http://www.uscg.mil/nmc/medical/NVIC/NVIC_4_08_with_enclosures.pdf
In plain English this Coast Guard document, NVIC 04-08, lists medical conditions that need further review. These conditions do not disqualify anyone from obtaining or retaining US mariner credentials, only that the Coast Guard wants to review them. They approve almost everyone. From the USCG, “72 of 65,000 applications received resulted in a medial denial.” In other words, the chances of denial due to LASIK is naught as long as your doctor doesn’t mess up and ruin your vision.
Excerpt relating to Refractive Surgery (LASIK) as follows:
Subj: MEDICAL AND PHYSICAL EVALUATION GUIDELINES FOR MERCHANT MARINER CREDENTIALS
Enclosure (3) to NVIC 04-08
MEDICAL CONDITIONS SUBJECT TO FURTHER REVIEW
16 Refractive Surgery within past 6 months
Ophthalmology consultation, to include refraction measurement and visual acuity, corneal topography, slit lamp examination looking at the quantity, quality, and extent of incisions, contrast sensitivity testing. Provide completed, type and date of procedure, statement as to any adverse effects or complications (halo, glare, haze, rings. etc.).
Note: Waiver package should be submitted at least, i.e. not sooner than, 4 weeks after the surgery, with a minimum of two stable visual acuities measured, at least two weeks apart.