Difference between revisions of "CT before lumbar puncture"

(Text replacement - "==Source== <references/>" to "==References== <references/>")
 
(4 intermediate revisions by 2 users not shown)
Line 1: Line 1:
'''LP without CT is likely safe if:<ref>*NEJM 2001; 345; 1727-33</ref>'''
+
{{CT before LP}}
*History
 
**Age < 60
 
**Not immunocompromised
 
**No history of CNS disease
 
**No seizure within 1 week of presentation
 
*Physical Exam
 
**No ALOC
 
**Ability to answer two consecutive questions successfully
 
**Ability to follow two consecutive commands successfully
 
**Normal [[neurologic exam]]
 
 
''If none of the above, chance of normal ct is 97%; none of the patients herniated''
 
 
 
'''CT findings that prohibit LP:<ref>Emergency Radiology: Case Studies Schwartz</ref>'''
 
*Midline shift
 
**Unequal pressures between the 3 cerebral compartments (left/right supretentorial compartments, posterior fossa)
 
**Intracerebral masses not causing midline shift
 
*Obstructive [[Hydrocephalus]]
 
**Enlargement of ventricles prox to lesions and normal ventricles distal (especially 4th ventricle)
 
*Basilar cisterns compressed
 
**Lateral/3rd ventricles may be small due to diffuse cerebral edema or enlarged due to obstr. hydroceph. +/- shift
 
*Posterior fossa mass
 
**Displacement/compression of 4th ventricle
 
  
 
==See Also==
 
==See Also==
 
*[[Lumbar Puncture]]
 
*[[Lumbar Puncture]]
  
==Source==
+
==References==
 
<references/>
 
<references/>
  
[[Category:Neuro]]
+
[[Category:Neurology]]
 
[[Category:Procedures]]
 
[[Category:Procedures]]
[[Category:Rads]]
+
[[Category:Radiology]]

Latest revision as of 16:50, 25 June 2016

LP without CT is likely safe if:[1]

  • History
    • Age < 60
    • Not immunocompromised
    • No history of CNS disease
    • No seizure within 1 week of presentation
  • Physical Exam

If none of the above, chance of normal ct is 97%; none of the patients herniated

CT findings that prohibit LP:[2]

  • Midline shift
    • Unequal pressures between the 3 cerebral compartments (left/right supretentorial compartments, posterior fossa)
    • Intracerebral masses not causing midline shift
  • Obstructive Hydrocephalus
    • Enlargement of ventricles prox to lesions and normal ventricles distal (especially 4th ventricle)
  • Basilar cisterns compressed
    • Lateral/3rd ventricles may be small due to diffuse cerebral edema or enlarged due to obstr. hydroceph. +/- shift
  • Posterior fossa mass
    • Displacement/compression of 4th ventricle

See Also

References

  1. Computed Tomography of the Head before Lumbar Puncture in Adults with Suspected Meningitis. NEJM 2001; 345; 1727-33
  2. Emergency Radiology: Case Studies Schwartz