Preexisting and postoperative glaucoma in repeated corneal transplantation

A Detailed Analysis of Individuals Having Graft Failure After Corneal Transplantation

PURPOSE

To describe demographic and clinical characteristics of patients with graft failure after keratoplasty, determine the cause of graft failure and outcomes.

METHODS

The charts of patients between 2008-2013 in the Cornea Service at Wills Eye Hospital with a history of a corneal transplant before the end of 2012 were retrospectively reviewed. Included were patients who had graft failure after corneal transplantation and had at least one year of follow-up after transplantation. Penetrating keratoplasty (PK) and Descemet's stripping endothelial keratoplasty (DSEK) patients were analyzed separately.

RESULTS

A total of 186 eyes of 170 patients with graft failure after a PK (156) or DSEK (30) procedures were identified. The baseline characteristics included 100 female and 70 male patients with an age between 0 and 90 years (median 63 years). At the time of surgery, 38% had three or more systemic diseases and 68% were using three or more systemic medicines. Mean follow up time for PK was nearly four times of DSEK. Only 2 DSEK eyes (7%) underwent a 3rd DSEK graft, while 47 (30%) PK eyes underwent a 3rd PK and 15 (10%) PK eyes underwent more than three PK procedures.

CONCLUSIONS

Most DSEK failures occurred in 1st year, while graft failure in PKs is scattered over years. Failure in DSEK is mostly due to graft or surgical risk factors but in PK mostly due to factors in the host. DSEK does not appear to be as affected by the patients' demographic and clinical characteristics as much as PK.

The prophylactic value of TNF-α inhibitors against retinal cell apoptosis and optic nerve axon loss after corneal surgery or trauma

BACKGROUND AND PURPOSE

Late secondary glaucoma is an often-severe complication after acute events like anterior segment surgery, trauma and infection. TNF-α is a major mediator that is rapidly upregulated, diffusing also to the retina and causes apoptosis of the ganglion cells and degeneration of their optic nerve axons (mediating steps to glaucomatous damage). Anti-TNF-α antibodies are in animals very effective in protecting the retinal cells and the optic nerve-and might therefore be useful prophylactically against secondary glaucoma in future such patients. Here we evaluate (1) toxicity and (2) efficacy of two TNF-α inhibitors (adalimumab and infliximab), in rabbits by subconjunctival administration.

METHODS

For drug toxicity, animals with normal, unburned corneas were injected with adalimumab (0.4, 4, or 40 mg), or infliximab (1, 10, or 100 mg). For drug efficacy, other animals were subjected to alkali burn before such injection, or steroids (for control). The rabbits were evaluated clinically with slit lamp and photography, electroretinography, optical coherence tomography, and intraocular pressure manometry. A sub-set of eyes were stained ex vivo after 3 days for retinal cell apoptosis (TUNEL). In other experiments the optic nerves were evaluated by paraphenylenediamine staining after 50 or 90 days. Loss of retinal cells and optic nerve degeneration were quantified.

RESULTS

Subconjunctival administration of 0.4 mg or 4.0 mg adalimumab were well tolerated, whereas 40.0 mg was toxic to the retina. 1, 10, or 100 mg infliximab were also well tolerated. Analysis of the optic nerve axons after 50 days confirmed the safety of 4.0 mg adalimumab and of 100 mg infliximab. For efficacy, 4.0 mg adalimumab subconjunctivally in 0.08 mL provided practically full protection against retinal cell apoptosis 3 days following alkali burn, and infliximab 100 mg only slightly less. At 90 days following burn injury, control optic nerves showed about 50% axon loss as compared to 8% in the adalimumab treatment group.

CONCLUSIONS

Subconjunctival injection of 4.0 mg adalimumab in rabbits shows no eye toxicity and provides excellent neuroprotection, both short (3 days) and long-term (90 days). Our total. accumulated data from several of our studies, combined with the present paper, suggest that corneal injuries, including surgery, might benefit from routine administration of anti-TNF-α biologics to reduce inflammation and future secondary glaucoma.

Glaucoma after penetrating keratoplasty and keratoprosthesis

PURPOSE

To compare visual and glaucoma outcomes in patients with known glaucoma after a penetrating keratoplasty (PKP) or a Boston Keratoprosthesis Type 1 (KPro) as a second corneal replacement procedure.

