CT before lumbar puncture: Difference between revisions

Revision as of 22:02, 17 November 2014

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
- 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:^[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

Source

↑ *NEJM 2001; 345; 1727-33
↑ Emergency Radiology: Case Studies Schwartz

Authors:

[1] *NEJM 2001; 345; 1727-33

[2] Emergency Radiology: Case Studies Schwartz

[1]

[2]

@@ Line 1: / Line 1: @@
-==LP without CT is likely safe if==
+'''LP without CT is likely safe if:<ref>*NEJM 2001; 345; 1727-33</ref>'''
-# History
+*History
-## Age < 60
+**Age < 60
-## Not immunocompromised
+**Not immunocompromised
-## No history of CNS disease
+**No history of CNS disease
-## No seizure within 1 week of presentation
+**No seizure within 1 week of presentation
-# Physical Exam
+*Physical Exam
-## No ALOC
+**No ALOC
-## No inability to answer two consecutive questions successfully
+**Ability to answer two consecutive questions successfully
-## No inability to follow two consecutive commands successfully
+**Ability to follow two consecutive commands successfully
-## No gaze palsy
+**Normal [[neurologic exam]]
-## No abnormal visual fields
-## No facial palsy
-## No arm drift
-## No leg drift
-## No abnormal language
-If none of the above, chance of normal ct is 97%; none of the patients herniated
+''If none of the above, chance of normal ct is 97%; none of the patients herniated''
-== CT findings that prohibit LP ==
+'''CT findings that prohibit LP:<ref>Emergency Radiology: Case Studies Schwartz</ref>'''
-#Midline shift
+*Midline shift
-##Look for unequal pressures between the 3 cerebral compartments (left/right supretentorial compartments, posterior fossa)
+**Unequal pressures between the 3 cerebral compartments (left/right supretentorial compartments, posterior fossa)
-##Look for intracerebral masses not causing midline shift
+**Intracerebral masses not causing midline shift
-#Obstructive [[Hydrocephalus]]
+*Obstructive [[Hydrocephalus]]
-##Look for enlargement of ventricles prox to lesions and normal ventricles distal (especially 4th ventricle)
+**Enlargement of ventricles prox to lesions and normal ventricles distal (especially 4th ventricle)
-#Basilar cisterns compressed
+*Basilar cisterns compressed
-##Lateral/3rd ventricles may be small due to diffuse cerebral edema or enlarged due to obstr. hydroceph. +/- shift
+**Lateral/3rd ventricles may be small due to diffuse cerebral edema or enlarged due to obstr. hydroceph. +/- shift
-#Posterior fossa mass
+*Posterior fossa mass
-##Look for displacement/compression of 4th ventricle
+**Displacement/compression of 4th ventricle
 ==See Also==
@@ Line 33: / Line 28: @@
 ==Source==
-*NEJM 2001; 345; 1727-33
+<references/>
-*Emergency Radiology: Case Studies Schwartz
 [[Category:Neuro]]
 [[Category:Procedures]]
 [[Category:Rads]]