• MeSH
• biologické modely * MeSH
• statistika jako téma MeSH
• zrakové evokované potenciály * MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

PURPOSE: The pupil light reflex is considered to be a simple subcortical reflex. However, many studies have proven that patients with isolated occipital lesions with homonymous hemianopia show pupillary hemihypokinesia. Our hypothesis is that the afferent pupillary system consists of two pathways: one via intrinsically photosensitive retinal ganglion cells (ipRGCs), the other running through the normal RGCs via the visual cortex. The purpose of this study was to test the hypothesis of these two separate pupillomotor pathways. METHODS: 12 patients (59.1 ± 18.8 years) with homonymous hemianopia due to post-geniculate lesions of the visual pathway and 20 normal controls (58.6 ± 12.9 years) were examined using chromatic pupillography: stimulus intensity was 28 lx corneal illumination, stimulus duration was 4.0 s, and the stimulus wavelengths were 420 ± 20 nm (blue) and 605 ± 20 nm (red), respectively. The examined parameters were baseline pupil diameter, latency, and relative amplitudes (absolute amplitudes compared to baseline), measured at maximal constriction, at 3 s after stimulus onset, at stimulus offset, and at 3 s and 7 s after stimulus offset. RESULTS: The relative amplitudes for the red stimulus were significantly smaller for hemianopia patients compared to the normal controls [maximal constriction: 35.6 ± 5.9% (hemianopia) to 42.3 ± 5.7% (normal); p = 0.004; 3 s after stimulus onset: p = 0.004; stimulus offset: p = 0.001]. No significant differences in any parameter were found between the two groups using the blue stimulus. CONCLUSIONS: The results support the hypothesis that the ipRGC pathway is mainly subcortical, whereas a second, non-ipRGC pathway via the occipital cortex exists.

• Klíčová slova
• Dorsal midbrain, Homonymous hemianopia, Intrinsically photosensitive retinal ganglion cells, Pupil light reflex, Pupillary hemihypokinesia, Visual cortex,
• MeSH
• diagnostické techniky oftalmologické * MeSH
• dospělí MeSH
• hemianopsie diagnóza   etiologie   patofyziologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• mezencefalon diagnostické zobrazování   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• nemoci mozku komplikace   diagnóza   MeSH
• počítačová rentgenová tomografie MeSH
• pupila fyziologie   MeSH
• reflex pupilární fyziologie   MeSH
• reprodukovatelnost výsledků MeSH
• retinální gangliové buňky fyziologie   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• světelná stimulace MeSH
• zraková pole fyziologie   MeSH
• zrakové korové centrum diagnostické zobrazování   patofyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Autodesk Animator software offers the suitable technique for visual stimulation in the registration of visual evoked responses (VERs). However, it is not possible to generate pulses that are synchronous with the animated sequences on any output port of the computer. These pulses are necessary for the synchronization of the computer that makes the registration of the VERs. The principle of the circuit is presented that is able to provide the synchronization of the analyzer with the stimulation computer using Autodesk Animator software.

• MeSH
• lidé MeSH
• počítačová grafika * MeSH
• světelná stimulace MeSH
• zrakové evokované potenciály * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

We describe a cheap, simple, portable and efficient approach to visual stimulation for neurophysiology which does not need any special hardware equipment. The method based on an animation technique uses the FLI autodesk animator format. This form of the animation is replayed by a special program ('player') providing synchronisation pulses toward recording system via parallel port. The 'player is running on an IBM compatible personal computer under MS-DOS operation system and stimulus is displayed on a VGA computer monitor. Various stimuli created with this technique for visual evoked potentials (VEPs) are presented.

• MeSH
• barva MeSH
• diagnóza počítačová metody   MeSH
• lidé MeSH
• mikropočítače * MeSH
• počítačová grafika * MeSH
• reprodukovatelnost výsledků MeSH
• světelná stimulace přístrojové vybavení   metody   MeSH
• validace softwaru * MeSH
• zrakové evokované potenciály * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

PURPOSE: To correlate the analysis of the optic nerve head (ONH) obtained with Disc Damage Likelihood Scale (DDLS), Heidelberg Retina Tomograph II (HRT II), and visual field (VF) parameters (Aulhorn scale, mean deviation [MD], and pattern standard deviation [PSD]) in patients with glaucoma. METHODS: Sixty-five eyes were evaluated using the DDLS classification. Fifty-seven eyes had stable primary open-angle glaucoma (POAG) and eight eyes were normal (control group). Classification of the ONH was performed using the HRT II, with Moorfields Regression Analysis (MRA) and Cup Shape Measure (CSM) indexes. The VF was examined by Full Threshold test (30-2) using the Humphrey Field Analyzer (HFA) perimeter and evaluated by three METHODS: Aulhorn's scale of 0 to 6, and two global indices, MD and PSD. RESULTS: The amount of ONH damage as estimated by the DDLS correlated well with topographic damage determined by HRT II (r=0.923 with MRA and r=0.807 with CSM) and with visual field loss as measured by the MD (r=-0.792) and PSD (r=0.718) of the HFA and Aulhorn field staging system (r=0.849). CONCLUSIONS: This study shows that evaluation of the ONH using the DDLS provides information that correlates well with VF and with data obtained from HRT II.

