A 4-year-old boy is brought to the office due to headaches that have worsened progressively over the past month and are most severe when lying down. He also has had nonbloody, nonbilious emesis for 2 weeks that typically occurs early in the morning. In addition, the child has intermittent blurry vision, particularly when looking up at the mirror while brushing his teeth. Physical examination shows bilateral papilledema, inability to gaze upwards, and bilateral eyelid retraction. Laboratory testing of sodium, growth hormone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) is normal. Given the early morning emesis and papilledema, a brain mass is suspected and a brain MRI is ordered. Which of the following is the most likely location of the brain lesion in this patient?

Question

A 4-year-old boy is brought to the office due to headaches that have worsened progressively over the past month and are most severe when lying down.  He also has had nonbloody, nonbilious emesis for 2 weeks that typically occurs early in the morning.  In addition, the child has intermittent blurry vision, particularly when looking up at the mirror while brushing his teeth.  Physical examination shows bilateral papilledema, inability to gaze upwards, and bilateral eyelid retraction.  Laboratory testing of sodium, growth hormone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) is normal.  Given the early morning emesis and papilledema, a brain mass is suspected and a brain MRI is ordered.  Which of the following is the most likely location of the brain lesion in this patient?

Quizplus · Accepted Answer

11ec160b_359d_5f33_9249_87dd3d61bd58_MD0001_00 This patient has a pineal gland mass. Classic manifestations of a pineal gland mass include obstructive hydrocephalus from aqueductal stenosis (papilledema, headache, and vomiting) and dorsal midbrain (Parinaud) syndrome due to direct compression of the pretectal region of the midbrain. Parinaud syndrome is characterized by limitation of upward gaze with a downward gaze preference, bilateral eyelid retraction (eg, Collier sign, sclera visible above the superior corneal limbus), and light-near dissociation (eg, pupils that react to accommodation but not to light). Diagnosis of pineal gland mass is made by brain MRI. The most common pineal mass is a germinoma, a midline malignant tumor thought to arise from embryonic germ cells. A germinoma can also arise in the gonads or mediastinum and is more common in young boys. The most common locations for intracranial germinomas are the pineal gland and the suprasellar region (less common site) (Choice A). Due to their proximity to the pituitary gland and hypothalamus, suprasellar germinomas do not lead to Parinaud syndrome, but they are more likely to present with endocrinopathies (eg, central precocious puberty, diabetes insipidus). (Choice B) Primary thalamic tumors are rare. Damage to the thalamus from a mass or more commonly infarction/hemorrhage presents with contralateral hemisensory loss, behavioral changes, and language deficits. (Choice D) Pontine hemorrhage or tumor may cause "locked-in" syndrome, which is characterized by spastic quadriplegia and paralysis of most cranial nerves (CNs) with preserved consciousness and eye movements. (Choice E) The most common cerebellar tumor in children is medulloblastoma, which typically presents with gait and limb ataxia, intention tremor, and nystagmus. (Choice F) Lesions of the medulla can cause lateral and medial medullary syndromes. Lateral medullary (Wallenberg) syndrome leads to contralateral loss of pain and temperature sensations along with ipsilateral paralysis of CNs V, IX, X, and XI. Medial medullary syndrome causes contralateral spastic paralysis, contralateral sensory loss of vibration and proprioception, and ipsilateral flaccid paralysis of the tongue (CN XII). Educational objective: Germinomas are the most common pineal gland tumor and present with obstructive hydrocephalus and dorsal midbrain (Parinaud) syndrome. Germinomas in the suprasellar region cause endocrinopathies due to pituitary/hypothalamic dysfunction. __________ References: Pineal germinoma. (http://www.ncbi.nlm.nih.gov/pubmed/20818311) Pineal region tumors in children. (http://www.ncbi.nlm.nih.gov/pubmed/21042218) Primary brain tumors in adults. (http://www.ncbi.nlm.nih.gov/pubmed/18533376)

A 4-Year-Old Boy Is Brought to the Office Due to Headaches