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Background and Purpose— We hypothesized that for the prediction or exclusion of aortic thrombi or plaques ≥4 mm, the combination of intima-media thickness (IMT) and distensibility (DC) of the common carotid arteries would be superior to the measurement of IMT alone. Methods— We prospectively included 208 stroke patients (mean age, 60 years) undergoing transesophageal echocardiography for screening of aortic plaques. IMT and DC were determined by ultrasound, and DC was quantified by measuring blood pressure and the common carotid arteries diameter change on M-mode ultrasound during the cardiac cycle. Results— Negative predictive values of IMT −3 /kPa for the exclusion of aortic atheroma ≥4 mm were similar (92.0% and 91.7%, respectively). However, negative predictive values increased to 98.2% and to 100.0% for the exclusion of aortic thrombi when both parameters were combined. Positive predictive values of IMT ≥0.9 mm and DC Conclusions— Our findings suggest that IMT and DC represent different vessel wall properties and that measuring both parameters provides optimized characterization of carotid atherosclerosis. Combining IMT and DC increases the predictive power of carotid ultrasound, making transesophageal echocardiography dispensable for assessment of the aorta for those with normal carotid arteries and indispensable for those patients with carotid atherosclerosis.

This study investigated (a) the hypothesis that stroke patients with aortic atheroma would show comparable atherosclerotic changes in the carotid arteries, which are easily accessible for ultrasound evaluation and (b) the possibility of carotid duplex sonography as a replacement for transoesophageal echocardiography (TEE) for the exclusion or prediction of relevant aortic plaques.In 301 consecutive patients (mean age 62 years) with acute cerebral ischaemia, two dimensional ultrasound measurements were taken of common carotid artery intima media thickness (IMT) and maximal plaque area (PA) and the local degree of internal carotid artery (ICA) stenosis were determined. Maximal aortic wall thickness (AWT) was assessed by TEE.An IMTor =0.9 mm yielded a negative predictive value (NPV) of 95.8% for exclusion of aortic atheromasor =4 mm and an NPV of 100% for the exclusion of aortic thrombi. However, positive predictive value of IMT0.9 mm was low (29.6%), increasing only slightly in the presence of carotid plaques (33%). Incidence of aortic thrombi was significantly higher withor =50% compared with50% ICA stenosis (11.3% v 3.9%, respectively). IMT and PA correlated moderately with AWT (r = 0.47, r = 0.53, respectively; p0.001). Systolic blood pressure, coronary heart disease and peripheral artery disease, increased IMT, and ICA stenosisor =50% were independently related to AWTor =4 mm.A high NPV of normal carotid ultrasound does not support routine TEE for the exclusion of complex aortic plaques as a high risk source of cerebral embolism. However, in patients with carotid atherosclerosis, particularly in those with ICA stenosisor =50%, TEE should be performed to exclude an additional high risk source for stroke.

Background and Purpose— This study investigates dynamic cerebral autoregulation assessed from spontaneous blood pressure (ABP) and cerebral blood flow velocity (CBFV) fluctuations and its time course in acute ischemic stroke. Methods— Forty patients admitted with acute ischemic stroke in the territory of the middle cerebral artery (MCA) were enrolled. Admission National Institutes of Health Stroke score was 6±4. Study 1 was performed within 22 (±11) hours and study 2 was performed within 134 (±25) hours of ictus. The final analysis comprised 33 and 29 patients for study 1 and study 2, respectively. Twenty-five age- and sex-matched controls were studied. ABP (Finapres method) and CBFV in both MCAs (transcranial Doppler) were recorded over 10 minutes. Correlations between diastolic and mean ABP and CBFV fluctuations were averaged, yielding the correlation coefficient indices (Dx, Mx). Transfer function analysis was applied to obtain phase shift and gain between ABP and CBFV oscillations. Results— No disturbance of autoregulation was indicated by all parameters at study 1. Separate analyses for clinical severity, stroke side, and size did not reveal significant differences for the various autoregulatory indices at study 1 and 2. At study 2, MCA flow velocity was significantly increased on both sides, the autoregulation index Mx was slightly but significantly ( P Conclusions— Dynamic cerebral autoregulation assessed from spontaneous blood pressure fluctuations does not seem to be relevantly disturbed in early minor MCA stroke. At the subacute stage, slight autoregulatory disturbance may be present.

