Which injection method involves both injection and drainage from the same location?

The one-point injection method is notable for allowing both the injection of embalming fluid and the drainage of blood or bodily fluids to occur from the same injection site. This method is particularly efficient as it simplifies the embalming process, minimizing the need for multiple entry points in the body. By using this technique, the embalmer can administer the embalming solution and simultaneously remove excess fluids, enhancing circulation throughout the body tissues.

The practicality of this method is evident in its ability to maintain a more controlled environment during embalming, as it minimizes tissue displacement and reduces the potential for leakage. Additionally, this approach can help ensure that the embalming fluid is evenly distributed, which is critical for effective preservation and sanitation.

In contrast, the other methods involve different techniques that either focus on separating injection and drainage sites or utilize continuous flow systems without the dual functionality of one-point injection. Each of those methods has its own specific applications and considerations, which might make them suitable in different circumstances or for specific types of cases.