Paul Dighiero

Confocal microscopy in Bowman and stromal corneal dystrophies.

OBJECTIVE To use confocal microscopy to demonstrate the similarity among three autosomal-dominant corneal dystrophies and the diversity of the deposit patterns within a single dystrophy. DESIGN A prospective, comparative case series. PARTICIPANTS Twenty patients (40 eyes) from 10 families suffering from Bowman or stromal dystrophy agreed to take part: 3 with Reis-Bückler dystrophy, 12 with granular dystrophy, and 5 with lattice type-I dystrophy. Of these, nine had recurrence in their grafts or after phototherapeutic keratectomy before the confocal examination. The confocal images of affected corneas were compared with those of ten normal control eyes (ten subjects). INTERVENTION All patients were examined by slit-lamp biomicroscopy. Confocal microscopy was performed with Achroplan 40x/numeric aperture (NA) = 0.75 and 63x/NA = 0.9 water immersion objectives. Image analysis was used to identify the corneal epithelial and stromal deposits correlated with each disorder. MAIN OUTCOMES MEASURES Selected images of the corneal layers were evaluated qualitatively for the size, shape, light scattering, and reflection of the deposits. RESULTS Slit-lamp biomicroscopy showed stromal involvement in all affected eyes. Confocal microscopy identified epithelial deposits in 30% of the eyes and stromal deposits in all eyes. The deposits within the epithelium were revealed more clearly with the 63x/NA = 0.9 objective (higher numeric aperture). Some of the confocal findings near the Bowman layer were common for all three dystrophies. Normal control eyes showed no epithelial or stromal deposits, either by biomicroscopy or confocal microscopy. CONCLUSIONS Confocal microscopy provides an in vivo evaluation of the deposits in the cornea, with a higher resolution than biomicroscopy. The confocal findings common to the three dystrophies may agree with previous hypotheses of the same genetic origin. It may be a useful adjunct to slit-lamp biomicroscopy, particularly when histopathologic studies cannot be performed.

A new mutation (A546T) of the βig-h3 gene responsible for a French lattice corneal dystrophy type IIIA

PURPOSE To characterize the betaig-h3 gene defect in a French family affected with lattice corneal dystrophy type IIIA (LCDIIIA). METHODS Histologic examination was performed from corneal buttons of two patients. Genomic DNA was extracted from leukocytes, and exons of the betaig-h3 gene were amplified by polymerase chain reaction to be directly sequenced. RESULTS Numerous deposits were evident in the stroma and beneath the Bowman membrane, which had all the features of amyloid deposits. Analysis of exon 12 revealed a heterozygous G to A transition on codon 546. CONCLUSION In contrast to Japanese patients, these French patients affected with LCDIIIA carry a distinct mutation of the betaig-h3 gene (A546T instead of P501T). Therefore, it is unclear whether different mutations could result in the same dystrophy or whether we are dealing with clinical heterogeneity of LCDIIIA.

Amniotic membrane transplantation in severe bacterial keratitis.

Purpose: To determine whether a combination of early amniotic membrane transplantation (AMT) and early topical corticosteroid treatment could be a safe adjuvant therapy during antibacterial treatment in severe bacterial keratitis (BK) for relieving pain, avoiding iatrogenic epithelial toxicity, and allowing earlier use of topical steroids. Methods: In a prospective noncomparative case series, 12 patients with severe microscopically-proven BK were treated with immediate maximal topical antibiotics followed by AMT at 48 hours (single-layer epithelial side-down or multilayer epithelial side-up), plus topical steroid treatment at 72 hours. Pain relief (NRS-11 numeric rating pain scale) and the corneal epithelium healing were measured. Results: The follow-up rate was 7.5 person-months, with AMT performed once in 2 patients and twice in 10 patients with BK caused by Pseudomonas aeruginosa (5), Klebsiella pneumoniae (1), Moraxella cattharalis (1), Staphylococcus aureus (1), Staphylococcus epidermidis (2), or Streptococcus pneumoniae (1). A significant decrease in the pain score was noted from the admission day (median, 8; range, 7-10) to shortly after AMT (at day 3: median, 2; range, 1-3). Epithelial healing was achieved between 8 and 45 days (mean, 25.5 ± 9.7 days). Neither perforation nor neovascularization was observed. Conclusions: Early AMT combined with topical corticosteroid in severe BK provides immediate pain relief and allows epithelial healing.

