摘要:

Purpose.To identify the influence of the underlying etiology on the outcome of therapeutic penetrating keratoplasty (PKP) in the management of corneal perforation, impending perforation or refractory corneal disease.Methods.A retrospective observational case series with 28 patients (28 eyes) was performed. Patients were divided in two subgroups, based on the underlying ocular disease leading to the therapeutic PKP. Group I consisted of 15 patients (54%) with an infectious etiology, the other 13 patients (46%) with a noninfectious condition belonged to group II. Mean follow up was 23.2 months (median 21 months).Results.An enucleation could be avoided in all but two cases. In group I, 12 of 15 (80%) grafts remained clear, compared with only 3 of 13 (23%) in group II (p= 0.0004). Visual acuity (VA) amelioration was achieved in 20 of 28 patients (71%). In group I the postoperative VA was significantly better than preoperatively (p= 0.002); however, in group II the improvement was only borderline significant (p= 0.05). Overall five out of ten (50%) patients with a therapeutic PKP in group I had an endothelial cell density ≥ 1900 cells/mm2at the time of their last specular microscopy.Conclusion.Our study demonstrates the importance of underlying etiology on the outcome of therapeutic PKP. Graft survival and postoperative visual acuity varied widely depending on the underlying ocular disease, and it was clear that therapeutic PKP has a much better prognosis in infectious conditions when compared with noninfectious conditions. We believe that these good results can justify the use of therapeutic PKP in selected cases of infectious keratitis.

ISSN:0277-3740    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Purpose.To determine the sensitivity, specificity, and predictive values of Gram and potassium hydroxide with calcofluor white (KOH+CFW) stains in the diagnosis of early and advanced microbial keratitis, a retrospective analysis of comparative data from a prospectively collected database was done.Methods.Patients with nonviral microbial keratitis seen at L.V. Prasad Eye Institute between February 1991 and December 1998 were included in the study. The type of bacteria seen on Gram stain was determined from 251 corneal scrapings from patients with early keratitis and 841 corneal scrapings from patients with advanced keratitis. The presence of fungi in corneal scrapings was determined by KOH+CFW stain of 114 and 363 scrapings from patients with early and advanced keratitis, respectively. The smear findings were compared with culture results to analyze specificity, sensitivity, and predictive values of the staining techniques.Results.The sensitivity of Gram stain in the detection of bacteria was 36.0% in early and 40.9% in advanced keratitis cases; however, the specificity was higher in both groups (84.9% and 87.1%, respectively). Comparatively, the sensitivity and specificity of fungal detection were higher using KOH+CFW in early (61.1% and 99.0%, respectively) as well as advanced keratitis (87.7% and 83.7%, respectively). Predictive values were high for KOH+CFW in fungus detection, while they were poor for Gram stain in bacteria detection. In advanced keratitis cases, the false positives were higher in fungal detection (16.3%) than in bacterial detection (10.3%), while the false negatives were significantly higher in bacterial detection compared with fungal detection (59.1% versus 12.3%,p< 0.0001). In early keratitis, on the other hand, both false positives and false negatives for bacterial detection were significantly higher than fungal detection.Conclusions.Decisions can reliably be based on KOH+CFW stain of corneal scrapings for initiation of antifungal therapy in mycotic keratitis. The results of Gram stain, on the other hand, have limited value in therapeutic decisions for bacterial keratitis. Therefore, the search for a better modality for early and efficient diagnosis of bacterial keratitis needs to continue.

ISSN:0277-3740    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Purpose.To analyze the influence of mechanical versus nonmechanical trephination of donor and host corneas on superficial, peripheral corneal neovascularization occurring after non–high-risk keratoplasty.Methods.Patients of the prospective Erlangen non–high-risk keratoplasty study with standardized corneal photographs taken preoperatively and 1 year later were analyzed (n = 184). Slides of these photographs were projected (magnification ×100) and corneal vessels graded in a standardized semiquantitative fashion into five categories with regard to limbus, sutures, and host-graft junction in each of 12 corneal sectors. Degree (total increase of grades in the 12 sectors) and maximal extent of corneal neovascularization (maximal centripetal extension of blood vessels) were analyzed. In 32 patients mechanical (17%) and in 152 nonmechanical trephination of host and donor tissue was performed (193-nm excimer laser, 83%). Statistical analysis was done using Fisher's exact and Mann-WhitneyUtest.Results.Corneal neovascularization within the first postoperative year was lower in the nonmechanical [73 of 152 (48%)] compared with mechanical trephination group [24 of 32 (75%);p< 0.01; Mann-WhitneyUtest]. Maximal extent of neovascularization (i.e., vessels reaching the interface or growing beyond) was not yet significantly different between nonmechanical (8%) and mechanical (17%) trephination (p= 0.074).Conclusions.Nonmechanical trephination using the 193-nm excimer laser in non–high-risk keratoplasties might reduce corneal neovascularization occurring within the first postoperative year. This indicates that in the non–high-risk setting, development of postoperative corneal neovascularization may be affected by the trephination technique and subsequent wound-healing response.

