Search PubMed⌕ Search

Biomedical subjects

M Assouline

Publications and source records attributed to M Assouline.

At least 19 recordsLinked to original sources
PubMed2001

Silicone punctal plug extrusion resulting from spontaneous dissection of canalicular mucosa: A clinical and histopathologic report.

PURPOSE: To report on an uncommon, previously unidentified, progressive silicone punctal plug extrusion. DESIGN: Small, retrospective case series. PARTICIPANTS: Five cases of punctal plug extrusion were identified among a series of 424 consecutive implantations. Histopathologic analysis was obtained in one case. One additional referred case was included in this report. RESULTS: The plugs were completely extruded from the punctal lumen 6 to 14 months after insertion after an otherwise uncomplicated postoperative course. All plugs were retained at the punctal margin by an encircling band of vascularized mucosal tissue originating from the canalicular lumen. The band consisted of connective tissue of canalicular mucosal origin, attached just below the junction of the punctal and canalicular epithelium. Mild mononuclear infiltration was present in the connective tissue component of the punctal region. There was no cytologic or architectural evidence of abnormal epithelium or connective tissue or of pyogenic granuloma. CONCLUSIONS: These observations suggest that progressive lacrimal punctal plug extrusion may relate to mucosal dissection by the plug edges. We speculate that mechanical stress induced by eyelid closure on an improperly sized or placed implant may result in plug tilt. Subsequent epithelial hyperplasia further enhances the tilt, and the sharper edge of the conical bulb promotes separation of the canalicular mucosa from its distal luminal aspect. At the completion of the extrusion, the mucosal surface is separated from its connective tissue base, at a proximal subpunctal level, causing formation of an encircling tissue band.

Adult↗
PubMed1999

Exophiala (Wangiella) dermatitidis keratitis after keratoplasty.

We report the first French case of an intraocular infection due to Exophiala (Wangiella) dermatitidis. Two months after a second corneal transplant for congenital hereditary endothelial dystrophy, the patient presented with ocular pain and corneal infiltrates leading to the graft rejection. Diagnosis was established by positive direct examination and cultures of the same fungus from corneal buttons, iris biopsies and ablated sutures.

Adult↗
PubMed1999

Matrix metalloproteinases in epithelia from human recurrent corneal erosion.

PURPOSE: To assay for the presence of matrix metalloproteinases (MMPs) in human corneal epithelium affected by recurrent erosion compared with that in normal corneal epithelium. METHODS: Corneal epithelial debridement samples were obtained from 13 patients with recurrent epithelial erosion. For control specimens, epithelia were obtained from healthy patients undergoing photorefractive keratectomy. Zymography was performed on all samples to identify MMPs. Immunolocalization of MMP-2, laminin, and collagen type VII was determined in two samples with human recurrent epithelial erosion and compared with that in control epithelium. RESULTS: Twelve of 13 erosion samples showed MMP-2 enzymatic activity; one of the 12 also showed MMP-9 activity. Only one erosion sample showed no MMP enzymatic activity. All normal control specimens were negative for MMP. Immunohistochemical analysis of two recurrent erosion samples showed MMP-2 presence in basal cells, whereas, in normal epithelium it was not detected. One sample with epithelial erosion showed laminin localization in basal epithelial cells and basal lamina. Type VII collagen localized in basal epithelial cells only in this sample. A second erosion sample showed localization of laminin and type VII collagen in basal epithelial cells only. Normal corneal epithelium showed presence of laminin and type VII collagen in basal epithelium and basal lamina. CONCLUSIONS: Matrix metalloproteinase-2 expression is upregulated in human epithelia affected by recurrent erosion compared with that in normal control samples. Immunolocalization studies suggest that this enzyme is concentrated in basal epithelial cells where it may play an important role in degradation of the epithelial anchoring system and the recurrent epithelial slippage and erosion observed in these patients.

Adult↗
PubMed1999

[Phototherapeutic keratectomy in the treatment of Groenouw's type I corneal dystrophy].

