Kimmo Lappalainen

Head and Neck Arteriovenous Malformations: Results of Ethanol Sclerotherapy

BACKGROUND AND PURPOSE: Peripheral AVM is a locally aggressive disease with a high tendency to recur; its treatment is complex, especially in the anatomically delicate head and neck area. Here, we report results of ethanol sclerotherapy for head and neck AVM and discuss its potential use for peripheral AVM. MATERIALS AND METHODS: We retrospectively assessed degree of AVM eradication, complications, and clinical or imaging signs of recurrence for 19 patients treated with ethanol sclerotherapy for head and neck AVM (1 intraosseous, 18 soft-tissue AVMs). RESULTS: Of the 19 patients, 11 had complete eradication of arteriovenous shunting at DSA, with 1 recurrence (mean follow-up 15 months), and for 7 patients, treatment is ongoing. During 59 treatment sessions, 12 patients experienced 14 complications, 1 leading to permanent functional damage. CONCLUSIONS: Ethanol sclerotherapy has potential for complete eradication of head and neck AVM with low recurrence within the first year after completion of treatment. Complete eradication may require several treatment sessions during which complications should be minimized with careful techniques.

An interdisciplinary specialist team leads to improved diagnostics and treatment for paediatric patients with vascular anomalies.

Patients with vascular anomalies are often misdiagnosed, leading to delayed or improper treatment. The aim of this study was to evaluate the impact of an interdisciplinary team on the diagnosis and treatment of paediatric patients with vascular anomalies.

IV Thrombolysis-Bridging and Endovascular Treatment for Occlusive Internal Carotid Artery Dissection with Tandem Occlusion

Compared to other etiologies of ischemic stroke, occlusive internal carotid artery dissection responds worse to intravenous (IV) thrombolysis. Intracranial tandem occlusion is a predictor of poor outcome. A direct endovascular approach has been proposed as a safe and probably superior alternative to IV thrombolysis. However, it may lead to considerable treatment delays. We used rapidly initiated IV thrombolysis-bridging and subsequent endovascular treatment in two patients with severe hemispheric ischemia due to occlusive internal carotid artery dissection with tandem occlusion and achieved good outcomes. Minimizing recanalization times likely improves patient outcome and IV thrombolysis-bridging may be a reasonable strategy to achieve this. The positive initial results obtained with endovascular approaches and IV thrombolysis-bridging in this patient group deserve further scientific exploration.

Sclerotherapy complications of peripheral venous malformations

Background Sclerotherapy is often the primary treatment for peripheral venous malformations. It is mostly sufficient alone, but can be combined with other endovascular techniques. Despite its mini-invasiveness, it is not without potentially severe complications. Here, we systematically report sclerotherapy complications in trunk and extremity venous malformations. Methods We retrospectively assessed the complications of 127 consecutive patients who had received sclerotherapy for peripheral venous malformation in our tertiary care unit (January 2007–August 2013). We applied the Clavien–Dindo classification to grade the severity of complications. We mostly used detergent sclerosants (85.7%), and less often ethanol (5.7%) or bleomycin (4.2%). In 4.2% of the procedures, we combined glue, coils, endovascular laser or particles to sclerotherapy. Results The overall complication rate per procedure was 12.5%. Most complications (83.3%) were local and managed conservatively. We encountered four severe complications, all related to blood coagulopathy. Subcutaneous lesion location and use of ethanol significantly increased the risk of local complications. Conclusion Sclerotherapy alone or combined with other endovascular techniques is a safe method for local venous malformations with moderate risk for conservatively manageable complications. Blood coagulopathy constitutes a risk for, otherwise rare, severe complications.

Intravenous alteplase versus rescue endovascular procedure in patients with proximal middle cerebral artery occlusion

Objectives To compare outcome of ischaemic stroke patients undergoing rescue endovascular procedure for proximal middle cerebral artery occlusion with matched patients without endovascular procedure after unsuccessful intravenous thrombolysis. Methods Endovascularly treated patients with middle cerebral artery occlusion (n = 41) were matched by propensity score with similar patients treated by intravenous thrombolysis and having a considerable post-thrombolysis neurological deficit (n = 82). We compared their three-month outcome (modified Rankin Scale) and frequency of symptomatic intracerebral haemorrhage. For the endovascular group, we report onset-to-puncture time, onset-to-recanalization time, and recanalization rates. Results In age, gender, time from onset, admission National Institutes of Health Stroke Scale, systolic and diastolic blood pressure, blood glucose, history of hypertension, diabetes mellitus, hyperlipidaemia, atrial fibrillation, and congestive heart failure, and in aetiology, the groups were similar. Endovascular group patients had a recanalization rate of 90%, and more often reached three-month modified Rankin Scale 0–2 (36·6% vs. 18·3%, P = 0·03). Mortality was equally common (19·5%) in both groups, and frequency of symptomatic intracerebral haemorrhage was 9·8% vs. 14·6% (P = 0·45). The endovascular groups median onset-to-puncture time was four-hours and six-minutes and onset-to-recanalization time was five-hours and 12 min. The latter time was more than one-hour longer in patients treated under general anaesthesia compared with patients treated under conscious sedation (median four-hours 50 min vs. five-hours 58 min; P < 0·01). Conclusions Rescue endovascular approach increases likelihood of recanalization and may improve functional outcome in acute ischaemic stroke patients with proximal middle cerebral artery occlusion who did not respond to intravenous thrombolysis.

The evolution of the Helsinki frostbite management protocol

BACKGROUND Severe frostbite can result in devastating injuries leading to significant morbidity and loss of function from distal extremity amputation. The modern day management approach to frostbite injuries is evolving from a historically very conservative approach to the increasingly reported use of early interventional angiography and fibrinolysis with tPA. The aim of this study was to evaluate the results of our frostbite treatment protocol introduced 3 years ago. METHODS All frostbite patients underwent first clinical and then Doppler ultrasound examination. Angiography was conducted if certain clinical criteria indicated a severe frostbite injury and if there were no contraindications to fibrinolysis. Intra-arterial tissue plasminogen activator (tPA) was then administered at 0.5-1mg/h proximal to the antecubital fossa (brachial artery) or popliteal fossa (femoral artery) if angiography confirmed thrombosis, as well as unfractionated intravenous heparin at 500 units/h. The vasodilator iloprost was administered intravenously (0.5-2.0ng/kg/min) in selected cases. RESULTS 20 patients with frostbite were diagnosed between 2013-2016. Fourteen patients had a severe injury and angiography was performed in 10 cases. The total number of digits at risk was 111. Nine patients underwent fibrinolytic treatment with tPA (including one patient who received iloprost after initial non response to tPA), 3 patients were treated with iloprost alone and 2 patients received neither treatment modality (due to contraindications). The overall digital salvage rate was 74.8% and the Hennepin tissue salvage rate was 81.1%. One patient developed a catheter-site pseudoaneurysm that resolved after conservative treatment. CONCLUSIONS Prompt referral to a facility where interventional radiology and 24/7 laboratory services are available, and the combined use of tPA and iloprost, may improve outcome after severe frostbite.

Angiomatosis of soft tissue as an important differential diagnosis for intramuscular venous malformations

Background We aimed to improve management of extremity low-flow vascular malformations by analyzing the histology and imaging of venous malformations (VMs) not responsive to sclerotherapy. Method We reviewed patient records of 102 consecutive patients treated with sclerotherapy for extremity VM in our institution to identify patients who had undergone surgery due to insufficient response. We semi-quantitatively analysed the tissue specimens and compared histological findings to those in preoperative imaging. Result The number of patients operated on was 19 (18.6%); 15 of them had lower-extremity intramuscular lesions. The histological pattern of 13 of these 15 lesions corresponded to angiomatosis of soft tissue (AST). All other lesions treated surgically were VMs. The histology of AST was distinctive but magnetic resonance imaging findings often overlapped with those of VM. Conclusion AST is easily mixed with intramuscular VM. The differentiation of these two entities has therapeutic importance. We emphasize the role of histology in the differential diagnostics of intramuscular slow-flow vascular malformations.

Actual and Potential Radiation Exposures in Digital Radiology: Analysis of Cumulative Data, Implications to Worker Classification and Occupational Exposure Monitoring

Radiation worker categorization and exposure monitoring are principal functions of occupational radiation safety. The aim of this study was to use the actual occupational exposure data in a large university hospital to estimate the frequency and magnitude of potential exposures in radiology. The additional aim was to propose a revised categorization and exposure monitoring practice based on the potential exposures. The cumulative probability distribution was calculated from the normalized integral of the probability density function fitted to the exposure data. Conformity of the probabilistic model was checked against 16 years of national monitoring data. The estimated probabilities to exceed annual effective dose limits of 1 mSv, 6 mSv and 20 mSv were 1:1000, 1:20 000 and 1:200 000, respectively. Thus, it is very unlikely that the class A categorization limit of 6 mSv could be exceeded, even in interventional procedures, with modern equipment and appropriate working methods. Therefore, all workers in diagnostic and interventional radiology could be systematically categorized into class B. Furthermore, current personal monitoring practice could be replaced by use of active personal dosemeters that offer more effective and flexible means to optimize working methods.