[Filtering surgery in glaucoma: comparative study of three surgical approaches]. / Chirurgie filtrante dans le glaucome: étude comparative de trois approches chirurgicales.

INTRODUCTION: The multiple complications observed with trabeculectomy encouraged the re-emergence of non penetrating glaucoma surgery (NPGS) in the 1980's. Since then, several modifications have been developed in order to improve success rates and safety. We describe a new variation of deep sclerectomy (DS) in which we include an autologous corneal stromal implant soaked in mitomycin C and sutured to the scleral bed. Next, we compare intraocular pressure (IOP) at 2 years in three groups: I: DS; II: DS with autologous implant soaked in mitomycin C; III: conventional trabeculectomy. PATIENTS AND METHODS: All surgeries were performed by the same surgeon. There were 40, 22 and 15 eyes with medically uncontrolled primary open angle glaucoma (POAG) in groups I, II and III, respectively. All patients underwent the usual pre- and postoperative exams over 24 months. Selected patients underwent Visante OCT (Optical Coherence Tomography) (Carl Zeiss, Meditec, Inc. Germany) examination of their anterior segments. RESULT: Age and sex distribution in all three groups showed no statistical difference. Mean preoperative IOP was 24 ± 11 mmHg, 26 ± 14 mmHg and 25 ± 9 mmHg in group I, II and III, respectively (P>0.8). Mean postoperative IOP was 14 ± 3 mmHg, 10 ± 3 mmHg and 13 ± 4 mmHg (P=0.05) at six months; 16 ± 4 mmHg, 13 ± 3 mmHg and 11 ± 4 mmHg (P=0.02) at 12 months; and 15 ± 4 mmHg, 12 ± 3 mmHg and 14 ± 4 mmHg (P=0.2) at 24 months. Mean number of eye medications dropped from 1.85, 2.18 to 1.92 (P>0.05) preoperatively in group I, II, and III, respectively, to and 0.25, 0.05 to 0.18 (P=0.02) at 24 months. Patients with a visible implant under the bleb at 24 months had a better outcome. DISCUSSION: DS with autologous implant significantly reduced IOP at 12 and 24 months. The results seem better than those obtained with collagen implants, most likely due to the persistence of the corneal implant under the bleb at 2 years. Its non-resorption and the minimal fibrosis at the level of the scleral bed may be related to the fact that it is an autologous material which has been soaked with mitomycin C. CONCLUSION: DS with autologous implant soaked in mitomycin C, an inexpensive technique, demonstrates medium-term efficacy in the surgical management of POAG. Our results suggest that our technique may enhance both success rate and efficacy in lowering IOP. Further long-term studies are needed.

Pseudophakic ametropia managed with a phakic posterior chamber intraocular lens.

We report the use of a phakic posterior chamber intraocular lens (IOL) to correct pseudophakic ametropia. Two eyes of 2 patients developed ametropia after unilateral phacoemulsification and IOL implantation. The manifest refraction was -6.00 -0.50 x 50 in the first patient and +4.50 -1.00 x 15 in the second. Both patients were bothered by the induced anisometropia and had posterior chamber phakic IOL implantation in the pseudophakic eye. Postoperatively, uncorrected visual acuity improved from 20/400 to 20/30 in the first patient and from 20/200 to 20/40 in the second patient. The manifest refraction was -0.50 -0.75 x 55 and +1.50 -1.50 x 30, respectively. No complications were noted. Implantation of a phakic posterior chamber IOL may be an alternative to currently available methods of managing pseudophakic ametropia.

Characterization of epithelial downgrowth by confocal microscopy.

A 43-year-old white woman with a history of multiple ocular surgeries, including 4 penetrating keratoplasties, developed a concentric retrocorneal membrane at the graft periphery in the right eye. A white-light, tandem, scanning confocal microscope using a 24x/0.60 contact objective was used to examine the right eye in vivo. At the endothelial layer, confocal microscopic images similar to corneal epithelial cells were detected at the graft periphery. Unlike normal endothelial cells, the imaged cells demonstrated easily recognizable nuclei.

Confocal microscopy in lattice corneal dystrophy.

