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result(s) for
"de Oliveira, Paulo Ricardo Chaves"
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B-scan ultrasound, visual electrophysiology and perioperative videoendoscopy for predicting functional results in keratoprosthesis candidates
by
Salomão, Solange Rios
,
Berezovsky, Adriana
,
Silva, Luzia Diegues
in
Artificial Organs
,
Clinical science
,
Cornea
2022
Background/AimsWe analysed the ability of B-scan ultrasound, ocular electrophysiology testing and videoendoscopic examination for predicting visual prognosis in Boston Type 1 keratoprosthesis (KPro-1) candidates. Indirect anatomical and electrophysiological findings and results from direct endoscopic evaluations were correlated with postoperative functional data.MethodsIn this prospective and interventional study, we included 13 individuals who had previously been indicated for Kpro-1 surgery. All subjects underwent preoperative screening, including ophthalmic evaluation, B-scan ultrasound, electrophysiological testing, and perioperative intraocular videoendoscopic evaluation (VE). B-scan ultrasound, electrophysiological testing, and VE evaluation results were categorised as favourable or unfavourable predictors of postoperative functional results according to predefined criteria. The predictability values of B-scan ultrasound, electrophysiological testing, and VE prognostication were calculated based on the visual acuity level achieved.ResultsAll surgeries and perioperative VEs were uneventful. Preoperative best-corrected visual acuity (BCVA) ranged from light perception to counting fingers. The 1-year postoperative BCVA was better than 20/200 (satisfactory visual acuity result) in 10 eyes (76.9%) and 20/40 or better in 5 eyes (38.5%). B-scan ultrasound presented a positive predictive value (PPV) of 85.7% for satisfactory postoperative visual acuity, electroretinography showed a PPV of 66.7%, and visual evoked potential presented a PPV of 66.7%. The perioperative VE PPV of a negative finding for satisfactory visual acuity was 100%.ConclusionsFundoscopic visualisation by intraocular VE is a minimally invasive procedure that can be used to predict functional outcomes in keratoprosthesis candidates. This technique demonstrated better prognostication in keratoprosthesis candidates than B-scan ultrasound and electrophysiological testing.
Journal Article
Vitreoretinal instruments: vitrectomy cutters, endoillumination and wide-angle viewing systems
by
Berger, Alan Richard
,
de Oliveira, Paulo Ricardo Chaves
,
Chow, David Robert
in
Medicine
,
Medicine & Public Health
,
Ophthalmology
2016
There have been many advances in vitreoretinal surgery since Machemer introduced the concept of pars plana vitrectomy, in 1971. Of particular interest are the changes in the vitrectomy cutters, their fluidics interaction, the wide-angle viewing systems and the evolution of endoillumination through the past decade and notably in the last few years. The indications of 27-gauge surgery have expanded, including more complex cases. Cut rates of up to 16,000 cuts per minute are already available. New probe designs and pump technology have allowed duty cycle performances of near 100% and improved flow control. The smaller vitrectomy diameter can be positioned between narrow spaces, allowing membrane dissection and serving as a multifunctional instrument. Enhanced endoillumination safety can be achieved by changing the light source, adding light filters, increasing the working distance and understanding the potential interactions between light and vital dyes commonly used to stain the retina. Wide-angle viewing systems (contact, non-contact or a combination of both) provide a panoramic view of the retina. Non-contact systems are assistant-independent, while contact systems may be associated with better image resolution. This review will cover some current aspects on vitrectomy procedures, mainly assessing vitrectomy cutters, as well as the importance of endoillumination and the use of wide-angle viewing systems.
Journal Article
Use of Evicel Fibrin Sealant in Optic Disc Pit-Associated Macular Detachment
by
Berger, Alan Richard
,
de Oliveira, Paulo Ricardo Chaves
,
Chow, David Robert
in
Adult
,
Congenital diseases
,
Eye Abnormalities - complications
2017
Optic disc pit is a rare congenital anomaly of the optic nerve. Retinal detachment is a common complication with poor outcomes. Many surgical alternatives have been described for the treatment of this condition, producing variable results. Herein, the authors describe four cases of optic disc pit-associated macular detachment managed with pars plana vitrectomy, fluid-air exchange, drainage of subretinal fluid through the optic disc pit, temporal peripapillary laser, and application of Evicel fibrin sealant (human) (Ethicon, Bridgewater, NJ) over the optic disc head. Case 1 showed stable visual acuity and improvement of subretinal fluid. Cases 2 and 3 showed visual acuity and subretinal fluid improvements. At the 1-week follow-up visit, Case 4 showed almost total subretinal fluid absorption. The sealant invariably disappeared between 1 and 2 weeks and was tolerated by all patients. This case series suggests that Evicel fibrin sealant may be considered as an adjunctive option in the surgical treatment of optic disc pit-associated maculopathy. [ Ophthalmic Surg Lasers Imaging Retina. 2017;48:358–363.]