Background and Purpose— Analysis of dynamic cerebral autoregulation (DCA) from spontaneous blood pressure fluctuations might contribute to prognosis of severe internal carotid artery stenosis, but its response to carotid recanalization has not been investigated so far. This study investigates the effect of carotid endarterectomy or stenting on various DCA parameters. Methods— In 58 patients with severe unilateral stenosis undergoing carotid endarterectomy (n=41) or stenting (n=17), cerebral blood flow velocity (CBFV, transcranial Doppler) and arterial blood pressure (ABP, Finapres method) were recorded over 10 minutes before and on average 3 days after carotid recanalization. Nineteen patients were additionally examined after 7 months. Correlations between diastolic and mean ABP and CBFV fluctuations were averaged to form the correlation coefficient indices (diastolic [Dx] and mean values [Mx]). Transfer function parameters (low-frequency phase and high-frequency gain between ABP and CBFV oscillations) were calculated over the same 10 minutes. CO 2 reactivity was assessed via inhalation of 7% CO 2 . Results— Before recanalization, all DCA parameters were clearly impaired ipsilaterally compared with contralateral sides. Phase, Dx, and Mx indicated early normalization of DCA after both endarterectomy and stenting. By multiple regression, the degree of DCA improvement was highly significantly related to the extent of impairment before recanalization. No significant change in DCA was found at follow-up. Ipsilateral gain and CO 2 reactivity increased significantly less after endarterectomy than after stenting ( P Conclusions— Dynamic cerebral dysautoregulation in patients with severe carotid obstruction is readily and completely remedied by carotid recanalization.

OBJECTIVE: To evaluate findings for patients with carotid cavernous fistulae or dural arteriovenous fistuiae (AVFs) who underwent transvenous embolization via different transvenous approaches. METHODS: Retrospective analysis of data for 31 patients (age range, 17-81 yr; mean age, 59.3 yr) with carotid cavernous fistulae (n = 6) or dural AVFs [cavernous sinus [CS], n = 11; transverse/sigmoid sinus, n = 14) was performed. The AVFs were treated with coils via different transvenous approaches, in 56 procedures. Doppler ultrasonography and time-resolved, two-dimensional, magnetic resonance projection angiography were performed to confirm the treatment. The mean clinical follow-up period was 32.5 months. RESULTS: A total of 34 transvenous procedures were performed for 17 AVFs of the CS. Eleven patients with AVFs of the CS (63%) were cured with respect to clinical symptoms, and six patients experienced improvement (37%). The approach via the internal jugular vein and inferior petrosai sinus (n = 15) was possible in 60% of cases, with complete occiusion of the fistula in 78% of cases. With the approach via the facial vein (n = 8), there was a 50% success rate. The superior ophthaimic vein approach (n = 5) was associated with a high rate of technical success (100%), with a rate of complete fistula occlusion of 80%. We encountered complications, with transient morbidity, in four cases (23.5%). For 14 dural AVFs of the transverse/sigmoid sinus, 22 transvenous procedures were performed; 12 patients were cured (85.7%) and 2 experienced improvement (14.3%). The technical success rate was 86%, with complete occlusion in 42% of cases. Minor complications occurred in six cases (42.9%) but did not lead to permanent morbidity. CONCLUSION: Transvenous treatment of CS and transverse/sigmoid sinus AVFs can be effective if all transvenous approaches, including combined surgical/endovascular approaches, are considered.

