Intraoperative Application Of Mitomycin Research Articles

Comparative Assessment of Mitomycin C versus Limbal Conjunctival Autograft for Primary Pterygium Removal: An Evaluation of Efficacy

Objective: This study aims to evaluate and contrast the outcomes achieved by application of mitomycin C 0.02% intra-operatively versus employing limbal conjunctival autograft after the removal of primary pterygium. Study Design: Randomized controlled trial (RCT) Place and duration: The research was carried out at the Ophthalmology Department of Ghazi Hospital in Dera Ghazi Khan, spanning from October 2021 to September 2022. Methodology: The research included 62 participants who were divided into two groups; one group receiving Mitomycin C and the other group underwent limbal conjunctival autograft. The main variables assessed in the study were the laterality of pterygium, size of pterygium extending over the limbus, preoperative and postoperative best corrected visual acuity, and the rate of pterygium recurrence in both groups. The analysis of data was conducted utilizing SPSS version 24. Results: In Group MMC, 48.4% of patients showed right laterality, while in Group LCAU, 58.1% (p=0.445) showed it. The average size of pterygium crossing the limbus, as well as preoperative and postoperative best corrected visual acuity, were similar between both groups (p>0.050). Regarding recurrences, the percentages at 3, 6, and 9 months, as well as after 1 year, were higher in Group MMC (12.9%, 6.5%, 16.1%, 9.7%, 45.2%) compared to Group LCAU (9.7%, 9.7%, 3.2%, 6.5%, 29%), but these differences were not statistically significant (p=0.526). Conclusion: Limbal conjunctival autograft appears to be more effective in preventing recurrence following the excision of primary pterygium compared to intraoperative application of Mitomycin C. However, both techniques, whether simple excision with LCAU or MMC application, demonstrate acceptable outcomes with only minor differences in recurrence rates. Surgeon expertise and preferences in local practice play significant roles as main risk factors influencing the choice between these two methods.

A Degradable Sustained-Release Drug Delivery System for Bleb-Forming Glaucoma surgery.

Fibrosis of the filtering bleb is one of the main causes of failure after bleb-forming glaucoma surgery. Intraoperative application of mitomycin C (MMC) is the current gold standard to reduce the fibrotic response. However, MMC is cytotoxic and one-time application is often insufficient. A sustained-release drug delivery system (DDS), loaded with MMC, might be less cytotoxic and equally or more effective. Two degradable (polycaprolactone (PCL) and polylactic-co-glycolic acid (PLGA)) MMC-loaded DDSs were developed. Release kinetics were first assessed in vitro followed by rabbit implants in conjunction with the PRESERFLO® MicroShunt. As a control, the MicroShunt was implanted with adjunctive use of a MMC solution. Rabbits were euthanized at postoperative day (POD) 28 and 90. The PLGA and PCL DDSs released (on average) 99% and 75% of MMC, respectively. All groups showed functioning blebs until POD 90. Rabbits implanted with a DDS showed more inflammation with avascular thin-walled blebs when compared to the control. However, collagen was more loosely arranged. The PLGA DDS showed less inflammation, less foreign body response (FBR) and more complete degradation at POD 90 when compared to the PCL DDS. Further optimization with regard to dosage is required to reduce side effects to the conjunctiva. This article is protected by copyright. All rights reserved.

Cessation of Recurrent Bilateral Optic Disc Haemorrhages after Successful Trabeculectomy: A Case Report

Purpose: To describe a patient with primary open-angle glaucoma in whom bilateral recurrent optic disc haemorrhages disappeared permanently after trabeculectomy. Methods: A 67-old male patient was diagnosed with primary open-angle glaucoma and was followed for 10 years including best corrected visual acuity, visual field examinations, slit lamp examinations, Goldmann applanation tonometry, fundoscopy and optic disc photographs. Results: Optic disc haemorrhages were detected in 8 out of 30 preoperative visits in the right eye and in 3 out of 19 visits in the left eye. Trabeculectomy with intraoperative application of mitomycin C was performed in both eyes due to the advanced visual field loss with an inadequate intraocular pressure control despite maximum-tolerated medical therapy and because of the recurrent optic disc haemorrhages. No further optic disc haemorrhages were observed in either eye after trabeculectomy. Conclusion: Our case report demonstrates that recurrent bilateral optic disc haemorrhages can cease permanently after successful trabeculectomy.