Journal Article
Anti-VEGF in a Marathon Runner’s Retinopathy Case
by
Chow, David Robert
,
Oliveira, Paulo Ricardo Chaves de
,
Soon, Alexander Kahjun
in
Care and treatment
,
Case Report
,
Case studies
2016
Central retinal vein occlusion (CRVO) is one of the most common retinal vascular disorders. Intense exercise associated CRVO have been described in otherwise healthy young patients. We describe a case of a young male ultramarathoner who presented with a CRVO, presumably associated with dehydration, making part of a marathon runner’s retinopathy. Resolution of macular edema and subretinal fluid, with visual acuity improvement, was observed after 3 monthly injections of ranibizumab. Our case suggests that dehydration could be involved in the mechanism of CRVO in healthy young patients and ranibizumab may be an effective treatment option for marathon runner’s retinopathy.
Journal Article
Twenty-Seven-Gauge Vitrectomy
by
de Oliveira, Paulo Ricardo Chaves
,
Chow, David Robert
in
Design
,
Diabetes
,
Diabetic retinopathy
2017
Purpose of Review
This paper aims to provide an overview of the currents aspects involving 27-gauge vitrectomy published on the PubMed directory.
Recent Findings
Almost 15 years have passed since the microincision vitrectomy system was introduced. The idea of removing vitreous through a smaller aperture has become a reality and is widely adopted among surgeons. Although not completely accepted, the use of 27-gauge systems has shown encouraging results. Newer vitrectomy platforms and cutter designs have tried to associate high-performance, smaller instruments with better outcomes. Consequently, the indications for 27-gauge vitrectomy have broadened during the last few years.
Summary
Twenty-seven-gauge vitrectomy seems to be safe and feasible in a variety of vitreoretinal scenarios.
Journal Article
Optical Coherence Tomography Angiography of Chorioretinal Diseases
by
Regatieri, Caio V.
,
Lane, Mark
,
Rosenfeld, Philip
in
Choroid - pathology
,
Choroid Diseases - diagnosis
,
Eye diseases
2016
Fluorescein angiography (FA) and indocyanine green angiography (ICGA) have been the gold standard for the evaluation of retinal and choroidal vasculature in the last three decades and have revolutionized the diagnosis of retinal and choroidal vascular diseases. The advantage of these imaging modalities lies in their ability to document retinal and choroidal vasculature through the dynamic assessment of contrast transit over time in the intravascular and extravascular spaces. However, disadvantages include the absence of depth resolution, blurring of details by contrast leakage, and the inability to selectively evaluate different levels of the retinal and choroidal microvasculature. In addition, these angiographic methods require intravenous dye, which may cause adverse reactions such as nausea, vomiting, and rarely, anaphylaxis. Optical coherence tomography angiography (OCTA) is a noninvasive imaging technique that, in contrast to dye-based angiography, is faster and depth-resolved, allowing in some cases for more precise evaluation of the vascular plexuses of the retina and choroid. The method has been demonstrated in the assessment of various vascular diseases such as venous occlusions, diabetic retinopathy, macular neovascularization, and others. Limitations of this imaging modality include a small registered field of view and the inability to visualize leakage and dye transit over time. It is also subject to a variety of artifacts, including those generated by blinking and eye movement during image acquisition. However, more than an alternative for FA and ICGA, OCTA is bringing new insights to our understanding of retinal and choroidal vascular structure and is changing fundamental paradigms in the clinical management of pathologic conditions. [ Ophthalmic Surg Lasers Imaging Retina . 2016;47:848–861.]
Journal Article
Water strategy improves the inflorescence primordia formation of 'Arra 15' grapevine in the Brazilian semiarid region
by
de Melo Chaves, Agnaldo Rodrigues
,
Teodoro, Paulo Eduardo
,
Silva, Jucicléia Soares da
in
631/449
,
704/172
,
Brazil
2024
Failure in irrigation management of grapevines grown in the Brazilian semiarid region can affect bud fertility. Adequate irrigation, considering both the development of bunches in the current cycle and the formation of fertile buds for subsequent cycles, can bring significant advances to viticulture. Therefore, the objective of this research was to investigate the effect of different irrigation levels during flowering on the formation of buds and potential bunches of 'Arra 15' grapevine and its relationship with metabolic processes. A field experiment was carried out in a commercial vineyard in Petrolina, Pernambuco, Brazil, during the 2021 and 2022 seasons. The experiment was designed in randomized blocks with four replications and five irrigation levels (70; 85; 100; 115 and 130% of crop evapotranspiration – ETc) during three production cycles. The variables fertile bud, vegetative bud, dead bud, potential fertility of the basal, median, and apical regions of the branches, number of potential bunches, reducing sugar, total soluble sugar, net photosynthesis, stomatal conductance, transpiration, and relative chlorophyll index were evaluated. The 115% ETc irrigation level improved the number of fertile buds and number of potential bunches. Irrigation level above 115% ETc increased gas exchange and relative chlorophyll index, while 70% ETc increased leaf sugar content. The most appropriate irrigation strategy is the application of 115% ETc during the flowering stage, for the increase of fertile buds and potential bunches of the next cycle, without influencing the vine metabolism. Total soluble sugars are a promising indicator of water deficit during flowering and as an indicator of vegetative bud formation for the next cycle.
