Introduction Human coronavirus (HCoVs) are a group of viruses with recognized neurotropic and neuroinvasive capabilities. The reports on the neurological and ocular findings are increasing day after day and several central and peripheral neurological manifestations are already described. However, none specifically describes the neuro-ophthalmological manifestation of HCoVs. This is the first article specifically reviewing neuro-ophthalmological manifestations of HCoVs infection. Methods PubMed and Google Scholar databases were searched using the keywords: coronaviridae, coronavirus, COVID-19, SARS-CoV-2, SARS-CoV-1, MERS, ocular, ophthalmology, ophthalmological, neuro-ophthalmology, neurological, manifestations. A manual search through the reference lists of relevant articles was also performed. There were no restrictions concerning language or study type and publications not yet printed but available online were considered. Results Coronavirus eye involvement is not frequent and includes mostly a typical viral follicular conjunctivitis. Recently, retinal anatomical alterations were described using optic coherence tomography. Neuro-ophthalmological symptoms and signs can appear isolated or associated with neurological syndromes. The manifestations include headache, ocular pain, visual impairment, diplopia, and cranial nerve palsies secondary to Miller Fisher syndrome, Guillain-Barré syndrome, or encephalitis, and nystagmus. Conclusion Neurological and neuro-ophthalmological syndromes, symptoms, and signs should not be neglected and a complete ophthalmological examination of these patients should be performed to fully describe ocular manifestations related to HCoVs. We believe that major ocular and neuro-ophthalmological manifestations reports lack due to safety issues concerning detailed ophthalmological examination; on the other hand, in a large number of cases, the presence of life-threatening coronavirus disease hinders ocular examination and ophthalmologist’s visit to the intensive care unit.

Purpose To compare the accuracy of a newly developed intraocular lens (IOL) power formula (VRF-G) with twelve existing formulas (Barret Universal II, EVO 2.0, Haigis, Hill-RBF 2.0, Hoffer Q, Holladay 1, Kane, Næeser 2, PEARL-DGS, SRK/T, T2 and VRF). Methods Retrospective case series including 828 patients having uncomplicated cataract surgery with the implantation of a single IOL model (SN60WF). Using optimised constants, refraction prediction error of each formula was calculated for each eye. Subgroup analysis was performed based on the axial length (short ≤22.0mm; medium >22.0mm to <26.0mm; long ≥26.0mm). Main outcomes included mean prediction error (ME) mean (MAE) and median absolute error (MedAE), in diopters (D), and the percentage of eyes within ±0.25D, ±0.50D, ±0.75D and ±1.00D. Results Formulas absolute errors were statistically different among them (p<0.001), with Kane having the lowest MAE of all formulas, followed by EVO 2.0 and VRF-G, which had the lowest MedAE. The Kane formula had the highest percentage of eyes within ±0.25D (47.0%) and ±1.00D (97.7%) and the VRF-G formula had the highest percentage of eyes within ±0.50D (79.5%). For all AL subgroups, Kane, EVO 2.0 and VRF-G formulas had the most accurate performances (lowest MAE). Conclusion New generation formulas may help us in achieving better refractive results, lowering the variance in accuracy in extreme eyes – Kane, EVO 2.0 and VRF-G formulas are promising candidates to fulfil that goal.

Background/AimsTo investigate the influence of anterior chamber depth (ACD) and lens thickness (LT) on 9 intraocular lens (IOL) power calculation formulas accuracy, in patients with normal axial lengths.MethodsRetrospective case series, including patients having uncomplicated cataract surgery with insertion of a single IOL model, divided into three groups according to preoperative ACD. Each group was further subdivided into three subgroups, according to the LT. Using optimised constants, refraction prediction error was calculated for Barrett Universal II, Emmetropia Verifying Optical (EVO) V.2.0, Haigis, Hill-RBF V.2.0, Hoffer Q, Holladay 1, Kane, PEARL-DGS and SRK/T formulas. Mean prediction error, mean and median absolute error (MedAE) and the percentage of eyes within ±0.25D, ±0.50D and ±1.00D were also calculated.ResultsThe study included 695 eyes from 695 patients. For ACD ≤3.0 mm and ≥3.5 mm, mean prediction error of SRK/T, Hoffer Q and Holladay 1 was significantly different from 0 (p<0.05). PEARL-DGS, Kane, EVO V.2.0 and Barrett Universal II were more accurate than the Hoffer Q in ACD ≤3.0 mm (p<0.05). Kane, PEARL-DGS, EVO V.2.0 and Barrett Universal II revealed the lowest variance of mean and MedAE by ACD and LT subgroup. Haigis and Hill-RBF V.2.0 were significantly influenced by LT, independently of the ACD, with a myopic shift with thin lenses and a hyperopic shift with thick lenses (p<0.05).ConclusionNew generation formulas, particularly Kane, PEARL-DGS and EVO V.2.0, seem to be more reliable and stable even in eyes with extreme ACD-LT combinations.

No abstract

Background Our study aimed to assess and compare the accuracy of 8 intraocular lens (IOL) power calculation formulas (Barrett Universal II, EVO 2.0, Haigis, Hoffer Q, Holladay 1, Kane and PEARL-DGS) in patients submitted to combined phacovitrectomy for vitreomacular (VM) interface disorders. Methods Retrospective chart review study including axial-length matched patients submitted to phacoemulsification alone (Group 1) and combined phacovitrectomy (Group 2). Using optimized constants in both groups, refraction prediction error of each formula was calculated for each eye. The optimised constants from Group 1 were also applied to patients of Group 2 – Group 3. Outcome measures included the mean prediction error (ME) and its standard deviation (SD), mean (MAE) and median (MedAE) absolute errors, in diopters (D), and the percentage of eyes within ± 0.25D, ± 0.50D and ± 1.00D. Results A total of 220 eyes were included (Group 1: 100; Group 2: 120). In Group 1, the difference in formulas absolute error was significative (p = 0.005). The Kane Formula had the lowest MAE (0.306) and MedAE (0.264). In Group 2, Kane had the overall best performance, followed by PEARL-DGS, EVO 2.0 and Barrett Universal II. The ME of all formulas in both Groups 1 and 2 were 0.000 (p = 0.934; p = 0.971, respectively). In Group 3, a statistically significant myopic shift was observed for each formula (p < 0.001). Conclusion Surgeons must be careful regarding IOL power selection in phacovitrectomy considering the systematic myopic shift evidenced—constant optimization may help eliminating such error. Moreover, newly introduced formulas and calculation methods may help us achieving increasingly better refractive outcomes both in cataract surgery alone and phacovitrectomy.