• MeSH
• diagnostické techniky oftalmologické MeSH
• discus nervi optici patologie   MeSH
• dospělí MeSH
• glaukom s otevřeným úhlem diagnóza   MeSH
• lidé středního věku MeSH
• lidé MeSH
• nemoci zrakového nervu diagnóza   MeSH
• nitrooční tlak MeSH
• poruchy zraku diagnóza   MeSH
• pravděpodobnostní funkce MeSH
• regresní analýza MeSH
• senioři MeSH
• testy zrakového pole MeSH
• tomografie metody   MeSH
• tonometrie oční MeSH
• zraková ostrost MeSH
• zraková pole * MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• elektroencefalografie MeSH
• evokované potenciály * MeSH
• habituace (psychofyziologie) MeSH
• králíci MeSH
• mozkový kmen fyziologie   chirurgie   MeSH
• počítače MeSH
• stereotaktické techniky MeSH
• světlo * MeSH
• zrakové korové centrum fyziologie   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

CONTEXT: Visual disturbances due to the toxic effect of formic acid in acute methanol poisonings are generally transient. The subjective symptoms of visual toxicity may resolve within few weeks and fundoscopic signs of acute optic neuropathy subside within 1-2 months; therefore, the prevalence of long-term visual sequelae in the population of survivors of poisonings may be underestimated. OBJECTIVE: To study the prevalence and character of long-term visual sequelae of acute methanol poisonings based on the data from the Czech mass methanol outbreak in 2012. PATIENTS AND METHODS: A total of 50 patients with confirmed methanol poisoning were included in this longitudinal cross-sectional study, median age: 48 (range, 23-73) years. The following tests were performed: optical coherence tomography or OCT with evaluation of the retinal nerve fibers layer (RNFL), visual evoked potentials (VEP), magnetic resonance imaging (MRI) of brain, complete ocular examination (visual acuity/field, color vision, contrast sensitivity, and fundus), neurological examinations, and biochemical tests. RESULTS: Of 50 patients, 7/50 (14%) were discharged with diagnosed visual sequelae and 6/50 (12%) were discharged with both visual and central nervous system sequelae of poisoning. On the follow-up examination, 20/50 (40%) of the patients had long-term visual sequelae, with 8% of blindness. A total of 38% of the patients had abnormal (28% borderline) findings on RNFL, and 40% had abnormal (18% borderline) VEP. Among the patients discharged without detected visual sequelae, 8/37 (22%) had abnormal RNFL and VEP. Patients with visual sequelae had brain lesions more often (70% vs. 27%, p < 0.01). MRI identified optic nerve lesions in 2/20 cases with abnormal VEP only. The groups with and without visual sequelae differed in serum methanol, ethanol, HCO3-, formate, pH, anion gap, and base deficit (all p < 0.01). Visual disturbances on admission and coma were more prevalent in the patients with visual sequelae (p < 0.05). Patients with positive serum ethanol on admission were 93% less likely to have optical axonal damage (OR: 0.07 (95% CI: 0.01-0.8); p < 0.05). No association was found between visual sequelae and type of antidote administered, mode of hemodialysis, or folate substitution. Pre-hospital administration of ethanol seemed beneficial: these patients were 90% less likely to have abnormal RNFL findings (OR: 0.10 (95% CI: 0.02-0.52); p < 0.01). CONCLUSIONS: The long-term visual sequelae were clearly underestimated on discharge, suggesting a significantly higher amount of patients with long-term sequelae than earlier reported. Thorough examinations before discharge and during follow-up will likely uncover a higher morbidity also after methanol poisonings in general.

• Klíčová slova
• acute methanol poisoning, health sequelae of poisoning, hospital treatment, long-term visual damage, treatment outcome,
• MeSH
• akutní nemoc MeSH
• bazální ganglia účinky léků   patofyziologie   MeSH
• časové faktory MeSH
• diagnostické techniky oftalmologické MeSH
• dospělí MeSH
• epidemický výskyt choroby * MeSH
• hodnocení rizik MeSH
• lidé středního věku MeSH
• lidé MeSH
• lineární modely MeSH
• logistické modely MeSH
• longitudinální studie MeSH
• methanol otrava   MeSH
• mladý dospělý MeSH
• multivariační analýza MeSH
• nervus opticus účinky léků   patofyziologie   MeSH
• obnova funkce MeSH
• ochranné faktory MeSH
• odds ratio MeSH
• otrava diagnóza   epidemiologie   patofyziologie   terapie   MeSH
• poruchy zraku chemicky indukované   diagnóza   epidemiologie   patofyziologie   terapie   MeSH
• prediktivní hodnota testů MeSH
• prevalence MeSH
• průřezové studie MeSH
• retina účinky léků   patofyziologie   MeSH
• rizikové faktory MeSH
• rozdělení chí kvadrát MeSH
• senioři MeSH
• výsledek terapie MeSH
• zrak účinky léků   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Názvy látek
• methanol MeSH

