A fluoroscopic unit that includes remote control is mandatory. Spot-film imaging is also important for documentation of anatomy. Videorecording is important for functional evaluation. Modern image intensifiers have a high spatial and contrast resolution. This equipment enables high-quality videorecording which actually makes interpretation easy. Moreover, with a high-quality digital system it is not necessary to use conventional cassette films anymore. Flat-panel detectors (FPD) are solid-state X-ray digital radiography devices similar in principle to the image sensors used in digital photography and video. Amorphous selenium FPDs are X-ray photons converted directly into charge. Flat-panel detectors are sensitive and fast. Their sensitivity allows a lower dose of radiation [6, 7]. They are lighter, smaller in volume, and more accurate. FPD has replaced videofluoroscopy. Therefore the radiologic evaluation should be integrated in the RIS/PACS system of the radiologic department. Recording should be obtained continuously. It is important to monitor all swallows, particularly the first swallow as this often appears to be the worst swallow.

The radiologic examination has to include all structures involved in swallowing from the lips to the stomach. But according to the above clinical history the examination is usually focused on one or two specific areas. If there is a high suspicion of misdirected swallowing, the laryngeal vestibule should be included from the beginning in lateral projection. It is very common that the first swallow is the worst swallow, and that only the first swallow will reveal misdirected swallowing. On the other hand, in a patient with suspected misdirected swallowing, it is important that at the end of the examination when the esophagus has been examined and the patient has swallowed several boluses the status in the laryngeal vestibule should be documented, because sometimes the misdirected swallowing is revealed only at the end. In patients with a suspicion of esophageal abnormalities it is important to start the examination with evaluation of the esophagus. That could even mean starting with a solid bolus before the esophagus is extended by air or too much barium is retained.

It is important to distinguish between two types of radiologic examinations. One is custom-tailored for revealing the cause of the patient’s symptoms, which means the worst swallow. The other examination is the therapeutic swallowing study which is custom-tailored by either introducing maneuvers or different viscosities or other boluses for compensation of abnormalities [8]. This therefore can be described as how to achieve the best swallow. Different modes of decompensating a compensated swallow are also important [9]. It is always important to observe many swallows because dysfunction may be intermittent.

Radiology of swallowing relies on a systematic approach. One has to look specifically at certain areas of the swallowing apparatus. These can be divided into seven functional units, namely [1] tongue, [2] soft palate, [3] epiglottis, [4] hyoid and larynx, [5] pharyngeal constrictor, [6] pharyngoesophageal (PE) segment, and [7] esophagus.

Fluoroscopy has to begin before the ingestion of the bolus. Fluoroscopy of the pharynx should also include a few seconds after the passage of the bolus into the esophagus. It is important not to change the position of the central beam during fluoroscopy because otherwise the anatomic details will be unsharp. The bolus should enter and leave the film sequence. The central beam should not follow the bolus. However, in the esophagus in the prone position, the bolus moves slowly at a speed of 1–4 cm/s and should be followed by the central beam from the pharynx to the stomach.