Difficult lumbar puncture
A traumatic CSF tap can affect laboratory results showing falsely
elevated cell counts and CSF protein. Increasing degenerative
spondylosis and obesity has increased the number of failed attempts.
Also, the fear of negligence suit has persuaded physicians to refer such
procedures to radiologist.29 Further, there is an
increase in the number of complex spinal surgeries, leading to further
restriction of access to the CSF through bedside blind trials. With an
increase number of complex spine surgeries, the access to the CSF space
is better with image-guided Lumbar puncture than blind trials. There is
an increase in number intrathecal medications , which are costly and
therefore preference is being given for imaging confirmation leading to
the favor of image guided LP.29 All these have led to
an increase in the number requests for image guided LPs for both
diagnostic and therapeutic procedures, especially fluoroscopic guided
LP. FG-LP is generally considered a safe procedure with a good
efficacy,59 minimal radiation exposure (n= 2.9 mSv),
2.2 % developing PLPH, with only 0.8% requiring EDBP, nerve root
irritation and infectious complications have not been reported yet, even
from centres which perform 1000 FG-LPs per year.60,61However, these facilities are not available widely, especially in
resource strained countries. In such settings, when physicians encounter
a dry tap, they can first confirm the needle position with a cross-table
lateral radiograph and correct dehydration. The following flowchart
details the manoeuvres that can be applied in case of a dry tap.{Figure 5 } .62