Cerebral hemodynamic disturbance in dural arteriovenous fistula with retrograde leptomeningeal venous drainage: a prospective study using 123I-iodoamphetamine single photon emission computed tomography

Abstract

abbreviatioNs ACR = affected-to-contralateral side asymmetry ratio; CBF = cerebral blood flow; CVR = cerebral vascular reactivity; dAVF = dural arteriovenous fistula; DSA = digital subtraction angiography; DTARG = dual-table autoradiographic; HIA = high-intensity area; IMP = iodoamphetamine; QSPECT = quantitative SPECT; rCBF = regional CBF; RLVD = retrograde leptomeningeal venous drainage; ROI = region of interest; SPECT = single photon emission computed tomography; TAE = transarterial embolization; TVE = transvenous embolization. obJect The severity of cerebral hemodynamic disturbance caused by retrograde leptomeningeal venous drainage (RLVD) of a dural arteriovenous fistula (dAVF) is related to neurological morbidity and unfavorable outcome. However, the cerebral hemodynamics of this disorder have not been elucidated well. The aim of this study was to assess the relationship between the cerebral venous congestive encephalopathy represented as a high-intensity area (HIA) on T2-weighted MR images and the cerebral hemodynamics examined by 123 I-iodoamphetamine (IMP) single photon emission computed tomography (SPECT), as well as the predictive value of 123 I-IMP SPECT for the development and reversibility of venous congestion encephalopathy. methods Based on the pre- and posttreatment T2 HIAs associated with venous congestion encephalopathy, patients were divided into 3 groups: a normal group, an edema group, and an infarction group. The regional cerebral blood flow (rCBF) at the region with RLVD was analyzed by 123 I-IMP SPECT, and the results were compared among the groups. results There were 11, 6, and 3 patients in the normal, edema, and infarction groups, respectively. No patients in the normal group showed any symptoms related to venous congestion. In contrast, all patients in the edema and infarction groups developed neurological symptoms. The rCBF in the edema group was significantly lower than that in the normal group, and significantly higher than that in the infarction group. The cerebral vascular reactivity (CVR) of the infarction group was significantly lower than that of the normal and edema groups. After treatment, the neurological signs disappeared in the edema group, but only partial improvement was seen in the infarction group. The rCBF also significantly increased in the normal and edema groups, but not in the infarction group. coNclusioNs Quantitative rCBF measurement is useful for evaluating hemodynamic disturbance in dAVF with RLVD. The reduction of rCBF was strongly correlated with the severity of venous congestive encephalopathy, and loss of CVR is a reliable indicator of irreversible venous infarction caused by RLVD.

Lateralized Periodic Discharges in a Patient With Dural Arteriovenous Fistula: SPECT and DWI Studies Suggest They are Ictal

“…Indeed, SPECT studies have been done in patients with dAVF; however, all of them have reported hypoperfusion. 9,10…”

Relative signal intensity on time-of-flight magnetic resonance angiography as a novel indicator of aggressive presentation of intracranial dural arteriovenous fistulas

“…7,8 The present results, a high rSI of the veins with CVR was strongly correlated with aggressive DAVF behavior, may indirectly reflect the fact that severe venous hypertension causes cerebral hemodynamic and metabolic disturbances. [7][8][9]19 Intracranial DAVFs with CVR have been associated with a high incidence of serious adverse events and poor outcomes. 6 However, in recent years, lower adverse event rates have been reported for asymptomatic DAVFs with CVR, 5,20 and symptomatic CVR has been considered an important factor for severe neurological events.…”

“…Some studies have evaluated cerebral hemodynamics and cerebral metabolism in patients with intracranial DAVFs with CVR using positron emission tomography, single photon emission computed tomography, perfusion MRI, arterial spin labeling perfusion imaging, and MR spectroscopy. [7][8][9][10][11]19,25 These reports have indicated that accompanying CVR can lead to reduced regional cerebral blood flow, increased cerebral blood volume, elevated regional oxygen extraction fraction, and impaired cerebral circulation and metabolism. [9][10][11]19 Therefore, imaging follow-up with several modalities is essential for identifying the changes associated with aggressive DAVF behavior.…”

“…7,8 The present results, a high rSI of the veins with CVR was strongly correlated with aggressive DAVF behavior, may indirectly reflect the fact that severe venous hypertension causes cerebral hemodynamic and metabolic disturbances. 7–9,19…”

“…[1][2][3][4][5][6] As CVR is closely related to cerebral hemodynamic and metabolic disturbance in DAVF and blood volume increases in the cerebral hemisphere with CVR in DAVF, 7,8 it has been suggested that angiographic findings of retrograde venous drainage into the cortical veins and delayed parenchymal circulation are important predictors of the hemodynamic status of intracranial DAVFs. [9][10][11][12] Therefore, the greater the extent of reflux into the cortical veins, the more severe is the impairment of the cerebral venous drainage. The severity and development of aggressive presentation could be predicted by estimating the degree of retrograde venous reflux in patients with DAVFs.…”