Background and Purpose— Estimation of dynamic cerebral autoregulation from spontaneous fluctuations of arterial blood pressure (ABP) and cerebral blood flow velocity (CBFV) is an attractive monitoring option for cerebral hemodynamic impairment. We evaluated the correlation coefficient index method in patients with severe obstructive carotid disease and compared it with transfer function analysis (frequency domain approach to cerebral autoregulation) and CO 2 vasomotor reactivity. Methods— In 139 patients with severe unilateral carotid stenosis (≥70%) or occlusion, CBFV (transcranial Doppler) and ABP (Finapres method) were recorded over 10 minutes. Correlations between systolic pressure, diastolic pressure, and mean ABP and CBFV oscillations over 1-minute epochs were averaged over 10 minutes to form the correlation coefficient indexes (Sx, Dx, Mx, respectively). Transfer function parameters (phase shift and gain between ABP and CBFV oscillations) were determined from the entire 10-minute period. CO 2 reactivity was assessed by inhalation of 7% CO 2 . Results— The correlation indexes Dx and Mx were significantly higher ipsilateral to stenosis and increased with degree of stenosis, indicating increasing dependence of CBFV on ABP and thus impairment of cerebral autoregulation. Dx and Mx correlated moderately but highly significantly with transfer function parameters and CO 2 reactivity and showed a good level of agreement in detecting pathological values. Patients with a small variance of the 1-minute source correlations of Dx and Mx showed clearly better correlation values. Transfer function parameters and CO 2 reactivity but not Dx and Mx were significantly poorer in patients with symptomatic stenosis or occlusion. Conclusions— The potential of the correlation coefficient indexes Dx and Mx in detecting hemodynamic impairment in patients with carotid stenosis is comparable to that of transfer function analysis and CO 2 reactivity testing. In future, a combination of various hemodynamic tests might help to identify patients at risk for ischemic events.

Eclampsia is frequently associated with brain edema, cerebral infarction or hemorrhage. Its underlying cerebrovascular pathophysiology is still poorly understood. We examined cerebral autoregulation by a non-invasive multimodal assessment in a 28-year-old primaparous woman with postpartal eclampsia. Transcranial Doppler sonography showed considerably increased cerebral blood flow velocity (CBFV) of all basal cerebral vessels. Magnetic resonance imaging demonstrated multifocal vasogenic brain edema. Using transfer function analysis, a severely decreased phase shift between respiratory-induced 0.1-Hz oscillations of arterial blood pressure and CBFV was observed, indicating substantial disturbance of dynamic cerebral autoregulation (DCA). In contrast, CO2-vasomotor reactivity of the right middle cerebral artery was only slightly reduced. We therefore assume that the cerebral arteriolar dysfunction in eclampsia leads primarily to an impairment of the autoregulatory mechanism that is followed by different degrees of arteriolar vasodilation. Because of its probably high sensitivity to hemodynamic disturbances, assessment of DCA might be of great value in early pre-eclampsia for risk prediction of cerebral arteriopathy and eclampsia. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.

Background: Amplitude responsiveness of cerebral blood flow velocity (CBFV) to CO2 is an established test of cerebrovascular reserve capacity. We aimed to analyze the time course of CBFV during CO2 reactivity testing in patients with severe carotid stenosis. Methods: 87 patients were assigned to three different groups according to the degree of stenosis (A 75–89%, B 90–94%, C 95–100%) and CBFV dynamics was assessed by transcranial Doppler sonography during hypercapnia induced by inhalation of 7% CO2. Time constants for the duration of CBFV and the end-tidal CO2 partial pressure (PetCO2) increase and decrease were calculated. In addition, time delays between subsequent changes of PetCO2 and CBFV during on- and offset of hypercapnia were determined. Results: There was a significant reduction of conventional CO2 reactivity on the side ipsilateral to the stenosis in all groups. Time constants of CBFV showed no major differences between ipsi- and contralateral sides or between different groups. The off delay between the decrease in PetCO2 and the consequent decrease in CBFV was the only out of 6 different dynamic parameters which significantly differentiated critical stenosis and occlusion from severe stenosis. Retest variability showed a highly significant correlation. Conclusions: Analysis of the dynamic CBFV response during the applied CO2 inhalation protocol revealed a significant and reproducible delay parameter which has power to detect cerebral hemodynamic compromise in patients with carotid artery stenosis similar to the conventional CO2 reactivity parameter.

