There are several places need to modify to add extra text at X-cart Product Name.

1. For Products at X-cart Homepage and Detailed Category Page:
Go to /2-columns/customer/main/products_t.tpl, and change
{$current_category.category} {$product.product|amp}
to:
{if $main eq "catalog" && $current_category.category eq ""}
Cheap Eyeglasses {$product.product|amp}
{elseif $main eq "catalog" && $current_category.category ne ""}
{$current_category.category} {$product.product|amp}
{/if}

2. For Product Names at Detailed Product Page, go to /common_files/customer/main/product.tpl
Change:

{$product.producttitle|amp}

to:

Prescription Eyeglasses {$product.producttitle|amp}

Here just add “Prescription Eyeglasses” as what we need to add.

3. Product Names within Customer Also Bought ( at the end of Detaild Product Page), go to /common_files/customer/simple_products_list.tpl, and change
{$product.product|amp}
to:
Discount Eyeglasses {$product.product|amp}
Here we add “Discount Eyeglasses” as extra text.

4. Product Name with Bestsellers
Go to /common_files/modules/Bestsellers/menu_bestsellers.tpl, and change:
{$b.product|amp}{$b.product|amp}
to:
Eyeglasses {$b.product|amp}
Here we add “Eyeglasses” as extra text.

5. Product name within Recently Viewed, go to /common_files/modules/Recently_Viewed/content.tpl, and change:
{$rviewed_products[i].product|amp}
to:
Eyeglasses {$rviewed_products[i].product|amp}
Here we also add “Eyeglasses” as extra text.

The above method has been tested successfully at X-cart Gold V4.4.4