BACKGROUND: The purpose of the study was to assess the appearance of lattice corneal dystrophy by means of white-light confocal microscopy. METHODS: Two consecutive patients with lattice corneal dystrophy were prospectively examined. In vivo white-light tandem-scanning confocal microscopy was performed in the right eye of the first patient. Her left eye had undergone penetrating keratoplasty 4 years earlier. Histologic findings of the corneal button were compared with confocal microscopic findings of the right eye. The other patient was monocular and confocal microscopy was performed only in the non-seeing eye. RESULTS: In both patients, linear and branching structures with changing reflectivity and poorly demarcated margins were visualized in the stroma. The linear structures measured approximately 40-80 microm in width. CONCLUSION: Lattice corneal dystrophy presents characteristic linear images on confocal microscopy and should not be misdiagnosed as fungal hyphae in cases of corneal infection.

Confocal microscopy in posterior polymorphous corneal dystrophy.

PURPOSE: To report the distinguishing characteristics of posterior polymorphous corneal dystrophy (PPMD) using confocal microscopy. MATERIAL AND METHODS: Two consecutive patients with PPMD were prospectively examined using a white-light tandem scanning confocal microscope with a 24x/0.60 contact objective. RESULTS: At the level of Descement's membrane, roundish hyporeflective images were found in 1 patient. In the other patient, hyporeflective bands were detected. In both patients, patchy hyperreflective areas were identified. CONCLUSION: Confocal microscopy may allow diagnosis of PPMD by demonstrating the alterations in Descement's membrane. This technique is especially valuable in cases of endothelial decompensation, where slit-lamp and specular microscopy may fail to demonstrate changes in Descement's membrane.

Confocal microscopy in cornea guttata and Fuchs' endothelial dystrophy.

AIMS: To report the appearances of cornea guttata and Fuchs' endothelial dystrophy from white light confocal microscopy. METHODS: Seven eyes of four consecutive patients with cornea guttata were prospectively examined. Of the seven eyes, three also had corneal oedema (Fuchs' dystrophy). In vivo white light tandem scanning confocal microscopy was performed in all eyes. Results were compared with non-contact specular microscopy. RESULTS: Specular microscopy was precluded by corneal oedema in one eye. In the remaining six eyes, it demonstrated typical changes including pleomorphism, polymegathism, and the presence of guttae appearing as dark bodies, some with a central bright reflex. In all seven eyes, confocal microscopy revealed the presence of round hyporeflective images with an occasional central highlight at the level of the endothelium. Changes in cell morphology and size were readily appreciated. CONCLUSION: By comparison with specular microscopy, the hyporeflective images with an occasional central highlight seen on confocal microscopy are consistent with the presence of guttae. Confocal microscopy may confirm the diagnosis of cornea guttata and Fuchs' endothelial dystrophy by demonstrating the presence of guttae. This technique is especially valuable in cases of corneal oedema, where specular microscopy may fail to visualise the endothelium. However, specular microscopy should remain the method of choice to evaluate the endothelium, principally because it is easier to use.

Eyelid, conjunctival, and corneal findings in sleep apnea syndrome.

OBJECTIVE: To determine the prevalence of eyelid, conjunctival, and corneal findings in patients with sleep apnea syndrome (SAS). DESIGN: Case series. PARTICIPANTS: Seventy-two white patients referred for evaluation of suspected SAS. INTERVENTION: Complete examination of eyelids, conjunctiva, and cornea, including videokeratography. MAIN OUTCOME MEASURES: Spearman rank correlations were determined between the respiratory disturbance index (RDI) during night sleep, a value used to diagnose and grade SAS, and tear film break-up time, eyelid distraction distance, presence or absence of ocular irritation symptoms, blepharoptosis, floppy eyelids, lacrimal gland prolapse, keratoconus, and endothelial dystrophy. Each correlation was controlled for age and body mass index. RESULTS: According to the RDI, 44 (61 %) of the 72 patients had SAS. The RDI correlated positively with the eyelid distraction distance (P = 0.05), presence or absence of floppy eyelids (P = 0.01), and lacrimal gland prolapse (P = 0.01), and correlated negatively with tear film break-up time (P = 0.02). None of our patients with floppy eyelids had corneal abnormalities. One patient with SAS had bilateral keratoconus; another had bilateral Fuch endothelial dystrophy. CONCLUSIONS: Sleep apnea syndrome was significantly associated with reduced tear film break-up time, floppy eyelids, and lacrimal gland prolapse. However, ocular irritation symptoms and corneal involvement were rare among patients with SAS. These findings do not confirm previous studies that reported a high prevalence of corneal involvement in floppy eyelid syndrome.