Efficacy and Safety of the Intraoperative Application of Mitomycin in Glaucoma Patients with Trabeculectomy: A Systematic Review and Meta-Analysis

What Is Known and Objective. The primary cause of trabeculectomy failure in glaucoma surgery is the imperfect formation of the filter bubble, which blocks the filtration effect. This systematic review and meta-analysis aimed to compare the effects and safety of mitomycin C (MMC) or no antimetabolite in trabeculectomies cases that require needling revision. Methods. We searched PubMed, Cochrane, and EMBASE to identify randomized trials published between the time the databases were built and May 31, 2022. To compare the effectiveness and safety of mitomycin with or without mitomycin in trabeculectomy, intraocular pressure (IOP), the surgical failure rate, and functional follicle formation were used as efficacy indicators, and the occurrence of postoperative complications was used as a safety indicator. Meta-analyses were performed for comparisons. Results and Discussion. After trabeculectomy, MMC was significantly better than a placebo at lowering postoperative IOP (MD = −11.31 mmHg, 95% CI −19.73 to −2.88 mmHg). MMC outperformed the control group in terms of filtering blebs formation (relative risk (RR) = 1.18, 95% CI: 1.09 to 1.27). The surgical failure rate was significantly lower with MMC compared to placebo (RR = 0.35, 95% CI: 0.22 to 0.58). No significant difference was observed between MMC and placebo in terms of hypotony, anterior chamber bleeding, filter bubble leakage, and endophthalmitis, apart from the shallow anterior chamber (RR: 1.51, 95% CI: 1.02 to 2.25). What Is New and Conclusion. The use of MMC in glaucoma trabeculectomy can increase the success rate of the procedure and provide significant patient benefits. However, it is important to be extremely careful and aware of complications such as shallow anterior chambers.

Effects of Preoperative Versus Intraoperative Application of Mitomycin C on the Outcome of Pterygium Surgery: A Meta-Analysis

Background: The use of mitomycin C (MMC) has been recommended to reduce postoperative recurrence in patients undergoing pterygium surgery. However, the outcomes with preoperative (PO) and intraoperative (IO) application of mitomycin C have not been adequately compared. Objective: This study aimed to evaluate PO MMC versus IO MMC in terms of recurrence and complications for pterygium treatment. Methods: PubMed, EMBASE, and Cochrane Library were systematically searched with the keywords “pterygium,” “mitomycin,” and “preoperative” and “intraoperative.” Randomized controlled trials (RCTs) comparing PO MMC with IO MMC in pterygium surgery were included. A risk of bias tool was used to perform qualitative assessments. Outcome measurements were recurrence and complications of the ocular surface. Review Manager 5.3 was used for statistical analysis. Results: Five RCTs with 390 participants (390 eyes) showing primary or recurrent pterygium were included. Recurrence of pterygium with PO MMC was similar to that with IO MMC (RR = 1.04, 95% CI, 0.61 to 1.76, P = 0.89). There was no significant difference between the two treatments (PO MMC vs. IO MMC) with respect to complications of the ocular surface, including conjunctival complications (RR = 1.04; 95% CI, 0.61 to 1.76; P = 0.89), scleral complications (RR = 0.72; 95% CI, 0.14 to 3.73; P = 0.70), and corneal complications (RR = 1.33; 95% CI, 0.32 to 5.48; P = 0.70). Conclusion: PO MMC was as efficient as IO MMC in controlling the recurrence and complications in pterygium surgery.

