Mark Mulhern

Endophthalmitis after astigmatic myopic laser in situ keratomileusis

Abstract A 36‐year‐old woman had uneventful astigmatic myopic laser in situ keratomileusis (LASIK) to correct −12.00 −1.50 × 70. Three days later, she developed a corneal abscess, hypopyon, and an intense vitreous cellular reaction—endophthalmitis. The patient was immediately given intravenous ciprofloxacin and topical vancomycin and ceftazidime. The infecting organism was Streptococcus pneumoniae. One day after therapy was instituted, the hypopyon resolved. Seven months later, best corrected visual acuity was 20/25 and refractive error, −4.00 diopters. A stromal scar (grade 2 haze) was causing a slight reduction in acuity. Endophthalmitis after LASIK, if treated promptly, need not lead to a permanent reduction in visual acuity.

Topographical analysis of ablation centration after excimer laser photorefractive keratectomy and laser in situ keratomileusis for high myopia

Purpose: To evaluate the ablation centration after photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) for high myopia and to assess the association between decentration and best corrected visual acuity (BCVA), glare, monocular diplopia, and halo phenomenon. Setting: Mater Private Hospital, Dublin, Ireland. Methods: Corneal topography was used to analyze centration in two groups of patients with myopia of more than 6.0 diopters: 18 had PRK and 18, LASIK. A standardized questionnaire assessed the preoperative and postoperative prevalence of glare, monocular diplopia, and halo phenomenon. Results: “Significant” ablation decentration (0.5 mm) in the LASIK group (1.33 mm) was almost twice that in the PRK group (0.75 mm). Glare increased from 27% preoperatively to 42% in the PRK group; monocular diplopia increased in the LASIK group. Halo phenomenon decreased after both procedures. Conclusion: Laser in situ keratomileusis represents a step forward in the surgical correction of high myopia, but the accuracy of the corneal ablation location must be improved. Suction ring fixation of the globe or real time tracking systems may help improve centration.

Myopic and hyperopic laser in situ keratomileusis retreatments : Indications, techniques, limitations, and results

Purpose: To assess the efficacy of myopic and hyperopic laser in situ keratomileusis (LASIK) retreatment procedures. Setting: Mater Private Hospital, Dublin, Ireland. Methods: Retreatment was defined as either lifting the previously created flap or when this was not possible, cutting a new flap. Fifty‐six patients were retreated, 17 with hyperopia (Group 1) and 39 with myopia (Group 2). The mean preoperative spherical equivalent in Group 1 was +3.79 diopters (D) ± 1.53 (SD) (range +1.75 to +8.12 D) and in Group 2, −5.46 ± 2.87 D (range −0.38 to −15.25 D). Results: The indications for retreatment were undercorrection, decentration, epithelial ingrowth, and central island. Postoperatively, the mean spherical equivalents in Groups 1 and 2 were +1.11 ± 2.02 D (range −1.75 to +5.50 D) and −1.02 ± 2.20 D (range +4.75 to −9.00 D), respectively. In Group 1, the uncorrected visual acuity (UCVA) was 6/12 or better in 5.8% preoperatively and in 35% postoperatively. In Group 2, the UCVA was 6/12 or better in 5.1% preoperatively and in 59.0% postoperatively. Although 29% of the hyperopic eyes and 8% of the myopic eyes lost 1 Snellen line of best corrected visual acuity (BCVA), there was an improvement (of 1 or more lines) in BCVA in 12% and 49%, respectively. In cases that were decentered preoperatively, the postoperative optical zone ablation centration was better in 85.7% of Group 1 eyes and 61.5% of Group 2 eyes. Corneal complications following retreatment included peripheral scarring, epithelial ingrowth, Bowmans folds, and keratectasia. Conclusions: Both myopic and hyperopic retreatments resulted in a stable refractive outcome. Myopic retreatments were superior to hyperopic retreatments in both efficacy and safety.

Reproducibility of LASIK flap thickness using the Hansatome microkeratome.

Purpose: To evaluate the actual versus the expected thickness of laser in situ keratomileusis (LASIK) flaps and to determine the factors that affect flap thickness. Setting: Centre For Sight, Queen Victoria Hospital, East Grinstead, United Kingdom. Methods: A retrospective analysis of LASIK procedures in 757 consecutive eyes was done. The surgery was performed by a single surgeon using 2 Hansatome® microkeratomes (Bausch & Lomb) with 160 &mgr;m and 180 &mgr;m heads. Patient age, preoperative manifest refraction, automated keratometry, preoperative central pachymetry, and intraoperative stromal pachymetry were evaluated to determine whether they influenced the actual flap thickness. Results: Bilateral LASIK was performed in 343 patients (686 eyes). The 160 &mgr;m head was used in 641 eyes (84.6%) (Group 1) and the 180 &mgr;m head, in 116 eyes (15.4%) (Group 2). The mean preoperative manifest refraction spherical equivalent (SE) was −3.9 diopters (D) ± 4.5 (SD) (range +7.4 to −25.0 D) in Group 1 and −4.4 ± 3.7 D (range +7.1 to −12.9 D) in Group 2. The mean preoperative keratometry reading was 43.6 ± 1.8 D (range 36.0 to 48.6 D) and 43.6 ± 1.8 D (range 35.9 to 47.0 D), respectively; the mean preoperative central pachymetry was 543 ± 35 &mgr;m (range 447 to 643 &mgr;m) and 548 ± 31 &mgr;m (range 453 to 613 &mgr;m), respectively; and the mean flap thickness was 116.4 ± 19.8 &mgr;m and 117.3 ± 18.0 &mgr;m, respectively. The difference between the actual and the expected flap thickness in each group was statistically significant (P<.001). There was no significant difference in the actual flap thickness between the 2 Hansatomes. The preoperative SE and central pachymetry were the only factors that influenced the actual flap thickness (P<.05); thin flaps were more common with increasing myopia and increasing corneal thickness. Conclusions: Spherical equivalent and preoperative pachymetry were the principal factors that influenced flap thickness. Preoperative keratometry values and patient age did not influence the actual flap thickness.

Synchronous Reconstruction of the Exenterated Orbit with a Pericranial Flap, Skin Graft and Osseointegrated Implants

Reconstruction of the exenterated orbit remains a surgical challenge. Here, the authors present a case in which orbital exenteration was performed for an extensive, infiltrating medial canthal basal cell carcinoma; the resulting defect was reconstructed with osseointegrated implants and a pericranial flap onto which a split thickness skin graft was placed. The second stage of the aesthetic rehabilitation of this patient (placement of the transcutaneous abutments) was completed under local anaesthetic 16 weeks later. Subsequently, the patient was fitted with an oculoplastic prosthesis four weeks later. The above technique accelerates the prosthetic rehabilitation of the patient by performing the primary reconstructive procedures simultaneously with the exenteration and by removing the need for secondary surgical procedures under general anaesthetics. The whole process from orbital exenteration to the fitting of an ocular prosthesis was completed in just five months.

A non-invasive pigmented nodule arising within primary acquired melanosis--an unusual phenomenon.

We report a case of a raised pigmented nodule that arose within conjunctival primary acquired melanosis (PAM). This nodule showed no histological features of invasive disease.

The E-Z(easy) clamp--a new instrument to facilitate medial ectropion repair.

The medial spindle/retropunctal diamond procedure is a useful technique to correct medial ectropion. Unfortunately, the procedure is difficult, due to the limited size of the surgical field, the bleeding that is seen when the marginal artery is encountered and because of the ever present risk of damaging the canaliculus. We have developed a clamp that overcomes the anatomical opposition outlined above and at the same time improves access to the surgical field.