Objective:

To characterize etiology, risk factors, and management of peri-mesencephalic hemorrhage and severity of clinical presentation in pediatric populations

Background:

Peri-mesencephalic hemorrhage (PMH) is a form of mild subarachnoid hemorrhage (SAH) where the bleed is localized near the midbrain or just anterior to the pons without intraparenchymal or  ventricular extension. It is typically a non-aneurysmal SAH (NASAH) with no clear source of bleeding after extensive vessel imaging including angiogram. Many hypotheses have been proposed such as spontaneous rupture of a perforating artery or an entirely venous source. Traumatic causes are rarely described. Outcomes are typically much better than aneurysmal SAH and other forms of NASAH with very low risk of rebleed, hydrocephalus, and little to no long-term neurologic deficits.

Design/Methods:

case study

Results:

 An 8-month-old developmentally appropriate girl with no prior history of trauma who presented with three episodes of vomiting and lethargy 3-4 hours after a fall from standing position due to loss of balance while she was holding on to a folding chair. She fell backwards onto a tile floor and chair fell on top of her. CTH was obtained which showed prepontine and pontocerebellar hemorrhage spreading to ambient cisterns, IVH of the lateral and 3rd ventricles with acute noncommunicating hydrocephalus and no fracture. CTA with contrast and later MRI brain, MRA, and angiogram did not show any aneurysm or AVM per neurosurgery. EVD was placed with improvement in mental status. Repeat MRI brain was stable with very slight interval increase ventricle, and patient discharged home after 3rd ventriculostomy with no deficits.

Conclusions:

Though rare, trauma is a potential cause of PMH in pediatric populations and can present with acute hydrocephalus due to obstruction of ventricular system successfully treated with EVD placement and 3rd ventriculostomy with positive outcome. Hemorrhage may potentially be due to rupture of small perforating arteries through a sheering force.