Confocal microscopy in the iridocorneal endothelial syndrome.

AIMS: To report the appearances of iridocorneal endothelial (ICE) syndrome from real time, white light confocal microscopy. METHODS: Three consecutive patients, each with ICE syndrome, were examined prospectively. Corneal specular and confocal microscopic examinations were performed in all three patients. In the first patient, a penetrating keratoplasty was performed and the cornea was examined by light and scanning electron microscopy. No surgery was performed in the remaining two patients. RESULTS: In the first patient corneal oedema prevented endothelial specular microscopy. Confocal microscopy performed before penetrating keratoplasty successfully revealed abnormal epithelial-like endothelial cells. Histological examinations of the cornea following penetrating keratoplasty revealed the presence of multilayered endothelial cells with epithelial features (microvilli). In the remaining two patients, specular microscopy showed the presence of ICE cells with typical dark/light reversal. Confocal microscopy demonstrated groups of endothelial cells with epitheloid appearances. In all three patients, the contralateral endothelial appearance was normal by specular and confocal microscopy, except for moderate endothelial polymegathism in one patient. Epithelial-like endothelial cells were characterised by prominent nuclei on confocal microscopy. CONCLUSIONS: The application of confocal microscopy indicates that the ICE syndrome is characterised by epitheloid changes in the endothelium. Confocal microscopy may be used to diagnose the ICE syndrome by demonstrating epithelial-like endothelial cells with hyperreflective nuclei. This technique is especially of value in cases of corneal oedema, since specular microscopy may fail to image the endothelium in such cases.

Comparison of deep sclerectomy with collagen implant and trabeculectomy in open-angle glaucoma.

PURPOSE: To assess the efficacy and postoperative complications of deep sclerectomy with collagen implant (DSCI), a nonpenetrating filtration procedure. SETTING: Glaucoma Unit, Department of Ophthalmology, University of Lausanne, Switzerland. METHODS: Forty-four eyes of 44 patients with medically uncontrolled open-angle glaucoma had DSCI and a matched control group of 44 patients, trabeculectomy. A superficial scleral flap was raised and a deep sclerectomy performed in the scleral bed. Schlemm's canal was opened, and the cornea was dissected to Descemet's membrane. At that stage, aqueous filtered through the remaining trabeculo-Descemet's membrane. A collagen implant was sutured radially in the scleral bed; the scleral flap and conjunctiva were then closed. Examinations were performed before surgery and postoperatively at 1 and 7 days and 1, 2, 3, 6, 9, 12, 15, 18, and 24 months. RESULTS: The mean follow-up was 14.4 months +/- 6.3 (SD) (range 3 to 24 months). The mean preoperative intraoperative pressure (IOP) was 26.7 +/- 7.3 mm Hg. The mean postoperative IOP was 6.1 +/- 4.5 mm Hg at 1 day and 11.0 +/- 4.4 mm Hg at 1 week; it remained stable for the next 24 months. The success rate, defined as an IOP lower than 21.0 mm Hg without medication, was 69% in the DSCI group and 57% in the trabeculectomy group at 24 months postoperatively (P = .047). The number of postoperative complications was significantly lower in the DSCI group than in the trabeculectomy group. CONCLUSIONS: The success rate of DSCI may be comparable to that of trabeculectomy, with fewer complications.

Nd:Yag goniopuncture after deep sclerectomy with collagen implant.