PURPOSE: This study was designed to investigate the therapeutic potential of phototherapeutic keratectomy (PTK) for the treatment of corneal granular dystrophy. PATIENTS AND METHODS: PTK was performed with the Excimed UV 200, (Summit Technology, Inc) on a series of 27 eyes of 22 patients with corneal granular dystrophy. Mean patients' age was 34.6 years. The mean follow-up period was 31 months (ranged from 6 to 52 months). The changes in best corrected visual acuity and spherical equivalent were evaluated at 6, 12, 18 and 24 months. RESULTS: All of patients achieved visual improvement. Mean preoperative best corrected visual acuity (BCVA) was 20/100 and mean postoperative BCVA was 20/30 at one year. The mean hyperopic shift caused by tissue ablation was +/- 2.8 D after one year. CONCLUSION: Corneal grafting was the standard treatment for visually disabling granular dystrophy, but PTK has significant advantages over this procedure and must now be the standard method of managing corneal granular dystrophy when intervention is required.

Adult↗
PubMed1998

B-mode-guided vector-A-mode versus A-mode biometry to determine axial length and intraocular lens power.

PURPOSE: To compare prospectively the reproducibility and accuracy of B-mode-guided biometry with those of A-scan biometry using a conventional A-mode probe to calculate intraocular lens (IOL) power. SETTING: Department of Ophthalmology, Hôtel-Dieu de Paris, France. METHODS: The axial length (AL) in 87 eyes of 72 candidates for cataract surgery was determined by B-mode-guided vector-A-mode and A-mode biometry using an Ophthascan S Ultrasound imager. Patients were assigned to one of two groups based on the B-mode biometry: nonmyopic (AL < 24.5 mm; n = 54) or myopic (AL > 24.5 mm; n = 33). Postoperative refractive results were compared with attempted values. RESULTS: Mean AL variance was significantly greater when using the A-mode than the B-mode: 0.157 mm +/- 0.260 (SD) versus 0.015 +/- 0.018 mm in the myopic group (P < .001) and 0.024 +/- 0.024 +/- 0.045 versus 0.009 +/- 0.011 mm in the nonmyopic group (P < .001). More eyes having B-mode biometry achieved a final refraction within +/- 0.50 diopter (D) of the attempted refraction (63 and 43%, respectively; P < .05). No deviation greater than 1.60 D was observed with the B-mode in the myopic or nonmyopic group. Three cases with a such a deviation (up to 2.24 D) would have been observed had A-mode-based biometry been chosen for the IOL power calculation. In the myopic group, attempted postoperative refraction was within +/- 0.50 D in 78% of eyes having B-mode biometry compared with 65% having A-mode. This difference was not statistically significant. CONCLUSION> These results suggest that the reproducibility and accuracy of AL measurements are significantly better with B-mode-guided A-mode biometry than with A-mode biometry in myopic and nonmyopic eyes.

Biometry↗
PubMed1998

A prospective randomized trial of topical soluble 0.1% indomethacin versus 0.1% diclofenac versus placebo for the control of pain following excimer laser photorefractive keratectomy.

BACKGROUND AND OBJECTIVE: To compare the safety and efficacy of topical nonsteroidal antiinflammatory drugs (NSAIDs) for the control of pain after excimer laser photorefractive keratectomy (PRK). PATIENTS AND METHODS: One hundred twenty informed patients were enrolled in a double-masked, randomized, comparative study and assigned to either 0.1% indomethacin, 0.1% diclofenac, or placebo treatment. Subjective postoperative pain, symptoms, re-epithelialization rate, and systemic medications were monitored for 2 days following photoablation. RESULTS: Compared with the placebo, 0.1% indomethacin solution significantly reduced pain on the day of surgery (D0) (P < .05), whereas 0.1% diclofenac did not reach a significant level (P = .46). At D0, analgesic intake by the oral route was significantly greater in the placebo group (P < .05). Severe photophobia was significantly less frequent in the group treated with 0.1% indomethacin (P < .05). Corneal wound healing was significantly delayed in the patients treated with 0.1% diclofenac at D2 as compared with other groups (P = .04). CONCLUSION: Topical 0.1% indomethacin solution helps control the pain induced by excimer laser photoablation of the cornea without any detrimental effect to the corneal epithelial wound healing.

Administration, Topical↗
PubMed1998

[Reis-Buckler dystrophy: therapeutic photo-ablation with the excimer laser].