Giant cell arteritis (GCA) is known to affect the extracranial part of the vertebral arteries. Bilateral vertebral artery occlusion (BVAO) is a rare but serious neurologic condition. We report 3 patients with autopsy-proven (2 patients) or clinically diagnosed (1 patient) GCA causing BVAO. A review of the literature concerning BVAO revealed 5 other cases of BVAO resulting from GCA and 110 cases with underlying arteriosclerotic disease. Our 3 patients (mean age, 66 yr; range, 60-78 yr) with BVAO resulting from GCA all had initial severe headache followed by the onset of stepwise progressive, partly side-alternating neurologic deficits due to bilateral infarctions in the vertebrobasilar circulation territory. This course, more accelerated in BVAO due to GCA than in BVAO of arteriosclerotic origin, seems to be a typical, if not particular, clinical syndrome. BVAO was the first clinical manifestation of GCA in 1 of our patients and in 1 published case. From a clinical view, BVAO resulting from GCA differs from BVAO of arteriosclerotic origin by the much higher mortality rate (75% versus 19%, respectively), the presence of headache (100% versus 22%), fever (50% versus 0%), and elevated erythrocyte sedimentation rate (ESR in all GCA cases >45 mm/h; no data in the arteriosclerotic patient group), but not by the neurologic signs themselves. Therapy of BVAO resulting from GCA is purely empiric. In view of the serious prognosis, we propose treatment with intravenous high-dose glucocorticoids and additional immunosuppression with cyclophosphamide; the use of anticoagulation depends on the individual patient's estimated risk-benefit profile. Although BVAO due to GCA is rare, physicians and especially rheumatologists or neurologists should be aware of this entity because of its high mortality in patients without immediate introduction of a high-dose immunosuppressive therapy. Suspicion of GCA should arise in a patient aged over 50 years with no other vascular risk factors suffering from bilateral symptoms of ischemia in the vertebrobasilar territory, with a quickly progressing stepwise course and with headache, fever, or history of myalgia. ESR and temporal artery biopsy should be performed without delay. Early diagnosis of GCA is necessary for immediate initiation of intensive antiinflammatory and immunosuppressive treatment, without which progressive deterioration and systemic involvement are likely to be fatal.

Recent studies were investigated that report spontaneous oscillations of cerebral perfusion in the very low-frequency range (0.01-0.04 Hz), emphasising details of spectral estimation. The effects of different spectral estimation procedures were compared, using simulated and clinical data. It was shown that data detrending, as used in many studies, can lead to an artifactual peak in the very low-frequency region of estimated power spectra, indicating that the peak cannot be taken as evidence of physiological oscillations. A quantitative, reliable method is described that can be used to assess very low-frequency oscillations. Using the method, very low-frequency oscillations were found in ten out of 17 healthy adults measured with transcranial Doppler (average frequency, 0.021 +/- 0.007 Hz, mean +/- SD), confirming earlier findings based on visual inspection of data.

In three patients with acute occlusion of the basilar artery intra-arterial fibrinolysis resulted in only partial recanalization and revealed severe stenosis as the underlying cause. Application of micro-stents without previous dilatation resulted in vessel re-opening. Two patients had an excellent clinical outcome. One patient died 10 days after the stroke due to brainstem infarction. Emergency primary stent application may improve the outcome in acute basilar artery occlusion, if intra-arterial thrombolysis fails to re-establish a sufficient flow.

In our paper we discuss the political aesthetics of Jacques Rancière, specially his writings on the documentaries of the French director Chris Marker. In a first section we give an introduction to Rancière’s political philosophy, which explains political acts in terms of seizing the word by those who have no share in our societies. Such a seizing of words reconfigures the discursive regimes that decide who can say what and under what conditions publicly. In a second section we will show how Rancière’s aesthetical writings discuss works of art in a similar way as agents of a transfiguration of orders of visibility or sight. This becomes clear, as our third section will argue, in Rancière’s film aesthetics, especially in his essays on Chris Marker. Markers movies (for instance Le Tombeau d'Alexandre) focus on and at the same time complicate the boundaries between documentary and fiction; they allow us to understand a reality which is supposedly without alternatives as a result of human practice which always can be changed.

Arterial blood pressure (ABP) shows polyphasic changes during the Mueller manoeuvre (voluntary negative intrathoracic pressure). The aim of the present study was to investigate (1) whether these changes could lie applied to detect impaired dynamic cerebral autoregulation (dCA) in carotid stenosis and (2) whether the degree of indicated impairment correlates with transfer function phase as another current measure for dCA (deep breathing method) and CO 2 -reactivity. We examined 13 patients with severe unilateral carotid artery stenosis and 16 age-matched controls during 15-s Mueller manoeuvres (MM) at -30 mmHg using bilateral transcranial Doppler sonography and non-invasive ABP recordings (Finapres, 2300, Ohmeda, Englewood, CO, USA). After an initial biphasic oscillation, cerebral blood flow velocity (CBFV) and ABP decreased to below baseline. CBFV reincreased in controls and on contralateral sides in patients 6.0 s (3.8-9.5 s, median and range) after the onset of the decrease, despite a further fall in ABP. CBFV over the affected side revealed a significantly delayed reincrease (8.0 (5.6-10.3) s; P

