This article [J. Biomed. Opt. 24(12), 121908 (2019) doi: 10.1117/1.JBO.24.12.121908] was originally published online on 17 October 2019 with incorrect measurement units reported in the (1) Sec. 2.2.1, (2) Sec. 3.1, and (3) the $x$ axis label for Figure 2(b).

1) The measurement unit in Sec. 2.2.1 was reported as “$\mu \mathrm{mol}$” rather than “$\mu \mathrm{M}$.”

Original sentence:

“The optimum tubing was determined by comparing photoacoustic images obtained of agar phantoms containing various tube types filled with a $25\text{-}\mu \mathrm{mol}$ ICG solution (Sigma-Aldrich I2633).”

Corrected sentence:

“The optimum tubing was determined by comparing photoacoustic images obtained of agar phantoms containing various tube types filled with a $25\text{-}\mu \mathrm{M}$ ICG solution (Sigma-Aldrich I2633).”

2) Likewise, in Sec. 3.1, the measurement unit was reported as “$\mu \mathrm{mol}$” rather than “$\mu \mathrm{M}$.”

Original sentence:

“Figures 5(a) and 5(b) show a linear relationship between dye concentration and spectrally unmixed PA intensities up to $100\mu \mathrm{mol}$ for MB and $40\mu \mathrm{mol}$ for ICG, respectively.”

Corrected sentence:

“Figures 5(a) and 5(b) show a linear relationship between dye concentration and spectrally unmixed PA intensities up to $100\mu \mathrm{M}$ for MB and $40\mu \mathrm{M}$ for ICG, respectively.”

3) The $x$ axis for Figure 2(b) was incorrectly labeled as “$\mu \mathrm{M}$” rather than “$\mu \mathrm{m}$” (the caption was correct).

Original Fig. 2:

Corrected Fig. 2:

These errors did not impact the results reported in the article. This article was corrected online on 14 November 2019. It appears correctly in print.