DESIGN

Retrospective interventional case series.

PARTICIPANTS

Charts of 141 eyes that underwent either a PKP or KPro at the Centre hospitalier de l'Université de Montréal after one failed PKP from 2008 to 2020 were reviewed. Forty-six eyes with preoperative glaucoma were included.

METHODS

Data collected included demographics, indication for the initial surgery, best corrected visual acuity (BCVA), concurrent ocular disorders, number of glaucoma medications, need for glaucoma surgery, cup-to-disc ratios (CDRs), mean RNFL thickness, and visual field (VF) characteristics. Primary outcomes were glaucoma progression trends. Secondary outcomes were visual outcomes and need for additional procedures.

RESULTS

Mean follow-up was 4.7 years for the PKP and 7.3 for the KPro group (P<0.007). 30.6% of PKP compared to 70.5% of KPro patients were diagnosed with glaucoma preoperatively. Glaucoma worsened similarly in both groups; this is based on an analysis of the number of glaucoma medications, CDR, need for glaucoma surgery, and characteristic VF changes. Patients in the PKP group required significantly more regrafts than patients in the KPro group (31.8 vs. 8.3%; P=0.045).

CONCLUSIONS

A preoperative diagnosis of glaucoma does not preclude KPro implantation. In glaucomatous eyes, the disease progressed similarly in both groups. Since both procedures increase the risk of worsening glaucoma, close follow-up is recommended. KPro may decrease the need for further corneal transplantation surgery.

The platelet-rich plasma lysate use in the treatment of persistent epithelial defects after keratoplasty

AIM:to evaluate the effectiveness of the platelet-rich plasma lysate (PRP lysate) use in the treatment of persistent epithelial defects (PED) after keratoplasty. MATERIALS AND METHODS:In the study, 60 patients with PED after keratoplasty were included. The 1st group (24 cases)included patients after keratoplasty with low risk of rejection, and the 2nd group 36 cases after keratoplasty with highrisk of rejection. Each group was divided into two subgroupscontrol subgroups 1a (cases 10) and 2a (cases 16), where patients received only standard postoperative therapy, and the main subgroups 1b (cases 14) and 2b (cases 20), in which PRP lysate was prescribed against the background of standard therapy, starting from the Day 15 post-op. As the criterion for effective treatment, complete persistent epithelialization after keratoplasty was considered. RESULTS:The effectiveness of the use of PRP lysate in the subgroup 1b was 85.7%, while complete epithelialization in the control subgroup 1a was recorded in 70%; in the subgroup 2b, complete epithelialization was observed in 55%, in the control subgroup 2ain 43.75%. CONCLUSION:The use of PRP lysate in the treatment of PED after corneal transplantation as an adjuvant therapy is effective and safe in both high and low risk keratoplasty. In the examined category of patients, treatment with blood derivatives increases the frequency and rate of complete epithelialization.

Risk Factors for the Development of Ocular Hypertension After Keratoplasty: A Systematic Review

Supplemental Digital Content is Available in the Text.

To identify risk factors for the development of ocular hypertension after keratoplasty.

Surgery for glaucoma in modern corneal graft procedures

Glaucoma is a common cause of vision loss after corneal transplantion and is considered a major risk factor for graft failure. Glaucoma may be present before corneal transplant surgery, or increased intraocular pressure may develop after keratoplasty in up to one-third of patients. Pre-existing glaucoma should be controlled before keratoplasty, either medically or surgically. For postkeratoplasty increase in intraocular pressure; identifying the risk factors allows appropiate follow-up and management. Patients undergoing anterior lamellar keratoplasty may take advantage of reduced rates of postkeratoplasty glaucoma. Glaucoma also complicates eyes with endothelial keratoplasties, mostly related to management of intraocular pressure spikes derived from anterior chamber air bubbles. Nevertheless, the severity is less, and the intraocular pressure is more easily controlled when compared with penetrating keratoplasty. Adequate management of glaucoma that develops before or after keratoplasty may save eyes from irreversible damage to the optic nerve and increase graft survival.

Clinical Outcomes of Micropulse Transscleral Cyclophotocoagulation in Patients with a History of Keratoplasty

Purpose

To examine the surgical outcomes and graft conditions in patients receiving micropulse transscleral cyclophotocoagulation (MP-TSCPC) to treat post-keratoplasty ocular hypertension.

