Historical aspects and current views of the etiopathogenesis and clinical manifestations of optic nerve pits

Optic nerve pits are a mono- or bilateral congenital anomaly represented by optic disc depressions of various sizes. In half of the cases, the pits are complicated by edema, central retinal detachment and retinoschisis, and cause visual function decrease. Visual acuity losses can be either insignificant or pronounced. Optic discs pits have been investigated massively over the last century and a half, but their etiology is still underresearched. In recent years, however, due to the development of digital scanning and data processing technologies and the emergence of non-invasive highly informative diagnostic methods, it has become possible to reveal structural and functional changes of the optic disc in vivo, in addition to the traditional detection of histological changes in cadaveric eyes.Glaucomatous process modeling is one of the challenges in ophthalmology. And this is due primarily to the fact that, so far, the main reasons for the onset and progression of glaucoma. Numerous works on experimental research in its core model ocular. However, there are forms of glaucoma, which are independent of the level of intraocular pressure. Ideal model of glaucoma is considered a model with the development of the characteristic symptom in which a key symptom is a slowly progressive excavation of the optic nerve. But given the new knowledge in the pathogenesis of neurodegenerative changes in glaucoma in this model should be added and the opportunity to study the brain, vascular factors of progression, the level of neurotransmitters, trophic factors, etc. Therefore, we tried to make the analysis of models of glaucoma in various experimental animals and determine the most appropriate model for studying the pathogenesis of glaucoma.

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INFLUENCE OF OPTIC NERVE DRUSEN ON VISUAL FUNCTIONS IN CHILDREN AND ADOLESCENTS WITH ESSENTIAL ARTERIAL HYPERTENSION

Бюллетень Восточно-Сибирского научного центра Сибирского отделения Российской академии медицинских наук ◽

10.12737/23797 ◽

2016 ◽

Vol 1 (6) ◽

pp. 148-152

Author(s):

Савина ◽

Yuliya Savina ◽

Юрьева ◽

Tatyana Yureva ◽

Щуко ◽

...

Keyword(s):

Optic Nerve ◽

Optic Disc ◽

Clinical Manifestations ◽

Family Health ◽

Vascular Wall ◽

Primary Hypertension ◽

Clinical Electrophysiology ◽

Functional Changes ◽

Male Adolescents ◽

Optic Disc Drusen

The article presents data examination of children and male adolescents, aged 8 to 17years without eye pathologies, with primary hypertension diagnosis – established at the clinic of Scientific Centre for Family Health and Human Re-production Problems. Examination results were: 42patients (84eyes) had primary hypertension with optic disc drusen, 8patients (16eyes) had primary hypertension without optic disc drusen.Characteristics of basic functional changes of patients ophthalmic status with and without optic disc drusen on the basis of data of visometry refractometry, keratometry, computer perimetry, ultrasonic ehobiometry. Doppler angio-graphic examination of ocular vessels, electroretinography (ERG) according to registration standards proposed by the International Society of Clinical electrophysiology of (ISCEV), visual-evoked potentials (VEP), biomicroscopy of the eye, fundus photo registration.To verify and differentiate the prominence of the optic disc drusen in cases of the prominence of stagnant disc with characteristic extension of perineural space, all patients underwent an ultrasound scan procedure of the eyeball. The study obtained data on early pre-clinical manifestations of hypertensive angiohorioretinopaty.The risk factors for the formation of drusen of the optic nerve were identified. We determined that the presence of drusen does not lead to the aggravation of the changes of the visual system, formed under the influence of high blood pressure, affecting only the indicators characterizing ischemic processes in the retina and the optic nerve, which is due to the influence of compression of drusen on glial tissue and the vascular wall.

