-the hill curves. On the one hand, the hill curves are a potent scientific tool: they provide detailed scans of the rich-poor gaps in human societies under consideration, and are capable of accommodating infinitely many degrees of freedom. On the other hand, the hill curves are a powerful infographic tool: they visualize inequality in a most vivid and tangible way, with no quantitative skills that are required in order to grasp the visualization. The application of hill curves extends far beyond socioeconomic inequality. Indeed, the hill curves are highly effective 'hyperspectral' measures of statistical variability that are applicable in the context of size distributions at large. This paper establishes the notion of hill curves, analyzes them, and describes their application in the context of general size distributions.

  17. Ceratoconjuntivite alérgica e complicações no segmento ocular anterior de pacientes Evaluation of anterior ocular segment complications in patients with allergic keratoconjunctivitis

    Directory of Open Access Journals (Sweden)

    Patrícia Bezerra de Menezes Botelho

    2003-01-01

    Full Text Available INTRODUÇÃO: A alergia ocular é condição que pode ocasionar sintomas de coceira, ardor e lacrimejamento, podendo também ser ameaçadora para visão. A fisiopatologia envolve mecanismos de hipersensibilidade imunológica. Devido a fatores imunológicos, o segmento anterior destes pacientes está mais suscetível a alterações que ameaçam a acuidade visual, tais como: opacidades corneanas, ceratocone e catarata. MÉTODOS: Foram revistos, retrospectivamente, 186 pacientes com ceratoconjuntivite alérgica e selecionados pacientes que possuíam alterações de segmento anterior e acuidade visual menor ou igual a 0,6 corrigida em um ou ambos os olhos. A AV 0,6 foi escolhida aleatoriamente a fim de agrupar os pacientes. Estes pacientes foram analisados quanto à idade, sexo, tipo de alergia, tempo de aparecimento da doença (considerado como tempo de aparecimento de sintomas, tempo de latência (tempo que surgiu a complicação após o primeiro dia de atendimento, alterações sistêmicas, efeitos colaterais das drogas e complicações oculares. Estes pacientes não poderiam melhorar a AV com tratamento tópico e tinham acompanhamento mínimo de 3 meses. RESULTADOS: As alterações de segmento anterior que causaram AV menor ou igual a 0,6 (refração ou estenopeico sem possibilidade de melhora com medicação tópica foram: úlcera em escudo: 5 casos, catarata: 3 casos, opacidade corneana: 6 casos, perfuração ocular: 2 casos e ceratocone: 13 casos. CONCLUSÃO: Pacientes com ceratoconjuntivite alérgica podem ter como principais causas de baixa acuidade visual alterações de segmento anterior, entre elas, opacidades corneanas, ceratocone e catarata.PURPOSE: To evaluate complications of allergic keratoconjuctivitis that caused reduction in visual acuity to 0.6 or less and that could not solve with clinic treatment. METHODS: We analyzed retrospectively 186 charts and selected patients with visual acuity less than 0.6 on Snellen chart, associated

  18. Anterior herniation of lumbar disc induces persistent visceral pain:discogenic visceral pain

    Institute of Scientific and Technical Information of China (English)

    TANG Yuan-zhang; Moore-Langston Shannon; LAI Guang-hui; LI Xuan-ying; LI Na; NI Jia-xiang

    2013-01-01

    Background Visceral pain is a common cause for seeking medical attention.Afferent fibers innervating viscera project to the central nervous system via sympathetic nerves.The lumbar sympathetic nerve trunk lies in front of the lumbar spine.Thus,it is possible for patients to suffer visceral pain originating from sympathetic nerve irritation induced by anterior herniation of the lumbar disc.This study aimed to evaluate lumbar discogenic visceral pain and its treatment.Methods Twelve consecutive patients with a median age of 56.4 years were enrolled for investigation between June 2012 and December 2012.These patients suffered from long-term abdominal pain unresponsive to current treatment options.Apart from obvious anterior herniation of the lumbar discs and high signal intensity anterior to the herniated disc on magnetic resonance imaging,no significant pathology was noted on gastroscopy,vascular ultrasound,or abdominal computed tomography (CT).To prove that their visceral pain originated from the anteriorly protruding disc,we evaluated whether pain was relieved by sympathetic block at the level of the anteriorly protruding disc.If the block was effective,CT-guided continuous lumbar sympathetic nerve block was finally performed.Results All patients were positive for pain relief by sympathetic block.Furthermore,the average Visual Analog Scale of visceral pain significantly improved after treatment in all patients (P <0.05).Up to 11/12 patients had satisfactory pain relief at 1 week after discharge,8/12 at 4 weeks,7/12 at 8 weeks,6/12 at 12 weeks,and 5/12 at 24 weeks.Conclusions It is important to consider the possibility of discogenic visceral pain secondary to anterior herniation of the lumbar disc when forming a differential diagnosis for seemingly idiopathic abdominal pain.Continuous lumbar sympathetic nerve block is an effective and safe therapy for patients with discogenic visceral pain.

  19. Anterior Chamber Live Loa loa: Case Report.

    Science.gov (United States)

    Kagmeni, G; Cheuteu, R; Bilong, Y; Wiedemann, P

    2016-01-01

    We reported a case of unusual intraocular Loa loa in a 27-year-old patient who presented with painful red eye. Biomicroscopy revealed a living and active adult worm in the anterior chamber of the right eye. After surgical extraction under local anesthesia, parasitological identification confirmed L. loa filariasis.

  20. Causes of anterior cruciate ligament injuries

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    Ristić Vladimir

    2010-01-01

    Full Text Available In order to prevent anterior cruciate ligament injuries it is necessary to define risk factors and to analyze the most frequent causes of injuries - that being the aim of this study. The study sample consisted of 451 surgically treated patients, including 400 sportsmen (65% of them being active and 35% recreational sportsmen, 29% female and 71% male; of whom 90% were younger than 35. Sports injuries, as the most frequent cause of anterior cruciate ligament injuries, were recorded in 88% of patients (non-contact ones in 78% and contact ones in 22%, injuries occurring in everyday activities in 11% and in traffic in 1%. Among sportsmen, reconstruction of the anterior cruciate ligament was most frequently performed in football players (48%, then in handball players (22%, basketball players (13%, volleyball players (8%, martial arts fighters (4%. However, the injury incidence was the highest among the active basketball players (1 injured among 91 active players. Type of footwear, warming up before the activity, genetic predisposition and everyday therapy did not have a significant influence on getting injured. Anterior cruciate ligament injuries happened three times more often during matches, in the middle and at the end of a match and training session (79%, at landing after the jump or when changing direction of movement (75% without a contact with other competitors, on dry surfaces (79%, among not so well prepared sportsmen.

  1. ANTERIOR COLUMN FRACTURES OF THE ACETABULUM

    NARCIS (Netherlands)

    HEEG, M; OTTER, N; KLASEN, HJ

    1992-01-01

    We retrospectively reviewed 20 patients at three to 19 years after displaced anterior fracture-dislocations of the hip. Eighteen of them were treated by traction, after ensuring that the femoral head was adequately reduced beneath the undisrupted part of the weight-bearing dome. Two required operati

  2. Balanitis xerotica obliterans involving anterior urethra.

    Science.gov (United States)

    Herschorn, S; Colapinto, V

    1979-12-01

    Balanitis xerotica obliterans (BXO) is known to affect the urethral meatus, glans, and prepuce. We describe a case of biopsy-proved BXO that involves not only the usual areas but the anterior urethra as well. Of added interest is the subsequent development of squamous cell carcinoma in the fossa navicularis. The literature is reviewed.

  3. Treatment for acute anterior cruciate ligament tear

    DEFF Research Database (Denmark)

    Frobell, Richard B; Roos, Harald P; Roos, Ewa M;

    2013-01-01

    To compare, in young active adults with an acute anterior cruciate ligament (ACL) tear, the mid-term (five year) patient reported and radiographic outcomes between those treated with rehabilitation plus early ACL reconstruction and those treated with rehabilitation and optional delayed ACL...

  4. Guideline on anterior cruciate ligament injury

    NARCIS (Netherlands)

    Meuffels, Duncan E; Poldervaart, Michelle T; Diercks, Ronald; Fievez, Alex W F M; Patt, Thomas W; Hart, Cor P van der; Hammacher, Eric R; Meer, Fred van der; Goedhart, Edwin A; Lenssen, Anton F; Muller-Ploeger, Sabrina B; Pols, Margreet A; Saris, Daniel B F

    2012-01-01

    The Dutch Orthopaedic Association has a long tradition of development of practical clinical guidelines. Here we present the recommendations from the multidisciplinary clinical guideline working group for anterior cruciate ligament injury. The following 8 clinical questions were formulated by a steer

  5. Novel Insights into Anterior Cruciate Ligament Injury

    NARCIS (Netherlands)

    D.E. Meuffels (Duncan)

    2011-01-01

    textabstractAnterior cruciate ligament (ACL) injury is one of the most common sports injuries of the knee. ACL reconstruction has become, standard orthopaedic practice worldwide with an estimated 175,000 reconstructions per year in the United States.6 The ACL remains the most frequently studied liga

  6. Treatment for acute anterior cruciate ligament tear

    DEFF Research Database (Denmark)

    Frobell, Richard B; Roos, Harald P; Roos, Ewa M;

    2015-01-01

    STUDY QUESTION: In young active adults with an acute anterior cruciate ligament (ACL) rupture, do patient reported or radiographic outcomes after five years differ between those treated with rehabilitation plus early ACL reconstruction and those treated with rehabilitation and optional delayed ACL...

  7. Making memories: the development of long-term visual knowledge in children with visual agnosia.

    Science.gov (United States)

    Metitieri, Tiziana; Barba, Carmen; Pellacani, Simona; Viggiano, Maria Pia; Guerrini, Renzo

    2013-01-01

    There are few reports about the effects of perinatal acquired brain lesions on the development of visual perception. These studies demonstrate nonseverely impaired visual-spatial abilities and preserved visual memory. Longitudinal data analyzing the effects of compromised perceptions on long-term visual knowledge in agnosics are limited to lesions having occurred in adulthood. The study of children with focal lesions of the visual pathways provides a unique opportunity to assess the development of visual memory when perceptual input is degraded. We assessed visual recognition and visual memory in three children with lesions to the visual cortex having occurred in early infancy. We then explored the time course of visual memory impairment in two of them at 2  years and 3.7  years from the initial assessment. All children exhibited apperceptive visual agnosia and visual memory impairment. We observed a longitudinal improvement of visual memory modulated by the structural properties of objects. Our findings indicate that processing of degraded perceptions from birth results in impoverished memories. The dynamic interaction between perception and memory during development might modulate the long-term construction of visual representations, resulting in less severe impairment.

  8. Making Memories: The Development of Long-Term Visual Knowledge in Children with Visual Agnosia

    Directory of Open Access Journals (Sweden)

    Tiziana Metitieri

    2013-01-01

    Full Text Available There are few reports about the effects of perinatal acquired brain lesions on the development of visual perception. These studies demonstrate nonseverely impaired visual-spatial abilities and preserved visual memory. Longitudinal data analyzing the effects of compromised perceptions on long-term visual knowledge in agnosics are limited to lesions having occurred in adulthood. The study of children with focal lesions of the visual pathways provides a unique opportunity to assess the development of visual memory when perceptual input is degraded. We assessed visual recognition and visual memory in three children with lesions to the visual cortex having occurred in early infancy. We then explored the time course of visual memory impairment in two of them at 2 years and 3.7 years from the initial assessment. All children exhibited apperceptive visual agnosia and visual memory impairment. We observed a longitudinal improvement of visual memory modulated by the structural properties of objects. Our findings indicate that processing of degraded perceptions from birth results in impoverished memories. The dynamic interaction between perception and memory during development might modulate the long-term construction of visual representations, resulting in less severe impairment.

  9. Perawatan Ortodontik Gigi Anterior Berjejal dengan Tulang Alveolar yang Tipis

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    Miesje K. Purwanegara

    2015-09-01

    Full Text Available Anterior teeth movement in orthodontic treatment is limited to labiolingual direction by very thin alveolar bone. An uncontrolled anterior tooth movement to labiolingual direction can cause alveolar bone perforation at its root segment. This case report is to remind us that alveolar bone thickness limits orthodontc tooth movement. A case of crowded anterior teeth with thin alveolar bone in malocclusion I is reported. This case is treated using adgewise orthodontic appliance. Protraction of anterior teeth is anticipated due to thin alveolar bone on the anterior surface. The conclusion is although the alveolar bone surrounding the crowded anterior teeth is thin, by controlling the movement the teeth reposition is allowed.

  10. Do visual illusions probe the visual brain? Illusions in action without a dorsal visual stream.

    Science.gov (United States)

    Coello, Yann; Danckert, James; Blangero, Annabelle; Rossetti, Yves

    2007-04-09

    Visual illusions have been shown to affect perceptual judgements more so than motor behaviour, which was interpreted as evidence for a functional division of labour within the visual system. The dominant perception-action theory argues that perception involves a holistic processing of visual objects or scenes, performed within the ventral, inferior temporal cortex. Conversely, visuomotor action involves the processing of the 3D relationship between the goal of the action and the body, performed predominantly within the dorsal, posterior parietal cortex. We explored the effect of well-known visual illusions (a size-contrast illusion and the induced Roelofs effect) in a patient (IG) suffering bilateral lesions of the dorsal visual stream. According to the perception-action theory, IG's perceptual judgements and control of actions should rely on the intact ventral stream and hence should both be sensitive to visual illusions. The finding that IG performed similarly to controls in three different illusory contexts argues against such expectations and shows, furthermore, that the dorsal stream does not control all aspects of visuomotor behaviour. Assuming that the patient's dorsal stream visuomotor system is fully lesioned, these results suggest that her visually guided action can be planned and executed independently of the dorsal pathways, possibly through the inferior parietal lobule.

  11. Posterior cortical atrophy - a prototypical case of dementia beginning with visual symptoms: case report

    Directory of Open Access Journals (Sweden)

    Leonardo Ferreira Caixeta

    2013-10-01

    Full Text Available Dementia presenting with prominent higher order visual symptoms may be observed in a range of neurodegenerative conditions and is often challenging to diagnose. We describe a case of progressive dementia presenting with prominent visual cortical symptoms. A 55-year-old, right-handed, woman with early onset of visual impairment not associated with anterior visual pathology, presenting with dyslexia, visual agnosia, Balint's syndrome, and spatial disorientation. Ophthalmologists should consider this condition especially in presenile patients with slowly progressive higher-order visual symptoms. Although described in association with different conditions, it may also occur in Alzheimer disease.

  12. Posterior cortical atrophy--a prototypical case of dementia beginning with visual symptoms: case report.

    Science.gov (United States)

    Caixeta, Leonardo Ferreira; Taleb, Alexandre Chater; Ghini, Bruno Galafassi; Soares, Vânia Lúcia Dias; Caixeta, Victor de Melo; Vargas, Ciro

    2013-10-01

    Dementia presenting with prominent higher order visual symptoms may be observed in a range of neurodegenerative conditions and is often challenging to diagnose. We describe a case of progressive dementia presenting with prominent visual cortical symptoms. A 55-year-old, right-handed, woman with early onset of visual impairment not associated with anterior visual pathology, presenting with dyslexia, visual agnosia, Balint's syndrome, and spatial disorientation. Ophthalmologists should consider this condition especially in presenile patients with slowly progressive higher-order visual symptoms. Although described in association with different conditions, it may also occur in Alzheimer disease.

  13. Refinement but not maintenance of visual receptive fields is independent of visual experience.

    Science.gov (United States)

    Balmer, Timothy S; Pallas, Sarah L

    2015-04-01

    Visual deprivation is reported to prevent or delay the development of mature receptive field (RF) properties in primary visual cortex (V1) in several species. In contrast, visual deprivation neither prevents nor delays refinement of RF size in the superior colliculus (SC) of Syrian hamsters, although vision is required for RF maintenance in the SC. Here, we report that, contrary to expectation, visual cortical RF refinement occurs normally in dark-reared animals. As in the SC, a brief period of visual experience is required to maintain V1 RF refinement in adulthood. Whereas in the SC, 3 days of visual experience within a sensitive period (P37-40) was sufficient to protect RFs from deprivation-induced enlargement in adulthood, 7 days (P33-40) were required for RF size maintenance in V1. Thus, spontaneous activity is sufficient for RF refinement at these 2 levels of the visual pathway, and visual input is necessary only to prevent deprivation-induced RF enlargement in adulthood. These studies show that sensory experience during a late juvenile sensitive period protects the visual pathway against sensory deprivation in adulthood, and suggest that more importance may have been placed on the role of early visual experience in visual RF development than is warranted.

  14. Characterization of rat model of acute anterior uveitis using optical coherence tomography angiography

    Science.gov (United States)

    Choi, Woo June; Pepple, Kathryn L.; Zhi, Zhongwei; Wang, Ruikang K.

    2015-03-01

    Uveitis, or ocular inflammation, is a cause of severe visual impairment. Rodent models of uveitis are powerful tools used to investigate the pathological mechanisms of ocular inflammation and to study the efficacy of new therapies prior to human testing. In this paper, we report the utility of spectral-domain optical coherence tomography (SD-OCT) angiography in characterizing the inflammatory changes induced in the anterior segment of a rat model of uveitis. Acute anterior uveitis (AAU) was induced in two rats by intravitreal injection of a killed mycobacterial extract. One of them received a concurrent periocular injection of steroids to model a treatment effect. OCT imaging was performed prior to inflammation induction on day 0 (baseline), and 2 days post-injection (peak inflammation). Baseline and inflamed images were compared. OCT angiography identified swelling of the cornea, inflammatory cells in the anterior and posterior chambers, a fibrinous papillary membrane, and dilation of iris vessels in the inflamed eyes when compared to baseline images. Steroid treatment was shown to prevent the changes associated with inflammation. This is a novel application of anterior OCT imaging in animal models of uveitis, and provides a high resolution, in vivo assay for detecting and quantifying ocular inflammation and the response to new therapies.

  15. Results of cataract surgery and plasma ablation posterior capsulotomy in anterior persistent hyperplastic primary vitreous

    Directory of Open Access Journals (Sweden)

    Rajesh Sinha

    2013-01-01

    Full Text Available Purpose: To report the feasibility and outcome of lens aspiration, and Fugo blade-assisted capsulotomy and anterior vitrectomy in eyes with anterior persistent hyperplastic primary vitreous (PHPV. Materials and Methods: In this case series, 10 eyes of 10 patients with anterior PHPV underwent lens aspiration. The vascularized posterior capsule was cut with a Fugo blade (plasma knife and removed with a vitrector. A foldable posterior chamber intraocular lens (IOL was implanted in eight eyes and the outcomes were evaluated. Results: The mean age of patients was 16.8 ± 6.37 months (range: 5 to 28 months. The surgery was completed successfully in all eyes. There were no cases of intraocular hemorrhage intraoperatively. Foldable acrylic IOL was implanted in the bag in 3 eyes and in the sulcus in 5 eyes. Two eyes were microphthalmic and did no undergo IOL implantation (aphakic. None of the eyes had a significant reaction or elevated intraocular pressure postoperatively. The follow-up ranged from 4 to 21 months. All the pseudophakic eyes achieved a best corrected visual acuity of ≥20/200 with 50% (4/8 of these eyes with ≥20/60 vision. Conclusion: Lens aspiration followed by posterior capsulotomy with Fugo blade-assisted plasma ablation is a feasible technique for performing successful lens surgery in cases with florid anterior PHPV.

  16. Visual fields in neuro-ophthalmology.

    Science.gov (United States)

    Kedar, Sachin; Ghate, Deepta; Corbett, James J

    2011-01-01

    Visual field assessment is important in the evaluation of lesions involving the visual pathways and should be performed at baseline and periodically in the follow-up. Standard automated perimetry has been shown to be adequate in neuro-ophthalmic practise and is now the technique of choice for a majority of practitioners. Goldman kinetic visual fields are useful for patients with severe visual and neurologic deficits and patients with peripheral visual field defects. Visual fields are useful in monitoring progression or recurrence of disease and guide treatment for conditions such as idiopathic intracranial hypertension (IIH), optic neuropathy from multiple sclerosis, pituitary adenomas, and other sellar lesions. They are used as screening tools for toxic optic neuropathy from medications such as ethambutol and vigabatrin. Visual field defects can adversely affect activities of daily living such as personal hygiene, reading, and driving and should be taken into consideration when planning rehabilitation strategies. Visual field testing must be performed in all patients with lesions of the visual pathway.

  17. Femtosecond laser-assisted deep anterior lamellar keratoplasty for keratoconus and keratectasia

    Institute of Scientific and Technical Information of China (English)

    Yan; Lu; Yu-Hua; Shi; Li-Ping; Yang; Yi-Rui; Ge; Xiang-Fei; Chen; Yan; Wu; Zhen-Ping; Huang

    2014-01-01

    ·AIM: To describe the initial outcomes and safety of femtosecond laser-assisted deep anterior lamellar keratoplasty(DALK) for keratoconus and post-LASIK keratectasia.·METHODS: In this non-comparative case series, 10 eyes of 9 patients underwent DALK procedures with a femtosecond laser(Carl Zeiss Meditec AG, Jena,Germany). Of the 9 patients, 7 had keratoconus and 2had post-LASIK keratectasia. A 500 kHz VisuMax femtosecond laser was used to perform corneal cuts on both donor and recipient corneas. The outcome measures were the uncorrected visual acuity(UCVA),best-corrected visual acuity(BCVA), corneal thickness,astigmatism, endothelial density count(EDC), and corneal power.·RESULTS: All eyes were successfully treated. Early postoperative evaluation showed a clear graft in all cases. Intraoperative complications included one case of a small Descemet’s membrane perforation.Postoperatively, there was one case of stromal rejection,one of loosened sutures, and one of wound dehiscence.A normal corneal pattern topography and transparency were restored, UCVA and BCVA improved significantly,and astigmatism improved slightly. There was no statistically significant decrease in EDC.· CONCLUSION: Our early results indicate that femtosecond laser-assisted deep anterior lamellar keratoplasty could improve UCVA and BCVA in patients with anterior corneal pathology. This approach shows promise as a safe and effective surgical choice in the treatment of keratoconus and post-LASIK keratectasia.

