Post-penetrating keratoplasty glaucoma: risk factors, management and visual outcome

Restoring the Ocular Integrity of Perforated Corneal Ulcer Using Living Surgical Donor Tissues Derived From Keratoplasty in the COVID-19 Pandemic

The coronavirus disease 2019 (COVID-19) caused an unprecedented crisis for corneal surgeons who were forced to strategize for an acute shortage of tissues. Here, we report the initial clinical outcomes of utilizing host corneal buttons derived from optical penetrating keratoplasties of pseudophakic bullous keratoplasty (PBK) patients. Two patients presented to our department with a perforated fungal corneal ulcer in one eye during the COVID-19 pandemic. One eye of each of the patients was operated on with non-vascularized host cut tissues preserved in glycerin. The tissues were secured using 10-0 nylon sutures. Good anatomical integrity was achieved in both eyes. An optical penetrating keratoplasty (PK) was done in both eyes after one year for visual rehabilitation, with a final visual acuity of 20/120 and 20/80, respectively, at six months. In conclusion, therapeutic PK using host tissues obtained from the recipients of optical PK is a safe and effective option to restore ocular integrity during a shortage of fresh or glycerol-preserved corneas. However, optical PK is required for the final visual rehabilitation.

Challenges in the complex management of post-keratoplasty glaucoma

Glaucoma is a serious complication after corneal transplantation and itself a common cause for graft failure and leading cause of vision loss post-keratoplasty due to corneal endothelial decompensation. Endothelial keratoplasty procedures like Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK) may be superior to penetrating keratoplasty (PK) regarding the incidence of elevated intraocular pressure (IOP) and development of glaucoma. There are indications that regardless of the method of keratoplasty, some corneal diseases like pseudophakic bullous keratopathy, corneal perforation, and graft rejection have a higher risk for developing post-keratoplasty glaucoma than keratoconus and corneal dystrophies and likewise respond less to IOP lowering therapy. In this review, the pathophysiology of post-keratoplasty glaucoma, the diagnostic tools with focus on different devices, and their limitations with regard to measuring IOP and the treatment modalities are presented.

Incidence and Risk Factors of Ocular Hypertension/Glaucoma After Descemet Stripping Automated Endothelial Keratoplasty

Purpose

To evaluate the incidence, demographics, associated risk factors, management and clinical outcomes of ocular hypertension/glaucoma after Descemet stripping automated endothelial keratoplasty (DSAEK).

Methods

A cohort review of 81 DSAEK cases was performed at Queen Victoria Hospital, United Kingdom. Patients with pre-existing glaucoma, transient increased IOP within the first 48 hours post-graft, additional post-transplant surgery, or failed to complete one year follow-up were excluded from the study. Ocular hypertension was defined as intraocular pressure (IOP) elevation >21mmHg or ≥6mmHg from baseline at any postoperative visit. The study looked at the incidence, risk factors, response to anti-glaucoma treatment, graft failure and best corrected visual acuity.

Results

The incidence of post-DSAEK ocular hypertension and glaucoma was 51.9% and 13.6%, respectively. Steroid-induced IOP elevation was the most frequent cause, with an incidence of 38.3%. Risk factors such as pseudophakia (p=0.024) and preoperative IOP>16 (p=0.003) were found to be associated with post-DSAEK ocular hypertension. Preoperative IOP>16 had 5.27 times risk of IOP elevation. Eyes with graft dislocation and/or detachment were significantly associated with post-DSAEK glaucoma (p=0.038). There was no negative effect of OHT on visual acuity and graft status.

Conclusion

Glaucoma and OHT are common postoperative complications of DSAEK. Although steroid-induced IOP elevation was the most frequent cause, there are other reasons associated with development of post-DSAEK glaucoma, including graft dislocation and detachment. Eyes with preoperative IOP>16 mm Hg may require a close monitoring of IOP. In addition, management by medical treatment results in good visual acuity and graft clarity.

Prevalence and risk factors to develop ocular hypertension and glaucoma after penetrating keratoplasty

OBJECTIVE

To determine the prevalence and factors associated with the development of ocular hypertension and glaucoma, in patients undergoing penetrating keratoplasty, in the Eye Clinic of the city of Bogotá.

METHOD

A retrospective cross-sectional study was conducted, and 130 eyes of patients undergoing penetrating keratoplasty were analyzed at the Eye Clinic in Bogotá, between January 2015 and August 2018. Demographic and clinical data were obtained, and it was determined by bivariate analysis, the association factors and the prevalence of the pathology under study.

RESULTS

Prevalence of ocular hypertension was 27.69% and glaucoma 10%. Average age 48.93 ± 18.63 years; higher frequency of presentation in men (61.5%). Statistically significant association factors were male sex (PR 2.59), presence of peripheral anterior synechiae (PR 1.83), history of trauma (PR 2.16), prior PK (PR 2.10) and graft failure (PR 2.04). Post-KP glaucoma only had statistically significant association with bullous keratopathy (PR 2.76).

CONCLUSIONS

Ocular hypertension and glaucoma had a high prevalence after penetrating keratoplasty, and the association factors were similar to those reported in other international studies. Knowing these factors, allows focusing surveillance and treatment in these patients to avoid blindness due to damage of the optic nerve or corneal graft.

