What is the cause of a lopsided blood film?

A lopsided blood film typically occurs when the drop of blood is placed off center on the microscope slide. This misplacement affects the distribution of the blood across the slide during the spreading process. When the drop is not positioned properly, it can lead to uneven thickness and coverage, resulting in a film that may appear thicker on one side than the other. This unevenness can hinder accurate microscopic examination and counting of blood cells.

Other factors, such as viscosity, the angle at which the slide is held, and the method of blood collection, can impact the quality of the blood film but do not specifically cause a lopsided appearance. High viscosity could produce a thicker film but wouldn’t inherently lead to a lopsided distribution. Similarly, an incorrect angle might affect the spread quality, but it’s the initial placement of the blood drop that directly creates the lopsided effect. A poor blood collection method could lead to clots or poor sample quality but again is not the primary reason for a lopsided blood film.