Blindness due to glaucoma Ahmad I, Khan BS Pakistan Journal of Ophthalmology, 2020, Vol. 36 (3): 267-271 267 ORIGINAL ARTICLE Recurrence Rate of Primary Pterygium Following Excision with Mitomycin C versus Excision with Amniotic Membrane Transplant Jawad Humayun 1 , Mubashir Rehman 2 , Mohammad Farhan 3 , Muhammad Kashif Karman 4 Shahid Adbur-Rauf Khan 5 1-3 Nowshera Medical College, Qazi Hussain Ahmad Medical complex, Nowshera, 4 DHQ Hospital, Mishtimela District Orakzai, 5 Hayatabad Medical Complex, Peshawar ABSTRACT Purpose: To compare recurrence rate of primary pterygium following excision with mitomycin c verses excision with amniotic membrane transplant. Study Design: Quasi experimental study. Place and Duration of Study: Qazi Hussain Ahmad Medical Complex, Nowshera, from January 2019 to June 2019. Material and Methods: One hundred and two patients presenting for the first time with pterygium were included in the study and were divided into two groups. Patients having conjunctivitis, blephritis, keratitis or any other ocular inflammatory condition and patients having history of chemical burns and symblepharon were excluded from the study. Group A underwent surgical excision with 0.02% mitomycin–C application for 3 minutes and Group B was surgically treated with application of amniotic membrane. Patients of both groups were followed up for six months to detect recurrence of pterygium. Data was analyzed using SPSS version 20. Frequency and percentages were calculated for categorical data like age, gender and recurrence rate. Recurrence rate was stratified among age and sex to see the effect modifiers. Results: Mean age in both groups was 39.98 ± 9.11 years. In group A, 64.70% patients were males and in group B, 62.74% patients were male. Recurrence of Pterygium was seen in 21.5% patients in group A and 7.84% in group B. The difference was statistically significant with a p value of 0.05. Conclusion: Recurrence rate of primary pterygium following excision with mitomycin C is higher than excision with amniotic membrane transplant. Key Words: Pterygium, Mitomycin-C, Amniotic membrane. How to Cite this Article: Humayun J, Rehman M, Farhan M, Karman MK, Khan SAR. Recurrence Rate of Primary Pterygium Following Excision with Mitomycin C Versus Excision with Amniotic Membrane Transplant. Pak J Ophthalmol. 2020; 36 (3): 267-271. Doi: 10.36351/pjo.v36i3.1033 INTRODUCTION Pterygium is a fibrovascular in growth of degenerative Correspondence to: Mubashir Rehman Nowshera Medical College, Nowshera E. mail: drmubashirrehman78@gmail.com Received: April 2, 2020 Revised: April 17, 2020 Accepted: May 4, 2020 The limbus onto the cornea 1 . Ultraviolet exposure, hot climates and chronic surface dryness are the risk subepithelial bulbar conjunctival tissue extending over factors for the development of the pterigium 2 . It can lead to complications like astigmatism and inflammation. Histologically it is an elastotic degenerative change in the vascularized sub-epithelial stromal collagen 3 . mailto:drmubashirrehman78@gmail.com Jawad Humayun, et al 268 Pakistan Journal of Ophthalmology, 2020, Vol. 36 (3): 267-271 Treatment of pterygium includes medical and surgical modalities. Medical treatment includes tears substitute, topical steroids and sunglasses 4 . Different surgical procedures used for the treatment are bare sclera technique, simple conjunctival flap, conjunctival auto-grafting, adjunctive treatment with Mitomycin C or Beta irradiation, amniotic membrane patch grafting and occasionally peripheral lamellar keratoplasty 5,6 . Each procedure is associated with certain recurrence rates. Multiple studies have been done comparing different surgical procedures 7 . Mitomycin C (MMC) is an alkylating agent, which has been used during pterygium surgery to reduce chances of recurrence. MMC causes cell death by inhibiting DNA synthesis. It is applied directly over the sclera using sponges during pterygium surgery. It acts by inhibition of fibroblast proliferation in the episcleral region and hence reduces chances of recuirrence 8 . One of the methods to cover the gap created by pterigium excision is to use amniotic membrane graft over the bare sclera. Amniotic membrane has also been used in other ocular surface diseases such as persistent corneal epithelial defects, chemical burns, Stevens–Johnson syndrome and ocular cicatricial pemphigoid 9 . Amniotic membrane grafts reduce chances of recurrence of pterygium because of their anti-inflammatory properties and cause suppression of transforming growth