Sturge-Weber syndrome coexisting with polydactyly: a case report

BackgroundSturge-Weber syndrome (SWS) is a sporadic congenital disorder, characterized by unilateral facial nevus flammeus associated with ipsilateral glaucoma, choroidal angioma and leptomeningeal hemangiomas. SWS can comorbid with other disorders in some patients, however, there has been no prior described case of SWS and polydactyly occurring in the same patient.Case presentationA 15-year-old girl with diagnosis of SWS presented to our hospital. She had bilateral glaucoma and extensive port-wine stains distributing in bilateral faces, left neck and left upper limb. Meanwhile, the patient was noted to demonstrate the superfluous digit attaching on the left thumb and was diagnosed as polydactyly. Trabeculectomy, with intraoperative application of mitomycin C and postoperative subconjunctival injections of 5-fluorouracil, was successful in controlling the intraocular pressure in both eyes.ConclusionsWe report a case with bilateral SWS coexisting with unilateral polydactyly, which, to our knowledge, has not been recognized previously and adds further evidence to the existing literature. In view of the rare concurrence of SWS and polydactyly, the etiology is unclear and further investigation is required to explore the underlying pathogenesis.

Recurrence and Complication Rates among Current Pterygium Treatment Techniques: Pre-operative Subpterygeal Mitomycin-C Injection, Intraoperative Mitomycin C Application and Pterygium Excision with Conjunctival Autograft

Objective. This study aims to determine recurrence and complication rates among patients who underwent threecurrent pterygium treatment techniques: preoperative subpterygeal injection of mitomycin C, intraoperativeapplication of mitomycin with pterygium excision and pterygium excision with conjunctival autograft.
 Methods. This is a randomized controlled clinical trial in a tertiary hospital. We included patients with diagnosedprimary pterygium and who underwent either: A = pre-operative injection of 0.02% mitomycin C one month prior topterygium excision; B = pterygium excision with intraoperative mitomycin C application; or C = pterygium excisionwith conjunctival autograft.
 Results. We included 111 patients: a total of 120 eyes randomized to 3 groups (A, B, C) at 40 eyes per group.After 24 months of follow-up, there was no significant difference in the recurrence rates among the groups (6/40[15%] in groups A and B and 2/40 cases [5%] in group C; P=0.29). No complications were noted in groups B and C,while 1 case of scleral thinning was noted in group A. There was no significant difference in the complication ratesamong the three procedures (P=1.00).
 Conclusion. There were no significant differences in the recurrence and complication rates among the three techniques. Careful patient selection and follow-up are recommended to prevent complications such as scleral thinning.

Injected Versus Sponge-Applied Mitomycin C (MMC) During Modified Trabeculectomy in New Zealand White Rabbit Model.

PurposeMitomycin C is routinely applied during trabeculectomy surgeries to enhance bleb survival after glaucoma filtration surgery. The current approach involves placing cellulose sponges soaked in mitomycin C at a standard concentration onto bare sclera for a predetermined duration, which varies among surgeons. The purpose of this study was to compare the effects of sponge-applied versus intra-Tenon injection of mitomycin C during modified trabeculectomy.MethodsTwo groups of five New Zealand White rabbits underwent glaucoma filtration surgery with either preoperative intra-Tenon injection of mitomycin C or intraoperative application of mitomycin C using a cellulose sponge. Postoperative intraocular pressure was recorded weekly, and eyes were enucleated and sent for pathological examination and histological analysis.ResultsAn intra-Tenon injection of mitomycin C resulted in decreased intraocular pressure measurements and bleb vascularity compared to the controls but increased levels compared to the sponge-applied group. Collagen deposition and cellularity were reduced and the goblet cell population was increased in the intra-Tenon injection group.ConclusionsThis study shows that an intra-Tenon injection can be an effective method for administering mitomycin C compared to the standard-of-care approach of mitomycin C being sponge applied onto bare sclera. Mitomycin C injection led to a greater reduction in intraocular pressure and inhibition of fibroblasts. The associated goblet cell population that can lead to increased mitomycin C toxicity-related morbidity was minimized with the intra-Tenon injection compared to the sponge-applied MMC treatment. Therefore, patients with ocular surface disease may benefit from an intra-Tenon injection.Translational RelevanceThis project provides a direct, qualitative assessment in an animal model of common techniques within glaucoma filtration surgery for drug delivery to improve surgical success.

