Pearls of meta-analyses and systematic review in scientific evidence.

Scientific evidence develops bit by bit from case reports, case series; to larger case-control, case-cohort; and further escalate to randomized controlled trials. This echoed the importance of continue publishing World journal of Clinical Cases, where novel and advancing discoveries start from a single case. In contrast, at the other end of the realm of evidence synthesis, systematic review and meta-analysis represent distinct yet interconnected processes. Butorphanol in epidural labor analgesia has long been studied since 1989, and with 70 publications from MEDLINE searches. However, there was no meta-analysis, nor any systematic review published so far. The latest in-press article published by Tang et al. on the protocol for the systematic review and meta-analysis on the safety and effectiveness of butorphanol in epidural labor analgesia is encouraging. We believe the findings of this study will be valuable for clinical practice as well as for future research.

Retinal Vein Occlusion after COVID-19 Vaccination-A Review.

Background Retinal vein occlusion (RVO) occurring after COVID-19 vaccination has been reported worldwide. Such a sight-threatening condition occurring after COVID-19 vaccination is a menace to ophthalmic health. This article reviews current evidence related to post-COVID-19 vaccination RVO. Method A total of 29 relevant articles identified on PubMed in January 2023 were selected for review. Observation All cases presented to ophthalmologists with visual loss shortly after COVID-19 vaccination. Mean and median age were both 58. No sex predominance was observed. RVO was diagnosed from findings on dilated fundal examination and ophthalmic imaging. AstraZeneca and BNT vaccines accounted for most cases. Vascular risk factors, e.g., diabetes mellitus and hypertension, were common. Most laboratory tests requested came back unremarkable. Most patients responded well to standard treatment, except those with ophthalmic comorbidities. Visual prognosis was excellent on short-term follow-up. Discussion The causality between RVO and COVID-19 vaccination is undeterminable because of the nature of articles, heterogenous reporting styles, contradicting laboratory findings and co-existing vascular risk factors. Vaccine-induced immune thrombotic thrombocytopenia, retinal vasculitis and homocysteinaemia were proposed to explain post-vaccination RVO. Large-scale studies have demonstrated that the incidence of RVO following COVID vaccination is very low. Nevertheless, the effects of boosters on retinal vasculature and ophthalmic health are still unclear. Conclusions The benefits of COVID-19 vaccination are believed to outweigh its ophthalmic risks. To ensure safe vaccination, the prior optimisation of comorbidities and post-vaccination monitoring are important. COVID-19 vaccines (including boosters) should be offered with reasonable confidence. Further studies are warranted to elucidate the ophthalmic impact of vaccines.

Glaukomflecken: The classic and uncommon ocular sign after acute primary angle closure attack.

The widespread of upper respiratory tract symptoms caused by COVID-19 infections has increased the prescription and usage of antitussive and nasal decongestants. We presented a case of ocular acute primary angle closure attack with increased intraocular pressure after COVID-19 therapy. Glaukomflecken, the classic and uncommon ocular sign after acute primary angle closure attack, was demonstrated in this visual case discussion.