Soenke Langner

Inhibition of Restenosis in Femoropopliteal Arteries Paclitaxel-Coated Versus Uncoated Balloon: Femoral Paclitaxel Randomized Pilot Trial

Background— The success of percutaneous intervention in peripheral arterial disease is limited by restenosis. The aim of the present pilot study was to evaluate a novel method of local drug delivery. Methods and Results— This randomized multicenter study with blinded reading enrolled 87 patients in Rutherford class 1 to 4 with occlusion or hemodynamically relevant stenosis, restenosis, or in-stent restenosis of femoropopliteal arteries. Treatment was performed by either conventional uncoated or paclitaxel-coated balloon catheters. The primary end point was late lumen loss at 6 months. Secondary end points included restenosis rate, ankle brachial index, Rutherford class, target lesion revascularization, and tolerance up to >18 months. Before intervention, there were no significant differences in lesion characteristics such as reference diameter (5.3±1.1 versus 5.2±1.0 mm), degree of stenosis (84±11% versus 84±16%), proportion of restenotic lesions (36% versus 33%), and mean lesion length (5.7 cm [0.8 to 22.6 cm] versus 6.1 cm [0.9 to 19.3 cm]) between treatment groups. The 6-month follow-up angiography performed in 31 of 45 and 34 of 42 patients showed less late lumen loss in the coated balloon group (0.5±1.1 versus 1.0±1.1 mm; P=0.031). The number of target lesion revascularizations was lower in the paclitaxel-coated balloon group than in control subjects (3 of 45 versus 14 of 42 patients; P=0.002). Improvement in Rutherford class was greater in the coated balloon group (P=0.045), whereas the improvement in ankle brachial index was not different. The difference in target lesion revascularizations between treatment groups was maintained up to >18 months. No adverse events were assessed as related to balloon coating. Conclusions— In this pilot trial, paclitaxel balloon coating caused no obvious adverse events and reduced restenosis in patients undergoing angioplasty of femoropopliteal arteries.

Functional Status of Peripheral Blood T-Cells in Ischemic Stroke Patients

Stroke is a major cause of disability and leading cause of death in the northern hemisphere. Only recently it became evident that cerebral ischemia not only leads to brain tissue damage and subsequent local inflammation but also to a dramatic loss of peripheral blood T-cells with subsequent infections. However, only scarce information is available on the activation status of surviving T cells. This study therefore addressed the functional consequences of immunological changes induced by stroke in humans. For this purpose peripheral blood T-cells were isolated from 93 stroke patients and the expression of activation makers was determined. In addition ex vivo stimulation assays were applied to asses the functionality of T cells derived from blood of stroke patients. Compared to healthy controls, stroke patients demonstrated an enhanced surface expression of HLA-DR (p<0.0001) and CD25 (p = 0.02) on T cells, revealing that stroke leads to T cell activation, while CTLA-4 remained undetectable. In vitro studies revealed that catecholamines inhibit CTLA-4 upregulation in activated T cells. Ex vivo, T cells of stroke patients proliferated unimpaired and released increased amounts of the proinflammatory cytokine TNF-α (p<0.01) and IL-6 (p<0.05). Also, in sera of stroke patients HMGB1 concentrations were increased (p = 0.0002). The data demonstrate that surviving T cells in stroke patients remain fully functional and are primed towards a TH1 response, in addition we provide evidence that catecholamine mediated inhibition of CTLA-4 expression and serum HMGB1 release are possible mediators in stroke induced activation of T cells.

