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Enrichment of soluble P on the surface layer of long-term no-till (NT) soils, and consequent increase in dissolved P losses, is a concern for which occasional plowing has been suggested as a remedy. We measured the effect of such strategic tillage (ST) on surface and subsurface P losses from 0.5-ha field plots on clay soil for 4 years. Two NT plots had discharged threefold dissolved molybdate-reactive P (DRP) losses compared to annually plowed soil conventional tillage (CT). ST by plowing to 20-cm depth was applied on one of the NT plots, whereas the other remained under NT. ST done in July was sown with canola (Brassica napus ssp. oleifera) to establish plant cover before winter. Summed 4-year DRP loss from ST treatment was 60% lower compared to NT (0.78 vs. 1.96 kg ha -1 ), accompanied with 11% higher particulate P (PP) loss (4.39 vs. 3.97 kg ha -1 ). CT plots produced slightly lower DRP losses (0.53-0.76 kg ha -1 ) than ST, but higher PP losses (6.02-7.96 kg ha -1 ). Bioavailable P (BAP) losses from ST were lower than from the other treatments if >7% of PP turns bioavailable. After ST, soil P stratification first vanished, but started to develop again when NT was resumed. Occasional tillage of NT soils mitigates DRP losses over several years, and it was at the study site the preferred mitigation option in reducing BAP losses., (© 2024 The Author(s). Journal of Environmental Quality published by Wiley Periodicals LLC on behalf of American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)

Purpose: To describe the optical coherence tomography features of vitamin A deficiency., Methods: Case series includes three male patients aged 50 to 66 years with vitamin A deficiency and visual symptoms ranging from 2 to 8 months. Examination included optical coherence tomography (OCT), fundus autofluorescence imaging, full-field electroretinography6 and laboratory work-up., Results: Patient 1 had inoperable pancreatic neuroendocrine tumor and presented with worsening nyctalopia. The electroretinography showed absent rod function 2 months after the onset of symptoms, followed by a decrease of the cone function eight months after the onset. Optical coherence tomography showed poorly distinguishable outer segments of the photoreceptors with the disappearance of the interdigitation zone. At that time, vitamin A deficiency along with several other deficiencies was confirmed. After the initiation of parenteral nutrition, a substantial improvement of the patient's overall well-being was noted and the OCT showed normalization of the retinal structure. Two other patients were diagnosed with vitamin A deficiency based on similar OCT features., Conclusion: Disruption of the outer segments of the photoreceptors and the disappearance of the interdigitation zone on OCT may be helpful in recognition of vitamin A deficiency. Early detection and malnutrition evaluation are especially important in patients with a history of gastrointestinal disorders who may have several other underlying deficiencies. Treatment with either enteral or parenteral nutrition not only leads to resolution of visual symptoms but vastly improves their general condition and quality of life., (Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the Opthalmic Communications Society, Inc.)

Recognising a potential visual-field (VF) defect in paediatric patients might be challenging, especially in children before the age of 5 years and those with developmental delay or intellectual disability. Visual electrophysiological testing is an objective and non-invasive technique for evaluation of visual function in paediatric patients, which can characterise the location of dysfunction and differentiate between disorders of the retina, optic nerve and visual pathway. The recording of electroretinography (ERG) and visual-evoked potentials (VEP) is possible from early days of life and requires no subjective input from the patient. As the origins of ERG and VEP tests are known, the pattern of electrophysiological changes can provide information about the VF of a child unable to perform accurate perimetry. This review summarises previously published electrophysiological findings in several common types of VF defects that can be found in paediatric patients (generalised VF defect, peripheral VF loss, central scotoma, bi-temporal hemianopia, altitudinal VF defect, quadrantanopia and homonymous hemianopia). It also shares experience on using electrophysiological testing as additional functional evidence to other tests in the clinical challenge of diagnosing or excluding VF defects in complex paediatric patients. Each type of VF defect is illustrated with one or two clinical cases., (© 2021. The Author(s).)