PURPOSE: Reis-Buckler's corneal dystrophy consist of superficial reticulated opacities with recurring attacks of corneal erosion. Lamellar and penetrating keratoplasties were the traditional surgical means of improving recurrent erosions and vision but the dystrophy recurs following surgery. Phototherapeutic keratectomy (PTK) is now the standard method of managing this anterior corneal disease when intervention is required. MATERIAL AND METHODS: We have treated ten eyes with Reis-Buckler's dystrophy using Excimer laser PTK. RESULTS: All of patients achieved visual improvement (preoperative corrected visual acuity: average 0.3 +/- 0.2 SD, postoperative at one month 0.6 +/- 0.3 SD and 0.7 +/- 0.2 SD at one year. The refractive shift changed from a spherical equivalent of -0.92 D to a postoperative refraction of +1.80 D at one month and +1.65 D at one year.

Adult↗
PubMed1997

PMMA model of steep central islands induced by excimer laser photorefractive keratectomy.

We designed a polymethyl methacrylate (PMMA) model of refractive steep central islands (CIs) induced by PRK. A standardized photorefractive ablation procedure was performed using seven different excimer lasers on test PMMA specimens including 70 flat plates and 98 convex contact lenses. The resulting surface was analyzed by high-resolution confocal microscopy and computerized videokeratoscopy using both TMS-1 and CAS-2000 systems. A total of 50 (54.9%) CIs were observed using computerized videokeratoscopy. The rate of occurrence of CIs was significantly reduced by shock wave absorption (P = 0.0001), aspiration of fumes (P = 0.0044), and smaller diameter ablation (P = 0.0296). The diameter of the CIIs was significantly increased for broad-beam mode ablation (P = 0.016) and for larger ablation zones, (P = 0.042). The refractive power of CIs was significantly increased in the absence of a shock wave absorption system (P = 0.001). Only 20 (40%) of the CIs detected by the TMS-1 device were identified on CAS-2000 at a 0.5 diopter (D) scale resolution level. Shock wave induced deformation and subsequent dynamic alteration of convection forces applied to emitted particles may be the primary mechanism underlying the formation of CIs after PRK, regardless of any biological response of the ablated tissue. Reported rates and characteristics of CIs may largely depend upon the specific design of videokeratoscopes.

Astigmatism↗
PubMed1997

[Posterior scleral reinforcement surgery].

UNLABELLED: Scleral reinforcement is proposed to stabilize the visual acuity in patients with macular myopic staphyloma. Although many patients have been treated, this procedure is still debated. PURPOSE: Evaluation of the feasibility of scleral reinforcement and the operative risk of this procedure. PATIENTS AND METHODS: Patients were eligible for this prospective study patients with a clinical history of visual loss, staphyloma concerning the macular area associated with atrophic lesion and or lacquer cracks. Sixteen eyes in 13 successive patients have been operated on with a single band of PTFE. RESULTS: At the last examination, visual acuity was unchanged for 14 cases. In one case, an improvement of the vision was related to the disappearing of a macular detachment by shortening of the axial length. In one case, vision decline was associated with inadequate band position. Diplopia occurred in 2 cases. A choroidal detachment, and a vitreous haemorrhage disappeared without sequelae. CONCLUSION: An accurate technique is necessary to avoid operative risk. Further long term studies are needed to assess the benefit of scleral reinforcement.

Adult↗
PubMed1997

[Computerized video-keratoscopic analysis and cataract surgery by phacoemulsification. Predictive calculation of the power of the intraocular implant].

PURPOSE: The authors present the results of a prospective study of 125 consecutive cases of phacoemulsification, performed by a single surgeon, to assess the benefit of computerised videokeratoscopy for the improvement of the predictive calculation of the power of intraocular lenses (IOL). METHODS: Preoperative keratometry was determined by means of 3 concurrent techniques, including automated kerato-refractometry (AKR 2000, Nidek) and videokeratoscopy by TMS-1 (Tomey) and CAS-1 (EyeSys). The results of the IOL calculation by these 3 methods was compared postoperatively to the power of the actual IOL yielding emmetropia as calculated by the optical method based on the postop, refraction at the various time-points. RESULTS: Simulated values obtained with videokeratoscopy significantly reduced the refractive error at 1 postop, week (p = 0.001), one month (p = 0.002) and 3 months (p = 0.002) for the CAS1 and at 3 months (p = 0.002) for the TMS1, as compared to values obtained with conventional automated keratometry. The refractive error was significantly reduced with the CAS1 at one month (p = 0.001) and 3 months (p = 0.019) as compared to TMS1. CONCLUSION: The determination of the anterior curvature of the entrance pupil by videokeratoscopy significantly improves the predictive calculation of the IOL power.

