Third ventriculostomy and endoscopic aqueductoplasty in a child with isolated fourth ventricle after intraventricular hemorrhage of prematurity

Background: Isolated fourth ventricle represents a challenging complication of posthemorrhagic hydrocephalus in premature newborns. Traditional therapeutic strategies include direct shunting of the fourth ventricle or microsurgical approaches. With the advancement of neuroendoscopic techniques, endoscopic aqueductoplasty has emerged as a minimally invasive alternative aimed at restoring fluid circulation between the fourth and third ventricles, with or without the use of aqueductal stents. This video illustrates tunneling aqueductoplasty with an intraventricular catheter under direct vision as an effective option in the treatment of isolated fourth ventricle of posthemorrhagic etiology. Case Description: We present a case of a 2-year-old pediatric patient with a history of hydrocephalus secondary to intraventricular hemorrhage of prematurity (Papile grade III). At 2 months of age, due to extreme prematurity (27 weeks) and low birth weight, an Ommaya device for repeated ventricular punctures was implanted. At 4 months of age, a ventriculoperitoneal shunt was implanted in the left frontal horn. He remained neurologically stable with adequately treated hydrocephalus until the age of 2, when he began experiencing progressive symptoms of valvular dysfunction (irritability, vomiting, and changes in respiratory pattern). He was readmitted, where a cranial computed tomography (CT) scan revealed ventriculomegaly, especially in the fourth ventricle (isolated ventricle) with signs of brainstem compression. The patient then underwent cerebral endoscopy for endoscopic third ventriculostomy and aqueductoplasty through tunneling of the intraventricular catheter through the cerebral aqueduct, restoring cerebrospinal fluid (CSF) circulation and peritoneal shunt. A follow-up CT scan of the head showed adequate shunt from the fourth and third ventricles to the peritoneum, with significant decompression of the brainstem. The patient was discharged on the 5 th postoperative day. At present, he has been under outpatient follow-up for approximately 6 months, showing no signs of intracranial hypertension or brainstem dysfunction and with adequate neuropsychomotor development. Conclusion: This case highlights a practical strategy for managing hydrocephalus associated with an isolated fourth ventricle. Under direct endoscopic visualization, tunneling with an intraventricular catheter allowed restoration of CSF diversion through a ventriculoperitoneal shunt, illustrating a feasible technical solution in this challenging scenario.