PIOLs (Phakic intraocular lenses) are an effective treatment option for refractive errors and continue to be a great alternative for individuals who are not ideal candidates for laser vision correction.
Phakic IOLs outperform laser and photorefractive keratectomy in terms of best spectacle-corrected visual acuity (BSCVA), refractive predictability and stability, and patient satisfaction. The complications of corneal ectasia associated with excimer laser surgery and refractive lens exchange (RLE) are eliminated with pIOLs.
However, not all patients are suitable candidates for pIOLs, and careful preoperative screening and selection are crucial to ensure a successful outcome.
Here Spectrum shares some of the key factors to consider when evaluating patients for pIOLs.
PIOLs are most commonly used to correct high myopia, hyperopia, and astigmatism. Patient selection is critical, and the ideal candidate for a phakic intraocular lens is someone who:
- Is over the age of 21 and has stable refractive error for at least one year
- Has no contraindications to surgery, such as severe dry eye or corneal disease
- Has realistic expectations about the outcome of the procedure
- Can comply with postoperative care instructions (attend post-op follow-ups, no rubbing of eyes)
PIOLs are now also available as a solution for the growing demand for Presbyopic correction in the 40+ age group. Ideal candidates are those with high myopia.
The preoperative evaluation is a crucial step in the pIOL selection process. It should include a comprehensive eye examination to assess the patient’s ocular health, visual acuity and, refractive error.
The following tests should be performed:
- Measurement of the refractive error: This includes the measurement of the manifest and cycloplegic refraction. The cycloplegic refraction is essential in cases of Hyperopia and Myopia above -10D.
- Anterior Chamber Depth (ACD): This is critical in determining patient suitability. A minimum Internal Anterior Chamber Depth of 2.8mm is required for all IPCL models, this varies between other PIOLs.
- Anterior segment examination: This includes a thorough examination of the anterior chamber, iris, and lens to identify any abnormalities or contraindications to the procedure.
- White to White measurement (WtW): A minimum of two WtW measurements are required from different devices to ascertain if there are any anomalies in the measurements. WtW is critical in determining the lens size, so detailing the device and model is extremely important as each device measures from slightly different reference points.
- Dilated fundus examination: This is essential to assess the health of the retina, optic nerve, and macula.
- Endothelial cell count: This test measures the number of endothelial cells in the cornea and is critical in determining the risk of endothelial cell loss after surgery. An endothelial cell count <2000 is a contra-indication.
Both careful patient selection and preoperative screening are critical for ensuring the safety and efficacy of PIOLs.
A comprehensive eye examination should be performed to evaluate the patient’s suitability for the procedure. This includes:
- Measurement of the refractive error
- Corneal topography and pachymetry
- Anterior segment examination
- Dilated fundus examination
- Endothelial cell count
The goal is to identify any risk factors that could affect the outcome and to select the most appropriate PIOL for the patient’s needs.
IOL calculation support
Dedicated pIOL calculation support from your provider is essential. Spectrum is part of AddVision, a pan-European network that specialises in ophthalmic products, technologies, and services. Within our network is an experienced calculations team that supports clinics and surgeons across Europe with pIOL calculations.
Drawing on their experience, our calculation specialists review the results together with the data provided. They supply recommendations and appropriate advice to optimise the visual outcomes and reduce the risk of adverse events related to under or oversizing.
At Spectrum, we’re here to support you at every step. To learn more about adding IPCL as a treatment option, backed by excellent calculations and clinical support, please get in touch.