Prevalence and risk factors to develop ocular hypertension and glaucoma after penetrating keratoplasty

OBJECTIVE

To determine the prevalence and factors associated with the development of ocular hypertension and glaucoma, in patients undergoing penetrating keratoplasty, in the Eye Clinic of the city of Bogotá.

METHOD

A retrospective cross-sectional study was conducted, and 130 eyes of patients undergoing penetrating keratoplasty were analyzed at the Eye Clinic in Bogotá, between January 2015 and August 2018. Demographic and clinical data were obtained, and it was determined by bivariate analysis, the association factors and the prevalence of the pathology under study.

RESULTS

Prevalence of ocular hypertension was 27.69% and glaucoma 10%. Average age 48.93 ± 18.63 years; higher frequency of presentation in men (61.5%). Statistically significant association factors were male sex (PR 2.59), presence of peripheral anterior synechiae (PR 1.83), history of trauma (PR 2.16), prior PK (PR 2.10) and graft failure (PR 2.04). Post-KP glaucoma only had statistically significant association with bullous keratopathy (PR 2.76).

CONCLUSIONS

Ocular hypertension and glaucoma had a high prevalence after penetrating keratoplasty, and the association factors were similar to those reported in other international studies. Knowing these factors, allows focusing surveillance and treatment in these patients to avoid blindness due to damage of the optic nerve or corneal graft.

Incidence, Risk Factors and Treatment Outcomes of Intraocular Hypertension and/or Glaucoma Post-Penetrating Keratoplasty: A 5-Year Lebanese Retrospective Descriptive Study

Purpose

Glaucoma is one of the most common complications post-penetrating keratoplasty (PK). In this study, we report the Incidence, risk factors and treatment outcomes of intraocular hypertension (IOH) or/and glaucoma post-penetrating keratoplasty (PKG).

Methods

A 5-year descriptive retrospective study, Lebanese patients who underwent PK at Beirut Eye & ENT Specialist Hospital, between 2012 and 2017, were included. Patients with history of glaucoma were excluded. IOH/PKG cases that necessitate treatment were identified and analyzed for the incidence, risk factors and treatment outcomes.

Results

A total of 189 eyes of 159 patients were included, with male/female ratio 1.6 and the mean age 47.2±21.3 years. Bullous keratopathy (BK) presented with a high mean age: 70.3 years while ectasia patients were the youngest: 36.5 years. 34.9% of eyes developed high IOP within a mean of 25 months of follow-up distributed between sub-groups of patient with corneal ectasia (22.5%), redo-PK (51.2%), bullous keratopathy (BK) (50%), keratitis (24.9%), and others (dystrophy, trauma …) (21.4%). High IOP developed in 67.4% of the diabetic patients. Visual acuity was less likely to improve in cases developing elevated IOP while postoperative complications were significantly high. In those refractory to medical treatment, trabeculectomy as a glaucoma surgery was effective in lowering the IOP. Combining procedures with PK was not a risk factor for glaucoma. Interrupted sutures and higher number of suturing were associated with increased IOP levels.

Conclusion

IOH developed in one out of three patients who underwent penetrating keratoplasty. DM, bullous keratopathy, infectious keratitis and redo-PK were highly associated with PKG, whereas high IOP was less likely to develop in cases with keratoconus. Glaucoma is considered a poor prognostic factor in patients post-PK.

Long-term Outcomes on de novo Ocular Hypertensive Response to Topical Corticosteroids After Corneal Transplantation

PURPOSE

To determine incidence, demographics, management, and outcomes of topical steroid-induced ocular hypertension after penetrating keratoplasty (PKP) and to establish effects on intraocular pressure (IOP) and graft rejection when alternate corticosteroids are used.

METHODS

A single-center, retrospective review of 568 consecutive PKPs performed between 1997 and 2010 was conducted. Data were collected on demographics, best-corrected visual acuity, surgical indications, lens status, IOP, postoperative management, and incidence of rejection.

RESULTS

Eighty eyes (14.1%) of 74 patients were included. The most common indication was keratoconus (28.8%). Twenty-seven eyes (33.8%) were phakic, 46 (57.4%) had a posterior chamber intraocular lens, and 7 (8.8%) had an anterior chamber intraocular lens. Mean postoperative IOP increase was only significant in the anterior chamber intraocular lens group (18.7 mm Hg, SD 10.4; P = 0.02). The average time for developing hypertension was 9.8 months (SD 14.8) postoperatively, with an average IOP increase of 13.3 mm Hg (SD 5.9). Prednisolone acetate 1% was switched to rimexolone 1% in 64 eyes (80%) and to fluorometholone 0.1% in 16 eyes (20%), which alone achieved IOP normalization in 26 eyes (32.5%) (P < 0.01). Fifty-four eyes (67.5%) required additional antiglaucoma medication. An average IOP reduction of 12.3 mm Hg (SD 6.9) was achieved at an average of 2.3 months (SD 5.2) after the switch. Seventeen eyes (21%) developed glaucoma and 13 eyes (16.3%) developed graft rejection after switching formulations, with no statistically significant differences between rimexolone and fluorometholone (P > 0.05).

CONCLUSIONS

The use of alternate topical corticosteroids may be considered in cases of steroid-induced ocular hypertension after PKP because they offer good antiinflammatory prophylaxis with reduced hypertensive response.