factor β signaling and fibroblast proliferation, hence promoting epithelial healing. Studies have shown that recurrence rates of Pterygia following amniotic membrane graftingis between 14.5% and 27.3% 10 . Our study intends to compare the recurrence rate of pterygium following excision with mitomycin-c and excision with amniotic membrane transplant. MATERIAL AND METHODS The study was conducted at the department of Ophthalmology, Qazi Hussain Ahmad Medical Complex, Nowshera. Non-probability consecutive sampling technique was used. Sample size was calculated using WHO calculator, P1; proportion of recurrence rate in mitomycin group = 40% 6 , P2; proportion of recurrence rate in amniotic membrane transplant group = 14.6% 7 , power of test = 90% and keeping confidence interval = 95% (CI), the sample size was 51 patients in each group. Total sample size was 102. All those patients presenting for the first time with pterygium, both genders and age 18 – 60 years were included in the study. Patients with recurrent pterygium, conjunctivitis, blephritis, keratitis or any other ocular inflammatory condition and patients having history of chemical burns and symblepharon were excluded from the study. All patients were divided into two groups using non probability consecutive sampling. Group A was treated with surgical excision with 0.02% mitomycin–C application for 3 minutes and group B was treated with surgical excision and application of amniotic membrane. Amniotic membrane was retrieved by getting placenta from patients booked for elective C-section in the OBS/Gynae department. The patients were sero- negative for Hepatitis B and C. Amniotic membrane was separated from Chorion and was scrapped to remove debris. All the debris/blood was washed with antibiotic cocktail in Balanced Salt solution (Ampicillin, Streptomycin and Amphotericin-B). After surgery, patients were given eye drops of Moxifloxacin and Dexamethasone. Patients of both groups were followed up for six months to detect recurrence of pterygium on slit lamp examination. Data was analyzed using SPSS version 20. Frequency and percentages were calculated for categorical data like age, gender and recurrence rate. Chi square test was applied on the two groups to see the difference between the two groups. P value ≤ 0.05 was considered significant. Recurrence rate was stratified against age and sex to see the effect modifiers. RESULTS A total of 102 patients were divided in two equal groups; Patients in group A underwent primary Table 1: Age Distribution (n = 102). Age Group Group A (n = 51) Group B (n =51) 18 – 30 years 12 (23.52%) 12 (23.52%) 31 – 40 years 18 (35.29%) 18 (35.29%) 41 – 50 years 11 (21.5%) 11 (21.5%) 51 – 60 years 10 (19.6%) 10 (19.6%) Total 51 (100%) 51 (100%) Mean and SD 40.35 ± 9.62 39.98 ± 9.11 Table 2: Efficacy (n = 102); Chi square test was applied in which P value was 0.050. Efficacy Group A (n = 51) Group B (n = 51) Effective (no recurrence) 40 (78.43%) 47 (92.15%) Not effective (recurrence) 11 (21.5%) 04 (7.84%) Total 51 (100%) 51 (100%) Recurrence Rate of Primary Pterygium Following Excision with Mitomycin C versus Excision with Amniotic Membrane Transplant Pakistan Journal of Ophthalmology, 2020, Vol. 36 (3): 267-271 269 Table 3: Stratification of Efficacy with Age (n = 102). Age Efficacy Excision with Mitomycin C Excision Amniotic Membrane Transplant P value 18 – 30 years Effective 09 11 0.273 Not effective 03 01 Total 12 12 31 – 40 years Effective 14 17 0.148 Not effective 04 01 Total 18 18 41 – 50 years Effective 09 10 0.534 Not effective 02 01 Total 11 11 51 – 60 years Effective 08 09 0.531 Not effective 02 01 Total 10 10 Table 4: Stratification of Efficacy with Gender. Gender Efficacy Excision with Mitomycin C Excision amniotic membrane transplant P value Male Effective 28 29 0.478 Not effective 05 03 Total 33 32 Female Effective 14 18 0.131 Not effective 04 01 Total 18 19 pterygium excision with MMC and group B had pterygium excision with Amniotic membrane transplant. Age distribution among two groups is shown in table no 1. In both groups, 35.29% patients were in ages between 31 – 40 years. Mean age was 39.98 ± 9.11. Male were more than females in both groups i.e. in group A, 33 (64.70%) patients were male where as in group B, 32 (62.74%) patients were male. Recurrence was seen in 21.5% patients of group A and 7.84% patients of group B. Stratification of efficacy with age and gender is given in table number 3 and 4. DISCUSSION Pterygium is one of the most common disorders in tropical and