Analyse vectorielle de la correction de l’astigmatisme par incisions arciformes au laser femtoseconde dans les astigmatismes géants post-kératoplastie transfixiante

Astigmatism research and application of vector method of the last half century: a bibliometric and visualized analysis

Background

As a common type of refractive error, astigmatism has always been one of the important factors affecting visual quality in clinical practice and it is quite an important public health burden. This study aims to evaluate astigmatism research and the clinical application of the vector method of the past half-century through a broad scientometric analysis, and to explore its reference value for guiding clinical treatment.

Methods

The literature search was conducted on the Web of Science for astigmatic vector studies published from 1965 to August 2024. Retrieved publications were analyzed by the number of annual publications, prolific countries, and researchers, core publications and journals, and the number of citations through descriptive statistics. Collaboration networks and keyword analysis were visualized by VOSviewer and CiteSpace.

Results

One thousand and fifty-nine publications were included for a visualized analysis. Vector methods help researchers to describe astigmatism specialized, and clinicians are mainly focused on the correction of astigmatism in both corneal and cataract surgery. Journal of Cataract and Refractive Surgery was the core journal for this field. The United States accounts for the largest proportion of publications and Australia had the highest citation ratio. Through the keyword analysis, the network identified 4 major research trends of corneal refractive surgery, penetrating keratoplasty, cataract surgery, and epidemiological surveys of astigmatism. "Photorefractive keratectomy," "postoperative astigmatism" and "surgery" had significant burst strength and continuous attention to the astigmatism vector analysis.

Conclusion

Vector analysis is the most commonly used method to evaluate astigmatism and could significantly improve the accuracy of astigmatism correction, particularly in areas of refractive and cataract surgery. The application of vector analysis is beneficial in guiding the design of surgical incisions, determining the nomogram, optimizing the surgical protocol, and improving the accuracy of astigmatism correction. Meanwhile, the popularization of vector method will help to improve the accuracy of astigmatism analysis and promote the benign development of public health.

Repeated Femtosecond Laser-Assisted Astigmatic Keratotomies in Post-Keratoplasty Eyes

Visual rehabilitation after a keratoplasty is often compromised due to high amounts of residual astigmatism. Femtosecond laser-assisted astigmatic keratotomy (FLAK) is gaining popularity in decreasing this astigmatism. Though one set of two incisions suffices in most cases, sometimes the treatment proves insufficient and additional treatment is required. This case series evaluates the outcomes in patients who underwent two consecutive FLAK sets to correct post-keratoplasty residual astigmatism. All repeated FLAK cases performed on post-keratoplasty eyes were reviewed in a high-volume clinic as a non-comparative retrospective case series. The data extracted include the procedure parameters, time between procedures, refraction including sphere, astigmatism, spherical equivalent (SE), and uncorrected and best-spectacle-corrected distance visual acuity (UDVA, BSDVA, respectively). Eleven eyes of eleven patients aged 25.5 ± 10 treated with more than one FLAK procedure were identified. The average follow-up time was 6 months after the first FLAK and 24 ± 10 months after the second. The second FLAK was performed six months after the first. The preoperative mean astigmatism was −9.59 ± 2.36 D. At the final follow-up, the mean astigmatism decreased to −5.38 ± 1.79 D (p = 0.001). Repeated FLAK procedures achieved a significant and stable reduction of astigmatism in post-keratoplasty eyes. This procedure shows safety and effectivity in these complex eyes and may prevent the need for a further keratoplasty.