  18. Visual rehabilitation: visual scanning, multisensory stimulation and vision restoration trainings

    Directory of Open Access Journals (Sweden)

    Neil M. Dundon

    2015-07-01

    Full Text Available Neuropsychological training methods of visual rehabilitation for homonymous vision loss caused by postchiasmatic damage fall into two fundamental paradigms: compensation and restoration. Existing methods can be classified into three groups: Visual Scanning Training (VST, Audio-Visual Scanning Training (AViST and Vision Restoration Training (VRT. VST and AViST aim at compensating vision loss by training eye scanning movements, whereas VRT aims at improving lost vision by activating residual visual functions by training light detection and discrimination of visual stimuli. This review discusses the rationale underlying these paradigms and summarizes the available evidence with respect to treatment efficacy. The issues raised in our review should help guide clinical care and stimulate new ideas for future research uncovering the underlying neural correlates of the different treatment paradigms. We propose that both local within-system interactions (i.e., relying on plasticity within peri-lesional spared tissue and changes in more global between-system networks (i.e., recruiting alternative visual pathways contribute to both vision restoration and compensatory rehabilitation that ultimately have implications for the rehabilitation of cognitive functions.

  19. Multiple Visual Field Representations in the Visual Wulst of a Laterally Eyed Bird, the Zebra Finch (Taeniopygia guttata)

    Science.gov (United States)

    2016-01-01

    The visual wulst is the telencephalic target of the avian thalamofugal visual system. It contains several retinotopically organised representations of the contralateral visual field. We used optical imaging of intrinsic signals, electrophysiological recordings, and retrograde tracing with two fluorescent tracers to evaluate properties of these representations in the zebra finch, a songbird with laterally placed eyes. Our experiments revealed that there is some variability of the neuronal maps between individuals and also concerning the number of detectable maps. It was nonetheless possible to identify three different maps, a posterolateral, a posteromedial, and an anterior one, which were quite constant in their relation to each other. The posterolateral map was in contrast to the two others constantly visible in each successful experiment. The topography of the two other maps was mirrored against that map. Electrophysiological recordings in the anterior and the posterolateral map revealed that all units responded to flashes and to moving bars. Mean directional preferences as well as latencies were different between neurons of the two maps. Tracing experiments confirmed previous reports on the thalamo-wulst connections and showed that the anterior and the posterolateral map receive projections from separate clusters within the thalamic nuclei. Maps are connected to each other by wulst intrinsic projections. Our experiments confirm that the avian visual wulst contains several separate retinotopic maps with both different physiological properties and different thalamo-wulst afferents. This confirms that the functional organization of the visual wulst is very similar to its mammalian equivalent, the visual cortex. PMID:27139912

  20. Multiple Visual Field Representations in the Visual Wulst of a Laterally Eyed Bird, the Zebra Finch (Taeniopygia guttata.

    Directory of Open Access Journals (Sweden)

    Hans-Joachim Bischof

    Full Text Available The visual wulst is the telencephalic target of the avian thalamofugal visual system. It contains several retinotopically organised representations of the contralateral visual field. We used optical imaging of intrinsic signals, electrophysiological recordings, and retrograde tracing with two fluorescent tracers to evaluate properties of these representations in the zebra finch, a songbird with laterally placed eyes. Our experiments revealed that there is some variability of the neuronal maps between individuals and also concerning the number of detectable maps. It was nonetheless possible to identify three different maps, a posterolateral, a posteromedial, and an anterior one, which were quite constant in their relation to each other. The posterolateral map was in contrast to the two others constantly visible in each successful experiment. The topography of the two other maps was mirrored against that map. Electrophysiological recordings in the anterior and the posterolateral map revealed that all units responded to flashes and to moving bars. Mean directional preferences as well as latencies were different between neurons of the two maps. Tracing experiments confirmed previous reports on the thalamo-wulst connections and showed that the anterior and the posterolateral map receive projections from separate clusters within the thalamic nuclei. Maps are connected to each other by wulst intrinsic projections. Our experiments confirm that the avian visual wulst contains several separate retinotopic maps with both different physiological properties and different thalamo-wulst afferents. This confirms that the functional organization of the visual wulst is very similar to its mammalian equivalent, the visual cortex.

  1. Molecular pathways

    DEFF Research Database (Denmark)

    Cox, Thomas R; Erler, Janine Terra

    2014-01-01

    that 45% of deaths in the developed world are linked to fibrotic disease. Fibrosis and cancer are known to be inextricably linked; however, we are only just beginning to understand the common and overlapping molecular pathways between the two. Here, we discuss what is known about the intersection...... of fibrosis and cancer, with a focus on cancer metastasis, and highlight some of the exciting new potential clinical targets that are emerging from analysis of the molecular pathways associated with these two devastating diseases. Clin Cancer Res; 20(14); 3637-43. ©2014 AACR....

  2. Surgical Management of Intramyocardial Left Anterior Descending Artery.

    Science.gov (United States)

    De Salvatore, Sergio; Segreto, Antonio; Chiusaroli, Alessandro; Congiu, Stefano; Bizzarri, Federico

    2015-11-01

    An intramyocardial left anterior descending artery can be found in up to 30% of patients undergoing coronary artery bypass graft procedures. We review the various techniques available to identify an intramyocardial left anterior descending artery.

  3. Six3, a medaka homologue of the Drosophila homeobox gene sine oculis is expressed in the anterior embryonic shield and the developing eye.

    Science.gov (United States)

    Loosli, F; Köster, R W; Carl, M; Krone, A; Wittbrodt, J

    1998-06-01

    homologue Six3 (Oliver, G., Mailhos, A., Wehr, R., Copeland, N.G., Jenkins, N.A., Gruss, P., 1995. Six3, a murine homologue of the sine oculis gene, demarcates the most anterior border of the developing neural plate and is expressed during eye development. Development 121, 4045-4055). sine oculis (so) is essential for the development of the larval and adult visual system (Cheyette, B.N.R., Green, P.J., Martin, K., Garren, H., Hartenstein, V., Zipursky, S.L., 1994. The Drosophila sine oculis locus encodes a homeodomain-containing protein required for the development of the entire visual system. Neuron l2, 977-996). Six3 is expressed in the anterior neural plate and optic vesicles, lens, olfactory placodes and ventral forebrain (Oliver, G., Mailhos, A., Wehr, R., Copeland, N.G., Jenkins, N.A., Gruss, P., 1995. Six3, a murine homologue of the sine oculis gene, demarcates the most anterior border of the developing neural plate and is expressed during eye development. Development 121, 4045-4055). Overexpression of mouse Six3 gene in medaka fish embryos (Orvzias latipes) results in the formation of an ectopic lens, indicating that Six3 activity can trigger the genetic pathway leading to lens formation (Oliver, G., Loosli, F., Koster, R., Wittbrodt, J., Gruss, P., 1996. Ectopic lens induction in fish in response to the murine homeobox gene Six3. Mech. Dev. 60, 233-239). We isolated the medaka Six3 homologue and analyzed its expression pattern in the medaka embryo. It is expressed initially in the anterior embryonic shield and later in the developing eye and prosencephalon. The early localized expression of Six3 suggests a role in the regionalization of the rostral head.

  4. Visual Impairment Due to Lissencephaly

    OpenAIRE

    Marqués-Fernández, V. E.; Sánchez-Tocino, H.; Escudero-Caro, M.T.; Cancho-Candela, R.; García-Zamora, M.

    2016-01-01

    Lissencephaly is a rare disorder due to abnormal neural migration, causing neurological impairment and clinically characterised by mental retardation and epilepsy. Any disturbance of the visual pathway can cause loss of vision. The authors describe a case of a 6-year-old boy referred to the ophthalmologist presenting poor bilateral vision. This child had no other known medical conditions, and neurological examination was completely normal. Only when a magnetic resonance imaging was made that ...

  5. Surgical treatment of anterior cruciate ligament injury in adults.

    Science.gov (United States)

    Alazzawi, Sulaiman; Sukeik, Mohamed; Ibrahim, Mazin; Haddad, Fares S

    2016-04-01

    Anterior cruciate ligament injury is among the most common soft tissue injuries of the knee joint and reconstruction of the anterior cruciate ligament is the gold standard treatment for young active symptomatic patients. This review summarizes the surgical treatment of anterior cruciate ligament injury.

  6. [Esthetic restorations of primary anterior teeth].

    Science.gov (United States)

    Elqadir, A Jamil; Shapira, J; Ziskind, K; Ram, D

    2013-04-01

    Esthetic treatment of primary teeth is one of the greatest challenges to pediatric dentists. A variety of restorative options using full coverage are available for anterior primary teeth. In the last half century the emphasis on treatment of severely decayed primary teeth shifted from extraction to restoration. In the past, restorations consisted of placement of stainless steel crowns on severely decayed teeth. However, they are esthetically unacceptable today. Over the last decade parents expect a higher esthetic standard for their children's primary teeth. Thus, the restoration should provide esthetic appearance and durability in addition to restoring function. The purpose of this review is to describe the types of full coverage options for anterior primary teeth currently available.

  7. Displaced fracture through the anterior atlantal synchondrosis

    Energy Technology Data Exchange (ETDEWEB)

    Thakar, Chrishan; Allibone, James [Royal National Orthopaedic Hospital NHS Trust, Department of Spinal Deformity, Stanmore, Middlesex (United Kingdom); Harish, Srinivasan [Royal National Orthopaedic Hospital NHS Trust, Department of Radiology, Stanmore, Middlesex (United Kingdom); Saifuddin, Asif [Royal National Orthopaedic Hospital NHS Trust, Department of Radiology, Stanmore, Middlesex (United Kingdom); University College, The Institute of Orthopaedics and Musculoskeletal Sciences, London (United Kingdom)

    2005-09-01

    In the acute setting, accurate radiological interpretation of paediatric cervical spine trauma can be difficult due to a combination of normal variants and presence of multiple synchondroses. We present a rare case of a fracture through the anterior atlantal synchondrosis in a paediatric spine. A five-year-old boy, who fell backwards onto the top of his head while swinging across on a monkey bar frame, presented with neck pain, cervical muscle spasm and decreased right lateral rotation and extension of his neck. Computed tomography showed a displaced diastatic fracture through right anterior atlantal synchondrosis. There are only 12 cases of paediatric C1 fractures reported in the world literature. The importance of considering this diagnosis in the appropriate clinical setting, and the normal variants in the paediatric atlas that can cause diagnostic dilemma to the interpreting radiologist, are discussed in this case report. (orig.)

  8. Anterior uveitis in juvenile rheumatoid arthritis.

    Science.gov (United States)

    Kanski, J J

    1977-10-01

    The ocular and systemic characteristics of 160 patients with anterior uveitis and seronegative juvenile rheumatoid arthritis are reviewed. Chronic uveitis occurred in 131 patients, 76% of whom were girls. Both eyes were involved in 70% of the cases. Band keratopathy occurred in 41% of the eyes, cataract in 42%, and secondary glaucoma in 19%. Only 11 patients had uveitis before the onset of arthritis. Notable correlations included a pauciarticular onset of arthritis in 95% of the patients, and positive tests for antinuclear antibody in 82%. Of 29 patients with acute anterior uveitis, 27 were boys. The inflammation responded well to therapy, and serious complications did not occur. At follow-up 21 patients had typical ankylosing spondylitis, and five had sacroiliitis. The incidence of positive results of tests for HLA-B27 antigen was 94%.

  9. Refining the Indications for the Addition of Orbital Osteotomy during Anterior Cranial Base Approaches: Morphometric and Radiologic Study of the Anterior Cranial Base Osteology.

    Science.gov (United States)

    DeBattista, Juan Carlos; Andaluz, Norberto; Zuccarello, Mario; Kerr, Robert G; Keller, Jeffrey T

    2014-08-01

    Objectives In anatomic and radiologic morphometric studies, we examine a predictive method, based on preoperative imaging of the anterior cranial base, to define when addition of orbital osteotomy is warranted. Design Anatomic and radiographic study. Setting In 100 dry skulls, measurements in the anterior cranial fossa included three lines and two angles based on computerized tomography (CT) scans taken in situ and validated using frameless stereotactic navigation. The medial angle (coronal plane) was the intersection between the highest point of both orbits and the midpoint between the two frontoethmoidal sutures to each orbital roof high point. The oblique angle (sagittal plane) was the intersection at the midpoint of the limbus sphenoidale. Results No identifiable morphometric patterns were found for our classification of anterior fossae; the two-tailed distribution pattern was similar for all skulls, disproving the hypothetical correlation between visual appearance and morphometry. Orbital heights (range: 6.6-18.7 mm) showed a linear relationship with medial and oblique angles, and they had a linear distribution relative to angular increments. Orbital heights > 11 mm were associated with angles ≥ 20 degrees and more likely to benefit from orbitotomy. Conclusion Preoperative CT measurement of orbital height appears feasible for predicting when orbitotomy is needed, and it warrants further testing.

  10. The adhesion GPCR latrophilin - a novel signaling cascade in oriented cell division and anterior-posterior polarity.

    Science.gov (United States)

    Winkler, Jana; Prömel, Simone

    2016-01-01

    Although several signaling pathways in oriented cell division have been well characterized such as delta/notch inductions or wnt/frizzled-based anterior-posterior polarity, there is strong evidence for additional signal pathways controlling early anterior-posterior polarity decisions. The homolog of the adhesion G protein-coupled receptor latrophilin, LAT-1 has been identified as a receptor essential for oriented cell division in an anterior-posterior direction of specific blastomeres in the early C. elegans embryo. We recently conducted a study aiming at clarifying the signals involved in LAT-1 function. We identified a Gs protein/adenylyl cyclase/cAMP pathway in vitro and demonstrated its physiological relevance in oriented cell division. By interaction with a Gs protein LAT-1 elevates cAMP levels. These data indicate that G-protein signaling in oriented cell division is not solely GPCR-independent. This commentary will discuss our findings in the context of the current knowledge of mechanisms controlling oriented cell division and anterior-posterior polarity. Further, we identify open questions which need to be addressed in the future.

  11. Anterior Tibial Artery Pseudoaneurysm: Case Report

    Directory of Open Access Journals (Sweden)

    Funda Tor

    2012-06-01

    Full Text Available The aneurysmsatic changes of the infrapopliteal arteries are rarely seen. They are pseudoaneurysms rather than true aneursyms. The most important cause of them is trauma. There is not a standart treatment for infrapopliteal aneursyms. In this study, we have evaluated a case operated for anterior tibial artery pseudoaneurysm developed after penetrant trauma and diagnosed two weeks later. [Cukurova Med J 2012; 37(3.000: 172-175

  12. Anterior sacral meningocele presenting as constipation

    Directory of Open Access Journals (Sweden)

    Anup Mohta

    2011-01-01

    Full Text Available Anterior sacral meningocele (ASM is a rare form of spinal dysraphism in children. Usually asymptomatic, it can present as constipation, urinary problems or rarely neurological symptoms. High index of suspicion with careful clinical examination is necessary to make early diagnosis. Magnetic resonance imaging is the investigation of choice. We describe a successfully managed young child with ASM associated with rib and vertebral defects.

  13. Can they really be opposite? A new look at four critical aspects of anterior dental morphology.

    Science.gov (United States)

    Greenberg, Joseph R

    2008-09-01

    Human dental anatomy has not changed significantly in hundreds of years. Dental students and students of dental laboratory technology learn human dental anatomy as fundamental to their didactic work. Yet, so often we see dental restorations that do not follow the accepted basic design criteria of natural teeth. A possible conclusion is that the information was correctly presented as a basic science, but not completely carried over into clinical practice. When visually essential aspects of dental anatomy and composition are not accurately incorporated into esthetic restorations, patients are not completely served, and practitioners may be frustrated as well. This article reviews four essential aspects of anterior dental morphology--anterior tooth width/length proportions, bilateral symmetry, incisal edges, and incisal embrasures--that often are not accurately incorporated into dental restorations, and positions them in an easy to remember format: opposites.

  14. The Retinal Nerve Fiber Layer Defects in Patients with Anterior Ischemic Optic Neuropathy

    Institute of Scientific and Technical Information of China (English)

    HaiLu; QiZang

    1995-01-01

    Purpose:To demonstrate the effects of optic nerve ischemia on retinal nerve fiber layer(RNFL)and the associated visual dysfunction.Methods:23patients(25eyes)wits anterior ischemic optic neuropathy(AION)un derwent fundus fluorescein angiography(FFA),and then red-foree light pic-tures were taken via SE-40exceiter filter.All pictures were printed for RNAFL analysis,Humphrey central field analysis was conducted.All dataobtained fromFFA and visual field defects were analysed statistically.Results:The RNFL defects and the corresponding visual field edfects were pre-sented in 23of 25eyes(92%),The optic disc filling defects,RNAL edfects and visual field defects were found to be highly correspondent to each other.The RNFL defects were mainly the local losses of RNFL which were correspondent to the ischemic regions.Conclusion:The poor optic disc filling or ischemia can result in the RNFL defects which cause the associated visual dysfunction.Because RNFLdefects are irrever-siable changes,the potential values in predicting the prognosis of visual field de-fects caused by RNFL damages were suggested.Eye Science1995;11:165-167.

  15. The use of EMG biofeedback for learning of selective activation of intra-muscular parts within the serratus anterior muscle: a novel approach for rehabilitation of scapular muscle imbalance.

    Science.gov (United States)

    Holtermann, A; Mork, P J; Andersen, L L; Olsen, H B; Søgaard, K

    2010-04-01

    Motor control and learning possibilities of scapular muscles are of clinical interest for restoring scapular muscle balance in patients with neck and shoulder disorders. The aim of the study was to investigate whether selective voluntary activation of intra-muscular parts within the serratus anterior can be learned with electromyographical (EMG) biofeedback, and whether the lower serratus anterior and the lower trapezius muscle comprise the lower scapula rotation force couple by synergistic activation. Nine healthy males practiced selective activation of intra-muscular parts within the serratus anterior with visual EMG biofeedback, while the activity of four parts of the serratus anterior and four parts of the trapezius muscle was recorded. One subject was able to selectively activate both the upper and the lower serratus anterior respectively. Moreover, three subjects managed to selectively activate the lower serratus anterior, and two subjects learned to selectively activate the upper serratus anterior. During selective activation of the lower serratus anterior, the activity of this muscle part was 14.4+/-10.3 times higher than the upper serratus anterior activity (P<0.05). The corresponding ratio for selective upper serratus vs. lower serratus anterior activity was 6.4+/-1.7 (P<0.05). Moreover, selective activation of the lower parts of the serratus anterior evoked 7.7+/-8.5 times higher synergistic activity of the lower trapezius compared with the upper trapezius (P<0.05). The learning of complete selective activation of both the lower and the upper serratus anterior of one subject, and selective activation of either the upper or lower serratus anterior by five subjects designates the promising clinical application of EMG biofeedback for restoring scapular muscle balance. The synergistic activation between the lower serratus anterior and the lower trapezius muscle was observed in only a few subjects, and future studies including more subjects are required

  16. TOXIC ANTERIOR SEGMENT SYNDROME (TASS WITH SEVERE PIGMENT DISPERSION

    Directory of Open Access Journals (Sweden)

    Stephen Sudhakar

    2014-09-01

    Full Text Available AIM: To clinically analyze the cases of TASS with severe pigment dispersion following uncomplicated cataract surgery in a tertiary care teaching hospital from January 2011 to January 2013. DESIGN: Retrospective case series study. MATERIALS AND METHODS: The records of all eyes developing TASS with severe pigment dispersion following uncomplicated Cataract surgery were retrospectively reviewed. Clinical outcomes including visual acuity, intraocular pressure and complications were recorded at 1st post-operative day, 7th post-operative day and after six weeks of follow up visits. RESULTS: TASS with severe pigment dis pension was recorded in five out of 1060 patients. All cases were females. Phacoemulsification with foldable IOL was done in 2 patients and Small Incision Cataract Surgery (SICS with in bag posterior chamber IOL was done in three patients. All patients had pain which was less severe when compared to the amount of inflammation. Visual acuity ranged from 6/36 to perception of light. All the five patients had rim to rim corneal edema which was seen from the first post-operative day and persisted at six weeks follow up. Pupils were dilated and fixed in all patients. Intraocular pressure was raised in four out of five patients who poorly responded to medical treatment. Dense pigment clumps were seen in the corneal endothelium and on the surgical wound site after one week in three out of five patients and increased at 6 weeks of follow up. Visual acuity did not improve in any of the patient even with treatment. The reduced visual acuity was due to worsening corneal edema and dense pigment clumping in corneal endothelium. CONCLUSION: TASS with severe pigment dispersion has more complication than routine TASS. The complication are due to dense pigment clumping in cornea and angle of anterior chamber causing corneal endothelial de-compensation and raised Intraocular pressure, which persisted even after the inflammation subsided. Although the

  17. [Intraoperative Visual Evoked Potential Monitoring].

    Science.gov (United States)

    Hayashi, Hironobu; Kawaguchi, Masahiko

    2015-05-01

    Visual evoked potential (VEP) is recorded from the back of the head, which is elicited by retinal stimulation transmitted through optic nerve, optic chiasm, optic tract lateral geniculate body, optic radiation and finally cortical visual area. VEP monitoring did not prevail since 1990s because marked intra-individual difference and instability of VEP recording limited the clinical usefulness under inhalation anesthetic management and techniques of VEP monitoring at the time. However, recent advances in techniques including a new light-stimulating device consisting of high-luminosity LEDs and induction of electroretinography to ascertain the arrival of the stimulus at the retina provided better conditions for stable VEP recording under general anesthesia. In addition, the introduction of total intravenous anesthesia using propofol is important for the successful VEP recordings because inhaled anesthetics have suppressive effect on VEP waveform. Intraoperative VEP has been considered to monitor the functional integrity of visual function during neurosurgical procedures, in which the optic pathway is at a risk of injury. Intraoperative VEP monitoring may allow us to detect reversible damage to the visual pathway intraoperatively and enable us to prevent permanent impairment.