subtropical region 11 . Most important risk factors are exposure to sunlight, hot, windy dry weather and old age 12 . Short body height is also cited in literature as a risk factor for pterygium development. It causes irritation, redness and affects the visual acuity either by directly affecting the visual axis or by producing changes in the corneal curvature 13-14 . Yu C et al compared the efficacy of amniotic membrane transplantation, corneal limbus stem cell conjunctival transplantation and pedicle conjunctival flap transposition in the treatment of pterygium and observed that the recurrence rates of pterygium for the three surgeries were 14.6%, 13.9% and 7.7%, respectively. No significant difference was identified when comparing the recurrence rate between any two groups 15 . Zeng et al in their meta-analysis compared limbal conjunctival autograft and other adjuvants for pterygium excision. They stated that the recurrence rates after pterygium excision with limbal conjunctival autograft were lower as compared to pterygium excision with bare sclera technique (P < 0.01), bulbar conjunctival autograft (P < 0.01), and with use of mitomycin C (P < 0.01). However, there was no statistically significant difference in the recurrence rates after limbal conjunctival autograft and amniotic membrane graft (P = 0.39) 16 . Liang W et al compared the recurrence rate of pterygium excision with conjunctival autograft versus pterygium excision with amniotic membrane graft and found that conjunctival autograft group had low recurrent rate; 6 eyes (7.4%) versus amniotic membrane transplantation group; 10 eyes (19.2%) 17 . The recurrence rates in our study were similar to Koranyi G et al who compared outcome of a 4 years study on pterygium excision using mitomycin C with suturing a free conjunctival autograft and found that the recurrence rate was 38% in mitomycin C group and 15% in conjunctival autograft group (p < 0.05) 18 . Kheirkhah A et al compared the prevention of recurrence in patients with primary or recurrent pterygium using adjunctive mitomycin C application following pterygium excision with free conjunctival autograft versus conjunctival-limbal autograft. They observed that in free conjunctival autograft group no eye developed pterygium recurrence; however, two eyes (5.1%) in conjunctival-limbal autograft group developed recurrence, including one patient (3.2%) with primary pterygia and one patient (12.5%) with recurrent pterygia with no statistically significant difference in recurrence rates between the two groups or in the primary and recurrent pterygium groups 19 . Salman AG et al compared the recurrence rate after limbal stem cell transplantation versus amniotic http://www.ncbi.nlm.nih.gov/pubmed?term=Koranyi%20G%5BAuthor%5D&cauthor=true&cauthor_uid=20528781 http://www.ncbi.nlm.nih.gov/pubmed?term=Kheirkhah%20A%5BAuthor%5D&cauthor=true&cauthor_uid=22153864 Jawad Humayun, et al 270 Pakistan Journal of Ophthalmology, 2020, Vol. 36 (3): 267-271 membrane transplantation as ocular surface reconstructing procedure. They also evaluated the use of antimetabolite drugs as an adjunctive therapy for amniotic membrane transplantation and conjunctival autograft. They observed that the recurrence rate was 10% in limbal stem cell transplantation plus conjunctival autograft group, 30% in amniotic membrane transplantation group and 20% in mitomycin C plus amniotic membrane transplantation group. The rate of recurrence was statistically significantly between the three groups (P < 0.001) 20 . Fakhry observed that in pterygium excision and limbal-conjunctival autograft transplantation group there were four cases of recurrences while in group operated with injection of 0.1 mL of mitomycin-C, 0.15 mg/mL one month before limbal-conjunctival autograft transplantation surgery, there was one case of recurrence 21 . Hafez MI compared one-year outcome of two procedures for primary pterygium excision with MMC and excision with suturing a free conjunctival autograft. The recurrence rate of MMC group was 40% compared with 5.3% in conjunctival autograft group 22 . The limitation of our study was that it was a single centered study. Moreover, a comparison was only made between two adjuvants. CONCLUSION Recurrence rate of primary pterygium following excision with mitomycin C has a higher recurrence rate as compared to excision with amniotic membrane transplant. Ethical Approval The study was approved by the Institutional review board/Ethical review board. 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