Voluntary negative intra-thoracic pressure (Mueller manoeuvre) is known to reduce arterial blood pressure (ABP). To investigate changes in cerebral blood flow velocity (CBFV) during 15 s Mueller manoeuvres at -30 mmHg intra-thoracic pressure, 27 young (aged 21-31 years, group A) and 11 older (52-64 years, group B) healthy adults were studied using transcranial Doppler and non-invasive ABP measurement (Finapres). After closely following the initial ABP drop, CBFV showed an overshoot during temporary recovery of ABP. Then ABP and CBFV decreased significantly to below baseline. While ABP declined further until the end of the manoeuvre, CBFV increased in group A 4.7 s (2.4-8.5) (median and range) and in group B 5.7 s (4. 1-7.2) after the onset of the CBFV decrease. Critical closing pressure (CCP), calculated for each cardiac cycle from the dynamic pressure-flow relationship (DPFR), indicated a reduction of intra-cranial pressure during the first half of the strain. DPFR-related estimation of cerebrovascular resistance provided a more physiological response than the conventional cerebrovascular resistance quotient ABP/CBFV, and decreased about 1.5 s before the observed CBFV increase. A modification of the previously described dynamic auto-regulation index ROR correlated significantly with CO2 reactivity values (r=0.61, P=0.001). In conclusion, changes in CBFV during Mueller manoeuvres are likely to reflect dynamic cerebral auto-regulation and may provide an estimate of dynamic cerebral auto-regulation capacity. In older adults, the maximal dynamic auto-regulatory response seems to be unchanged, but the onset of reaction is slightly delayed.

Background: The anterior communicating artery is a key collateral pathway in patients with internal carotid artery (ICA) occlusions. Diagnostic balloon or manual occlusion of the ICA is a qualified test for the collateral function of the circle of Willis. The aim of our study was to test whether transcranial Doppler sonography (TCD) with manual carotid compression is able to predict the degree of cross-over flow and tolerance of ICA occlusion. Methods: A prospective study was performed on 88 patients suffering from neck tumors or inoperable ICA aneurysms with planned ligation or permanent balloon occlusion of the ICA. Preceding a balloon occlusion lasting 20 min we performed TCD with manual carotid compression test. Insufficient cross-over flow during transient carotid occlusion was defined angiographically as missing opacification of the middle cerebral artery (MCA) after selective injection of contrast media in the contralateral ICA, and sonographically as a decrease greater than 60% in flow velocity of the MCA ipsilateral to the carotid occlusion. Results: TCD and angiography could be compared in 70 of 88 patients. Angiography showed no or insufficient collateral flow in 26%. All patients (n = 10) with a decrease in MCA velocity greater than 60% on angiography showed missing or poor cross-over flow. A greater than 50% increase in the anterior cerebral artery (ACA) predicted moderate or good cross-over flow in 98%. Clinical observation revealed 11 transient neurological deficits. Eight of them showed insufficient cross-over flow angiographically and sonographically. In 2 of 11 only TCD revealed such low collateral supply. Neither technique predicted hemodynamic ischemia in only 1 of the 11. Conclusion: TCD with carotid compression test is a valid method for predicting interhemispheric flow and clinically relevant hemodynamic compromise in cases of occlusion of the ICA.