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Study of Osteocyte Behavior by High-Resolution Intravital Imaging Following Photo-Induced Ischemia

Molecules ◽

10.3390/molecules23112874 ◽

2018 ◽

Vol 23 (11) ◽

pp. 2874

Author(s):

Hengfeng Yuan ◽

Wen Jiang ◽

Yuanxin Chen ◽

Betty Kim

Keyword(s):

Imaging Techniques ◽

Avascular Osteonecrosis ◽

Functional Changes ◽

Cellular Processes ◽

Non Invasive ◽

Behavioral Dynamics ◽

Bony Anatomy ◽

Magnetic Resonance Imaging Mri

Ischemic injuries and local hypoxia can result in osteocytes dysfunction and play a key role in the pathogenesis of avascular osteonecrosis. Conventional imaging techniques including magnetic resonance imaging (MRI) and computed tomography (CT) can reveal structural and functional changes within bony anatomy; however, characterization of osteocyte behavioral dynamics in the setting of osteonecrosis at the single cell resolution is limited. Here, we demonstrate an optical approach to study real-time osteocyte functions in vivo. Using nicotinamide adenine dinucleotide (NADH) as a biomarker for metabolic dynamics in osteocytes, we showed that NADH level within osteocytes transiently increase significantly after local ischemia through non-invasive photo-induced thrombosis of afferent arterioles followed by a steady decline. Our study presents a non-invasive optical approach to study osteocyte behavior through the modulation of local environmental conditions. Thus it provides a powerful toolkit to study cellular processes involved in bone pathologies in vivo.

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Is a virtual clinic model a safe and effective way for assessing patients referred with suspiciously blurred optic discs? The blurred disc clinic

European Journal of Ophthalmology ◽

10.1177/1120672120976043 ◽

2020 ◽

pp. 112067212097604

Author(s):

Joanna M Jefferis ◽

Nigel Griffith ◽

Daniel Blackwell ◽

Ruth Batty ◽

Simon J Hickman ◽

...

Keyword(s):

Optic Nerve ◽

Optic Disc ◽

Direct Contact ◽

Visual Fields ◽

Referral Letter ◽

Face To Face ◽

The Face ◽

Optic Discs ◽

Eye Clinic ◽

Virtual Clinic

Background: There are increasing numbers of referrals to ophthalmology departments due to blurred optic disc margins. In light of this and the COVID-19 pandemic we aimed to assess whether these patients could be safely assessed without direct contact between the clinician and patient. Methods: We retrospectively reviewed the records of consecutive patients seen in our ‘blurred disc clinic’ between August 2018 and October 2019. We then presented anonymous information from their referral letter, their visual fields and optic nerve images to two consultant neuro-ophthalmologists blinded to the outcome of the face-to-face consultation. In the simulated virtual clinic, the two consultants were asked to choose an outcome for each patient from discharge, investigate or bring in for a face-to-face assessment. Results: Out of 133 patients seen in the blurred disc clinic, six (4.5%) were found to have papilloedema. All six were identified by both neuro-ophthalmologists as needing a face-to-face clinic consultation from the simulated virtual clinic. One hundred and twenty (90%) patients were discharged from the face-to-face clinic at the first consultation. The two neuro-ophthalmologists chose to discharge 114 (95%) and 99 (83%) of these respectively from the simulated virtual clinic. The virtual clinic would have potentially missed serious pathology in only one patient who had normal optic discs but reported diplopia at the previous face-to-face consultation. Conclusions: A virtual clinic model is an effective way of screening for papilloedema in patients referred to the eye clinic with suspicious optic discs. Unrelated or incidental pathology may be missed in a virtual clinic.

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Hyperspectral imaging of retinal microvascular anatomy

Journal of Biomedical Engineering and Informatics ◽

10.5430/jbei.v2n1p139 ◽

2015 ◽

Vol 2 (1) ◽

pp. 139 ◽

Cited By ~ 2

Author(s):

Amir H. Kashani ◽

Mark Wong ◽

Nicole Koulisis ◽

Chein-I Chang ◽

Gabriel Martin ◽

...

