Entrapment of the temporal horn: case series and systematic review of literature.

Introduction: Entrapment of the temporal horn (ETH) is a form of focal, obstructive hydrocephalus. Etiology and clinical presentation are diversified. Though known since 1947, standard treatment has not yet been defined. The objective of our study was to perform a systematic review on ETH.

Evidence Acquisition: Data from patients treated at our Institution from 2008 to 2019 were retrospectively collected and analyzed. A systematic PRISMA review of literature was also performed using PubMed and Google Scholar. The following search terms were used: "temporal horn entrapment" [All Fields] OR "trapped temporal horn" [All Fields].

Evidence Synthesis: One hundred and twenty-one cases (mean age 41 years; M/F ratio: 1/1) were analyzed. In 65 (vs. 56) cases (53.7% vs. 46.3%), ETH was not surgery related. Headache was the most common symptom (42%). "Major" treatments were ventriculoperitoneal/ventriculoatrial shunt (42 cases, 34.7%), and endoscopic ventriculocisternostomy (12 cases, 9.9%). In the first group, no perioperative complications were found, 39 patients (92.9%) had a favorable outcome, three patients (7.1%) died for the underlying disease, four cases (9.5%) went through revision; also considering the cases in which another procedure was performed as definitive treatment, there were six shunt failures (13.6%). In the second group, one case (8.3%) developed a deep intracerebral hemorrhage, 11 cases (91.6%) had a favorable long-term outcome, one case (8.3%) had a favorable short-term outcome; also considering the cases in which another procedure was performed as definitive treatment, there were six endoscopic ventriculocisternostomy failures (37.5%).

Conclusions: Described as uncommon, ETH is probably underestimated. Early diagnosis and appropriate treatment are critical. VP shunt is still the most commonly performed treatment. Further randomized clinical trials are, however, needed to establish the gold standard.