Methods

This retrospective observational study included 30 eyes of 28 consecutive glaucoma patients with a history of penetrating keratoplasty (PKP) or Descemet's stripping automated endothelial keratoplasty (DSAEK) who underwent MP-TSCPC at the University of California, San Francisco from 09/2015 to 08/2018. Using the Wilcoxon signed-rank test, we compared preoperative and postoperative intraocular pressure (IOP), number of glaucoma medications, visual acuity, and central corneal thickness at 1, 3, 6, and 12 months. Postoperative complications, additional surgeries, and graft failures were also recorded at these follow-up times. Linear regression model was used to study whether PKP vs. DSAEK affects the effectiveness of MP-TSCPC.

Results

Thirty eyes from 28 patients were followed for 12 months. IOP was significantly decreased from preop at all follow-up points (P < 0.001). There was no significant change in the number of glaucoma drops, visual acuity, or CCT. At 12 months, 21 of the 30 eyes met the definition of success, and only one underwent repeat PKP due to graft rejection. The type of corneal transplant was not a significant factor for IOP reduction at the last follow-up.

Conclusions

MP-TSCPC achieved desirable IOP control and success rates for postkeratoplasty patients while resulting in minimal complications and graft failure. It appears to be a safe and effective procedure in patients who received corneal transplant with one-year follow-up.

Glaucoma after Ocular Surgery or Trauma: The Role of Infiltrating Monocytes and Their Response to Cytokine Inhibitors

Glaucoma is a frequent and devastating long-term complication following ocular trauma, including corneal surgery, open globe injury, chemical burn, and infection. Postevent inflammation and neuroglial remodeling play a key role in subsequent ganglion cell apoptosis and glaucoma. To this end, this study was designed to investigate the amplifying role of monocyte infiltration into the retina. By using three different ocular injury mouse models (corneal suture, penetrating keratoplasty, and globe injury) and monocyte fate mapping techniques, we show that ocular trauma or surgery can cause robust infiltration of bone marrow-derived monocytes into the retina and subsequent neuroinflammation by up-regulation of Tnf, Il1b, and Il6 mRNA within 24 hours. This is accompanied by ganglion cell apoptosis and neurodegeneration. Prompt inhibition of tumor necrosis factor-α or IL-1β markedly suppresses monocyte infiltration and ganglion cell loss. Thus, acute ocular injury (surgical or trauma) can lead to rapid neuroretinal inflammation and subsequent ganglion cell loss, the hallmark of glaucoma. Infiltrating monocytes play a central role in this process, likely amplifying the inflammatory cascade, aiding in the activation of retinal microglia. Prompt administration of cytokine inhibitors after ocular injury prevents this infiltration and ameliorates the damage to the retina-suggesting that it may be used prophylactically for neuroprotection against post-traumatic glaucoma.

Risk of Glaucoma Surgery After Corneal Transplant Surgery in Medicare Patients

PURPOSE

Glaucoma is a well-documented complication of corneal transplants, contributing significantly to ultimate visual loss. Reported incidence of glaucoma following corneal transplants is highly variable, and definitions of posttransplant glaucoma are inconsistent. Here we use glaucoma surgery as a more rigid and specific endpoint to compare rates following different corneal transplant surgeries.

DESIGN

Retrospective cohort study.

METHODS

A 5% random sample of Medicare beneficiaries from 2010-2013 was obtained and patients were identified with Current Procedural Terminology (CPT) codes for penetrating keratoplasty (PK), endothelial keratoplasty (EK), anterior lamellar keratoplasty (ALK), and keratoprosthesis (KPro). Rates of glaucoma surgery within the same year following the abovementioned corneal transplants were analyzed. Subgroup analyses included patients who carried preexisting glaucoma diagnoses prior to corneal transplant surgery.

RESULTS

There were 3098 patients who underwent corneal transplants during the study period, including 1919 EK, 1012 PK, 46 ALK, 32 KPro, and 89 both PK and EK. Rates of glaucoma surgery ranged from 6.1% to 9.4% in the corneal transplant groups, without statistically significant differences among groups. However, 10.0% of patients with preexisting glaucoma required glaucoma surgery following any transplant surgery, compared with 5.3% of patients without preexisting glaucoma. This included 12.4% of PK patients with preexisting glaucoma compared with 2.8% of PK patients without preexisting glaucoma (P < .01).

