Initial clinical experience with the 4-F self-expanding XPERT stent system for infrapopliteal treatment of patients with severe claudication and critical limb ischemia

PURPOSE: To evaluate the primary success and short-term patency associated with a new 4-F sheath-compatible self-expanding nitinol stent after failed conventional angioplasty of distal popliteal and infrapopliteal lesions in severe lifestyle-limiting claudication (LLC) and chronic critical limb ischemia (CLI). MATERIALS AND METHODS: Between May 2003 and July 2005, 35 patients with Rutherford category 3-5 disease (16 patients with CLI, 19 patients with LLC) underwent percutaneous transluminal angioplasty (PTA) and stent implantation. Indications for stent placement were residual stenosis, flow-limiting dissections, or elastic recoil after PTA. Before and after the intervention and during the 6-month follow-up, clinical investigation, color-flow and duplex Doppler ultrasonography, and digital subtraction angiography were performed. Technical success, primary patency at 6 months, clinical improvement as defined by Rutherford with clinical and hemodynamic measures, and complications were evaluated. RESULTS: A total of 22 patients underwent distal popliteal artery stent placement and 13 underwent tibioperoneal artery stent placement. Stent implantation was successfully performed in all patients. After stent placement, the primary cumulative patency rate for the study group at 6 months was 82%. The mean resting ankle-brachial index at baseline was 0.50 +/- 0.16 and significantly increased to 0.90 +/- 0.17 at 12-24 hours after intervention and 0.82 +/- 0.24 at latest follow-up (P < .001 for both). The sustained clinical improvement rate was 80% at the 6-month follow-up. The 6-month limb salvage rate regarding major amputation was 100%. The rate of major complications was 17%. CONCLUSIONS: Infrapopliteal application of the new nitinol stent is a safe, feasible, and effective method with good short-term patency rate in the treatment of severe LLC and chronic CLI.

Immunization of Macaca fascicularis against experimental periodontitis using a vaccine containing cysteine proteases purified from Porphyromonas gingivalis

INTRODUCTION: Periodontitis is a common infectious disease to which Porphyromonas gingivalis has been closely linked, in which the attachment tissues of the teeth and their alveolar bone housing are destroyed. We conducted a study to determine if immunization using a purified antigen could alter the onset and progression of the disease. METHODS: Using the ligature-induced model of periodontitis in Macaca fascicularis, we immunized five animals with cysteine protease purified from P. gingivalis and used an additional five animals as controls. Alveolar bone loss was measured by digital subtraction radiography. RESULTS: Immunization induced high titers of specific immunoglobuin G serum antibodies that were opsonic. Total bacterial load, levels of P. gingivalis in subgingival plaque and levels of prostaglandin E(2) in gingival crevicular fluid were significantly reduced. Onset and progression of alveolar bone loss was inhibited by approximately 50%. No manifestations of toxicity were observed. CONCLUSIONS: Immunization using a purified protein antigen from P. gingivalis inhibits alveolar bone destruction in a ligature-induced periodontitis model in M. fascicularis.

Effects of non-ionic iodinated contrast media on patient heart rate and pressures during intra-cardiac or intra-arterial injection

PURPOSE: To compare the effects on heart rate (HR), on left ventricular (LV) or arterial pressures, and the general safety of a non-ionic low-osmolar contrast medium (CM) and a non-ionic iso-osmolar CM in patients undergoing cardiac angiography (CA) or peripheral intra-arterial digital subtraction angiography (IA-DSA). MATERIALS AND METHODS: Two double-blind, randomized studies were conducted in 216 patients who underwent CA (n=120) or peripheral IA-DSA (n=96). Patients referred for CA received a low-osmolar monomeric CM (iomeprol-350, n=60) or an iso-osmolar dimeric CM (iodixanol-320; n=60). HR and LV peak systolic and end-diastolic pressures were determined before and after the first injection during left and right coronary arteriography and left ventriculography. Monitoring for all types of adverse event (AE) was performed for 24 h following the procedure. t-tests were performed to compare CM for effects on HR. Patients referred for IA-DSA received iomeprol-300 (n=49) or iodixanol-320 (n=47). HR and arterial blood pressure (BP) were evaluated before and after the first 4 injections. Monitoring for AE was performed for 4 h following the procedure. Repeated-measures ANOVA was used to compare mean HR changes across the first 4 injections, whereas changes after the first injection were compared using t-tests. RESULTS: No significant differences were noted between iomeprol and iodixanol in terms of mean changes in HR during left coronary arteriography (p=0.8), right coronary arteriography (p=0.9), and left ventriculography (p=0.8). In patients undergoing IA-DSA, no differences between CM were noted for effects on mean HR after the first injection (p=0.6) or across the first 4 injections (p=0.2). No significant differences (p>0.05) were noted in terms of effects on arterial BP in either study or on LV pressures in patients undergoing CA. Non-serious AE considered possibly CM-related (primarily headache and events affecting the cardiovascular and digestive systems) were reported more frequently by patients undergoing CA and more frequently after iodixanol (14/60 [23.3%] and 2/47 [4.3%]; CA and IA-DSA, respectively) than iomeprol (10/60 [16.7%] and 1/49 [2%], respectively). CONCLUSIONS: Iomeprol and iodixanol are safe and have equally negligible effects on HR and LV pressures or arterial BP during and after selective intra-cardiac injection and peripheral IA-DSA. CLINICAL APPLICATION: Iomeprol and iodixanol are safe and equally well tolerated with regard to cardiac rhythm and clinical preference should be based on diagnostic image quality alone.

Ultrasound diagnosis of spontaneous carotid dissection with isolated Horner syndrome

BACKGROUND AND PURPOSE: Isolated Horner syndrome without associated cranial nerve palsies or ischemic symptoms is an important presentation of spontaneous internal carotid artery dissection (sICAD). Ultrasound is often used as a screening method in these patients because cervical MRI is not always available on an emergency basis. Current knowledge on ultrasound findings in patients with sICAD presenting with isolated Horner syndrome is limited. METHODS: Patients were recruited from prospective cervical artery dissection databases of 3 tertiary care centers. Diagnosis of sICAD was confirmed by cervical MRI and MR angiography or digital subtraction angiography in all patients. Data on Doppler sonography and color duplex sonography examinations performed within 30 days of symptom onset were analyzed. RESULTS: We identified 88 patients with Horner syndrome as the only sign of sICAD. Initial ultrasound examination was performed in 72 patients after a mean time interval from symptom onset to examination of 11 (SD 8) days. The overall frequency of false-negative ultrasound findings was 31% (22 of 72 patients). It showed stenosis >or=80% or occlusion in 34 (47%) patients, and stenosis

Clinical validation of an automated vessel-segmentation software of the extracranial-carotid arteries based on 3D-MRA: A prospective study

OBJECTIVES: To determine the accuracy of automated vessel-segmentation software for vessel-diameter measurements based on three-dimensional contrast-enhanced magnetic resonance angiography (3D-MRA). METHOD: In 10 patients with high-grade carotid stenosis, automated measurements of both carotid arteries were obtained with 3D-MRA by two independent investigators and compared with manual measurements obtained by digital subtraction angiography (DSA) and 2D maximum-intensity projection (2D-MIP) based on MRA and duplex ultrasonography (US). In 42 patients undergoing carotid endarterectomy (CEA), intraoperative measurements (IOP) were compared with postoperative 3D-MRA and US. RESULTS: Mean interoperator variability was 8% for measurements by DSA and 11% by 2D-MIP, but there was no interoperator variability with the automated 3D-MRA analysis. Good correlations were found between DSA (standard of reference), manual 2D-MIP (rP=0.6) and automated 3D-MRA (rP=0.8). Excellent correlations were found between IOP, 3D-MRA (rP=0.93) and US (rP=0.83). CONCLUSION: Automated 3D-MRA-based vessel segmentation and quantification result in accurate measurements of extracerebral-vessel dimensions.

Focal laminar cortical infarcts following aneurysmal subarachnoid haemorrhage

INTRODUCTION: The aim of this prospective study was to analyse small band-like cortical infarcts after subarachnoid haemorrhage (SAH) using magnetic resonance imaging (MRI) with reference to additional digital subtraction angiography (DSA). METHODS: In a 5-year period between January 2002 and January 2007 10 out of 188 patients with aneurysmal SAH were evaluated (one patient Hunt and Hess grade I, one patient grade II, four patients grade III, two patients grade IV, and two patients grade V). The imaging protocol included serially performed MRI with diffusion- and perfusion-weighted images (DWI/PWI) at three time points after aneurysm treatment, and cerebral vasospasm (CVS) was analysed on follow-up DSA on day 7+/-3 after SAH. RESULTS: The lesions were located in the frontal lobe (n=10), in the insular cortex (n=3) and in the parietal lobe (n=1). The band-like infarcts occurred after a mean time interval of 5.8 days (range 3-10 days) and showed unexceptional adjacent thick sulcal clots. Seven out of ten patients with cortical infarcts had no or mild CVS, and in the remaining three patients DSA disclosed moderate (n=2) or severe (n=1) CVS. CONCLUSION: The infarct pattern after aneurysmal SAH includes cortical band-like lesions. In contrast to territorial infarcts or lacunar infarcts in the white matter which develop as a result of moderate or severe proximal and/or distal vasospasm visible on angiography, the cortical band-like lesions adjacent to sulcal clots may also develop without evidence of macroscopic vasospasm, implying a vasospastic reaction of the most distal superficial and intraparenchymal vessels.

Assessment of flow in perforating arteries during intracranial aneurysm surgery using intraoperative near-infrared indocyanine green videoangiography

OBJECTIVE: Perforating arteries are commonly involved during the surgical dissection and clipping of intracranial aneurysms. Occlusion of perforating arteries is responsible for ischemic infarction and poor outcome. The goal of this study is to describe the usefulness of near-infrared indocyanine green videoangiography (ICGA) for the intraoperative assessment of blood flow in perforating arteries that are visible in the surgical field during clipping of intracranial aneurysms. In addition, we analyzed the incidence of perforating vessels involved during the aneurysm surgery and the incidence of ischemic infarct caused by compromised small arteries. METHODS: Sixty patients with 64 aneurysms were surgically treated and prospectively included in this study. Intraoperative ICGA was performed using a surgical microscope (Carl Zeiss Co., Oberkochen, Germany) with integrated ICGA technology. The presence and involvement of perforating arteries were analyzed in the microsurgical field during surgical dissection and clip application. Assessment of vascular patency after clipping was also investigated. Only those small arteries that were not visible on preoperative digital subtraction angiography were considered for analysis. RESULTS: The ICGA was able to visualize flow in all patients in whom perforating vessels were found in the microscope field. Among 36 patients whose perforating vessels were visible on ICGA, 11 (30%) presented a close relation between the aneurysm and perforating arteries. In one (9%) of these 11 patients, ICGA showed occlusion of a P1 perforating artery after clip application, which led to immediate correction of the clip confirmed by immediate reestablishment of flow visible with ICGA without clinical consequences. Four patients (6.7%) presented with postoperative perforating artery infarct, three of whom had perforating arteries that were not visible or distant from the aneurysm. CONCLUSION: The involvement of perforating arteries during clip application for aneurysm occlusion is a usual finding. Intraoperative ICGA may provide visual information with regard to the patency of these small vessels.

A rare anomaly of the anterior communicating artery complex hidden by a large broad-neck aneurysm and disclosed by three-dimensional rotational angiography

Double fenestration of the anterior communicating artery (ACoA) complex associated with an aneurysm is a very rare finding and is usually caused by ACoA duplication and the presence of a median artery of the corpus callosum (MACC). We present a patient in whom double fenestration was not associated with ACoA duplication or even with MACC, representing therefore, a previously unreported anatomic variation. A 43 year old woman experienced sudden headache and the CT scans showed subarachnoid haemorrhage (SAH). On admission, her clinical condition was consistent with Hunt and Hess grade II. Conventional digital subtraction angiography (DSA) was performed and revealed multiple intracranial aneurysms arising from both middle cerebral arteries (MCA) and from the ACoA. Three-dimensional rotational angiography (3D-RA) disclosed a double fenestration of the ACoA complex which was missed by DSA. The patient underwent a classic pterional approach in order to achieve occlusion of both left MCA and ACoA aneurysms by surgical clipping. The post-operative period was uneventful. A rare anatomical variation characterised by a double fenestration not associated with ACoA duplication or MACC is described. The DSA images missed the double fenestration which was disclosed by 3D-RA, indicating the importance of 3D-RA in the diagnosis and surgical planning of intracranial aneurysms.

Determination of carbohydrate-deficient transferrin in human serum with capillary zone electrophoresis. Sample preparation strategies for the removal of interferences caused by increased levels of immunoglobulins

Capillary zone electrophoresis (CZE) in fused-silica capillaries is an effective analytical approach for the separation and determination of the transferrin (Tf) isoforms and thus carbohydrate-deficient transferrin (CDT) in human serum. Sera of patients with progressed liver cirrhosis are prone to interferences in the beta region which prevent the proper determination of CDT by CZE without additional sample preparation. Efforts to identify, reduce or even eliminate these interferences have been undertaken. Data obtained by ultrafiltration, affinity subtraction procedures using protein A, protein L and antibodies against immunoglobulins or Tf, and immunopurification of Tf suggest that the interferences in the patient sera are caused by increased levels of IgA and IgM and are best eliminated by immunopurification. Avian IgY antibody spin column immunocapture of serum Tf followed by CZE analysis of the stripped and concentrated fraction is shown to provide an attractive approach for CDT monitoring in sera with beta region interferences.

[Cerebral vasculitis]

Cerebral vasculitis is a rare disease with a potentially harmful or even fatal outcome that often affects young adults. Primary autoimmune mediated disease can be distinguished from secondary vasculitis associated to infectious disorders, connective tissue diseases, malignancies or toxic drug effects. Pathomechanisms lead to destruction of the vessel wall and consecutive hemorrhagic or ischemic brain lesions. Beyond these mechanisms direct autoimmune mediated neurotoxicity is postulated. Clinical presentation is highly variable with potentially fluctuating signs and symptoms. Besides multifocal deficits from disseminated CNS involvement, diffuse encephalopathy or psychosis may result from diffuse CNS affection. For systemic vasculitis with CNS involvement, affection of joints, skin and organs may facilitate the diagnostic evaluation. CNS affection in systemic diseases is highly variable and may even precede systemic manifestation. The diagnostic work-up includes clinical evaluation, analysis of autoantibodies, MRI, digital subtraction angiography and biopsy of the affected tissue in doubtful cases. Standard therapy are corticosteroids often combined with immunosuppressants such as azathioprine, methotrexate or mycophenolate mofetil in chronic disease or cyclophosphamid in acute disorder. When therapy can be initiated timely, prognosis of cerebral vasculitis is usually favourable.

Novel lesion detection aids

Several non-invasive and novel aids for the detection of (and in some cases monitoring of) caries lesions have been introduced in the field of 'caries diagnostics' over the last 15 years. This chapter focusses on those available to dentists at the time of writing; continuing research is bound to lead to further developments in the coming years. Laser fluorescence is based on measurements of back-scattered fluorescence of a 655-nm light source. It enhances occlusal and (potentially) approximal lesion detection and enables semi-quantitative caries monitoring. Systematic reviews have identified false-positive results as a limitation. Quantitative light-induced fluorescence is another sensitive method to quantitatively detect and measure mineral loss both in enamel and some dentine lesions; again, the trade-offs with lower specificity when compared with clinical visual detection must be considered. Subtraction radiography is based on the principle of digitally superimposing two radiographs with exactly the same projection geometry. This method is applicable for approximal surfaces and occlusal caries involving dentine but is not yet widely available. Electrical caries measurements gather either site-specific or surface-specific information of teeth and tooth structure. Fixed-frequency devices perform best for occlusal dentine caries but the method has also shown promise for lesions in enamel and other tooth surfaces with multi-frequency approaches. All methods require further research and further validation in well-designed clinical trials. In the future, they could have useful applications in clinical practice as part of a personalized, comprehensive caries management system.

Depiction of small veins draining into the vein of galen using preoperative 3-dimensional navigation in living patients

OBJECTIVE: The purpose of this study was to delineate the anatomy of the precentral cerebellar vein, superior vermian vein, and internal occipital vein using reconstructions of computed tomographic and magnetic resonance imaging scans with navigation software. These data were compared with previous anatomic and angiographic findings to show the resolution and accuracy of the system. METHODS: We retrospectively reviewed 100 patients with intracranial pathologies (50 computed tomographic scans with contrast and 50 magnetic resonance imaging scans with gadolinium) using a neuronavigation workstation for 3-dimensional reconstruction. Particular attention was paid to depiction of the precentral cerebellar vein, superior vermian vein, and internal occipital vein. The data were reviewed and analyzed. RESULTS: The precentral cerebellar vein, superior vermian vein, and its tributary, the supraculminate vein, were depicted in 52 (52%) patients. The internal occipital vein was delineated on 99 (49.5%) sides and joined the basal vein and vein of Galen in 39 (39.4%) and 60 (60.6%) hemispheres, respectively. Comparing these results with previous angiographic studies, the ability of the neuronavigation system for depicting these vessels is similar to that of digital subtraction angiography. CONCLUSION: This study illustrates the possibility of depicting the small vessels draining into the pineal region venous complex using 3-dimensional neuronavigation with an accuracy comparable to that of digital subtraction angiography. This tool provides important information for both surgical planning and intraoperative orientation.

C-Port Flex-A-assisted automated anastomosis for high-flow extracranial-intracranial bypass surgery in patients with symptomatic carotid artery occlusion: a feasibility study. Clinical article

OBJECT: Preliminary experience with the C-Port Flex-A Anastomosis System (Cardica, Inc.) to enable rapid automated anastomosis has been reported in coronary artery bypass surgery. The goal of the current study was to define the feasibility and safety of this method for high-flow extracranial-intracranial (EC-IC) bypass surgery in a clinical series. METHODS: In a prospective study design, patients with symptomatic carotid artery (CA) occlusion were selected for C-Port-assisted high-flow EC-IC bypass surgery if they met the following criteria: 1) transient or moderate permanent symptoms of focal ischemia; 2) CA occlusion; 3) hemodynamic instability; and 4) had provided informed consent. Bypasses were done using a radial artery graft that was proximally anastomosed to the superficial temporal artery trunk, the cervical external, or common CA. All distal cerebral anastomoses were performed on M2 branches using the C-Port Flex-A system. RESULTS: Within 6 months, 10 patients were enrolled in the study. The distal automated anastomosis could be accomplished in all patients; the median temporary occlusion time was 16.6+/-3.4 minutes. Intraoperative digital subtraction angiography (DSA) confirmed good bypass function in 9 patients, and in 1 the anastomosis was classified as fair. There was 1 major perioperative complication that consisted of the creation of a pseudoaneurysm due to a hardware problem. In all but 1 case the bypass was shown to be patent on DSA after 7 days; furthermore, in 1 patient a late occlusion developed due to vasospasm after a sylvian hemorrhage. One-week follow-up DSA revealed transient asymptomatic extracranial spasm of the donor artery and the radial artery graft in 1 case. Two patients developed a limited zone of infarction on CT scanning during the follow-up course. CONCLUSIONS: In patients with symptomatic CA occlusion, C-Port Flex-A-assisted high-flow EC-IC bypass surgery is a technically feasible procedure. The system needs further modification to achieve a faster and safer anastomosis to enable a conclusive comparison with standard and laser-assisted methods for high-flow bypass surgery.

Elevated level of endothelin-1 in cerebrospinal fluid and lack of nitric oxide in basilar arterial plasma associated with cerebral vasospasm after subarachnoid haemorrhage in rabbits

BACKGROUND: The role of endothelin-1 (ET-1) and nitric oxide (NO) as two important mediators in the development of cerebral vasospasm (CVS) after subarachnoid haemorrhage (SAH) is controversial. The objective of this study was to determine whether local levels of ET-1 and NO in cerebral arterial plasma and/or in cerebrospinal fluid (CSF) are associated with the occurrence of CVS after SAH. METHODS: CVS was induced using the one-haemorrhage rabbit model and confirmed by digital subtraction angiography of the rabbits' basilar artery on day 5. Prior to sacrifice, local CSF and basilar arterial plasma samples were obtained by a transclival approach to the basilar artery. Systemic arterial plasma samples were obtained. ET-1 levels were determined by immunometric technique (pg/ml +/- SEM) and total nitrate/nitrite level spectrophotometrically (micromol/l +/- SEM). FINDINGS: Angiographic CVS was documented after SAH induction (n = 12, P < 0.05). The ET-1 level in CSF was significantly elevated by 27.3% to 0.84 +/- 0.08 pg/ml in SAH animals (n = 7) in comparison to controls (0.66 +/- 0.04 pg/ml, n = 7, P < 0.05). There was no significant difference in ET-1 levels in systemic and basilar arterial plasma samples of SAH animals compared to controls. A significant lack of local NO metabolites was documented in basilar arterial plasma after SAH (36.8 +/- 3.1 micromol/l, n = 6) compared to controls (61.8 +/- 6.2 micromol/l, n = 6, P < 0.01). CONCLUSION: This study demonstrates that an elevated ET-1 level in CSF and local lack of NO in the basilar arterial plasma samples are associated with CVS after experimental SAH.

High-resolution three-dimensional 3 T magnetic resonance angiography for the evaluation of experimental aneurysm in the rabbit

OBJECTIVE: The standard technique of two-dimensional intra-arterial digital subtraction angiography (2D-DSA) for the imaging of experimental rabbit aneurysms is invasive and has considerable surgical risks. Therefore, minimally invasive techniques ideally providing three-dimensional imaging for intervention planning and follow-up are needed. This study evaluates the feasibility and quality of three-dimensional 3-T magnetic resonance angiography (3D-3T-MRA) and compares 3D-3T-MRA with 2D-DSA in experimental aneurysms in the rabbit. METHOD: Three microsurgically created aneurysms in three rabbits were evaluated using 2D-DSA and 3D-3T-MRA. Imaging of the aneurysms was performed 2 weeks after creation using 2D-DSA and contrast-enhanced (CE) MRA. Measurements included aneurysm dome (length and width) and aneurysm neck. Aneurysm volumes were determined using CE-MRA. RESULTS: The measurements of the aneurysms' dimensions and the evaluation of vicinity vessels with both techniques showed a good correlation. The mean aneurysm length, aneurysm width and neck width measured with DSA (6.9, 4.1 and 2.8 mm, respectively) correlated with the measurements performed in 3D-3T-MRA (6.9, 4 and 2.5 mm, respectively). The mean aneurysm volumes measured with CE-MRA was 46.7 mm(3). CONCLUSION: 3D-3T CE-MRA is feasible and less invasive and is a safer imaging alternative to DSA for experimental aneurysm. Additionally, aneurysm technique this precise offers the possibility of repetitive 3D aneurysm volumetry for long-term follow-up studies after endovascular aneurysm occlusion.