As you know, lenses come in various hardness, so a soft lens is always much easier to remove.
The older you get, the harder the lenses. When the lens is harder, you require more ultrasound power. The lens can be more adherent and this increases the complications.
There are certain subtypes as well. Some cataracts are very adherent to the surrounding capsule, which makes surgery more complicated.
There are other reasons why surgery can be more complicated related to the anatomy of the eye. Some eyes are just smaller, some eyes are super big. There are many factors. I think it's all in the training of every eye doctor in Singapore to manage different kinds of cataract.
