Evidence map›Paper›PMID 37861937›Full record

ArticleInternational ophthalmology2023

Intraocular pressure after combined photorefractive keratectomy and corneal collagen cross-linking for keratoconus.

Karim Mahmoud Nabil, Ahmed Abdel Karim Elmassry, Silas Ntakarusho, Amr Ahmed Said

Abstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in International ophthalmology, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing 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

2 citing papers in PubMed.

  1. Review
  2. Intraocular pressure measurement in keratoconus: a narrative review.International journal of ophthalmology · 2026
    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.

Karim Mahmoud NabilDepartment of Ophthalmology, Faculty of Medicine, University of Alexandria, Postal Code 21523, 19 Amin Fekry Street, Raml Station, Alexandria, Egypt. Karim_nabil_ophth@yahoo.com.
Ahmed Abdel Karim ElmassryDepartment of Ophthalmology, Faculty of Medicine, University of Alexandria, Postal Code 21523, 19 Amin Fekry Street, Raml Station, Alexandria, Egypt.
Silas NtakarushoDepartment of Ophthalmology, University of Ngozi, Ngozi, Burundi.
Amr Ahmed SaidDepartment of Ophthalmology, Faculty of Medicine, University of Alexandria, Postal Code 21523, 19 Amin Fekry Street, Raml Station, Alexandria, Egypt.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeThe purpose of this prospective study was to evaluate the effect of combined photorefractive keratectomy (PRK) and corneal collagen cross-linking (CXL) on intraocular pressure (IOP) in patients with keratoconus (KC).

methodsWe included 64 eyes of 34 patients (19 males and 15 females; age: 19-40y) with stages 1-2 keratoconus which had undergone combined wavefront-optimized photorefractive keratectomy and corneal collagen cross linking. Two other groups of patients were added as controls: the PRK group including 110 eyes of 57 patients (23 males and 34 females; age: 18-44y) which had undergone wavefront-optimized photorefractive keratectomy for myopic refractive errors, and the CXL group including 36 eyes of 23 patients (14 males and 9 females; age: 12-38y) with keratoconus, not filling the inclusion criteria for combined PRK and CXL, which had undergone corneal collagen cross-linking. IOP was recorded preoperatively and postoperatively at 3, 6 and 12 months follow-up visits.

resultsPreoperative IOP in both CXL (12.1 ± 2.53 mmHg) and PRK + CXL (13.2 ± 2.50 mmHg) groups was significantly lower than PRK group (15.8 ± 3.10 mmHg) (F = 30.505, p < 0.001). At 3 months postoperatively, IOP showed no statistically significant difference between the three studied groups (F = 1.821, p = 0.164). At 6 months postoperatively, IOP in the CXL group (14.6 ± 2.64 mmHg) was significantly higher than both PRK (13.4 ± 2.27 mmHg) and PRK + CXL (13.3 ± 2.62 mmHg) groups (F = 3.721, p = 0.026). At 12 months postoperatively, IOP in the CXL group (14.3 ± 2.69 mmHg) was significantly higher than the PRK group (13.2 ± 2.23 mmHg) and was higher than PRK + CXL group (13.3 ± 2.59 mmHg) although not statistically significant (F = 3.393, p = 0.035). Regarding the percent of change from preoperative IOP, a statistically significant difference between the three studied groups was detected at 3, 6 and 12 months postoperatively (H = 117.459, 109.303, 122.694 respectively, p < 0.001). The median percent of change from preoperative IOP in the PRK group was -16.7%, -15%, and -16.7%, in the CXL group was + 14.3%, + 19.4%, and + 19.1%, while in PRK + CXL group was 0% at 3, 6 and 12 months postoperatively. (Post-hoc power analysis 75%).

conclusionsCombined PRK and CXL in patients with KC shows no significant effect on IOP, in contrast to either procedure performed separately.

Indexed as

KeratoconusPhotorefractive KeratectomyAdolescentAdultChildCorneaCorneal Cross-LinkingCorneal TopographyCross-Linking ReagentsFemaleHumansIntraocular PressureMalePhotosensitizing AgentsProspective StudiesRiboflavinCross-Linking ReagentsPhotosensitizing AgentsRiboflavinCorneal collagen cross linkingIntraocular pressureKeratoconusPhotorefractive keratectomy

Identifiers

PMID37861937
PMCPMC10724307

What OpenQuestion holds

Textmetadata
LicenceCC BY
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.