Clinical outcome of eight BIGH3-linked corneal dystrophies

OBJECTIVE To determine whether the mutational pattern of BIGH3-linked corneal dystrophies (CDs) can accurately predict the clinical course of the disease and be helpful in planning adequate surgical treatment. DESIGN Retrospective noncomparative case series. PARTICIPANTS Chart review of 73 patients (110 eyes) with recently confirmed BIGH3 mutations who underwent a penetrating keratoplasty (PK) from 1978 through 1999. Diagnoses included Thiel-Benhke CD (TBCD/R555Q) (13 eyes), classic granular CD (CGCD/R555W) (28 eyes), superficial variant of granular dystrophy (SVGD/R124 l) (27 eyes), lattice CD type I (LCDI/R124C) (20 eyes), Avellino CD (ACD/R124H) (2 eyes), H626R-lattice dystrophy (LCD/H626R) (6 eyes), and two novel dystrophies: a French variant of granular dystrophy (FVGD/R124 l+DT125-DE126) (9 eyes) and a French lattice CD type IIIA (LCDIIIA/A546T) (5 eyes). METHODS The mutation of the BIGH3 gene was characterized for all patients. Clinical data were reviewed for each patient, and included age at first PK and elapsed time before significant recurrence (as defined by a severe decrease in best-corrected visual acuity related to recurrent deposits in the graft). MAIN OUTCOME MEASURES Mean age at first PK and delay before a significant recurrence. RESULTS Mutational pattern was highly correlated with the clinical course of each dystrophy. According to the genetic mutation, two groups with different prognosis were identified. Group 1 was defined by the presence of the FVGD/R124 l+DT125-DE126 and SVGD/R124 l mutations and was characterized by the early need for treatment and early recurrence of deposits. Group 2 was molecularly defined by the presence of any of the following mutations: LCDI/R124C, CGCD/R555W, LCDIIIA/A546T, TBCD/R555Q, and LCD/H626R. In group 2, mean age at first treatment was older, and delay before a significant recurrence was longer as compared with group 1 (P = 0.0001). CONCLUSIONS These results demonstrate that there is a direct correlation between the molecular defect and the clinical course of BIGH3-linked CDs. They also indicate that molecular characterization of the genetic defect will help predict and design adequate surgical treatment for patients with ambiguous clinical diagnosis.

Clinical, histologic, and ultrastructural features of the corneal dystrophy caused by the R124L mutation of the BIGH3 gene

OBJECTIVE This study was designed to describe the clinical, histologic, and ultrastructural features of the corneal dystrophy associated with the R124L mutation of the BIGH3 gene. DESIGN Retrospective clinical and histologic review of a new genetic mutation. PARTICIPANTS Thirty-four patients from five unrelated French families with corneal dystrophy caused by the R124L mutation of the BIGH3 gene were studied at the clinical, histologic, and ultrastructural levels. Records of patients carrying this mutation were compared with those from three unrelated patients with corneal dystrophy of Bowmans layer (CDB) type 2 (R555Q mutation) and from three unrelated patients with classic corneal granular dystrophy (R555W mutation). INTERVENTION The mutational genetic status of the BIGH3 gene was determined for each patient, and the histologic and ultrastructural data available after corneal graft were analyzed. MAIN OUTCOMES MEASURES Genomic DNA was extracted from peripheral blood leukocytes. Exons 4 and 12 of the BIGH3 gene were amplified by the polymerase chain reaction (PCR), and the PCR products were directly sequenced. RESULTS All 34 patients with the R124L mutation displayed the clinical, histologic, and electron microscopic features of the dystrophy previously described as a superficial variant of corneal granular dystrophy. Combining molecular genetics with clinical and histologic findings established a clear distinction between the R555Q and R555W dystrophies. CONCLUSIONS The R124L mutation of the BIGH3 gene is associated with specific clinical and morphologic criteria. This indicates that molecular studies are needed for an adequate classification of corneal dystrophies. All criteria are presently available to segregate the dystrophy caused by the R124L mutation (known as CDB1) from the dystrophy caused by the R555Q mutation (known as CDB2).

Phototherapeutic keratectomy for BIGH3-linked corneal dystrophy recurring after penetrating keratoplasty

PURPOSE To determine visual results and report side effects and complications after phototherapeutic keratectomy (PTK) for BIGH3-linked corneal dystrophy recurring after penetrating keratoplasty. DESIGN Retrospective noncomparative case series. PARTICIPANTS Forty-two excimer laser PTK procedures were performed in 42 eyes of 29 patients with BIGH3-linked corneal dystrophies. Genetic status of all patients was determined and allowed us to assess an unambiguous diagnosis. Preoperative diagnoses included LCDIIIA/A546T (1 eye), R124 l+DT125-DE126 (4 eyes), GICD/R555W (14 eyes), LCDI/R124C (6 eyes), SGD/R124 l (16 eyes), and CDBII/R555Q (1 eye). INTERVENTION Two excimer lasers (Summit Excimed UV 200, Summit Technology, Waltham, MA and Nidek EC 5000, Nidek, Inc., Gamagori, Japan) were used to perform all PTKs. Indications for performing PTK after a graft were severe decrease of the best-corrected visual acuity (BCVA) related to recurrent corneal deposits and/or painful recurrent epithelial erosions. MAIN OUTCOME MEASURES Preoperative and postoperative BCVA were analyzed, significant recurrences after treatment were noted, and postoperative complications were recorded. RESULTS Mean preoperative BCVA was 0.2 +/- 0.12 in the decimal chart, mean postoperative BCVA was 0.52 +/- 0.16 with a mean follow-up of 3.13 +/- 1.77 years (range, 0.3-6.65 years). Visual acuity was significantly improved after surgery (P < 0.05). The magnitude of the change in visual acuity was dependent on the mutation (P < 0.001). Seven symptomatic recurrences were observed. One regressive graft rejection and 4 cases of severe postoperative haze were observed. No other complications were noted. CONCLUSIONS PTK is a simple, safe, and efficient technique for the treatment of recurrent corneal dystrophies; in many cases it prevents or delays the major incumbent problems of repeated grafting.