Keyword(s):

Hyperspectral Image ◽

Model Organism ◽

Science Research ◽

Tomographic Imaging ◽

Diagnostic Methods ◽

Camera System ◽

Computed Tomographic ◽

Non Invasive ◽

Computed Tomographic Imaging

Background: Hyperspectral image processing has been applied to many aspects of astronomical and earth science research. Furthermore, advances in computed tomographic imaging spectroscopy and diffraction grating design have allowed biological applications for non-invasive tissue analysis. Herein, we describe a hyperspectral computed tomographic imaging spectroscope (HCTIS) that provides high spatial, spectral and temporal resolution ideal for imaging biological tissue in vivo. Methods: We demonstrate proof-of-principle application of the HCTIS by imaging and mapping the microvascular anatomy of the retina of a model organism (rabbit) in vivo. The imaging procedure allows rapid and dense spectral sampling, is non-toxic, non-invasive, and easily adaptable to a commercially available fundus camera system. Results: HCTIS provides highly co-registered temporal, spatial and spectral data with resolution capable of reconstructing the fine vascular tree of the rabbit retina in vivo. Conclusions: We show that HCTIS allows for reliable and reproducible tissue classification and detection using signature discriminant analysis. Future applications of this system may provide promising diagnostic methods for diseases of many tissues.

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Extracranial Carotid Artery Disease Assessed By Indium-111 Labelled Platelets In Man

10.1055/s-0038-1652551 ◽

1981 ◽

Author(s):

M Goldman ◽

D Simpson ◽

R J Hawker ◽

Z Drolc ◽

C N McCollum

Keyword(s):

Gamma Camera ◽

Ex Vivo ◽

Carotid Artery Disease ◽

Objective Assessment ◽

Diagnostic Methods ◽

Invasive Technique ◽

Platelet Activity ◽

Transient Ischaemic Attacks ◽

Non Invasive

Platelet microemboli have been implicated in the aetiology of transient ischaemic attacks and strokes. Current non-invasive diagnostic methods are restricted to assessing blood flow. Arteriography may demonstrate non-occluding atheromatous ulcers but carries a significant morbidity.111-In labelled platelets and gamma camera imaging of diseased carotid vessels have therefore been evaluated.Eight patients proceeding to unilateral carotid endarterectomy received an injection of autologous platelets labelled with 111-In-oxine 48 hours preoperatively. Gamma camera images were taken at 4 and 24 hours. Operative endarterectomy specimens were collected and gamma emissions were measured.The scintigraphic images were independently assessed by two observers. Nine abnormal vessels were identified by platelet accumulation. In 5 cases the observers combined assessment was in complete accord with previous bilateral angiography. Individually each observer identified the symptomatic side in 6 patients. Activity in the endarterectomy specimens measured ex vivo varied from 1.22-84.5 times greater than background activity. The ratio of specimen activity to 5 ml blood samples simultaneously taken varied from 0.017 to 0.360 (mean 0.089).This non-invasive technique allows localisation of platelet activity in the extracranial cerebral circulation. Objective assessment in vivo is hindered by the relatively small amount of activity on the diseased vessels by comparison with circulating blood activity.

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Neuroimaging Advances in Stroke Rehabilitation

European Neurological Review ◽

10.17925/enr.2010.05.02.67 ◽

2010 ◽

Vol 5 (2) ◽

pp. 67

Author(s):

Rüdiger J Seitz ◽

Robert Lindenberg ◽

Gottfried Schlaug ◽

◽

...

Keyword(s):

Diffusion Tensor ◽

Motor Impairment ◽

Motor Recovery ◽

Experimental Therapy ◽

Functional Changes ◽

Non Invasive ◽

Functional Potential ◽

Recovery Mechanisms ◽

Therapy Studies

Human ischaemic stroke is a multistage disorder with various routes of recovery. Neuroimaging allows researchers to explore the pathophysiology and recovery mechanismsin vivo. Based on these findings, motor recovery and chronic motor impairment after stroke have been linked to structural alterations of grey and white matter as well as functional changes in the perilesional tissue. Parameters derived from diffusion tensor imaging and functional magnetic resonance imaging can be used as surrogate markers of chronic motor impairment and predictors of functional potential for motor recovery. These parameters have the potential to tailor individual rehabilitation and stratify patients for experimental therapy studies such as invasive and non-invasive brain stimulation alone or in combination with other facilitators.

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Neuroimaging Advances in Stroke Rehabilitation

US Neurology ◽

10.17925/usn.2010.06.02.105 ◽

2010 ◽

Vol 06 (02) ◽

pp. 105 ◽

Cited By ~ 1

Author(s):

Rüdiger J Seitz ◽

Robert Lindenberg ◽

Gottfried Schlaug ◽

◽

...

