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Energetic electron injections can generate or amplify electromagnetic waves such as whistler-mode waves. These waves can resonantly interact with available particles to affect their equatorial pitch angle. This process can be considered as a diffusion that scatters particles into the loss cone. This study investigates whistler-mode wave generation in conjunction with electron injections using in situ wave measurements by the Time History of Events and Macroscale Interactions during Substorms mission during 2011-2020. We characterize the whistler-mode wave behavior associated with 733 selected dispersionless electron injections and dipolarizing flux bundles (DFBs). We observe intense wave activity and strong diffusion associated with only the top 5% and 10% of the selected injection events, respectively. We also study the wave activity when there is a sharp rise in the northward component of the magnetic field around the injection time (DFBs). In this case, the generated wave powers increase, and the power change is at least two times greater than non-DFB injections.

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PurposeTo investigate intraoperative anterior segment optical coherence tomography (AS-OCT) to compare pachymetry changes between two methods (group 1: speculum-on, group 2: speculum-off during riboflavin instillation stage) during corneal cross-linking /CXL) (9 mW/cm2 for 10 min) in keratoconic patients.MethodsIn this interventional case series, 11 eyes (11 patients) in group 1 and 14 eyes (14 patients) in group 2 were enrolled. Pachymetry measurements by spectral domain OCT was performed at baseline, after epithelial removal, after 30 min of imbibition with riboflavin, and after UV irradiation. Repeated measures analysis of variance was used to compare the trend of changes in different stages of the procedure within and between two groups.ResultsThe corneal thinnest pachymerty (CTP) at baseline, after epithelial removal, 30 min of riboflavin instillation, and irradiation was 469.8±26.5, 438.0±27.1, 354.3±28.4, 367.1±31.8 microns in group 1 and 463.2±25.1, 438.0±27.1, 421.6±54.0, 386.9±34.0 microns in group 2, respectively. Group 1 showed a significantly greater decrease in the corneal pachymetry (P<0.001) during riboflavin instillation, while in group 2 a greater decrease in CTP was observed during the UV irradiation phase (P=0.002).ConclusionsUsing the intraoperative OCT, the speculum-off group had a more stable corneal pachymetry during riboflavin instillation time. Despite this, the effect was not lasting throughout the procedure; significant changes were noted in the corneal pachymetry at the end of operation in both groups; further highlighting the limitations imposed by corneal stromal shrinkage using isotonic dextran containing riboflavin solution for CXL.

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PURPOSE: To evaluate the efficacy and safety of Artisan-Verysise intraocular lens (IOL) secondarily implanted for aphakic correction in post-traumatic vitrectomized eyes. METHODS: Postoperative outcomes of secondary implantation of an iris-supported Artisan IOL in 17 unilateral aphakic patients with previous pars plana vitrectomy secondary to posterior segment trauma were evaluated prospectively. Eyes had vitrectomized in previous 6-60 months. After complete ophthalmologic examination, IOL implantation was performed through a scleral tunnel incision. Patients were followed for visual outcome, endothelial cell density (ECD) and occurrence of complications. Uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), spherical equivalents (SE), and ECD were compared before and after IOL insertion. RESULTS: Patients' postoperative mean follow-up were 14.65+/-5.21 months. UCVA improved in all patients. (0.03+/-0.1 preoperatively vs 0.45+/-0.29 postoperatively, P=0.0001). However improvement of BCVA was not significant. Mean postoperative SE was 0.84+/-1.32 D, whereas it was 10.85+/-1.70 D preoperatively (P=0.0001). SE was within +/-2.00 D of emmetropia in 16 eyes (94.1%). Mean endothelial cell loss was 8.1% in first 6 postoperative months.All eyes achieved the desired anatomic results. No intraoperative complications occurred in any of our cases. Complications were transient pigmented precipitates (three cases), choroidal detachment (one case), and transient vitreous haemorrhage (one case). CONCLUSION: Secondary Artisan IOL implantation is an effective and safe procedure to correct aphakia in vitrectomized eyes without capsular support after trauma. Considering good visual rehabilitation and low rate of complications, this procedure is recommended in vitrectomized eyes.

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