Introduction: Flow sufficiency of the superficial temporal artery stump (STA) compared to the internal maxillary artery (IMAX) in flow replacement bypass surgery for cerebral aneurysms has not been established. Here, we quantitatively assess the flow-carrying capacity of the STA stump and IMAX.
Methods: External carotid artery catheter-based angiograms of 10 consecutive patients at our institution were retrospectively reviewed. STA stump and IMAX vessel diameters were measured from the angiograms. STA stump and IMAX flows were measured directly in a single patient using quantitative magnetic resonance angiography (QMRA). Flows were also analyzed according to Poiseuille’s law: Q = Pi deltaP r^4 / 8 eta L.
Results: 10 patients were included. STA and IMAX vessel diameters measured from angiograms ranged between 2-3 mm and were nearly the same diameter in each patient. Vessel diameters measured using QMRA in 1 patient were: right STA 2.6 mm, right IMAX 3.3 mm, left STA 2.9 mm, left IMAX 2.8 mm. Vessel flows measured using QMRA in the same patient were: right STA 34.0 mL/min, right IMAX 27.5 mL/min, left STA 29.0 mL/min, left IMAX 35.6 mL/min (Figure 1). Since STA and IMAX diameters are nearly the same, Poiseuille’s law indicates that flows depend on the pressure gradient deltaP. Figure 2 shows equivalent deltaP for the STA and IMAX.
Conclusions: STA stump and IMAX vessel diameters, deltaP, and flows are comparable. Thus, we demonstrate flow sufficiency of the STA stump versus IMAX and suggest that the STA stump is a valuable donor option in flow replacement bypass surgery for cerebral aneurysms.
Patient Care: Our study demonstrates the flow sufficiency of the STA stump, thereby avoiding the need to harvest the IMAX and reducing the complexity and morbidity of cerebral bypass surgery.
Learning Objectives: By the conclusion of this session, participants should be able to:
1) Understand the flow-carrying capacity of the STA stump and IMAX
2) Identify the advantages of the STA stump over the IMAX as a donor graft
3) Appreciate the value of the STA stump in flow replacement bypass surgery for cerebral aneurysms