  18. Modulation of visually evoked postural responses by contextual visual, haptic and auditory information: a 'virtual reality check'.

    Directory of Open Access Journals (Sweden)

    Georg F Meyer

    Full Text Available Externally generated visual motion signals can cause the illusion of self-motion in space (vection and corresponding visually evoked postural responses (VEPR. These VEPRs are not simple responses to optokinetic stimulation, but are modulated by the configuration of the environment. The aim of this paper is to explore what factors modulate VEPRs in a high quality virtual reality (VR environment where real and virtual foreground objects served as static visual, auditory and haptic reference points. Data from four experiments on visually evoked postural responses show that: 1 visually evoked postural sway in the lateral direction is modulated by the presence of static anchor points that can be haptic, visual and auditory reference signals; 2 real objects and their matching virtual reality representations as visual anchors have different effects on postural sway; 3 visual motion in the anterior-posterior plane induces robust postural responses that are not modulated by the presence of reference signals or the reality of objects that can serve as visual anchors in the scene. We conclude that automatic postural responses for laterally moving visual stimuli are strongly influenced by the configuration and interpretation of the environment and draw on multisensory representations. Different postural responses were observed for real and virtual visual reference objects. On the basis that automatic visually evoked postural responses in high fidelity virtual environments should mimic those seen in real situations we propose to use the observed effect as a robust objective test for presence and fidelity in VR.

  19. Anterior Uveitis Caused by Ocular Side Effects of Afatinib: A Case Report

    Directory of Open Access Journals (Sweden)

    Daisuke Todokoro

    2016-02-01

    Full Text Available Afatinib is a second-generation epidermal growth factor receptor (EGFR inhibitor that has been shown to be effective against EGFR-mutated non-small cell lung cancer (NSCLC resistant to conventional EGFR inhibitors such as gefitinib and erlotinib. Although ocular side effects of gefitinib and erlotinib have been reported, those for afatinib have yet to be definitively established. This report presents details on the first case of unilateral iridocyclitis associated with the side effects of afatinib therapy. A 75-year-old Japanese male ex-smoker with EGFR-mutated NSCLC underwent afatinib therapy for multiple metastases. At 2 weeks, bilateral conjunctivitis developed. Topical medication and a 1-week afatinib washout period resulted in the improvement of the conjunctivitis. However, 3 days after the resumption of afatinib, the patient developed unilateral granulomatous anterior uveitis in his right eye. Best-corrected visual acuity (BCVA measurement indicated a decimal visual acuity of 0.2, while the slit-lamp findings were characterized by granulomatous inflammation, keratic precipitates, Koeppe nodules and posterior synechiae. There was no evidence suggesting other intraocular inflammatory disease or metastatic tumor. The left eye was intact. The use of topical medication including steroids and a washout of afatinib resulted in a gradual subsiding of the anterior uveitis. After resolution of the anterior uveitis, oral afatinib was resumed. BCVA of the right eye finally recovered to a decimal acuity of 1.0. Ophthalmologists should be aware of the possibility that side effects associated with afatinib could cause granulomatous anterior uveitis.

  20. Remaining visual field and preserved subjective visual functioning prevent mental distress in patients with visual field defects

    Directory of Open Access Journals (Sweden)

    Carolin eGall

    2013-09-01

    Full Text Available Background: Patients with visual field defects after visual pathway lesion may experience reduced vision-related quality of life (vrQoL. It has not been clarified how vrQoL impairments contribute to vision-related mental distress.Methods: 108 subjects with visual field defects caused by optic neuropathies (age M=57.6; SD=13.7 years answered the National Eye Institute Visual-Functioning Questionnaire (NEI-VFQ for vrQoL and the SF-12 Short Form Health Survey for health-related quality of life (hrQoL. A ten item composite of NEI-VFQ visual functioning and five items of mental health symptoms due to vision problems were subjected to Rasch analysis. The test battery comprised static and High Resolution Perimetry (HRP. Regression and path analysis were used to investigate associations between QoL, mental distress and perimetry results.Results: A higher level of visual functioning was associated with monocular impairment and a larger remaining visual field compared to binocular impairment. Subjective visual functioning but not visual field parameters predicted mental health symptoms due to vision problems which was the only variable associated with the SF-12 mental component score. The SF-12 physical component score was less strongly associated with mental health symptoms due to vision problems. Here, reaction time in HRP and mean threshold in perimetry were additional significant variables. Path analysis revealed a significant path of remaining visual field via visual functioning on mental health. Conclusions: Subjective consequences of visual impairments in everyday life impact mental health rather than objective visual function loss as measured by perimetry. Since a higher extent of vrQoL was related to lower levels of mental distress, the maintenance of vrQoL could reduce and prevent mental distress due to vision problems. Patients with persisting visual field defects may benefit from neuropsychological rehabilitation and supportive therapies.

  1. Anterior ischemic optic neuropathy associated with metabolic syndrome Neuropatia óptica isquêmica anterior associada a síndrome metabólica

    Directory of Open Access Journals (Sweden)

    Natalija Kosanovic-Jakovic

    2008-02-01

    Full Text Available PURPOSE: Metabolic syndrome denotes a common cluster of naturally connected risk factors including obesity, elevated blood pressure, insulin resistance, dyslipidemia, proinflammatory state and prothrombotic state. Anterior ischemic optic neuropathy is an acute ischaemic disorder of the optic nerve head and may lead to severe visual loss. METHODS: We considered three patients with moderate degree of diabetic retinopathy and anterior ischemic optic neuropathy. They were submitted to endocrinological examination and the diagnosis of metabolic syndrome was established. RESULTS: Cardiological examination revealed that blood pressure control was not optimal. The signs of left ventricular hypertrophy and diastolic dysfunction were confirmed by echocardiography. They are possible markers of preclinical cardiovascular disease. CONCLUSION: We observed that a variety of well-known risk factors in metabolic syndrome may be involved in serious eye and cardiological complications. The early diagnosis and treatment of these patients can not only improve visual function but also prevent cardiovascular complications.OBJETIVO: A síndrome metabólica indica um grupo comum dos seguintes achados clinicos: obesidade, hipertensão arterial, variações nos níveis de glicemia, dislipidemia, estado proinflamatório e o estado protrombótico. Neuropatia óptica isquêmica anterior é um distúrbio agudo isquêmico da cabeça do nervo óptico que pode levar à perda de visão. MÉTODOS: Consideramos três pacientes com retinopatia diabética não proliferativa moderada e neuropatia óptica isquêmica anterior. Os pacientes foram examinados por endocrinologistas e o diagnóstico de síndrome metabólica foi confirmado. RESULTADOS: O exame cardiológico revelou que o controle da pressão sangüínea não era adequado e tal anormalidade foi corrigida. A ecocardiografia confirmou os indícios de hipertrofia ventricular esquerda e disfunção diastólica. Estes são os

  2. Magnetic Resonance Imaging (MRI) Evaluation for Anterior Disc Displacement of the Temporomandibular Joint

    Science.gov (United States)

    Yang, Zhongjun; Wang, Mingguo; Ma, Yingwei; Lai, Qingguo; Tong, Dongdong; Zhang, Fenghe; Dong, Lili

    2017-01-01

    Background Magnetic resonance imaging (MRI) is the criterion standard imaging technique for visualization of the temporomandibular joint (TMJ) region, and is currently considered the optimum modality for comprehensive evaluation in patients with temporomandibular joint disorder (TMD). This study was aimed at finding the value of MRI in pre-clinical diagnosis of TMJ disc displacement. Material/Methods Patients primarily diagnosed as having anterior disc displacement by clinical symptoms and X-ray were selected in the present study. MRI was used to evaluate surrounding anatomical structures and position, as well as morphological and signal intensity change between patients and normal controls. Results Posterior band position was significantly different between the patient group and control group. At the maximum opened-mouth position, the location of disc intermediate zone returned to normal. At closed-mouth position, the thickness of anterior and middle, but not posterior, band increased. The motion range of the condyle in the anterior disc displacement without reduction (ADDWR) patient group was significantly less than the value in the anterior disc displacement with reduction (ADDR) patient group and the control group. Whether at closed-mouth position or maximum opened-mouth position, the exudate volume in the patient group was greater than in the normal group. Conclusions MRI can be successfully used to evaluate multiple morphological changes at different mouth positions of normal volunteers and patients. The disc-condyle relationship can serve as an important indicator in assessing anterior disc displacement, and can be used to distinguish disc displacement with or without reduction. PMID:28176754

  3. Visualization rhetoric: framing effects in narrative visualization.

    Science.gov (United States)

    Hullman, Jessica; Diakopoulos, Nicholas

    2011-12-01

    Narrative visualizations combine conventions of communicative and exploratory information visualization to convey an intended story. We demonstrate visualization rhetoric as an analytical framework for understanding how design techniques that prioritize particular interpretations in visualizations that "tell a story" can significantly affect end-user interpretation. We draw a parallel between narrative visualization interpretation and evidence from framing studies in political messaging, decision-making, and literary studies. Devices for understanding the rhetorical nature of narrative information visualizations are presented, informed by the rigorous application of concepts from critical theory, semiotics, journalism, and political theory. We draw attention to how design tactics represent additions or omissions of information at various levels-the data, visual representation, textual annotations, and interactivity-and how visualizations denote and connote phenomena with reference to unstated viewing conventions and codes. Classes of rhetorical techniques identified via a systematic analysis of recent narrative visualizations are presented, and characterized according to their rhetorical contribution to the visualization. We describe how designers and researchers can benefit from the potentially positive aspects of visualization rhetoric in designing engaging, layered narrative visualizations and how our framework can shed light on how a visualization design prioritizes specific interpretations. We identify areas where future inquiry into visualization rhetoric can improve understanding of visualization interpretation.

  4. Dorsal anterior cingulate cortex in typically developing children: Laterality analysis.

    Science.gov (United States)

    Wang, Jue; Yang, Ning; Liao, Wei; Zhang, Han; Yan, Chao-Gan; Zang, Yu-Feng; Zuo, Xi-Nian

    2015-10-01

    We aimed to elucidate the dACC laterality in typically developing children and their sex/age-related differences with a sample of 84 right-handed children (6-16 years, 42 boys). We first replicated the previous finding observed in adults that gray matter density asymmetry in the dACC was region-specific: leftward (left > right) in its superior part, rightward (left lateral temporal cortex) was more involved in the left hemisphere. In contrast, the inferior dACC connectivity with the default network (anterior medial prefrontal cortex) was more lateralized towards the right hemisphere. The superior dACC connectivity with lateral visual cortex was more distinct across two hemispheres in girls than that in boys. This connection in boys changed with age from right-prominent to left-prominent asymmetry whereas girls developed the connection from left-prominent to no asymmetry. These findings not only highlight the complexity and laterality of the dACC but also provided insights into dynamical structure-function relationships during the development.

  5. Anterior ischemic optic neuropathy in association with optic nervehead drusen

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    Bharathi Megur

    2014-01-01

    Full Text Available Optic nerve head drusen (ONHD are incidental ophthalmologic finding in the optic nerve. Patients with ONHD are often asymptomatic, but sometimes present with transient visual obscuration′s (TVO, the reported incidence of which is 8.6%. Optic nerve head drusen are of two types: Superficial; visible and deep. The deep-buried drusen mimic papilledema. Because of the varied presentation deep-buried drusen pose a diagnostic challenge to the ophthalmologists. In young patients, they are mistaken for papilledema as it is clinically difficult to detect a buried drusen in the optic nerve head, but are seen on the surface with aging as the retinal nerve fiber layer thins out. They are observed as pale yellow lesions more often located towards the poles. Clinical examination aided with diagnostic tests like computed tomography (CT orbits and ultrasound B scan can help establish the diagnosis. Herein, we report a rare case of optic nerve head drusen in a young lady, who presented with loss of vision and clinical evaluation and investigations suggested ONHD with anterior ischemic optic neuropathy.

  6. Pleasant human touch is represented in pregenual anterior cingulate cortex.

    Science.gov (United States)

    Lindgren, Lenita; Westling, Göran; Brulin, Christine; Lehtipalo, Stefan; Andersson, Micael; Nyberg, Lars

    2012-02-15

    Touch massage (TM) is a form of pleasant touch stimulation used as treatment in clinical settings and found to improve well-being and decrease anxiety, stress, and pain. Emotional responses reported during and after TM have been studied, but the underlying mechanisms are still largely unexplored. In this study, we used functional magnetic resonance (fMRI) to test the hypothesis that the combination of human touch (i.e. skin-to-skin contact) with movement is eliciting a specific response in brain areas coding for pleasant sensations. The design included four different touch conditions; human touch with or without movement and rubber glove with or without movement. Force (2.5 N) and velocity (1.5 cm/s) were held constant across conditions. The pleasantness of the four different touch stimulations was rated on a visual analog scale (VAS-scale) and human touch was rated as most pleasant, particularly in combination with movement. The fMRI results revealed that TM stimulation most strongly activated the pregenual anterior cingulate cortex (pgACC). These results are consistent with findings showing pgACC activation during various rewarding pleasant stimulations. This area is also known to be activated by both opioid analgesia and placebo. Together with these prior results, our finding furthers the understanding of the basis for positive TM treatment effects.

  7. Combinatorial semantics strengthens angular-anterior temporal coupling.

    Science.gov (United States)

    Molinaro, Nicola; Paz-Alonso, Pedro M; Duñabeitia, Jon Andoni; Carreiras, Manuel

    2015-04-01

    The human semantic combinatorial system allows us to create a wide number of new meanings from a finite number of existing representations. The present study investigates the neural dynamics underlying the semantic processing of different conceptual constructions based on predictions from previous neuroanatomical models of the semantic processing network. In two experiments, participants read sentences for comprehension containing noun-adjective pairs in three different conditions: prototypical (Redundant), nonsense (Anomalous) and low-typical but composable (Contrastive). In Experiment 1 we examined the processing costs associated to reading these sentences and found a processing dissociation between Anomalous and Contrastive word pairs, compared to prototypical (Redundant) stimuli. In Experiment 2, functional connectivity results showed strong co-activation across conditions between inferior frontal gyrus (IFG) and posterior middle temporal gyrus (MTG), as well as between these two regions and middle frontal gyrus (MFG), anterior temporal cortex (ATC) and fusiform gyrus (FG), consistent with previous neuroanatomical models. Importantly, processing of low-typical (but composable) meanings relative to prototypical and anomalous constructions was associated with a stronger positive coupling between ATC and angular gyrus (AG). Our results underscore the critical role of IFG-MTG co-activation during semantic processing and how other relevant nodes within the semantic processing network come into play to handle visual-orthographic information, to maintain multiple lexical-semantic representations in working memory and to combine existing representations while creatively constructing meaning.

  8. Complications of anterior cruciate ligament reconstruction: MR imaging.

    Science.gov (United States)

    Papakonstantinou, Olympia; Chung, Christine B; Chanchairujira, Kullanuch; Resnick, Donald L

    2003-05-01

    Arthroscopic reconstruction of the anterior cruciate ligament (ACL) using autografts or allografts is being performed with increasing frequency, particularly in young athletes. Although the procedure is generally well tolerated, with good success rates, early and late complications have been documented. As clinical manifestations of graft complications are often non-specific and plain radiographs cannot directly visualize the graft and the adjacent soft tissues, MR imaging has a definite role in the diagnosis of complications after ACL reconstruction and may direct subsequent therapeutic management. Our purpose is to review the normal MR imaging of the ACL graft and present the MR imaging findings of a wide spectrum of complications after ACL reconstruction, such as graft impingement, graft rupture, cystic degeneration of the graft, postoperative infection of the knee, diffuse and localized (i.e., cyclops lesion) arthrofibrosis, and associated donor site abnormalities. Awareness of the MR imaging findings of complications as well as the normal appearances of the normal ACL graft is essential for correct interpretation.

  9. Preoperative cryotherapy use in anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Koyonos, Loukas; Owsley, Kevin; Vollmer, Emily; Limpisvasti, Orr; Gambardella, Ralph

    2014-12-01

    Unrelieved postoperative pain may impair rehabilitation, compromise functional outcomes, and lead to patient dissatisfaction. Preemptive multimodal analgesic techniques may improve outcomes after surgery. We hypothesized that patients using preoperative cryotherapy plus a standardized postoperative treatment plan will have lower pain scores and require less pain medication compared with patients receiving a standardized postoperative treatment plan alone after arthroscopically assisted anterior cruciate ligament reconstruction (ACLR). A total of 53 consecutive patients undergoing arthroscopically assisted ACLR performed by one of seven surgeons were randomly assigned to one of two groups. Group 1 received no preoperative cryotherapy and group 2 received 30 to 90 minutes of preoperative cryotherapy to the operative leg using a commercial noncompressive cryotherapy unit. Visual analog scale pain scores and narcotic use were recorded for the first 4 days postoperatively. Total hours of cold therapy and continuous passive motion (CPM) use and highest degree of flexion achieved were recorded as well. Group 1 consisted of 26 patients (15 allograft Achilles tendon and 11 autograft bone patellar tendon bone [BPTB]), and group 2 consisted of 27 patients (16 allograft Achilles tendon and 11 autograft BPTB). Group 2 patients reported less pain (average 1.3 units, p cryotherapy, hours of CPM use, or maximum knee flexion achieved. Complications did not occur in either group. This is the first report we are aware of showing the postoperative effects of preoperative cryotherapy. Our results support the safety and efficacy of preoperative cryotherapy in a multimodal pain regimen for patients undergoing ACL reconstruction.

  10. Complications of anterior cruciate ligament reconstruction: MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Papakonstantinou, Olympia; Chung, Christine B.; Chanchairujira, Kullanuch; Resnick, Donald L. [Department of Radiology, Veterans Affairs Medical Center, University of California, 3350 La Jolla Village Dr., San Diego, CA 92161 (United States)

    2003-05-01

    Arthroscopic reconstruction of the anterior cruciate ligament (ACL) using autografts or allografts is being performed with increasing frequency, particularly in young athletes. Although the procedure is generally well tolerated, with good success rates, early and late complications have been documented. As clinical manifestations of graft complications are often non-specific and plain radiographs cannot directly visualize the graft and the adjacent soft tissues, MR imaging has a definite role in the diagnosis of complications after ACL reconstruction and may direct subsequent therapeutic management. Our purpose is to review the normal MR imaging of the ACL graft and present the MR imaging findings of a wide spectrum of complications after ACL reconstruction, such as graft impingement, graft rupture, cystic degeneration of the graft, postoperative infection of the knee, diffuse and localized (i.e., cyclops lesion) arthrofibrosis, and associated donor site abnormalities. Awareness of the MR imaging findings of complications as well as the normal appearances of the normal ACL graft is essential for correct interpretation. (orig.)

  11. MRI appearances of the anterior fibulocalcaneus muscle: a rare anterior compartment muscle

    Energy Technology Data Exchange (ETDEWEB)

    Upadhyay, Bhavin [Basildon and Thurrock University Hospitals NHS Foundation Trust, Imaging Department, Essex (United Kingdom); Amiras, Dimitri [Imperial College Health Care NHS Trust, Imaging Department, London (United Kingdom)

    2015-05-01

    MRI of a 62-year-old female presenting with ankle pain demonstrated an accessory muscle within the anterior compartment of the lower leg. The muscle originated from the fibula and anterior crural septum. The tendon passed anterior to the lateral malleolus and inserted at the critical angle of Gissane on the calcaneus. This muscle was initially described in the anatomic literature by Lambert and Atsas in 2010. To our knowledge, this is the first time the MRI appearances of this muscle has been described in the radiological literature. Awareness of the fibulocalcaneal muscle is important as it may represent a cause of ankle pain. In addition, the tendon could potentially be harvested for use in reconstructive procedures. (orig.)

  12. Evaluation of anterior ocular segment complications in patients with allergic keratoconjunctivitis

    OpenAIRE

    Patrícia Bezerra de Menezes Botelho; Patrícia Marback; Luciene Barbosa de Sousa; Mauro Campos; Luiz Antonio Vieira

    2003-01-01

    INTRODUÇÃO: A alergia ocular é condição que pode ocasionar sintomas de coceira, ardor e lacrimejamento, podendo também ser ameaçadora para visão. A fisiopatologia envolve mecanismos de hipersensibilidade imunológica. Devido a fatores imunológicos, o segmento anterior destes pacientes está mais suscetível a alterações que ameaçam a acuidade visual, tais como: opacidades corneanas, ceratocone e catarata. MÉTODOS: Foram revistos, retrospectivamente, 186 pacientes com ceratoconjuntivite alérgica ...

  13. Ceratoconjuntivite alérgica e complicações no segmento ocular anterior de pacientes

    OpenAIRE

    Botelho,Patrícia Bezerra de Menezes; Marback, Patrícia [UNIFESP; Sousa, Luciene Barbosa de [UNIFESP; Campos,Mauro; Vieira,Luiz Antonio

    2003-01-01

    INTRODUÇÃO: A alergia ocular é condição que pode ocasionar sintomas de coceira, ardor e lacrimejamento, podendo também ser ameaçadora para visão. A fisiopatologia envolve mecanismos de hipersensibilidade imunológica. Devido a fatores imunológicos, o segmento anterior destes pacientes está mais suscetível a alterações que ameaçam a acuidade visual, tais como: opacidades corneanas, ceratocone e catarata. MÉTODOS: Foram revistos, retrospectivamente, 186 pacientes com ceratoconjuntivite alérgica ...

