In presenting the subject of the direct method of intralaryngeal operation, I do not wish to be considered as championing any particular method. Every laryngologist should be familiar with every method and select for operation in the particular case the method which suits best his personal equation for that case.
The indirect, or mirror, method can be used only in adults. Its greatest disadvantage is that in the guidance of the forceps it requires a movement backward when the image shows that a movement is needed forward, and for a diagonal motion it is necessary to combine a reversed anteroposterior movement with a true lateral movement. In the direct method, all movements are under the control of the eye and are made directly. This does not mean, however, that practice is not required. Many difficulties are to be overcome by continual practice before safe and accurate operation is possible.
JACKSON C. THE DIRECT METHOD OF INTRALARYNGEAL OPERATION. JAMA. 1914;LXIII(22):1918-1922. doi:10.1001/jama.1914.02570220028007