Persistent corneal opacity after oral isotretinoin therapy for acne.

This case report describes a case of persistent corneal opacity after oral absorption of isotretinoin. Isotretinoin has ocular side effect. These effects generally have no influence on visual acuity, although serious ocular adverse reactions have been reported. Isotretinoin should be discontinued if these symptoms occur. Appearance of hundreds or thousands of fine, rounded, white to gray lesions of various sizes was previously related to the use of isotretinoin therapy. Lesions were localized in the superficial stroma of the cornea (1). These side effects disappeared once the drug was discontinued in all previously reported cases (1). This patient developed these typical corneal lesions, but they have persisted for 6 years after the isotretinoin was discontinued.

Retinal angioma in a patient with Cowden disease

PURPOSE To report a rare case of ocular localization of Cowden disease. DESIGN Case report. METHODS A 50-year-old woman with a history of multiple tumors was diagnosed with Cowden disease. A PTEN gene mutation was found. Visual acuity of the left eye had decreased 2 years before diagnosis. RESULTS Visual acuity was 20/20 in the right eye and 20/200 in the left eye. Right eye fundus examination showed an epiretinal membrane associated with a peripheral and temporal inferior angiomatous lesion. Treatment consisted of cryoapplication and surgical removal of the epiretinal membrane after central vitrectomy. Although the anatomic result was satisfactory, the patients visual acuity remained unchanged. CONCLUSIONS Hamartomatous ocular lesions have been described in Cowden disease. We are unaware, however, of such retinal angiomatous lesions in patients with PTEN gene mutations.

The use of impression cytology in the follow‐up of severe ocular burns

Aims: To evaluate by impression cytology (IC) the expression of the MHC class II inflammatory marker HLA-DR by the conjunctival epithelium, the cytological modifications of the conjunctival surface according to the Nelson’s classification, and the eventual correlation between the two after severe ocular burns. Methods: A total of 24 patients (24 eyes) who presented with severe ocular burns underwent IC. We compared them with 18 healthy eyes. HLA-DR expression was studied by flow cytometry as well as the conjunctival histology evaluated with the Nelson’s classification from 2–24 months after the onset of burns. Results: There was a significant upregulation of the expression of HLA-DR in eyes with burns compared to the healthy population at 2 months (p<0.001), 6 months (p<0.001), 12 months (p = 0.019), 18 months (p = 0.0171) and 24 months (p = 0.01766). A significant difference was found between the Nelson grade in the pathological population and those of the healthy population at 2 months (p = 0.0157). HLA-DR upregulation was significantly correlated with the Nelson’s grades between 2 months (r = 0.69, p<0.0001) and 6 months (r = 0.61, p = 0.0001). Conclusion: The IC technique can act as a useful tool for following-up ocular surface inflammation after severe ocular burns.

Etude ultrastructurale des membranes épirétiniennes idiopathiques colorées au bleu trypan : Etude prospective à propos de 15 cas

INTRODUCTION Idiopathic epiretinal membrane results from detachment of the posterior hyaloid and is believed to be related to naturally occurring defects in the internal limiting membrane (ILM) of the retina. Vitrectomy and peeling are the treatment of choice. Trypan blue 0.15% (TB) stains epiretinal membrane and internal limiting membrane. It allows selective and complete removal, facilitating surgery, with less retinal damage. An ultrastructural study was conducted showing ultrastructural features of idiopathic epiretinal membranes (ERM) and those of the internal limiting membrane and its connections with the retinal side. MATERIAL AND METHODS After pars plana vitrectomy and induction of posterior vitreous detachment, 0.2 ml TB 0.15% was injected over the ERM in an air-filled eye. The stained tissue was peeled with intraocular forceps. Specimens were at once collected in 4% glutaraldehyde for a transmission electron microscopy study. RESULTS TB may allow complete and easier ERM and ILM peeling. The staining does not present toxic effects. The major cellular contingent is represented by glial cells, participating actively in neocollagen synthesis. Their presence supports the hypothesis of a migratory movement of retinal cells toward the vitreoretinal side. CONCLUSION The presence of an intact internal limiting membrane, the absence of optical fibers belonging to the under retina, and the absence of any sign of apoptosis make TB a useful staining agent for ERM and ILM peeling.