148 CLINICAL BACTERIOLOGY AND HEMATOLOGY 



punctures, but in favourable cases the period of relief gets longer 

 and the relapses milder, until the disease is cured. In a case in 

 which I performed the operation recently a single puncture was 

 followed by immediate relief, though the symptoms were most 

 grave, and complete and permanent cure ensued. Great tempo- 

 rary relief may also be given in the severe headache of uraemia 

 and chlorosis. 



It is not advisable to do it on a " walking '' patient, since if too 

 much fluid is drawn off headache or vomiting are said to result ; 

 these soon pass off if the patient rests in bed. 



Requisites. — i. A suitable needle. In children the spinal 

 meninges will be reached at a depth of 3 to 4 centimetres (roughly 

 I to i^ inches), whilst in adults the depth may be twice as great. 

 The needle should not be less than 2^ inches long for an infant 

 and 4 inches for an adult, and should be sharp and strong. An 

 antitoxin needle will usually serve very well. A syringe is 

 unnecessary, and the fluid should never be sucked out of the 

 • 



4rSc 



Fig. 27. — Author's Needle for Lumbar Puncture. 



spine, or injury to the nerve-roots may result. The needle should 

 always have a sharp and stiff wire inside it when the puncture is 

 made, otherwise it may become blocked by a shred of fibrous 

 tissue picked up during its passage through the parietes, and 

 time may be lost in sterilizing a wire with which to clear it. 

 Another use for the wire arises from the fact that when the 

 intracerebral pressure is low the needle may push the membrane 

 in front of it, instead of perforating it : when this is the case a 

 short sharp push with the wire will probably puncture the 

 membrane, and the point of the needle will slip in. A piece of 

 steel wire is best. 



Since cultures may have to be taken, it is advisable to have 

 some sort of a handle which may be sterilized with the needle and 

 avoid any necessity for a very elaborate sterilization of the hands. 

 I use a pair of artery forceps, one blade of which is passed inside 

 the barrel and the other outside, and the instrument clipped on. 

 The two are sterilized together and the forceps used as a handle 