Mutations in RPGR ORF15 are associated with rod-cone or cone/cone-rod dystrophy, the latter associated with mutations at the distal end. We describe the phenotype associated with a novel variant in the terminal codon of the RPGR ORF15 c.3457T>A (Ter1153Lysext*38), which results in a C-terminal extension. Three male patients from two families were recruited, aged 31, 35, and 38 years. Genetic testing was performed by whole exome sequencing. Filtered variants were analysed according to the population frequency, ClinVar database, the variant's putative impact, and predicted pathogenicity; and were classified according to the ACMG guidelines. Examination included visual acuity (Snellen), colour vision (Ishihara), visual field, fundus autofluorescence (FAF), optical coherence tomography (OCT), and electrophysiology. All patients were myopic, and had central scotoma and reduced colour vision. Visual acuities on better eyes were counting fingers, 0.3 and 0.05. Electrophysiology showed severely reduced cone-specific responses and macular dysfunction, while the rod-specific response was normal. FAF showed hyperautofluorescent ring centred at the fovea encompassing an area of photoreceptor loss approximately two optic discs in diameter (3462-6342 μm). Follow up after 2-11 years showed enlargement of the diameter (avg. 100 μm/year). The novel c.3457T>A (Ter1153Lysext*38) mutation in the terminal RPGR ORF15 codon is associated with cone dystrophy, which corresponds to the previously described phenotypes associated with mutations in the distal end of the RPGR ORF15 . Minimal progression during follow-up years suggests a relatively stable disease after the initial loss of the central cones.

Mutations in rhodopsin gene ( RHO ) are a frequent cause of retinitis pigmentosa (RP) and less often, congenital stationary night blindness (CSNB). Mutation p.G90D has previously been associated with CSNB based on the examination of one family. This study screened 60 patients. Out of these 60 patients, 32 were affected and a full characterization was conducted in 15 patients. We described the clinical characteristics of these 15 patients (12 male, median age 42 years, range 8-71) from three families including visual field (Campus Goldmann), fundus autofluorescence (FAF), optical coherence tomography (OCT) and electrophysiology. Phenotypes were classified into four categories: CSNB ( N = 3, 20%) sector RP ( N = 3, 20%), pericentral RP ( N = 1, 6.7%) and classic RP ( N = 8, 53.3% (8/15)). The phenotypes were not associated with family, sex or age (Kruskal-Wallis, p > 0.05), however, cystoid macular edema (CME) was observed only in one family. Among the subjects reporting nyctalopia, 69% (22/32) were male. The clinical characteristics of the largest p.G90D cohort so far showed a large frequency of progressive retinal degeneration with 53.3% developing RP, contrary to the previous report.

