1. Turandot Saul, M.D. St. Luke’s Roosevelt Hospital Center

2.  Consent  Lateral decubitus position  Arch lower back with knees drawn to chest  Sterile field  Local anesthesia  Don mask, gloves

3.  Line at level of iliac crests – L4 spinous process  Spinal cord ends at L1  Interspace above or below  Surface landmark identification accuracy 30% 1 1 Furness, G. et al. An evaluation of ultrasound imaging for identification of lumbar intervertebral level. Anesthesia, 57. 277-280; 2002.

4.  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

5.  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

6.  Morbid obesity  Scoliosis / Arthritis  Anxious  Failed Attempts

7.  Lumbar puncture kit  Linear array, high frequency probe – thin  Curved array, low frequency probe - obese

8.  Ligaments  supraspinal: connects spinous processes  interspinal: inferior to superior border spinous processes  ligamentum flavum - interlaminar space

11. 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.

12.  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.

13.  a: spinous process  b: ligamentum flavum  c: epidural space  d: dura mater  e: 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.

14.  Paramedian  more anatomic elements seen  small window between spinous processes  differentiate dura matter and ligamentum flavum  dynamic guidance

18.  US to localize intervertebral levels  epidural spaces for anesthetic catheters  guidance of neonatal and infant lumbar puncture

19.  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.

20.  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.

21.  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.

22.  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.

23.  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.

24.  Does ultrasound:  increase rate of LP success?  decrease length of procedure  decrease complication rate of procedure  static vs. dynamic

25.  Roberts: Clinical Procedures in Emergency Medicine, 4 th ed. Philadelphia, Saunders; 2004.  Goetz: Textbook of Clinical Neurology, 3 rd 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. 277- 280; 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.