Say Goodbye to “Human Eye Identification”? — Unveiling Computer-Assisted Sperm Analysis (CASA) Technology

Say Goodbye to “Human Eye Identification”? — Unveiling Computer-Assisted Sperm Analysis (CASA) Technology

In the past, laboratory technicians had to manually count sperm one by one under a microscope, a labor-intensive process prone to errors. Today, an increasing number of hospitals are adopting a cutting-edge technology called Computer-Assisted Sperm Analysis (CASA), making semen analysis faster and more objective.

So how does CASA work?

Think of it as a “high-speed intelligent documentary” for sperm. First, a drop of semen sample is placed on a specialized counting slide under a microscope connected to a high-speed camera. The instrument then captures and records a video of sperm motility, with the computer automatically identifying and tracking the movement trajectory of every sperm within the field of view. Through complex algorithms, the computer then calculates key sperm parameters like concentration and motility. More importantly, it provides kinematic data difficult for the human eye to assess precisely, such as:

- Speed: How fast is the sperm moving?

- Pattern: Is it moving in a straight line or circling?

The advantages of CASA lie in:

- Greater objectivity, eliminating subjective differences between technicians;

Greater efficiency, with analysis speeds far exceeding manual methods;

Greater precision, offering rich kinematic data that provides additional clues for clinical diagnosis.

Of course, CASA is not infallible. If the sample contains excessive impurities or severe sperm agglutination, the computer may misidentify sperm. In such cases, manual intervention is required to correct the computer's misidentifications. Additionally, for special cases like azoospermia or retrograde ejaculation, experienced technicians must confirm findings under a microscope.

CASA serves as a powerful tool for sperm quality assessment in andrology labs and animal breeding facilities, ushering semen analysis into an era of digitalization and standardization. However, it remains an “assistant” to physicians. Final diagnoses and treatment plans still require professional doctors to formulate based on comprehensive evaluations.