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1.
JGH Open ; 8(5): e13058, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38737501

RESUMEN

Background and Aim: Small rectosigmoid colorectal polyps (<10 mm) are prevalent, with a low prevalence of advanced neoplastic lesions. The "diagnose-and-leave" strategy, employing narrow band imaging (NBI), is gaining popularity for its safety and cost-effectiveness by reducing polypectomy complications and minimizing histopathology expenses. This study assessed the diagnostic efficacy of NBI with dual focus (DF) magnification for real-time neoplastic prediction of rectosigmoid polyps and explored the feasibility of implementing this strategy in Vietnam. Methods: In a prospective single-center study, 307 rectosigmoid polyps from 245 patients were analyzed using three consecutive endoscopic modes: white light endoscopy (WLE), NBI, and NBI-DF. Endoscopists assessed polyps for size, location, macroscopic shape, optical diagnosis, and confidence levels before histopathological evaluation. High confidence was assigned when the polyp exhibited all features of a single histology type. Predictions were compared with final histopathology results. Results: Of the total, 237 (77.2%) were diminutive (≤5 mm) polyps, and 18 (5.8%) were advanced neoplastic lesions. WLE + NBI and WLE + NBI + NBI-DF exhibited significantly higher accuracy compared to WLE (88.6% and 90.2% vs 74.2%, P < 0.01). For diminutive polyps, the DF mode significantly increased the rate of high-confidence optical diagnoses (89.1% vs 94.9%, P < 0.001). WLE + NBI + NBI-DF demonstrated high sensitivity (90.1%), specificity (95.5%), and negative predictive value (93.4%) in high-confidence predictions, enabling the implementation of the "diagnose-and-leave" strategy. This approach would have reduced 58.2% of unnecessary polypectomies without missing any advanced neoplastic lesions. Conclusion: NBI and DF modes provide accurate neoplastic predictions for rectosigmoid polyps. For diminutive polyps, DF magnification improves the confidence level of the optical diagnosis, allowing the safe implementation of the "diagnose-and-leave" strategy.

2.
Cureus ; 16(2): e53545, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38445134

RESUMEN

Background and objectives Achieving accurate real-time optical diagnoses of colorectal polyps with high-confidence predictions is crucial for appropriate decision-making in daily practice. The dual-focus (DF) magnification mode helps endoscopists scrutinize subtle features of polyp surfaces and vessel patterns. This prospective study aimed to evaluate the impact of DF imaging on enhancing the rate of high-confidence narrow-band imaging (NBI)-based optical diagnosis. Methods Consecutive adult patients who underwent colonoscopy and had small colorectal polyps (<10 mm) were enrolled between September 2022 and May 2023. The optical diagnosis of each polyp was evaluated during colonoscopy in two stages by the same endoscopist, utilizing NBI with DF magnification (NDB-DF). A confidence level was assigned to each prediction. High confidence was indicated by clinical judgment when a polyp exhibited distinctive features associated solely with one histological subtype and lacked characteristics of any other subtype. All procedures were carried out with a prototype 190 series Exera III NBI system (Olympus Corporation, Tokyo, Japan) with DF magnification. Results The study included 413 patients with 623 polyps, comprising 483 ≤ 5 mm and 140 measuring 6-9 mm. The majority were low-grade adenomas (343 lesions), with 17 identified as high-grade adenomas, and none characterized as deep submucosal invasive carcinomas. NBI-DF significantly improved the rate of high-confidence optical diagnoses compared to NBI for both ≤ 5 mm polyps (93.1% vs. 87.5%, p < 0.0001) and 6-9 mm polyps (97.9% vs. 94.2%, p = 0.03). Furthermore, DF significantly facilitated the assessment of microvessel and surface pattern criteria (p < 0.01). Conclusion DF magnification markedly enhanced the rate of high-confidence NBI-based optical predictions for small colorectal polyps. This technique demonstrates the potential for improving the diagnostic yield in real-time optical diagnosis of colorectal polyps in the Vietnamese setting.

3.
Life (Basel) ; 14(1)2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38255733

RESUMEN

We aim to investigate the myopic control effect of high-concentration atropine (ATR) and dual-focus contact lenses (DFCLs). A retrospective cohort study was conducted. A total of 182 eyes in 91 individuals who used high-concentration ATR (0.125%) and another 70 eyes in 35 individuals who used DFCLs were enrolled in the ATR and DFCL groups, respectively. The primary outcomes were spherical equivalent refraction (SER) progression and axial length (AXL) elongation. The generalized estimate equation was utilized to yield the adjusted odds ratio (aOR) and 95% confidence interval (CI) of cycloplegic SER progression and AXL elongation between groups. According to the multivariable analysis, the change in cycloplegic SER progression was similar between the DFCL and ATR groups (aOR: 1.305, 95% CI: 0.247-2.515, p = 0.803). The DFCL group demonstrated a numerically higher rate of AXL elongation compared to the ATR group (aOR: 1.530, 95% CI: 0.980-1.894, p = 0.051). In the subgroup analysis, cycloplegic SER progression was insignificant between ATR and DFCL users in different subgroups (all p > 0.05). The DFCL patients with moderate astigmatism and high AXL (both p < 0.001) presented a high risk of AXL elongation. In conclusion, DFCL usage demonstrated similar myopic control of cycloplegic SER and AXL compared to high-concentration ATR, while DFCLs showed lower AXL control, mainly in patients with moderate astigmatism and high AXL.

