A 1.5-year-old Chihuahua was presented with clinical signs consistent with multifocal localisation. MRI revealed hydrocephalus internus. Following placement of a ventriculoperitoneal (VP) shunt with a low-pressure valve, improvement was noted. Clinical signs returned one month later. A second MRI revealed subdural haematoma, meningeal reaction and slit-like ventricles, and was interpreted as overshunting. Saline solution was injected in the ventricles via the shunt, which was then ligated. Clinical improvement was noted, followed again by relapse three months later. A third MRI revealed recurrence of hydrocephalus internus. The VP shunt was reconnected and, additionally, the valve was positioned and fixed in a vertical position. A disconnection of the valve occurred two weeks later, and the owners elected euthanasia. Complications following VP shunting in this case reveal many similarities to those described in overshunting in people and should be considered as a possible complication.