Aged↗
PubMed1996

Full panretinal photocoagulation and early vitrectomy improve prognosis of florid diabetic retinopathy.

BACKGROUND: Florid diabetic retinopathy (FDR) is a rare form of proliferative diabetic retinopathy (PDR) that is characterized by a bilateral rapidly progressive, very severe ischemic retinopathy. Florid diabetic retinopathy was reported to carry a high risk of blindness. This study was conducted to determine whether visual prognosis of FDR can be improved by appropriate photocoagulation and surgical management. METHODS: The authors retrospectively studied 20 patients (40 eyes) who were treated from October 1978 to February 1994. Systemic risk factors, visual acuity, complete ocular examination, and fundus findings, as well as fluorescein angiography, were analyzed with respect to photocoagulation and surgical management. Mean follow-up was 3.6 years. RESULTS: All patients had poorly controlled type I diabetes (mean duration, 13.5 years), which often was associated with systemic complications. Mean initial visual acuity was equal to or better than 20/40 in 32 eyes (80%). During the course of the study, high-risk PDR was observed in 38 eyes (95%) and vitreous hemorrhage occurred in 26 eyes (65%). Extensive full subconfluent panretinal photocoagulation was performed completely in 37 eyes (92.5%). Vitrectomy was necessary in 15 eyes (37.5%). Macular edema was present in 30 eyes (75%). Major complications included retinal detachment that required surgery (2 eyes, 5%) and neovascular glaucoma (2 eyes, 5%). However, final visual acuity was equal to or better than 20/40 in 23 eyes (57.5%) and less than 5/200 in only 4 eyes (10%). CONCLUSION: These results suggest that aggressive treatment of FDR with extensive panretinal photocoagulation and early vitrectomy, when necessary, may result in a much better prognosis than has been reported previously.

Adolescent↗
PubMed1995

[Characteristics of corneal topography in candidates for surgery for myopia].

INTRODUCTION: Videokeratography analyses the corneal anterior topography. It is necessary in refractive surgery to estimate the anatomical effect of the surgery and to eliminate early Keratoconus. METHODOLOGY: Corneal anterior topography was studied on 70 consecutive patients (140 eyes) candidates for low myopia surgery (-1 to -6); 87 eyes were wearing regularly contact lenses. With the topographic analysis machine of EYESYS compagny, keratometry (Km) at 3 mm, astigmatism (delta K) at 3 mm, I-S value at 3 mm and 5 mm according to Rabinowitz method were measured in each eye. RESULTS: The average keratometry was 43.50 +/- 1.87 D. The average astigmatism was 0.909 +/- 0.75 D. 51 eyes presented an asymmetric corneal and among them 32 ware contact lenses regularly; 8 eyes out of 140 (6%) presented the association of an high central Keratometry value (> or = 47 D) and corneal asymmetry (I-S > 0.5 value). COMMENTS: The incidence of Keratoconus is higher in a candidate population for refractive surgery by self-selection. Its frequency is difficult to evaluate accurately because of the present limits for the diagnostic measures. In this population, it seems to represent about 6%. CONCLUSION: The videokeratography before refractive surgery is necessary to reveal corneal anterior topography abnormalities and to eliminate early Keratoconus.

Astigmatism↗
PubMed1994

Synthetic scleral reinforcement materials: I. Development and in vivo tissue biocompatibility response.

The surgical treatment of pathological myopia involves the placement of a band cut from donor sclera around the back of the globe to provide support and to prevent elongation that leads to retinal detachment and blindness. In the search for a synthetic material that would overcome the disadvantages of the donor tissue band, we tested 11 types of bands made from 14 polymers in rabbit eyes. Bands were cut from porous and solid materials, as well as porous materials coated with solids and solid materials with porous patches affixed to the posterior surface. Criteria for suitability and biocompatibility included ease of placement and suturing, stable positioning, and absence of long-term tissue response on a cellular level. Testing included evaluation by the surgeons performing the implantations, measurement of the distance between the band and the globe, determination of fibrous capsule thickness and amount of collagen deposition, and enumeration of macrophages accumulated at the band/capsule interface. Based on the results of these studies, two of the porous materials (expanded polytetrafluoroethylene and porous polyurethane fabric) and two of the composite materials (porous polyurethane fabric coated with polyacrylonitrile and silicone with microvilli cut into the posterior surface) were selected for further study.

Animals↗