4.
Ophthalmic Physiol Opt ; 44(2): 270-279, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38193312

RESUMEN

PURPOSE: To review the rebound effect after cessation of different myopia control treatments. METHODS: A systematic review that included full-length randomised controlled studies (RCTs), as well as post-hoc analyses of RCTs reporting new findings on myopia control treatments rebound effect in two databases, PubMed and Web of Science, was performed according to the PRISMA statement. The search period was between 15 June 2023 and 30 June 2023. The Cochrane risk of bias tool was used to analyse the quality of the selected studies. RESULTS: A total of 11 studies were included in this systematic review. Unifying the rebound effects of all myopia control treatments, the mean rebound effect for axial length (AL) and spherical equivalent refraction (SER) were 0.10 ± 0.07 mm [-0.02 to 0.22] and -0.27 ± 0.2 D [-0.71 to -0.03] after 10.2 ± 7.4 months of washout, respectively. In addition, spectacles with highly aspherical lenslets or defocus incorporated multiple segments technology, soft multifocal contact lenses and orthokeratology showed lower rebound effects compared with atropine and low-level light therapy, with a mean rebound effect for AL and SER of 0.04 ± 0.04 mm [0 to 0.08] and -0.13 ± 0.07 D [-0.05 to -0.2], respectively. CONCLUSIONS: It appears that the different treatments for myopia control produce a rebound effect after their cessation. Specifically, optical treatments seem to produce less rebound effect than pharmacological or light therapies. However, more studies are required to confirm these results.


Asunto(s)
Anteojos , Miopía , Procedimientos de Ortoqueratología , Refracción Ocular , Humanos , Miopía/terapia , Miopía/fisiopatología , Refracción Ocular/fisiología , Procedimientos de Ortoqueratología/métodos , Terapia por Luz de Baja Intensidad/métodos
5.
Cont Lens Anterior Eye ; 47(1): 102095, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38057197

RESUMEN

BACKGROUND: Soft contact lenses have been developed and licensed for reducing myopia progression. These lenses have different designs, such as extended depth of focus (EDOF) and dual focus (DF). In this prospective, double-masked, cross-over study, different lens designs were investigated to see whether these had impact on accommodative microfluctuations and eye movements during reading. METHODS: Participants were fitted with three lenses in a randomised order; a single vision (SV) design (Omafilcon A2; Proclear), a DF design (Omafilcon A2; MiSight), and an EDOF lens design (Etafilcon A; NaturalVue),. Accommodative microfluctuations were measured at 25 cm for at least 60s in each lens, using a Shin-Nippon SRW-5000 autorefractor adapted to continuously record accommodation at 22Hz. Eye movement data was collected with the Thomson Clinical Eye Tracker incorporating a Tobii Eye bar. Eye movements include fixations per row, fixations per minute, mean regressions per row, total number of regressions, and total rightward saccades. Accommodation data was analysed using power spectrum analysis. Differences between the lenses were compared using a related sample two-way Friedman test. RESULTS: Twenty-three participants (18-29 years) were recruited to take part. The average mean spherical error was -2.65D ± 1.42DS, with an average age of 23.4 ± 3.5 years. No significant difference for accommodative microfluctuations was found. Significant differences were found for fixations per row (P = 0.03), fixations per minute (P = 0.008), mean regressions per row (P = 0.002), and total number of regressions (P = 0.002), but not total rightward saccades (P = 0.10). Post-hoc analysis indicated the EDOF lens results were significantly different from the other lenses, with more regressive eye movements observed. CONCLUSIONS: Regressive saccades appear to increase when wearing EDOF lens designs, which may impact visual comfort. Further studies in children, over a longer period of adaptation are necessary to assess the potential impact of this finding on daily reading activities in children.


