Evidence map›Paper›PMID 40247207›Full record

ArticleBMC ophthalmology2025

Studying the effect of keratoconus severity on the accuracy of intraocular lens power calculation using newer keratoconus-specific formulas.

Hany Ahmed Helaly, Tamer Moussa Ibrahim, Mohamed Sobhy Hassan, Mohamed Sobhy El-Mansy

Abstract read
In one paragraph

Article in BMC ophthalmology, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

0numbers the graph read from it
0cells of the map it votes in
3citing 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.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

3 citing papers in PubMed.

  1. Article
  2. Article
  3. Review
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

4 authors.

Hany Ahmed HelalyOphthalmology Department, Faculty of Medicine, Alexandria University, Alexandria, Egypt. hany209209@yahoo.com.
Tamer Moussa IbrahimOphthalmology Department, Faculty of Medicine, Alexandria University, Alexandria, Egypt.
Mohamed Sobhy HassanOphthalmology Department, Faculty of Medicine, Alexandria University, Alexandria, Egypt.
Mohamed Sobhy El-MansyOphthalmology Department, Faculty of Medicine, Alexandria University, Alexandria, Egypt.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeto study the effect of keratoconus severity on the accuracy of intraocular lens power calculation using newer keratoconus (KC) specific formulas.

methodsThis was a retrospective case series that included 99 eyes from 99 patients. The included patients were further subdivided into 3 groups according to keratoconus severity. The results of various IOL power calculation formulas were analyzed in this study. Two KC specific formulas were employed: Barrett True K KC and Kane KC. Additionally, the following formulas were utilized: Barrett Universal II (BUII), EVO 2.0, Hoffer QST, Kane, and PEARL-DGS.

resultsThe Kane KC was the only formula to show a myopic mean prediction error (- 0.76 ± 1.06 D). BUII and Barrett True K KC formulas showed the least mean and median absolute errors. The median absolute error (MedAE) for BUII and Barrett True K KC was 0.34 and 0.35 D respectively. BUII and Barrett True K KC formulas had the highest cases within ± 0.25 D of the intended refraction (42.42% and 39.39%, respectively). In severe KC eyes, the MedAE for Barrett True K KC and BUII formulas was 0.56 and 0.46 D respectively. In severe KC eyes, Barrett True K KC and BUII formulas showed the highest cases within ± 0.25 D of the intended refraction (27.27% and 27.27%, respectively).

conclusionmost non KC specific IOL power calculation formulas perform in an acceptable way in mild KC eyes. In moderate and severe KC eyes, the KC specific formulas perform better than the standard formulas. Barrett True K KC formula performed better than Kane KC in moderate and severe KC eyes. BUII formula was the best performing non KC specific formula in moderate and severe KC eyes.

Indexed as

KeratoconusLenses, IntraocularOptics and PhotonicsRefraction, OcularAdultBiometryCorneal TopographyFemaleHumansMaleMiddle AgedRetrospective StudiesSeverity of Illness IndexVisual AcuityYoung AdultARGOSBarrett true K KCBiometryIOL power calculationKane KCKeratoconusSum-of-segments

Identifiers

PMID40247207
PMCPMC12004648

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

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 OpenQuestion graph.