Page 103 - AN-3-4

Advanced Neurology Shuntogram technique in programmable valves

Table 1. Summary of shuntogram technique characteristics
in 25 publications
Parameter Value
No. of studies (N) 25
Series 12 (48)
Case studies 11 (44)
Other 2 (8)
Age
Adult 7 (28)
Pediatrics 12 (48)
Both 4 (16)
Neither 2 (8)
Indication
Clinical presentation 13 (52)
Imaging 9 (36) Figure 3. Positioning of the X-ray for oblique view in the sagittal plane for
Positioning ventriculoperitoneal shunt series
Supine 6 (24)
Recumbent 2 (8) novel scintillation camera (fluoroscopy), capturing images
Skin prep at 10, 20, and 60 min, with additional imaging in an erect
Iodine-based cleanser 5 (20) position if migration was not observed after pumping.
Chlorhexidine and alcohol 2 (8) A negative result was verified if, after 6 months, no revision
Asepsis 4 (16) was necessary.
Time Mirfakhraee et al. examined the effect of positioning
12
<10 min 4 (16) using a supine position using the head in a lateral
15 – 45 min 4 (16) orientation. Their timeline for “normal” distal flow was
>45 min 5 (20) narrow, defined as 3 to 9 min; however, only patients with
Pumped manually 4 (16) hydrocephalus on presentation were included in the study.
13
Radio contrast A few years later, Sweeney and Thomas performed a study
Variants of Tc 13 (52) on 250 shuntograms, enrolling patients with irritability,
99m
Metrizamide 2 (8) vomiting, headaches, or pyrexia. Preparation involved
Iopamidol 2 (8) shaving the scalp, employing an aseptic technique, and
using a 23-gauge butterfly needle for CSF aspiration.
Iohexol 3 (12) Iopamidol was injected, with contrast distal to the valve
111 In-DTPA 3 (12) observed and manual pumping applied as needed to assist
Meglumine 1 (4) distal flow. This approach led to 16 false interpretations,
Diatrizoate 1 (4) with nine cases requiring shunt revision. These two studies
Unspecified 5 (20) did not specify how contrast progression was monitored,
Needle gauge and definitions of shunt failure were inconsistently
23 3 (12) applied.
25 7 (28) By 1991, Benzel et al. maintained a supine position
16
Injectate amount for patients 1 h before the procedure, although contrast
<1 mL 1 (4) agents remained variable across institutions. They noted
9,13
3 ml 1 (4) that lowering shunt drainage pressure when the flow was
Changed position 2 (8) initially stalled allowed 18 of 22 shunts to resume flow after
Sensitivity (37.5 – 92.6%) 3 (12) surgically placing a lower-pressure valve. Pumping was
16
Specificity (59.5 – 100%) 3 (12) frequently employed across studies to stimulate flow. 8,16,18
False negative (8 – 25%) 5 (20) However, Piatt’s 27,28 studies in 1992 and 1996 highlighted
False positive (0 – 100%) 4 (16) the limitations of the pumping test, reporting a sensitivity
Note: Values are expressed as n (%) unless otherwise specified. of 50%, specificity of 64%, and a likelihood ratio of 1.39.
Additional reference citations can be found in Table S1. It was concluded that the pumping test alone was neither

Volume 3 Issue 4 (2024) 5 doi: 10.36922/an.4180