Asunto(s)
Lentes de Contacto Hidrofílicos , Miopía , Niño , Humanos , Adulto Joven , Adulto , Movimientos Oculares , Lectura , Estudios Cruzados , Estudios Prospectivos , Acomodación Ocular , Miopía/terapia
6.
Int Ophthalmol ; 43(11): 4247-4261, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37596425

RESUMEN

PURPOSE: To investigate the knowledge, training and clinical practice of Spanish optometrists about preventing and controlling myopia progression. METHODS: A web-based questionnaire was distributed to Spanish optometrists through social networks, optometric professional bodies and one of the major Spanish optometrists' associations to assess practitioner perception, understanding, and self-reported clinical practice behavior related to myopia diagnosis and management. RESULTS: A total of 534 optometrists with a mean age of 40.8 ± 10.3 years completed the survey. Most respondents have been practicing optometry for more than 20 years (89.8%), report having actively treated childhood myopia (82.4%), and are very concerned about the increasing frequency of pediatric myopia in their daily practice (85.3%). Almost all of the respondents (97.3%) agreed that the efficacy of treatment is related to the age at which it is prescribed, and more than half (53.6%) considered a progression higher than - 0.50 and up to - 1.00D as the minimum necessary to consider a myopia management option. Respondents who reported actively managing childhood myopia considered orthokeratology, atropine and soft-defocus contact lenses the most effective myopia control interventions. However, the most frequently prescribed form of myopia correction by Spanish optometrists was single-vision spectacles, followed by orthokeratology and soft-defocus contact lenses. CONCLUSIONS: Spanish optometrists are very active in the management of myopia, especially by fitting orthokeratology lenses or dual-focus soft contact lenses for myopia control, but there is still potential for improvement in the methodology they follow for both the diagnosis and management of myopia.


Asunto(s)
Lentes de Contacto Hidrofílicos , Miopía , Optometristas , Humanos , Niño , Adulto , Persona de Mediana Edad , Miopía/diagnóstico , Miopía/prevención & control , Atropina , Actitud
7.
Clin Endosc ; 56(4): 479-489, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37501625

RESUMEN

BACKGROUND/AIMS: Accurate neoplastic prediction can significantly decrease costs associated with pathology and unnecessary colorectal polypectomies. Narrow band imaging (NBI) and dual-focus (DF) mode are promising emerging optical technologies for recognizing neoplastic features of colorectal polyps digitally. This study aimed to clarify the clinical usefulness of NBI with and without DF assistance in the neoplastic prediction of small colorectal polyps (<10 mm). METHODS: This cross-sectional study included 530 small colorectal polyps from 343 consecutive patients who underwent colonoscopy at the University Medical Center from September 2020 to May 2021. Each polyp was endoscopically diagnosed in three successive steps using white-light endoscopy (WLE), NBI, and NBI-DF and retrieved for histopathological assessment. The diagnostic accuracy of each modality was evaluated with reference to histopathology. RESULTS: There were 295 neoplastic polyps and 235 non-neoplastic polyps. The overall accuracies of WLE, WLE+NBI, and WLE+NBI+NBI-DF in the neoplastic prediction of colorectal polyps were 70.8%, 87.4%, and 90.8%, respectively (p<0.001). The accuracy of WLE+NBI+NBI-DF was significantly higher than that of WLE+NBI in the polyp size ≤5 mm subgroup (87.3% vs. 90.1%, p<0.001). CONCLUSION: NBI improved the real-time neoplastic prediction of small colorectal polyps. The DF mode was especially useful in polyps ≤5 mm in size.

8.
Nano Lett ; 23(8): 3152-3158, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37015348

RESUMEN

Metalenses with two foci in the longitudinal or transverse direction, called bifocal or dual-focus metalenses, are promising building blocks in tomography techniques, data storage, and optical tweezers. For practical applications, relative movement between the beam and specimen is required, and beam scanning is highly desirable for high-speed operation without vibration. However, dual-focus metalenses employ a hyperbolic phase that experiences off-axis aberrations, which is not suitable for beam scanning. Here, we demonstrated a scannable dual-focus metalens by employing a new phase called "hybrid phase". The hybrid phase consists of a hyperbolic phase inside and a quadratic phase outside to reduce off-axis aberrations while maintaining a high numerical aperture. We show that the two foci of the scannable dual-focus metalens move together without severe distortion for incident angles of up to 2.5°. Our design easily extends to the case of multifocusing, which is essential for various applications ranging from imaging to manipulation.

9.
ACS Sens ; 8(1): 71-79, 2023 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-36574494

RESUMEN

The synergistic interaction of vision and olfaction is critical for both natural and artificial intelligence systems to recognize and adapt to complex environments. However, current bioinspired systems with visual and olfactory sensations are mostly assembled with separate and heterogeneous sensors, inevitably leading to bulky systems and incompatible datasets. Here, we demonstrate on-chip integration of visual and olfactory sensations through a dual-focus imaging approach. By combining lens-based visual imaging and lensless colorimetric imaging, a target object and its odor fingerprint can be captured with a single complementary metal-oxide-semiconductor imager, and the obtained multimodal images are analyzed with a bionic learning architecture for information fusion and perception. To demonstrate the capability of this system, we adapted it to food detection and achieved 100% accuracy in identifying meat freshness and category with a 10 s sampling time. In addition to the highly integrated sensor design, our approach exhibits superior accuracy and efficiency in object recognition, providing a promising approach for robotic sensing and perception.


