TY  - CHAP
M1  - Book, Section
TI  - Stroke and Cognitive Dysfunction
A1  - Stotesbury, Hanne
A1  - Adams, Robert J.
A1  - Kirkham, Fenella J.
A2  - Gladwin, Mark T.
A2  - Kato, Gregory J.
A2  - Novelli, Enrico M.
PY  - 2021
T2  - Sickle Cell Disease
AB  - Among  the  most  debilitating  and  poorly  understood  complications  of  sickle  cell  disease  (SCD)  are  the  conditions  affecting  the  central  nervous  system  (CNS),  including  cerebrovascular  disease  and  diffuse  structural  abnormalities  associated  with  clinical  and  silent  stroke,  seizures,  headache,  and  cognitive  impairment  (Figure  9-1).1  Neurologic  complications  affect  at  least  25%  of  SCD  patients2  and  are  often,  but  not  always,  associated  with  underlying  large-vessel  vasculopathy.3  There  is  a  broad  spectrum  of  acute  and  chronic  complications1;  some  of  the  risk  factors  are  universal,  but  others  appear  to  be  specific  and,  in  some  cases,  paradoxical.4  Ischemic  and  hemorrhagic  stroke  may  occur  in  the  context  of  acute  illness,  including  chest  and  vaso-occlusive  crises,  or  “out  of  the  blue.”5  In  addition,  seizures,  headache,  and  coma  are  common  in  patients  with  SCD.1,6-8  Advances  in  neuroimaging  have  demonstrated  evidence  for  large-vessel  and,  potentially,  small-vessel  involvement,  along  with  hemodynamic  stress,  both  in  symptomatic  clinical  stroke  and  apparently  asymptomatic  patients  with  covert  or  silent  cerebral  infarction.1  Screening  for  large-vessel  vasculopathy  with  transcranial  Doppler  ultrasound  (TCD;  Cases  1  and  2)  and  magnetic  resonance  angiography  (MRA;  Cases  1,  2)  and  for  parenchymal  damage  (ischemic  and  hemorrhagic;  Cases  2-11)  with  magnetic  resonance  imaging  (MRI)  is  now  established.1  Computed  tomography  (CT)  may  be  essential  for  acute  diagnosis  and  emergency  management  of  ischemia  (Case  3)  or  hemorrhage  (Cases  9  and  11),  and  arterial  or  venous  occlusion  (Cases  3  and  4),  although  because  the  radiation  dose  is  high,  magnetic  resonance,  including  magnetic  resonance  venography  (MRV;  Case  7),  should  be  organized,  if  possible.  Management  strategies  currently  focus  on  blood  transfusion  and  hydroxyurea.1  Follow-up  from  the  Stroke  Prevention  in  Sickle  Cell  Anemia  (STOP)  trials  has  demonstrated  that  if  children  aged  2  to  16  years  with  abnormal  TCD  cerebral  blood  flow  velocities  (time-averaged  mean  maximum  velocity  >200  cm/s;  Case  1)  are  regularly  transfused  indefinitely,  the  majority  of  pediatric  strokes  are  preventable.9,10  The  Transfusions  Switching  to  Hydroxyurea  (TWiTCH)  trial  showed  noninferiority  for  continuing  with  hydroxyurea  at  maximum-tolerated  dose  in  those  with  abnormal  time-averaged  mean  maximum  velocities,  but  normal  MRA,  transfused  on  the  STOP  protocol  for  1  year.11  Chronic  transfusion  for  children  aged  5  to  14  years  with  silent  cerebral  infarction  was  shown  to  prevent  further  infarction,  particularly  clinical  stroke,  in  the  Silent  Infarct  Transfusion  (SIT)  trial.12  Bone  marrow  transplantation  has  been  used  for  secondary  stroke  prevention  in  some,  and  revascularization  is  an  option  if  there  is  intracranial  vessel  occlusion  with  collateral  formation  (moyamoya).10  
SN  - 
PB  - McGraw-Hill Education
CY  - New York, NY
Y2  - 2024/04/19
UR  - hemonc.mhmedical.com/content.aspx?aid=1179338709
ER  -