Necrotizing scleritis after “pterygium” excision with mitomycin C

AbstractPurposeApplication of Miitomycin C during pterygium excision is discussed to reduce its recurrence rate. Nevertheless, potential adverse effects of Mitomycin C application should be evaluated in each individual patient.MethodWe report on minimal invasive procedures applied in a case of scleral necrosis following pterygium excision combined with intraoperative application of Mitomycin C. A 87‐year old man presented for a second opinion having suffered a severe ocular pain on the left eye for the last three weeks after pterygium surgery. At presentation, a gradual thinning of the sclera spreading to the adjoining cornea was observed. In addition, signs of chronic blepharitis with a dysfunction of the marginal eyelid glands, as well as, a negative Bell’s sign were observed on both eyes.ResultsLocal lubrication was applied, supported by broad‐spectrum local antibiotic therapy. In order to prevent perforation and strengthen the corneal stroma, doxycycline 100 mg daily, was added. The initiated systemic prednisone treatment was reduced to 20 mg daily. In addition, to support sufficient eyelids closure in the presence of negative Bell’s phenomenon, 20 units Botox was applied. Within the following days a gradual remission was achieved; with reduction of necrotic area and perilimbal ischemia, supporting thus, the corneal thickening and consequently the symptomatic pain release. Furthermore, histological results of the excised pterygium revealed conjunctival tissue with focal metaplasia of the squamous epithelium, stromal fibrosis, elastosis, and a small amount of conjunctival calcification, findings compatible with pinguecula on atypical location.ConclusionThe presented case confirms that application of mitomycin C should be used with consideration in patients featuring pre‐existing trophic anterior segment disease and/or systemic disease predisposing to wound‐healing impairment.

Safety and complications after three different surface ablation techniques with mitomycin C: a retrospective analysis of 2757 eyes.

To evaluate the safety and spectrum of complications of three excimer laser surface ablation techniques (SATs) with an intraoperative application of mitomycin C (MMC) 0.02%. A retrospective, non-comparative large case series. SATs were performed on 2757 eyes with a preoperative spherical equivalent (SE) of - 4.41 ± 2.44 and a Wavelight Allegretto 200 platform. Ablation zone diameters between 6.0 and 7.0mm were used according to mesopic pupil size. All patients were treated with an intraoperative application of MMC for 30 to 90s depending on refractive error. The mean follow-up time was > 3months (107 ± 24days). Complication range and incidence were analyzed retrospectively and safety index was calculated. Two thousand seven hundred and fifty-seven eyes met the inclusion criteria for surface ablation. Two thousand five hundred and seventy-three eyes were assigned to alcohol-assisted photorefractive keratectomy (APRK), 135 eyes to transepithelial photorefractive keratectomy (TPRK), and 49 eyes to off-flap epithelial laser in situ keratomileusis (EpiLASIK/EpiK). Overall, the safety index was 1.06 ± 0.28. Haze was graded according to the Fantes scale. Haze incidence rates were highest in the TPRK group (14.81%) and comparably low in APRK (2.95%) and EpiK (4.08%) groups. Intraoperative topical application of MMC (0.02%) results in good safety and no severe side effects. However, highest incidence of haze was observed after TPRK. The more frequent peripheral localization of haze might be attributed to large ablation zones and the wavefront optimized ablation profile especially in the PTK modus of the laser platform.

Bleb-related infections and long-term follow-up after trabeculectomy.