Asunto(s)
Percepción Olfatoria , Olfato , Inteligencia Artificial , Biónica , Percepción Visual
10.
Ophthalmol Sci ; 3(1): 100232, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36545264

RESUMEN

Purpose: To evaluate efficacy and vision with 2 prototype myopia control soft contact lenses with noncoaxial ring-focus designs (for enhancing efficacy [EE] and enhancing vision [EV]) compared with dual-focus (DF) and single-vision (SV) designs. Design: Multicenter, 6-month, randomized, controlled, double-masked clinical trial. Participants: One hundred ninety-nine myopic (-0.75 diopters [D] to -4.50 D) children aged 7 to 12 years. Methods: Participants were randomized with stratification into myopia control (EE, EV, or DF) or SV arms at 9 clinical sites in 3 countries. Postcycloplegia axial length (AL) and spherical equivalent autorefraction (SECAR) were measured at baseline and 26 weeks. Axial length was also measured without cycloplegia at baseline, 1, 4, 13, and 26 weeks. Progression was analyzed using linear mixed models by intention-to-treat population. Visual acuity (VA) and vision quality were monitored. Main Outcome Measures: Axial elongation, change in SECAR. Results: A total of 185 subjects completed the study (n = 44, 49, 45, and 47 for EE, EV, DF, and SV, respectively). There were no serious/significant ocular adverse events. After 26 weeks, EE, EV, and DF all had statistically significantly less axial elongation than SV (unadjusted mean [standard deviation]: EE, 0.079 [0.125]; EV, 0.119 [0.101]; DF, 0.135 [0.117]; SV; 0.189 [0.121] mm). The estimated least-square mean (LSM) differences (adjusted 95% confidence interval) compared with SV were -0.105 (-0.149, -0.062), -0.063 (-0.106, -0.020), and -0.056 (-0.100, -0.013) mm for EE, EV, and DF, respectively. Enhancing efficacy alone had statistically significantly less progression of SECAR than SV (EE: -0.12 [0.27] D vs. SV: -0.35 [0.33] D; LSM difference: 0.22 D [0.09, 0.35]). Enhancing efficacy also had statistically significantly less axial elongation than DF (-0.049 mm [-0.093, -0.004]). Changes in AL and SECAR of EV and DF were not statistically different. All 3 myopia control lenses had mean VA close to 0.00 logarithm of the minimum angle of resolution (logMAR) with estimated 95% upper confidence limits <0.10 logMAR. Enhancing efficacy and DF produced similar reports of halos but more than EV and SV. Conclusions: The prototype contact lenses met the design intent; EE was more efficacious in slowing axial elongation than DF with comparable vision performance, whereas EV produced comparable efficacy to DF with similar vision performance to SV.

11.
J Ophthalmic Vis Res ; 18(4): 359-368, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38250233

RESUMEN

Purpose: To compare the visual performance of two distinct types of soft contact lenses (CL) aimed at slowing down myopia progression with the performance of a monofocal soft CL. Methods: In a prospective double-masked, crossover trial, 18 myopic adults (aged 18-30 years old) were fitted in a randomized order with three types of disposable CL: MiSightTM (dual-focus), MyloTM (extended depth of focus -EDOF-), and ClaritiTM (single distance vision). Measurements were taken after wearing the CL for five days with five days off in between at two different optometry centers. High contrast distance visual acuity (VA) with spectacles and for each of the different CL, subjective refraction, slit lamp exam, aberrometry, stereopsis, monocular and binocular amplitude of accommodation and accommodative facility, and horizontal phorias were measured. Results: The high contrast distance VAwas better for the single vision CL compared to the myopia control CL. No significant differences were observed between the r two myopia control CL. The overall root mean square (RMS) was higher for the double focus CL (RMS = 1.18 ± 0.29 µm), followed by the EDOF CL (RMS = 0.76 ± 0.35 µm) and then the single vision CL (RMS = 0.50 ± 0.19 µm). The primary spherical aberration (SA) mean value was low for all of the three CL, without statistical differences among them. No other significant differences were detected. Conclusion: The overall RMS resulted in a higher value for the dual-focus than the EDOF CL, but no differences in high contrast distance VA and binocularity were detected between them. The monofocal CL's performance was better than the myopia control CL.

