Saúde alerta sobre a importância do diagnóstico precoce do retinoblastoma

Nesta quarta-feira (18), dia em que se lembra a importância do diagnóstico precoce do retinoblastoma, o Ministério da Saúde chama a atenção dos pais e responsáveis a ficarem atentos aos primeiros sinais da doença. O retinoblastoma é um tumor maligno originário das células da retina, que é a parte do olho responsável pela visão, afetando um ou ambos os olhos. É o mais comum tumor maligno intraocular da infância e geralmente ocorre antes dos 5 anos de idade. Pode ocorrer de forma esporádica (70 a 75% dos casos) ou hereditária (25 a 30% dos casos).

Plastic reorganization of the topological asymmetry of hemispheric white matter networks induced by congenital visual experience deprivation.

Congenital blindness offers a unique opportunity to investigate human brain plasticity. The influence of congenital visual loss on the asymmetry of the structural network remains poorly understood. To address this question, we recruited 21 participants with congenital blindness (CB) and 21 age-matched sighted controls (SCs). Employing diffusion and structural magnetic resonance imaging, we constructed hemispheric white matter (WM) networks using deterministic fiber tractography and applied graph theory methodologies to assess topological efficiency (i.e., network global efficiency, network local efficiency, and nodal local efficiency) within these networks. Statistical analyses revealed a consistent leftward asymmetry in global efficiency across both groups. However, a different pattern emerged in network local efficiency, with the CB group exhibiting a symmetric state, while the SC group showed a leftward asymmetry. Specifically, compared to the SC group, the CB group exhibited a decrease in local efficiency in the left hemisphere, which was caused by a reduction in the nodal properties of some key regions mainly distributed in the left occipital lobe. Furthermore, interhemispheric tracts connecting these key regions exhibited significant structural changes primarily in the splenium of the corpus callosum. This result confirms the initial observation that the reorganization in asymmetry of the WM network following congenital visual loss is associated with structural changes in the corpus callosum. These findings provide novel insights into the neuroplasticity and adaptability of the brain, particularly at the network level.

Perceiving depth beyond sight: Evaluating intrinsic and learned cues via a proof of concept sensory substitution method in the visually impaired and sighted.

This study explores spatial perception of depth by employing a novel proof of concept sensory substitution algorithm. The algorithm taps into existing cognitive scaffolds such as language and cross modal correspondences by naming objects in the scene while representing their elevation and depth by manipulation of the auditory properties for each axis. While the representation of verticality utilized a previously tested correspondence with pitch, the representation of depth employed an ecologically inspired manipulation, based on the loss of gain and filtration of higher frequency sounds over distance. The study, involving 40 participants, seven of which were blind (5) or visually impaired (2), investigates the intrinsicness of an ecologically inspired mapping of auditory cues for depth by comparing it to an interchanged condition where the mappings of the two axes are swapped. All participants successfully learned to use the algorithm following a very brief period of training, with the blind and visually impaired participants showing similar levels of success for learning to use the algorithm as did their sighted counterparts. A significant difference was found at baseline between the two conditions, indicating the intuitiveness of the original ecologically inspired mapping. Despite this, participants were able to achieve similar success rates following the training in both conditions. The findings indicate that both intrinsic and learned cues come into play with respect to depth perception. Moreover, they suggest that by employing perceptual learning, novel sensory mappings can be trained in adulthood. Regarding the blind and visually impaired, the results also support the convergence view, which claims that with training, their spatial abilities can converge with those of the sighted. Finally, we discuss how the algorithm can open new avenues for accessibility technologies, virtual reality, and other practical applications.

Vision loss and diabetic retinopathy prevalence and risk among a cohort of Indigenous and non-Indigenous Australians with type 2 diabetes receiving renal haemodialysis treatment: The retinopathy in people currently on renal dialysis (RiPCORD) study.