BACKGROUND AND OBJECTIVE: To study the need, the safety and the success rate of Nd:Yag goniopuncture in eyes that underwent deep sclerectomy with collagen implant. PATIENTS AND METHODS: The first 100 patients that underwent deep sclerectomy with collagen implant were prospectively followed. Deep sclerectomy with collagen implant is a non-penetrating filtering surgery which allows filtration of aqueous from the anterior chamber to the subconjunctival space through a remaining trabeculo-Descemet's membrane without opening the anterior chamber. Goniopunctures with Nd:Yag laser were performed at the site of surgery when the filtration through the trabeculo-Descemet's membrane was considered to be insufficient with elevated intraocular pressure. The laser treatment was performed using a Lasag 15 gonioscopy contact lens (CGA1). Goniopunctures were performed using the free-running Q-switched mode with an energy ranging from 2 to 4 mJ. RESULTS: Of 100 patients who underwent deep sclerectomy with collagen implant, goniopunctures with Nd:Yag laser were performed in 41 patients (41%). The mean time between deep sclerectomy with collagen implant and goniopuncture was 9.9 months +/-1.2 months (+/-SE). The mean IOP before laser treatment was 22.2 mm +/-7.0 mm Hg and decreased to 12.5 mm +/-5.8 mm Hg immediately after laser treatment and remained stable for the next 2 years of follow-up. The immediate success rate of goniopuncture was 83%. Choroidal detachment occurred in two patients (5%). CONCLUSION: Nd:Yag goniopuncture is an efficient and safe treatment for low filtration through the trabeculo-Descemet's membrane after deep sclerectomy with collagen implant.

Differential diagnosis of linear corneal images on confocal microscopy.

PURPOSE: This study aimed to detect corneal conditions presenting with linear images on white light confocal microscopy and to analyze their distinguishing characteristics. METHODS: In 1996 and 1997, 153 eyes of 110 patients with various corneal conditions were examined. In vivo examination of the cornea was performed by using a white-light tandem scanning confocal microscope. Images were captured by using a video camera and stored on S-VHS video tapes. In this retrospective study, patient charts and confocal microscopic video records were reviewed. Conditions with linear images were looked for, and the images were analyzed and compared. RESULTS: The only structures presenting as linear images on confocal microscopy in normal subjects consisted of corneal nerves. The following pathologic conditions also had linear images on confocal microscopy: corneal vascularization, mycotic keratitis, lattice corneal dystrophy, and posterior polymorphous dystrophy. Each condition could be identified based on its reflectivity, delineation, size, branching pattern, and location in the cornea. CONCLUSION: Different corneal conditions present with linear images on confocal microscopy. Correct identification is critical to avoid misdiagnosis.

Interface inflammation after laser in situ keratomileusis. Sands of the Sahara syndrome.

PURPOSE: To determine the source of the interface debris that causes the interface inflammation known as "sands of the Sahara" after laser in situ keratomileusis (LASIK). SETTING: Department of Ophthalmology, LSU Eye Center, Louisiana State University Medical Center School of Medicine, New Orleans, USA. METHODS: A microkeratome (Automated Corneal Shaper) was used to make a LASIK flap in 8 eyes of 4 rabbits. In 4 eyes, the blade was used directly from the sterile pack; in the contralateral 4 eyes, the blade was cleaned prior to use. In vivo confocal microscopy of the corneas was performed 1 day after surgery. An unused, cleaned blade and an unused, uncleaned blade, as well as blades used in the rabbit eyes, were examined by scanning electron microscopy. RESULTS: Confocal microscopy revealed numerous fragments of debris surrounded by inflammatory cells in the LASIK flap interfaces created by blades taken directly from the sterile package. Interfaces created by the cleaned blades showed only rare, scattered bits of debris. Scanning electron microscopy of the unused blades showed debris on the uncleaned blade removed directly from the sterile package. CONCLUSION: Post-LASIK interface inflammation may be caused by debris on the microkeratome blade, although other sources are possible. The interface debris and inflammation can be reduced or eliminated by cleaning the microkeratome blade before use.

Characterization of fibrous retrocorneal membrane by confocal microscopy.

PURPOSE: To study the appearance of a fibrous retrocorneal membrane as seen by confocal microscopy. METHODS: A 67-year-old white woman with a history of multiple ocular surgeries, including repeated penetrating keratoplasties for aphakic bullous keratopathy, developed a retrocorneal membrane in the right eye. The membrane was first noticed 3 years after the last corneal transplant and remained stable subsequently. The patient was examined by in vivo white light tandem-scanning confocal microscopy. RESULTS: At the level of the retrocorneal membrane, confocal microscopy disclosed the presence of a hyperreflective fibrous-appearing layer. Normal endothelial cells could not be found. Anterior to the hyperreflective layer, activated keratocytes were identified. CONCLUSION: Confocal microscopy may allow noninvasive diagnosis of fibrous retrocorneal membrane. Additionally, our data suggest that the posterior keratocytes might play a role in the production and deposition of fibrous tissue.

