Multicenter Study on the Use of Intraoperative OCT in the Diagnosis and Management of Lens Diseases

Lens disorders, particularly cataract, are a leading cause of blindness worldwide and substantially impair quality of life. Surgery remains the most effective treatment, but pre-existing abnormalities of the lens and adjacent ocular structures, together with unexpected intraoperative events, may increase surgical complexity and affect outcomes. Accurate assessment of anterior segment structures is therefore essential, as abnormalities caused by trauma, congenital disorders, ocular diseases, or systemic conditions may involve the lens, capsule, cornea, iris, or anterior chamber angle. Even during routine phacoemulsification, variations in irrigation pressure, anterior chamber depth, capsular bag integrity, capsular expansion, and residual cortex may influence surgical safety, IOL centration, and postoperative refractive stability. Because some abnormalities cannot be reliably detected preoperatively, intraoperative optical coherence tomography (iOCT) may provide real-time structural information and support surgical decision-making. However, evidence regarding its effects on surgical strategy, visual outcomes, refractive stability, and complications remains limited. This multicenter retrospective study will assess the associations between preoperative and intraoperative anterior segment changes and postoperative outcomes, and evaluate the clinical value of iOCT in lens surgery.

• Intraoperative Optical Coherence Tomography (Device): Intraoperative optical coherence tomography technique can provide intraocular images and show changes in intraocular structures, assisting in analyzing the correlation between preoperative, intraoperative anterior segment structural changes and postoperative surgical effects in patients with lens diseases.

Primary outcomes

• Concordance Rate Between Preoperative and Intraoperative Diagnoses [From completion of the preoperative examinations through the end of surgery; diagnostic concordance is assessed after surgery.]: Preoperative diagnoses are determined based on routine ophthalmic examinations. Intraoperative diagnoses are determined based on surgical microscopic observations, intraoperative OCT images, and operative records. Concordance between the preoperative and intraoperative diagnoses is assessed, including whether the intraoperative diagnosis adds to or corrects the preoperative diagnosis.

Secondary outcomes

• Intraocular Lens Tilt Angle [After intraocular lens implantation and at the end of surgery.]: The tilt angle of the implanted intraocular lens is measured on intraoperative OCT images using a standardized image analysis protocol. A predefined ocular-axis reference line is used to calculate the angle between the intraocular lens axis and the reference axis.
• Incidence of Intraoperative Complications [From the start to the end of surgery.]: Intraoperative complications are identified from operative records and intraoperative imaging. The incidence of each complication is calculated.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Aged 18 years or older.
* Presence of lens opacity or abnormal lens position.
* Visual impairment affecting activities of daily living.
* Met the indications for lens surgery.
* Underwent lens surgery.

Exclusion Criteria:

* Active intraocular inflammation.
* Uncontrolled systemic disease, use of medications that could significantly affect surgery, or other standard contraindications to lens surgery.
* Incomplete or unreliable key preoperative examination data, including ocular biometry.
* Inadequate image quality due to poor fixation or other causes, rendering the images unsuitable for analysis.
* Incomplete intraoperative OCT recordings, such as interrupted recording or severe image freezing, affecting data evaluation.
* Other psychological or physical conditions that might interfere with study participation.