Laser Ablation of Liver Metastases from Colorectal Cancer with MR Thermometry: 5-Year Survival

PURPOSE To determine technical success, technique effectiveness, complications, and survival after laser ablation of liver metastases from colorectal cancer. MATERIALS AND METHODS Eighty-seven consecutive patients (65 men and 22 women; mean age, 62.8 years) with 180 liver metastases from colorectal carcinoma were included between 1998 and 2005. They underwent laser ablation with magnetic resonance (MR) thermometry in 170 sessions. Indications for laser ablation were locally unresectable tumors (16.1%), metastases in both liver lobes (34.5%), and refusal of surgery and/or general contraindications to surgery (49.4%). Technical success, technique effectiveness, and complication and survival rates were evaluated retrospectively. RESULTS Technical success was achieved in 178 of 180 sessions (99%). Follow-up after 24-48 hours demonstrated an effectiveness rate of 85.6%. Local tumor progression rate was 10% after 6 months. Major complications included large pleural effusion, large subcapsular hematoma, abscess, large pneumothorax, pleuritis with fever, intrahepatic hemorrhage, and biloma. Mean survival from the time of diagnosis of the primary tumor was 50.6 months for all patients treated (95% CI, 44.9-56.3 months). Median survival time was 54 months and survival rates were 95.7% at 1 year, 86.2% at 2 years, 72.4% at 3 years, 50.1% at 4 years, and 33.4% at 5 years. The mean survival time after the first treatment was 31.1 months (95% CI, 26.9-35.3 months). CONCLUSIONS Laser ablation of liver metastases of colorectal cancer with MR thermometry appears safe and efficacious. Although the results are encouraging, direct comparison with other ablative modalities in a prospective clinical trial would be necessary to definitely show one modality is superior.

Incidence of blunt craniocervical artery injuries: use of whole-body computed tomography trauma imaging with adapted computed tomography angiography.

BACKGROUND:The incidence of traumatic craniocervical artery dissection varies in published trauma series. OBJECTIVE:To determine the frequency of traumatic craniocervical artery injury in polytrauma patients by using standardized whole-body trauma computed tomography with adapted computed tomography angiography of the craniocervical vessels. METHODS:A total of 718 consecutive patients requiring whole-body trauma computed tomography (16-row multislice) because of the mechanism of their injury patterns and an Injury Severity Scale score greater than 16 were analyzed prospectively. After a cranial scan, computed tomography angiography of the craniocervical vessels with 40 mL of iodinated contrast agent was performed using bolus tracking. RESULTS:The overall incidence of blunt carotid and vertebral injuries (BCVIs) in the screened population was 1.7%. BCVIs were observed in 27.3% of patients with detected isolated cervical spine injuries and in 3.9% of patients with isolated cranial fractures with or without intracranial hemorrhage, whereas 5.3% of patients with combined cervical and cranial lesions were associated with BCVIs. In addition, 0.4% of BCVIs occurred in patients without evidence of head or neck trauma. CONCLUSION:Whole-body trauma computed tomography with an adapted scanning protocol for the craniocervical vessels is a fast, safe, and feasible method for detecting vascular injuries. It allows prompt further treatment if necessary. Computed tomography angiography could be a part of a broad screening protocol for craniocervical vessels in documented injuries of the head and neck and in trauma mechanisms influencing the craniocervical region as well.

MR Microscopy of the human eye at 7.1 T and correlation with histopathology-proof of principle.

Objective: Magnetic resonance imaging (MRI) at 1.5 and 3.0 Tesla with small surface coils is a well-established procedure in the diagnosis of masses of the eye and orbital cavity. Until now histological examination has been required to obtain definitive information on tumor extent or possible infiltration of surrounding structures. With ultra-high-field MRI, however, it is possible to evaluate tumor morphology as well as possible extension into surrounding structures with submillimeter spatial resolution. Materials and Methods: We present a female patient with a uveal melanoma who underwent a preoperative MRI at 1.5 T (spatial resolution = 0.9 x 0.9 x 4 mm/voxel). Postoperatively, the enucleated specimen was examined in a 7.1 Tesla high-field MRI scanner (slice thickness = 500 µm, matrix size = 512 x 512 pixels, spatial resolution = 78 x 78 x 500 µm/voxel, acquisition time = 8:20 min per plane). Finally, the specimen was examined histologically, and the histological and MRI results were correlated. Results: Ultra-high-field MRI at 7.1 Tesla visualized the uveal melanoma and anatomical structures of the bulb with high resolution, enabling definitive assessment of tumor morphology and extent. Subsequent histological examination confirmed the MRI findings regarding origin, internal structure, and extent of the tumor. Conclusion: MR microscopy correlates strongly with histology, suggesting that this new imaging modality has the potential for noninvasively assessing tumor morphology, extent, and infiltration of surrounding structures. The examination was performed ex vivo and demonstrates that diagnostic assessment of malignant masses is feasible using high-resolution MR microscopy.