Purpose: Chromatic visual evoked potentials (cVEP) primarily reflect the parvocellular visual pathway function, which has been shown to be predominantly affected in demyelinating disease (DD). The purpose of this study was to evaluate cVEP responses and to compare them with other structural and functional findings in young patients with DD., Methods: Thirty patients (8-28 years of age) with DD with or without a history of optic neuritis (ON) were investigated. Twenty-five eyes had at least one episode of ON (ON-group) and 35 eyes had no clinically evident episode of ON (nON-group). OCT imaging was performed using a high-resolution spectral-domain OCT (SD-OCT), measuring retinal nerve fiber layer (RNFL) thickness. Pattern reversal electroretinography (PERG) and visual evoked potentials (VEP) were recorded according to the ISCEV standard, and chromatic visual evoked potentials (cVEP) were recorded to isoluminant red-green (R-G) and blue-yellow (B-Y) 7° circle stimuli, composed of horizontal sinusoidal gratings with spatial frequency 2 cycles/°, 90% chromatic contrast and onset-offset (300:700 ms) mode of stimulation. Structural and functional measures were analyzed and compared between the groups., Results: Both general (G) and temporal (T) RNFL thicknesses were reduced below normal limits in most of the eyes. However, in the ON-group (G: 77.5 ± 20.6, T: 51.4 ± 23.4 µm), the thinning was more significant (p < 0.001) than in the nON-group (G: 95.4 ± 12.1, T: 70.1 ± 11.5 µm). PERG N95 was within normal limits in the nON-group, while it was significantly more affected in the ON-group (7.4 ± 1.0 vs. 5.1 ± 2.0 μV; p < 0.0001). Similarly, also VEP P100 latency and amplitude showed a greater percentage of abnormality in the ON-group, the latency being longer (117.2 ± 16.9 vs. 99.4 ± 4.6 ms; p < 0.0001) and the amplitude lower (9.1 ± 5.1 vs. 16.4 ± 7.5 μV; p < 0.0001). The cVEP N-wave amplitude to R-G and B-Y stimuli was reduced below normal limits in both ON- and nON-groups; however, cVEP to B-Y stimulation were slightly more affected in the ON-group (4.0 ± 3.8 vs. 5.9 ± 3.3 µm; p = 0.02). A positive correlation between cVEP amplitude and RNFL thickness and between cVEP amplitude and PERG N95 amplitude, as well as a strong negative correlation between cVEP amplitude and P100 latency was observed., Conclusions: These findings demonstrate that cVEP indicate early abnormality of parvocellular pathway function in eyes with or without a history of optic neuritis and can be used together with other structural and functional parameters to evaluate visual pathway integrity of young patients with DD.

Purpose: Assessment of multifocal ERG (mfERG) changes in patients treated with chloroquine and their correlation with morphological abnormalities, detected by spectral-domain optical coherence tomography in relation to cumulative dosage., Methods: Data from 37 eyes of 20 patients were retrospectively collected, and one randomly selected eye per patient was considered for statistical analysis. Eyes were divided into three groups according to mfERG and visual acuity findings: normal, early and advanced maculopathy. Functional measures of the first three mfERG rings were compared with retinal thickness measures of the corresponding OCT ETDRS circles. Data on cumulative dose and duration of therapy were also evaluated., Results: The mean mfERG values progressively decreased according to the stage of the disease. In particular in the early maculopathy group, amplitudes were significantly reduced in all the three central rings. The mean ring ratio R1/R2 was abnormal only in the early maculopathy group. OCT thickness measures were significantly lower in all the three ETDRS circles in the advanced maculopathy group, and in the paracentral circle in the early maculopathy group. Considering all the eyes, there was a statistically significant correlation between functional and morphological values (p < 0.001). High chloroquine cumulative dosages were always associated with retinal toxic effects, whereas lower cumulative dosages generated different levels of toxicity., Conclusions: This study shows a strong association between mfERG ring values and the corresponding OCT thickness measures; however, mfERG may enhance early detection of functional changes in patients treated with chloroquine, especially in ambiguous cases. At low chloroquine cumulative dosages, different subjects might have different susceptibilities to the drug.

USH2A mutation is the most common cause of retinitis pigmentosa, with or without hearing impairment. Patients most commonly exhibit hyperautofluorescent ring on fundus autofluorescence imaging (FAF) and rod-cone dystrophy on electrophysiology. A detailed study of three USH2A patients with a rare pattern of double hyperautofluorescent rings was performed. Twenty-four patients with typical single hyperautofluorescent rings were used for comparison of the ages of onset, visual fields, optical coherence tomography, electrophysiology, and audiograms. Double rings delineated the area of pericentral retinal degeneration in all cases. Two patients exhibited rod-cone dystrophy, whereas the third had a cone-rod dystrophy type of dysfunction on electrophysiology. There was minimal progression on follow-up in all three. Patients with double rings had significantly better visual acuity, cone function, and auditory performance than the single ring group. Double rings were associated with combinations of null and missense mutations, none of the latter found in the single ring patients. According to these findings, the double hyperautofluorescent rings indicate a mild subtype of USH2A disease, characterized by pericentral retinal degeneration, mild to moderate hearing loss, and either a rod-cone or cone-rod pattern on electrophysiology, the latter expanding the known clinical spectrum of USH2A-retinopathy., Competing Interests: The authors declare no conflict of interest.