ISSN:0277-3740    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Purpose.To report the use of intracameral amphotericin B in the management of deep keratomycosis.Methods.Four patients with deep keratomycosis unresponsive to conventional medical treatment underwent repeated intracameral injections of 5 &mgr;g amphotericin B in 0.1 mL 5% dextrose through a paracentesis. Three to 13 intracameral injections were given to each patient over 6 to 36 days.Results.Three of the four patients had complete resolution of the ulcer. The fourth patient perforated and required evisceration.Conclusion.Preliminary experience suggests that intracameral injections of amphotericin B may have a role in the management of deep keratomycosis.

ISSN:0277-3740    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Purpose.To report a new technique of lamellar keratoplasty in a case of keratoglobus.Methods.A patient with bilateral keratoglobus with maximal thinning in the juxtalimbal periphery underwent a lamellar procedure in the right eye. The visual acuity was 3/60. Refraction was not possible due to severe irregular astigmatism, and the central pachymetry was 430 &mgr;m. A central 8.5 mm diameter lamellar dissection along with a peripheral intrastromal pocket up to the limbus was fashioned. The donor corneal button (12 mm) denuded of its endothelium was beveled at the periphery to create a flange. This flange was tucked into the peripheral pocket and the graft was sutured with interrupted nylon sutures.Results.No intra-or postoperative complication was encountered. Reepithelialization was complete within 1 week. At 1 month postoperatively, the preoperative keratometric astigmatism of >12 D decreased to <2.75 D. The spectacle-corrected visual acuity at 1 month was 6/18.Conclusions.This new technique of central lamellar keratoplasty with intralamellar tucking of the peripheral flange for keratoglobus not only provides optical clarity and tectonic support but also helps in preservation of the host limbal stem cells.

ISSN:0277-3740    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Purpose.To describe a technique and report results of tectonic lamellar keratoplasty using tissue harvested with a microkeratome from a corneoscleral rim mounted in an artificial anterior chamber system.Methods.A donor lenticule was prepared from a corneoscleral rim utilizing the Moria LSK-1 (Moria/Microtek Inc., Doylestown, PA, U.S.A.) microkeratome and artificial anterior chamber. This tissue was used in the procedures of 6 eyes of 6 patients requiring tectonic lamellar keratoplasty. Three eyes were in danger of imminent perforation due to corneal ulceration. Other indications for lamellar engraftment include persistent wound leak following cataract extraction, persistent epithelial defect following a Grade 4 chemical burn, and limbal dermoid.Results.A successful outcome, defined as restoration or preservation of globe integrity, vision, and intact epithelium, was achieved in all patients. Follow-up ranged from 2–8 months with a mean of 4.5 months.Conclusions.Donor lenticules prepared with the ALTK (Moria/Microtek Inc.) system can be used in the successful management of eyes requiring tectonic lamellar keratoplasty.

ISSN:0277-3740    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Purpose.To demonstrate the ability of the Dry Eye Questionnaire (DEQ) to characterize the frequency of ocular surface symptoms and their diurnal intensity in patients with Sjögren's syndrome (SS), keratoconjunctivitis sicca (KCS), and age-matched controls.Methods.One hundred patients with tear-deficient dry eye from Toronto Western Hospital were mailed the DEQ and the McMonnies' questionnaire (MQ). Age- and gender-matched controls were selected from an historical data set. The DEQ measured the habitual frequency, intensity, and impact of common ocular surface symptoms and asked questions about computer use, medications, and allergies.Results.Sixty-two dry eye subjects responded; 30 with SS and 32 with KCS. Compared with controls, SS subjects consistently reported the highest frequency and intensity of symptoms, followed by non-KCS subjects. The intensity of symptoms was significantly greater in the evening than in the morning among SS subjects for all symptoms except dryness and light sensitivity (p< 0.05). Sixty percent of SS subjects reported the need to stop daily activities and close their eyes due to dryness, burning, and light sensitivity.Conclusions.Symptoms of ocular irritation were frequent and intense among SS and KCS subjects. These symptoms often increased in intensity over the day, suggesting that open-eye conditions affect the progression of symptoms. Measurement of symptom frequency and diurnal intensity by the DEQ provides a sensitive tool that may be useful in clinical treatment trials for dry eye.