AIMS: Diabetic nephropathy, vision loss and diabetic retinopathy (DR) are frequent comorbidities among individuals with type 2 diabetes (T2D). The Retinopathy in People Currently On Renal Dialysis (RiPCORD) study sought to examine the epidemiology and risk of vision impairment (VI) and DR among a cohort of Indigenous and non-Indigenous Australians with T2D currently receiving haemodialysis for end-stage renal failure (ESRF). METHODS: A total of 106 Indigenous and 109 non-Indigenous Australians were recruited in RiPCORD across five haemodialysis centres in urban and remote settings. Clinical assessments, questionnaires and medical record data determined the rates of ocular complications and risk factor profiles. RESULTS: Prevalence rates include unilateral VI, 23.5 %; bilateral VI, 11.7 %; unilateral blindness, 14.2 %; and bilateral blindness, 3.7 %, with no significant differences between sub-cohorts (p=0.30). DR prevalence rates were 78.0 % among non-Indigenous Australians and 93.1 % among Indigenous Australians (p=<0.001). Non-Indigenous ethnicity (OR: 0.28) and pre-dialysis diastolic blood pressure (OR: 0.84 per 10-mmHg) were protective, while peripheral vascular disease (OR: 2.79) increased DR risk. CONCLUSIONS: Ocular complications among individuals with T2D and ESRF are disproportionately high, especially for Indigenous Australians, and beyond what can be accounted for by risk factor variation. Findings suggest a need to improve screening and preventative efforts within this high-risk population group.

Biodegradable polymers and platelet-rich plasma causing visual impairment: a literature review.

BACKGROUND: Dermal fillers are widely used for facial rejuvenation and esthetic enhancement, offering temporary solutions for aging and volume loss. Despite their general safety, a rare but severe complication associated with these fillers is visual impairment, including blindness. This underscores the need for a thorough understanding of risks associated with various filler materials. Historical cases of blindness following filler injections date back to 1963, with increasing reports linked to the expansion of the cosmetic filler industry. While hyaluronic acid (HA) and autologous fat have been extensively studied, other fillers such as calcium hydroxylapatite and poly-l-lactic acid (PLLA) are less understood. OBJECTIVE: This systematic review aims to address gaps in the literature by providing a comprehensive overview of visual impairment caused by fillers other than HA and autologous fat. We systematically examine the prevalence, causes, clinical features, and treatment outcomes associated with these less common fillers. MATERIALS AND METHODS: A comprehensive literature search was conducted across databases including PubMed, Scopus, and Google Scholar using terms related to visual impairment and dermal fillers. Studies published between 2014 and 2021, including observational studies and case reports, were included. Studies were selected based on predefined inclusion and exclusion criteria, and a PRISMA flow diagram was used to illustrate the study selection process. RESULTS: The review identifies and summarizes cases of visual impairment associated with calcium hydroxylapatite, poly-d,l-lactic acid (PDLLA), and PLLA fillers. Key findings reveal that visual impairment following these fillers is rare but can occur suddenly or within a few days of the procedure. Cases of delayed onset up to two weeks are also noted, emphasizing the need for extended post-procedure monitoring. DISCUSSION: The review highlights unique insights into the risks associated with non-HA fillers, such as the heightened risk in the periorbital region and other facial areas. It explores mechanisms of complications, including retrograde flow of emboli leading to retinal ischemia. The discussion also covers emergency protocols and preventative measures, providing valuable guidance for managing and mitigating risks. CONCLUSIONS: Visual impairment caused by fillers other than HA and autologous fat, while rare, represents a serious complication that requires careful attention. This review contributes new perspectives on the differential risks of various fillers, symptom onset variability, and anatomical risk factors. Emphasizing the importance of proper patient selection, technique, and monitoring, it calls for further research to better understand and prevent these complications, ultimately aiming for safer and more effective use of soft-tissue fillers.

Perception and satisfaction of blind individuals regarding an electronic cane prototype with a wearable haptic device.

