In a sixth nerve palsy one would expect that, over the 6 month observation period, most patients would show the following pattern of changes to their ocular muscle actions: firstly, an overaction of the medial rectus of the affected eye, then an overaction of the medial rectus of the contraletral eye and, finally, an underaction of the lateral rectus of the unaffected eye - something known as an inhibitional palsy. These changes serve to reduce the variation in the misalignment of the two eyes in different gaze positions (incomitance). Where this process has fully developed, the preferred option is a simple recession, or weakening, of the medial rectus of the affected eye, combined with a resection, or strengthening, of the lateral rectus of the same eye. However, where the inhibitional palsy of the contralateral lateral rectus has not developed, there will still be gross incomitance, with the disparity between the eye positions being markedly greater in the field of action of the affected muscle. In such cases recession of the medial rectus of the affected eye is accompanied by recession and/or posterior fixation (Fadenoperation) of the contraleral medial rectus.The same approaches are adopted bilaterally where both eyes have been affected. See also
Congenital fourth nerve palsy

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Gastric volvulus or volvulus of stomach is a twisting of all or part of the stomach by more than 180 degrees with obstruction of the flow of material through the stomach, variable loss of blood supply and possible tissue death. The twisting can occur around the long axis of the stomach: this is called organoaxial or around the axis perpendicular to this, called mesenteroaxial. Obstruction is more likely in organoaxial twisting than with mesenteroaxial while the latter is more associated with ischemia. About one third of the cases are associated with a hiatus hernia. Treatment is surgical. The classic triad (Borchardts Triad) of gastric volvulus, described by Borchardt in 1904, consists of severe epigastric pain, retching (due to sour taste in mouth) without vomiting, inability to pass a nasogastric tube and reportedly occurs in 70% of cases. Sometimes severe pain at the top of left shoulder, this may be due to internal bleeding irritating the diaphragm upon respiration. Classification
Organoaxial type
In an organoaxial gastric volvulus, the stomach rotates around an axis that connects the gastroesophageal junction and the pylorus. The antrum rotates in opposite direction to the fundus of the stomach. This is the most common type of gastric volvulus, occurring in approximately 59% of cases, and it is usually associated with diaphragmatic defects. Strangulation and necrosis commonly occur with organoaxial gastric volvulus and have been reported in 5–28% of cases. The key imaging feature of organoaxial volvulus is that the greater curvature is located above the lesser curvature of the stomach.