Bleb-related infections are serious complications after trabeculectomy. They can be limited to the bleb or disseminate and lead to endophthalmitis. We herein report on all bleb-related infections that have been diagnosed at the Eye Center of the University of Freiburg, Germany, since 1999. We reviewed a total of 1816 consecutive trabeculectomies that were performed at our hospital between the years 1999 and 2014 (353 without and 1463 with intraoperative application of mitomycin C). All bleb-related infections that were diagnosed at our clinic during the same period were included in the analysis. We fitted a Cox proportional hazards model to characterize risk factors for bleb-related infections. We diagnosed a total of 19 bleb-related infections in this period. Three patients with bleb-related infections that came to our clinic had their trabeculectomy performed elsewhere. The overall percentage of bleb-related infections was 0.1% after 2years (Kaplan-Meier estimate at median follow-up). Nine eyes suffered from only localized infection of the bleb. Seven eyes developed endophthalmitis. Four infections occurred during the first postoperative month. The median age on the day of diagnosis was 71years; the median age at surgery was 69years. In the Cox model, intraoperative application of mitomycin C and a fornix-based conjunctival flap were identified as significant risk factors (hazard ratio: 79.02, 4.69; p<0.01, p<0.01). The whole group showed a reduction of visual acuity in the median from logMAR 0.12 to 0.2. Eyes that suffered from endophthalmitis showed a loss from 0.3 to 0.96, while the localized infections had a reduction from 0.04 to 0.07. Bleb-related infections are a rare complication following trabeculectomy and can be localized on the bleb or can lead to endophthalmitis, thereby threatening visual acuity. The risks and benefits of mitomycin C-augmented trabeculectomies should be taken into consideration.

The astigmatic effect of pterygium in a Tertiary Hospital in Kano, Nigeria.

Aim:This study aims to determine the effect of pterygium excision on the degree of corneal induced astigmatism and visual acuity.Patients and Methods:This was a prospective interventional study conducted between September 2012 and June 2013. Consecutive patients with pterygium who met the inclusion criteria were recruited into the study. They had a basic eye examination, and those with existing comorbidity were excluded. Selected patients had pterygium excision using the bare sclera technique with intraoperative application of Mitomycin C. Detailed pre- and post-operative evaluation and refraction was done.Results:There were 45 eyes of 33 patients aged 28–75 years. The mean age was 56.12 + 12.38 years. Six eyes had Grade I, 29 eyes had Grade II and 10 eyes had Grade III pterygium. The mean value for preoperative astigmatism was 2.12 ± 1.09 diopter cylinder (DC) while that for postoperative astigmatism was 0.72 ± 0.50 DC (P = 0.000). Surgery was associated with statistically significant increase in postoperative visual acuity. (P = 0.000).Conclusion:This study has shown that the degree of pterygium-induced astigmatism reduces significantly following surgical excision. Pterygium excision was associated with improvement in visual acuity.

Enhancement After Myopic Small Incision Lenticule Extraction (SMILE) Using Surface Ablation

To report the feasibility and outcomes of surface ablation after small incision lenticule extraction (SMILE). In this retrospective evaluation of 1,963 SMILE procedures, 43 eyes (2.2%) were re-treated at three separate clinics. Of these, 40 eyes of 28 patients with a follow-up of at least 3 months were included in the analysis. During surface ablation, mitomycin C was applied for haze prevention. Spherical equivalent was -6.35 ± 1.31 diopters (D) before SMILE and -0.86 ± 0.43 D before surface ablation. Surface ablation was performed after a mean of 9.82 ± 5.27 months and resulted in a spherical equivalent of 0.03 ± 0.57 D at 3 months (P < .0001). The number of patients within ±0.50 and ±1.00 D of target refraction increased from 22.5% to 80% and from 72.5% to 92.5%, respectively. Mean uncorrected distance visual acuity (UDVA) improved from 0.23 ± 0.20 to 0.08 ± 0.15 logMAR (P < .0001); 65% of patients gained at least one line. Corrected distance visual acuity (CDVA) remained unchanged with 0.01 ± 0.07 logMAR before versus -0.01 ± 0.05 logMAR after re-treatment (P = .99). Six eyes (15.0%) lost one line of CDVA, but final CDVA was 0.00 logMAR in four and 0.10 logMAR in two of these cases. The safety and efficacy indices were 1.06 and 0.90 at 3 months, respectively. Three of the four surface ablation profiles (Triple-A, tissue-saving algorithm, and topography-guided) resulted in equally good results, whereas enhancement with the aspherically optimized profile (ASA), used in two eyes, resulted in overcorrection (+1.38 and +1.75 D). Combined with the intraoperative application of mitomycin C, surface ablation seems to be a safe and effective method of secondary enhancement after SMILE. Due to the usually low residual myopia, the ASA profile is not recommended in these cases. [J Refract Surg. 2017;33(8):513-518.].

