Combined 20-gauge and 23-gauge pars plana vitrectomy for the management of posteriorly dislocated lens: a case series

Scleral patch grafting for scleral wound thinning after pars plana phacoemulsification and aspiration: A case report

RATIONALE

Here we report the case of a patient who required closure with an autologous scleral patch graft during reoperation after developing marked scleral thinning in the late stage after pars plana phacoemulsification and aspiration (PPPEA). To the best of our knowledge, this is the first reports of the procedure being used for the treatment of a thinned scleral section post PPPEA.

PATIENT CONCERNS

This study involved a 73-year-old woman who had undergone vitreous surgery combined with PPPEA for retinal detachment in her right eye 8 years earlier and subsequently underwent intraocular lens (IOL) ciliary sulcus suture fixation.

DIAGNOSES

She became aware of visual disturbance in her right eye and slit-lamp examination revealed the dislocation of the IOL.

INTERVENTIONS

To remove the dislocated IOL and resuture the nasal loop back onto the ciliary sulcus of the patient's right eye, a 25-guage trocar was placed on the superior temporal side.

OUTCOMES

Subsequent removal of the trocar from the patient's right eye left an approximately 3-mm-wide oval-shaped gap at the trocar insertion site due to extreme thinning of the sclera in that area; that is, the location where the PPPEA was performed. Since suture fixation failed to stop intraocular fluid leakage, an inferior free half-thickness scleral flap was created to patch the scleral wound. Postsurgery, the leakage in that eye stopped and the intraocular pressure was stable. No complications were observed during the 1-year-postoperative follow-up period.

LESSONS

Since thermal injuries during PPPEA may lead to postoperative scleral thinning, surgeons should avoid the site of a prior PPPEA when constructing a scleral wound during reoperation.

Investigation of scleral thermal injuries caused by ultrasonic pars plana phacoemulsification and aspiration using pig eyes

PURPOSE

The purpose of this study was to investigate the thermal injuries caused by ultrasonic pars plana phacoemulsification and aspiration (PPPEA) using pig eyes.

METHOD

Using a 20-gauge (G) vitrectomy system (Accurus^®, Fragmatome; Alcon Laboratories) in both the 'open-tip' and 'closed-tip' techniques, PPPEA was performed in pig eyes and the subsequent thermal injuries generated around the scleral wound were measured by infrared thermal imaging (thermography). Post surgery, the state of the scleral wound was observed under a microscope, and a tissue slice containing the scleral wound was then prepared and observed under an optical microscope.

RESULTS

Thermography measurements revealed a slight temperature rise around the scleral wound in the open-tip case, yet a marked temperature rise in the closed-tip case. The scleral wound incision produced by the open tip was linear, while that produced by the closed tip was expanded. Histological examination revealed mild degeneration of the sclera around the wound in the open-tip case, yet marked tissue degeneration by thermal injuries in the closed-tip case.

CONCLUSION

Our findings showed that in PPPEA, the temperature of the tip of a 20G vitrectomy system rapidly increases due to the closed-tip technique, thus producing obvious thermal damage to the scleral wound. In order to prevent thermal injuries to the scleral wound during PPPEA, it is important to shorten the time of ultrasonic oscillation during surgery as much as possible while the tip is occluded with nuclear fragments.

23-gauge vitrectomy for retained lens material

A technique for removal of retained lens material is described with a three-port 23-gauge vitrectomy system. Removal of the core vitreous is first performed, followed by removal of the cortical vitreous. All vitreous adhesions to the lens are cleared. The cut rate is then decreased to 1,500 cuts per minute, and vacuum increased to 600 mm Hg. The cortical lens material is cleared first, and then the nuclear material is taken with the same vitrectomy probe using the light pipe to assist in crushing the nuclear fragments. With this technique, even large dense nuclear and cortical retained lens material can be removed from the vitreous chamber without the need for a fragmatome.

23-gauge pars plana vitrectomy for management of posteriorly dislocated crystalline lens

Purpose

Management of posteriorly dislocated crystalline lens has traditionally been performed with a standard 20-gauge vitrectomy system. This study demonstrates the use of a 23-gauge vitrectomy system for removal of retained lens fragments secondary to spontaneous dislocation or complicated cataract extraction.

Methods

A retrospective, noncomparative, interventional consecutive case series at a single university medical center.

Results

Fourteen eyes of 14 patients underwent a 23-gauge vitrectomy for removal of retained lens. Mean age was 75 years. Mean logMAR (logarithm of minimum angle of resolution) visual acuity was 1.47 (Snellen equivalent 20/600) preoperatively and 0.37 (Snellen equivalent 20/50) postoperatively. A 20-gauge fragmatome was used in 64% of cases. The mean time to the best post-vitrectomy acuity was 4.9 weeks. The mean healing time was 25 days (6–48 days). Post- vitrectomy complications included choroidal detachment (two patients), vitreous hemorrhage (two patients), and acute ocular hypertension (two patients). The mean length of follow-up was 6.2 months (1–13 months).

Conclusion

A 23-gauge vitrectomy system alone or in combination with the 20-gauge fragmatome is a safe and efficacious option for removal of dense posteriorly dislocated crystalline lens material.