Contact Transscleral Cyclodiode Laser Treatment for Refractory Glaucoma After Penetrating Keratoplasty: Retrospective Long-term Outcomes

PRéCIS:: This is a retrospective study with long-term follow-up using transscleral cyclodiode laser photocoagulation (TCP) with low complication rate and good graft survival and intraocular pressure (IOP) control. Selective 180-degree TCP may offer a good IOP control with reduced complication rates.

PURPOSE

To study the long-term safety and efficacy of contact TCP in eyes with refractory glaucoma after penetrating keratoplasty (PKP).

PATIENTS AND METHODS

All consecutive patients who were treated with TCP for refractory glaucoma following PKP between March 1996 and February 2017 in a tertiary corneal transplantation service in the United Kingdom. Only patients with a follow-up of 5 years were included. Eligible patients were identified through the corneal transplantation service database. Medical records and database data were retrospectively analyzed and compared at 5 years from baseline.

RESULTS

In total, 28 eyes of 28 patients presented with a mean IOP of 30.4 mm Hg (SD, 7.5) at baseline despite maximally tolerated topical and systemic antiglaucoma medications. IOP was reduced significantly to 12.8 mm Hg (SD, 3.6) (P<0.0001) at 5 years with 100% of patients with a successfully controlled IOP (defined as ≤21 mm Hg). All patients had a clear graft at the beginning of the study period and at 5 years 60.7% (n=17) still presented clear grafts. The average number of topical glaucoma medication was reduced from 2.8 (SD, 0.8) to 1.7 (SD, 1.2) (P=0.019) at 5 years. Visual acuity remained stable in 67.9% of patients at 5-year endpoint. No complications (ie, hypotony or phthisis bulbi) were reported during the study period and the corneal graft failure rate remained low at 5 years (39.3%).

CONCLUSIONS

Cyclodiode laser treatment with initial selective 180-degree protocol seems to be an efficient therapeutic option in the management of patients with refractory glaucoma post-PKP when compared with other surgical alternatives. A selective 180-degree protocol seems to potentially reduce the rate of complications. Further randomized controlled studies are needed to compare outcomes with modified treatment's protocols and glaucoma drainage device.

Incidence and risk factors for postkeratoplasty glaucoma in tertiary care center, India

BACKGROUND

Glaucoma is the leading cause of blindness after penetrating keratoplasty (PK) and its early diagnosis and management is mandatory to salvage the graft.

AIMS

This study aimed to evaluate the incidence and risk factors for post penetrating keratoplasty glaucoma (PKG).

METHODS

Data of 155 eyes of 155 patients were reviewed retrospectively who underwent PK from March 2013 to February 2016. Data were analyzed from recipient records for recipient age, sex, indications, type of PK, lens status, recipient graft size or any additional procedure. Detailed ophthalmological examination was recorded for all cases including best corrected visual acuity (BCVA), slit lamp examination, intraocular pressure (IOP) by applanation tonometry or tonopen, central corneal thickness (CCT) and gonioscopy. IOP measurement records were reviewed at each visit of one week, two weeks,one, three and six months and if IOP was elevated (>22 mmHg) medical management was initiated. Uncontrolled IOP with antiglaucoma medication (AGM) required surgical management.

RESULTS

Overall incidence of raised IOP after PK was 32.25%. Increase in IOP post PK was reported mainly in 32 (64%) among age group >40 years. Raised IOP showed significant association with age group, indications of PK, recipient size and CCT (P value 0.00, 0.01, 0.00, 0.00) respectively. Two weeks after PK 46 (29.67%) patients reported an increase in IOP ,47(30.32 %) after 1 months, 33 (21.29%) at 3 months and 30 (19.35%) at 6 months. In 11 (39.28%) cases cataract was major long term complication seen in PKG cases. 35 (70%) cases of PKG were treated medically and 15 (30%) patients required surgical treatment.

CONCLUSION

Subjects with age group >40 years, corneal opacity, increased recepient size and increased CCT are risk factors for PKG. IOP monitoring in early post operative period especially one month after PK is mandatory to avoid graft failure due to PKG which is difficult to diagnose otherwise.

Glaucoma after corneal replacement

Glaucoma is a well-known complication after corneal transplantation surgery. Traditional corneal transplantation surgery, specifically penetrating keratoplasty, has been slowly replaced by the advent of new corneal transplantation procedures: primarily lamellar keratoplasties. There has also been an emergence of keratoprosthesis implants for eyes that are high risk of failure with penetrating keratoplasty. Consequently, there are different rates of glaucoma, pathogenesis, and potential treatment in the form of medical, laser, or surgical therapy.

Incidence and risk factors for post-penetrating keratoplasty glaucoma: A systematic review and meta-analysis

Objectives

To establish the incidence and risk factors for post penetrating keratoplasty glaucoma (PKKG).

Methods

Studies published between 1947 and 2016 regarding penetrating keratoplasty (PK) were identified using an electronic search and reviewed. For search purpose, PKKG was defined as ocular hypertension (> 21mmHg) after PK. The incidence and risk factors of PKKG were extracted for all studies. Pooled incidence, odd ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Results

Thirty studies reporting on 27146 patients were included in the analysis of the incidence and risk factors for PKKG. Exact PKKG definitions used in the literature could be classified in to three subgroups: I, ocular hypertension (> 21mmHg) after PK; II, I plus > 4 weeks medical treatment required; III, II plus treatment escalation among patients with preexisting glaucoma. Overall (Definition I) pooled incidence in all studies was 21.5% (95% CI 17.8%, 25.7%). The incidence varied according to different definitions. The highest incidence value was found when only studies using Goldmann tonometer were included (22.5%), while the lowest incidence was found when a strict definition was used and steroid-induced PPKG was excluded (12.1%). The incidence was higher in patients with preexisting glaucoma, bullous keratopathy (BK), aphakia, pseudophakia, failed graft, and surgical indication of trauma. A triple procedure (combined PK with extra capsular cataract extraction and intraocular lens implantation) was not identified as being associated with the increased risk for PKKG.

