Turandot Saul, M.D.
St. Luke’s Roosevelt Hospital Center
ULTRASOUND GUIDED
LUMBAR PUNCTURE
PREPARATION

Consent
Lateral decubitus position
Arch lower back with
knees drawn to chest
Sterile field
Local anesthesia

Don mask, gloves




SURFACE LANDMARK GUIDANCE

Line at level of iliac crests – L4 spinous process

Spinal cord ends at L1

Interspace above or below

Surface landmark identification accuracy 30%1
1Furness,
G. et al. An evaluation of ultrasound imaging for identification of lumbar
intervertebral level. Anesthesia, 57. 277-280; 2002.
SURFACE LANDMARK GUIDANCE

Inability to identify landmarks leads to
 reluctance
to perform procedure
 higher rates of complication
 patient discomfort

Alternatives
 treatment
without CSF sample
 fluoroscopy - transport, radiation, availability
 ultrasound guidance
ULTRASOUND FOR LUMBAR PUNCTURE
Easy to use
 Non-invasive
 Increasingly available


Information essential to a successful LP
 site
of needle introduction
 angle needed to approach sub-arachnoid space
 distance needed to obtain CSF
THE DIFFICULT LUMBAR PUNCTURE
Morbid obesity
 Scoliosis / Arthritis
 Anxious
 Failed Attempts

EQUIPMENT
Lumbar puncture kit
 Linear array, high frequency probe – thin
 Curved array, low frequency probe - obese

ANATOMY

Ligaments

supraspinal: connects
spinous processes

interspinal: inferior to
superior border spinous
processes

ligamentum flavum interlaminar space
ULTRASOUND - LONGITUDINAL
ULTRASOUND - TRANSVERSE
MEDIAN VS. PARAMEDIAN APPROACH
Images: Ferre, RM and Sweeney, TW. Emergency physicians can easily obtain ultrasound images of anatomical landmarks relevant to
lumbar puncture. American Journal of Emergency Medicine. 25(3); 2007.
ULTRASOUND - MEDIAN APPROACH



a: spinous processes
b: dura mater /
ligamentum flavum
c: subarachnoid space
Images: Ferre, RM and Sweeney, TW. Emergency physicians can easily obtain ultrasound images of anatomical landmarks relevant to
lumbar puncture. American Journal of Emergency Medicine. 25(3); 2007.
ULTRASOUND – PARAMEDIAN APPROACH





a:
b:
c:
d:
e:
spinous process
ligamentum flavum
epidural space
dura mater
subarachnoid space
Images: Ferre, RM and Sweeney, TW. Emergency physicians can easily obtain ultrasound images of anatomical landmarks relevant to
lumbar puncture. American Journal of Emergency Medicine. 25(3); 2007.
MEDIAN VS. PARAMEDIAN ?

Paramedian
 more
anatomic elements seen
 small window between spinous processes
 differentiate dura matter and ligamentum flavum
 dynamic guidance
DIRECTION AND DEPTH
US GUIDANCE FOR LUMBAR PUNCTURE
US GUIDANCE FOR LUMBAR PUNCTURE
RADIOLOGY AND ANESTHESIA

US to localize intervertebral levels
 epidural
spaces for anesthetic catheters
 guidance
of neonatal and infant lumbar puncture
ULTRASOUND GUIDANCE FOR LP

Ultrasonography in neonatal and infant lumbar
puncture
47 patients referred for image guided LP
 ultrasound provided information

 presence
or absence of CSF
 cause of the failed lumbar puncture
 whether to proceed with further attempts
Coley, BD, et al. Diagnostic and interventional ultrasonography in neonatal and infant lumbar puncture Pediatric
Radiology (2001) 31; 399-402.
EPS CAN OBTAIN ULTRASOUND IMAGES OF LP
ANATOMICAL LANDMARKS

2 emergency physicians
5
structures (spinous processes, ligamentum
flavum, dura, epidural space, subarachnoid space)

76 patients, all landmarks identified
 average
BMI = 31
 88% < 1 minute, 100% < 5 minutes
Ferre, RM and Sweeney, TW. Emergency physicians can easily obtain ultrasound images of anatomical landmarks relevant to
lumbar puncture. American Journal of Emergency Medicine. 25(3); 2007.
THE USE OF ULTRASOUND TO IDENTIFY PERTINENT
LANDMARKS FOR LP

Stratified patients by BMI

Recorded difficulty in palpating landmarks

US to identify spinous process of L3, L4, L5,
ligamentum flavum and spinal canal
Stiffler, KA et al. The use of ultrasound to identify pertinent landmarks for lumbar puncture. American Journal of
Emergency Medicine. 25(3); 2007.
THE USE OF ULTRASOUND TO IDENTIFY PERTINENT
LANDMARKS FOR LP

Difficulty in palpating landmarks - 21 patients
 5%
normal BMI (< 24.9)
 33% overweight (24.9 - 30)
 68% obese (> 30)

US identified pertinent structures
 16/21
(76%)
Stiffler, KA et al. The use of ultrasound to identify pertinent landmarks for lumbar puncture. American Journal of
Emergency Medicine. 25(3); 2007.
THE USE OF ULTRASOUND TO IDENTIFY PERTINENT
LANDMARKS FOR LP

Distance: skin to ligamentum flavum
 44mm
normal BMI (< 24.9)
 51mm overweight (24.9 - 30)
 64mm obese (> 30)
Stiffler, KA et al. The use of ultrasound to identify pertinent landmarks for lumbar puncture. American Journal of
Emergency Medicine. 25(3); 2007.
FUTURE STUDIES

Does ultrasound:
 increase
rate of LP success?
 decrease length of procedure
 decrease complication rate of procedure
 static vs. dynamic
RESOURCES





Roberts: Clinical Procedures in Emergency Medicine, 4th ed.
Philadelphia, Saunders; 2004.
Goetz: Textbook of Clinical Neurology, 3rd ed. Philadelphia, Saunders;
2004.
Stiffler, KA et al. The use of ultrasound to identify pertinent
landmarks for lumbar puncture. American Journal of Emergency
Medicine. 25(3); 2007.
Furness, G. et al. An evaluation of ultrasound imaging for
identification of lumbar intervertebral level. Anesthesia, 57. 277280; 2002.
Ferre, RM and Sweeney, TW. Emergency physicians can easily obtain
ultrasound images of anatomical landmarks relevant to lumbar
puncture. American Journal of Emergency Medicine. 25(3); 2007.