  14. Treatment Approach to Small Inadvertent Injury of the Crystalline Lens Anterior Capsule During Iridodialysis Repair Surgery

    Directory of Open Access Journals (Sweden)

    Gökçen Gökçe

    2013-01-01

    Full Text Available A 22-year-old man presented to our ophthalmology department with photophobia. On ophthalmic examination, iridodialysis secondary to blunt trauma that occurred 5 years ago was diagnosed. During iridodialysis repair surgery, long curved double-armed needle of 10-0 polypropylene suture (PC-9 inserted into the 19 gauge side port turned down inadvertently by its own weight, resulting in crystalline lens anterior capsule perforation. Postoperative clinical observation revealed no lens opacification affecting visual acuity. This case report showed that lens aspiration surgery should be postponed if the capsule injury is small.(Turk J Ophthalmol 2013; 43: 61-3

  15. Toxic anterior-segment syndrome (TASS

    Directory of Open Access Journals (Sweden)

    Cetinkaya S

    2014-10-01

    Full Text Available Servet Cetinkaya,1 Zeynep Dadaci,2 Hüsamettin Aksoy,3 Nursen Oncel Acir,2 Halil Ibrahim Yener,4 Ekrem Kadioglu5 1Ophthalmology Clinics, Turkish Red Crescent Hospital, Konya, 2Department of Ophthalmology, Faculty of Medicine, Mevlana University, Konya, 3Ophthalmology Clinics, Karaman State Hospital, Karaman, 4Konya Eye Center Hospital, Konya, 5Ophthalmology Clinics, Beyhekim State Hospital, Konya, Turkey Purpose: To evaluate the clinical findings and courses of five patients who developed toxic anterior-segment syndrome (TASS after cataract surgery and investigate the cause.Materials and methods: In May 2010, on the same day, ten patients were operated on by the same surgeon. Five of these patients developed TASS postoperatively.Results: Patients had blurred-vision complaints on the first day after the operation, but no pain. They had different degrees of diffuse corneal edema, anterior-chamber reaction, fibrin, hypopyon, iris atrophies, and dilated pupils. Their vision decreased significantly, and their intraocular pressures increased. Both anti-inflammatory and antiglaucomatous therapies were commenced. Corneal edema and inflammation resolved in three cases; however, penetrating keratoplasty was needed for two cases and additional trabeculectomy was needed for one case. Although full investigations were undertaken at all steps, we could not find the causative agent.Conclusion: TASS is a preventable complication of anterior-segment surgery. Recognition of TASS, differentiating it from endophthalmitis, and starting treatment immediately is important. Controlling all steps in surgery, cleaning and sterilization of the instruments, and training nurses and other operation teams will help us in the prevention of TASS. Keywords: cataract, phacoemulsification, TASS, corneal edema, inflammation

  16. Infections after reconstructions of anterior cruciate ligament

    Directory of Open Access Journals (Sweden)

    Ristić Vladimir

    2014-01-01

    Full Text Available Introduction. Infections after anterior cruciate ligament reconstructions are rare, but, on the other hand, they are difficult to be treated. The aim of this study was to analyze causes of infections, risk factors, diagnostics, and possibilities of their prevention. Material and Methods. Seventeen deep infections (1.2% were found in 1425 patients who had undergone anterior cruciate ligament reconstructions. Fifteen patients were males and two were females. Out of 475 professional athletes nine (1.9% had this postoperative complication. Eleven patients with septic arthritis were allergic to penicillin. Three of them had immunosuppressive diseases. Results. Staphylococcus aureus was isolated in eleven cases (65%, other Staphylococcus and Streptococcus groups were found in four and three patients, respectively; while one patient had infection although the punctate was negative. Out of 965 patients with the patellar tendon grafts, ten (1.03% had this complication, while the incidence was 1.52% (7/460 in those with the hamstring grafts. Fifteen infections were acute with obvious symptoms within 14 days after surgery. Severe pain, limited range of motion, swelling of the knee joint and fever were the most common symptoms, while rubor and pus developed rarely. The infection was three times more frequent in the patients who had undergone surgery lasting more than 1.5 hour. Discussion and Conclusion. The following population groups are at risk of developing septic arthritis after anterior cruciate ligament reconstructions: professional athletes, those who are allergic to penicillin, and those with immunosuppressive diseases. Staphyllococus aureus is the most common cause of infection. The patients with the hamstring autografts have a higher risk than those with the patellar tendon grafts. Preventive measures that should be performed include aseptic conditions in operative rooms, irrigation of the graft before its placement into the bone tunnels

  17. The Anterior Cingulate Cortex and Pain Processing

    Directory of Open Access Journals (Sweden)

    Perry Neil Fuchs

    2014-05-01

    Full Text Available The neural network that contributes to the suffering which accompanies persistent pain states involves a number of brain regions. Of primary interest is the contribution of the cingulate cortex in processing the affective component of pain. The purpose of this review is to summarize recent data obtained using novel behavioral paradigms in animals based on measuring escape and/or avoidance of a noxious stimulus. These paradigms have successfully been used to study the nature of the neuroanatomical and neurochemical contributions of the anterior cingulate cortex to higher order pain processing in rodents.

  18. Biological fixation in anterior cruciate ligament surgery

    Directory of Open Access Journals (Sweden)

    Chih-Hwa Chen

    2014-04-01

    Full Text Available Successful anterior cruciate ligament (ACL reconstruction with tendon graft requires extensive tendon-to-bone healing in the bone tunnels and progressive graft ligamentization for biological, structural, and functional recovery of the ACL. Improvement in graft-to-bone healing is crucial for facilitating early, aggressive rehabilitation after surgery to ensure an early return to pre-injury activity levels. The use of various biomaterials for enhancing the healing of tendon grafts in bone tunnels has been developed. With the biological enhancement of tendon-to-bone healing, biological fixation of the tendon graft in the tunnel can be achieved in ACL reconstruction.

  19. Tunnel widening in anterior cruciate ligament reconstruction

    DEFF Research Database (Denmark)

    Clatworthy, M G; Annear, P; Bulow, J U

    1999-01-01

    .1% in the patella tendon group (P = film measurements. Tunnel widening did not correlate with the clinical findings, knee scores, KT-1000 or isokinetic muscle strength. Tunnel widening is marked in the hamstring group. Tunnel widening does not correlate with instability......We report a prospective series evaluating the incidence and degree of tunnel widening in a well-matched series of patients receiving a hamstring or patella tendon graft for anterior cruciate ligament (ACL) deficiency. We correlated tunnel widening with clinical factors, knee scores, KT-1000...

  20. [LAPAROSCOPIC ANTERIOR UTERINE LIGAMENTOPEXY--OUR EXPERIENCE].

    Science.gov (United States)

    Blagovest, Bechev; Magunska, Nadya; Kovachev, Emil; Ivanov, Stefan

    2015-01-01

    A great number operative techniques for correction of retroverted uterus are reported in the last years. The aim of these different methods is correction of the retroversion of the uterus, which is connected with pelvic congestion and symptomatic relief. We present a clinical case of 26 years old patient with one Caesarean section. The lady complains of chronic pelvic pain, dispareunia and dismenorrhea. The US exam shows an uterus in strong retroversion position. We restored the anatomic position of the uterus using laparoscopic anterior ligementopexy.

  1. Designing pathways

    DEFF Research Database (Denmark)

    Scheuer, John Damm

    2010-01-01

    The theoretical background in this chapter is organizational studies and especially theories about design and design processes in organizations. The concept of design is defined as a particular kind of work aimed at making arrangements in order to change existing situations into desired ones....... The illustrative case example is the introduction of clinical pathways in a psychiatric department. The contribution to a general core of design research is the development of the concept of design work and a critical discussion of the role of technological rules in design work....

  2. Surgical treatment and histopathology of a symptomatic free-floating primary pigment epithelial iris cyst in the anterior vitreous

    Directory of Open Access Journals (Sweden)

    Eman Al-Kahtani

    2011-01-01

    Full Text Available We report the surgical removal of an iris pigment epithelial cyst that was floating freely in the posterior chamber of an 18-month-old child. The reason for surgical removal was disturbance in near vision secondary to the movement of the cyst across the visual axis. Visual disturbance secondary to a unilateral anterior vitreous iris cyst at this age is a rare presentation and, to the best of our knowledge, has not been reported previously as an indication for surgery. We performed histopathological study of the cyst aspirate to determine its contents and its possible origin.

  3. Bilateral simultaneous anterior ischemic optic neuropathy, an extrahepatic manifestation of hepatitis C cured with direct acting antivirals

    Directory of Open Access Journals (Sweden)

    Prud’homme, Sylvie

    2016-04-01

    Full Text Available We report a patient with a bilateral optic anterior ischemic neuropathy as an extrahepatic complication of a chronic hepatitis C (HCV infection. The patient presented with a bilateral visual acuity loss and bilateral optic disc oedema. The optic neuropathy was associated with a sudden increase in the viral HCV load after a recent liver transplantation. The stop of the calcineurin inhibitor had no effect on the course of the optic neuropathy. Visual improvement and normalization of HCV viraemia occurred after treatment with sofosbuvir and daclatasvir, which are direct acting antivirals.

  4. Why Teach Visual Culture?

    Science.gov (United States)

    Passmore, Kaye

    2007-01-01

    Visual culture is a hot topic in art education right now as some teachers are dedicated to teaching it and others are adamant that it has no place in a traditional art class. Visual culture, the author asserts, can include just about anything that is visually represented. Although people often think of visual culture as contemporary visuals such…

  5. Defining the anterior nucleus of the thalamus (ANT as a deep brain stimulation target in refractory epilepsy: Delineation using 3 T MRI and intraoperative microelectrode recording

    Directory of Open Access Journals (Sweden)

    T. Möttönen

    2015-01-01

    Conclusions: ANT is delineated in 3 T MRI by visualization of a thin white matter lamina between ANT and other nuclear groups that lack spiking activity. Direct targeting in the anterior thalamic area is superior to indirect targeting due to extensive individual variation in the location of ANT. Without detailed imaging information, however, a single trajectory MER has little localizing value.

  6. The role of human ventral visual cortex in motion perception.

    Science.gov (United States)

    Gilaie-Dotan, Sharon; Saygin, Ayse P; Lorenzi, Lauren J; Egan, Ryan; Rees, Geraint; Behrmann, Marlene

    2013-09-01

    Visual motion perception is fundamental to many aspects of visual perception. Visual motion perception has long been associated with the dorsal (parietal) pathway and the involvement of the ventral 'form' (temporal) visual pathway has not been considered critical for normal motion perception. Here, we evaluated this view by examining whether circumscribed damage to ventral visual cortex impaired motion perception. The perception of motion in basic, non-form tasks (motion coherence and motion detection) and complex structure-from-motion, for a wide range of motion speeds, all centrally displayed, was assessed in five patients with a circumscribed lesion to either the right or left ventral visual pathway. Patients with a right, but not with a left, ventral visual lesion displayed widespread impairments in central motion perception even for non-form motion, for both slow and for fast speeds, and this held true independent of the integrity of areas MT/V5, V3A or parietal regions. In contrast with the traditional view in which only the dorsal visual stream is critical for motion perception, these novel findings implicate a more distributed circuit in which the integrity of the right ventral visual pathway is also necessary even for the perception of non-form motion.

  7. Mechanism of Action of Secreted Newt Anterior Gradient Protein

    Science.gov (United States)

    Grassme, Kathrin S.; Garza-Garcia, Acely; Delgado, Jean-Paul; Godwin, James W.; Kumar, Anoop; Gates, Phillip B.; Brockes, Jeremy P.

    2016-01-01

    Anterior gradient (AG) proteins have a thioredoxin fold and are targeted to the secretory pathway where they may act in the ER, as well as after secretion into the extracellular space. A newt member of the family (nAG) was previously identified as interacting with the GPI-anchored salamander-specific three-finger protein called Prod1. Expression of nAG has been implicated in the nerve dependence of limb regeneration in salamanders, and nAG acted as a growth factor for cultured newt limb blastemal (progenitor) cells, but the mechanism of action was not understood. Here we show that addition of a peptide antibody to Prod1 specifically inhibit the proliferation of blastema cells, suggesting that Prod1 acts as a cell surface receptor for secreted nAG, leading to S phase entry. Mutation of the single cysteine residue in the canonical active site of nAG to alanine or serine leads to protein degradation, but addition of residues at the C terminus stabilises the secreted protein. The mutation of the cysteine residue led to no detectable activity on S phase entry in cultured newt limb blastemal cells. In addition, our phylogenetic analyses have identified a new Caudata AG protein called AG4. A comparison of the AG proteins in a cell culture assay indicates that nAG secretion is significantly higher than AGR2 or AG4, suggesting that this property may vary in different members of the family. PMID:27100463

  8. How Visual Is the Visual Cortex? Comparing Connectional and Functional Fingerprints between Congenitally Blind and Sighted Individuals.

    Science.gov (United States)

    Wang, Xiaoying; Peelen, Marius V; Han, Zaizhu; He, Chenxi; Caramazza, Alfonso; Bi, Yanchao

    2015-09-09

    Classical animal visual deprivation studies and human neuroimaging studies have shown that visual experience plays a critical role in shaping the functionality and connectivity of the visual cortex. Interestingly, recent studies have additionally reported circumscribed regions in the visual cortex in which functional selectivity was remarkably similar in individuals with and without visual experience. Here, by directly comparing resting-state and task-based fMRI data in congenitally blind and sighted human subjects, we obtained large-scale continuous maps of the degree to which connectional and functional "fingerprints" of ventral visual cortex depend on visual experience. We found a close agreement between connectional and functional maps, pointing to a strong interdependence of connectivity and function. Visual experience (or the absence thereof) had a pronounced effect on the resting-state connectivity and functional response profile of occipital cortex and the posterior lateral fusiform gyrus. By contrast, connectional and functional fingerprints in the anterior medial and posterior lateral parts of the ventral visual cortex were statistically indistinguishable between blind and sighted individuals. These results provide a large-scale mapping of the influence of visual experience on the development of both functional and connectivity properties of visual cortex, which serves as a basis for the formulation of new hypotheses regarding the functionality and plasticity of specific subregions. Significance statement: How is the functionality and connectivity of the visual cortex shaped by visual experience? By directly comparing resting-state and task-based fMRI data in congenitally blind and sighted subjects, we obtained large-scale continuous maps of the degree to which connectional and functional "fingerprints" of ventral visual cortex depend on visual experience. In addition to revealing regions that are strongly dependent on visual experience (early visual

  9. Psychophysical evidence for impaired Magno, Parvo, and Konio-cellular pathways in dyslexic children

    Directory of Open Access Journals (Sweden)

    Khazar Ahmadi

    2015-01-01

    Conclusion: We may suggest that dyslexic subjects might suffer from both magnocellular and parvocellular deficits. Moreover, our results show partial impairment of the koniocellular pathway. Thus, dyslexia might be associated with deficits in all three visual pathways.

  10. Anterior segment spectral domain optical coherence tomography imaging of patients with anterior scleritis.

    Science.gov (United States)

    Levison, Ashleigh L; Lowder, Careen Y; Baynes, Kimberly M; Kaiser, Peter K; Srivastava, Sunil K

    2016-08-01

    The purpose of the study was to describe the findings seen on anterior segment spectral domain optical coherence tomography (SD-OCT) in patients with anterior scleritis and determine the feasibility of using SD-OCT to image and grade the degree of scleral inflammation and monitor response to treatment. All patients underwent slit lamp examination by a uveitis specialist, and the degree of scleral inflammation was recorded. Spectral domain OCT imaging was then performed of the conjunctiva and scleral tissue using a standardized acquisition protocol. The scans were graded and compared to clinical findings. Twenty-eight patients with anterior scleritis and ten patients without ocular disease were included in the study. Seventeen of the scleritis patients were followed longitudinally. Common findings on SD-OCT in patients with active scleritis included changes in hyporeflectivity within the sclera, nodules, and visible vessels within the sclera. There was significant variation in findings on SD-OCT within each clinical grade of active scleritis. These changes on SD-OCT improved with treatment and clinical improvement. SD-OCT imaging provided various objective measures that could be used in the future to grade inflammatory activity in patients with anterior scleritis. Longitudinal imaging of patients with active scleritis demonstrated that SD-OCT may have great utility in monitoring response to treatment.

  11. Accuracy of Lachman and Anterior Drawer Tests for Anterior Cruciate Ligament Injuries

    Directory of Open Access Journals (Sweden)

    Hadi Makhmalbaf

    2013-12-01

    Full Text Available   Background: The knee joint is prone to injury because of its complexity and weight-bearing function. Anterior cruciate ligament (ACL ruptures happen in young and physically active population and can result in instability, meniscal tears, and articular cartilage damage. The aim of this study is to evaluate the accuracy of Lachman and anterior drawer test in ACL injury in compare with arthroscopy.   Methods: In a descriptive, analytical study from 2009 to 2013, 653 patients who were suspected to ACL rapture were entered the study. Statistical analysis was performed by the usage of SPSS 19.0. Multiple comparison procedure was performed for comparing data between clinical examination and arthroscopic findings and their relation with age and sex. Results: Mean age of patients was 28.3±7.58 years (range from 16 to 68 years. From 428 patients, 41.2% (175 patients were between 26 and 35, 38.8% (165 ones between 15 and 25 and 20% (85 patients over 36 years. 414 patients were male (97.2% and 12 were female (2.8%. Sensitivity of anterior drawer test was 94.4% and sensitivity of Lachman test was 93.5%. Conclusion: The diagnosis and decision to reconstruct ACL injury can be reliably made regard to the anterior drawer and Lachman tests result. The tests did not have privilege to each other. These test accuracy increased considerably under anesthesia especially in women.

  12. Accuracy of Lachman and Anterior Drawer Tests for Anterior Cruciate Ligament Injuries

    Directory of Open Access Journals (Sweden)

    Hadi Makhmalbaf

    2013-12-01

    Full Text Available Background: The knee joint is prone to injury because of its complexity and weight-bearing function. Anterior cruciate ligament (ACL ruptures happen in young and physically active population and can result in instability, meniscal tears, and articular cartilage damage. The aim of this study is to evaluate the accuracy of Lachman and anterior drawer test in ACL injury in compare with arthroscopy.   Methods: In a descriptive, analytical study from 2009 to 2013, 653 patients who were suspected to ACL rapture were entered the study. Statistical analysis was performed by the usage of SPSS 19.0. Multiple comparison procedure was performed for comparing data between clinical examination and arthroscopic findings and their relation with age and sex. Results: Mean age of patients was 28.3±7.58 years (range from 16 to 68 years. From 428 patients, 41.2% (175 patients were between 26 and 35, 38.8% (165 ones between 15 and 25 and 20% (85 patients over 36 years. 414 patients were male (97.2% and 12 were female (2.8%. Sensitivity of anterior drawer test was 94.4% and sensitivity of Lachman test was 93.5%. Conclusion: The diagnosis and decision to reconstruct ACL injury can be reliably made regard to the anterior drawer and Lachman tests result. The tests did not have privilege to each other. These test accuracy increased considerably under anesthesia especially in women.

  13. The normal anterior cruciate ligament as a model for tensioning strategies in anterior cruciate ligament grafts

    NARCIS (Netherlands)

    Arnold, MP; Verdonschot, N; van Kampen, A

    2005-01-01

    Background: There is some confusion about the relationship between the tension placed on the graft and the joint position used in the fixation of anterior cruciate ligament grafts. This is because of deficiency in accurate basic science about this important interaction in the normal and reconstructe

  14. The normal anterior cruciate ligament as a model for tensioning strategies in anterior cruciate ligament grafts.

    NARCIS (Netherlands)

    Arnold, M.P.; Verdonschot, N.J.J.; Kampen, A. van

    2005-01-01

    BACKGROUND: There is some confusion about the relationship between the tension placed on the graft and the joint position used in the fixation of anterior cruciate ligament grafts. This is because of deficiency in accurate basic science about this important interaction in the normal and reconstructe

  15. Anterior cutaneous nerve entrapment syndrome: management challenges

    Directory of Open Access Journals (Sweden)

    Chrona E

    2017-01-01

    Full Text Available Eleni Chrona,1,2 Georgia Kostopanagiotou,1 Dimitrios Damigos,3 Chrysanthi Batistaki1 1Second Department of Anesthesiology, School of Medicine, National and Kapodistrian University of Athens, “Attikon” Hospital, Athens, 2Department of Anesthesiology, General Hospital of “Ag. Panteleimon,” Piraeus, 3Department of Medical Psychology, Medical School of Ioannina, University of Ioannina, Ioannina, Greece Abstract: Anterior cutaneous nerve entrapment syndrome (ACNES is a commonly underdiagnosed and undertreated chronic state of pain. This syndrome is characterized by the entrapment of the cutaneous branches of the lower thoracoabdominal intercostal nerves at the lateral border of the rectus abdominis muscle, which causes severe, often refractory, chronic pain. This narrative review aims to identify the possible therapeutic strategies for the management of the syndrome. Seventeen studies about ACNES therapy were reviewed; of them, 15 were case–control studies, case series, or case reports, and two were randomized controlled trials. The presently available management strategies for ACNES include trigger point injections (diagnostic and therapeutic, ultrasound-guided blocks, chemical neurolysis, and surgical ­neurectomy, in combination with systemic medication, as well as some emerging techniques, such as radiofrequency ablation and neuromodulation. An increased awareness of the syndrome and the use of specific diagnostic criteria for its recognition are required to facilitate an early and successful management. This review compiles the proposed ­management strategies for ACNES. Keywords: anterior cutaneous nerve entrapment syndrome, intercostal, neuralgia, management

  16. Adjacent Segment Pathology after Anterior Cervical Fusion.

    Science.gov (United States)

    Chung, Jae Yoon; Park, Jong-Beom; Seo, Hyoung-Yeon; Kim, Sung Kyu

    2016-06-01

    Anterior cervical fusion has become a standard of care for numerous pathologic conditions of the cervical spine. However, subsequent development of clinically significant disc disease at levels adjacent to fused discs is a serious long-term complication of this procedure. As more patients live longer after surgery, it is foreseeable that adjacent segment pathology (ASP) will develop in increasing numbers of patients. Also, ASP has been studied more intensively with the recent popularity of motion preservation technologies like total disc arthroplasty. The true nature and scope of ASP remains poorly understood. The etiology of ASP is most likely multifactorial. Various factors including altered biomechanical stresses, surgical disruption of soft tissue and the natural history of cervical disc disease contribute to the development of ASP. General factors associated with disc degeneration including gender, age, smoking and sports may play a role in the development of ASP. Postoperative sagittal alignment and type of surgery are also considered potential causes of ASP. Therefore, a spine surgeon must be particularly careful to avoid unnecessary disruption of the musculoligamentous structures, reduced risk of direct injury to the disc during dissection and maintain a safe margin between the plate edge and adjacent vertebrae during anterior cervical fusion.

