If a puncture as you say or a hole is found in retina it must be lasered immediately. It is a completely safe procedure if done by an expert. More safer if the hole is in periphery than holes near macula. The procedure is simple, after dilating your fathers eye the doctor using a laser machine will put laser spots all around the hole which will prevent any fluid going in between the two layers of retina and causing what is called as Retinal Detachment. If in doubt you can take a second opinion and if the second doctor also says there is a hole, you must immediately go for laser. If hole and that too a single one is the only problem then this will only take one laser sitting.