Conclusions

The overall pooled incidence of PKKG was 21.5%, but it varied according to the criteria used to define the presence of PPKG. Strong risk factors for PKKG included preexisting glaucoma and aphakia, while modest predictors included pseudophakia, regrafting, and preoperative diagnosis like BK and trauma. There may not be sufficient evidence to identify a significant association between a triple procedure and PKKG.

Glaucoma management after corneal transplantation surgeries

PURPOSE OF REVIEW

Intraocular pressure (IOP) elevation and glaucoma progression following corneal transplantation, specifically, penetrating keratoplasty, Descemet's stripping endothelial keratoplasty, and Boston keratoprosthesis, are well described causes of ocular morbidity. Depending on the procedure performed, the incidence of glaucoma is highly variable. Several etiologic factors have been identified, the most common being synechial angle closure and corticosteroid-induced IOP elevation. The purpose of this review is to describe the various treatment strategies for glaucoma following corneal transplantation.

RECENT FINDINGS

Medications and laser treatments are usually first-line therapies for postoperative IOP elevation. Surgical intervention, including filtering surgery and glaucoma drainage devices, may be necessary to control IOP and prevent progressive glaucomatous damage.

SUMMARY

Glaucoma is a common complication of corneal transplantation, and the degree of aggressiveness is often related to the indication for corneal surgery. Although postoperative IOP elevation may be controlled with medical therapy alone, refractory cases may require glaucoma surgery. In all cases, early detection and intervention are necessary to optimize patient outcomes.

Post penetrating keratoplasty glaucoma: cumulative effect of quantifiable risk factors

Purpose:

To ascertain the incidence, identify risk factors and calculate cumulative effect of risk factors in patients developing glaucoma following optical penetrating keratoplasty.

Materials and Methods:

We carried out retrospective analysis of 445 patients, those underwent optical PK and had a minimum follow up of 6 m. Data on post-operative intra-ocular pressure (IOP) recorded at 3, 6, 9, 12 and 18 m or more was analyzed. Various risk factors including age, sex, indications for penetrating keratoplasty, pre-existing glaucoma and type of surgical procedures performed were analyzed by using univariate analysis and logistic regression technique.

Results:

Ninety (21%) of eyes developed post-PK glaucoma. On applying logistic regression, age, sex, indication of surgery, pre-existing glaucoma were found to be significant risk factors for the development of post-PK glaucoma (P < 0.05). Using logistic regression equation the cumulative risk of developing post-PK glaucoma in an individual patient can be calculated.

Conclusions:

Male patients, aged more than 40 years, having opaque grafts as an indication and with pre-existing glaucoma were found to be higher risk of developing post-PK glaucoma. Patients at higher cumulative risk for development of post-PK glaucoma may be closely monitored during follow-up.

Corneal transplantation and glaucoma

Glaucoma is the leading cause of irreversible vision loss post-keratoplasty and an important cause of graft failure. With newer techniques, such as lamellar, endothelial, and laser-assisted keratoplasty as well as keratoprosthesis gaining popularity, clinicians will need to consider the incidence, risks, evaluation, and management of glaucoma for each type of keratoplasty when determining which type of transplant may be most appropriate. A comprehensive literature search of glaucoma in the setting of corneal transplantation was performed and serves as the basis for this review. Preexisting glaucoma and aphakia are notable risk factors. Patients that are candidates for deep anterior lamellar keratoplasty may benefit from reduced rates of post-keratoplasty glaucoma. Although glaucoma also complicates eyes with Descemet stripping endothelial keratoplasty, the severity is less and the intraocular pressure is more easily controlled when compared to penetrating keratoplasty. Endothelial keratoplasty creates unique perioperative issues mostly related to management of anterior chamber air bubbles.

Risk factors and incidence of ocular hypertension after penetrating keratoplasty

PURPOSE

Ocular hypertension is a potentially serious complication after penetrating keratoplasty (PKP). Our objective is to determine the risk factors, incidence, patient characteristics, response to pressure-lowering medical therapy, and graft outcome associated with elevation of intraocular pressure after PKP.

METHODS

One hundred forty-six consecutive eyes that had PKP between June 2001 and June 2003 were operated and managed at Hadassah-Hebrew University Medical Center. Chart review was performed seeking preoperative and postoperative data on risk factors for ocular hypertension after PKP. Univariate and logistic regression analysis were performed to identify significant risk factors.

RESULTS

After surgery, 70 eyes (47.9%) had at least 1 period of ocular hypertension, with a mean intraocular pressure (IOP) of 27.15±5.66 mm Hg. Ocular hypertension appeared after a mean postoperative period of 70.3±15.8 days, and continued for an average period of 15.6±2.0 days. In 35 eyes (23.9%), a second episode of IOP elevation was noted 212.2±46.8 days after the surgery. Logistic regression analysis revealed that preexisting glaucoma (P=0.009) and an additional surgical procedure combined with PKP (P=0.007) were the main factors predicting ocular hypertension after PKP. In 11 eyes (7.53%) the topical pressure-lowering therapy failed, and they required glaucoma filtering surgery.

