ios - issue in Replacing images in document directory and then showing changed image in tableview

Question

i use following code for replacing images in document directory

 NSLog(@"%@",_selectedimage);
        if([self string:pathOfDocDic containsText:@"Test_"]){

            NSLog(@"_selectedName%@",_selectedimage);
            NSData* data = UIImagePNGRepresentation(selectionView1.image);
            [data writeToFile:_selectedName atomically:YES]; 

          // no need to change database cus path going be same             

i just change image by putting new image with same directory path and same name. so after that images get changed in document directory

now problem is when i get back to table view images appear same as before in document directory images is changed but its not getting changed in table view if i close app and start again then it get changed how can i solve this problem?