  17. MRI of anterior cruciate ligament autografts

    Energy Technology Data Exchange (ETDEWEB)

    Ogi, Shigeyuki; Ariizumi, Mitsuko; Yamagishi, Tsuneo [The Aoyama Tokyo Metropolitan office' s Hospital (Japan); Agata, Toshihiko; Tada, Shinpei; Fukuda, Kunihiko

    2000-09-01

    The purpose of this study was to assess the usefulness of MRI in the evaluation of autografts after anterior cruciate ligament reconstruction. The subjects were 110 patients with anterior cruciate ligament reconstruction using patellar tendon autografts who underwent clinical examination, MRI, and arthroscopy of the knee. T1- and T2-weighted MR images were obtained in sagittal plane. Clinical findings were categorized into three groups: normal, borderline, and abnormal. The MRI appearances of the autografts were categorized into three types: straight continuous band (type I), interrupted band (type II) and generalized increased intensity band (type III). The clinical findings and MRI findings were compared with arthroscopic findings. Ninety-six percent of the type I showed no autograft tear on arthroscopy. In comparison with the clinical findings, MRI was found to be well correlated with arthroscopic findings. In conclusion, if the clinical findings are normal, patients are to be followed-up without MRI and arthroscopy. However, if clinical findings are either borderline or abnormal, MRI should be performed prior to arthroscopy. (author)

  18. Penghentian Karies Gigi Sulung Anterior (Laporan Penelitian

    Directory of Open Access Journals (Sweden)

    Titi Pratiwi Indra Yoga

    2015-10-01

    Full Text Available Salah satu cara menanggulangi karies pada gigi sulung anterior adalah dengan mengasah gigi menjadi bentuk self cleansing atau tapered dan kemudian mengolesnya dengan larutan SnF2 10%. Cara ini relatif mudah mengerjakannya serta murah biayanya. Keburukannya hanya pada masalah estetis, yaitu bentuk gigi menjadi lebih kecil, serta adanya staining kecoklatan karena pengendapan Sn. Penelitian ini dilakukan untuk mengetahui apakah cara ini dapat menghentikan karies pada gigi sulung anterior, serta sampai berapa lama pengaruh SnF2 10% dapat menghentikan karies. Sampel diambil dari murid TK yang berusia 2,5 sampai 5 tahun, gigi sulung anteriornya terkena karies email pada bagian proksimal satu atau dua sisi. Mengingat usia sampel yang masih muda, maka sampai akhir penelitian hanya didapat 20 orang anak yang memenuhi kriteria, dan hasil penelitian dihitung secara statistik dengan X2 – test. Hasil penelitian ternyata prosedur perawatan ini berhasil secara bermakna setelah 3-6 bulan (X2 = 0.056, df = 1, dan p < 0.05.

  19. Differential expression of Bmp2, Bmp4 and Bmp3 in embryonic development of mouse anterior and posterior palate

    Institute of Scientific and Technical Information of China (English)

    NIE Xu-guang

    2005-01-01

    Background The palate is differently regulated and developed along the anterior-posterior axis. The Bmp signal pathway plays a crucial role in palatogenesis. Conditioned-inactivation of Bmp type I receptor Alk2 or Alk3 in the neural crest or craniofacial region leads to palatal cleft in mice. However, how different Bmp members are involved in palatogenesis remains to be elucidated. In the present study, mRNA expression patterns of Bmp2, Bmp3 and Bmp4 in the developing anterior and posterior palates were examined and compared, focusing on the fusion stage. Methods To detect the expression of Bmp mRNA, antisense riboprobes were synthesized by in vitro transcription. Radioactive in situ hybridization was performed on sagital and coronal sections of mice head from E13 to E18. Results The expression of these Bmps were developmentally regulated in the anterior and posterior palates prior to, during and after palatal fusion. During palatal fusion, Bmp4 expression shifted from the anterior to the posterior palate, Bmp2 was highly expressed in both the anterior and posterior palates in this process, whereas Bmp3 was only localized in the posterior palate. They showed generally non-overlapping pattern in their expression domains. Thereafter, their expression was detected in both the anterior and posterior palates regulating osteogenesis and myogenesis respectively. Conclusions Bmp signalling is involved in palatogenesis in multiple stages and has multiple roles in regulating anterior and posterior palatal development. Disturbances of Bmp signalling during palatogenesis might be a possible mechanism of cleft palate.

  20. Action preparation shapes processing in early visual cortex.

    Science.gov (United States)

    Gutteling, Tjerk P; Petridou, Natalia; Dumoulin, Serge O; Harvey, Ben M; Aarnoutse, Erik J; Kenemans, J Leon; Neggers, Sebastian F W

    2015-04-22

    Preparation for an action, such as grasping an object, is accompanied by an enhanced perception of the object's action-relevant features, such as orientation and size. Cortical feedback from motor planning areas to early visual areas may drive this enhanced perception. To examine whether action preparation modulates activity in early human visual cortex, subjects grasped or pointed to oriented objects while high-resolution fMRI data were acquired. Using multivoxel pattern analysis techniques, we could decode with >70% accuracy whether a grasping or pointing action was prepared from signals in visual cortex as early as V1. These signals in early visual cortex were observed even when actions were only prepared but not executed. Anterior parietal cortex, on the other hand, showed clearest modulation for actual movements. This demonstrates that preparation of actions, even without execution, modulates relevant neuronal populations in early visual areas.

  1. Investigating visual analogies for visual insight problems

    OpenAIRE

    Corina Sas; Eric Luchian; Linden Ball

    2010-01-01

    Much research has focused on the impact of analogies in insight problem solving, but less work has investigated how the visual analogies for insight are actually constructed. Thus, it appears that in the search for their facilitative impact on the incubation effect, the understanding of what makes good visual analogies has somehow been lost. This paper presents preliminary work of constructing a set of 6 visual analogies and evaluating their impact on solving the visual problem of eight coins...

  2. Data Visualization and Infographics

    OpenAIRE

    Prepared by Mathematica Policy Research

    2014-01-01

    Data visualization translates complex ideas and concepts into a simple visual context. Patterns, trends, and relationships that might go undetected in text are conveyed at a glance in effective data visualization.

  3. Cortical Visual Impairment

    Science.gov (United States)

    ... Frequently Asked Questions Español Condiciones Chinese Conditions Cortical Visual Impairment En Español Read in Chinese What is cortical visual impairment? Cortical visual impairment (CVI) is a decreased ...

  4. Deep anterior lamellar keratoplasty for the management of iatrogenic keratectasia occurring after hexagonal keratotomy

    Directory of Open Access Journals (Sweden)

    Paras Mehta

    2012-01-01

    Full Text Available Iatrogenic keratectasia has been reported subsequent to refractive surgery or trauma. Hexagonal keratotomy (HK is a surgical incisional technique to correct hyperopia. A number of complications have been reported following this procedure, including irregular astigmatism, wound healing abnormalities and corneal ectasia. When visual acuity is poor because of ectasia or irregular astigmatism and contact lens fitting is not possible, penetrating or lamellar keratoplasty can be performed. Since incisions in refractive keratotomy are set at 90-95% depth of cornea, intraoperative microperforations are known to occur and lamellar keratoplasty may become difficult. We describe deep anterior lamellar keratoplasty (DALK used to successfully manage keratectasia after HK. Pre DALK vision was 20/400 and post DALK vision was 20/30 two months after surgery. This report aims to show improved visual outcome in corneal ectasia secondary to HK. DALK can be a procedure of choice with proper case selection.

  5. Role of anterior segment optical coherence tomogram in Descemet′s membrane detachment

    Directory of Open Access Journals (Sweden)

    Sonia Kothari

    2011-01-01

    Full Text Available Descemet′s membrane detachment (DD is a rare but serious complication of intraocular surgery. In rare cases where corneal edema is severe and we may not be able to visualize DD on slit-lamp examination, anterior segment optical coherence tomogram (AS-OCT would be helpful. We describe two patients with DD, highlighting the role of AS-OCT in early diagnosis and management of patients with DD. One of the patients had DD with rolled in edge, which could only be visualized with AS-OCT. In such a situation, AS-OCT can identify the edge of detachment and show the exact position of the rolled edge, which can allow us to plan the surgical strategy to unroll the DD.

  6. Topography and areal organization of mouse visual cortex.

    Science.gov (United States)

    Garrett, Marina E; Nauhaus, Ian; Marshel, James H; Callaway, Edward M

    2014-09-10

    To guide future experiments aimed at understanding the mouse visual system, it is essential that we have a solid handle on the global topography of visual cortical areas. Ideally, the method used to measure cortical topography is objective, robust, and simple enough to guide subsequent targeting of visual areas in each subject. We developed an automated method that uses retinotopic maps of mouse visual cortex obtained with intrinsic signal imaging (Schuett et al., 2002; Kalatsky and Stryker, 2003; Marshel et al., 2011) and applies an algorithm to automatically identify cortical regions that satisfy a set of quantifiable criteria for what constitutes a visual area. This approach facilitated detailed parcellation of mouse visual cortex, delineating nine known areas (primary visual cortex, lateromedial area, anterolateral area, rostrolateral area, anteromedial area, posteromedial area, laterointermediate area, posterior area, and postrhinal area), and revealing two additional areas that have not been previously described as visuotopically mapped in mice (laterolateral anterior area and medial area). Using the topographic maps and defined area boundaries from each animal, we characterized several features of map organization, including variability in area position, area size, visual field coverage, and cortical magnification. We demonstrate that higher areas in mice often have representations that are incomplete or biased toward particular regions of visual space, suggestive of specializations for processing specific types of information about the environment. This work provides a comprehensive description of mouse visuotopic organization and describes essential tools for accurate functional localization of visual areas.

  7. Electroretinography and Visual Evoked Potentials in Childhood Brain Tumor Survivors.

    Science.gov (United States)

    Pietilä, Sari; Lenko, Hanna L; Oja, Sakari; Koivisto, Anna-Maija; Pietilä, Timo; Mäkipernaa, Anne

    2016-07-01

    This population-based cross-sectional study evaluates the clinical value of electroretinography and visual evoked potentials in childhood brain tumor survivors. A flash electroretinography and a checkerboard reversal pattern visual evoked potential (or alternatively a flash visual evoked potential) were done for 51 survivors (age 3.8-28.7 years) after a mean follow-up time of 7.6 (1.5-15.1) years. Abnormal electroretinography was obtained in 1 case, bilaterally delayed abnormal visual evoked potentials in 22/51 (43%) cases. Nine of 25 patients with infratentorial tumor location, and altogether 12 out of 31 (39%) patients who did not have tumors involving the visual pathways, had abnormal visual evoked potentials. Abnormal electroretinographies are rarely observed, but abnormal visual evoked potentials are common even without evident anatomic lesions in the visual pathway. Bilateral changes suggest a general and possibly multifactorial toxic/adverse effect on the visual pathway. Electroretinography and visual evoked potential may have clinical and scientific value while evaluating long-term effects of childhood brain tumors and tumor treatment.

  8. Iris-claw intraocular lens implantation: Anterior chamber versus retropupillary implantation

    Science.gov (United States)

    Helvacı, Sezer; Demirdüzen, Selahaddin; Öksüz, Hüseyin

    2016-01-01

    Purpose: To compare the outcomes of anterior chamber and retropupillary implantation of iris-claw Artisan intraocular lenses (IOL). Design: Prospective, randomized, single-blinded study. Patients and Methods: Forty eyes of forty aphakic patients were enrolled. Patients were randomized into two groups. Each group includes twenty patients. Group 1 received anterior chamber Artisan IOL implantation. Group 2 received retropupillary Artisan IOL implantation. Preoperative and postoperative corrected distance visual acuity (CDVA), intraocular pressure (IOP), and all complications were noted and compared at 6 months follow-up. Results: Each two groups obtained a significant improvement in CDVA (P < 0.05). Four patients in Group 1 and five patients in Group 2 had significant but nonpermanent increase at IOP values. There were one and two pupillary irregularity in Group 1 and Group 2, respectively. In one patient, a shallow and inferior located retinal detachment were encountered in anterior chamber group. Conclusions: The results were not significantly different between the two fixation techniques for iris-claw lens. The surgery procedure is dependent to surgeon experience and eye's conditions. PMID:26953023

  9. A Rare Nasal Bone Fracture: Anterior Nasal Spine Fracture

    Directory of Open Access Journals (Sweden)

    Egemen Kucuk

    2014-04-01

    Full Text Available Anterior nasal spine fractures are a quite rare type of nasal bone fractures. Associated cervical spine injuries are more dangerous than the nasal bone fracture. A case of the anterior nasal spine fracture, in a 18-year-old male was presented. Fracture of the anterior nasal spine, should be considered in the differential diagnosis of the midface injuries and also accompanying cervical spine injury should not be ignored.

  10. Winging of scapula due to serratus anterior tear

    Institute of Scientific and Technical Information of China (English)

    Varun Kumar Singh; Gauresh Shantaram Vargaonkar

    2014-01-01

    Winging of scapula occurs most commonly due to injury to long thoracic nerve supplying serratus anterior muscle.Traumatic injury to serratus anterior muscle itself is very rare.We reported a case of traumatic winging of scapula due to tear of serratus anterior muscle in a 19-year-old male.Winging was present in neutral position and in extension of right shoulder joint but not on "push on wall" test.Patient was managed conservatively and achieved satisfactory result.

  11. Transanal stent in anterior resection does not prevent anastomotic leakage

    DEFF Research Database (Denmark)

    Bülow, Steffen; Bulut, O; Christensen, Ib Jarle;

    2006-01-01

    OBJECTIVE: A defunctioning transanal stent may theoretically reduce the leakage rate after anterior rectal resection. We present a randomized open study with the aim of comparing the leakage rate after anterior resection with a loop ileostomy, a transanal stent, both or neither. PATIENTS....... On this basis it was decided to discontinue the study prematurely for ethical reasons. CONCLUSION: Decompression of the anastomosis with a transanal stent does not reduce the risk of anastomotic leakage after anterior resection....

  12. Double anterior chamber in a patient with glaucoma and microspherophakia

    Directory of Open Access Journals (Sweden)

    Hamid Khakshoor

    2011-01-01

    Full Text Available We report the case of a 16-year-old woman with microspherophakia and secondary open angle glaucoma. The patient presented with a membrane dividing the anterior chamber into two segments without edema or Descemet′s membrane detachment. Slit lamp biomicroscopy, Pentacam, and specular microscopy images were obtained. Double anterior chamber is primarily found in patients with anterior chamber anomalies when there is no history of surgery or trauma.

  13. Early Diagnosis of Keratoconus with Orbscan- Ⅱ Anterior System

    Institute of Scientific and Technical Information of China (English)

    李新宇; 刘磊; 邱良秀

    2002-01-01

    Summary: Orbscan- Ⅱ anterior system was used for early diagnosis of keratoconus. 48 Eyes of 24patients with suspicious keratoconus were examined by Orbscan-Ⅱ anterior system from Dec.1999 to Dec. 2000 and followed up. The values of Diff and anterior chamber depth (ACD) wererecorded. Results indicated that values of Diff and ACD were increased in 4 eyes of 2 patients withkeratoconus trend during follow-up. Taking advantage of Orbscan- Ⅱ anterior system to observethe values of Diff and ACD can early diagnose the sub-clinical keratoconus. The values of Diff andACD can sensitively report the progression of keratoconus.

  14. Morphogenesis of the anterior segment in the zebrafish eye

    Directory of Open Access Journals (Sweden)

    Link Brian A

    2005-06-01

    Full Text Available Abstract Background The ocular anterior segment is critical for focusing incoming light onto the neural retina and for regulating intraocular pressure. It is comprised of the cornea, lens, iris, ciliary body, and highly specialized tissue at the iridocorneal angle. During development, cells from diverse embryonic lineages interact to form the anterior segment. Abnormal migration, proliferation, differentiation, or survival of these cells contribute to diseases of the anterior segment such as corneal dystrophy, lens cataract, and glaucoma. Zebrafish represent a powerful model organism for investigating the genetics and cell biology of development and disease. To lay the foundation for genetic studies of anterior segment development, we have described the morphogenesis of this structure in zebrafish. Results As in other vertebrates, the zebrafish anterior segment derives from diverse origins including surface ectoderm, periocular mesenchyme, and neuroepithelium. Similarly, the relative timing of tissue differentiation in the anterior segment is also conserved with other vertebrates. However, several morphogenic features of the zebrafish anterior segment differ with those of higher vertebrates. These include lens delamination as opposed to invagination, lack of iris muscles and ciliary folds, and altered organization in the iridocorneal angle. In addition, substantial dorsal-ventral differences exist within the zebrafish anterior segment. Conclusion Cumulatively, our anatomical findings provide a reference point to utilize zebrafish for genetic studies into the mechanisms of development and maintenance of the anterior segment.

  15. Winging of scapula due to serratus anterior tear

    Directory of Open Access Journals (Sweden)

    Varun Singh Kumar

    2014-10-01

    Full Text Available 【Abstract】Winging of scapula occurs most commonly due to injury to long thoracic nerve supplying serratus anterior muscle. Traumatic injury to serratus anterior muscle itself is very rare. We reported a case of traumatic winging of scapula due to tear of serratus anterior muscle in a 19-year-old male. Winging was present in neutral position and in extension of right shoulder joint but not on "push on wall" test. Patient was managed conservatively and achieved satisfactory result. Key words: Serratus anterior tear; Scapula; Wounds and injuries

  16. Visual acuity evaluated by pattern-reversal visual-evoked potential is affected by check size/visual angle

    Institute of Scientific and Technical Information of China (English)

    Xiping Chen; Qianqian Li; Xiaoqin Liu; Li Yang; Wentao Xia; Luyang Tao

    2012-01-01

    Objective To systemically explore the range of visual angles that affect visual acuity,and to establish the relationship between the P 1 component (peak latency ~100 ms) of the pattern-reversal visual-evoked potential (PRVEP) and the visual acuity at particular visual angles.Methods Two hundred and ten volunteers were divided into seven groups,according to visual acuity as assessed by the standard logarithmic visual acuity chart (SLD-II).For each group,the PRVEP components were elicited in response to visual angle presentations at 8°,4°,2°,1 °/60′,30′,15′,and 7.5′,in the whiteblack chess-board reversal mode with a contrast level of 100% at a frequency of 2 Hz.Visual stimuli were presented monocularly,and 200 presentations were averaged for each block of trials.The early and stable component P1 was recorded at the mid-line of the occipital region (Oz) and analyzed with SPSS 13.00.Results (1) Oz had the maximum P1 amplitude;there was no significant difference between genders or for interocular comparison in normal controls and subjects with optic myopia.(2) The P1 latency decreased slowly below 30′,then increased rapidly.The P1 amplitude initially increased with check size,and was maximal at ~1° and ~30′.(3) The P1 latency in the group with visual acuity ≤0.2 was significantly different at 8°,15′ and 7.5′,while the amplitude differed at all visual angles,compared with the group with normal vision.Diferences in P1 for the groups with 0.5 and 0.6 acuity were only present at visual angles <1°.(4) Regression analysis showed that the P 1 latency and amplitude were associated with visual acuity over the full range of visual angles.There was a moderate correlation at visual angles <30′.Regression equations were calculated for the P1 components and visual acuity,based on visual angle.Conclusion (1) Visual angle should be taken into consideration when exploring the function of the visual pathway,especially visual acuity.A visual angle

  17. Crossmodal enhancement of visual orientation discrimination by looming sounds requires functional activation of primary visual areas: a case study.

    Science.gov (United States)

    Cecere, Roberto; Romei, Vincenzo; Bertini, Caterina; Làdavas, Elisabetta

    2014-04-01

    Approaching or looming sounds are salient, potentially threatening stimuli with particular impact on visual processing. The early crossmodal effects by looming sounds (Romei, Murray, Cappe, & Thut, 2009) and their selective impact on visual orientation discrimination (Leo, Romei, Freeman, Ladavas, & Driver, 2011) suggest that these multisensory interactions may take place already within low-level visual cortices. To investigate this hypothesis, we tested a patient (SDV) with bilateral occipital lesion and spared residual portions of V1/V2. Accordingly, SDV׳s visual perimetry revealed blindness of the central visual field with some residual peripheral vision. In two experiments we tested for the influence of looming vs. receding and stationary sounds on SDV׳s line orientation discrimination (orientation discrimination experiment) and visual detection abilities (detection experiment) in the preserved or blind portions of the visual field, corresponding to spared and lesioned areas of V1, respectively. In the visual orientation discrimination experiment we found that SDV visual orientation sensitivity significantly improved for visual targets paired with looming sounds but only for lines presented in the partially preserved visual field. In the visual detection experiment, where SDV was required to simply detect the same stimuli presented in the orientation discrimination experiment, a generalised sound-induced visual improvement both in the intact and in blind portion of the visual field was observed. These results provide direct evidence that early visual areas are critically involved in crossmodal modulation of visual orientation sensitivity by looming sounds. Thus, a lesion in V1 prevents the enhancement of visual orientation sensitivity. In contrast, the same lesion does not prevent the visual detection enhancement by a sound, probably due to alternative visual pathways (e.g. retino-colliculo-extrastriate) which are usually spared in these patients and able to

  18. [Visual epileptic seizures. Signs and symptoms, and clinical implications].