CONCLUSIONS

Despite literature suggesting that more angle-altering cornea surgeries confer higher risk, we found no statistically significant differences among various transplant groups. Patients with preexisting glaucoma, however, had higher risk of glaucoma surgery within the same year following corneal transplant surgery, which was especially pronounced in the PK group. These patients require special care when considering long-term effects of corneal transplants.

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.

Refractory aqueous misdirection syndrome: A possible complication of penetrating keratoplasty

CLINICAL CASE

An 85 year-old woman presented with a flat anterior chamber of the left eye, severe ocular hypertension, and a normal ultrasound examination in the day following a penetrating keratoplasty (PK). The clinical status did not respond to maximum medical therapy, laser posterior capsulotomy, anterior hyaloidotomy, and complete 23 G vitrectomy. The patient refused further intervention, and light perception was lost after 6 months of follow-up.

DISCUSSION

This is the first report of refractory aqueous misdirection syndrome following primary PK. Despite maximum medical and surgical management efforts, aqueous misdirection syndrome subsequent to primary PK may have a catastrophic outcome.

Boston Keratoprosthesis Type 1 in Chemical Burns

PURPOSE

To describe and further analyze the long-term results in visual acuity (VA), anatomical retention, and rate of complications from patients who underwent Boston keratoprosthesis (B-Kpro) type 1 after ocular chemical burns in the Dominican Republic.

METHODS

A retrospective review of 42 eyes (22 OD:20 OS) of 36 patients who underwent B-Kpro type 1 implantation after severe ocular burn at Hospital Elías Santana in Santo Domingo, Dominican Republic, between April 2006 and October 2014, were included.

RESULTS

Demographics, VA, anatomical retention, and the rates of postoperative complications and concurrent surgeries were evaluated.

CONCLUSIONS

The excellent anatomical retention rates and visual outcomes presented in this study support the remarkable capability of B-Kpro type 1 to restore functional VA in eyes with severe chemical injuries. However, strict control of the postoperative complications is necessary for long-term success. In conclusion, the use of a B-Kpro type 1 after severe chemical burn is a viable option in patients otherwise condemned to the high risk of failure associated with conventional corneal grafts.

Effect of Penetrating Keratoplasty and Keratoprosthesis Implantation on the Posterior Segment of the Eye

PURPOSE

To compare the effects of post-penetrating keratoplasty (PK) and post-keratoprosthesis (KPro) surgery-related inflammation on the posterior segment of the eye and to assess inhibition of tumor necrosis factor alpha (TNFα) and interleukin-1 beta (IL-1β) on these effects.

METHODS

BALB/C (syngeneic) or C57BL/6 (allogeneic) corneas were transplanted onto BALB/C host beds as part of PK or miniature KPro (m-KPro) implantation. Intraocular pressure (IOP) was measured via an intracameral pressure sensor; tissues were harvested and analyzed 8 weeks after surgery. Expression of TNFα and IL-1β in the retina was analyzed using real-time quantitative (q)PCR. Optic nerve degeneration (axon count, circularity, and area) was assessed quantitatively using ImageJ software. After m-KPro implantation, mice were treated with saline, anti-TNFα, or anti-IL-1β antibody, and axonal loss was assessed after 10 weeks.

RESULTS

Mean IOP was within normal limits in the operated and fellow eyes in all groups. The mRNA expression of TNFα and IL-1β was highest in m-KPro groups with either syngeneic or an allogeneic carrier. We observed optic nerve degeneration in both allogeneic PK and m-KPro implanted eyes with an allogeneic carrier. However, TNFα blockade significantly reduced axonal loss by 35%.

CONCLUSIONS

Allogeneic PK and m-KPro implants with an allogeneic carrier lead to chronic inflammation in the posterior segment of the eye, resulting in optic nerve degeneration. In addition, blockade of TNFα prevents axonal degeneration in this preclinical model of allogeneic m-KPro (alloKPro) implantation.

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.

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.