Journal Article
Yellow Fever Virus Maintained by Sabethes Mosquitoes during the Dry Season in Cerrado, a Semiarid Region of Brazil, in 2021
by
Gonçalves-dos-Santos, Maria Eduarda
,
Chaves, Danielle Costa Capistrano
,
Albuquerque, George R.
in
Amazonia
,
Animals
,
Arbovirus
2023
In recent decades, waves of yellow fever virus (YFV) from the Amazon Rainforest have spread and caused outbreaks in other regions of Brazil, including the Cerrado, a savannah-like biome through which YFV usually moves before arriving at the Atlantic Forest. To identify the vectors involved in the maintenance of the virus in semiarid environments, an entomological survey was conducted after confirmation of yellow fever (YF) epizootics at the peak of the dry season in the Cerrado areas of the state of Minas Gerais. In total, 917 mosquitoes from 13 taxa were collected and tested for the presence of YFV. Interestingly, mosquitoes of the Sabethes genus represented 95% of the diurnal captured specimens, displaying a peak of biting activity never previously recorded, between 4:30 and 5:30 p.m. Molecular analysis identified three YFV-positive pools, two from Sabethes chloropterus—from which near-complete genomes were generated—and one from Sa. albiprivus, whose low viral load prevented sequencing. Sa. chloropterus was considered the primary vector due to the high number of copies of YFV RNA and the high relative abundance detected. Its bionomic characteristics allow its survival in dry places and dry time periods. For the first time in Brazil, Sa. albiprivus was found to be naturally infected with YFV and may have played a role as a secondary vector. Despite its high relative abundance, fewer copies of viral RNA were found, as well as a lower Minimum Infection Rate (MIR). Genomic and phylogeographic analysis showed that the virus clustered in the sub-lineage YFVPA-MG, which circulated in Pará in 2017 and then spread into other regions of the country. The results reported here contribute to the understanding of the epidemiology and mechanisms of YFV dispersion and maintenance, especially in adverse weather conditions. The intense viral circulation, even outside the seasonal period, increases the importance of surveillance and YFV vaccination to protect human populations in affected areas.
Journal Article
Stratification of complexity in congenital heart surgery: comparative study of the Risk Adjustment for Congenital Heart Surgery (RACHS-1) method, Aristotle basic score and Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STS-EACTS) mortality score
by
Esmeraldo, Isaac Melo
,
Lins, Ricardo Felipe de Albuquerque
,
Lima, Ricardo de Carvalho
in
CARDIAC & CARDIOVASCULAR SYSTEMS
,
Cardiology
,
Cardiopatias Congênitas
2015
Objective: To determine whether stratification of complexity models in congenital heart surgery (RACHS-1, Aristotle basic score and STS-EACTS mortality score) fit to our center and determine the best method of discriminating hospital mortality. Methods: Surgical procedures in congenital heart diseases in patients under 18 years of age were allocated to the categories proposed by the stratification of complexity methods currently available. The outcome hospital mortality was calculated for each category from the three models. Statistical analysis was performed to verify whether the categories presented different mortalities. The discriminatory ability of the models was determined by calculating the area under the ROC curve and a comparison between the curves of the three models was performed. Results: 360 patients were allocated according to the three methods. There was a statistically significant difference between the mortality categories: RACHS-1 (1) - 1.3%, (2) - 11.4%, (3)-27.3%, (4) - 50 %, (P<0.001); Aristotle basic score (1) - 1.1%, (2) - 12.2%, (3) - 34%, (4) - 64.7%, (P<0.001); and STS-EACTS mortality score (1) - 5.5 %, (2) - 13.6%, (3) - 18.7%, (4) - 35.8%, (P<0.001). The three models had similar accuracy by calculating the area under the ROC curve: RACHS-1- 0.738; STS-EACTS-0.739; Aristotle- 0.766. Conclusion: The three models of stratification of complexity currently available in the literature are useful with different mortalities between the proposed categories with similar discriminatory capacity for hospital mortality.
Journal Article