In occlusive cerebrovascular disease cerebral blood flow (CBF) autoregulation can be impaired and constant CBF during fluctuations in blood pressure (BP) cannot be guaranteed. Therefore, an assessment of cerebral autoregulation should consider not only responsiveness to CO2 or Diamox. Passive tilting (PT) and Valsalva maneuver (VM) are established tests for cardiovascular autoregulatory function by provoking BP changes. To develop a comprehensive test for vasomotor reactivity with a potential increase of sensitivity and specificity, the authors combined these maneuvers. Blood pressure, corrected to represent arterial pressure at the level of the circle of Willis, middle cerebral artery Doppler frequencies (DF), heart rate (HR) and endtidal partial pressure of CO2 (PtCO2) were measured continuously and noninvasively in 81 healthy subjects (19-74 years). Passive tilt and Valsalva maneuver were performed under normocapnia (mean, 39 + 4 mmHg CO2) and under hypercapnia (mean, 51 + 5 mm Hg CO2). Resting BP, HR, and DF increased significantly under hypercapnia. Under normocapnia and hypercapnia, PT induced only minor, nonsignificant changes in mean BP at the level of the circle of Willis compared to baseline (normocapnia: + 2 + 15 mm Hg; hypercapnia: -3 +/- 13 mm Hg). This corresponded with a nonsignificant decrease of the mean of DF (normocapnia: -4 +/- 11%; hypercapnia -6 +/- 12%). Orthostasis reduced pulsatility of BP by a predominantly diastolic increase of BP without significant changes in pulsatility of DF. Valsalva maneuver, with its characteristic rapid changes of BP due to elevated intrathoracic pressure, showed no significant BP differences in changes to baseline between normocapnic and hypercapnic conditions. Under both conditions the decrease in BP in phase II was accompanied by significantly increased pulsatility index ratio (PIDF/PIBP). Valsalva maneuver and PT as established tests in autonomic control of circulation provoked not only changes in time-mean of BP but also in pulsatility of BP. The significant increase in pulsatility ratio and decrease of the DF/BP ratio during normocapnia and hypercapnia indicated preserved CBF autoregulation within a wide range of CO2 partial pressures. Hypercapnia did not significantly influence the autoregulatory indices during VM and PT. Physiologically submaximally dilated cerebral arterioles can guarantee unchanged dynamics of cerebral autoregulation. Combined BP and MCA-DF assessment under hypercapnia enables investigating the effect of rapid changes of blood pressure on CO2-induced predilated cerebral arterioles. Assuming no interference of hypercapnia-induced vasodilation, VM, with its rapid, distinct changes in BP, seems especially to be adequate provocation for CBF autoregulation. This combined vasomotor reactivity might provide a more sensitive diagnostic tool to detect impaired cerebral autoregulation very early.

Background and Purpose —Responsiveness to CO 2 is an established test of cerebrovascular reserve capacity. Arterial partial pressure of CO 2 (P co 2 ) and arterial blood pressure (BP) are key parameters for cerebral blood flow. To investigate the interaction between P co 2 and BP, we performed a study with simultaneous measurement of CO 2 and BP during CO 2 reactivity testing with transcranial Doppler sonography. Methods —Eighty-one healthy volunteers, aged 19 to 74 years, underwent examination defined by a protocol with multimodality monitoring of BP, heart rate (HR), P co 2 , and Doppler frequencies (DFs) of the left middle cerebral artery (MCA). Reproducibility was tested in a subgroup of 14 volunteers ≥65 years of age by CO 2 reactivity testing on different days. Results —Increase of P co 2 was accompanied by a parallel increase of mean±SD time values of DF (3.6±1.6%/mm Hg CO 2 ). BP levels were significantly elevated after 60-second hypercapnia (mean values, 0.5±0.55 mm Hg/mm Hg CO 2 ). A significant decrease over time was seen only for pulsatility in DF but not in BP. Analysis of variance and covariance with repeated measures revealed a highly significant effect of CO 2 on MCA Doppler shift. A less-pronounced effect on DF was seen for BP. Correlation analysis showed no significance for CO 2 reactivity, but a significant correlation between test and retest was seen in BP-related CO 2 reactivity. Conclusions —The CO 2 response curve showed the known linear increase of DF. The parallel significant increase in BP most likely results from activation of the central sympathetic nervous system. The poor reproducibility for Doppler CO 2 reactivity is to some extent explainable by variability of BP. CO 2 -induced increases in BP can have relevant influence on MCA Doppler shift and lead to misinterpretation of Doppler CO 2 test results.

