PMC9109486_01
Electroencephalography on admission showing generalized, irregular
delta-theta activity as well as triphasic waves in average montage. EEG was
recorded by surface electrodes following the 10/20 system using the
following parameters: sensitivity 7 microV/mm, time constant 0.3 s, 70 Hz
low-pass filter and 50 Hz notch filter.
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Electroencephalography (EEG) showed generalized, irregular delta-theta activity as well as triphasic waves (see Figure 1) and laboratory testing revealed hyperammonemia of 121 mug/dl (reference range 19-55 mug/dl) despite normal liver and kidney function.
Serum levels of ammonia over time during hospitalization.
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Serum levels of ammonia decreased (see Figure 2) and clinical improvement was observed under this treatment regimen.
Portocaval shunt from inferior mesenteric vein (IMV) to left renal vein and
inferior vena cava (IVC), respectively, on coronally reformatted computed
tomography (CT, a) and digital subtraction angiography (b-g). (a) Initial CT
imaging showed a vascular convolute left of the aorta (bracket), connecting
the IMV (arrowhead) to the left renal vein (arrow). After percutaneous
puncture of the right portal vein (b, arrowhead) selective catheterization
of the superior mesenteric vein (c, arrowhead) showed main drainage of blood
through retrogradely perfused IMV (c, curved arrow). Diagnostic contrast
injection into IMV visualized feeding portal vein (d, arrowhead) and
draining vessels into left renal vein (e, arrow) and IVC (e, arrowhead).
Stationary contrast agent (f, *) after coil embolization of draining vessels
with IDC and microplex coils (f, arrowheads) proved efficient occlusion.
Final diagnostic contrast injection confirms change of perfusion direction
of IMV toward the liver (g, curved arrow).
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Finally, computed tomography (CT) angiography revealed a left abdominal venous convolute with portosystemic shunts between the inferior mesenteric vein and the left renal vein as well as the inferior vena cava (see Figure 3(a)). The patient underwent percutaneous transhepatic coil embolization and the shunts were successfully obliterated (Figure 3(b)-(g)), resulting in full and sustained clinical recovery with serum ammonia levels remaining within the normal range.
Electroencephalography after portocaval shunt obliteration showing a
posterior alpha rhythm with no encephalopathic changes in average montage.
EEG was recorded by surface electrodes following the 10/20 system using the
following parameters: sensitivity 7 microV/mm, time constant 0.3 s, 70 Hz
low-pass filter and 50 Hz notch filter.
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EEG before discharge showed a posterior alpha-rhythm with no encephalopathic changes (see Figure 4).