TransactionScope vs Transaction in LINQ to SQL

What are the differences between the classic transaction pattern in LINQ to SQL like:

using(var context = Domain.Instance.GetContext())
{
    try
    {
        context.Connection.Open();
        context.Transaction = context.Connection.BeginTransaction();
        /*code*/
        context.Transaction.Commit();
    }
    catch
    {
        context.Transaction.Rollback();
    }         
}

vs the TransactionScope object

using (var context = Domain.Instance.GetContext())
using (var scope = new TransactionScope())
{
    try
    {
        /*code*/
        scope.Complete();
    }
    catch
    {
    }
}