Sirs: Spinal subarachnoid hemorrhage (SAH) acounts for less than 1% of SAHs. Cerebral complications are uncommon and moderate in severity. We report on a 30year old woman suffering from severe cerebral vasospasms, without subarachnoid blood in successive cranial CT scans, due to spinal SAH caused by a ruptured solitary spinal aneurysm of unknown etiology. The patient suffered from a graft-versus-host reaction of her transplanted kidney. Under immunosuppression, she developed recurrent pneumonias and a septicemia with unknown germ that were treated by intravenous antibiotics. In the further course, she suddenly presented with headache, back pain and progressive behavioural disturbances. Cranial CT at this time was normal. Three lumbar punctures revealed a hemorrhagic CSF that was considered to be artificially bloody. Because of increasing paraparesis and rectal incontinence, the patient was referred to our clinic one week later. On admission, she was in poor clinical condition with reduced consciousness, no speech production, nuchal rigidity and paraplegia lasting for more than 24 hours. Cranial CT was normal, whereas cranial MRI showed bilateral MCA-infarction on diffusionweighted MRI (Fig. 1A). Spinal MRI revealed a ventrally located intraspinal circular tumour at the level of the twelfth thoracic vertebra with an intradural T1-hyperintensive signal in the thoracolumbar canal (Fig. 1B). Suboccipital puncture yielded a hemorrhagic CSF (2540 cells per ll). Conventional panangiography revealed a solitary aneurysm (8 · 15 mm) originating from the descending branch of the anterior spinal artery at the level of the twelfth thoracic vertebra (Fig. 1C) as well as generalised, severe cerebral vasospasms. Despite immediate triple-Hand nimodipine-therapy, CT 12h later demonstrated large bilateral MCAinfarction, but was still without any cerebral SAH (Fig. 1D). Because of the infavorable prognosis, palliative treatment was carried out until death due to a pneumogenic sepsis 23 days later. To date, 20 cases of spinal SAH due to a rupture of isolated spinal aneurysms have been reported [1–2, 4–16]. Of the eight reported patients with thoracolumbar aneurysms, all had an acute onset of pain in the thoracolumbar region [1, 8, 11, 13, 15]. Three also had paraparesis [1, 8]. Six of the eight patients were treated surgically [8, 11, 13, 15] whilst the other two had a conservative treatment [1]. All patients recovered either without or with minor neurological deficits. The authors found two dissecting aneurysms [8], an inflammation within the vessel wall in two cases [1, 11] and no evident etiology in the other four reports [1, 8, 13, 15]. In our patient, general autopsy did not reveal any underlying systemic (e.g. polyarteriitis nodosa, connective tissue disorder, syphilis), cerebral or further spinal vascular pathology. Since the SAH was related in timing to systemic infection in the context of immunosuppression, the aneurysm may result from a local inflammation. Morphologically, inflammatory aneurysms are characterised by proliferation of the tunica intima and media as well as inflammatory infiltrates. Infectious agents may be detected within the vessel wall [4, 11]. However, the aneurysm in our patient only yielded a prominent fibroblastic proliferation without inflammatory infiltrates (Fig. 2). Additional analysis of blood and CSF samples did not contain any germs and all serological tests were negative. Thus the inflammatory etiology remains speculative. In summary, we present the case of a young woman who suffered from symptomatic cerebral vasospasms due to spinal SAH caused by a ruptured solitary spinal aneurysm. Pathogenesis of cerebral vasospasm is unclear, but is most probably due to a distant inflammatory response caused by the subarachnoid blood [3]. Although there have been a few R. Surges AE M. Schubert AE C. Weiller A. Hetzel AE W.-D. Niesen (&) Dept. of Neurology University Clinics of Freiburg Breisacherstr. 64 79106 Freiburg, Germany Tel.: +49-761/270-5157 Fax: +49-761/270-5328 E-Mail: wolf-dirk.niesen@uniklinikfreiburg.de

In vivo studies selectively assessing preganglionic and central autonomic nervous system activity in patients with autonomic failure have so far been limited to testing pituitary function. In animal experiments carbon dioxide (CO2) selectively stimulates central sympathetic nuclei in the ventrolateral medulla and preganglionic sympathetic neurons in the cervical trunk. This central stimulation seems to overrule less pronounced peripheral vasodilatatory effects. This study addressed the question of whether hypercapnea is a suitable challenge procedure to test preganglionic and central autonomic activity in healthy subjects and in patients with autonomic failure of preganglionic and central origin. Seven patients with multiple system atrophy (MSA) and 30 age-matched healthy volunteers underwent a protocol including a Valsalva manoeuvre (VM) under normo- and hypercapnic conditions and exposure to hypercapnea under supine resting conditions. Blood pressure (BP), heart rate (HR) and end-tidal CO2 partial pressure were measured continuously and non-invasively. In normal controls hypercapnea induced significantly higher BP values in phases II, IIe, III and IV of the VM compared to the normocapnic VM and a significant increase in BP during steady-state supine exposure compared to normocapnic baseline. HR increased significantly only after 40 s of steady-state hypercapnea during the latter challenge. In patients with MSA and autonomic failure, in whom a predominantly preganglionic lesion of the autonomic nervous system is established, no significant effects of hypercapnea on the cardiovascular parameters were found. Although this non-invasive challenge procedure cannot differentiate between pre- and postganglionic autonomic failure, exposure to hypercapnea enables the investigation of efferent autonomic activity to vasoconstrictors generated from autonomic centres in the brainstem and cervical trunk.

