Phacoemulsification of the rock-hard dense nuclear cataract: Options and recommendations.

We describe the essential steps in the successful phacoemulsification of the rock-hard, dense cataract. Appropriate and directed preoperative history, physical examination, and diagnostics allow the surgeon to select the best incision, anesthesia, and intended surgical technique for a given dense nuclear challenge. Hard nucleus-specific approaches for hydrodissection, pupil management, and zonular protection then allow the surgeon to approach the rock-hard nucleus with maximum safety. Dense nuclear dismantling options are then discussed in detail along with fluidic and power modulation considerations. Various specific phacoemusification machine settings for rock-hard cataracts from the authors representing several different phaco systems are then presented. The combination of these steps and considerations allow a more successful dense cataract removal and potential restoration of vision for patients. This paper represents the collective experience and advice of the Challenging and Complex Cataract Surgery Subcommittee.

Comparison of corneal power obtained from VERION image-guided surgery system and four other devices.

PURPOSE: To assess the corneal keratometric values obtained using the VERION image-guided surgery system and other devices. METHODS: This study evaluated the right eyes of 115 cataract patients before intraocular lens (IOL) implantation through consecutive tests using 5 devices: VERION Reference Unit, Placido-based corneal topography (OPD-Scan III), monochromatic light-emitting diodes (LenStar LS900 and AL-Scan), and rotary prism technology (auto kerato-refractometer KR-8800). Analyzed parameters were corneal steep and flat keratometric values (Ks and Kf) and corneal astigmatism and axis. These parameters were evaluated using the one-sample two-tailed t-test and the 95% limits of agreement (95% LOAs) between the devices. RESULTS: The mean corneal cylinder value measurements were -0.97±0.63 D, -0.88±0.60 D, -0.90±0.69 D, -0.90±0.67 D, and -0.83±0.60 D with VERION, LenStar, AL-Scan (2.4 mm), OPD III, and KR-8800, respectively. Only KR-8800 showed a significant difference from VERION in the corneal cylinder value (P<0.05). The mean differences in the Kf and Ks of VERION compared to those of OPD III were 0.18±0.45 D and 0.17±0.38 D (P<0.05), respectively. The 95% LOAs of Bland-Altman analysis for the corneal astigmatism axis of the VERION with LenStar, AL-Scan (2.4 mm), OPD III, and KR-8800 were -26.25° to 58.71°, -20.61° to 47.44°, -25.03° to 58.98°, and -27.85° to 65.17°, respectively. CONCLUSION: None of the VERION parameters were significantly different from those of AL-Scan and LenStar. AL-Scan (2.4 mm zone) was especially similar to VERION. Wide LOAs are potential contributors to axis error in patients with toric IOL implants.

Management of the subluxated crystalline lens.

The surgical management of ectopia lentis presents the ophthalmic surgeon with numerous challenges and options. From the clinical evaluation to the surgical approach, ectopia lentis patients require additional methodologies, techniques, and devices to ensure the best possible outcome. The continued refinement of surgical techniques and adjunctive prosthetic devices has led to incremental improvements in the ability to achieve successful in-the-bag placement and centration of intraocular lenses while reducing complications. A thorough understanding of the challenges inherent in ectopia lentis cases and the management of intraoperative complications will ensure that surgeons approaching the correction of these eyes will achieve the best possible surgical results.

Ocular manifestations of dengue fever.

PURPOSE: To evaluate ocular manifestations associated with dengue fever. DESIGN: Retrospective case series and literature review. METHODS: Clinical records of patients with dengue fever who subsequently had ocular symptoms and signs develop were reviewed. The clinical presentation and ocular complications were evaluated. RESULTS: Six patients, 5 females and 1 male, were seen with a sudden decrease in vision 6 to 7 days after the initial manifestations of dengue fever were identified. The diagnosis was confirmed by detection of dengue-specific IgM antibodies (IgM enzyme-linked immunoassay). The presenting best-corrected visual acuity ranged from 20/30 to counting fingers, and ocular involvement was bilateral but asymmetric in 5 cases and unilateral in 1 case. Fundus findings included small, intraretinal, whitish lesions, with localized retinal and retinal pigment epithelium (RPE) disturbance, small dot hemorrhages, and vascular sheathing around the macula and the papillomacular bundle. Fluorescein angiography showed arteriolar focal knobby hyperfluorescence at the macula with mild staining of the vascular walls and leakage at the level of the RPE. All 5 cases that had indocyanine green angiography done showed early diffuse choroidal hyperfluorescence with late silhouetting of the larger choroidal vessels. Five patients received steroid therapy: 1 topical, 2 periocular, and 2 oral. Over 2 to 4 months, RPE discoloration was observed over the affected areas. After the acute episode, 3 patients showed partial recovery of vision, and in the remaining patients, the visual acuity remained stable. CONCLUSIONS: Ocular complications associated with dengue fever are rare but may result in permanent visual impairment.