Allergan, the maker of Botox, said that it would pay about $2.1 billion in cash and shares for Kythera Biopharmaceuticals, which makes a treatment for double chins.

The deal is expected to expand Allergan's product lines for cosmetic facial treatments, particularly by adding Kythera's double-chin treatment, Kybella, which was recently approved for use in the United States by the Food and Drug Administration.

It is the latest in a series of deals in the pharmaceutical sector this year, as drug makers look to strengthen their mix of products through acquisitions. Also, the medical equipment maker Hill-Rom Holdings said it would acquire Welch Allyn, a privately held company that makes diagnostic devices, for $2.05 billion in cash and stock. To read more about the acquisition, click on the link below.

Current approaches for measuring wrinkle reduction tend to rely on static photographs and subjective visual assessment. However, a three-dimensional imaging technique has the capability of measuring whether and how much cosmetic interventions, such as neurotoxin injections, fillers and facelifts work according to a new study.

Researchers from the Perelman School of Medicine at the University of Pennsylvania, describe the procedure, called three-dimensional speckle tracking photogrammetry, in the May issue of Plastic and Reconstructive Surgery. Photogrammetry is the photographic measurement of distance between objects. To read more about this procedure, click on the link below.