PURPOSE: This study aimed to evaluate the perception and degree of satisfaction of blind individuals regarding an electronic cane prototype with a wearable haptic interface. METHODS: Two scenarios with different obstacles were created to conduct tests with the canes (the user's cane and the prototype one). The perception and satisfaction of participants regarding the electronic cane were assessed using a questionnaire, the number of collisions during the tests, and the time each individual took to complete the course in each scenario. RESULTS: Ten blind individuals who used the white cane participated in this study. Eight were males, and two were females. Their age ranged from 23 to 43 (average 32.3 ± 7.13 years and median 32 years). There was a tendency for fewer collisions with ground obstacles when the electronic cane was used than when the white cane was used. However, there was no statistically significant difference between the number of collisions and the course completion time in each scenario with either canes tested. CONCLUSION: Overall, the perception and satisfaction of individuals regarding the prototype used were positive.

Sudden transient blindness following ureteroscopy: an uncommon complication of a common procedure (a case report).

Perioperative vision loss following non-ophthalmic surgical procedures represents a rare but potentially serious complication. Although its occurrence in urology is infrequent, the consequences for patients and legal implications are significant. We present the case of a 53-year-old woman with no notable medical history, treated for renal lithiasis. Following the ureteroscopy, the patient experienced a sudden reduction in visual acuity. The diagnosis made was that of posterior ischemic optic neuropathy. This case illustrates a rare complication associated with ureteroscopy, highlighting the importance of increased awareness and rigorous postoperative monitoring, especially in patients with risk factors such as anemia or hypertension. Fortunately, the patient's rapid and complete recovery is encouraging, suggesting that early identification and appropriate management can lead to a favorable prognosis.

Postural control depends on early visual experience.

The present study investigated the role of early visual experience in the development of postural control (balance) and locomotion (gait). In a cross-sectional design, balance and gait were assessed in 59 participants (ages 7-43 years) with a history of (a) transient congenital blindness, (b) transient late-onset blindness, (c) permanent congenitally blindness, or (d) permanent late-onset blindness, as well as in normally sighted controls. Cataract-reversal participants who experienced a transient phase of blindness and gained sight through cataract removal surgery showed worse balance performance compared with sighted controls even when tested with eyes closed. Individuals with reversed congenital cataracts performed worse than individuals with reversed developmental (late emerging) cataracts. Balance performance in congenitally cataract-reversal participants when tested with eyes closed was not significantly different from that in permanently blind participants. In contrast, their gait parameters did not differ significantly from those of sighted controls. The present findings highlight both the need for visual calibration of proprioceptive and vestibular systems and the crossmodal adaptability of locomotor functions.

Motion's privilege in recognizing facial expressions following treatment for blindness.

In his 1872 monograph, Charles Darwin posited that "… the habit of expressing our feelings by certain movements, though now rendered innate, had been in some manner gradually acquired."1 Nearly 150 years later, researchers are still teasing apart innate versus experience-dependent contributions to expression recognition. Indeed, studies have shown that face detection is surprisingly resilient to early visual deprivation,2,3,4,5 pointing to plasticity that extends beyond dogmatic critical periods.6,7,8 However, it remains unclear whether such resilience extends to downstream processing, such as the ability to recognize facial expressions. The extent to which innate versus experience-dependent mechanisms contribute to this ability has yet to be fully explored.9,10,11,12,13 To investigate the impact of early visual experience on facial-expression recognition, we studied children with congenital cataracts who have undergone sight-correcting treatment14,15 and tracked their longitudinal skill acquisition as they gain sight late in life. We introduce and explore two potential facilitators of late-life plasticity: the availability of newborn-like coarse visual acuity prior to treatment16 and the privileged role of motion following treatment.4,17,18 We find that early visual deprivation does not preclude partial acquisition of facial-expression recognition. While rudimentary pretreatment vision is sufficient to allow a low level of expression recognition, it does not facilitate post-treatment improvements. Additionally, only children commencing vision with high visual acuity privilege the use of dynamic cues. We conclude that skipping typical visual experience early in development and introducing high-resolution imagery late in development restricts, but does not preclude, facial-expression skill acquisition and that the representational mechanisms driving this learning differ from those that emerge during typical visual development.

