The atypical congenital pathway of the internal carotid artery (ICA) is an uncommon anatomical variation with a very low prevalence. The medialization of the internal carotid artery is regarded as an infrequent manifestation. The internal carotid artery may be displaced at the level of the pharyngeal wall, leading to the enlargement of connective tissue in the lateral pharynx and retropharyngeal areas. A 76-year-old male patient with a history of weakness on the left side of his body, difficulty swallowing, and speech difficulties was sent to the otorhinolaryngology department because of pain in his throat. He underwent several unsuccessful attempts at the insertion of a nasogastric tube (NGT), which was eventually done with considerable difficulty. Upon evaluation, the individual displayed regular speech and a strength rating of 4/5 in both of his left limbs. Upon examination of the throat, a significant non-pulsating edema was observed in the right retropharyngeal area, pushing the right tonsil anteromedially. A posterior pharyngeal mass was observed during fiberoptic laryngoscopy. The Doppler examination of the carotid arteries yielded definitive results. Computed tomography angiography (CTA) showed the common carotid arteries via a retropharyngeal route. It is clinically significant to identify variations in the course of the internal carotid artery, particularly those located near the submucosal area of the pharynx. This is because there is a higher risk of injury during procedures involving manipulation of the pharynx, such as intubation, insertion of a nasogastric tube, or surgeries in the internal carotid artery region.

A systematic meta-regression analysis of the effects of acute hypoxia on the performance of central executive and non-executive tasks, and the effects of the moderating variables, arterial partial pressure of oxygen (PaO2) and hypobaric versus normobaric hypoxia, was undertaken. Studies were included if they were performed on healthy humans; within-subject design was used; data were reported giving the PaO2 or that allowed the PaO2 to be estimated (e.g. arterial oxygen saturation and/or altitude); and the duration of being in a hypoxic state prior to cognitive testing was ≤6days. Twenty-two experiments met the criteria for inclusion and demonstrated a moderate, negative mean effect size (g=-0.49, 95% CI -0.64 to -0.34, p<0.001). There were no significant differences between central executive and non-executive, perception/attention and short-term memory, tasks. Low (35-60mmHg) PaO2 was the key predictor of cognitive performance (R2=0.45, p<0.001) and this was independent of whether the exposure was in hypobaric hypoxic or normobaric hypoxic conditions.