‘Private Practice’ on shaky ground in tumor case
“Private Practice”
“Acceptance” episode, ABC,
Feb. 5, 10 p.m.
The premise
Archer Montgomery (Grant Show), the brother of Dr. Addison Montgomery (Kate Walsh), moves to L.A. and begins working at a rival private practice. A neurologist, he also starts a relationship with Addison’s best friend, fertility specialist Dr. Naomi Bennett (Audra McDonald).
Lying in bed after having sex, Archer suddenly has a generalized seizure -- but refuses to seek treatment and soon returns to work. Naomi insists he be evaluated: “A healthy person your age does not just have a tonic-clonic seizure out of the blue.”
He finally admits to Naomi and later to Addison that he has an inoperable malignant brain tumor (glioma) in a remote location of the brain (near the third ventricle). He says chemotherapy has not been proven effective and radiation would “fry all brain tissue.” Because the tumor is slow-growing (Archer thinks he may have another five years), he decides to only adjust his anti-seizure medications.
But another doctor notices that Archer can’t look up (upward gaze palsy), which he says is not consistent with a tumor of the third ventricle. A CT scan of the brain shows that the mass has doubled in size in just a few weeks and that there are two additional lesions in the upper center of the brain (cortex). Because of the rapid growth and spread, the doctors suspect an infection rather than a tumor, and Archer recalls that he was in Zihuatanejo, Mexico, six months earlier and could have picked up a parasite. A blood test confirms that the brain masses are really tapeworm cysts (neurocysticercosis), which comes from poorly cooked pork.
The neurologist suggests treating the condition with anti-parasitic drugs and steroids to keep the bursting cysts from damaging the brain, but Addison prefers a surgical approach. When Archer develops unremitting seizures (status epilepticus) requiring a medically induced coma, Addison calls her ex-husband, neurosurgeon Derek Shepherd (Patrick Dempsey), to operate.
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The medical questions
Can sexual intercourse provoke a seizure? Is a glioma located near the third ventricle of the brain difficult to remove surgically or to treat medically? Is an upward gaze palsy inconsistent with a tumor of this location? Is neurocysticercosis (caused by tapeworm cysts) common in travelers? Does it have a characteristic appearance on CT scan or MRI and is it confirmed by a blood test? What is the normal treatment for neurocysticercosis? Is general anesthesia useful in treating status epilepticus?
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The reality
Sexual activity, especially in association with alcohol, fatigue or sleep deprivation, can precipitate a seizure in people with a seizure disorder, says Dr. Fred Einesman, an ER doctor and executive story editor and writer on “Private Practice.” Dr. Orrin Devinsky, director of the NYU Epilepsy Center, agrees but adds that this is highly unusual -- reported by less than 1% of patients with seizures.
Most tumors in the third ventricle are benign, though a malignant glioma is very difficult to treat either medically or surgically, as the show suggests. Einesman says a tapeworm cyst could indeed first be mistaken for a glioma if it caused only a single lesion, but Devinsky points out that further scrutiny would be likely considering that less than 1% of gliomas are found in this location and that tumors in this area don’t commonly cause seizures. And Devinsky disputes the contention that Archer’s difficulty looking upward would automatically be considered a symptom of a new lesion in a different location. A cyst of the pineal gland near the third ventricle can cause the same symptoms, he says.
Dr. Jeff Noebels, professor of neurology and neuroscience at Baylor College of Medicine, adds that in the real world a neurologist like Archer who sees the lesion on his own CT scan but doesn’t push to confirm the exact tissue diagnosis with a biopsy or examining cells from the cerebrospinal fluid has “a fool for a patient.”
Neurocysticercosis is caused by the larval cyst of a tapeworm (Taenia solium). The condition is a common cause of seizures in Mexico, Central and South America and Southeast Asia, through accidental ingestion of tapeworm eggs. It has a characteristic appearance on CT scan or MRI (calcification or cysts) and is usually confirmed by an immunological blood test, as the show also demonstrates. Use of anti-parasitic drugs and steroids is a standard therapy that can collapse cysts and diminish seizures.
“In our case, the concern was the rupture of the cyst would release debris which could obstruct the outflow tract,” Einesman says, “therefore, Derek decides to remove it surgically.” In the real world, surgery may in fact be indicated for intraventricular cysts, but the procedure would generally be done with an endoscope rather than an open procedure, says Frank Sorvillo, associate professor in residence at UCLA’s School of Public Health.
Finally, according to Devinsky, unremitting seizures (status epilepticus) are uncommon with neurocysticercosis, especially in this location, but in the rare event that they happen and don’t respond to standard treatments, general anesthesia could be used to induce a coma, likely with the drug pentobarbital or propoful.
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