Long term evaluation of pterygium excision with conjunctival autografting using autologous blood

Aim: To evaluate the long term outcome of pterygium excision with conjunctival autografting (CAG) using economically viable autologous blood. Materials and Methods: This is a retrospective analysis of total 40 patients who underwent Pterygium excision with CAG using autologous blood as per our inclusion and exclusion criterion. After pterygium excision by avulsion method, we put the 1mm oversized CAG using autologous blood oozing on bare sclera and margins were tucked. Gentle massage for 10 minutes was given. The patients were followed for 48 months to measure the outcome. Results: Our study shows CAG with autologous blood is very effective with zero percent recurrence and retraction of graft. Only in 1 case (2.5%) we have identified gap in graft-host junction as long term complications. This also does not required any intervention as gap was <1mm. Conclusion : Our study shows long term safety, success of economically viable CAG with autologous blood following pterygium excision. © 2020 Published by Innovative Publication. This is an open access article under the CC BY-NC license (https://creativecommons.org/licenses/by-nc/4.0/)


Introduction
Pterygium is a degenerative sub-conjunctival tissue proliferation along with overlying conjunctiva in a triangular fashion, approaching from limbus to papillary centre. It is well known entity for thousands of year BC. It was first described by the great Indian Physician & Surgeon, also known as father of Plastic surgery, Sushruta. 1,2 The etiology or cause of pterygium is largely unknown, 9 but mostly it is attributed to exposure of UV radiation 10 hot air and dusty wind. 3,4 The medical management is largely oriented towards temporary symptomatic relief to the patient, while Surgery is the mainstay treatment in present scenario. [5][6][7][8] The scope of surgery varies from traditional Pterygium excision with bare sclera to modern Robotic Pterygium Surgery. 9 In present era, the most widely accepted technique is Conjunctival Autografting (CAG) with different techniques like suture, fibrin glue, autologous serum. [5][6][7][8] This is a retrospective study. All patients had been operated between April 2014 to April 2015. Our aim of the study was to report recurrence and acceptance of graft with complication present, if any.

Materials and Methods
This is a retrospective clinical study. We have included total 40 patients in our study matching our inclusion criterion. Our inclusion and exclusion criterion were as follows- On 48 months follow-up, patient was examined for Graft retraction, rejection, granuloma or any other complication as well as recurrence.

Pre-Operative Evaluation
All patient underwent routine OPD procedures like complaints and history taking, Vision assessment and Refraction, IOP, Slit lamp examination, 90D. All patients, who met our inclusion criteria and passed on OPD examination, were counseled well before surgery and Informed consent was taken from them and relatives before surgery. We have followed standard guidelines and adhered to the tenets of Declaration of Helsinki.

Procedure
The eye was anaesthetized using 0.5% Proparacaine solution 3-4 times, 10 minutes apart, preoperatively. The procedure was simple avulsion of pterygium head from corneal bed and thereafter body of pterygium was dissected from sclera and excised. Minor bleeding point was not cauterized while major bleeding point, if any, was cauterized with bipolar cautery. The remnants of conjunctival tissue was scrapped off from cornea using 15 No surgical blade. Bare sclera was measured carefully using Castroviejo calipers. The conjunctival autograft (1mm more from bare sclera size) was taken from supero-temporal quadrant avoiding tenon's tissue. Oozing of blood from minor blood vessels was confirmed and autograft was placed, taking care of limbal orientation. The graft was tucked under the conjunctiva near the margin and was gently ironed with the help of curved suturing forceps for 10 minutes until adherence was confirmed with gentle touch of sponge at the edge of graft. Eye was patched after putting Moxifloxacin and Dexamethasone combination drops. The patients were examined on Post-Operative Day 1, 1 week, 1month, 6 months and 48 months for graft edema, hemorrhage, retraction, loss or rejection. Routine postoperative medication of Moxifloxacin with Dexamethasone eye drop started in tapering dose and continued for 6 weeks.