CONCLUSIONS

The incidence of ocular hypertension after PKP is high, and at least 1 episode of high IOP was noted in almost half of our patients. A history of preexisting glaucoma and an additional surgical procedure combined with PKP were found to be significant factors predicting the occurrence of ocular hypertension.

Anterior segment analysis and intraocular pressure elevation after penetrating keratoplasty and posterior lamellar endothelial keratoplasty

BACKGROUND

Peripheral anterior synechiae (PAS) is a common problem after penetrating keratoplasty (PK) and leads to intraocular pressure (IOP) elevation. This study examines the risk factors for IOP elevation and post-keratoplasty glaucoma.

METHODS

A retrospective analysis was performed of 47 eyes following PK and of 65 eyes following Descemet's stripping endothelial keratoplasty (DSEK) between 2009 and 2011. The assessment included preoperative history of corneal disease and glaucoma, response to treatment, IOP, and visual acuity. Irido-trabecular contacts (ITC), the angle opening distance (AOD 500) and the anterior chamber angle (ACA 500) were calculated.

RESULTS

The incidences of IOP elevation and post-keratoplasty glaucoma were 27-36% and 10-29%, respectively. The incidence did not differ significantly between both procedures. Pre-existing glaucoma increased the risk for developing IOP elevation and post-DSEK glaucoma. Eyes with bullous keratopathy (BK) developed significantly more IOP elevation (p = 0.01, d.f. = 1, χ(2) = 6.11) and post-keratoplasty glaucoma (p = 0.01, d.f. = 1, χ(2) = 6.22) than eyes with Fuchs' endothelial dystrophy. Eyes with ITC developed post-keratoplasty glaucoma significantly more often than eyes without ITC (p = 0.01, d.f. = 1, χ(2) = 6.63).

CONCLUSION

IOP elevation and post-keratoplasty glaucoma showed a high incidence. Risk factors like pre-existing glaucoma, BK and PAS elevated the rate of IOP elevation and post-keratoplasty glaucoma for both procedures.

[Post-penetrating keratoplasty glaucoma management: report of 73 cases]

PURPOSE

To report our experience in the therapeutic management of post-penetrating keratoplasty glaucoma.

INTRODUCTION

Post-penetrating keratoplasty (PK) glaucoma is a true threat to visual prognosis. Therapeutic modalities are many, but the absence of a well-defined decision tree and the variable results of the various techniques renders management very difficult.

PATIENTS AND METHODS

This is a retrospective study including 73 eyes of 71 patients undergoing a penetrating keratoplasty. Patients who developed post-operative ocular hypertension were treated first with eye drops. In the case of failure, surgical procedures were recommended including trabeculectomy or glaucoma drainage devices. The intraocular pressure (IOP) assessed with applanation tonometer, side effects and graft failure were monitored.

RESULTS

The first medical treatment used for all patients was a betablocker, which allowed control of intraocular pressure in 80.6 % of eyes. Ahmed glaucoma valve was used in two cases with success and without graft failure. Trabeculectomy was necessary for five patients, three of whom developed immunological graft rejection within 6 to 9 months. We also observed that late ocular hypertension was statistically related to anatomic graft failure, independently of other preoperative factors.

DISCUSSION AND CONCLUSION

Although hypotensive medication is still the first treatment for ocular hypertension after penetrating keratoplasty, a surgical procedure is sometimes required. Glaucoma drainage devices and trabeculectomy are widely practiced, leading to good outcomes, with the risk of rejection lower in cases involving mitomycin C. Cyclodestructive procedures should be reserved for surgical failures with significant visual loss.

Intraocular pressure elevation and post-DSEK glaucoma after Descemet`s stripping endothelial keratoplasty

BACKGROUND

Intraocular pressure (IOP) elevation is a common problem in penetrating keratoplasty (PK), and possibly leads to graft failure. IOP elevation and secondary glaucoma may also be present after Descemet`s stripping endothelial keratoplasty (DSEK). This retrospective study analyzes the risk factors for IOP elevation and the functional outcome in those patients with post-DSEK glaucoma.

METHODS

A retrospective analysis of case records of 72 DSEKs between 2007 and 2010 was performed. A total of 59 operated eyes were included. The assessment included the pre-operative history of corneal disease and glaucoma. Furthermore, the response to antiglaucoma treatment, the graft failure, the IOP, and visual acuity development were evaluated.

RESULTS

The incidence of IOP elevation was 28.8 % and of post-DSEK glaucoma 11.9 %. Steroid-induced IOP elevation was the most frequent cause, with an incidence of 18.6 %. Patients with pre-existing glaucoma showed a significantly higher risk of developing IOP elevation, steroid-induced glaucoma and post-DSEK glaucoma (p = 0.006, p = 0.023, p = 0.009). In all cases, IOP elevation was treated effectively by tapering down steroid medication and initiating or increasing antiglaucoma medication. Visual acuity after 6 and 12 months improved significantly in cases with and without pre-existing glaucoma (p < 0.0001). After 24 months, clear grafts were achieved in 53 eyes (89.9 %). There was no significant difference in graft failure rates between cases with or without pre-existing glaucoma (p = 0.581) and with or without post-DSEK glaucoma (p = 0.306).

