PVD after phaco affects quality of vision, reading speed

Take-Home

Findings evaluating the incidence of posterior vitreous detachment on quality of vision and reading speed have been released.

By Lynda Charters; Reviewed by Nicola Hauranieh, MD

Brescia, Italy-An increase in the incidence of posterior vitreous detachment (PVD) after cataract surgery may directly impact postoperative quality of vision by affecting the patient’s reading speed.

In a study of the quality of vision in this scenario, reading speed varied depending on whether the PVD was symptomatic or asymptomatic, said Nicola Hauranieh, MD.

The study aimed to evaluate the incidence of PVD after phacoemulsification using optical coherence tomography (OCT) and to determine if it causes less quality of vision, especially reading speed.

“Using OCT, our study found an increase in the incidence of PVD after cataract surgery,” Dr. Hauranieh said. “Only 20% of the eyes in which PVD developed were symptomatic. Patients with symptomatic PVD had impaired quality of vision that was reflected in the reading speed compared with patients with asymptomatic PVD and those with no PVD.”

Patient satisfaction with the results of cataract surgery is related to the preoperative expectations and the quality of vision resulting from the surgery. The quality of vision is impacted by the resultant visual acuity and the ability to read at all distances.

Numerous factors are involved in the quality of vision, including:

·      The quality of IOLs-i.e., the use of premium, toric, multifocal, accommodative, and aspheric lenses and IOLs with low rates of development of posterior capsular opacification (PCO).

·      The quality of the cataract surgery itself-i.e., induced astigmatism, creation of a perfect capsulorhexis, achievement of emmetropia, low PCO rates, and a low rate of PVD.

To investigate the effect of PVD on the quality of vision and reading speed, Dr. Hauranieh, Pietro Giardini, MD, and Piero Giardini, MD, from Polivisus, Brescia, Italy, conducted a study in which they evaluated the incidence of PVD after phacoemulsification using optical coherence tomography (OCT) and determined if the resultant quality of vision was lower with a focus on reduced reading speed.

The length of the cataract surgery, the amount of balanced saline solution used, and the height of the bottle are factors that may help induce PVD, Dr. Hauranieh noted.

However, only four recent studies in the literature have addressed the incidence of PVD following phacoemulsification.

The experience of Dr. Hauranieh and colleagues included 50 patients with no PVD visualized on OCT. Patients underwent uneventful cataract surgery in which a 2.2-mm incision was created, a foldable IOL was implanted, and the bottle height was 100 cm.

Preoperative best-corrected distance and near visual acuities were 0.41 and 0.8 logarithm of the minimum angle of resolution, and the preoperative reading speed was 72 words per minute. Postoperatively, the respective values were 0.86, 0.3, and 114 words per minute.

Twenty-nine eyes (58%) developed asymptomatic PVD 1 month after surgery, and by 3 months postoperatively 35 eyes (70%) developed asymptomatic PVD, Dr. Hauranieh noted.

“However, only 10 (20%) of the study eyes had symptomatic PVD,” he said.

The investigators measured patients’ reading speed preoperatively and postoperatively on days 7, 30, and 90 using a near and intermediate visual performance analyzing system (Eyevispod) on a high-definition tablet/device. Patients also underwent OCT.

Symptomatic PVD, reading speed

The investigators found that in 15 eyes in which no PVD developed after cataract surgery, the patients read a mean of 120 words per minute. In the 25 eyes with asymptomatic PVD, the mean reading speed decreased to about 114 words per minute. In the 10 eyes with symptomatic PVD, the reading speed was about 107 words per minute.

“The reading speed was often characterized by several disturbing interruptions and hesitations due to the fluctuation of the detached posterior vitreous,” Dr. Hauranieh said.

Nicola Hauranieh, MD

E: nicola@hauranieh.com

This article was adapted from Dr. Hauranieh’s presentation at the 2014 meeting of the American Society of Cataract and Refractive Surgery. Dr. Hauranieh has no financial interest in the subject matter.