Limbal conjunctival versus amniotic membrane in the intraoperative application of mitomycin C for recurrent pterygium: a randomized controlled trial.

This study compared the outcomes of a limbal conjunctival autograft (LCAG) with those of an amniotic membrane graft (AMG) followed by intraoperative 0.02% mitomycin C (MMC) to treat recurrent pterygium. In this randomized controlled trial, ninety-six eyes with recurrent pterygium were enrolled and randomly allocated into two groups using a computer-generated random number table. Pterygium removal was followed by intraoperative 0.02% MMC for 3min and then either LCAG or AMG transplantation. The major outcomes were recurrence rate, conjunctival inflammation grade, healing time of the corneal epithelial defect, eye-movement amplitude (EMA), uncorrected distance visual acuity (UDVA), and complications. A follow-up of 12months was conducted for 93 eyes of 82 patients. Grade D (recurrence) presented in one eye of the LCAG group and five eyes of the AMG group, with no between-group difference (p = 0.196). However, Grades A, B, and C presented in 46, zero and zero eyes of the LCAG group respectively, and in 37, two and two eyes of the AMG group respectively, with the surgical bed generally showing a better appearance in the LCAG group than in the AMG group (p = 0.008). Compared with baseline values, the postoperative EMA improved significantly in both groups (p < 0.001 for the LCAG group; p = 0.001 for the AMG group), as did UDVA (p = 0.005 for the LCAG group; p = 0.012 for the AMG group). No between-group differences were found in terms of the healing time for epithelial defect, conjunctival inflammation grade, or the frequency of complications such as punctate epithelial keratitis, episcleral melting, corneal pannus, and delayed corneal epithelium healing. LCAG transplantation with intraoperative 0.02% MMC is as efficacious in treating recurrent pterygium as AMG transplantation with MMC. The former procedure results in an attractive cosmetic appearance but might result in limbal damage in some eyes. The surgeon's familiarity with these procedures should determine the method of treatment.

Inhibitory effects of bevacizumab on filtering bleb scarring following trabeculectomy in rabbits