    Science.gov (United States)

    González-Cuevas, Montserrat; Toledo, Manuel; Santamarina, Estevo; Sueiras-Gil, María; Cambrodí-Masip, Roser; Sarria, Silvana; Quintana, Manuel; Salas-Puig, Javier

    2015-03-16

    Introduccion. Los fenomenos visuales pueden ser sintomas de crisis epilepticas, aunque con un significado clinico y una relacion con el foco epileptogeno incierto. Objetivo. Describir las implicaciones clinicas de las crisis epilepticas visuales segun su semiologia en adultos. Pacientes y metodos. Durante un año se recoge consecutivamente a pacientes que describian semiologia visual como manifestacion principal de sus crisis y se clasifican los sintomas visuales segun las caracteristicas de la descripcion. Resultados. Se incluye a 78 pacientes con una edad media de 43,5 años. El 97% de los casos eran epilepsias focales. Entre el 63% de las epilepsias sintomaticas, el 57% eran vasculares. Las crisis visuales eran, en un 81,9%, el aura previa a la crisis, y en un 17,9%, crisis visuales aisladas. La coexistencia de crisis visuales y otro tipo de crisis se asocio a farmacorresistencia (p = 0,021). Los sintomas visuales fueron: alucinaciones simples (55,1%), ilusiones (23,1%), alucinaciones complejas (15,4%) y perdida de vision (6,4%). La localizacion lobar de las lesiones era occipital (24,4%), temporoparietooccipital (21,8%), temporal (9%), parietal (3,8%) y frontal (1,3%). Las lesiones occipitales se asociaron con alucinaciones visuales simples (p < 0,001), y las ilusiones visuales y alucinaciones visuales complejas, con lesiones de la encrucijada temporoparietooccipital (p < 0,05). Del 55,1% de los pacientes con lesion unilateral en la resonancia magnetica, el 33% referia los sintomas en el hemicampo visual contralateral. Conclusiones. Las crisis visuales se presentan, principalmente, como auras epilepticas. Las alucinaciones simples se relacionan con el origen occipital, mientras que las alucinaciones complejas se asocian con regiones cerebrales mas anteriores. La aparicion de fenomenos visuales lateralizados nos orienta a un origen en el hemisferio contralateral.

  19. The visual pulvinar in tree shrews II. Projections of four nuclei to areas of visual cortex.

    Science.gov (United States)

    Lyon, David C; Jain, Neeraj; Kaas, Jon H

    2003-12-22

    Patterns of thalamocortical connections were related to architectonically defined subdivisions of the pulvinar complex and the dorsolateral geniculate nucleus (LGN) in tree shrews (Tupaia belangeri). Tree shrews are of special interest because they are considered close relatives of primates, and they have a highly developed visual system. Several distinguishable tracers were injected within and across cortical visual areas in individual tree shrews in order to reveal retinotopic patterns and cortical targets of subdivisions of the pulvinar. The results indicate that each of the three architectonic regions of the pulvinar has a distinctive pattern of cortical connections and that one of these divisions is further divided into two regions with different patterns of connections. Two of the pulvinar nuclei have similar retinotopic patterns of projections to caudal visual cortex. The large central nucleus of the pulvinar (Pc) projects to the first and second visual areas, V1 and V2, and an adjoining temporal dorsal area (TD) in retinotopic patterns indicating that the upper visual quadrant is represented dorsal to the lower quadrant in Pc. The smaller ventral nucleus (Pv) which stains darkly for the Cat-301 antigen, projects to these same cortical areas, with a retinotopic pattern. Pv also projects to a temporal anterior area, TA. The dorsal nucleus (Pd), which densely expresses AChE, projects to posterior and ventral areas of temporal extrastriate cortex, areas TP and TPI. A posterior nucleus, Pp, projects to anterior areas TAL and TI, of the temporal lobe, as well as TPI. Injections in different cortical areas as much as 6 mm apart labeled overlapping zones in Pp and double-labeled some cells. These results indicate that the visual pulvinar of tree shrews contains at least four functionally distinct subdivisions, or nuclei. In addition, the cortical injections revealed that the LGN projects topographically and densely to V1 and that a significant number of LGN neurons

  20. Síndrome tóxica do segmento anterior Toxic anterior segment syndrome

    Directory of Open Access Journals (Sweden)

    Luiz Filipe de Albuquerque Alves

    2013-02-01

    Full Text Available A síndrome tóxica do segmento anterior (STSA é uma severa reação inflamatória aguda causada por agente não infeccioso que entra no segmento anterior, resultando em lesão celular tóxica com necrose e apoptose mediado por resposta imunológica. Neste relato de caso de STSA são enfatizadas as causas mais comuns para o aparecimento da síndrome, apontam para os cuidados que devem ser tomados no processo de esterilização do material cirúrgico além de revisar a melhor conduta diante desses casos. Em conclusão notou-se que o foco principal deve ser a prevenção, pois o tratamento busca apenas suprimir a resposta inflamatória secundária. O tratamento nos casos de STSA consiste em intensa instilação de esteróides tópicos com seguimento rigoroso e controle de complicações tardias como o glaucoma.Toxic anterior segment syndrome is acute inflammatory reaction caused by a noninfectious substance that enters the anterior segment, resulting in extracellular damage with necrosis and apoptosis during an immune response. We have the report of a case of toxic anterior segment syndrome (TASS, in which the authors seek to emphasize the most common causes of the appearance of these syndrome. They point out the care that must be taken in the process of sterilization of surgical material, in addition to reviewing the best conduct when faced with these cases. In conclusion, it was noted that the main focus should be on prevention, as treatment only seeks to suppress the secondary inflammatory response. Treatment in cases of toxic anterior segment syndrome (TASS consists of intense instillation of topical steroids with strict follow-up and control of late complications such as glaucoma.

  1. Neurologic complication after anterior sciatic nerve block.

    Science.gov (United States)

    Shah, Shruti; Hadzic, Admir; Vloka, Jerry D; Cafferty, Maureen S; Moucha, Calin S; Santos, Alan C

    2005-05-01

    The lack of reported complications related to lower extremity peripheral nerve blocks (PNBs) may be related to the relatively infrequent application of these techniques and to the fact that most such events go unpublished. Our current understanding of the factors that lead to neurologic complications after PNBs is limited. This is partly the result of our inability to conduct meaningful retrospective studies because of a lack of standard and objective monitoring and documentation procedures for PNBs. We report a case of permanent injury to the sciatic nerve after sciatic nerve block through the anterior approach and discuss mechanisms that may have led to the injury. Intraneural injection and nerve injury can occur in the absence of pain on injection and it may be heralded by high injection pressure (resistance).

  2. Anterior uveitis and diabetes mellitus: immunological study.

    Science.gov (United States)

    Castagna, I; Famà, F; Salmeri, G

    1995-01-01

    The association between anterior uveitis (AU) and diabetes mellitus (DM) has always been known. The purpose of this study was to estimate the incidence of this association and to consider a possible role of the cell-mediated immune system. During the years 1989-1992, 196 diabetics (66 patients affected by type I DM and 130 by type II DM) were studied. The study of the lymphocytic subsets and the measurement of the circulating immunocomplexes and autoantibodies (ANA, AMA, ADNA, ASMA, APCA) were carried out, and the results were compared with those of a control group. The results underline the correlation between AU and type I DM. Many immunological reactions could play a crucial role: the high levels of CD8 subsets found could be an expression of the unstable lymphocytic equilibrium.

  3. Dashed line relaxing retinotomy in the management of retinal detachment with anterior proliferative vitreoretinopathy

    Directory of Open Access Journals (Sweden)

    Tsen CL

    2015-04-01

    Full Text Available Chui-Lien Tsen,1 Yu-Harn Horng,1 Shwu-Jiuan Sheu1,2 1Department of Ophthalmology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; 2School of Medicine, National Yang-Ming University, Taipei, Taiwan Background: We describe the anatomical and functional outcomes of eyes that underwent a modified technique of relaxing retinotomy, dashed line relaxing retinotomy, in the management of retinal detachment with anterior proliferative vitreoretinopathy.Methods: We retrospectively reviewed 54 consecutive eyes in 52 patients who received pars plana vitrectomy with relaxing retinotomy during retinal detachment repair. Perfluorocarbon liquid (PFCL was used as a standard procedure to stabilize the retina during retinotomy to prevent slippage or inversion of the posterior flap. If PFCL was not available due to economic reasons, dashed line relaxing retinotomy was performed instead. Best-corrected visual acuity, slit-lamp biomicroscopy, intraocular pressure measurement, lens status, and fundus examination were analyzed. We excluded patients who were followed up <4 months.Results: Regarding anatomical success rates and visual outcomes, we found no significant differences between patients treated with intraoperative PFCL and those treated with dashed line relaxing retinotomy without PFCL.Conclusion: Compared to the simple and efficient PFCL-assisted relaxing retinotomy, dashed relaxing retinotomy is not the first choice when PFCL is available. Based on our results, this modified technique may offer an alternative in patients with anterior proliferative vitreoretinopathy for whom PFCL is not available. Keywords: perfluorocarbon liquid, PFCL 

  4. In vivo Confocal Microscopy in Differentiating Ipilimumab-Induced Anterior Uveitis from Metastatic Uveal Melanoma

    Directory of Open Access Journals (Sweden)

    Hayyam Kiratli

    2016-09-01

    Full Text Available This report aims to describe the facilitating role of in vivo confocal microscopy in differentiating inflammatory cells from a metastatic process in a patient with uveal melanoma and multiple systemic metastases who developed anterior uveitis while under ipilimumab treatment. A 43-year-old woman developed systemic metastases 11 months after treatment of amelanotic choroidal melanoma in her right eye with 30 Gy fractionated stereotactic radiotherapy. She first received temozolomide and then 4 cycles of ipilimumab 3 mg/kg/day. After the third cycle, severe anterior uveitis with coarse pigment clumps on the lens was seen in the left eye. Her left visual acuity declined from 20/20 to 20/80. Confocal microscopy revealed globular keratic precipitates with hyperreflective inclusions and endothelial blebs all suggestive of granulomatous uveitis. The uveitic reaction subsided after a 3-week course of topical corticosteroids, and her visual acuity was 20/20 again. Although uveal melanoma metastatic to the intraocular structures of the fellow eye is exceedingly rare and metastasis masquerading uveitis without any identifiable uveal lesion is even more unusual, it was still mandatory to rule out this distant possibility in our particular patient who already had widespread systemic metastases. Confocal microscopy was a useful complementary tool by identifying the inflammatory features of the keratic precipitates.

  5. Multisensory Training can Promote or Impede Visual Perceptual Learning of Speech Stimuli: Visual-Tactile versus Visual-Auditory Training

    Directory of Open Access Journals (Sweden)

    Silvio P Eberhardt

    2014-10-01

    Full Text Available In a series of studies we have been investigating how multisensory training affects unisensory perceptual learning with speech stimuli. Previously, we reported that Aaudiovisual training with speech stimuli can promote auditory-only perceptual learning in normal-hearing adults but can impede learning in congenitally deaf adults with late-acquired cochlear implants. Here, impeder and promoter effects were sought in normal-hearing adults who participated in lipreading training. In Experiment 1, visual-only (VO training on paired associations between CVCVC nonsense word videos and nonsense pictures demonstrated that VO words could be learned to a high level of accuracy even by poor lipreaders. In Experiment 2, visual-auditory (VA training in the same paradigm but with the addition of synchronous vocoded acoustic speech impeded VO learning of the stimuli in the paired-associates paradigm. In Experiment 3, the vocoded auditory-only (AO stimuli were shown to be less informative than the VO speech. Experiment 4 combined vibrotactile speech stimuli with the visual stimuli during training. Vibrotactile stimuli were shown to promote visual perceptual learning in participants whose training scores were similar. In Experiment 5, no-training controls were used to show that training with visual speech carried over to consonant identification of untrained CVCVC stimuli but not to lipreading words in sentences. Across this and previous studies, multisensory training effects depended on the functional relationship between pathways engaged during training. Two principles are proposed to account for stimulus effects: (1 Stimuli presented to the trainee’s primary perceptual pathway will impede learning by a lower-rank pathway. (2 Stimuli presented to the trainee’s lower rank perceptual pathway will promote learning by a higher-rank pathway. The mechanisms supporting these principles are discussed in light of multisensory reverse hierarchy theory.

  6. GABAa agonist reduces visual awareness: a masking-EEG experiment

    NARCIS (Netherlands)

    van Loon, A.M.; Scholte, H.S.; van Gaal, S.; van der Hoort, B.J.J.; Lamme, V.A.F.

    2012-01-01

    Consciousness can be manipulated in many ways. Here, we seek to understand whether two such ways, visual masking and pharmacological intervention, share a common pathway in manipulating visual consciousness. We recorded EEG from human participants who performed a backward-masking task in which they

  7. Fibular allograft and anterior plating for dislocations/fractures of the cervical spine

    Directory of Open Access Journals (Sweden)

    Ramnarain A

    2008-01-01

    Full Text Available Background: Subaxial cervical spine dislocations are common and often present with neurological deficit. Posterior spinal fusion has been the gold standard in the past. Pain and neck stiffness are often the presenting features and may be due to failure of fixation and extension of fusion mass. Anterior spinal fusion which is relatively atraumatic is thus favored using autogenous grafts and cages with anterior plate fixation. We evaluated fresh frozen fibular allografts and anterior plate fixation for anterior fusion in cervical trauma. Materials and Methods: Sixty consecutive patients with single-level dislocations or fracture dislocations of the subaxial cervical spine were recruited in this prospective study following a motor vehicle accident. There were 38 males and 22 females. The mean age at presentation was 34 years (range 19-67 years. The levels involved were C5/6 ( n = 36, C4/5 ( n = 15, C6/7 ( n = 7 and C3/4 ( n = 2. There were 38 unifacet dislocations with nine posterior element fractures and 22 were bifacet dislocations. Twenty-two patients had neurological deficit. Co-morbidities included hypertension ( n = 6, non-insulin-dependent diabetes mellitus ( n = 2 and asthma ( n = 1. All patients were initially managed on skull traction. Following reduction further imaging included Computerized Tomography and Magnetic Resonance Imaging. Patients underwent anterior surgery (discectomy, fibular allograft and plating. All patients were immobilized in a Philadelphia collar for eight weeks (range 7-12 weeks. Eight patients were lost to follow-up within a year. Follow-up clinical and radiological examinations were performed six-weekly for three months and subsequently at three-monthly intervals for 12 months. Pain was analyzed using the visual analogue scale (VAS. The mean follow-up was 19 months (range 14-39 months. Results: Eight lost to followup, hence 52 patients were considered for final evaluation. The neurological recovery was 1.1 Frankel

  8. Recovery from optic neuritis: an ROI-based analysis of LGN and visual cortical areas

    DEFF Research Database (Denmark)

    Korsholm, Kirsten; Madsen, Kristoffer Hougaard; Frederiksen, Jette L

    2007-01-01

    and neuronal plasticity in the cortical and subcortical visual pathways. To assess where recovery takes place along the visual pathway, visual activation was studied in the lateral geniculate nucleus (LGN), the main thalamic relay nucleus in the visual pathway and in three areas of the visual cortex......: the lateral occipital complexes (LOC), V1 and V2. We conducted a longitudinal functional magnetic resonance imaging (fMRI) study of regions of interest (ROI) of activation in LGN and visual cortex in 19 patients with acute ON at onset, 3 and 6 months from presentation. With fMRI we measured the activation......Optic neuritis (ON) is the first clinical manifestation in approximately 20% of patients with multiple sclerosis (MS). The inflammation and demyelination of the optic nerve are characterized by symptomatic visual impairment and retrobulbar pain, and associated with decreased visual acuity...

  9. Etiological aspects of anterior open bite

    Directory of Open Access Journals (Sweden)

    Stojanović Ljiljana

    2007-01-01

    Full Text Available Introduction. Open bite is a multifactorial phenomenon and no single factor can account for open-bite. Etiology plays an important role in diagnosis. Heredity, unfavorable growth patterns, incorrect jaw postoure, are the characteristics of skeletal open bite. Digit sucking. Depending on where the thumb is placed, a number of different types of dental problems can develop. Malocclusions of the late mixed or permanent dentitions, caused by thumb sucking are not self corrected and orthodontic treatment is necessary for their correction. Lymphatic tissue. In order to produce oral respiration, the mandible is postured inferiorly with the tongue protruded and resting against the oral floor. This postural alteration induces dental and skeletal modifications similar to those caused by thumb sucking. This may cause excessive eruption of the posterior teeth, leading to an increase in the vertical dimension of the face and result in development of anterior open bite. Tongue thrust. Tongue habits cause an anterior open bite or they develop secondarily to thumb sucking. In skeletal open bite the tongue habit acts as a secondary factor which helps to maintain or exacerbate the condition. Many orthodontists have had a discouraging experience of completing dental treatment, with what appeared to be good results, only to discover that the case had relapsed because the patient had a tongue thrust swallowing pattern. Conclusion. Dentoalveolar or habitual open bite is caused by habits, which influence the growth and development of dentoalveolar processes and contribute to occlusal disharmonies. Prior to eruption of adult dentition, open bite related to oral habits is usually not a concern as when the habits stop, because the erupting dentition tends to improve spontaneously. Treatment is usually not necessary until permanent teeth erupt (~6 years old. .

  10. CT-guided celiac plexus block with absolute alcohol : the anterior approach

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Min; Lee, Mi Suk; Jang, Young Ik; Kim, Jeong Hoi; Ym, Seong Hee; Lee, Jin Hee [Namwon Medical Center, Namwon (Korea, Republic of); Han, Young Min; Kim, Chong Soo; Choi, Ki Chul [Chonbuk National Univ. College of Medicine, Chonju (Korea, Republic of)

    1997-07-01

    To evaluate the safety and efficacy of CT-guided celiac plexus block (CPB) using an anterior approach, and to determine the role of CT in this procedure. CPB was attempted in 15 patients(10 men and 5 women;mean age, 62.3 years) with intractable upper abdominal pain due to terminal malignancy of the pancreas, liver, bowel,and kidney. To permit an anterior approach, patients lied supine on the CT scan table during the procedure. One or two 21-guage needles were placed just anterior to the diaphragmatic crus at or between the levels of the celiac and superior mesenteric arteries and 10-40ml of 99.9% alcohol was injected. Pain relief following the procedure was assessed and pain was graded on a visual analogue scale (VAS) from 0 to 10. There were no technical failures and no neurologic or hemorrhagic complications. Abdominal pain during alcohol injection occurred in all patients, and transient hypotension in three. One patient with recurrent cancer of the pancreatic head died of sepsis five days after the procedure;the cause of sepsis was difficult to determine, but there was thought to be a biliary source of infection. Two days after block, 13 of 15 procedures(86.7%) had produced at least partial pain relief;in 12 patients, relief was good. With CT guidance, more directed positioning of the needle is possible, allowing alcohol to be deposited in specific ganglion areas. CT-guided celiac plexus block using an anterior approach was an easy and effective way of reducing intractable upper abdominal pain due to terminal malignancies. CT guidance allowed precise needle placement and a safer procedure.

  11. The neurology of visual acuity.

    Science.gov (United States)

    Frisén, L

    1980-09-01

    A series of patients with well defined lesions of various parts of the visual pathways was studied in an attempt to iluminate the neuropathophysiology of visual acuity. Acuity was found to remain normal in all cases with unilateral retrochiasmal lesions, including those of the optic tract. Bilateral retrochiasmal lesions involving the foveal nerve fibres on both sides impaired acuity to the same degree in both eyes. Lateral chiasmal lesions regularly produced impaired acuity in the ipsilateral eye. Midchiasmal lesions commonly led to an impairment of visual acuity in both eyes, usually asymmetrically, and roughly proportionate to the severity of the visual field defect. Compression optic neuropathy was found to reduce acuity in rough proportion to the severity of compression. It was concluded that acuity remains normal as long as either the crossing or the non-crossing neural outflow from the retinal fovea remains intact: acuity fails only when both sets of nerve fibres are compromised. A properly executed acuity test seems to be a powerful tool for detecting such conditions. The lower limit of normal acuity should never be set below 1.0 or 20/20: even this level is clearly subnormal in many subjects.

  12. Diverse ETS transcription factors mediate FGF signaling in the Ciona anterior neural plate.

    Science.gov (United States)

    Gainous, T Blair; Wagner, Eileen; Levine, Michael

    2015-03-15

    The ascidian Ciona intestinalis is a marine invertebrate belonging to the sister group of the vertebrates, the tunicates. Its compact genome and simple, experimentally tractable embryos make Ciona well-suited for the study of cell-fate specification in chordates. Tunicate larvae possess a characteristic chordate body plan, and many developmental pathways are conserved between tunicates and vertebrates. Previous studies have shown that FGF signals are essential for neural induction and patterning at sequential steps of Ciona embryogenesis. Here we show that two different ETS family transcription factors, Ets1/2 and Elk1/3/4, have partially redundant activities in the anterior neural plate of gastrulating embryos. Whereas Ets1/2 promotes pigment cell formation in lateral lineages, both Ets1/2 and Elk1/3/4 are involved in the activation of Myt1L in medial lineages and the restriction of Six3/6 expression to the anterior-most regions of the neural tube. We also provide evidence that photoreceptor cells arise from posterior regions of the presumptive sensory vesicle, and do not depend on FGF signaling. Cells previously identified as photoreceptor progenitors instead form ependymal cells and neurons of the larval brain. Our results extend recent findings on FGF-dependent patterning of anterior-posterior compartments in the Ciona central nervous system.

  13. Acute anterior uveitis after discontinuation of tocilizumab in a patient with rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Sato T

    2014-01-01

    Full Text Available Tomohito Sato,1 Shinya Minakuchi,1 Manabu Mochizuki,2 Masaru Takeuchi11Department of Ophthalmology, National Defense Medical College, Saitama, Japan; 2Department of Ophthalmology and Visual Science, Tokyo Medical and Dental University Graduate School of Medicine, Tokyo, JapanBackground: Tocilizumab is a humanized monoclonal anti-interleukin-6 (IL-6 receptor antibody and has been approved in Japan for the treatment of Castleman's disease, rheumatoid arthritis (RA, and systemic juvenile idiopathic arthritis. Conjunctivitis and dry eye are known ocular adverse effects, but uveitis has not been reported.Case report: A 72-year-old woman had undergone bilateral cataract surgery without complications. Six months after the surgery, she was diagnosed with RA and treated with tocilizumab infusion every 4 weeks. However, severe malaise and dizziness occurred after the third tocilizumab infusion, and the treatment was suspended. Since the symptoms associated with RA had resolved, she was followed without any medication thereafter. At 5 weeks after the third tocilizumab infusion, she developed severe anterior inflammation with hypopyon in her left eye, and her visual acuity dropped to less than 2/200. Considering her age and history of cataract surgery, endophthalmitis was suspected and a vitrectomy was performed, but no pathogens were detected from the intraocular fluid samples collected during surgery. The ocular inflammation was gradually resolved with systemic antibiotics and corticosteroids. However, severe anterior uveitis recurred in the same eye during the tapering of the systemic corticosteroids, when the aqueous humor IL-6 level was 46,100 pg/mL. The recurrent ocular inflammation was resolved with increased doses of topical and systemic corticosteroids, and the patient has since remained relapse-free. No symptom of inflammation was observed in the right eye during the follow-up period.Conclusion: This case indicates a possibility that acute

  14. Snowflake Visualization

    Science.gov (United States)

    Bliven, L. F.; Kucera, P. A.; Rodriguez, P.