12.
Ophthalmic Physiol Opt ; 42(6): 1253-1263, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36006761

RESUMEN

PURPOSE: To determine the efficacy of two myopia control contact lenses (CL) compared with a single-vision (SV) CL. METHODS: Ninety-five Chinese children with myopia, aged 7-13 years in a 1-year prospective, randomised, contralateral, cross-over clinical trial with 3 groups; bilateral SVCL (Group I); randomised, contralateral wear of an extended depth of focus (EDOF) CL and SVCL (Group II) and MiSight® CL and SVCL (Group III). In Groups II and III, CL were crossed over at the 6-month point (Stage 1) and worn for a further 6 months (Stage 2). Group I wore SVCL during both stages. At baseline and the end of each stage, cycloplegic spherical equivalent refractive error (SE) and axial length (AL) were measured. Six-monthly ΔSE/ΔAL across groups was analysed using a linear mixed model (CL type, stage, eye and eye* stage included as factors). Intra-group paired differences between eyes were determined. RESULTS: In Group I, mean (SD) ΔSE/ΔAL with SVCL was -0.41 (0.28) D/0.13 (0.09) mm and -0.25 (0.27) D/0.16 (0.09) mm for stages 1 and 2, with a mean paired difference between eyes of 0.01 D/0.01 mm and 0.05 D/-0.01 mm, respectively. ΔSE/ΔAL with SVCL was similar across Groups I to III (Stage 1: p = 0.89/0.44, Stage 2: p = 0.70/ 0.64). In Groups II and III, ΔSE/ΔAL was lower with the EDOF and MiSight® CL than the contralateral SVCL in 68% to 94% of participants, and adjusted 6-month ΔSE/ΔAL with EDOF was similar to MiSight® (p = 0.49/0.56 for ΔSE/ΔAL, respectively). Discontinuations across the three groups were high, but not different between the groups (33.3%, 48.4% and 50% for Groups I to III, respectively [p = 0.19]) and most discontinuations occurred immediately after baseline. CONCLUSIONS: Extended depth of focus and MiSight® CL demonstrated similar efficacy in slowing myopia. When switched from a myopia control CL to SVCL, myopia progression was similar to that observed with age-matched wearers in SVCL and not suggestive of rebound.


Asunto(s)
Lentes de Contacto Hidrofílicos , Miopía , Niño , Progresión de la Enfermedad , Anteojos , Humanos , Midriáticos , Miopía/prevención & control , Estudios Prospectivos , Refracción Ocular
13.
Ophthalmic Physiol Opt ; 42(6): 1227-1231, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35894156

RESUMEN

PURPOSE: This study compared refractive and axial length (AL) changes in children wearing dual-focus soft contact lenses for myopia control (MiSight®) with myopic children wearing spectacles one year from the start of lockdown during the COVID-19 pandemic. METHODS: This retrospective, descriptive, parallel-group, observational study reviewed the charts of 11 children who began treatment for myopia control with dual-focus soft contact lenses for myopia control (MiSight®) in March 2020 and 11 matched spectacle-wearing controls. The mean increase in spherical equivalent refraction (SER) and AL from the beginning of the lockdown and up to 1 year later were compared. The parents of the children were asked about the average time spent on near work, contact lens wearing time both during and after the strict confinement and whether they had discontinued contact lens wear during lockdown. RESULTS: During this first year of preventive COVID-19 measures (March 2020-March 2021), for the contact lens group the average SER and AL increased -0.14 ± 0.09D and 0.13 ± 0.05 mm, respectively. For the spectacle wearers, the corresponding increases were -0.54 ± 0.16D and 0.25 ± 0.08 mm, respectively. A significant difference was found between the groups for both SER (p < 0.001) and AL (p < 0.05). The average time spent outdoors was restricted for both groups during lockdown and increased after. However, statistically significant changes in the time spent outdoors during and after lockdown were only found for the spectacle group (p < 0.05; t-test), whereas this change was not significant for the contact lens group (p = 0.08). CONCLUSIONS: Over the observed time period, dual-focus soft contact lenses for myopia control were effective despite the decreased time spent outdoors during the COVID-19 pandemic.


Asunto(s)
COVID-19 , Lentes de Contacto Hidrofílicos , Miopía , COVID-19/epidemiología , COVID-19/prevención & control , Niño , Control de Enfermedades Transmisibles , Humanos , Miopía/epidemiología , Miopía/terapia , Pandemias/prevención & control , Refracción Ocular , Estudios Retrospectivos
14.
Se Pu ; 40(4): 354-363, 2022 Apr.
Artículo en Chino | MEDLINE | ID: mdl-35362683

