Evidence map›Paper›PMID 40835236›Full record

Observational studyBMJ open ophthalmology2025

Comparative analysis of iris blood flow after first-eye and second-eye cataract surgeries: insights into increased pain perception in the second eye.

Jitong Zhou, Yuxi Chen, Jiaqi Meng, Kaiwen Cheng, Jiao Qi, Yu Du, Yunqian Yao, Yi Lu, Wenwen He, Xiangjia Zhu

Registry-linked trialAbstract readComparative StudyObservational Study
In one paragraph

Observational study in BMJ open ophthalmology, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT02182921 (Evaluation of Surgical Outcomes of Cataract Surgery), which is not on this map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

NCT02182921 recruitingnot on this map

Evaluation of Surgical Outcomes of Cataract Surgery

TypeobservationalSponsorEvidence Based Cataract Study GroupRan2013 to 2030Enrolled20,000ConditionsCataract, High Myopia
3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors.

Jitong ZhouDepartment of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai, China.
Yuxi ChenDepartment of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai, China.
Jiaqi MengDepartment of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai, China.
Kaiwen ChengDepartment of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai, China.ORCID 0000-0002-1629-3229
Jiao QiDepartment of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai, China.
Yu DuDepartment of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai, China.
Yunqian YaoDepartment of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai, China.
Yi LuDepartment of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai, China zhuxiangjia1982@126.com hewenwen@fudan.edu.cn luyieent@126.com.
Wenwen HeDepartment of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai, China zhuxiangjia1982@126.com hewenwen@fudan.edu.cn luyieent@126.com.
Xiangjia ZhuDepartment of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai, China zhuxiangjia1982@126.com hewenwen@fudan.edu.cn luyieent@126.com.ORCID 0000-0001-5588-1667

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveTo investigate quantitative changes in iris blood flow after first-eye and second-eye cataract surgeries, and their correlation with increased pain in the second eye. METHODS AND ANALYSIS: In this prospective study, 88 eyes of 44 participants who underwent uneventful cataract surgery were followed up at enrolment, 1 day before, and 1 day, 1 week and 1 month after each eye surgery. Iris blood flow was quantified by a swept-source optical coherence tomography angiography and intraoperative pain was evaluated. Participants were divided into three groups according to time intervals between two eye surgeries: ≥1 to <2 weeks (short interval), ≥2 to ≤4 weeks (medium interval) and greater than 4 weeks (long interval).

resultsThe second eye experienced two significant increases in iris blood flow following cataract surgery: one after the first eye and the other after its own, with the latter being significantly higher than the increase observed in the operated eye after the first surgery (p<0.05). Additionally, the second eye showed higher iris blood flow density in the short interval group compared with the long and medium at specific time points (p<0.05). The bilateral pain index difference positively correlated with second eye iris blood flow density (p<0.05) and was significantly greater in the short interval group than the long interval group (p<0.05).

conclusionsIris blood flow increased in the second-operated eye post surgery compared with the first eye, which may correlate to second-eye pain. However, due to the variability in individual pain perception, a larger sample size is needed to prospectively validate our findings to improve their generalisability. TRIAL REGISTRATION NUMBER: NCT02182921.

Indexed as

Cataract ExtractionIrisPain PerceptionPostoperative PainRegional Blood FlowAgedAged, 80 and overFemaleFluorescein AngiographyFollow-Up StudiesHumansMaleMiddle AgedPain MeasurementProspective StudiesTomography, Optical CoherenceImagingInflammationLens and zonulesTreatment Surgery

Identifiers

PMID40835236
PMCPMC12374657

What Socratic holds

Textmetadata
LicenceCC BY-NC
Read underepoch 390

Registered trials

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.