Purpose: The purpose of this study was to compare electroretinographic (ERG) responses of preterm schoolchildren, with and without a history of retinopathy of prematurity (ROP) with those of full-term schoolchildren by using a portable ERG device (RETeval system)., Methods: Twenty five prematurely born schoolchildren with a mean gestational age of 27 + 1/7w (range 23-30w) and a mean birth weight of 1030 g (range 580-1700 g) who were 6.9 ± 2.2 years old participated in the study (premature group). A further subdivision according to a history of ROP (ROP+ group) or its absence (ROP- group) was introduced. Twenty eight healthy full-term schoolchildren with an average age of 8.6 ± 1.9 years participated as the control group. 30-Hz flicker ERG responses were obtained, and implicit times and amplitudes were compared between the groups., Results: 30-Hz flicker ERG implicit times showed a significant difference between all three groups of children. The mean value of the implicit time in the term group was 25.76 ± 0.9 ms, whereas in the preterm ROP + group it was 28.96 ± 1.0 ms and in the preterm ROP- group it was 26.87 ± 1.5 ms. 30-Hz flicker ERG amplitudes did not show significant difference between term children and children born prematurely with or without ROP., Conclusions: Prematurely born schoolchildren exhibit longer implicit time of the 30-Hz flicker ERG response compared to controls, suggesting a possible abnormality of the retinal cone system function. Under such circumstances, portable ERG device might be used clinically as a screening tool for retinal function evaluation in prematurely born children.

Purpose: To evaluate intravitreal bevacizumab (IVB) treatment in patients with central retinal vein occlusion (CRVO) by spectral domain optical coherence tomography (OCT) and electroretinography (ERG)., Methods: Twenty-two CRVO patients were treated with IVB injections and followed for 1 year. Morphological effect of treatment was observed with fluorescent angiography and OCT. Functional effect was followed with best corrected visual acuity (BCVA) and ERG: combined rod-cone response of the standard full-field ERG (dark adapted 3.0 ERG), photopic negative response (PhNR), and pattern ERG (PERG)., Results: Best corrected visual acuity (BCVA) improved by 18.2 letters after 6 months (p ≤ 0.001) and additional 4.7 letters by the 12th month (p ≤ 0.001). The central retinal thickness of 829.8 ± 256.7 μm decreased to 398.8 ± 230 μm (p ≤ 0.001) after 6 months and to 303.7 ± 128.9 μm during the following 6 months (p ≤ 0.001). The total macular volume (14.4 ± 4.2 mm(3)) decreased to 9.6 ± 3.2 mm(3) and 8.5 ± 2.0 mm(3) after 6 months and 1 year of treatment, respectively (p ≤ 0.001). Electrophysiological measures improved significantly after 6 months and 1 year of treatment: the a-wave implicit time of dark adapted 3.0 ERG from 25.6 ± 2.3 to 24.1 ± 2.1 and 24.1 ± 2.0 ms (p ≤ 0.01); the PhNR from -5.9 ± 6.6 to -9.4 ± 6.1 and -10.4 ± 4.6 µV (p ≤ 0.05); the PERG P50 amplitude from 0.2 ± 0.3 to 0.9 ± 0.6 and 1.1 ± 0.6 µV (p ≤ 0.001); and N95 amplitude from 0.4 ± 0.6 to 1.2 ± 0.9 and 1.6 ± 0.9 µV (p ≤ 0.001)., Conclusions: Intravitreal bevacizumab (IVB) treatment of macular edema due to CRVO improved standard morphological measures and the electrophysiological function of outer and inner retinal layers, which was most evident in central retina.