From onset to blindness: a comprehensive analysis of RPGR-associated X-linked retinopathy in a large cohort in China.

BACKGROUND: Variants in the RPGR are the leading cause of X-linked retinopathies (XLRPs). Further in-depth investigation is needed to understand the natural history. METHODS: Review of all case records, molecular genetic testing results, best-corrected visual acuity (BCVA), retinal imaging data (including fundus autofluorescence imaging and optical coherence tomography (OCT)), static visual field (VF) assessments and full-field electroretinogram. RESULTS: Genetic testing was conducted on 104 male patients from 89 family pedigrees, identifying 22 novel variants and 1 de novo variant. The initial symptoms appeared in 78.2% of patients at a median age of 5 years. BCVA declined at a mean rate of 0.02 (IQR, 0-0.04) logarithm of the minimum angle of resolution per year, with a gradual, non-linear decrease over the first 40 years. Autofluorescence imaging revealed macular atrophy at a median age of 36.1 (IQR, 29.9-43.2) years. Patients experienced blindness at a median age of 42.5 (IQR, 32.9-45.2) years according to WHO visual impairment categories. OCT analysis showed a mean ellipsoid zone narrowing rate of 23.3 (IQR, -1.04-22.29) µm/month, with an accelerated reduction in the first 40 years (p<0.01). The median age at which ERG no longer detected a waveform was 26.5 (IQR, 20.5-32.8) years. Comparison by variant location indicated faster progression in patients with exon 1-14 variants during the initial two decades, while those with ORF15 variants showed accelerated progression from the third decade. CONCLUSIONS: We provide a foundation for determining the treatment window and an objective basis for evaluating the therapeutic efficacy of gene therapy for XLRP.

[The effect of various visual impairments on the daily activities of older patients.]

Visual impairment due to ophthalmological diseases significantly affects functional activity in everyday life, since good eyesight is crucial in daily activities. Data from 837 respondents were studied, allowing for analysis of such medical and demographic indicators as age, gender, level of education, visual acuity arterial hypertension and diabetes mellitus. To measure functional status, the main activities in daily life (ADL) and instrumental activities in daily life (IADL) were evaluated using a modified version of the Katz scale and the IADL OARS scale. Statistical methods of Mantel-Hansel Chi-squared analysis were used to assess differences in the prevalence of functional blindness and visual deficit. The study showed that medical and demographic factors have a relatively smaller impact on vision deficiency compared to functional blindness, with age being a significant factor in both cases. Among the medical and demographic factors, the age of patients, as well as diabetes mellitus, significantly increase the development of visual deficiency and functional blindness. Functional blindness, in comparison with visual deficiency, causes more significant restrictions on activities in everyday life and instrumental activities in everyday life, and also causes dependence on help from others.

Blind individuals' enhanced ability to sense their own heartbeat is related to the thickness of their occipital cortex.

Blindness is associated with heightened sensory abilities, such as improved hearing and tactile acuity. Moreover, recent evidence suggests that blind individuals are better than sighted individuals at perceiving their own heartbeat, suggesting enhanced interoceptive accuracy. Structural changes in the occipital cortex have been hypothesized as the basis of these behavioral enhancements. Indeed, several studies have shown that congenitally blind individuals have increased cortical thickness within occipital areas compared to sighted individuals, but how these structural differences relate to behavioral enhancements is unclear. This study investigated the relationship between cardiac interoceptive accuracy and cortical thickness in 23 congenitally blind individuals and 23 matched sighted controls. Our results show a significant positive correlation between performance in a heartbeat counting task and cortical thickness only in the blind group, indicating a connection between structural changes in occipital areas and blind individuals' enhanced ability to perceive heartbeats.

Visual outcome of penetrating ocular trauma among patients visiting University of Gondar comprehensive specialized hospital.