RESUMEN

A method for the determination of 14 polybrominated diphenyl ethers (PBDEs) in human serum using isotope internal standard-gas chromatography-high resolution dual-focus magnetic mass spectrometry (GC-HRMS) was developed. After thawed to room temperature, 0.5 mL serum samples were mixed with 13C-labeled isotopic internal standard. Subsequently, methanol was added to precipitate the proteins in the samples. The effects of three kinds of acids on the removal of cellulite from the serum samples and the corresponding recoveries were compared, and the results revealed that sulfuric acid was the most optimal. The target compounds were extracted by liquid-liquid extraction (LLE), and the effects of different extraction solvents on recoveries were compared. The results indicated that n-hexane (6 mL)-methyl tert-butyl ether (6 mL) was the best extraction solvent. The extracts were cleaned and eluted using solid phase extraction cartridges. Furthermore, the factors that influenced the cleanup effects and recoveries, including the solid phase extraction columns and elution solvents, were investigated in detail. The results indicated that the optimal conditions were cleanup with a silica gel column and elution with hexane-dichloromethane (1∶1, v/v). The eluate was re-dissolved in hexane after being blown to near dryness using nitrogen. The detection of PBDEs was performed using GC-HRMS. The instrument conditions were optimized, and the capillary column used was an Rtx-1614 column (30 m×0.25 mm×0.1 µm). Helium was used as the carrier gas at a flow rate of 1.0 mL/min. The injector temperature was 290 ℃, and the oven temperature was programmed as follows: 150 ℃ for 2 min, 150 ℃ to 250 ℃ at 15 ℃/min, held for 1 min, 250 ℃ to 290 ℃ at 25 ℃/min, held for 3 min, and 290 ℃ to 320 ℃ at 25 ℃/min, held for 12.5 min. The injection volume was 1 µL in splitless mode. The samples were ionized in the positive electron ionization (EI) mode at 35 eV. Precursor ions and the production of each compound were identified using a voltage-selective ion detection (VSIR) program with a resolution of 10000. The ionization temperature was set at 280 ℃, and the transmission line temperature was set at 320 ℃. To ensure the integrity of the separation of low-brominated components, the column separation time was shortened, the response of high-boiling components was improved (BDE-190 and BDE-209), the decomposition of BDE-209 on the chromatographic column was effectively prevented, and the requirement of the simultaneous determination of multiple PBDEs was met. The method demonstrated good linearity in the range of 0.40 to 25 µg/L for BDE-209, and 0.08 to 5 µg/L for the other 13 PBDEs, with correlation coefficients greater than 0.995. The method detection limits (MDLs) were in the range of 0.01 to 0.51 µg/L, and the limits of quantification (LOQs) ranged from 0.04 to 1.70 µg/L. The recoveries of the 14 compounds ranged from 75.5% to 120.7%. The intra-day relative standard deviations (RSDs) were within 3.8%-10.9% (n=6) and the inter-day RSDs were within 4.2% to 12.4% (n=6). This method was successfully applied to the determination of 14 PBDEs in 15 serum samples from an adolescent population in an area. Notably, 1.86 to 4.66 ng/g lipid BDE-47 was detected in the serum samples with a detection frequency of 100%, and the other compounds were not detected. The results imply that the adolescent population in this region was exposed to some PBDE. Compared with the existing methods reported, this method has less sample demand and higher sensitivity and accuracy, can simultaneously determine 14 PBDEs, including BDE-209 in human serum, and effectively improve the efficiency of detection. This study offers a new method for studying the impact of polybrominated diphenyl ethers on population health in China.


Asunto(s)
Éteres Difenilos Halogenados , Extracción en Fase Sólida , Adolescente , Cromatografía de Gases y Espectrometría de Masas/métodos , Éteres Difenilos Halogenados/análisis , Humanos , Isótopos , Fenómenos Magnéticos , Extracción en Fase Sólida/métodos
15.
Ophthalmic Physiol Opt ; 42(4): 753-761, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35305040

RESUMEN

INTRODUCTION: Dual-focus soft contact lenses for myopia management have demonstrated to be an effective strategy to reduce myopia progression. However, this optical design has been shown to alter visual quality and accommodative function. The aim of this study was to examine the accommodative and behavioural performance during the execution of a psychomotor vigilance task (PVT) while wearing dual-focus and single-vision soft contact lenses. METHODS: The steady-state accommodative response was recorded with the WAM-5500 binocular open-field autorefractor during the execution of a 10-min PVT at 50 cm either with the dual-focus (MiSight 1-day) or single-vision (Proclear 1-day) soft contact lenses, using a sample of 23 healthy young adults. Each experimental session was performed on two different days in a counterbalanced order. RESULTS: A greater lag of accommodation, variability of accommodation and reaction time was found while wearing dual-focus in comparison with single-vision soft contact lenses (mean differences during the 10-min PVT were 0.58 ± 0.81 D, p < 0.001; 0.31 ± 0.17 D, p < 0.001 and 15.22 ± 20.93 ms, p = 0.002, respectively). Also, a time-on-task effect was found for the variability of accommodation and reaction time (p = 0.001 and p < 0.001, respectively), observing higher values over time. However, the lag of accommodation did not change significantly as a function of time-on-task (p = 0.33). CONCLUSION: Dual-focus soft contact lens wear influences the steady-state accommodative response and behavioural performance during the execution of a visual vigilance task in the short-term. Eye care practitioners should be aware of these effects when prescribing these lenses for myopia management, and provide specific recommendations according to the individual visual needs.