Current concepts in the treatment of vitreous block, also known as aqueous misdirection

Vitreous block (VB), a rare secondary angle-closure caused by anterior rotation of the ciliary body, occurs in a variety of settings, but most frequently after glaucoma filtering surgery. The etiology remains unclear, but choroidal expansion and anterior vitreous abnormalities have been proposed. In the past, treatment of VB has yielded high rates of failure and recurrence. Advancements in surgical techniques, however, have led to improved visual outcomes. We review the history of this condition and present a stepwise approach to its diagnosis and treatment using modern imaging modalities and surgical techniques.

Long-term changes in corneal endothelial cell density after repeat penetrating keratoplasty in eyes with endothelial decompensation

PURPOSE

To compare the longitudinal changes in corneal endothelial cell density (ECD) and the incidence of postoperative complications between eyes with endothelial decompensation after repeat penetrating keratoplasty (RPK) and those after primary penetrating keratoplasty (PPK).

METHODS

Fifty-seven eyes with endothelial decompensation scheduled for RPK (RPK group) and 57 eyes with endothelial decompensation scheduled for PPK (PPK group) were enrolled. Corneal ECD was evaluated using a specular microscope at 1, 3, 6, 9, and 12 months, and every 6 months until 60 months postoperatively. Visual acuity (VA) and incidence of graft failure, graft rejection, or marked increase in intraocular pressure were examined.

RESULTS

Corneal ECD decreased gradually and percentage of cell loss at 60 months was approximately 73% in both groups; these did not differ significantly between groups throughout the follow-up (P ≥ 0.2209). The incidence of graft failure (52.6% in the RPK group and 36.8% in the PPK group), immune rejection, and marked increase in intraocular pressure did not differ significantly between groups (P ≥ 0.0898), although corrected VA was worse in the RPK group. The most common cause of graft failure in both groups was late endothelial failure. The outcomes were not significantly different between eyes that underwent a first RPK and those that underwent a second or subsequent RPK.

CONCLUSIONS

Corneal endothelial cell loss and complications are comparable between eyes with endothelial decompensation after RPK and those after PPK, although VA is worse in eyes after RPK. The outcomes after a first RPK did not differ from those after multiple RPKs.

Shunts to divert aqueous humor to distant epithelialized cavities after keratoprosthesis surgery

PURPOSE

Glaucoma is a frequent and often severe problem in patients needing keratoprosthesis (KPro) surgery. Standard glaucoma shunts in these cases often develop a very dense capsule that obstructs flow and causes intraocular pressure elevation. Therefore, we developed shunts that deliver aqueous to distant epithelialized cavities where an obstructing capsule is less likely to form. In this retroactive study of such shunts, the risk of postoperative infection (especially endophthalmitis) has been assessed.

METHODS

Ahmed shunts were connected with a tube to the lacrimal sac or ethmoid sinuses. In subsequent designs the polypropylene plate was eliminated, the valve was enclosed and a distal tube added (New World Medical Inc, Rancho Cucamonga, CA). The latter shunts were connected to the maxillary sinus or lower lid fornix. Between 2001 and 2005 the devices were implanted in 34 patients with very severe ocular disease. (31 had KPro implanted). Thus, the distal tube was led to the lacrimal sac (2 cases), to the ethmoid sinuses (6), to the maxillary sinus (16 cases), and to the lower lid fornix (10 cases). The patients were followed for cumulatively 145 shunt years, with a mean follow-up of 4 years and 3 months. They were instructed to administer low-dose topical antibiotics indefinitely.

RESULTS

Only 1 case of acute bacterial endophthalmitis occurred, thus an incidence of 0.7% per shunt year. A slow-growing Mycobacterium was cultured in a disintegrating eye and 1 bacterial maxillary sinusitis occurred, both in autoimmune diseases. Three valves became exposed and had to be removed (1 replaced). Four eyes developed hypotony, probably from valve failure.

CONCLUSIONS

The shunt arrangement, which connects the anterior chamber to potentially microbe-populated cavities or to the lower lid fornix and its flora, might be suspected to allow rapid retrograde invasion of infective agents, resulting in endophthalmitis. In this series of KPro patients, however, the incidence of severe infection was very low, in fact comparable to that after standard trabeculectomy.

Incidence and prevalence of glaucoma in severe ocular surface disease

PURPOSE

To describe the incidence and prevalence of glaucoma in a patient population with severe ocular surface disease (OSD).