Ocular trauma, a preventable public health issue, is one of the common causes of ophthalmic morbidity and monocular blindness worldwide. It can occur in almost any setting and at any age in either sex but largely affects males. The mechanism and type of injury, the extent of damage, and the time-lapse between the occurrence of injury and eye care are among the factors that determine the visual outcome of ocular injuries. This study is designed to assess the clinical profile and visual outcome of patients presenting with penetrating ocular injury. A prospective hospital-based study was conducted among penetrating ocular trauma patients who visited UOG tertiary eye care and training center during the study period. All patients with penetrating ocular trauma who fulfilled the inclusion criteria were included in the study. Data on demography, initial and final visual acuity, type of injury, as well as management, were included in a structured questionnaire. The collected data were processed and analysed using Statistical Packages for the Social Sciences (SPSS) version 25.0. The study included 91 cases of penetrating ocular injuries. The majority of the patients 81.2% were males. The male-to-female ratio was 4.3:1. The left eye was involved in 52.7% of the patients. The median age was 20 years, with an IQR of 10-35. The majority (31.9%) of the cases were in the age range of 5-10 years. nearly half of the study participants (45.1%) sustained the injury at home. The commonest source of injury was wooden sticks 49.5%. Six patients were lost to follow-up at three-month visits. Traumatic cataracts (p = 0.001), and poor initial visual acuity were poor prognostic factors. Still ocular injury is a common cause of monocular blindness. We recommend that more has to be done on the primary prevention and control measures.

Pattern-reversal visual evoked potentials in prosthetic vision and simulated visual reduction.

OBJECTIVE: To quantitatively evaluate visual evoked potentials (VEPs) in prosthetic vision and simulated visual reduction. METHODS AND ANALYSIS: Four blind patients implanted with the Argus II retinal prosthesis and seven sighted controls participated. VEPs were recorded with pattern-reversal stimuli (2 cycles of a horizontal square wave grating, 0.1 cycle/degree) at 1.07 reversals per second (rps) for Argus II subjects and 3.37 rps for controls. Argus II patients had both eyes patched, viewing the pattern solely through their implant. Controls viewed the pattern monocularly, either with their best-corrected vision or with simulated visual reduction (field restriction, added blur or reduced display contrast). RESULTS: VEPs recorded in Argus II patients displayed a similar shape to normal VEPs when controls viewed the pattern without simulated visual reduction. In sighted controls, adding blur significantly delayed the P100 peak time by 8.7 ms, 95% CI (0.9, 16.6). Reducing stimulus contrast to 32% and 6% of full display contrast significantly decreased P100 amplitude to 55% (37%, 82%) and 20% (13%, 31%), respectively. Restriction on the field of view had no impact on either the amplitude or the peak latency of P100. CONCLUSION: The early visual cortex in retinal prosthesis users remains responsive to retinal input, showing a similar response profile to that of sighted controls. Pattern-reversal VEP offers valuable insights for objectively evaluating artificial vision therapy systems (AVTSs) when selecting, fitting and training implant users, but the uncertainties in the exact timing and location of electrode stimulation must be considered when interpreting the results.

Changing trend of cataract blindness and visual outcomes after cataract surgery in adults aged 50 years and older: findings from the national eye surveys in Malaysia.

BACKGROUND/AIMS: Population surveys are required to measure the prevalence of cataract blindness in the community. We conducted simultaneous surveys in two regions in Malaysia in 2023 to estimate the prevalence of untreated cataract, measure the visual outcomes after cataract surgery and compare the results with the survey in 2014. METHODS: The surveys were done in Eastern and Sarawak administrative regions using the rapid assessment of avoidable blindness technique. It involved a multistage cluster sampling method, each cluster comprising 50 residents aged 50 years and older. The prevalence of cataract was determined through a visual acuity (VA) check and eye examination. The VA of those who had undergone cataract surgery was measured, and the findings were compared with the previous survey. RESULTS: A total of 9709 subjects, 50 years old and older, were examined (percentages of response were 94.5% and 96.2% for Eastern and Sarawak, respectively). Comparing the current to the previous survey in 2014, the prevalence of cataract at all levels of surgical thresholds (except unilateral VA <6/60 and <6/18 in the Eastern) was reduced. The percentages of cataract surgery visual outcomes with good VA (6/12) were improved, and those with poor VA (<6/60) were reduced in both regions. CONCLUSION: There was a reduction in cataract prevalence and improved visual outcomes in both regions. These favourable results could be attributed to the surgical performance monitoring initiatives and the community cataract programme implemented soon after the survey in 2014.