CONCLUSIONS

IOP elevation after DSEK shows a high incidence. Pre-existing glaucoma increased the risk of developing IOP elevation and post-DSEK glaucoma. Although steroid-induced IOP elevation was the most frequent cause and could be treated effectively by tapering down steroid medication; there are other reasons why post-DSEK glaucoma developed. Management by medical treatment results in good visual acuity and graft survival.

Glaucoma and corneal transplant procedures

Glaucoma after corneal transplantation is a leading cause of ocular morbidity after penetrating keratoplasty. The incidence reported is highly variable and a number of etiologic factors have been identified. A number of treatment options are available; surgical intervention for IOP control is associated with a high incidence of graft failure. IOP elevation is less frequently seen following deep anterior lamellar keratoplasty. Descemet's striping-automated endothelial keratoplasty is also associated with postprocedure intraocular pressure elevation and secondary glaucoma and presents unique surgical challenges in patients with preexisting glaucoma surgeries. Glaucoma exists in up to three-quarters of patients who undergo keratoprosthesis surgery and the management if often challenging. The aim of this paper is to highlight the incidence, etiology, and management of glaucoma following different corneal transplant procedures. It also focuses on the challenges in the diagnosis of glaucoma and intraocular pressure monitoring in this group of patients.

Glaucoma and corneal transplant procedures

Glaucoma after corneal transplantation is a leading cause of ocular morbidity after penetrating keratoplasty. The incidence reported is highly variable and a number of etiologic factors have been identified. A number of treatment options are available; surgical intervention for IOP control is associated with a high incidence of graft failure. IOP elevation is less frequently seen following deep anterior lamellar keratoplasty. Descemet's striping-automated endothelial keratoplasty is also associated with postprocedure intraocular pressure elevation and secondary glaucoma and presents unique surgical challenges in patients with preexisting glaucoma surgeries. Glaucoma exists in up to three-quarters of patients who undergo keratoprosthesis surgery and the management if often challenging. The aim of this paper is to highlight the incidence, etiology, and management of glaucoma following different corneal transplant procedures. It also focuses on the challenges in the diagnosis of glaucoma and intraocular pressure monitoring in this group of patients.

Corneal graft survival and intraocular pressure control after descemet stripping automated endothelial keratoplasty in eyes with pre-existing glaucoma

PURPOSE

To describe the effect of Descemet stripping automated endothelial keratoplasty (DSAEK) on intraocular pressure (IOP) and corneal graft survival in eyes with pre-existing glaucoma or ocular hypertension.

DESIGN

Retrospective, observational case series.

METHODS

We performed a retrospective review of 184 eyes that underwent DSAEK from January 2007 through May 2009 at the Singapore National Eye Centre. Eyes with pre-existing glaucoma or ocular hypertension that underwent DSAEK were included, whereas those with a follow-up period of less than 12 months were excluded. Main outcome measures were graft failure and need for additional IOP-lowering treatment after DSAEK.

RESULTS

Forty-seven eyes (51% male; mean age, 66.6 years) with glaucoma underwent DSAEK and were followed-up for a mean of 27.3 ± 8.5 months. Before DSAEK, 60% were taking at least 1 topical IOP-lowering medication, whereas 14 eyes (30%) previously had undergone glaucoma filtration surgery. After DSAEK, visual acuity improved by a mean of 5.4 ± 3.7 Snellen lines. Seventeen percent of grafts failed at a mean of 12.8 ± 7.0 months. The mean IOP increased by 2.1 mm Hg to 16.0 ± 2.5 mm Hg, with 62% requiring additional IOP-lowering treatment and 28% needing filtration surgery at a mean of 9.3 months after DSAEK. Eyes without prior filtration surgery and eyes that underwent additional intraoperative procedures during DSAEK were 10 and 18 times more likely to require IOP-lowering treatment after DSAEK (P = .002 and P = .008), respectively.

CONCLUSIONS

With prompt and appropriate intervention, IOP in glaucomatous eyes undergoing DSAEK can be controlled with minimal increase after DSAEK. Eyes with previous filtration surgery require fewer medications to control elevated IOP than eyes that have not had previous surgery.

A 10.0-mm posterior lamellar graft for bullous keratopathy in a buphthalmic eye

PURPOSE

To report a case of Descemet stripping endothelial keratoplasty (DSEK) with a large posterior lamellar graft for the treatment of bullous keratopathy secondary to congenital glaucoma.

METHODS

Bullous keratopathy secondary to unilateral congenital glaucoma with buphthalmos in a 36-year-old man was treated with DSEK. A Descemet endothelium lamella of 10-mm diameter was excised by descemetorhexis. A regular sclerocorneal donor button of 12-mm diameter was manually split using the Melles technique, and a 10-mm diameter donor graft was punched. The graft was implanted as a folded "Taco" into the anterior chamber using forceps and fixed to the host bed using an intracameral air bubble.

RESULTS

: Immediately after DSEK, the graft showed a small peripheral dehiscence of 1 × 3 mm, which resolved within 2 days. During 30 months of follow-up, the endothelial graft remained well centered, clear, and without any signs of graft rejection. Visual acuity improved from perception of hand movement before operation to 0.2 at 30 months after DSEK. Endothelial cell loss was 33% at 18 months, 44% at 24 months, and 47% at 30 months after operation. Maximum intraocular pressure was 15 mm Hg preoperatively and 16 mm Hg at the last follow-up.