Intravenous Thrombolysis and Passes of Thrombectomy as Predictors for Endovascular Revascularization in Ischemic Stroke

BACKGROUND Patient selection for endovascular revascularization treatment (ERT) in acute ischemic stroke depends on the expected benefit-risk ratio. As rapid revascularization is a major determinant of good functional outcome, we aimed to identify its predictors after ERT. METHODS Consecutive stroke patients from a single stroke center with distal internal carotid artery-, proximal middle cerebral artery- or T-occlusions treated with ERT were retrospectively selected. We assessed admission noncontrast computed tomography and computed tomography angiography for thrombus location, thrombus load (clot burden score), and collateral status. Clinical data were extracted from medical charts. Univariate and multivariate regression analyses were performed to identify predictors of revascularization (thrombolysis in cerebral infarction ≥2b) after ERT. RESULTS A total of 63 patients were identified (median age, 73 years; interquartile range: 62-77; 40 females). Sixteen patients (25.4%) underwent intravenous thrombolysis (ivT) before ERT. Twenty-two patients (34.9%) had additional intra-arterial application of recombinant tissue plasminogen activator. The overall recanalization rate was 66.7%, and 9.5% had symptomatic intracranial bleeding. In-hospital mortality was 15%, and 30% reached good functional outcome at discharge. In the univariate analysis, preceding ivT and the number of passes for thrombectomy (dichotomized ≤2 versus >2) were associated with recanalization. There was a trend for number of thrombectomy passes (as continuous variable) and multimodal ERT. In the multivariate regression analysis, ivT prior to ERT and passes of thrombectomy were identified as independent predictors for recanalization. CONCLUSION ivT and lower passes of thrombectomy are associated with recanalization after ERT for ischemic stroke with proximal vessel occlusions.

Diffusion tensor imaging abnormalities in photosensitive juvenile myoclonic epilepsy

Multiple structural white matter abnormalities have been described in patients with juvenile myoclonic epilepsy (JME). In the present study, the question of whether microstructural variations exist between the two subgroups of JME, with and without photoparoxysmal responses (PPR positive and negative), was addressed using diffusion tensor imaging.

In vivo 7.1 T magnetic resonance imaging to assess the lens geometry in rabbit eyes 3 years after lens-refilling surgery

PURPOSE: To evaluate the utility of high‐resolution magnetic resonance imaging (MRI) in assessing the normal and refilled lens geometry in rabbits after lens‐refilling surgery. SETTING: University of Rostock, Rostock, Germany. DESIGN: Experimental study. METHODS: High‐resolution ocular MRIs were acquired (7.1 T ClinScan) using a 2‐channel coil with 4 coil elements and T2‐weighted turbo spin‐echo sequences (slice thickness 700 μm, field of view 40 mm × 40 mm) in rabbits after lens refilling surgery combined with intraoperative treatment to prevent lens epithelial cell proliferation. Single slices were used to assess the refilled lenses 3 years postoperatively. RESULTS: The entire geometry (cross‐sectional area, radius of curvature, axial and equatorial diameters) of the crystalline and refilled lenses was visualized by in vivo 7.1T MRI 3 years postoperatively (in‐plane resolution: 125 μm × 125 μm). In refilled eyes, the capsule and the homogenous silicone polymer remained in close contact with no visible interface. The dimensions of the refilled lens were significantly smaller than those of the crystalline lens of the contralateral eye. CONCLUSIONS: High‐resolution MRI allows in vivo visualization and analysis of the spatial arrangement of the lens in rabbit eyes after lens refilling surgery and overcomes a number of major limitations in the quantitative evaluation of the lens shape. Further efforts are required to optimize the amount of polymer injected during lens refilling to achieve a predictable refractive outcome after lens refilling surgery. Financial Disclosure: Drs. Stachs, Langner, Sternberg, Martin, Schmitz, Hosten and Guthoff have no financial or proprietary interest in any material or method mentioned. Additional financial disclosure is found in the footnotes.

