Short-term arteriographic and clinical outcome after cerebral angioplasty and stenting for intracranial vertebrobasilar and carotid atherosclerotic occlusive disease.

BACKGROUND AND PURPOSE: The safe performance of percutaneous transluminal cerebral angioplasty for intracranial atherosclerotic lesions requires that the risk of complications, such as acute occlusion or symptomatic dissection, and restenosis be reduced. Our purpose was to assess the effectiveness, safety, and short-term arteriographic and clinical outcome of cerebral angioplasty and stenting (CAS) for intracranial vertebrobasilar and distal internal carotid atherosclerotic occlusive lesions. METHODS: Between March 1998 and November 1998, 10 patients with 12 intracranial atherosclerotic lesions of the vertebrobasilar artery and the distal internal carotid artery underwent treatment with flexible balloon-expandable coronary stents. RESULTS: Although in two of the 10 patients CAS was not successful because of the inability to access the site of arterial stenosis, 10 lesions in eight patients were successfully dilated with stents. No complications occurred during or after the procedure and no neurologic ischemic events or restenoses occurred during the follow-up period. CONCLUSION: CAS appears to be a safe and effective means for treating intracranial atherosclerotic occlusive disease, yielding a favorable arteriographic and clinical outcome.

[Brain oxygen extraction fraction as an indicator for shunting operation in normal pressure hydrocephalus].

It is still difficult for neurosurgeons to determine which patients with suspected idiopathic normal pressure hydrocephalus (NPH) should undergo shunting. We need to find a more accurate indicator to predict the effect of shunting. We introduced a new preoperative examination of brain oxygen extraction fraction (OEF) and examined whether preoperative OEF value is effective for prediction of the surgical results. Global brain OEF was calculated from oxygen contents of arterial blood (AO2) and jugular venous blood (VjO2) selectively sampled from the right jugular bulb using the Seldinger method: OEF = (AO2-VjO2)/AO2. Since June 1996 we have treated 9 patients suspected of idiopathic and 10 patients suspected of secondary NPH. OEF in non-NPH patients with dilated ventricle (n = 10) and in infarct patients (n = 85) were 0.33 +/- 0.02 and 0.38 +/- 0.06, respectively. In contrast, OEF increased both in idiopathic NPH (0.42 +/- 0.04) and secondary NPH (0.45 +/- 0.02), and the NPH patients with the higher preoperative OEF values showed the better symptomatic recovery. The present study suggests that brain function may be reversible when OEF can be increased and that OEF can be a useful indicator for predicting the effect of a shunting operation in NPH.

[The usefulness of dynamic computed tomography scanning in predicting the outcome of acute stroke patients].

The aim of this study was to investigate whether brain dynamic computed tomography (CT) is useful in predicting clinical outcome. Thirty patients suffering from cerebral ischemia in the territory of the middle cerebral artery (MCA) underwent dynamic CT scanning within 6 hours of stroke onset. Regions of interest (ROIs) were placed in the bilateral MCA territories and three parameters, peak value (PV), time to peak (TP), and PV divided by TP, were calculated from time-density curves (TDCs) on ROIs. After conventional treatment using pharmacological agents, the 30-day clinical outcome was evaluated on the Glasgow outcome scale. To investigate the relationship between the disease-to-contralateral side ratio of each parameter's value and 30-day clinical outcome, TDCs were classified into the following four types; type 1, with TP ratio less than 1.1; type 2, with TP ratio ranging from 1.1 to 1.5 and PV/TP ratio more than 0.75; type 3, with TP ratio ranging from 1.1 to 1.5 and PV/TP ratio less than 0.75; and type 4, with TP ratio more than 1.5 and PV/TP ratio less than 0.3. Clinical outcome in patients with type 1 or 2 TDC was better than in patients with type 3 or 4 TDC (p < 0.01, Fisher's exact test). We can conclude that dynamic CT is a useful means for estimating the clinical prognosis of acute stroke patients after conventional treatment. Poor clinical outcome following conventional therapy is expected in patients with type 3 or 4 TDC in contrast to patients with type 1 or 2 TDC.

Stenting treatment for intra- and extra-cranial atherosclerotic diseases.

The purpose of this study was to investigate the effect, safety and short-term outcome of stenting treatment for extra- and intra-cranial atherosclerotic diseases. Forty-one patients underwent stenting treatment using coronary and biliary stents. Eleven patients had tubular or diffuse high-grade stenoses not amenable to standard balloon angioplasty involving intra-cranial arteries, while in thirty, extra-cranial arteries were involved. Stents were successfully implanted in 36 out of 41 lesions (88%) with 2% (1/41) of overall procedural morbidity rate. Procedural and clinical success rate of intra-cranial stent placement was 64% (7/11) and no complications occurred during or after intra-cranial stent placement: the morbidity rate was 0%. Hyperperfusion injury occurred in two patients after successful implantation of stents in subtotal occlusion of the internal carotid artery, and consequently the overall clinical success rate was 80% (33/41). Restenosis occurred in four (12%) out of 33 patients who underwent six month follow-up arteriography. No ischemic attacks or stent-deformation occurred during follow-up after stenting treatment. For lesions not amenable to standard balloon angioplasty, endovascular stent placement seems to be a safe and effective treatment of modality.

Semiquantitative dynamic computed tomography to predict response to anti-platelet therapy in acute cerebral infarction.

We investigated whether dynamic computed tomography (CT) in patients with acute cerebral infarction could identify patients likely to respond to anti-platelet therapy. Seventy patients underwent semiquantitative dynamic CT within 6 h as well as cerebral angiography. All then received anti-platelet therapy with a thromboxane A2 synthetase inhibitor. Peak value (pv) and time-to-peak (tp) (time-density curves) for the Sylvian fissure were extracted from dynamic CT data and standardizing interpatient data, two indices, PV/TP index and TP index, were prepared following a standard semiquantitative manner. Both PV/TP index and TP index were effective in discriminating between 48 responders (modified Rankin scale (mRS): 0 to 2) and 22 non-responders (mRS: 3 to 5, or death: 6; both P<0.0001). High PV/TP index (>or=0.8) was a strong indicator of favorable response. Most of these patients maintained regional cerebral blood flow (rCBF) via anterograde flow or collaterals, with a TP index 1.1) and non-compensated rCBF. Intermediate PV/TP values could not predict outcome. Dynamic CT prior to therapy can identify patients with acute cerebral infarction who are treatable with anti-platelet therapy alone.