Keyword(s):

Diffusion Tensor ◽

Motor Impairment ◽

Motor Recovery ◽

Experimental Therapy ◽

Functional Changes ◽

Non Invasive ◽

Functional Potential ◽

Recovery Mechanisms ◽

Therapy Studies

Human ischemic stroke is a multistage disorder with various routes of recovery. Neuroimaging allows researchers to explore the pathophysiology and recovery mechanismsin vivo. Based on these findings, motor recovery and chronic motor impairment after stroke have been linked to structural alterations of grey and white matter as well as functional changes in the perilesional tissue. Parameters derived from diffusion tensor imaging and functional magnetic resonance imaging can be used as surrogate markers of chronic motor impairment and predictors of functional potential for motor recovery. These parameters have the potential to tailor individual rehabilitation and stratify patients for experimental therapy studies such as invasive and non-invasive brain stimulation alone or in combination with other facilitators.

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Reversible membrane reorganizations during photosynthesis in vivo: revealed by small-angle neutron scattering

Biochemical Journal ◽

10.1042/bj20110180 ◽

2011 ◽

Vol 436 (2) ◽

pp. 225-230 ◽

Cited By ~ 50

Author(s):

Gergely Nagy ◽

Dorthe Posselt ◽

László Kovács ◽

Jens K. Holm ◽

Milán Szabó ◽

...

Keyword(s):

Neutron Scattering ◽

Small Angle ◽

Small Angle Neutron Scattering ◽

Higher Plants ◽

Thylakoid Membranes ◽

Invasive Technique ◽

Time Resolved ◽

Functional Changes ◽

Non Invasive

In the present study, we determined characteristic repeat distances of the photosynthetic membranes in living cyanobacterial and eukaryotic algal cells, and in intact thylakoid membranes isolated from higher plants with time-resolved small-angle neutron scattering. This non-invasive technique reveals light-induced reversible reorganizations in the seconds-to-minutes time scale, which appear to be associated with functional changes in vivo.

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Assessment of the effect of long-term continuous stay in the artificial hypoxic gas-air environment at normal atmospheric pressure on the functional state of the cardiovascular system

Reviews on Clinical Pharmacology and Drug Therapy ◽

10.17816/rcf16347-53 ◽

2018 ◽

Vol 16 (3) ◽

pp. 47-53

Author(s):

Andrei V. Lyubimov ◽

Andrei O. Ivanov ◽

Eduard N. Bezkishkii ◽

Pavel G. Shakhnovich ◽

Dmitrii V. Cherkashin

Keyword(s):

Cardiovascular System ◽

Atmospheric Pressure ◽

Clinical Manifestations ◽

The Body ◽

Diagnostic Methods ◽

Continuous Exposure ◽

Functional Fitness ◽

Functional Changes ◽

Normal Atmospheric Pressure ◽

Hypoxic State

In the vast majority of clinical cases, hypoxia and hypoxia are considered as negative pathological processes that require urgent correction with subsequent pharmacological support for the restoration of functioning, and in some cases, the structure of the involved organ and system. The loss of full functionality as a result of local or general exposure to the hypoxia is confirmed by numerous studies. However, there are research data showing that subliminal exposure to hypoxia can be used as a positive adaptation factor, which increases the overall health of the body, stamina, and tolerance to physical load. This mechanism is actively used in training athletes of different levels of functional fitness, sports and ages. There is a question of balance of adaptive and damaging properties of hypoxia. Threshold values at which the hypoxic state will have positive adaptive or negative — damaging properties are not clearly defined at the moment. The key criterion for a hypoxic environment is the concentration of oxygen in the inhaled air. At the same time, physiological or pathophysiological response to changes in concentration is purely individual and primarily depends on the parameters of homeostasis. This issue is relevant because clinical manifestations characteristic of the hypoxic state develop in patients with different forms of coronary heart disease. The purpose of our study was an attempt to document the functional changes from the cardiovascular system of healthy individuals with prolonged continuous exposure to artificial hypoxic conditions while maintaining normal atmospheric pressure using standard diagnostic methods that are generally available.

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