Asunto(s)
Lentes de Contacto Hidrofílicos , Miopía , Acomodación Ocular , Anteojos , Humanos , Miopía/terapia , Refracción Ocular , Adulto Joven
16.
Cont Lens Anterior Eye ; 45(2): 101426, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-33618977

RESUMEN

BACKGROUND: A range of myopia management (MM) contact lenses are becoming available to practitioners. These lenses are designed to slow myopia progression and axial elongation. This study explored the initial experience of participants wearing daily disposable MM contact lenses to investigate established factors previously associated with successful lens wear. METHODS: This was a prospective, double-masked, crossover study. Twenty participants aged 18-30 years old were assigned to wear two daily disposable MM lenses in a randomised order. Visual acuity, contrast sensitivity, and amplitude/lag of accommodation were assessed at baseline, post-insertion, and after 2 and 6 h of lens wear. Self-reported lens comfort and vision quality were recorded at the same timepoints, and at 10 h post-insertion. Pairwise comparisons were performed between the two lenses at each timepoint, as well as assessing changes throughout wear. The relationship of the measured parameters to overall lens satisfaction was also assessed. RESULTS: There were no significant differences between the two MM lenses at any timepoint for any of the participant-reported parameters, including overall satisfaction. A small difference in visual acuity was noted at 6 h post-insertion, although this is unlikely to be clinically significant. Comfort decreased throughout the day, most notably at 10 h post-insertion. A moderate positive correlation was observed between participant-reported visual quality and overall satisfaction. A similar pattern was seen for comfort and overall satisfaction. Self-reported vision quality and measured visual acuity were poorly correlated, highlighting the benefit of subjectively assessing the quality of vision with these lenses. CONCLUSIONS: The participants demonstrated comparable measures across a range of measures between the two MM lenses. Notably, half of the participants demonstrated a clear lens preference, although the preferred lens varied between individuals. Candidates for MM may benefit from trialling more than one MM lens design, to maximise initial wearing satisfaction.


Asunto(s)
Lentes de Contacto Hidrofílicos , Miopía , Adolescente , Adulto , Estudios Cruzados , Equipos Desechables , Humanos , Miopía/diagnóstico , Miopía/terapia , Evaluación del Resultado de la Atención al Paciente , Satisfacción del Paciente , Estudios Prospectivos , Adulto Joven
17.
Ophthalmic Physiol Opt ; 42(1): 8-18, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34687238

RESUMEN

PURPOSE: To evaluate the refractive impact of dual-focus (DF) myopia control contact lenses (CLs) on accommodating young myopic adults. METHODS: Phase 1: accommodative accuracy was assessed in 40 myopic participants. Phase 2: a subset of four subjects who demonstrated accurate accommodation and six who chronically underaccommodated were fitted with single vision (SV, Proclear 1 day) and centre-distance DF myopia control CLs (MiSight 1 day) with approximately +2.00 D of additional power in two surrounding annular zones. While binocularly viewing high contrast characters at 4.00, 1.00, 0.50, 0.33, 0.25 and 0.20 m, aberrometry data were captured across the central ±30° of the horizontal retina. Local refractive errors were pooled for each area of the pupil covered by the central distance or first annular defocus zone of the DF CLs. RESULTS: In the "good" accommodator group fitted with SV CLs, accommodative lags were generally absent except at the closest viewing distance (mean errors: -0.09 ± 0.22 D, -0.12 ± 0.26 D, -0.05 ± 0.37 D and +0.38 ± 0.54 D for -2.00, -3.00, -4.00 and -5.00 D target vergences, respectively) but significantly larger in the "poor" accommodating participants (+0.81 ± 0.21 D, +0.97 ± 0.27 D, +1.18 ± 0.39 D, +1.47 ± 0.55 D). For most viewing distances, hyperopic defocus observed in the region of the pupil covered by the first annular zone was replaced with myopic defocus when fitted with the DF CLs. Myopic defocus created by the first annular region was present across the central 30° of the retina. CONCLUSIONS: Some young adult myopes chronically experience high levels of hyperopic defocus when viewing near targets, which was replaced by myopic defocus in the annular part of the pupil covered by the treatment zones when fitted with a centre-distance myopia control DF CL.


Asunto(s)
Lentes de Contacto , Miopía , Acomodación Ocular , Humanos , Miopía/terapia , Refracción Ocular , Retina , Adulto Joven
18.
Clin Exp Optom ; 105(1): 41-47, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33689656

