A 6-year-old girl is brought to the clinic by her parents after multiple falls while running in the past few months. Over the past month, the patient has also had intermittent headaches, with increased frequency in the past 2 weeks. The headaches are worse in the morning and have occasionally been accompanied by nausea and vomiting. Examination shows a tired-appearing young girl. The patient walks with a wide-based gait and has difficulty with heel-to-toe walking. Eye examination reveals bilateral abducens nerve palsies and papilledema. The remainder of the cranial nerve examination is normal. Strength is 5/5 in bilateral upper and lower extremities. Sensation is intact, and reflexes are 2+ bilaterally. Babinski testing reveals plantar flexion of the toes. Which of the following is most likely responsible for this patient's symptoms?

Question

A 6-year-old girl is brought to the clinic by her parents after multiple falls while running in the past few months.  Over the past month, the patient has also had intermittent headaches, with increased frequency in the past 2 weeks.  The headaches are worse in the morning and have occasionally been accompanied by nausea and vomiting.  Examination shows a tired-appearing young girl.  The patient walks with a wide-based gait and has difficulty with heel-to-toe walking.  Eye examination reveals bilateral abducens nerve palsies and papilledema.  The remainder of the cranial nerve examination is normal.  Strength is 5/5 in bilateral upper and lower extremities.  Sensation is intact, and reflexes are 2+ bilaterally.  Babinski testing reveals plantar flexion of the toes.  Which of the following is most likely responsible for this patient's symptoms?

Quizplus · Accepted Answer

11ec25c8_d599_4094_bc81_ab67152ad83e_MD0003_00 This patient's signs of cerebellar dysfunction and increased intracranial pressure (ICP) are concerning for a posterior fossa tumor. In children, the most common posterior fossa tumors are medulloblastoma and pilocytic astrocytoma. posterior fossa tumor Most medulloblastomas occur in the vermis of the cerebellum, which coordinates balance and gait. Therefore, patients classically have truncal or gait ataxia, as in this patient with frequent falls. Examination may show a wide-based gait and poor heel-to-toe coordination. Cerebellar hemisphere involvement may cause problems with limb coordination, such as dysmetria and intention tremor. A medulloblastoma that compresses the fourth ventricle can result in obstructive hydrocephalus and increased ICP, with findings of morning headache, vomiting, and papilledema (as in this patient). Elevated ICP can also cause bilateral abducens nerve palsies (ie, inability to abduct the eyes) because the nerve's long intracranial course makes it particularly vulnerable to compression or stretching at the skull base. medulloblastoma Medulloblastomas have the potential for leptomeningeal spread and are treated aggressively with surgery, radiation, and chemotherapy. (Choice A) Acoustic neuroma, a typically benign tumor of the vestibulocochlear nerve, presents with hearing loss, tinnitus, and mild gait unsteadiness (due to vertigo). Large tumors can compress the cerebellum and cause ataxia. However, this tumor is extremely rare in children, and this patient has no auditory symptoms. (Choice B) Craniopharyngioma occurs in the pituitary stalk and can cause headache, vomiting, and visual changes. However, ocular findings include temporal field vision loss due to optic chiasm compression, not abducens nerve palsy. In addition, cerebellar dysfunction would not be seen. (Choice C) Glioblastoma is an aggressive, supratentorial malignant tumor that usually presents with headache, seizures, and focal neurologic deficits (eg, motor weakness). This patient's cerebellar dysfunction makes this diagnosis unlikely. (Choice E) Meningioma is a benign, extraaxial tumor that may present with seizure and focal defects based on tumor location, such as visual field defects if the optic pathway is involved. Meningioma is extremely rare in children, and cerebellar involvement is atypical. (Choice F) Pinealoma may present with signs of increased ICP due to obstructive hydrocephalus. However, patients typically have Parinaud syndrome, which is characterized by limitation of upward gaze, light-near dissociation, and eyelid retraction (none of which are seen in this patient). Educational objective: Posterior fossa tumors typically present with signs of cerebellar dysfunction (eg, ataxia) and increased intracranial pressure (eg, headache, vomiting, papilledema). In children, the most common posterior fossa tumors are pilocytic astrocytoma and medulloblastoma. References: Medulloblastoma. (http://www.ncbi.nlm.nih.gov/pubmed/26336203)

A 6-Year-Old Girl Is Brought to the Clinic by Her