The objective of the present study was to identify predictors of left atrial spontaneous echocardiographic contrast (SEC) or thrombus in patients with stroke with sinus rhythm and left ventricular dysfunction. Of 500 consecutive patients with stroke, 48 with sinus rhythm and reduced left ventricular ejection fractions (EFs)or =45% were examined. Ten patients presented with SEC or thrombus. The patients with SEC or thrombus had larger left atrial diameters (47 +/- 4 vs 42 +/- 6 mm, p0.05), smaller EFs (30 +/- 9% vs 38 +/- 8%, p0.01), and slower left atrial appendage (LAA) flow velocities (42 +/- 13 vs 61 +/- 17 cm/s, p0.01). Multivariate analysis identified EFor =35% and LAA flow velocityor =55 cm/s as predictors of SEC or thrombus (p0.05). Patients with stroke with sinus rhythm and moderate- to high-grade reduction of the left ventricular EF represent a risk group for a left atrial source of embolism and should undergo transesophageal echocardiography.

To compare the impact of initial corticosteroid treatment on high-resolution MRI and colour-coded duplex sonography (CCDS) findings in patients with GCA (temporal).Sensitivity and specificity of CCDS and high-resolution contrast-enhanced MRI studies of 59 patients with suspected GCA were retrospectively analysed. Patients were grouped according to the duration of steroid treatment before imaging: 0-1 day, 2-4 days and4 days. In 41 patients, imaging results were compared with findings of temporal artery biopsy (TAB).Sixty-one per cent (36/59) of patients were diagnosed with GCA. TAB findings were positive in 59% (24/41). The compared results of TAB sensitivity of CCDS and MRI under steroid treatment of 0-1 day were 92% and 90%, 2-4 days 80% and 78% and4 days 50% and 80%, respectively. The compared results of the final clinical diagnosis sensitivity of CCDS and MRI under steroid treatment of 0-1 day was 88% and 85%, 2-4 days 50% and 64% and4 days 50% and 56%, respectively.Sensitivity of a first-time CCDS or an MRI for detection of GCA rapidly decreases under corticosteroid treatment. Therefore imaging of patients with suspected GCA should be performed as soon as possible, preferably within the first days of treatment.

The selection of patients with cervical internal carotid artery occlusion (ICAO) for extracranial-intracranial bypass surgery is based on exhausted cerebrovascular reactivity to vasodilatory stimuli. However, a spontaneous increase in this reactivity can occur with time, questioning the ideal time for bypass surgery. In contrast, the natural course of dynamic cerebral autoregulation is not known in these patients.Patients with cervical ICAO were examined at baseline and after a mean interval of 15 months. Dynamic autoregulation was determined by transcranial Doppler sonography in both middle cerebral arteries via respiratory-induced 0.1-Hz oscillations (phase, available for n=47 patients) and correlation analysis between diastolic blood pressure and Doppler signal (index Dx, n=55 patients). Pre-defined cut-off values and repeatability measures of healthy controls were used to define significant individual changes in autoregulation.Group mean comparisons between studies were not significant for any autoregulation parameter. The intraclass correlation coefficient between studies was high for phase (ipsilateral: 0.83; contralateral: 0.74), and moderate for Dx (ipsilateral: 0.63; contralateral: 0.35). There was no clear trend for an improvement across cut-off values. A significant individual improvement/deterioration in autoregulation occurred in 6%/6% for phase and 13%/9% for Dx.Dynamic autoregulation only rarely improves during the course of ICAO. This finding should be considered when deciding for or against a policy of delaying extracranial-intracranial bypass surgery for reasons of a potentially improving hemodynamic status.