    2010-12-01

    NASA Snowflake Video Imagers (SVIs) enable snowflake visualization at diverse field sites. The natural variability of frozen precipitation is a complicating factor for remote sensing retrievals in high latitude regions. Particle classification is important for understanding snow/ice physics, remote sensing polarimetry, bulk radiative properties, surface emissivity, and ultimately, precipitation rates and accumulations. Yet intermittent storms, low temperatures, high winds, remote locations and complex terrain can impede us from observing falling snow in situ. SVI hardware and software have some special features. The standard camera and optics yield 8-bit gray-scale images with resolution of 0.05 x 0.1 mm, at 60 frames per second. Gray-scale images are highly desirable because they display contrast that aids particle classification. Black and white (1-bit) systems display no contrast, so there is less information to recognize particle types, which is particularly burdensome for aggregates. Data are analyzed at one-minute intervals using NASA's Precipitation Link Software that produces (a) Particle Catalogs and (b) Particle Size Distributions (PSDs). SVIs can operate nearly continuously for long periods (e.g., an entire winter season), so natural variability can be documented. Let’s summarize results from field studies this past winter and review some recent SVI enhancements. During the winter of 2009-2010, SVIs were deployed at two sites. One SVI supported weather observations during the 2010 Winter Olympics and Paralympics. It was located close to the summit (Roundhouse) of Whistler Mountain, near the town of Whistler, British Columbia, Canada. In addition, two SVIs were located at the King City Weather Radar Station (WKR) near Toronto, Ontario, Canada. Access was prohibited to the SVI on Whistler Mountain during the Olympics due to security concerns. So to meet the schedule for daily data products, we operated the SVI by remote control. We also upgraded the

  15. Age-Dependent Cortical Thinning of Peripheral Visual Field Representations in Primary Visual Cortex.

    Science.gov (United States)

    Griffis, Joseph C; Burge, Wesley K; Visscher, Kristina M

    2016-01-01

    The cerebral cortex changes throughout the lifespan, and the cortical gray matter in many brain regions becomes thinner with advancing age. Effects of aging on cortical thickness (CT) have been observed in many brain regions, including areas involved in basic perceptual functions such as processing visual inputs. An important property of early visual cortices is their topographic organization-the cortical structure of early visual areas forms a topographic map of retinal inputs. Primary visual cortex (V1) is considered to be the most basic cortical area in the visual processing hierarchy, and is topographically organized from posterior (central visual representation) to anterior (peripheral visual representation) along the calcarine sulcus. Some studies have reported strong age-dependent cortical thinning in portions of V1 that likely correspond to peripheral visual representations, while there is less evidence of substantial cortical thinning in central V1. However, the effect of aging on CT in V1 as a function of its topography has not been directly investigated. To address this gap in the literature, we estimated the CT of different eccentricity sectors in V1 using T1-weighted MRI scans acquired from groups of healthy younger and older adults, and then assessed whether between-group differences in V1 CT depended on cortical eccentricity. These analyses revealed age-dependent cortical thinning specific to peripheral visual field representations in anterior portions of V1, but did not provide evidence for age-dependent cortical thinning in other portions of V1. Additional analyses found similar effects when analyses were restricted to the gyral crown, sulcul depth and sulcul wall, indicating that these effects are not likely due to differences in gyral/sulcul contributions to our regions of interest (ROI). Importantly, this finding indicates that age-dependent changes in cortical structure may differ among functionally distinct zones within larger canonical

  16. Pupil-occluding organized hyphema anterior to the intraocular lens treated by neodymium: yttrium-aluminum-garnet laser: a case report

    Science.gov (United States)

    Kim, Moosang; Lee, Seung-Jun; Han, Sang Beom; Yang, Hee Kyung; Hyon, Joon Young

    2016-01-01

    We report, to our best knowledge, the first case of treatment of pupil-occluding postoperative organized hyphema anterior to the intraocular lens (IOL) using neodymium: yttrium-aluminum-garnet (Nd:YAG) laser. A 78-year-old Asian female underwent uneventful cataract operation. She had been taking aspirin, which she discontinued 1 week before surgery. Iris prolapse occurred at the end of the surgery, which led to intracameral bleeding. Two weeks later, her best-corrected visual acuity was hand motion. Although hyphema had decreased, pupil-occluding organized hematoma had formed anterior to the IOL. The blood clot anterior to the IOL was removed using Nd:YAG laser. One week later, although the hematoma anterior to the IOL resolved, endocapsular hematoma was observed, which was dispersed with Nd:YAG laser posterior capsulotomy. Two weeks later, her best-corrected visual acuity improved to 20/60. There was no complication associated with Nd:YAG laser. In conclusion, pupil-occluding organized hyphema anterior to the IOL can occur as a complication of cataract surgery, in which Nd:YAG laser can be a useful treatment option. PMID:27462181

  17. Functional organization of telencephalic visual association fields in pigeons.

    Science.gov (United States)

    Stacho, Martin; Ströckens, Felix; Xiao, Qian; Güntürkün, Onur

    2016-04-15

    Birds show remarkable visual abilities that surpass most of our visual psychophysiological abilities. In this study, we investigated visual associative areas of the tectofugal visual system in pigeons. Similar to the condition in mammals, ascending visual pathways in birds are subdivided into parallel form/color vs. motion streams at the thalamic and primary telencephalic level. However, we know practically nothing about the functional organization of those telencephalic areas that receive input from the primary visual telencephalic fields. The current study therefore had two objectives: first, to reveal whether these visual associative areas of the tectofugal system are activated during visual discrimination tasks; second, to test whether separated form/color vs. motion pathways can be discerned among these association fields. To this end, we trained pigeons to discriminate either form/color or motion stimuli and used the immediate early gene protein ZENK to capture the activity of the visual associative areas during the task. We could indeed identify several visual associative telencephalic structures by activity pattern changes during discriminations. However, none of these areas displayed a difference between form/color vs. motion sessions. The presence of such a distinction in thalamo-telencephalic, but not in further downstream visual association areas opens the possibility that these separate streams converge very early in birds, which possibly minimizes long-range connections due to the evolutionary pressure toward miniaturized brains.

  18. Visualizing Mobility of Public Transportation System.

    Science.gov (United States)

    Zeng, Wei; Fu, Chi-Wing; Arisona, Stefan Müller; Erath, Alexander; Qu, Huamin

    2014-12-01

    Public transportation systems (PTSs) play an important role in modern cities, providing shared/massive transportation services that are essential for the general public. However, due to their increasing complexity, designing effective methods to visualize and explore PTS is highly challenging. Most existing techniques employ network visualization methods and focus on showing the network topology across stops while ignoring various mobility-related factors such as riding time, transfer time, waiting time, and round-the-clock patterns. This work aims to visualize and explore passenger mobility in a PTS with a family of analytical tasks based on inputs from transportation researchers. After exploring different design alternatives, we come up with an integrated solution with three visualization modules: isochrone map view for geographical information, isotime flow map view for effective temporal information comparison and manipulation, and OD-pair journey view for detailed visual analysis of mobility factors along routes between specific origin-destination pairs. The isotime flow map linearizes a flow map into a parallel isoline representation, maximizing the visualization of mobility information along the horizontal time axis while presenting clear and smooth pathways from origin to destinations. Moreover, we devise several interactive visual query methods for users to easily explore the dynamics of PTS mobility over space and time. Lastly, we also construct a PTS mobility model from millions of real passenger trajectories, and evaluate our visualization techniques with assorted case studies with the transportation researchers.

  19. Tireoide ectópica no mediastino anterior Ectopic thyroid in the anterior mediastinum

    Directory of Open Access Journals (Sweden)

    Maria José Araújo da Cunha Guimarães

    2009-04-01

    Full Text Available A ectopia de tireoide é rara, e a sua localização no mediastino anterior é excepcional, estando descritos apenas 5 casos nos últimos 30 anos. Os autores apresentam 2 casos clínicos, além de uma revisão da literatura abordando a etiologia, a embriologia e manifestações clínicas de ectopia de tireoide.Ectopic thyroid is a rare condition, and its location in the anterior mediastinum is even rarer, there having been only 5 reported cases in the past 30 years. Here, we describe 2 clinical cases and present a review of the literature regarding the etiology, embryology and clinical manifestations of ectopic thyroid.

  20. Visuals for Information.

    Science.gov (United States)

    Pettersson, Rune

    This report focuses on the visual component of verbo-visual literacy, a communications concept involving the production, transmission, and perception of verbal and visual images. Five current problem areas in verbal-visual research are introduced and discussed: (1) communication (communication models, media consumption, new media, the information…

  1. Experimental Study on the Prevention of Anterior Segment Ischemia by Preservation of Anterior Ciliary Vessels

    Institute of Scientific and Technical Information of China (English)

    Yanna Li; Guanghuan Mai; Zhijian Wang; Xinping Yu; Huanyun Yu; Yan Guo; Xiaoming Lin; Daming Deng; Ying Kang

    2003-01-01

    Purpose: To observe the effect of preserving anterior ciliary vessels (ACVs) on anteriorsegments of rabbit eyes undergoing tenotomy of extraocular muscles.Methods: Thirty-two adult New Zealand white rabbits were divided into four groups.Same procedures were done in both eyes in each group except that left eyes underwentpreservation of ACVs. In the first group medial and lateral recti, in the second group,superior and inferior recti, in the third group, medial, lateral and superior or inferior rectiand in the fourth group, all four recti, underwent tenotomy. Slit-lamp examination,intraocular pressure (IOP) measurement, total protein and lactic acid quantification inaqueous humor were done in all eyes pre- and post-operatively. By four weeks afteroperation, the eyes were enucleated for histological examination and electron microscopy.All data were analyzed using SPSS version 10.Results: In the left eyes of both group 1 and group 2, no inflammatory response wasobserved. In the left eyes of group 3 and 4, we observed mild inflammatory response withslit-lamp examination, which disappeared in one wk. However, we did not findsignificant changes in IOP, total protein and lactic acid of aqueous humor, histology andelectron microscopic examination in these groups. In the right eyes in group 2, 3 and 4,we observed moderate to severe inflammatory changes, a few even developed anteriorsegment ischemia, appeared as decreased IOP, increased total protein and lactic acid inaqueous humor, along with pathological and electron-microscopic changes.Conclusion: Simultaneous tenotomy of three or four recti or two vertical recti on one eyemay decrease anterior segment blood flow even lead to ischemia. ACVs preservation mayprotect the blood circulation in anterior segment. Our study suggests that ACVspreservation in strabismus surgeries especially those involving multi-recti tenotomies mayprevent potential anterior segment ischemia.

  2. Transphyseal anterior cruciate ligament reconstruction in a skeletally immature knee using anterior tibialis allograft.

    Science.gov (United States)

    Cho, Yool; Jang, Soo-Jin; Son, Jung-Hwan

    2011-05-18

    Anterior cruciate ligament (ACL) injury in the skeletally immature individual is being recognized with increasing frequency. Nonoperative treatment of ACL injuries in skeletally immature patients have not been favorable. Surgical treatment options for complete ACL tears include primary ligament repair, extraarticular tenodesis, transphyseal reconstruction, partial transphyseal reconstruction, and physeal-sparing reconstruction. The advantage of transphyseal reconstruction is placement of the graft tissue in an isometric position, which provides better results, according to the literature. The potential disadvantage is angular or limb-length discrepancy caused by physeal violation. Controversy exists in allograft selection about whether bone or soft tissue passes into physes. The use of standard tunnels provides reliable results, but carries the risk of iatrogenic growth disturbance from physeal injury.This article presents 4 cases of transphyseal ACL reconstruction using anterior tibialis allograft in skeletally immature patients that had satisfactory functional outcomes with no growth disturbances. This is the first report of transphyseal ACL reconstruction using anterior tibialis allograft in skeletally immature patients in the English-speaking literature. All patients underwent transphyseal ACL reconstruction using anterior tibialis tendon allograft. None of the patients had angular deformities. No early physeal arrest was measured between the preoperative and postoperative radiographs. At last follow-up, the results of the Lachman test were normal for 3 patients and nearly normal for 1 patient. All patients demonstrated full range of knee motion (comparing the reconstructed knee to the contralateral knee). The results of the pivot-shift test were normal for 3 patients and nearly normal for 1 patient. No patients reported giving way.

  3. A BOLD signature of eyeblinks in the visual cortex.

    Science.gov (United States)

    Hupé, Jean-Michel; Bordier, Cécile; Dojat, Michel

    2012-05-15

    We are usually unaware of the brief but large illumination changes caused by blinks, presumably because of blink suppression mechanisms. In fMRI however, increase of the BOLD signal was reported in the visual cortex, e.g. during blocks of voluntary blinks (Bristow, Frith and Rees, 2005) or after spontaneous blinks recorded during the prolonged fixation of a static stimulus (Tse, Baumgartner and Greenlee, 2010). We tested whether such activation, possibly related to illumination changes, was also present during standard fMRI retinotopic and visual experiments and was large enough to contaminate the BOLD signal we are interested in. We monitored in a 3T scanner the eyeblinks of 14 subjects who observed three different types of visual stimuli, including periodic rotating wedges and contracting/expanding rings, event-related Mondrians and graphemes, while fixating. We performed event-related analyses on the set of detected spontaneous blinks. We observed large and widespread BOLD responses related to blinks in the visual cortex of every subject and whatever the visual stimulus. The magnitude of the modulation was comparable to visual stimulation. However, blink-related activations lay mostly in the anterior parts of retinotopic visual areas, coding the periphery of the visual field well beyond the extent of our stimuli. Blinks therefore represent an important source of BOLD variations in the visual cortex and a troublesome source of noise since any correlation, even weak, between the distribution of blinks and a tested protocol could trigger artifactual activities. However, the typical signature of blinks along the anterior calcarine and the parieto-occipital sulcus allows identifying, even in the absence of eyetracking, fMRI protocols possibly contaminated by a heterogeneous distribution of blinks.

  4. Temporal and spatial requirements for Nodal-induced anterior mesendoderm and mesoderm in anterior neurulation.

    Science.gov (United States)

    Gonsar, Ngawang; Coughlin, Alicia; Clay-Wright, Jessica A; Borg, Bethanie R; Kindt, Lexy M; Liang, Jennifer O

    2016-01-01

    Zebrafish with defective Nodal signaling have a phenotype analogous to the fatal human birth defect anencephaly, which is caused by an open anterior neural tube. Previous work in our laboratory found that anterior open neural tube phenotypes in Nodal signaling mutants were caused by lack of mesendodermal/mesodermal tissues. Defects in these mutants are already apparent at neural plate stage, before the neuroepithelium starts to fold into a tube. Consistent with this, we found that the requirement for Nodal signaling maps to mid-late blastula stages. This timing correlates with the timing of prechordal plate mesendoderm and anterior mesoderm induction, suggesting these tissues act to promote neurulation. To further identify tissues important for neurulation, we took advantage of the variable phenotypes in Nodal signaling-deficient sqt mutant and Lefty1-overexpressing embryos. Statistical analysis indicated a strong, positive correlation between a closed neural tube and presence of several mesendoderm/mesoderm-derived tissues (hatching glands, cephalic paraxial mesoderm, notochord, and head muscles). However, the neural tube was closed in a subset of embryos that lacked any one of these tissues. This suggests that several types of Nodal-induced mesendodermal/mesodermal precursors are competent to promote neurulation.

  5. Review for the generalist: evaluation of anterior knee pain

    Directory of Open Access Journals (Sweden)

    Houghton Kristin M

    2007-05-01

    Full Text Available Abstract Anterior knee pain is common in children and adolescents. Evaluation and management is challenging and requires a thorough history and physical exam, and understanding of the pediatric skeleton. This article will review common causes of chronic anterior knee pain in the pediatric population with a focus on patellofemoral pain.

  6. [Key points in anterior esthetic restorations with all ceramic].

    Science.gov (United States)

    Luo, Xiaoping; Qian, Dongdong; Yuan, Yu; Meng, Xiangfeng

    2013-04-01

    This paper introduced the key points in fabricating anterior esthetic restorations with all ceramic materials, including pre-operative smile design, standard tooth preparation, provisional restoration fabrication, all ceramic materials selection, all ceramic restoration bonding, ceramic crack and fracture prevention. And then, the authors summarized and reviewed the clinical common problems in anterior esthetic restorations.

  7. Modified Anchor Shaped Post Core Design for Primary Anterior Teeth

    OpenAIRE

    R. Rajesh; Kusai Baroudi; K. Bala Kasi Reddy; Praveen, B. H.; V. Sumanth Kumar; Amit, S

    2014-01-01

    Restoring severely damaged primary anterior teeth is challenging to pedodontist. Many materials are tried as a post core but each one of them has its own drawbacks. This a case report describing a technique to restore severely damaged primary anterior teeth with a modified anchor shaped post. This technique is not only simple and inexpensive but also produces better retention.

  8. Modified Anchor Shaped Post Core Design for Primary Anterior Teeth

    Directory of Open Access Journals (Sweden)

    R. Rajesh

    2014-01-01

    Full Text Available Restoring severely damaged primary anterior teeth is challenging to pedodontist. Many materials are tried as a post core but each one of them has its own drawbacks. This a case report describing a technique to restore severely damaged primary anterior teeth with a modified anchor shaped post. This technique is not only simple and inexpensive but also produces better retention.

  9. Modified anchor shaped post core design for primary anterior teeth.

    Science.gov (United States)

    Rajesh, R; Baroudi, Kusai; Reddy, K Bala Kasi; Praveen, B H; Kumar, V Sumanth; Amit, S

    2014-01-01

    Restoring severely damaged primary anterior teeth is challenging to pedodontist. Many materials are tried as a post core but each one of them has its own drawbacks. This a case report describing a technique to restore severely damaged primary anterior teeth with a modified anchor shaped post. This technique is not only simple and inexpensive but also produces better retention.

  10. [Bilateral anterior uveiopapillitis, suspicious of Lyme disease--case report].

    Science.gov (United States)

    Nicula, Cristina; Nicula, D; Rusu, Ioana; Popescu, Raluca

    2013-01-01

    We present the case of a patient which associated bilateral anterior uveitis manifestations with those of bilateral anterior inflammatory optic neuropathy. We followed the evolution of the case under treatment and we discussed the differential diagnosis and the association of the two ocular pathologies.

  11. Anterior urethral recurrence of superficial bladder cancer: its clinical significance.

    Directory of Open Access Journals (Sweden)

    Saika T

    2003-12-01

    Full Text Available The aim of this study was to reveal the clinical features of anterior urethral recurrence in patients with superficial bladder cancer, and to determine the appropriate treatment. Three hundred and three patients with superficial bladder cancer, who were newly diagnosed and initially treated conservatively in our hospital between 1965 and 1990, were followed for at least 5 years and their clinical outcomes were analyzed. Clinical factors, including anterior urethral recurrence, were evaluated statistically regarding tumor progression. Eight patients (2.6% had anterior urethral recurrence following superficial bladder cancer. Twenty-four patients (7.9% had tumor progression and 149 (49.2% had tumor recurrence. In a multivariate analysis using a logistic model, anterior urethral recurrence was the most important factor, followed by histological grade. Four of 5 patients who were treated for anterior urethral recurrent tumors by transurethral resection showed progression and died of the cancer within one year. Two of the remaining three patients who underwent radical cysto-urethrectomy at the time of anterior urethral recurrence survived. Anterior urethral recurrence following superficial bladder cancer is a predictor for rapid subsequent malignant progression. Once there is anterior urethral recurrence, radical intensive therapy, including radical cysto-urethrectomy, should be carried out immediately.

  12. Anterior commissure absence without callosal agenesis: a new brain malformation.

    Science.gov (United States)

    Mitchell, T N; Stevens, J M; Free, S L; Sander, J W; Shorvon, S D; Sisodiya, S M

    2002-04-23

    The authors report a novel human brain malformation characterized by the absence of the anterior commissure without callosal agenesis, but associated with gross unilateral panhemispheric malformation incorporating subependymal heterotopia, subcortical heterotopia, and gyral abnormalities including temporal malformation and polymicrogyria. In contrast, a normal anterior commissure was found in 125 control subjects and in 113 other subjects with a range of brain malformations.

  13. Agenesis of internal carotid artery associated with congenital anterior hypopituitarism

    Energy Technology Data Exchange (ETDEWEB)

    Moon, W.-J. [Department of Diagnostic Radiology, Samsung Medical Center, Seoul (Korea); Institute of Neuroradiology, University of Frankfurt (Germany); Porto, L.; Lanfermann, H.; Zanella, F.E. [Institute of Neuroradiology, University of Frankfurt (Germany); Weis, R. [Department of Pediatric Neurology, University of Frankfurt (Germany)

    2002-02-01

    We report a rare case of unilateral agenesis of the internal carotid artery in association with congenital anterior hypopituitarism. The collateral circulation is supplied by a transsellar intercavernous anastomotic vessel connecting the internal carotid arteries. These abnormalities are well depicted on MRI and MRA. The agenesis of the internal carotid artery may explain the pathogenesis of some of congenital anterior hypopituitarism. (orig.)

  14. Reconstruction of the Anterior Cruciate Ligament : Alternative Strategies

    NARCIS (Netherlands)

    van Eijk, F.