Recurrent Meesmann's corneal epithelial dystrophy after penetrating keratoplasty.

PURPOSE: To characterize the histopathology of recurrent Meesmann's corneal epithelial dystrophy after penetrating keratoplasty. METHODS: Postmortem examination by light and electron microscopy of the eyes of an 84-year-old patient with Meesmann's dystrophy who underwent a penetrating keratoplasty in the right eye at age 74 years and a lamellar keratoplasty in the left eye at age 51 years. RESULTS: In the right eye, the characteristic features of Meesmann's dystrophy were demonstrated in both the donor and recipient corneas. The pathologic findings were limited to the corneal epithelium and included increased thickness, architectural disorganization, loss of cell polarity, increased amounts of intracellular glycogen, presence of intraepithelial microcysts containing degenerated cells, and in some cells, the presence of an electron-dense fibrillogranular material associated with disrupted cytoplasmic filaments. In the left eye, the corneal findings were consistent with but not specific for Meesmann's dystrophy. These included architectural disorganization, loss of cell polarity, presence of intraepithelial microcysts, and irregular thickening of the basement membrane in the donor cornea. CONCLUSION: Meesmann's corneal epithelial dystrophy is demonstrated to recur after penetrating keratoplasty. This finding suggests that the abnormalities that lead to the disease are localized to the corneal epithelial cells and not in the stroma, as previously proposed.

Management of conjunctival cicatrizing diseases and severe ocular surface dysfunction.

Physical or chemical injuries, infections, immunologic oculocutaneous disorders, drugs, and various systemic disorders may cause scarring of the conjunctiva and disturbances of the ocular surface. Trichiasis, lid margin malposition, and dry eye may result in persistent ocular irritation. The cornea may be primarily or secondarily involved. If severe, disturbances of the ocular surface may lead to significant visual impairment. Thorough evaluation of patients and of the underlying disease process is required for optimal management. Treatment may be challenging and should be comprehensive, combining medical measures and surgical correction of structural changes. Suppression of exogenous irritants, treatment of dry eye, antiinflammatory therapy, and immunosuppressants are paramount to control the underlying disease and allow optimal surgical results. Surgical correction of trichiasis and lid margin malposition, conjunctival grafting, mucous membrane transplantation, limbal stem cell transplantation, amniotic membrane transplantation, and penetrating keratoplasty help reestablish a physiologic ocular surface. Severe cases may require keratoprosthetics for visual rehabilitation. Corneal ulceration or perforation requires prompt attention to maintain ocular integrity. Special measures should be considered for patients who require cataract or glaucoma surgery.

Post-operative inflammation following deep sclerectomy with collagen implant versus standard trabeculectomy.

BACKGROUND: An investigation was carried out to compare post-operative inflammation following deep sclerectomy with collagen implant (DSCI) versus standard trabeculectomy. METHODS: In this prospective randomized study, 46 eyes of 46 Caucasian patients with medically uncontrolled chronic open-angle glaucoma and without previous glaucoma surgery underwent filtering surgery. Twenty-four eyes underwent DSCI. Twenty-two eyes underwent standard trabeculectomy. Pre- and post-operative flare, measured using laser flare photometry, were compared between the two groups. RESULTS: In both groups, the mean anterior chamber flare increased on the first post-operative day, then decreased progressively. DSCI was associated with lower flare measurements post-operatively. The difference was statistically significant up to 1 month post-operatively: 16.3 +/- 7.8 vs 72.5 +/- 38.9 (P < 0.001) at 1 day, 7.8 +/- 4.6 vs 44.7 +/- 29.2 (P < 0.001) at 1 week, 5.9 +/- 1.6 vs 7.0 +/- 2.8 (P = 0.012) at 1 month, 6.4 +/- 1.8 vs 6.5 +/- 1.9 (P = 0.77) at 2 months, 5.9 +/- 1.8 vs 6.1 +/- 1.6 (P = 0.65) at 3 months. CONCLUSION: Surgically induced inflammation can be reduced with DSCI. This may be due to the lack of iridectomy, irrigation, and penetration of the anterior chamber. Eyes at increased risk of post-operative inflammation, such as those with uveitic or traumatic glaucoma, may benefit from this procedure. Further studies are needed to evaluate the long-term functional and anatomical outcomes of DSCI.