RESUMEN

Clinical relevance: Tear film assessment is essential in contact lens wearers and it can improve the success rates of the fitting.Background: To compare the short-term effect of two contact lenses on pre-lens tear film stability and comfort: dual-focus contact lens (MiSight) and a monofocal contact lens (Proclear 1-day).Methods: This randomised, double-masked, crossover study was performed in twenty-eight healthy, myopic volunteers aged between 18 and 32 years (23.5 ± 4.1 years). Only one randomly chosen eye was assessed. Distance vision and refraction were evaluated at baseline. Each contact lens type (monofocal and dual-focus) was randomly fitted, always in both eyes. A visual analogue scale between 0 and 10 was used to assess general comfort, physical comfort, and visual comfort. Tear Film Surface Quality (TFSQ) index, TFSQ_area and auto Tear Break-Up Time were obtained using Medmont E-300 at baseline (naked eye condition) and 25 minutes after each contact lens insertion.Results: Refractive sphere and cylinder were, respectively, -1.36 ± 1.04 D (ranging from -6.00 to -0.25 D) and -0.23 ± 0.30 D (ranging from -0.75 to 0.00 D). TFSQ and TFSQ area were lower (meaning more stable tear film) at baseline when compared with both contact lens types (p < 0.025). Higher pre-lens tear instability (larger TFSQ and_TFSQ area values) was found with the dual-focus than the monofocal lens. Auto Tear Break-Up Time was higher at baseline than with each of the contact lenses, without statistically significant differences between both contact lens types. Visual analogue scales revealed statistically significant better scores in the monofocal contact lens than in dual-focus contact lens for general (0.77 ± 1.14 vs 3.12 ± 2.79), physical (0.96 ± 1.46 vs 2.19 ± 2.45) and visual comfort (1.27 ± 1.66 vs 3.92 ± 2.04).Conclusion: A slight reduction in short-term pre-lens tear film stability was found in the dual-focus design in comparison with the monofocal lens, potentially contributing to the deterioration of visual performance and comfort during dual-focus contact lens wear.


Asunto(s)
Lentes de Contacto Hidrofílicos , Miopía , Adolescente , Adulto , Estudios Cruzados , Humanos , Miopía/terapia , Lágrimas , Adulto Joven
19.
Surg Endosc ; 36(7): 5032-5040, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34845549

RESUMEN

BACKGROUND AND AIMS: The Japan NBI Expert Team (JNET) classification is the first unified classification criteria for colorectal tumors using magnifying narrow-band imaging (NBI) in Japan. However, the diagnostic stratification ability of the JNET classification with dual-focus magnifying NBI (DF-JNET) has remained obscure. The aim of this study was to validate the diagnostic stratification ability of DF-JNET for colorectal tumors in two Japanese referral centers. METHODS: A multicenter retrospective image evaluation study was conducted by three experienced endoscopists, including an original JNET member who was also involved in establishing the diagnostic criteria. A total of two images, namely, one representative non-magnified white light image and one representative DF-NBI image for each of the 557 consecutive lesions were used in the evaluation study. The diagnostic value of DF-JNET was calculated based on the evaluation data. RESULTS: The sensitivity, specificity, positive and negative predictive values, and accuracy of DF-JNET Type 1 for differentiating between non-neoplastic and neoplastic lesions were 78.1%, 98.6%, 89.1%, 96.8%, and 95.9%, respectively; of Type 2A lesions for differentiating low-grade dysplasia from others were 98.0%, 76.5%, 94.9%, 89.7%, and 94.1%, respectively; of Type 2B lesions for differentiating high-grade dysplasia and shallow submucosal invasive carcinoma from others were 43.5%, 99.1%, 66.7%, 97.6%, and 96.8%, respectively; and of Type 3 lesions for differentiating deep submucosal invasive carcinoma from others were 83.3%, 99.5%, 62.5%, 99.8%, and 99.3%, respectively. CONCLUSIONS: All DF-JNET types had an over 90% diagnostic accuracy for the histological prediction of colorectal tumors. DF-JNET might contribute to appropriate treatment choices, such as endoscopic resection or surgery, not only in Japan but also in Western countries in which the use of optical zoom endoscopy is limited.


Asunto(s)
Carcinoma , Neoplasias Colorrectales , Colonoscopía/métodos , Neoplasias Colorrectales/diagnóstico por imagen , Neoplasias Colorrectales/patología , Humanos , Japón , Imagen de Banda Estrecha/métodos , Estudios Retrospectivos
20.
Lang Speech ; 64(2): 319-345, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31920161

RESUMEN

This paper investigates how French signals prominence in prosody in the post-verbal domain of sentences with two objects or two adjuncts that vary in information status and prosodic length. The information status of particular interest here is dual focus, defined as the presence of two foci in a mono-clausal sentence, but other information states are investigated as well. The controlled production experiment we report on allows for a detailed examination of prosodic prominence. High boundary tones at the end of non-final prosodic phrases are pervasive, as has been documented in many studies before the present one. An important but less documented result is the variation in different prosodic curs, in particular in the number and position of high tones, as well as the particular scaling relationship between them, providing a powerful tool for the expression of (dual) focus. We also report on a perception experiment with our data, showing a clear tendency for French listeners to select the intended context question, recognizing dual focus better than other information states. Overall, this article provides elements of answers as to why French prosody is so difficult to pin down, and why contradictory results and analyses have been proposed for this language.


Asunto(s)
Lenguaje , Percepción del Habla , Humanos
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