    2009-01-01

    This thesis describes the long-term results of reconstruction of the anterior cruciate ligament with an allograft. Due to the poor results found, further studies were performed to investigate alternative strategies for reconstruction of the anterior cruciate ligament in the field of tissue engineeri

  15. Bilateral agenesis of the anterior cruciate ligament: MRI evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Bedoya, Maria A.; Jaramillo, Diego [The Children' s Hospital of Philadelphia, Radiology Department, Philadelphia, PA (United States); McGraw, Michael H. [Hospitalof theUniversityof Pennsylvania, Divisionof Orthopaedics, Philadelphia, PA (United States); Wells, Lawrence [The Children' s Hospital of Philadelphia, Division of Orthopaedics, Philadelphia, PA (United States)

    2014-09-15

    Bilateral agenesis of the anterior cruciate ligament (ACL) is extremely rare. We describe a 13-year-old girl who presented with bilateral knee pain without history of trauma; she has two family members with knee instability. Magnetic resonance imaging showed bilateral absence of the ACL, and medial posterior horn meniscal tears. Bilateral arthroscopic partial meniscectomy and anterior cruciate ligament reconstruction was performed. (orig.)

  16. Visual Analysis of Key Signal Protein in Calcium and ROS Pathway%钙和ROS通路关键信号蛋白的可视化分析研究报告

    Institute of Scientific and Technical Information of China (English)

    林金星; 李瑞丽

    2016-01-01

    We have developed a novel affinity labeling method based on DNA-templated photocrosslinking chemistry. DPAL uses a modular system to dissect binding from other functions that are usually combined in one probe, therefore simplifying probe design and preparation. Structure-activity relationship information on acceptable modification site on the SM is still required as any affinity probes. Then, we report a genetically encoded copper(I) probe capable of monitoring copper fluctuations inside living cells. We insert the copper regulatory protein Ace1 into a yellow fluorescent protein, which selectively binds copper(I) and generates improved copper(I) probes. To study how AMTs are regulated in the presence of ammonium, we used variable-angle total internal reflection fluorescence microscopy and fluorescence cross-correlation spectroscopy for single-particle fluorescence imaging of EGFP-tagged AMT1;3 on the plasma membrane of Arabidopsis root cells at various ammonium levels. We demonstrated that AMT1;3-EGFP dynamically appeared and disappeared on the plasma membrane as moving fluorescent spots in low oligomeric states under N-deprived and N-sufficient conditions. Under external high-ammonium stress, however, AMT1;3-EGFPs were found to amass into clusters, which were then internalized into the cytoplasm. A similar phenomenon also occurred in the glutamine synthetase mutant gln1;2 background. Single-particle analysis of AMT1;3-EGFPs in the clathrin heavy chain 2 mutant (chc2 mutant) and Flotllin1 artificial microRNA (Flot1 amiRNA) backgrounds, together with chemical inhibitor treatments, demonstrated that the endocytosis of AMT1;3 clusters induced by high-ammonium stress could occur mainly through clathrin-mediated endocytic pathways, but the contribution of microdomain-associated endocytic pathway cannot be excluded in the internalization. Our results revealed that the clustering and endocytosis of AMT1;3 provides an effective mechanism by which plant cells can avoid

  17. Expression of small leucine-rich proteoglycans in rat anterior pituitary gland.

    Science.gov (United States)

    Horiguchi, Kotaro; Syaidah, Rahimi; Fujiwara, Ken; Tsukada, Takehiro; Ramadhani, Dini; Jindatip, Depicha; Kikuchi, Motoshi; Yashiro, Takashi

    2013-01-01

    Proteoglycans are components of the extracellular matrix and comprise a specific core protein substituted with covalently linked glycosaminoglycan chains. Small leucine-rich proteoglycans (SLRPs) are a major family of proteoglycans and have key roles as potent effectors in cellular signaling pathways. Research during the last two decades has shown that SLRPs regulate biological functions in many tissues such as skin, tendon, kidney, liver, and heart. However, little is known of the expression of SLRPs, or the characteristics of the cells that produce them, in the anterior pituitary gland. Therefore, we have determined whether SLRPs are present in rat anterior pituitary gland. We have used real-time reverse transcription with the polymerase chain reaction to analyze the expression of SLRP genes and have identified the cells that produce SLRPs by using in situ hybridization with a digoxigenin-labeled cRNA probe. We have clearly detected the mRNA expression of SLRP genes, and cells expressing decorin, biglycan, fibromodulin, lumican, proline/arginine-rich end leucine-rich repeat protein (PRELP), and osteoglycin are located in the anterior pituitary gland. We have also investigated the possible double-staining of SLRP mRNA and pituitary hormones, S100 protein (a marker of folliculostellate cells), desmin (a marker of capillary pericytes), and isolectin B4 (a marker of endothelial cells). Decorin, biglycan, fibromodulin, lumican, PRELP, and osteoglycin mRNA have been identified in S100-protein-positive and desmin-positive cells. Thus, we conclude that folliculostellate cells and pericytes produce SLRPs in rat anterior pituitary gland.

  18. Using transparency in visualization

    OpenAIRE

    2011-01-01

    Over the last two decades, there have been a growing number of applications for transparency in visualization. Transparency is a visual feature that provides solutions to certain fundamental visualization problems. Currently, there is insufficient research regarding the benefits and the limitations of using transparency in visualization. The lack of research on this topic becomes more apparent when we compare the amount of research done towards applying colour in visualization. This thesis at...

  19. Anterior endoderm and head induction in early vertebrate embryos.

    Science.gov (United States)

    de Souza, F S; Niehrs, C

    2000-05-01

    Early work on the formation of the vertebrate body axis indicated the existence of separate head- and trunk-inducing regions in Spemann's organizer of the amphibian gastrula. In mammals some head-organizing activity may be located in anterior visceral (extraembryonic) endoderm (AVE). By analogy, the equivalent structure in the Xenopus laevis gastrula, the anterior endoderm, has been proposed to be the amphibian head organizer. Here we review recent data that challenge this notion and indicate that the involvement of AVE in head induction seems to be an exclusively mammalian characteristic. In X. laevis and chick, it is the prechordal endomesoderm that is the dominant source of head-inducing signals during early gastrulation. Furthermore, head induction in mammals needs a combination of signals from anterior primitive endoderm, prechordal plate, and anterior ectoderm. Thus, despite the homology of vertebrate anterior primitive endoderm, a role in head induction seems not to be conserved.

  20. Variant attachments of the anterior horn of the medial meniscus.

    Science.gov (United States)

    Jakubowicz, Marian; Ratajczak, Wojciech; Pytel, Andrzej

    2003-01-01

    The purpose of this study was to analyse the occurrence of variants of anomalous insertions of the anterior horn of the medial meniscus in human knee joints. The study was carried out on 78 human lower limbs of both sexes (42 males and 36 females). Out of 78 knee joints, 10 knee joints (12.82%) presented atypical attachments of the anterior horn of the medial meniscus. In 9 cases we found that the anterior horn of the medial meniscus was attached to the transverse ligament of the knee and in 1 case it was attached to the coronary ligament. In the remaining cases the anterior horn of the medial meniscus was attached to the anterior intercondylar area of the tibia.

  1. Method for measuring anterior chamber volume by image analysis

    Science.gov (United States)

    Zhai, Gaoshou; Zhang, Junhong; Wang, Ruichang; Wang, Bingsong; Wang, Ningli

    2007-12-01

    Anterior chamber volume (ACV) is very important for an oculist to make rational pathological diagnosis as to patients who have some optic diseases such as glaucoma and etc., yet it is always difficult to be measured accurately. In this paper, a method is devised to measure anterior chamber volumes based on JPEG-formatted image files that have been transformed from medical images using the anterior-chamber optical coherence tomographer (AC-OCT) and corresponding image-processing software. The corresponding algorithms for image analysis and ACV calculation are implemented in VC++ and a series of anterior chamber images of typical patients are analyzed, while anterior chamber volumes are calculated and are verified that they are in accord with clinical observation. It shows that the measurement method is effective and feasible and it has potential to improve accuracy of ACV calculation. Meanwhile, some measures should be taken to simplify the handcraft preprocess working as to images.

  2. Custom Visualization without Real Programming

    DEFF Research Database (Denmark)

    Pantazos, Kostas

    Information Visualization tools have simplified visualization development. Some tools help simple users construct standard visualizations; others help programmers develop custom visualizations. This thesis contributes to the field of Information Visualization and End-User Development. The first c...

  3. Inhibitory Smads and bone morphogenetic protein (BMP) modulate anterior photoreceptor cell number during planarian eye regeneration.

    Science.gov (United States)

    González-Sastre, Alejandro; Molina, Ma Dolores; Saló, Emili

    2012-01-01

    Planarians represent an excellent model to study the processes of body axis and organ re-specification during regeneration. Previous studies have revealed a conserved role for the bone morphogenetic protein (BMP) pathway and its intracellular mediators Smad1/5/8 and Smad4 in planarian dorsoventral (DV) axis re-establishment. In an attempt to gain further insight into the role of this signalling pathway in planarians, we have isolated and functionally characte-rized the inhibitory Smads (I-Smads) in Schmidtea mediterranea. Two I-Smad homologues have been identified: Smed-smad6/7-1 and Smed-smad6/7-2. Expression of smad6/7-1 was detected in the parenchyma, while smad6/7-2 was found to be ex-pressed in the central nervous system and the eyes. Neither single smad6/7-1 and smad6/7-2 nor double smad6/7-1,-2 silencing gave rise to any apparent disruption of the DV axis. However, both regenerating and intact smad6/7-2 (RNAi) planarians showed defects in eye morphogenesis and displayed small, rounded eyes that lacked the anterior subpopulation of photoreceptor cells. The number of pigment cells was also reduced in these animals at later stages of regeneration. In contrast, after low doses of Smed-bmp(RNAi), planarians regenerated larger eyes in which the anterior subpopulation of photoreceptor cells was expanded. Our results suggest that Smed-smad6/7-2 and Smed-bmp control the re-specification and maintenance of anterior photoreceptor cell number in S. mediterranea.

  4. Vision and visual information processing in cubozoans

    DEFF Research Database (Denmark)

    Bielecki, Jan

    relationship between acuity and light sensitivity. Animals have evolved a wide variety of solutions to this problem such as folded membranes, to have a larger receptive surfaces, and lenses, to focus light onto the receptive membranes. On the neural capacity side, complex eyes demand huge processing network...... to analyse the received information, illustrated by the fact that one third of the human brain is devoted to visual information processing. The cost of maintaining such neural network deter most organisms from investing in the camera type option, if possible, and settle for a model that will more precisely...... fit their need. Visual neuroethology integrates optics, sensory equipment, neural network and motor output to explain how animals can perform behaviour in response to a specific visual stimulus. In this doctoral thesis, I will elucidate the individual steps in a visual neuroethological pathway...

  5. The relationship between the morphological features of A1 segment of anterior cerebral artery and anterior communicating artery aneurysms

    Institute of Scientific and Technical Information of China (English)

    冯文峰

    2013-01-01

    Objective To improve the predictability of surgical clipping and guide the steam shaping of microcatheters in endovascular embolization by analyzing the association of morphological features of A1 segment of anterior cerebral artery(ACA) with formation and classification of anterior

  6. Anterior tension band plating for anterior tibial stress fractures in high-performance female athletes - A report of 4 cases

    NARCIS (Netherlands)

    O. Borens; M.K. Sen; R.C. Huang; J. Richmond; P. Kloen; J.B. Jupiter; D.L. Helfet

    2006-01-01

    Stress fracture of the anterior tibial cortex is an extremely challenging fracture to treat, especially in the high-performance female athlete who requires rapid return to competition. Previous reports have not addressed treating these fractures in the world-class athlete with anterior plating. We h

  7. Selective visual attention to emotional words: Early parallel frontal and visual activations followed by interactive effects in visual cortex.

    Science.gov (United States)

    Schindler, Sebastian; Kissler, Johanna

    2016-10-01

    Human brains spontaneously differentiate between various emotional and neutral stimuli, including written words whose emotional quality is symbolic. In the electroencephalogram (EEG), emotional-neutral processing differences are typically reflected in the early posterior negativity (EPN, 200-300 ms) and the late positive potential (LPP, 400-700 ms). These components are also enlarged by task-driven visual attention, supporting the assumption that emotional content naturally drives attention. Still, the spatio-temporal dynamics of interactions between emotional stimulus content and task-driven attention remain to be specified. Here, we examine this issue in visual word processing. Participants attended to negative, neutral, or positive nouns while high-density EEG was recorded. Emotional content and top-down attention both amplified the EPN component in parallel. On the LPP, by contrast, emotion and attention interacted: Explicit attention to emotional words led to a substantially larger amplitude increase than did explicit attention to neutral words. Source analysis revealed early parallel effects of emotion and attention in bilateral visual cortex and a later interaction of both in right visual cortex. Distinct effects of attention were found in inferior, middle and superior frontal, paracentral, and parietal areas, as well as in the anterior cingulate cortex (ACC). Results specify separate and shared mechanisms of emotion and attention at distinct processing stages. Hum Brain Mapp 37:3575-3587, 2016. © 2016 Wiley Periodicals, Inc.

  8. More Than Meets the Eye: The Merging of Perceptual and Conceptual Knowledge in the Anterior Temporal Face Area

    Science.gov (United States)

    Collins, Jessica A.; Koski, Jessica E.; Olson, Ingrid R.

    2016-01-01

    An emerging body of research has supported the existence of a small face sensitive region in the ventral anterior temporal lobe (ATL), referred to here as the “anterior temporal face area”. The contribution of this region in the greater face-processing network remains poorly understood. The goal of the present study was to test the relative sensitivity of this region to perceptual as well as conceptual information about people and objects. We contrasted the sensitivity of this region to that of two highly-studied face-sensitive regions, the fusiform face area (FFA) and the occipital face area (OFA), as well as a control region in early visual cortex (EVC). Our findings revealed that multivoxel activity patterns in the anterior temporal face area contain information about facial identity, as well as conceptual attributes such as one’s occupation. The sensitivity of this region to the conceptual attributes of people was greater than that of posterior face processing regions. In addition, the anterior temporal face area overlaps with voxels that contain information about the conceptual attributes of concrete objects, supporting a generalized role of the ventral ATLs in the identification and conceptual processing of multiple stimulus classes. PMID:27199711

  9. Distance modulation of neural activity in the visual cortex.

    Science.gov (United States)

    Dobbins, A C; Jeo, R M; Fiser, J; Allman, J M

    1998-07-24

    Humans use distance information to scale the size of objects. Earlier studies demonstrated changes in neural response as a function of gaze direction and gaze distance in the dorsal visual cortical pathway to parietal cortex. These findings have been interpreted as evidence of the parietal pathway's role in spatial representation. Here, distance-dependent changes in neural response were also found to be common in neurons in the ventral pathway leading to inferotemporal cortex of monkeys. This result implies that the information necessary for object and spatial scaling is common to all visual cortical areas.

  10. Catarata polar anterior piramidal deslocada para a câmara anterior causando edema de córnea: relato de caso Corneal edema caused by a pyramidal anterior polar cataract dislocated to the anterior chamber: case report

    Directory of Open Access Journals (Sweden)

    Ramon Coral Ghanem

    2004-08-01

    Full Text Available Cataratas polares anteriores piramidais são opacidades cônicas que se projetam para a câmara anterior a partir da cápsula anterior do cristalino. Na grande maioria dos pacientes a opacidade permanece aderida e estável durante toda a vida. O objetivo deste trabalho é documentar uma manifestação incomum desse tipo de catarata: a deiscência espontânea das pirâmides para a câmara anterior causando descompensação endotelial e edema corneal bilateral. Relatamos o caso de uma paciente feminina, de 66 anos, branca, que apresentava edema corneal localizado inferiormente no olho direito associado à lesão nodular branco-esclerótica compatível com a pirâmide anterior da catarata polar. O olho esquerdo apresentava edema corneal difuso intenso e presença de uma catarata polar anterior com a região piramidal deslocada para a câmara anterior. Sabe-se que a pirâmide anterior pode permanecer inabsorvida na câmara anterior por longo período, pois é composta de tecido colágeno denso. Isto causa perda endotelial progressiva e edema corneal e deve ser considerada indicação de remoção cirúrgica da catarata polar anterior e de seu fragmento. Ressalta-se, também, a importância do bom senso no julgamento das cataratas polares anteriores, considerando-se tamanho da opacidade, simetria das opacidades e componente cortical associado, na tentativa de se evitar ambliopia.Pyramidal anterior polar cataracts are conical opacities that project into the anterior chamber from the anterior capsule of the lens. In the vast majority of patients the opacity remains bound and stable throughout life. We report an unusual complication of this type of cataract: spontaneous dehiscence of the pyramids to the anterior chamber causing bilateral endothelial damage and corneal edema. 66-year-old white woman presented with inferior corneal edema in the right eye and diffuse corneal edema in the left eye. A white nodular lesion was observed in the inferior angle

  11. Universal visualization platform

    Science.gov (United States)

    Gee, Alexander G.; Li, Hongli; Yu, Min; Smrtic, Mary Beth; Cvek, Urska; Goodell, Howie; Gupta, Vivek; Lawrence, Christine; Zhou, Jainping; Chiang, Chih-Hung; Grinstein, Georges G.

    2005-03-01

    Although there are a number of visualization systems to choose from when analyzing data, only a few of these allow for the integration of other visualization and analysis techniques. There are even fewer visualization toolkits and frameworks from which one can develop ones own visualization applications. Even within the research community, scientists either use what they can from the available tools or start from scratch to define a program in which they are able to develop new or modified visualization techniques and analysis algorithms. Presented here is a new general-purpose platform for constructing numerous visualization and analysis applications. The focus of this system is the design and experimentation of new techniques, and where the sharing of and integration with other tools becomes second nature. Moreover, this platform supports multiple large data sets, and the recording and visualizing of user sessions. Here we introduce the Universal Visualization Platform (UVP) as a modern data visualization and analysis system.

  12. Role of Scrib and Dlg in anterior-posterior patterning of the follicular epithelium during Drosophila oogenesis

    Directory of Open Access Journals (Sweden)

    Yu Lingzhu

    2009-12-01

    Full Text Available Abstract Background Proper patterning of the follicle cell epithelium over the egg chamber is essential for the Drosophila egg development. Differentiation of the epithelium into several distinct cell types along the anterior-posterior axis requires coordinated activities of multiple signaling pathways. Previously, we reported that lethal(2giant larvae (lgl, a Drosophila tumor suppressor gene, is required in the follicle cells for the posterior follicle cell (PFC fate induction at mid-oogenesis. Here we explore the role of another two tumor suppressor genes, scribble (scrib and discs large (dlg, in the epithelial patterning. Results We found that removal of scrib or dlg function from the follicle cells at posterior terminal of the egg chamber causes a complete loss of the PFC fate. Aberrant specification and differentiation of the PFCs in the mosaic clones can be ascribed to defects in coordinated activation of the EGFR, JAK and Notch signaling pathways in the multilayered cells. Meanwhile, the clonal analysis revealed that loss-of-function mutations in scrib/dlg at the anterior domains result in a partially penetrant phenotype of defective induction of the stretched and centripetal cell fate, whereas specification of the border cell fate can still occur in the most anterior region of the mutant clones. Further, we showed that scrib genetically interacts with dlg in regulating posterior patterning of the epithelium. Conclusion In this study we provide evidence that scrib and dlg function differentially in anterior and posterior patterning of the follicular epithelium at oogenesis. Further genetic analysis indicates that scrib and dlg act in a common pathway to regulate PFC fate induction. This study may open another window for elucidating role of scrib/dlg in controlling epithelial polarity and cell proliferation during development.

  13. Visual callosal connections: role in visual processing in health and disease.

    Science.gov (United States)

    Bocci, Tommaso; Pietrasanta, Marta; Cerri, Chiara; Restani, Laura; Caleo, Matteo; Sartucci, Ferdinando

    2014-01-01

    Visual cortical areas in the two sides of the brain are interconnected by interhemispheric fibers passing through the splenium of the corpus callosum. In this review, we summarize data concerning the anatomical features of visual callosal connections, their roles in basic visual processing, and how their alterations contribute to visual deficits in different human neuropathologies. Splenial fibers represent a population of excitatory axons with varying diameters, which interconnect cortical columns with similar functional properties (i.e., same orientation selectivity) in the two hemispheres. Their branches activate simultaneously distinct iso-oriented columns in the contralateral hemisphere, thus mediating forms of stimulus-dependent interhemispheric synchronization. Callosal branches also make synapses onto GABAergic cells, resulting in an inhibitory modulation of visual processing that involves both iso-oriented and cross-oriented cortical networks. Interhemispheric inhibition appears to predominate at short latencies following callosal activation, whereas excitation becomes more robust with increasing delays. These callosal effects are dynamically adapted to the incoming visual activity, so that stimuli providing only weak afferent input are facilitated by callosal pathways, whereas strong visual input via the retinogeniculate pathway tends to be offset by transcallosal inhibition. We also review data highlighting the contribution of callosal input activity to maturation of visual function during early 'critical periods' in brain development and describe how interhemispheric transfer of visual information is rerouted in cases of callosal agenesis or following splenial damage. Finally, we provide an overview of alterations in splenium anatomy or function that may be at the basis of visual defects in several pathologic conditions.

  14. Interhemispheric Connections between the Primary Visual Cortical Areas via the Anterior Commissure in Human Callosal Agenesis

    OpenAIRE

    van Meer, Nathalie; Houtman, Anne C.; Van Schuerbeek, Peter; Vanderhasselt, Tim; Milleret, Chantal; ten Tusscher, Marcel P.

    2016-01-01

    Aim: In humans, images in the median plane of the head either fall on both nasal hemi-retinas or on both temporal hemi-retinas. Interhemispheric connections allow cortical cells to have receptive fields on opposite sides. The major interhemispheric connection, the corpus callosum, is implicated in central stereopsis and disparity detection in front of the fixation plane. Yet individuals with agenesis of the corpus callosum may show normal stereopsis and disparity vergence. We set out to study...

  15. Restoring primary