Correlation between anterior chamber IgG/albumin concentrations and laser flare photometry in eyes with endogenous uveitis.

PURPOSE: To assess the correlation between laser flare measurements and anterior chamber IgG/albumin concentrations in eyes with mild to severe inflammation. MATERIALS AND METHODS: Seventeen eyes of 17 patients with endogenous uveitis underwent diagnostic paracentesis. IgG and albumin concentrations were determined from the samples of aqueous humor. Laser flare measurements were performed 1 h prior to paracentesis. The relationship between flare measurements and IgG/albumin concentrations was studied be plotting the data on a logarithmic scale. RESULTS: The flare measurement was 97.5+/-150.0 photons ms (mean +/- SD; range 4.3-528.7). The IgG concentration was 41.0+/-51.4 mg/dl mean +/- SD; range 0.2-200). The albumin concentration was 184.6+/-196.2 mg/dl (mean +/- SD; range 4-535). When plotted on a logarithmic scale, there was a statistically significant linear relationship between the flare measurements and the anterior chamber IgG or albumin concentrations (y = 1.14x-0.64, r= 0.87, p<0.001 for IgG; y = 1.39x-0.1, r= 0.94, p<0.001 for albumin). CONCLUSION: Laser flare photometry is an accurate technique for assessing anterior chamber inflammation. Flare measurements strongly correlate with blood-aqueous barrier breakdown.

Mutation hot spots in 5q31-linked corneal dystrophies.

Mutations in the BIGH3 gene on chromosome 5q31 cause four distinct autosomal dominant diseases of the human cornea: granular (Groenouw type I), Reis-Bücklers, lattice type I, and Avellino corneal dystrophies. All four diseases are characterized by both progressive accumulation of corneal deposits and eventual loss of vision. We have identified a specific recurrent missense mutation for each type of dystrophy, in 10 independently ascertained families. Genotype analysis with microsatellite markers surrounding the BIGH3 locus was performed in these 10 families and in 5 families reported previously. The affected haplotype could be determined in 10 of the 15 families and was different in each family. These data indicate that R555W, R124C, and R124H mutations occurred independently in several ethnic groups and that these mutations do not reflect a putative founder effect. Furthermore, this study confirms the specific importance of the R124 and R555 amino acids in the pathogenesis of autosomal dominant corneal dystrophies linked to 5q.

An ultrasound biomicroscopic study of eyes after deep sclerectomy with collagen implant.

OBJECTIVE: This study aimed to assess the natural history of eyes after deep sclerectomy with collagen implant (DSCI), a nonperforating glaucoma-filtering surgery. DESIGN: The design was a prospective, longitudinal, observational, and nonrandomized study. PARTICIPANTS: Forty-five eyes of 41 patients with medically uncontrolled open-angle glaucoma were studied. INTERVENTION: Deep sclerectomy with collagen implant was performed. MAIN OUTCOME MEASURES: Ultrasound biomicroscopy (UBM) of the sclerectomy site was performed 1, 2, 3, 6, 9, 12, and 18 months after surgery. The following parameters were assessed: length and height of the collagen implant, thickness of the residual trabeculodescemetic membrane, and bleb appearance. RESULTS: Mean intraocular pressure decreased from a preoperative value of 26.3 +/- 3.5 mmHg (mean +/- standard deviation) to a postoperative value of 16.6 +/- 3.1 mmHg (mean +/- standard deviation) at 18 months (P < 0.001). The UBM findings showed a subconjunctival filtration with a nonperforated thin trabeculodescemetic membrane. In 23 eyes (51%), a hypoechoic area in the suprachoroidal space was observed. The thickness of the trabeculodescemetic membrane was stable throughout the study with a mean value of 0.13 mm +/- 0.02 (mean +/- standard deviation) at 18 months. The collagen implant dissolved slowly within 6 to 9 months, leaving a tunnel in the sclera. CONCLUSIONS: The UBM findings are consistent with intraocular pressure lowering by aqueous filtration through the thin remaining trabeculodescemetic membrane to an area under the scleral flap, which was maintained open by the collagen implant. The authors speculate that aqueous humor then reached the subconjunctival space and, eventually, was filtered through the thin scleral wall into the suprachoroidal space. Complete resorption of the collagen implant occurred between 6 and 9 months after surgery.