CONCLUSION

DSEK using a corneal graft of 10.0-mm diameter obtained from a normal-sized donor button can be performed safely and effectively in cases of unilateral buphthalmos and secondary corneal decompensation, where a large recipient cornea requires an equivalently sized graft and transplantation of large amounts of donor endothelium.

Diode Laser Transscleral Cyclophotocoagulation for the Treatment of Refractory Glaucoma After Penetrating Keratoplasty

PURPOSE

To evaluate the effect and safety of diode laser transscleral cyclophotocoagulation (TSCPC) in eyes with refractory glaucoma after penetrating keratoplasty (PK).

METHODS

Diode laser TSCPC was performed on 32 eyes of 32 patients with secondary glaucoma after penetrating keratoplasty. The mean follow-up period was 11.4 +/- 3.8 months (range, 6-20 months). The intraocular pressure (IOP), number of glaucoma medications, graft status, side effects, and complications of the procedure were all recorded during the follow-up period. The treatment was considered successful if after one cyclodiode treatment the IOP could be reduced to or below 22 mmHg with or without medication. The success rate of the diode laser treatment was analyzed by the Kaplan-Meier survival analysis method during the 6th and 12th months of the follow-up period and the end of the study. The decrease in drug requirement after laser treatment was analyzed by the Wilcoxon nonparametric test. Statistical significance was set at p < 0.05.

RESULTS

During the follow-up period, diode laser TSCPC reduced the IOP significantly. Our cumulative success rate was 56% at the end of the study. Cyclodiode treatment resulted in an IOP less than 22 mmHg in 97% of the eyes on the 6th month and 72% of the eyes on the 12th month with or without medication. The total retreatment rate of the study was 44%. More than one treatment was necessary, 8 times in the 1st month, 9 times in the 3rd month, 5 times in the 6th month and 3 times in the 12th month. The average number of antiglaucomatous drugs used was 2.8 before surgery and 1.2 after the 12th month follow-up period (p < 0.05). No eyes with graft failure after treatment were present. Visual acuity improved (> 2 Snellen lines of acuity) in two eyes and remained the same in the others. No serious side effects such as phthisis bulbi or hypotonia were observed.

CONCLUSIONS

Diode laser TSCPC appears to be a safe and effective procedure for the treatment of uncontrolled glaucoma secondary to penetrating keratoplasty.

Post-penetrating keratoplasty glaucoma

Post-penetrating keratoplasty (post-PK) glaucoma is an important cause of irreversible visual loss and graft failure. The etiology for this disorder is multifactorial, and with the use of new diagnostic equipment, it is now possible to elucidate the exact pathophysiology of this condition. A clear understanding of the various mechanisms that operate during different time frames following PK is essential to chalk out the appropriate management algorithms. The various issues with regard to its management, including the putative risk factors, intraocular pressure (IOP) assessment post-PK, difficulties in monitoring with regard to the visual fields and optic nerve evaluation, are discussed. A step-wise approach to management starting from the medical management to surgery with and without metabolites and the various cycloablative procedures in cases of failed filtering procedures and excessive perilimbal scarring is presented. Finally, the important issue of minimizing the incidence of glaucoma following PK, especially through the use of oversized grafts and iris tightening procedures in the form of concomitant iridoplasty are emphasized. It is important to weigh the risk-benefit ratio of any modality used in the treatment of this condition as procedures aimed at IOP reduction, namely trabeculectomy with antimetabolites, and glaucoma drainage devices can trigger graft rejection, whereas cyclodestructive procedures can not only cause graft failure but also precipitate phthisis bulbi. Watchful expectancy and optimal time of intervention can salvage both graft and vision in this challenging condition.

Surgical management of patients with combined glaucoma and corneal transplant surgery

The reasons for having combined glaucoma and corneal transplant surgery are myriad. Patients with corneal transplants have a high frequency of developing secondary glaucoma. Patients with preexisting glaucoma have even higher risk for developing glaucoma refractory to medical management after penetrating keratoplasty. The indication for corneal transplant affects the risk for developing postkeratoplasty glaucoma. The surgical treatment options for treating glaucoma include laser trabeculoplasty, cycloablation, trabeculectomy, and glaucoma drainage implants. In addition, the sequencing of glaucoma surgery relative to penetrating keratoplasty affects the outcome. Newer corneal transplant techniques may have a lower risk for developing secondary glaucoma.

The outcome of corneal grafting in patients with stromal keratitis of herpetic and non-herpetic origin

AIM

To evaluate the outcome of corneal grafting in patients with stromal keratitis of herpetic (HSK) and non-herpetic origin, using predefined diagnostic criteria and standardised postoperative therapeutic strategies.

METHODS

384 adult immunocompetent recipients of a corneal graft for herpetic (n = 186) or non-herpetic (n = 198) keratitis were followed up prospectively for up to 5 years.

RESULTS

The herpetic group displayed significantly more corneal vascularisation (p = 0.013), more epithelial defects (p = 0.049), lower corneal sensitivity (p <0.001), more graft rejection episodes (p = 0.002), and required larger grafts (p<0.001). However, the postoperative course of visual acuity, endothelial cell numerical density, and rate of graft failures were similar in both groups. After 5 years, cumulative probability of graft survival in HSK patients (40.85%) was similar to that observed in individuals with non-herpetic keratitis (50.15%; log rank = 0.874; relative risk: 1.04).