Background The primary reason to trabeculectomy failure is fibrosis of conjunctiva and episclera because of progressive fibroblast proliferation and collagen deposition of the filtration bleb.Conventional methods of inhibiting bleb scarring was intraoperative application of mitomycin C (MMC), but many complications occured after surgery.Researches showed that bevacizumab was an antifibrotic agent, and whether it can suppress scarring of filtering bleb after trabeculectomy is concerned. Objective The aim of this study was to evaluate the antifibrotic efficacy of bevacizumab after trabeculectomy in rabbits. Methods Forty New Zealand rabbits were randomly divided into four groups.Trabeculectomy was performed on the right eyes of each rabbits.The rabbits received subconjunctival injection of 0.05 ml bevacizumab (25 mg/ml) at the end of operation in the bevacizumab single injection group.The same dose of bevacizumab was respectively injected at the end of operation as well as 3 days and 7 days after operation in the bevacizumab repitition injection group, and 0.05 ml normal saline solution was used in the same way in the normal saline group.In the MMC group, MMC cotton patch with 0.2 mg/ml was placed under the Tenon caplsule and scleral flap for 3 minutes during operation.The intraocular pressure (IOP), bleb area and shape were evaluated during the 28-day period.The animals were sacrificed on postoperative day 14 and 28, respectively for the histopathologic examination of bleb.The expression of CD31 in the bleb was detected by immunohistochemistry for the calculation of microvessels.All experiments were performed in accordance with the ethics code for animal experimentation and approved by the Institutional Review Board of Tianjin Eye Hospital. Results No significant difference was found in the postoperative IOP among the groups (F=0.88, P=0.47). Compared with the bevacizumab single injection group, MMC group and normal saline group, the shape of bleb was higher and much diffuse with sparse vessels 7 days after operation in the bevacizumab repitition injection group.The survival time of bleb was 27 days, 19 days and 13 days in the bevacizumab repitition injection group, the bevacizumab single injection group, MMC group and normal saline group, respectively.The percentage of collagen deposition area was (49.18±1.54)%, (26.41±1.23)%, (50.68±1.87)% and (70.63±1.81)% at day 14 postoperative in the bevacizumab single injection group, bevacizumab repitition injection group, MMC group and normal saline group, respectively, with the largest area in the normal saline group, and percentage of collagen deposition area was significantly reduced in the bevacizumab repitition injection group compared with the bevacizumab single injection group (all at P<0.05). The percentage of collagen deposition area was (66.82±1.53)% at day 28 postoperative in the bevacizumab repitition injection group, while complete scarring was seen in other 3 groups.The number of microvessels was least at postoperative day 14 in the bevacizumab repitition injection group compared with the bevacizumab single injection group, MMC group and normal saline group (all at P<0.05). The number of microvessels was more in postoperative day 28 in the bevacizumab repitition injection group (3.51±0.31) compared with other groups (all at P<0.05). Conclusions Subconjunctival injection of bevacizumab following trabeculectomy can improve the successful rate of surgery by remaining the survival time of filtering bleb, inhibiting the bleb scarring in rabbits. Key words: Antibodies, monoclonal, humanized; Bevacizumab; Conjunctiva/pathology; Disease models, animal; Fibrosis/prevention c Glaucoma/surgery; Trabeculectomy; Wound healing/drug effects

Corneal Regeneration After Photorefractive Keratectomy: A Review

Photorefractive keratectomy (PRK) remodels corneal stroma to compensate refractive errors. The removal of epithelium and the ablation of stroma provoke the disruption of corneal nerves and a release of several peptides from tears, epithelium, stroma and nerves. A myriad of cytokines, growth factors, and matrix metalloproteases participate in the process of corneal wound healing. Their balance will determine if reepithelization and stromal remodeling are appropriate. The final aim is to achieve corneal transparency for restoring corneal function, and a proper visual quality. Therefore, wound-healing response is critical for a successful refractive surgery. Our goal is to provide an overview into how corneal wounding develops following PRK. We will also review the influence of intraoperative application of mitomycin C, bandage contact lenses, anti-inflammatory and other drugs in preventing corneal haze and post-PRK pain.

Sealing the gap between conjunctiva and Tenon’s capsule in primary pterygium surgery

Objetive: To assess the results of an alternative surgical approach in the excision of primary pterygium by analyzing the rates of recurrence and of intraoperative and postoperative complications. Methods: Retrospective cross-sectional study based reviewing the clinical records of individuals subjected to surgery for pterygium, with conjunctival autograft transplantation, fibrin glue and intraoperative application of mitomycin C. In addition, sealing was performed by suturing the gap between the conjunctiva and Tenon’s capsule. A total of 36 eyes from 35 individuals were subjected to the assessed techniques. The study variables were complications of surgery and recurrence rates during a minimun follow-up period of 6 months. Results: No recurrence occurred during the follow-up period. One graft (2.8%) exhibited partial retraction, but pterygium did not recur. The intraocular pressure increased in one eye (2.8%) and was controlled by clinical methods. Conclusion: Eyes in which a barrier was established between the conjunctiva and Tenon’s capsule by sealing the gap between them showed an absence of recurrence in the sample studied. However, there is the need of a random prospective study with a control group for a more accurate conclusion on the efficacy of the technique

The outcome of preoperative subconjunctival bevacizumab injection in pterygium surgery

