A prospective multicenter clinical trial to evaluate the safety and effectiveness of the implantable miniature telescope.

PURPOSE: To evaluate the safety and preliminary efficacy of a novel visual prosthetic device, the Implantable Miniature Telescope, IMT (by Dr Isaac Lipshitz) (IMT), in a phase I trial in patients with significant bilateral central vision impairment from late-stage age-related macular degeneration (AMD). The IMT is designed to reduce the relative size of the scotoma by rendering enlarged (threefold) central visual field images over the central and peripheral retina. DESIGN: Prospective, multicenter, open-label clinical trial. METHODS: In this prospective, multicenter phase I trial, 14 patients aged 60 or older with bilateral geographic atrophy or disciform scar AMD, cataract, and best-corrected visual acuity (BCVA) between 20/80 and 20/400 had an IMT implanted in one eye. Distance and near BCVA, endothelial cell density, and quality of life, measured as activities of daily life (ADL), were evaluated preoperatively and postoperatively. RESULTS: At 12 months, 10 (77%) of 13 patients gained 2 more lines of either distance or near BCVA, and eight (62%) of 13 patients gained 3 or more lines in either distance or near BCVA. Mean endothelial cell density decreased by 13%. All adverse events resolved without sequelae. ADL scores improved in the majority of patients. CONCLUSION: The results of this phase I trial support further evaluation of the IMT in a larger study population with late-stage AMD. A phase II/III trial is in progress.

Use of power modulations in phacoemulsification. Choo-choo chop and flip phacoemulsification.

We used power modulations in addition to new technology available from 6 phacoemulsification manufacturers and altered our phacoemulsification techniques to take advantage of these technologies to significantly reduce the amount of ultrasound energy placed into the eye and enhance the rapidity and level of visual rehabilitation in patients.

Prevention of posterior segment complications of phacoemulsification.

The prevention of posterior segment complications of cataract surgery depends on the maintenance of an intact lens capsule and zonular apparatus. The phacoemulsification techniques presented here, including cortical cleaving hydrodissection, hydrodelineation, ultrasound power modulation, and management of the epinucleus and cortex, together with the special techniques presented for management of small pupils and compromised zonule, minimize the risk of damage to the posterior capsule by maximizing control of nuclear disassembly and evacuation. Choo-choo chop and flip phacoemulsification, in particular, provides a management strategy for cataracts of all grades of nuclear hardness whether in the presence of a small pupil or compromised zonule.

New techniques and instruments for lens implantation.

Although no major breakthroughs have emerged in the area of lens insertion techniques and technology, small incremental advancements continue to take place for the placement of foldable intraocular lenses through small incisions. Folders have become more innovative in their ability to fold lenses effectively, and inserters have been downsized and enhanced to allow insertion through smaller incisions with more effective purchase of the lens. New cartridge injectors are increasing in popularity because of their ease of use and ability to pass through smaller incisions, especially with modifications. In addition, knowledge regarding techniques and complications of noncapsular supported intraocular lenses continues to increase, adding to our ability to choose the proper technique for secondary lens insertion in these selected patients.

New techniques and instruments for lens implantation.

Although no major breakthroughs have recently emerged in the area of lens insertion techniques and technology, small incremental advancements continue to take place for the placement of foldable intraocular lenses through small incisions. Folders have become more innovative in their ability to effectively fold lenses, and inserters have been downsized and enhanced to allow insertion through smaller incisions with more effective purchase of the lens. New cartridge injectors are increasing in popularity because of their ease of use and ability to pass through smaller incisions, especially with modifications. In addition, increased knowledge regarding techniques and complications of noncapsular supported intraocular lenses continues to be gained, adding to our ability to choose the proper technique for secondary lens insertion in these selected patients.

Late reopening of fibrosed capsular bags to reposition decentered intraocular lenses.

The infrequent postoperative complication of intraocular lens decentration in the presence of an intact fibrosed capsule has traditionally been treated with lens explantation and exchange for a sulcus-fixated lens. Many of these patients can be managed by reopening the fibrosed capsular bag and repositioning the lens within the bag. These cases can be performed quickly using topical anesthesia regardless of the time since the primary cataract procedure.

Transient no light perception visual acuity after intracameral lidocaine injection.

The use of intracameral lidocaine for augmenting analgesia during intraocular surgery is becoming increasingly popular. We report a case of complete visual loss after the use of intracameral lidocaine to repair a traumatic corneal graft dehiscence. Full visual recovery returned several hours after surgery, suggesting this medication's relative lack of retinal toxicity.

Phacoemulsification in the presence of pseudoexfoliation: challenges and options.

Phacoemulsification in the presence of pseudoexfoliation of the lens presents surgeons with particular challenges. The frequency of intraoperative and postoperative complications such as zonular dialysis, capsular tears, vitreous loss, and intraocular lens (IOL) decentration may be reduced with careful attention to detail and careful surgical technique. Improvements in phacoemulsification technology, IOLs, and new capsular supporting rings allow surgeons to perform safer surgery in these eyes. We present the challenges of and options for managing cataract extraction in the presence of pseudoexfoliation.

Phacoemulsification performed in a modified waiting room chair.

Patients unable to fully recline represent challenging cases for the cataract surgeon. Various diseases of the heart, lungs, and spine may prevent certain patients from assuming a supine position, complicating the surgical approach and increasing the risk of intraoperative complications. We altered a common waiting room chair to allow these patients to remain in an upright seated position while their heads maintain the usual supine position commonly obtained with patients positioned on an operating room table.

Refractive aspects of cataract surgery.

The emphasis in cataract surgery has shifted to perfecting the refractive outcome. More accurate lens power calculations and refinement in techniques to reduce or eliminate surgically induced and preexisting astigmatism have moved us closer to the ultimate surgical result-emmetropia. Multifocal lenses and surgically induced multifocal corneas have the potential to eliminate not only myopia and hyperopia but also the loss of accommodation resulting from the pseudophakic state.

New techniques and instruments for lens implantation.

Although most of the new techniques and new instrumentation for intraocular lens implantation are related to foldable intraocular lenses or sutured posterior chamber lenses, there are some intriguing new concepts in intraocular lens techniques unrelated to these two areas.

Pupilloplasty for small pupil phacoemulsification.

In the pupilloplasty technique, the surgeon creates multiple partial sphincterotomies and stretches the sphincterotomies to enlarge any inadequately dilated pupil so that phacoemulsification can be safely performed. The technique recovers excellent physiologic function and cosmesis postoperatively.

Crack and flip phacoemulsification technique.

The crack and flip phacoemulsification technique combines the advantages of circumferential division of the nucleus and nucleofactis techniques. As such, it adds safety and control to the procedure. We describe each of the surgical maneuvers, including machine settings, and explain the rationale for maneuvers and machine settings.

Cortical cleaving hydrodissection.

In this technique, I/A of cortex as a separate step can be omitted, thereby eliminating that portion of the surgical procedure in which posterior capsular disruption most frequently occurs. Residual cortical cleanup is accomplished in the presence of a posterior chamber IOL which protects the poserior capsule by holding it remote from the aspiration port.