A 4-day-old premature infant in the neonatal intensive care unit becomes hypotonic and less responsive. She was delivered vaginally at 30 weeks gestation, and her birth weight was 1,200 g (2 lb 10 oz). Physical examination shows a lethargic infant with weak and high-pitched crying, prominent scalp veins, and tense fontanelles. Cranial ultrasound reveals blood in the lateral ventricles. Which of the following structures is the most likely source of the bleeding?

Question

A 4-day-old premature infant in the neonatal intensive care unit becomes hypotonic and less responsive.  She was delivered vaginally at 30 weeks gestation, and her birth weight was 1,200 g (2 lb 10 oz).  Physical examination shows a lethargic infant with weak and high-pitched crying, prominent scalp veins, and tense fontanelles.  Cranial ultrasound reveals blood in the lateral ventricles.  Which of the following structures is the most likely source of the bleeding?

Quizplus · Accepted Answer

11ec160b_35b4_1bab_9249_05c7ca114f27_MD0001_00 Intraventricular hemorrhage (IVH) is a common complication of prematurity that can lead to long-term impairment in neurodevelopment. IVH almost always manifests within the first 5 postnatal days in infants born before 32 weeks gestation and/or with birth weight <1,500 g (3 lb 5 oz). IVH in a newborn can be clinically silent or present with altered level of consciousness, hypotonia, and decreased spontaneous movements. If the bleeding is severe, catastrophic deterioration can occur with a bulging anterior fontanelle, hypotension, tonic-clonic seizures, irregular respirations, and coma. IVH in preterm infants usually originates from the germinal matrix, a highly cellular and vascularized layer in the subventricular zone (source of neurons and glial cells during brain development). The matrix contains numerous fragile, thin-walled vessels lacking the glial fibers that support other blood vessels throughout the brain, making them more susceptible to hemorrhage. Between 24-32 weeks gestation, the germinal matrix starts to become less prominent, and its cellularity and vascularity decrease, leading to a reduced risk of IVH in infants born after 32 weeks. (Choices A and C) In neonates, an assisted delivery (eg, forceps, vacuum) can result in subdural hematoma (cortical bridging veins) or epidural hematoma (middle meningeal artery). Both can cause bulging fontanelles and altered level of consciousness but are characterized by hematomas over the cerebral convexities rather than blood in the lateral ventricles. (Choice D) The sagittal sinus and other dural venous sinuses are channels found between layers of dura mater in the brain. Certain conditions (eg, malignancy, hypercoagulable states, infection) can result in thrombosis within the dural sinuses; however, intraventricular bleeding would not be seen. (Choice E) A ruptured saccular (berry) aneurysm at a branch point in vessels of the circle of Willis is the most common cause of spontaneous subarachnoid hemorrhage (SAH). Aneurysmal SAH is rare in infants and is associated with blood in the basal cisterns rather than the lateral ventricles. Educational objective: Neonatal intraventricular hemorrhage usually originates from the fragile germinal matrix in infants born before 32 weeks gestation and/or with birth weight <1,500 g (3 lb 5 oz). It is a common complication of prematurity that can lead to long-term neurodevelopmental impairment.

A 4-Day-Old Premature Infant in the Neonatal Intensive Care Unit