CONCLUSION

Despite a markedly higher preoperative risk profile in herpetic eyes, the functional outcomes of grafts in individuals with keratitis of herpetic or non-herpetic origin were similar. Probably the most important contribution is a consequent close follow up and a therapeutic strategy including systemic prophylaxis of viral recurrence and of graft rejection by well adopted local steroid therapy.

Long-term follow-up of intraocular pressure after penetrating keratoplasty for keratoconus and Fuchs' dystrophy: comparison of mechanical and Excimer laser trephination

PURPOSE

In the literature, the incidence of "secondary glaucoma" after penetrating keratoplasty (PK) is reported to range from 10% to 42%, depending on the diagnosis and the complexity of surgery. The purpose of this study was to assess the impact of the trephination method and simultaneous cataract surgery on the early and long-term intraocular pressure (IOP) after PK in eyes without previous surgery and glaucoma.

METHODS

Inclusion criteria for this prospective, randomized, longitudinal clinical study were (1) one surgeon (G.O.H.N.), (2) primary central PK, (3) Fuchs' dystrophy (7.5/7.6 mm) or keratoconus (8.0/8.1 mm), and (4) 16-bite double running diagonal suture. Exclusion criteria were (1) previous intraocular surgery, (2) preoperative glaucoma, and (3) postoperative trauma or endophthalmitis. In 170 patients (mean age, 51 +/- 18 years), PK was performed with use of either a 193-nm excimer laser (Excimer patients) along metal masks with eight orientation teeth/notches (50 keratoconus, 32 Fuchs') or motor trephination (Control patients; 53 keratoconus, 35 Fuchs'). In 27% of Excimer patients and 29% of Control patients a triple procedure was performed. The perioperative systemic acetazolamide application and the postoperative topical steroid therapy were standardized.

RESULTS

Maximal IOP during the first week after PK was 15.7 +/- 3.6 mm Hg (7% > 21; maximum, 28) in the Excimer group and 16.2 +/- 3.5 mm Hg (7% > 21; maximum, 30) in the Control group. During a mean follow-up of 3.4 +/- 1.3 years (maximal, 6.0), an IOP >21 mm Hg and/or application of topical antiglaucomatous medication was documented in 9% of Excimer patients versus 15% of Control patients (p = 0.32), in 15% of Fuchs' dystrophy versus 11% of keratoconus cases (p = 0.41), and in 11% of PK-only versus 15% of triple-procedure cases (p = 0.68). The IOP elevation started an average of 3.7 +/- 2.8 months (1 week to 9 months) after PK and ended an average of 6.5 +/- 3.1 months (6 weeks to 12 months) after PK. Mean maximal IOP during follow-up was 16.6 +/- 3.5 mm Hg (12-38) in the Excimer group and 17.2 +/- 3.2 mm Hg (12-30) in the Control group. Only one patient, who had undergone a triple procedure for Fuchs' dystrophy and had an elevated IOP, needed topical medication, from 32 months after PK to the end of follow-up. Glaucomatous optic disc damage was clinically detected in none of the patients.

CONCLUSIONS

Temporary secondary ocular hypertension after PK is rare in eyes with keratoconus or Fuchs' dystrophy without previous surgery. There was no detectable impact from the trephination method, the diagnosis, or simultaneous cataract surgery. With meticulous microsurgical technique, careful suturing, and peripheral iridotomy, the development of secondary glaucoma with disc cupping seems to be the exception.

Intraocular pressure after homologous penetrating keratoplasty

PURPOSE

To evaluate intraocular pressure (IOP) changes after homologous central penetrating keratoplasty in a noncomparative interventional case series.

METHODS

The study included 245 patients undergoing homologous central penetrating keratoplasty for keratoconus (n = 77), herpetic corneal scars (n = 29), nonherpetic corneal scars (n = 46), Fuchs endothelial dystrophy (n = 24), and secondary corneal endothelial decompensation caused by preceding intraocular operations (n = 69). Mean follow-up time was 30.4 +/- 18.7 months (range, 12.1-111.6 months). The same surgeon operated on all patients, and a peripheral iridotomy was routinely performed.

RESULTS

On the first postoperative day, IOP was significantly (P = 0.02) higher than that before keratoplasty. Taking the whole study group and taking the study groups separately, IOP measurements determined on the third postoperative day (P = 0.57), 1 week after surgery (P = 0.55), or later (P > 0.50) were not significantly different from the preoperative values. Eyes undergoing keratoplasty with cataract surgery and eyes undergoing keratoplasty without additional intraocular procedures did not vary significantly (P > 0.10) in IOP measurements. IOP did not differ significantly (P > 0.50) between eyes with an immunologic graft reaction (n = 29) and eyes without a reaction (n = 216). Acute angle-closure glaucoma was not detected in any of the patients. IOP measurements were statistically independent of suture type (P > 0.10), age (P > 0.05), preoperative and postoperative refractive error (P > 0.05), preoperative and postoperative corneal astigmatism (P > 0.10), preoperative and postoperative visual acuity (P > 0.10), diameter of graft and trephine (P > 0.15), and oversize of the graft (P > 0.50). Postoperative IOP measurements were significantly (P < 0.01) correlated with preoperative IOP values.

CONCLUSIONS

In eyes with a peripheral iridotomy performed during surgery, homologous central penetrating keratoplasty usually does not markedly change IOP. The main risk factor for postoperatively increased IOP is increased IOP before surgery.