Johnson & Johnson has reached an agreement to buy the eye health unit of Abbott Laboratories for about $4.3 billion in cash. The unit, called Abbott Medical Optics, makes eye drops and contact lens cleaners, as well as equipment used for cataract surgery and laser vision correction procedures. Abbott bought the business for $2.8 billion in 2009.

Abbott is selling the unit in order to focus on its treatments for the heart and arteries. The deal is expected to close by April. The closing is subject to antitrust clearance and other customary closing conditions.

The acquisition will boost Johnson & Johnson’s vision business, which includes Acuvue contact lenses. According to Johnson & Johnson’s Ashley McEvoy, eye health is one of the largest, fastest growing, and most underserved segments in health care today. The global eye-health market is estimated to be about $68 billion.

Cataract surgery is one of the most commonly performed surgeries and the No. 1 cause of preventable blindness. The World Health Organization estimates that approximately 20 million people are blind from age-related cataracts and at least 50 million people with compromised visual acuity caused by cataracts. These numbers rise year after year due to population growth and increasing life expectancy.

Abbott’s medical-optics business recorded $1.1 billion in sales last year, down 6.9 percent year-over-year. No margins or profit metrics were released alongside the transaction. Johnson & Johnson had $25.1 billion in medical-device sales during the same period. Johnson & Johnson generates the majority of its sales from pharmaceutical products.

Johnson & Johnson sees the deal immediately adding to its adjusted earnings after the close. The company has traditionally relied on organic growth, but growth rates have been sluggish for years. Revenues have grown by roughly $10 billion over the past 10 years to roughly $72 billion now, amounting to just 1-2 percent per year. Johnson & Johnson’s stock has risen 25 percent over the past year.

There has been a wave of mergers among medical-device companies in recent years. Abbott, based in Abbott Park, Ill., recently made a deal to buy St. Jude Medical Inc. and its portfolio of cardiovascular devices for roughly $25 billion. Johnson & Johnson, based in New Brunswick, N.J., bought device maker Synthes Inc. for roughly $20 billion in 2012. Johnson & Johnson also made a $3.3 billion purchase of Vogue, which closed in July, and acquired NeoStrata and NeuWave Medical earlier this year. The terms of those deals have not been disclosed.

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