Visual evoked potentials to motion-onset stimulation (M-VEPs) gradually attenuate in amplitude during examination. The observed decline in averaged responses can be caused by decreases in single response magnitudes and/or increased variability in a response delays, that is, latency jittering. To illuminate the origins of the suppression of M-VEPs during stimuli repetition, we used correlation technique to estimate an upper bound of possible latency jittering of single sweeps and we evaluated the effect of its correction on the amplitudes of three M-VEP dominant peaks P1, N2 and P3. During prolonged visual motion stimulation, the variability of corrective latency shifts in the occipital region increased (r = 0.35: 0.44) and the number of single responses corresponding to the average curve declined in occipital and parietal derivations (r = -0.48: -0.62). While the P1 peak amplitude did not exhibit any time-specific behaviour, the N2 amplitude exhibited a significant decay of 29.4% that was partially reduced to 16.6% in the central occipital derivation by the latency jitter and non-correspondence corrections. The strongest attenuation (32.7%) was observed in the P3 amplitude and was less sensitive to the corrections, dropping only to 27.9%. The main part of the response suppression to repeated motion stimulation was caused by amplitude drop and represents non-stationary process that likely correspond to a fatigue model. The rise of variability in latency jitter correction and the reduction in single responses correlated with the M-VEP were significant factors associated with prolonged motion stimulation. The relation of these parameters to a hypothetical veridical response is ambiguous and can be caused by a time shift of the response or by a change of signal-to-noise ratio. Using selective averaging and latency jitter correction, the effect of response suppression was partially removed.

• MeSH
• adaptace oční fyziologie   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• rozpoznávání obrazu fyziologie   MeSH
• vnímání pohybu fyziologie   MeSH
• zrakové evokované potenciály fyziologie   MeSH
• zrakové korové centrum fyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The term homonymous hemianopia refers to visual impairment due to a post-chiasmatic brain lesion. Mammalian neurons of the central nervous system do not have the ability to regenerate. However, the cerebral cortex shows plasticity in certain cases. Motor or speech disorders due to frontal lobe brain damage can be improved with well-directed rehabilitation techniques. If such plasticity is possible, it raises the question whether specialized training could improve a cortical visual disorder. There is need for simple visual training which could be used in rehabilitation. A few different approaches have been developed to treat patients with hemianopia: (1) substitution including special devices, such as optical prisms; (2) compensation using intact residual abilities - especially training of eye movements; (3) restitution which is based on stimulating the blind hemifield. The third method of rehabilitation is the most controversial; however, it has the largest potential. To support concepts of the targeted rehabilitation outlined here, first: further development of the theory of plasticity in visual pathways is required and second: the efficacy of the rehabilitation procedures has to be demonstrated by clinical evidence. We review methods and approaches of hemianopia rehabilitation and treatment. We also review results of contemporary clinical studies and meta-studies.

• MeSH
• cévní mozková příhoda komplikace   MeSH
• hemianopsie etiologie   rehabilitace   MeSH
• lidé MeSH
• obnova funkce fyziologie   MeSH
• techniky fyzikální terapie * MeSH
• zraková pole fyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Visual acuity, the ability to discern static spatial details, is crucial for understanding how organisms perceive their environment. Lacertid lizards are diurnal, feed on small prey, and communicate using multiple visual signals, including postures, dynamic displays and conspicuous colour patches. However, their visual acuity remains unstudied, leaving a critical gap in our understanding of their visual capabilities. Visual acuity is often estimated behaviourally using an optomotor apparatus, which quantifies a reflex-orienting movement called the optomotor response (OMR), or histologically by evaluating retinal ganglion cell (RGC) densities. We combined these two techniques to estimate visual acuity in a lacertid lizard, Podarcis muralis. OMR assays estimated an acuity of 2.05 cpd, while RGC counts revealed a peak density (>7000 cells mm-2) within the area centralis, corresponding to 1.56 cpd. RGC topographic maps revealed additional areas of high cell density in the dorso-nasal and dorso-temporal regions, while the area centralis was located slightly ventrally in the centro-temporal retina. This RGC distribution suggests adaptations to resolve stimuli in the centre and lower parts of the lizard's visual field, which may enhance predator and prey detection on the ground. Using our estimated acuities, we calculated that a lizard can detect a conspecific from 10 m and a 2 mm-long object from 40 cm away. In addition, we generated AcuityView images (R package) showing how this species might discern conspecific colour patches at different distances. These images suggest that beyond 10 cm, the surroundings become increasingly blurred, suggesting a role for static visual signals specifically in close-range communication.

• Klíčová slova
• Eye, Optomotor apparatus, Retinal ganglion cell, Spatial resolution, Vision, Visual signal,
• MeSH
• ještěři * fyziologie   MeSH
• retinální gangliové buňky fyziologie   MeSH
• zraková ostrost * fyziologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH