Mats Cronqvist

Endovascular Treatment Using Predominantly Stent-Assisted Coil Embolization and Antiplatelet and Anticoagulation Management of Ruptured Blood Blister–Like Aneurysms

BACKGROUND AND PURPOSE: BBA is a rare type of intracranial aneurysm that is difficult to treat both surgically and endovascularly and is often associated with a high degree of morbidity/mortality. The aim of this study was to present clinical and angiographic results, as well as antiplatelet/anticoagulation regimens, of endovascular BBA treatment by using predominantly stent-assisted coil embolization. MATERIALS AND METHODS: Thirteen patients (men/women, 6/7; mean age, 49.3 years) with ruptured BBAs were included from 2 different institutions. Angiographic findings, treatment strategies, anticoagulation/antiplatelet protocols, and clinical (mRS) and angiographic outcome were retrospectively analyzed. RESULTS: Eleven BBAs were located in the supraclinoid ICA, and 2 on the basilar artery trunk. Nine of 13 were ≤3 mm in the largest diameter, and 8/13 showed early growth before treatment. Primary stent-assisted coiling was performed in 11/13 patients, double stents and PAO in 1 patient, each. Early complementary treatment was required in 3 patients, including PAO in 2. In stent-placement procedures, altered periprocedural antiplatelet (11/12) and postprocedural heparin (6/12) protocols were used without evidence of thromboembolic events. Two patients had early rehemorrhage, including 1 major fatal SAH. Twelve of 13 BBAs showed complete or progressive occlusion at late angiographic follow-up. Clinical midterm outcome was good (mRS scores, 0–2) in 12/13 patients. CONCLUSIONS: Stent-assisted coiling of ruptured BBAs is technically challenging but can be done with good midterm results. Reduced periprocedural and postprocedural antiplatelet/anticoagulation protocols may be used with a low reasonable risk of thromboembolic complications. However, regrowth/rerupture remains a problem underlining the importance of early angiographic follow-up and re-treatment, including PAO if necessary.

Nimodipine in aneurysmal subarachnoid hemorrhage: a randomized study of intravenous or peroral administration

OBJECT The calcium antagonist nimodipine has been shown to reduce the incidence of ischemic complications following aneurysmal subarachnoid hemorrhage (SAH). Although most randomized studies have been focused on the effect of the peroral administration of nimodipine, intravenous infusion is an alternative and the preferred mode of treatment in many centers. It is unknown whether the route of administration is of any importance for the clinical efficacy of the drug. METHODS One hundred six patients with acute aneurysmal SAH were randomized to receive either peroral or intravenous nimodipine treatment. The patients were monitored for at least 10 days after bleeding in terms of delayed ischemic neurological deficits (DINDs) and with daily measurements of blood flow velocities in the middle cerebral arteries by using transcranial Doppler ultrasonography. Three months after SAH, clinical outcome and new cerebral infarctions according to MR imaging studies were recorded. RESULTS Baseline characteristics (age, sex distribution, clinical status on admission, radiological findings, and aneurysm treatment) did not differ between the treatment groups. There was no significant difference in the incidence of DINDs (28 vs 30% in the peroral and intravenous groups, respectively) or middle cerebral artery blood flow velocities (> 120 cm/second, 50 vs 45%, respectively). Clinical outcome according to the Glasgow Outcome Scale was the same in both groups, and there was no difference in the number of patients with new infarctions on MR imaging. CONCLUSIONS The results suggest that there is no clinically relevant difference in efficacy between peroral and intravenous administration of nimodipine in preventing DINDs or cerebral vasospasm following SAH.

Impact of coil embolization on overall management and outcome of patients with aneurysmal subarachnoid hemorrhage

OBJECTIVE:We report on the consequences of introducing coil embolization for the total management of and outcome in patients with subarachnoid hemorrhage (SAH). METHODS:In southern Sweden, a prospective analysis of all patients with SAH of verified aneurysmal origin was conducted during the 3 years when coiling was gradually being introduced. The incidence of acute or chronic hydrocephalus, vasospasm, delayed ischemic deterioration, and outcome at 3 to 6 months after bleeding was analyzed. RESULTS:Coiling of aneurysms was used progressively more compared with clipping during the study period. The number of patients subjected to coiling was 26 (36%) of 73 patients during calendar year 1997, 43 (53%) of 81 patients in 1999, and 55 (74%) of 74 patients in 2001 (P < 0.0001). Gradually, more elderly patients were admitted during the study period. Virtually all aneurysms located in the posterior circulation were treated by coil embolization, even at the start of the study, whereas aneurysms at all other locations were progressively more likely to be treated similarly. The incidence of hydrocephalus in the acute (average for all 3 yr, 39%) or chronic (16%) phase, vasospasm as measured by Doppler sonography (33%), and delayed ischemic deterioration (29%), as well as outcome at 3 to 6 months (61% good recovery, 13% deceased), did not change significantly during the study. The main cause of unfavorable outcome was the severity of the SAH. CONCLUSION:The increasing use of coil embolization for ruptured aneurysms in the anterior circulation did not have any significant impact on the overall incidence of SAH-related complications or outcome. The main determinant for outcome after SAH is still the severity of the SAH.

Diffusion- and perfusion-weighted MRI in therapeutic neurointerventional procedures

Abstract We describe three patients in whom we used MRI, including diffusion- and perfusion-weighted imaging (DWI, PWI) in conjunction with endovascular therapy. Two had intracranial aneurysms and one an arteriovenous malformation (AVM). The aneurysms were treated by coil embolisation or detachable balloons for proximal artery occlusion; the AVM was obliterated by intranidal glue injection. All patients had transient or permanent neurological deficits after treatment. The MRI techniques and interventional procedures are described and the DWI and PWI patterns found are correlated with the clinical features. We discuss how the information gained from MRI may increase our understanding of procedure-related complications and its potential impact on our therapeutic interventions, in order to prevent or limit the clinical consequences of such events.

Initial clinical experience with a new biointegrative cement for vertebroplasty in osteoporotic vertebral fractures.

Polymethylmethacrylate, as a widely used material for vertebroplasty, has several drawbacks such as heat development and high allergenic potential. In order to avoid these drawbacks ceramic cement materials have been developed. The purpose of this study was to evaluate a new biointegrative material for vertebroplasty in osteoporotic vertebral fractures regarding pain relief, safety aspects and technical feasibility. The injectable bone substitute Cerament™ SpineSupport has been developed for vertebroplasty of osteoporotic vertebral fractures. The aim of the product is to provide mechanical stability by cured calcium sulfate dehydrate during a period of several weeks and to act as an osteo-conductive support by hydroxyl apatite particles. Inclusion criteria were a stable single vertebral fracture at levels Th5 to L5, verified by CT and MRI, and not older than four weeks, in osteoporotic patients aged 60 years or older. Bipedicular vertebroplasty technique was used. Follow up included CT directly after treatment and after two month and pain assessment (VAS) pre and post procedure after two weeks and one month. Seven patients (age range 62 – 96 years, mean 73.9, five women, two men) were treated at levels T 8 (n=1), T 12 (n=4) and L1 (n=2). The average injected volume was 1.9 ml (range 0.2 – 4 ml). No material or procedure-related complications were observed. An average height loss of the treated vertebral bodies of 3.6 mm (range 1.5 – 5.4) was seen two months after treatment as compared to pre-treatment CT. Pain assessment by VAS resulted in an improvement from mean 69 prior treatment to 37 the day post treatment, 42 after two weeks and 30 after one month. Initial results indicate that Cerament™ SpineSupport is safe and effective in the treatment of acute osteoporotic vertebral body fractures. Further studies with long-term follow-up are needed to confirm these results and to prove the concept of osteoconduction with hydroxyl apatite particles.

Evaluation of Time-of-Flight and Phase-Contrast MRA Sequences at 1.0 T for Diagnosis of Carotid Artery Disease I. A Phantom and Volunteer Study

Purpose and Material: The aim of this work was, firstly, to compare different manufacturer-provided MRA sequences in a 1.0 T MR unit, with respect to the visibility of an artificial stenosis in a flow phantom and, secondly, to evaluate the same sequences in healthy volunteers with respect to S/N ratio levels and practical in vivo implementation routines. Methods: The studied sequences were 2D and 3D TOF and sequences with an acquisition time of approximately 10 min. Quantitative signal evaluation was made using single transverse partitions in all phantom experiments. MIP angiograms and MPR reconstructions were made for visual inspection of image quality. In vivo, the images were individually evaluated by visual inspection by experienced neuroradiologists. Results: In the evaluation of the grade and length of a stenosis, a combination of MIP and MPR was seen to be the optimal and necessary procedure. A shortening of TE played an important and significant role in the visualization of the poststenotic flow in the phantom using TOF MRA. However, the shortest TE values gave poor S/N ratio in vivo. The good results achieved in the phantom studies for 3D phase-contrast were somewhat reversed in the volunteer studies, whereas 3D TOF sequences showed good results in both the phantom and the volunteer studies.

Comprehensive CT Evaluation in Acute Ischemic Stroke: Impact on Diagnosis and Treatment Decisions.

Background. With modern CT imaging a comprehensive overview of cerebral macro- and microcirculation can be obtained within minutes in acute ischemic stroke. This opens for patient stratification and individualized treatment. Methods. Four patients with acute ischemic stroke of different aetiologies and/or treatments were chosen for illustration of the comprehensive CT protocol and its value in subsequent treatment decisions. The patients were clinically evaluated according to the NIHSS-scale, examined with the comprehensive CT protocol including both CT angiography and CT perfusion, and followed up by MRI. Results. The comprehensive CT examination protocol increased the examination time but did not delay treatment initiation. In some cases CT angiography revealed the cause of stroke while CT perfusion located and graded the perfusion defect with reasonable accuracy, confirmed by follow-up MR-diffusion. In the presented cases findings of the comprehensive CT examination influenced the treatment strategy. Conclusions. The comprehensive CT examination is a fast and safe method allowing accurate diagnosis and making way for individualized treatment in acute ischemic stroke.

Cerebral perfusion imaging in hemodynamic stroke: be aware of the pattern.

Reduction of the cerebral perfusion pressure caused by vessel occlusion or stenosis is a cause of neurological symptoms and border-zone infarctions. The aim of this article is to describe perfusion patterns in hemodynamic stroke, to give a practical approach for the assessment of colour encoded CT- and MR-perfusion maps and to demonstrate the clinical use of comprehensive imaging in the workup of patients with hemodynamic stroke. Five patients with different duration cause and degree of hemodynamic stroke were selected. The patients shared the typical presentation with fluctuating and transient symptoms. All were examined by MR or CT angiography and MR or CT perfusion in the symptomatic phase. All patients were examined with diffusion weighted imaging. All five cases showed the altered perfusion patterns of hemodynamic insufficiency with a slight or marked increase in CBV in the supply area of the affected vessel and only slightly reduced or maintained CBF. The perfusion disturbances were most easily detected on the MTT maps. Border-zone infarctions were seen in all cases. The typical pattern for hemodynamic insufficiency is characterized by increased CBV, normal or decreased CBF and prolonged MTT in the affected areas. The increased CBV is the hallmark of stressed autoregulation. Reading the color-encoded perfusion maps enables a quick and robust assessment of the cerebral perfusion and its characteristic patterns. Internal border-zone infarctions can be regarded as a marker for hemodynamic insufficiency. Finding of the typical rosary-like pattern of DWI lesions should call for further work up.