ObjectiveThe aim of this study was to evaluate the safety and the efficacy of subconjunctival injection of bevacizumab (Avastin) for the management of primary and recurrent pterygia and to estimate the recurrent rate of pterygia after surgery.Patients and methodsThe study included 60 eyes of 60 patients (45 male and 15 female), with a mean age of 41 ± 4.8 years. Forty patients (66.6%) had primary pterygia and the remaining 20 patients had recurrent pterygia after a previous surgery. A preoperative injection of bevacizumab was given at a dose of 1.25 mg (0.05 ml) 1 week before pterygium surgery was performed using the conjunctival flap technique. Twenty patients were enrolled as a control group and they were operated upon without preoperative bevacizumab injection. Mitomycin C (0.1 mg/ml) was used intraoperatively in recurrent cases. All patients were followed up for 3-6 months.ResultsMost of the patients (48.3%) had grade 2 pterygium. The average time for each procedure was 30 ± 15 min. No patient lost vision after the procedure. Recurrence was noted in five patients (8.3%), and all of them had primary pterygia. Conjunctival graft rejection occurred in three patients (5%); this graft rejection occurred in recurrent pterygia. Postoperative conjunctival vascularization occurred in four patients (6.7%), and this vascularization occurred in the recurrent cases. A significant improvement of visual acuity and corneal clearance was noticed in all patients.ConclusionPreoperative subconjunctival injection of bevacizumab reduces the recurrence rate of pterygium surgery as it reduces the vascular element of the pterygium. Intraoperative application of mitomycin C in addition to preoperative subconjunctival injection of bevacizumab reduces recurrence in recurrent pterygium cases. Further long-term, large-scale studies are recommended.

Long term followup of photorefractive keratectomy with adjuvant use of mitomycin C.

Purpose. To study the long term refractive and visual outcomes of photorefractive keratectomy (PRK) with intraoperative application of mitomycin C (MMC). Methods. This study included 37 eyes who received myopic PRK; after photoablation, a sponge soaked in 0.02% MMC solution was applied in all corneas for 2 minutes. Efficacy, safety, predictability, and stability of PRK MMC were evaluated. Endothelial cell density was evaluated at the last postoperative interval. Results. Mean preoperative spherical equivalent (SEQ) was −6.03 ± 1.87 D (diopters) and reduced to −0.09 ± 0.53 D at the last postoperative examination. Mean followup was 44.73 ± 18.24 months. All the eyes were in the ±1.00 D of attempted versus achieved SEQ at the one-year follow-up interval. Furthermore, 95% of the eyes did not lose lines or gained 1 to 2 lines of CDVA, while 5% lost 1 line. At the third postoperative month, 89% of the eyes either were clear or had trace haze, while 4 eyes had mild haze; by the 12-month postoperative interval, none of the eyes demonstrated haze. Mean endothelial cell density (ECD) at the last postoperative interval was 2658 ± 153 cells/mm2. Conclusions. PRK, with intraoperative use of MMC, demonstrates stable refractive and visual outcomes up to 44 months after surgery.

Use of local mitomycin C in enhancing laryngeal healing after laser cordotomy: A prospective controlled study

The purpose of this study was to investigate the role of intraoperative application of mitomycin C in prevention of glottic restenosis after posterior transverse CO2 laser cordotomy (PTLC) for patients with post-thyroidectomy bilateral vocal fold paralysis. Twenty-five patients with an impaired airway because of bilateral vocal fold paralysis were treated with PTLC. Patients were divided into groups: the mitomycin C group (13 patients) had PTLC and topical mitomycin C; and the control group (12 patients) had PTLC only. No patients in the mitomycin C group developed glottic granulation or laryngeal scarring, whereas 5 of 12 patients in the control group developed granulation (p = .014) and 2 of 12 patients had laryngeal scarring (p = .28). Ten of 13 patients in the mitomycin C group ended up with mild dyspnea with no limitation to normal everyday activities whereas only a third of the control group achieved this outcome (p = .05). The use of topical mitomycin C has been shown to decrease postoperative laryngeal granulation, scarring, restenosis, and the need for revision surgery.