Search In this Thesis
   Search In this Thesis  
العنوان
The Possible Role of Platelet Rich Plasma in Treatment of the Induced Surgical Corneal Injury in Rabbits /
المؤلف
Ibrahim, Nesma Abdelhady Hassan.
هيئة الاعداد
باحث / نسمة عبد الهادي حسن
مشرف / خالــــــد نعيــــــم حمــــــدي
مشرف / هانــي وهيـــب عبد المــلاك
مشرف / مريــــم أسعــــد أميــــن
تاريخ النشر
2023.
عدد الصفحات
257 P. :
اللغة
الإنجليزية
الدرجة
الدكتوراه
التخصص
تشريح
تاريخ الإجازة
1/1/2023
مكان الإجازة
جامعة عين شمس - كلية الطب - قسم التشريح وعلم الاجنة
الفهرس
Only 14 pages are availabe for public view

from 257

from 257

Abstract

The cornea represents the anterior central part of the outer coat that is avascular and transparent to permit light entry into the eye. Since it is the anterior most structure of the eye, its position makes it susceptible to a variety of injuries and insults. In addition, corneal wounds are iatrogenically during refractive surgeries and corneal transplantation surgeries.
The corneal wound healing response is a complex cascade that includes epithelial cells, stromal keratocytes, corneal nerves lacrimal glands, tear film and cells of the immune system through cytokines.
The process of healing after corneal injury requires epithelial cell proliferation and migration, stromal cell death, keratocyte proliferation, myofibroblast generation, collagen deposition, and inflammatory cell infiltration. Corneal wound healing may eventually lead to a fibrotic scar formation resulting in opacity and diminished visual acuity.
Platelet-rich plasma (PRP) is an autologous blood product which consists of a small volume of plasma with a high concentration of suspended platelets reaching to one million platelets per five ml plasma. Platelets contain α-granules that contain growth factors, cytokines and anti-inflammatory factors. These factors are released from platelets up on their activation at wound sites, stimulating proliferation, differentiation and promote healing.
As the PRP contains a supra-physiological platelet concentration, this gives it a healing promotor ability that qualifies it to be used in different fields to promote wound healing in many tissues, including the cornea. PRP is used to treat many corneal conditions like corneal ulcers, dry eye, and corneal wounds whether iatrogenic or traumatic.
We conducted this experimental study to evaluate the ability of the PRP to promote wound healing on the clinical, histological and ultrastructural level in comparison to a control using saline only to maintain corneal hydration. We also assessed the addition of antibiotic to the PRP to test if this will add to the healing promoting ability of the PRP.
Sixty rabbits were included in this study. PRP was prepared from the assigned donor rabbits according to the pre-identified protocol. Corneal injury on the epithelial and stromal level was induced surgically according to our protocol. Rabbits of the three different groups (saline group, PRP group, and PRP plus Vigamox® group) received their assigned treatment and were followed up daily for ten days to measure the size of the epithelial defect under cobalt blue light. Rabbits of the different treatment groups were sacrificed at the pre-specified time points on the third, the seventh, and the tenth days postoperative. Five corneal specimens were subjected to light microscope examination after staining by H&E, Masson Trichrome stain, PAS stain, and immunohistochemistry stain for α-SMA. One corneal specimen was prepared for examination by Scanning Electron Microscopy. The control group animals were sacrificed at one time point and subjected to the same staining, light and Scanning Electron microscope examination for comparison.
This study demonstrated that PRP enhanced corneal wound healing on the clinical, histopathological, ultrastructural, and statistical levels. PRP also resulted in restoration of the regular corneal epithelial surface and regular arrangement of the stromal collagen fibers. Treatment with PRP resulted in almost complete healing of the corneal epithelial wound by the fifth day after surgery in comparison to the positive control where the corneal wound persisted till the tenth day after the experiment.
Antibiotic addition did not result in any further enhancement of the wound healing process. On the contrary, it delayed healing on the clinical, microscopic, ultrastructural and statistical level.
To sum it up, this study found that PRP improved corneal wound healing on almost all levels and resulted in more rapid and more physiological like healing that in turn would maintain the corneal transparency and visual acuity.
Therefore, PRP can be recommended as a therapeutic alternative for treatment of different corneal surface diseases including corneal wounds and corneal ulcers.
However, further research still needed to determine the best and the most proper, cost-effective method for RPR preparation, the treatment doses and frequencies, and the route of administration.
Conclusion and Recommendations
Recommendations for practice
This study adds to the evidence of the benefit of PRP use in corneal wound healing in different circumstances including iatrogenic or traumatic corneal injury resulting, corneal ulcers and dry eye disease. This study proved that PRP initiated normal restoration of the corneal epithelium through clinical, histological, immunohistochemistry, scanning electron microscopy studies. This is mainly due to its high content of different growth factors. Other advantages include ease of preparation, its autologous origin, absence of intolerance.
Recommendations for Future research
This study had certain limitations including its small sample size, the usage of only one antibiotic and one concentration of PRP with one method of preparation.
Therefore, further studies may be needed:
1- To detect effects and possible adverse effects of PRP on the long-term using longer follow up periods.
2- To compare between different preparation methods and different concentration of PRP to detect the best preparation technique and concentration that lead to faster and more physiological-like healing with the least possible adverse effects.
3- To compare between different categories and different concentrations of antibiotics combination with PRP.