R. Fasciani

Role of the corneal epithelium in refractive changes following laser in situ keratomileusis for high myopia.

PURPOSE Epithelial hyperplasia is one of the factors that plays a role in myopic regression after photorefractive keratectomy (PRK). We evaluated the role of the epithelium following excimer laser in situ keratomileusis (LASIK) performed on highly myopic eyes. METHODS Fifty eyes of 32 patients (18 females and 14 males; mean age, 31.7+/-6.5 years) were treated with LASIK for myopia with an attempted correction ranging between -8.50 and -12.25 D (mean, -10.48+/-1.43 D). No sutures were placed. The thickness of the central epithelium was evaluated either with a 50-MHz ultrasonic pachymeter or an ultrasound biomicroscope. Postoperatively, topical corticosteroid drops were administered for at least 1 month. RESULTS Follow-up was at least 12 months. Epithelium measurements were thicker compared to preoperative measurements from the first week postoperatively (mean, +1.9 microm, +2.77%; P<.05). Epithelial thickness peaked at the third month after LASIK (mean, +6.5 microm, +9.5%; P<.05) and remained stable through 12 months. A negative correlation between epithelium thickness and manifest refraction from the first month postoperatively to the end of follow-up was present. CONCLUSION The epithelium seemed to have a role in the regression of refractive effect after LASIK to correct high myopia.

Biological parameters determining the clinical outcome of autologous cultures of limbal stem cells

AIM Limbal cultures restore the corneal epithelium in patients with ocular burns. We investigated the biological parameters instrumental for their clinical success. METHODS We report a long-term multicenter prospective study on 152 patients carrying corneal destruction due to severe ocular burns, treated with autologous limbal cells cultured on fibrin and clinical-grade 3T3-J2 feeder cells. Clinical results were statistically evaluated both by parametric and nonparametric methods. RESULTS Clinical outcomes were scored as full success, partial success and failure in 66.05, 19.14 and 14.81% of eyes, respectively. The total number of clonogenic cells, colony size, growth rate and presence of conjunctival cells could not predict clinical results. Instead, the clinical data provided conclusive evidence that graft quality and likelihood of a successful outcome rely on an accurate evaluation of the number of stem cells detected before transplantation as holoclones expressing high levels of the p63 transcription factor. No adverse effects related to the feeder layer have been observed and the regenerated epithelium was completely devoid of any 3T3-J2 contamination. CONCLUSION Cultures of limbal stem cells can be safely used to successfully treat massive destruction of the human cornea. We emphasize the importance of a discipline for defining the suitability and the quality of cultured epithelial grafts, which are relevant to the future clinical use of any cultured cell type.

Latrogenic keratectasia following laser in situ keratomileusis.

PURPOSE To evaluate keratectasia after laser in situ keratomileusis (LASIK) for high myopia. METHODS A 49-year-old male patient with myopia of -23.50 D in both eyes underwent LASIK with a Summit Technology Apex Plus excimer laser. A Moria manually-guided MDSC microkeratome was used. Preoperative corneal topography in both eyes did not reveal underlying or fruste form of keratoconus. Four months after LASIK, a progressive keratectasia occurred in right eye and after 12 months, in left eye. Corneal transplantation was performed in both eyes. RESULTS Histological and ultrastructural examinations were performed on one corneal button. The analysis showed regular stromal morphology and cellularity, with no sign of inflammation. The morphometric analysis showed an overall thickness of 334 microm, with a flap of 262 microm and a stromal residual bed of 72 microm, in the center of the button. CONCLUSION A LASIK corneal flap made with a planned 120-microm plate turned out histologically to be approximately 260 microm thick, in an eye with a refractive correction of -23.50 D. The excessive flap thickness and excessive ablation produced progressive keratectasia requiring a penetrating keratoplasty.

Ocular Mucous Membrane Pemphigoid after Lyell Syndrome: Occasional Finding or Predisposing Event?

