High-resolution manometry (HRM) is a diagnostic tool for surgeons, gastroenterologists and other healthcare professionals to evaluate esophageal physiology. The Chicago Classification (CC) system is based on a consensus of worldwide experts to minimize ambiguity in HRM data acquisition and diagnosis of esophageal motility disorders. The most updated version, CCv4.0, was published in 2021; however, it does not provide step-by-step guidelines (i.e., for beginners) on how to assess the most important HRM metrics. This paper aims to summarize the basic guidelines for conducting a high-quality HRM study including data acquisition and interpretation, based on CCv4.0, using Manoview ESO analysis software, version 3.3 (Medtronic, Minneapolis, MN).

OBJECTIVE: Absent contractility is considered a disorder of peristalsis. The literature about the etiology and clinical characteristics is scarce and the evidence on systemic diseases associated with this esophageal disorder is limited. Therefore, we aimed to determine the etiology of absent contractility in our population using the clinical algorithm recently described in the literature.
METHODS: We conducted a retrospective, descriptive study at a single tertiary hospital of all patients diagnosed of absent contractility between May 2018 and February 2020. Data on demographic characteristics, medication, comorbidities, and laboratory and paraclinical tests were recorded from clinical records.
RESULTS: A total of 72 patients with absent contractility were included for analysis. There was a predominance of female sex (n=43, 59.7%), with a mean age of 55.4 (±15.0) years. We identified a systemic disorder associated with absent contractility in 64 (88.9%) patients. From these, 31 (43.1%) patients were diagnosed with a systemic autoimmune disease, 26 (36.1%) patients were considered to have absent contractility secondary to pathological exposure to acid-reflux and 15 (20.8%) patients were diagnosed with other non-autoimmune systemic disorders. In the remaining eight (11.1%) patients, there were no underlying systemic disorders that could justify the diagnosis of absent contractility.
CONCLUSIONS: A systematic approach to search for an underlying cause in patients diagnosed with absent contractility is warranted. Up to 90% of patients with absent contractility have a systemic disorder associated with this condition.

Fluoroscopic studies of the gastrointestinal tract are becoming increasing less common due to the introduction of other imaging techniques such as computed tomography and magnetic resonance imaging and to the increased availability of endoscopy. Nevertheless, fluoroscopic studies of the gastrointestinal tract continue to appear in clinical guidelines and some of their indications are still valid. These studies are dynamic, operator-dependent examinations that require training to obtain the maximum diagnostic performance. This review aims to describe the technique and bring the indications for this imaging modality up to date.