Results
In our study total 40 patients enrolled as per inclusion criterion. The age ranged from 20 yrs. to 77 yrs. of age with an average age 45.3. In our study male:female ratio is 1:1, i.e. 20 Male & 20 Female. All pterygium was Nasal in location. In 40 patients, 23 Right eyes and 17 Left eyes operated upon. All patients had been operated for cosmesis and various symptoms like redness, burning sensation, pain, headache etc.   In our study the maximum number of patients, 34(85%) were between age of 20-60 yrs. of age, and minimum numbers 6 patients (15%) in between 61-80 yrs. of age. In our study 16 patients (40%) were operated in young age between 20-40 yrs. due to cosmetic reason. Table 2 shows the laterality of pterygium in comparison to age distribution. It is clear that unilateral pterygium is more common in young population without any sex predilection while bilateral pterygium is seen commonly in 41-60 yrs of age group.
From table 3 we can see that, on 1 week follow-up, graft edema was noted in 13 cases (32.5%) with small size graft (5*5mm), which was done mostly in younger age group while retraction was noted in 4 cases (10%) where graft size was large (5*7 mm or more). Also note that there was only 1    On 48 months follow-up, all the 40 cases were having stable graft without any complication except 1 case (2.5%) where a minimal gap (<1mm) was noted between graft and host conjunctival junction in large graft of 7*8mm. No intervention was done for this case as the gap was minimal with no exposed episcleral tissue. Although there are many reported complications 5-8 like granuloma formation, graft rejection, recurrence but we have not noted any long term complications except minimal graft-host junction gap in 1 case.

Discussion
There are several indications for pterygium surgeries, including cosmesis, watering, redness, burning sensation. 10 Also there are different techniques of conjunctival autografting using Sutures, fibrin glue and autologous serum with different outcomes. 11,12 There are multiple advantages of using autologous blood for graft adhesion compared to fibrin glue like no risk of acquired infection like Parvovirus and HIV, less chances of inflammation and the most importantly low cost.
In our study, all 40 grafts were stable and well accepted without any graft loss or recurrence, comparable with other studies like Kulthe et al, 10 Sharma et al, 13 Roopa KS et al. 14 In Kulthe et al 10 study, they studied 79 eyes, Sharma et al studied 25 eyes and Roopa KS et al 14 studied 50 eyes for 6 months with zero recurrence rate. Our study followed the patient for 48 months with zero recurrence rates. Hemlatha BC et al 12 had also reported zero recurrence rate in 6-30 months of follow-up. Thatte S et al 15 had followed cases for 6 months to 5 yrs. and reported recurrence in3 cases (1.98%) in large and fleshy primary pterygium.
However in our study, we have noted a minimal gap (< 1mm) between graft-host junctions without exposure of underlying episclera, on 48 months follow up as long term complication. In this case, larger graft size of 7*8mm was used. This gap was noted on 1 week follow-up also but no intervention was done as this was minimal and well epithalialized. Suryavanshi MP et al 16  There are studies reporting graft retraction and graft losses 10,14 in 6 months follow-up but there was no confined reason put behind. We tried to improve outcome of CAG by increasing graft size to 1mm and tucking under the host conjunctiva as it gives more mechanical stability, we can hypothesize. On literature search we found similar study done by Roopa KS et al 14 and Kulthe et al, 10 in later study graft size was only 0.5mm oversized. There has not been any study showing advantage or disadvantage of taking oversized graft. Elwan SA 17 reported early retraction of graft in 6 eyes (12%) due to graft edema and chemosis where glue was used for Autografting which was managed well by medical management. Only one case required suturing in their study, though they have not mentioned the graft size in patient who underwent suturing. In our study also there was 1case (2.5%) with early graft retraction, graft size was 7*9mm, which subsided with medical management after 1 week. Thatte S et al 15 has also reported retraction in 9 case (5.96%) where graft size was bigger (>7-5mm) which correlates well with our study.
Our study also shows similar short term signs and complications like graft edema, graft hemorrhage, early graft retraction as in other studies. 10,[12][13][14]16 but most of the complications resolved in long term as shown in table 3.

Conclusion
Our study confirms the long term success and safety of conjunctival autografting using autologous blood. Moreover it's an economical and risk free method of sutureless, glueless autografting after pterygium excision.

Limitations
All retrospective study has the limitation of bias, although we have tried to rule out bias by choosing patients randomly. Also the sample size is small in our study but strength of our study is long term follow-Up. We further suggest prospective, multicentric clinical study of different types of pterygium surgery with long term outcome.

Source of Funding
None.

Conflict of Interest
None.