PURPOSE Ocular mucous membrane pemphigoid (OMMP) is an autoimmune disease involving the eye and characterized by subepithelial detachment resulting from an immunologic reaction against conjunctival basal membrane zone (BMZ) antigens. Lyell syndrome (LS) is a drug-induced, T cell-mediated, cytotoxic reaction involving the mucocutaneous areas. Two patients with LS are presented in whom OMMP developed. DESIGN Report of 2 cases. PARTICIPANTS Two male patients, 80 and 60 years old, with persistent corneal ulcerations, corneal melting, and inflammation some months after an LS episode. METHODS Conjunctival biopsy samples were obtained to perform direct immunofluorescence (DIF) and histologic analyses. Indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assay (ELISA) also were performed. MAIN OUTCOME MEASURES Immunodeposit findings on the conjunctival BMZ obtained by DIF and IIF, inflammatory infiltration of the corneoconjunctival samples studied by histologic analysis, and autoantibodies of patient sera directed against BMZ antigens tested by ELISA. RESULTS Direct immunofluorescence analyses showed immunoglobulin G and complement 3 component deposits along the BMZ in a linear pattern. Histologic analysis revealed the presence of eosinophils, neutrophils, and mast cells with fibrin deposition in the substantia propria of both patients; the data confirmed the clinical suspicion of OMMP. The IIF and ELISA results were negative. CONCLUSIONS Chronic eye surface injury associated with LS may promote autoimmunization against ocular epithelial BMZ antigens, playing a strategic role in the subsequent onset of OMMP. The occurrence of OMMP after LS could be an occasional finding, or conversely, LS could be an underestimated predisposing factor in the development of OMMP.

Graft rejection after femtosecond laser-assisted deep anterior lamellar keratoplasty: report of 3 cases.

Purpose: To report 3 cases of stromal rejection after deep anterior lamellar keratoplasty (DALK) assisted by a femtosecond laser. Methods: Three keratoconus eyes of 2 men (22 and 30 years old) and 1 woman (24 years old) who had DALK with a 60-kHz femtosecond laser developed intrastromal graft rejection with superficial and deep neovascularization after 6, 15, and 12 months, respectively. All patients underwent confocal microscopy and were treated with topical steroid therapy. Results: In vivo confocal microscopy revealed cellular inflammatory infiltrates in the subepithelial and middle stroma of the donor lamella without involvement of the endothelium. Graft rejection was rapidly reversed with topical steroid therapy, and a clear cornea was restored in all cases. Conclusions: Graft rejection remains a significant complication of lamellar surgery but is associated with good tissue restoration and complete visual recovery.

Femtosecond Laser Assisted Lamellar Keratoplasties

The concept of lamellar keratoplasty (LK) is that of targeted lamellar replacement of corneal tissue while retaining normal cornea. It involves replacing anterior stroma at different deepness with an anterior lamellar keratoplasty (ALK). Despite the significant advantages of LK surgery, penetrating keratoplasty (PK) remains the most common procedure, largely because lamellar surgery is more technically demanding and time consuming 1. Moreover, interface irregularity arising from manual lamellar dissection often results in suboptimal visual outcomes 2. Long-term graft survival rates and endothelial cell counts after PK continue to drop for many years after surgery, clearly showing the disadvantage of unnecessary replacement of a healthy endothelium in anterior-stromal disorders 3. For these reasons, PK is now being replaced by various types of lamellar techniques that aim to replace damaged tissue only, while maintaining healthy tissue intact. Recent improvements of surgical techniques and advances in instrumentation, such as microkeratome-assisted LK (ALTK) 4, and excimer laser assisted LK (ELLK), 5,6 have contributed to improve visual quality in corneal lamellar surgery, promoting a paradigm shift in the surgical treatment of anterior corneal disease. The new femtosecond laser technology has been introduced for ophthalmic surgery in the last years with the aim to resolve the microkeratomes related problems in LASIK surgery 7. This new technology has been shown to be the “top” to perform LASIK flaps, creating flaps of precise and homogeneous thickness, reducing the flap related problems (free cap, button hole, flap irregularity) and leaving more stroma for the excimer ablation allowing to correct higher refractive defects (especially with the ultrathin flaps of 90 microns). Moreover, the femtolaser technology, allowing to perform precise corneal cuts with a planned and customized shape, offers clear advantages also applied in anterior lamellar keratoplasty (ALK) surgery8-10. Penetrating Keratoplasty (PK) is still the most common and effective technique for corneal transplantation, but is an “open sky” surgical technique and could be complicated by choroidal effusion or haemorrage, spontaneous lens expression and vitreous loss 1. Moreover, this technique is characterized by an everlasting endothelial cell loss, leading to corneal decompensation necessitating a re-PK to restore a clear graft. To avoid these risks, more conservative surgical techniques have been proposed for the treatment of anterior corneal pathologies with healthy endothelium, enclosed in the great chapter of the lamellar keratoplasty (LK) 2, 3. So that, during the last 10 years, to increase the results of traditional