Assessing the cataract surgical rate and gender equity in cataract services in south-east Nigeria.

BACKGROUND: In 2020, almost 100 million people were blind or visually impaired from cataract. Cataract surgery is a cost-effective treatment for cataracts. In Nigeria, twice as many women are cataract blind as men. Cataract surgical rate (CSR, the number of cataract operations per million population per year in a defined geographical location) is an output indicator of cataract surgical services. The recommended target CSR for sub-Saharan Africa is 1000/year. The aim of this study was to assess the CSR in men and women in Imo state, Nigeria. METHODS: A retrospective review of cataract surgery undertaken in all eye health facilities in Imo State in 2019. Data collected included the type and location of facilities, patient demographics and the number and type of cataract operations performed in each facility. The CSR was calculated overall, in men and women, and in younger and older women. RESULTS: The CSR overall was 330/million and was slightly higher in women (347/million) than in men (315/million) (p<0.001). More elderly women (≥65 years) accessed cataract surgery through outreach than men and younger women (OR 1.5 (95% CI 1.03 to 2.22, p=0.03) and 1.6 (95% CI 1.07 to 2.44, p=0.02)), respectively. CONCLUSION: The overall CSR in Imo state was approximately one-third of that recommended for sub-Saharan Africa. Although the CSR was higher in women than in men, considerably higher CSRs are needed in women to address their higher burden of cataract blindness. Operational and intervention science research are needed, to identify and evaluate interventions which address demand and supply barriers to accessing cataract surgery, particularly for elderly women.

Screening Strategies and Methodologies.

PRCIS: While glaucoma is a leading cause of irreversible vision loss, it presents technical challenges in the design and implementation of screening. New technologies such as PRS and AI offer potential improvements in our ability to identify people at high risk of sight loss from glaucoma and may improve the viability of screening for this important disease. PURPOSE: To review the current evidence and concepts around screening for glaucoma. METHODS/RESULTS: A group of glaucoma-focused clinician scientists drew on knowledge and experience around glaucoma, its etiology, and the options for screening. Glaucoma is a chronic progressive optic neuropathy affecting around 76 million individuals worldwide and is the leading cause of irreversible blindness globally. Early stages of the disease are asymptomatic meaning a substantial proportion of cases remain undiagnosed. Early detection and timely intervention reduce the risk of glaucoma-related visual morbidity. However, imperfect tests and a relatively low prevalence currently limit the viability of population-based screening approaches. The diagnostic yield of opportunistic screening strategies, relying on the identification of disease during unrelated health care encounters, such as cataract clinics and diabetic retinopathy screening programs, focusing on older people and/or those with a family history, are hindered by a large number of false-positive and false-negative results. Polygenic risk scores (PRS) offer personalized risk assessment for adult-onset glaucoma. In addition, artificial intelligence (AI) algorithms have shown impressive performance, comparable to expert humans, in discriminating between potentially glaucomatous and non-glaucomatous eyes. These emerging technologies may offer a meaningful improvement in diagnostic yield in glaucoma screening. CONCLUSIONS: While glaucoma is a leading cause of irreversible vision loss, it presents technical challenges in the design and implementation of screening. New technologies such as PRS and AI offer potential improvements in our ability to identify people at high risk of sight loss from glaucoma and may improve the viability of screening for this important disease.