METHODS

A retrospective case series was compiled from all charts of patients in the Cincinnati Eye Institute/University of Cincinnati and University of Minnesota population with a diagnosis of severe OSD from 1991 to 2003. The incidence and prevalence of glaucoma in the overall patient population were identified, and stratified into disease subgroups.

RESULTS

Of the 108 eyes evaluated in this study, 71 were diagnosed with glaucoma. The overall prevalence of glaucoma in patients with severe OSD is 65.7%, with a range from 42.9% to 88.4%. Analysis by subgroup shows the highest percentage of patients with concurrent glaucoma fall into the categories of aniridia and chemical injury, and the lowest was noted in those patients with autoimmune or iatrogenic OSD. Overall, the incidence of glaucoma was 20.4%, with a range of 13.6% to 60%.

CONCLUSIONS

Compared with previous studies, our results show a significantly higher prevalence of glaucoma in patients with severe OSD. This information warrants increased attention to treatment and management of OSD and concurrent glaucoma.

Automated superficial lamellar keratectomy augmented by excimer laser masked PTK in the management of severe superficial corneal opacities

AIM

To assess superficial lamellar keratectomy augmented by excimer laser smoothening with sodium hyaluronate 0.25%, for the management of superficial corneal opacities.

METHODS

Consecutive procedure performed in 14 eyes (13 patients) with an automated microkeratome and excimer laser phototherapeutic keratectomy (PTK) smoothening using sodium hyaluronate 0.25%.

MAIN OUTCOME MEASURES

UCVA, BCVA, pachymetry, degree of haze, ray tracing analysis, and complications. Mean follow up was 12 (SD 1.6) months.

RESULTS

Mean preoperative haze from previous corneal refractive surgeries was 3.5 (SD 0.5) (11/14 cases). In one case, opacity was caused by ocular trauma and in two by infectious keratitis. The mean preoperative UCVA was 0.7 logMAR (0.2 (SD 0.13) decimal value). BCVA was 0.4 logMAR (0.4 (SD 0.17) decimal value). Mean preoperative corneal pachymetry was 508 (SD 62.5) micro m and mean opacity depth measured by corneal confocal microscopy was 115.2 (SD 49.4) micro m. At 6 months, 71.4% of the eyes with previous corneal refractive surgery showed grade I haze or less. Mean postoperative corneal pachymetry at 6 months was 352.36 (SD 49.05) micro m.

CONCLUSIONS

Automated superficial lamellar keratectomy combined with excimer laser PTK smoothening assisted by sodium hyaluronate 0.25% induces a significant improvement of corneal transparency and visual acuity in cases of corneal opacity caused by previous refractive surgery, ocular trauma, and keratitis.

Development and progression of cataract in patients required repeated corneal transplantation

PURPOSE

To evaluate the incidence of cataract development in patients required repeated corneal transplantations, the types of cataract and the effect of cataract extraction on the corneal regrafts survival.

PATIENTS AND METHODS

The charts of all the patients that underwent repeated corneal transplantation between 1985 and 1998 were reviewed for the development of cataract after the first or subsequent keratoplasties. In all, 80 patients underwent 122 repeated corneal transplantations, of which six underwent surgery in both eyes. The average follow-up period of all the patients with repeated keratoplasty was 89.5 months from the first keratoplasty.

RESULTS

Of 86 eyes 19 (22%) that underwent repeated keratoplasties developed cataract. The cataract developed between 1 month and 17 years (average 61.3 months) after the first transplantation. The incidence of cataract development was independent of the number of repeated keratoplasties. In certain patients, such as patients with acute and severe regraft immune rejection, the cataract progressed more rapidly. Despite different cataract extraction procedures, the grafts in 17 eyes of the 19 (89.5%) failed following cataract surgery and 16 of them underwent additional corneal regrafting. The regrafts in eight of the 16 regrafted eyes (50%) remained clear with improvement in visual acuity. At the end of the follow-up, 10 eyes of the 19 had clear regraft (53%) comparable with the rate of clear grafts in the entire regrafted group (51%, P=NS).

CONCLUSION

Corneal transplantation may be a trigger for slow development of cataract over years but repeated keratoplasties did not increase the risk for cataract development. Although failure of regrafts may occur after cataract extraction, subsequent corneal transplantation has a comparable survival and visual outcome with the entire regrafted group.