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Suresh Magge

Sudden blindness leads to unusual diagnosis

Suresh Magge

Suresh N. Magge, M.D., and his colleagues at Children’s National recently published the details of an unusual case of advanced moyamoya disease in the journal Stroke.

When Children’s National Health System Neurosurgeon Suresh N. Magge, M.D., met his new patient, the 16-year-old had suddenly lost her vision in both eyes.

To discover the reason for this abrupt loss of vision, her doctors ran a battery of tests. An ophthalmologist found no problems with her eyes.  Her optic nerves, which run signals generated from the eyes to the brain, also appeared to work normally. However, a computerized tomography scan and magnetic resonance imaging showed the unmistakable signs of a stroke in her occipital lobe, the portion of the brain responsible for interpreting signals relayed from the optic nerves.

“Her brain basically wasn’t seeing what her eyes saw,” Dr. Magge explains.

Delving deeper, her Children’s National care team found the reason why their young patient had suffered a stroke by using a cerebral angiogram, an imaging test that shows the blood vessels in and around the brain. The teen had moyamoya disease, a rare condition that causes blood vessels in the brain to narrow, often leading otherwise healthy adults and children to have strokes.

According to the National Institutes of Health, moyamoya is Japanese for “puff of smoke,” so named because of the telltale signs this condition presents on an angiogram. When arteries in the brain narrow, brain tissue becomes “thirsty” for more blood, Dr. Magge explains, leading its cells to produce chemicals that prompt new blood vessels to grow. These new collateral blood vessels often grow in a thin tangle that looks like smoke on an angiogram. Generally, however, they do not supply sufficient oxygenated blood to meet the brain’s needs, leaving it starved for oxygen. Eventually, the blood supply can get so low that patients suffer transient ischemic attacks, “mini-strokes” that temporarily deprive the brain tissue of oxygen, or full-blown strokes typically characterized by weakness, speech problems, facial paralysis or other problems.

Dr. Magge’s patient had little warning before her stroke occurred. The first major symptom that led her to seek medical attention was abrupt blindness, which Dr. Magge says is a highly unusual occurrence for a moyamoya diagnosis. That’s why he and colleagues decided to publish the details of her case as a teaching report April 14, 2017 in the journal Stroke.

The Children’s National co-authors wrote that once their patient was diagnosed with a stroke due to advanced moyamoya disease, with blood vessels severely narrowed throughout her brain, the first order of business was stabilizing her symptoms and making sure she did not have further strokes. Her blood pressure was stabilized, and she was started on aspirin therapy to decrease her risk of further strokes. She took time to recover as much as possible from her original stroke.

A few weeks later, Dr. Magge and his neurosurgery colleagues performed a type of surgery to revascularize – or restore blood flow – to areas of the brain that were still healthy but at risk of having subsequent strokes. The surgical procedure, known as pial synangiosis, reconfigures the brain’s blood vessels to make sure that these vulnerable areas of the brain have a sufficient blood supply.

Years later, Dr. Magge says, his patient is doing well, except for the original blindness, a permanent consequence of the stroke to her occipital lobe before her diagnosis. She has not had new strokes since the revascularization surgery. She will need aspirin therapy and periodic neurological checkups for the rest of her life, Dr. Magge explains, to make sure that the blood supply to her brain remains stable.

Children’s experts use a team approach to treat patients with complex care needs: Neurologists, neurosurgeons, intensivists, hematologists, anesthesiologists, neuroradiologists and nurses leverage their combined expertise with moyamoya disease to treat the complexities of this condition.

“A team approach is essential to deliver the best outcomes to children with life-changing diseases,” Dr. Magge says. “We try to help kids get back to living full and healthy lives.”

Blood Transfusion

Hydroxycarbamide effective in sickle cell stroke prevention

Blood Transfusion

Hydroxycarbamide treatment is on par with blood transfusions for preventing stroke in patients with sickle cell anemia.

What’s known

Strokes are common and devastating complications for patients with sickle cell anemia, often leading to severe and lifelong motor and neurocognitive problems for people with this congenital blood disorder. Results of a clinical trial published in 1998 showed that having regular blood transfusions could reduce the risk of having a first stroke by 90 percent in children with sickle cell anemia. Since then, doctors have employed this prophylactic treatment widely. However, blood transfusions can be painful, inconvenient and carry substantial risks themselves — including the potential of blood-borne infections, iron overload and immune-related reactions to blood products. Finding a way to reduce stroke risk without over-relying on blood transfusions could substantially benefit patients with sickle cell anemia.

What’s new

A team of researchers, including Naomi L.C. Luban, M.D., a Children’s National Health System hematologist and laboratory medicine specialist, tested transfusions against a drug treatment called hydroxycarbamide in a clinical trial to see if the pharmaceutical intervention could reduce strokes at least as well as transfusions. The clinical trial, known as “TCD With Transfusions Changing to Hydroxyurea (TWiTCH),” assigned 60 patients with sickle cell anemia who had abnormally high transcranial Doppler (TCD) flow velocities—a measure of blood flow in the brain that suggests elevated risk of stroke—to receive hydroxycarbamide instead of transfusions. The research team compared the outcomes for these patients with 61 other patients who received standard prophylactic transfusions. Over the 24-month study period, neither group experienced any strokes, although three transient ischemic attacks (a temporary blockage of blood flow in the brain) occurred in each group. These comparable findings suggest that hydroxycarbamide treatment, also known as hydroxyurea, is on par with transfusions for preventing strokes in patients with sickle cell anemia.

Questions for future research

Q: Does hydroxycarbamide offer a long-term way for patients with sickle cell anemia to avoid transfusions?
Q: Could hydroxycarbamide help patients with sickle cell anemia who already have suffered a stroke or who have had severe problems with blood vessels in their brains that impair blood flow?
Q: Which other treatments can help patients avoid the myriad complications that accompany sickle cell anemia?

Source: Hydroxycarbamide versus chronic transfusion for maintenance of transcranial doppler flow velocities in children with sickle cell anemia—TCD With Transfusions Changing to Hydroxyurea (TWiTCH): A multicentre, open-label, phase 3, non-inferiority trial.” Ware, R.E. B. R. Davis, W. H. Schultz, R.C. Brown, B. Aygun, S. Sarnaik, I. Odame, B. Fuh, A. George, W. Owen, L. Luchtman-Jones, Z.R. Rogers, L. Hilliard, C. Gauger, C. Piccone, M.T. Lee, J.L. Kwiatkowski, S. Jackson, S.T. Miller, C. Roberts, M.M. Heeney, T.A. Kalfa, S. Nelson, H. Imran, K. Nottage, O. Alvarez, M. Rhodes, A.A. Thompson, J.A. Rothman, K.J. Helton, D. Roberts, J. Coleman, M.J. Bonner, A. Kutlar, N. Patel, J. Wood, L. Piller, P. Wei, J. Luden, N.A. Mortier, S.E. Stuber, N. L. C. Luban, A.R. Cohen, S. Pressel and R.J. Adams. Published by The Lancet on Feb. 13, 2016.