Perfusion CT scanning and CT angiography in the evaluation of extracranial-intracranial bypass grafts.

OBJECT Extracranial-intracranial (EC-IC) bypass surgery remains an important treatment alternative for patients with occlusive cerebrovascular disease. The aim of the present study was to use perfusion CT and CT angiography (CTA) to evaluate cerebral hemodynamics and bypass patency in patients with occlusive cerebrovascular disease before and after EC-IC bypass surgery. METHODS Ten patients underwent perfusion CT and CTA before and after bypass surgery. Preoperative and postoperative digital subtraction angiography served as the diagnostic gold standard. An artery bypass was established from the superficial temporal artery to a cortical branch of the middle cerebral artery. Perfusion CT scanning was performed at the level of the basal ganglia. Color-coded perfusion maps of cerebral blood volume, cerebral blood flow, and time to peak were calculated. RESULTS Preoperative perfusion CT showed significant prolonged time to peak and reduced cerebral blood flow of the affected hemisphere. Postoperative neurological deterioration did not develop in any patient. Computed tomography angiography provided adequate evaluation of the anastomoses as well as the course and caliber of the bypass and confirmed bypass patency in all patients. Postoperative perfusion CT showed improved cerebral hemodynamics with a return to nearly normal perfusion parameters. CONCLUSIONS Computed tomography angiography is a noninvasive and reliable tool for evaluating patients with EC-IC bypass. Perfusion CT allows monitoring of hemodynamic changes after bypass surgery. The combination of both modalities enables noninvasive anatomical and functional analysis of superficial temporal artery-middle cerebral artery anastomoses using a single CT protocol. Hemodynamic evaluation of patients with occlusive cerebrovascular disease before and after surgery may improve the prediction of outcome and may help identify patients in whom a bypass procedure can be performed.

Intraarterial Recombinant Tissue Plasminogen Activator Thrombolysis of Acute and Semiacute Lower Limb Arterial Occlusion: Quality Assurance, Complication Management, and 12-Month Follow-Up Reinterventions

OBJECTIVE The purpose of this study is to assess the efficacy of intraarterial thrombolysis in acute and semiacute occlusions of the lower limb. MATERIALS AND METHODS A total of 77 native arteries and 52 bypass grafts were investigated in 129 patients (mean [± SD] age, 64.6 ± 11.1 years) with acute (i.e., symptoms for ≤ 14 days) or semiacute (i.e., symptoms for > 14 days) peripheral arterial occlusions of the lower limb treated by catheter-directed recombinant tissue plasminogen activator (rt-PA) thrombolysis. Therapeutic success was retrospectively analyzed according to vessel type and duration of occlusion. Morbidity and mortality rates associated with thrombolytic treatment were calculated. The hospitalization period after primary intervention was recorded. Reinterventions and amputations were assessed at 12-month follow-up. RESULTS Recanalization was accomplished by rt-PA thrombolysis in 73.6% of all cases. There was no difference in primary therapeutic success between native arteries and bypass grafts (p = 0.601). Thrombolysis was more effective in acute peripheral occlusions, and hospital stays were shorter than those for patients with semiacute occlusion (p = 0.001). The morbidity rate was 31% (minor complications, 20.2%; major complications, 10.9%), and the mortality rate was 2.3%. Within 12 months, radiologic and surgical interventions were necessary for 27 patients. The limb salvage rate after primarily successful recanalization was 89.5%. CONCLUSION Intraarterial rt-PA thrombolysis is an effective and reasonable method for treating acute peripheral arterial occlusion. The method is less effective in semiacute occlusions, leading to extended hospitalization. Within 12 months, a quarter of the patients required reinterventions, and amputations were necessary in 10% of the cases.