ISSN:0277-3740    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Purpose.To report baseline differences between eyes on key variables in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study cohort compared with a retrospectively assembled group of myopic contact lens wearers without ocular disease.Methods.A total of 1,079 keratoconus patients who had not undergone a penetrating keratoplasty in either eye before their baseline visit were enrolled and examined at baseline. Records from 330 contact lens-wearing myopes were reviewed. Corneal curvature (keratometry), visual acuity, refractive error (manifest refraction), and corneal scarring were measured.Results.The mean differences between keratoconic eyes are as follows (better eye–worse eye for each variable, separately). Flat keratometry: −3.59 ±4.46 D and steep keratometry: −4.35 ±4.41 D; high-contrast best-corrected visual acuity: 7.30 ±6.83 letters; low-contrast best-corrected visual acuity: 8.53 ±7.51 letters; high-contrast entrance visual acuity: 9.03 ±8.40 letters; low-contrast entrance visual acuity: 9.43 ±7.88 letters; spherical equivalent refractive error: 3.15 ±3.84 D; and refractive cylinder power 1.55 ±1.42 D. Twenty-one percent of the keratoconus patients had corneal scarring in only one eye. There is an association between patient-reported unilateral eye rubbing and greater asymmetry in corneal curvature, and between a history of unilateral eye trauma and greater asymmetry in corneal curvature and refractive error, with the rubbed/traumatized eye being the steeper eye most of the time.Conclusions.Keratoconus is asymmetric in the CLEK Study sample.

ISSN:0277-3740    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Purpose.To evaluate the effect of a new suturing technique on postkeratoplasty visual rehabilitation time and refractive error.Methods.Penetrating keratoplasty was performed on 17 eyes with keratoconus using a modified suturing technique. A donor button 8.0 mm in diameter was sutured into a 7.75-mm recipient bed with both deep and superficial sutures. The deep sutures consisted of either a single 16-bite 10-0 nylon running suture (n = 7) or eight interrupted 10-0 nylon cross-stitches (n = 10). These sutures were passed into the mid-stroma of the donor cornea and exited through the donor endothelium, then passed through the endothelium of the recipient cornea and exited from its mid-stroma. Thereby all parts of the deep sutures remained below the corneal surface. To further secure the surgical wound, in each case a running 16-bite 10-0 nylon superficial suture was also placed. Care was taken to maintain the bites of the superficial suture above the level of the deep sutures. The superficial suture was removed 3 months after surgery. Vision and refraction were recorded 1 day and 1 month postoperatively and 1 and 3 months after suture removal. A paired Studentttest was used to verify the significance of changes in visual acuity and refraction recorded at different examination times.Results.As early as 1 month after surgery, spectacle best-corrected visual acuity 20/40 or more and refractive astigmatism less than 4 diopters (D) were recorded in each eye and maintained with two exceptions at the later examination times. In two patients, postoperative astigmatism increased from 4.5 to 5 D after suture removal.Conclusions.Deep suturing allowed quick visual rehabilitation while minimizing postkeratoplasty astigmatism in the patients with keratoconus operated on in this series.

ISSN:0277-3740    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Purpose.To review outcomes of AlphaCor artificial cornea implantation in patients with and without a history of ocular herpes simplex virus (HSV) and to determine whether herpetic eye disease is an indication for AlphaCor surgery.Methods.Outcomes of the initial 40 implantations were reviewed and stratified by the presence of a history of ocular disease caused by HSV. Outcomes measures (complications, visual acuity gained) were compared.Results.Eight of the 40 AlphaCor implantations (20%) were in patients with a history of ocular HSV. Six of these eight patients (75%) developed melt-related complications after AlphaCor insertion. Half of the affected patients required removal of the AlphaCor and replacement with a donor corneal graft to restore ocular integrity. In comparison, only six of the 32 (18.8%) patients without HSV developed a melt after AlphaCor insertion. Patients with HSV with devices in situ exhibited a mean loss of 0.3 line of best-corrected visual acuity compared with the preoperative visual acuity, whereas patients without HSV exhibited a mean gain of 1.4 lines of best-corrected visual acuity.Conclusions.The extensive lamellar corneal surgery involved in AlphaCor implantation may precipitate reactivation of latent HSV such that reactivation and resultant inflammation reduce device biointegration and facilitate melting of corneal stromal tissue anterior to the device. Although there may be some benefit from systemic antiviral medication, the current series is not large enough to demonstrate such a benefit, and melting can occur despite medication. The statistically significant difference in outcomes between recipients of AlphaCor with and without HSV is evidence that a history of HSV should be an exclusion factor for AlphaCor surgery.

ISSN:0277-3740    

出版商:OVID    

年代:2002

数据来源: OVID