Unusual coexistence of bilateral keratoconus and optic disc pit: a case report.

Purpose To report the unknown coexistence of bilateral optic disc pit and keratoconus. Methods A 23-year-old man with bilateral keratoconus underwent complete ophthalmology screening, with an unexpected detection of undiagnosed optic disc pit in both eyes. Computerized corneal topography (CT), Orbscan, corneal pachometry, endothelial microscopy, and optical coherence tomography (OCT) examination were performed. Results The corneal CT showed a keratoconus pattern in both eyes, evolved in the right eye with a minimum corneal pachometry of 336 μm in the right eye and 405 μm in the left eye. Mean endothelial cell density was 1937 cells/mm2 in the right eye and 1912 cells/mm2 in the left eye. The OCT scans showed the presence of the disc pit in both eyes with a normal macular thickness and profile in the right eye, and in the left eye an augmented retinal thickness in the nasal macular zone due to retinal oedema and schisis, with an initial detachment of the neuroepithelium in the parapapillary area starting from the optic pit. Conclusions This is the first clinical report of bilateral optic disc pit and keratoconus. Further investigations will be necessary to assess if there is a possible pathogenetic correlation between these two ocular pathologies or if this is an unusual coexistence of separate entities.

Influence of aqueous humor convection current on IOL opacification

Background and PurposeThe opacification of Akreos Adapt (Bausch & Lomb, Rochester; NY) intraocular lens (IOL) has been previously reported in Literature. A metabolic change in aqueous humour was considered as the main trigger factor to IOL opacification. We report our case and discuss the association with Ex-PRESS, highlighting the particular pattern of IOL opacification and its possible relation with the intraocular convective motions of the aqueous.Material and MethodsWe analyzed our case using both digital slit lamp acquisition and OCT Visante (Zeiss, Germany) images. A literature review was conducted to evaluate our results with that previously reported.ConclusionThe role of a relative stationary flow was reported as suggested concurrent mechanism in IOL opacification phenomenon.

Surgical treatment of total bilateral ankyloblepharon in a child: unusual case report

Purpose To report on the efficacy of surgical management of total bilateral ankyloblepharon in a child. Methods An 8-year-old African girl from Burundi presented with complete lid-corneo-conjunctival adhesion in both eyes, dating back 6 years. Preoperative ultrasound evaluation of anterior and posterior segment was detected. Electrophysiologic examinations showed low responses. Surgery was performed with scarring tissue removal through manual cleavage in order to separate tarsal conjunctiva and corneal stroma, followed by multiple human amniotic membrane grafts on the cornea, the entire bulbar surface, and fornices. Results Ankyloblepharon removal, excellent width of fornices, and lid motility recovery were obtained. Nevertheless, corneal stroma remained cloudy. The patients visual acuity reached hand movements perception at 6 months follow-up. Conclusions Even in the presence of deep deprivation amblyopia, total ankyloblepharon surgical removal and anatomic restoration of ocular surface is mandatory in children. Subsequent surgery including corneal keratoplasty or keratoprosthesis implant should be taken into consideration after an accurate evaluation of the cost/benefit ratio. Furthermore, these young patients could be enrolled in specific visual rehabilitation programs to enhance residual visual abilities.