[Treatment of tandem occlusions of the common and internal carotid arteries]. / Behandlung von Tandemstenosen der A. carotis communis und A. carotis interna.

BACKGROUND: Proximal carotid tandem lesions are defined as multilevel lesions with significant (> 50%) atherosclerotic disease involving the internal carotid artery (ICA) in combination with the proximal ipsilateral common carotid artery (CCA) or innominate artery (IA). It is a relatively rare disease with an incidence of less than 5% in all patients with carotid stenosis at the level of the bifurcation. METHODS: These patients are at high surgical risk and were, therefore, excluded from current randomized controlled trials. Although the effectiveness of carotid endarterectomy (CEA) and carotid stenting (CAS) in stroke prevention for patients is established, the optimal treatment approach for the subgroup of patients with a proximal tandem lesion is still controversial. Treatment of this condition is not well understood because it is difficult to determine the risk of each individual lesion becoming symptomatic. Therefore, concurrent treatment of severe (> 70% stenosis) proximal lesions is recommended when treating severe stenosis at the carotid bifurcation. CONCLUSION: This disease can lead to embolic ischemic strokes or hemodynamic compromise. It is not possible to determine diagnostically which lesion led to the clinical symptoms, which is why both lesions should be corrected.

Recurrent reversible in-stent-stenosis after flow diverter treatment.

Flow diverter stents (FDS) are well established in the treatment of intracranial aneurysms which are difficult to treat with conventional endovascular techniques. However, they carry a relatively high risk of specific complications compared to conventional stents. A minor but frequent finding is the occurrence of reversible in-stent-stenosis (ISS) that tend to resolve spontaneously over time. Here, we report the case of a patient in their 30s who was treated with FDS for bilateral paraophthalmic internal carotid artery (ICA) aneurysms. ISS were found at the respective early follow-up examinations on both sides and had resolved at the 1-year follow-up examinations. Surprisingly ISS reoccurred at both sides in later follow-up examinations and again resolved spontaneously. The recurrence of ISS after resolution is a finding that has not been described previously. Its incidence and further development should be investigated systematically. This might contribute to our understanding of the mechanisms underlying the effect of FDS.

Endovascular Treatment Strategies for Aneurysms of the Origin of the Posterior Inferior Cerebellar Artery.

BACKGROUND: Treatment of aneurysms at the origin of the posterior inferior cerebellar artery (PICA) is challenging. Surgery is difficult due to the deep location and proximity to cranial nerves and endovascular treatment is complicated due to the often tortuous anatomy of the PICA and its small diameter. The purpose of this study is to report our experience with the endovascular treatment of aneurysms at the origin of the PICA. METHODS: Consecutive patients with aneurysms at the origin of the PICA who were endovascularly treated at our department were identified from our registry of neuro-angiographies. Clinical, angiographic, and treatment data were analyzed. Endpoints included successful occlusion and recurrence. RESULTS: Twenty-nine patients were included. 79.3% of the aneurysms were wide-neck with a dome-to-neck ratio <2.65.5% of all endovascular procedures were performed by coiling alone. The procedural rupture rate was 18.75% for endovascularly treated aneurysms presenting with subarachnoid hemorrhage (SAH). Successful embolization was achieved non-significantly more often in the coiling-only group (94.7% vs. 70%, P = 0.066). Aneurysm recurrence after successful occlusion was observed in one case. CONCLUSIONS: Though aneurysm and parent vessel characteristics were challenging successful occlusion was achieved in a high rate of treatments, often with standalone coiling. Adjunctive techniques like retrograde stenting seem promising to further enhance endovascular results. Interestingly aneurysms arising solely from the origin of the PICA without the V4-segment involved presented with SAH significantly more often and wide-neck aneurysms presenting with SAH had a significantly higher periinterventional rupture rate.

[Interdisciplinary neurovascular conference-opportunities and benefits]. / Interdisziplinäre Neurovaskuläre Konferenz ­ Chancen und Nutzen.

CLINICAL/METHODOLOGICAL ISSUE: The neurovascular conference is a discussion platform for the fields of neurology, neurosurgery, vascular surgery and neuroradiology. METHODOLOGICAL INNOVATIONS: Interdisciplinary exchange allows creation of individual treatment concepts for elective patients with neurovascular diseases regarding further measures for prevention, treatment and aftercare. ACHIEVEMENTS: Establishment of individual treatment concepts for patients with neurovascular diseases regarding treatment recommendations based on current guidelines, scientific evidence and treatment standards based on them. PERFORMANCE: Elective patients with neurovascular diseases.

[Spinal neoplasms]. / Spinale Neoplasien.

Spinal neoplasms are generally rare disorders but play an important role in the differential diagnosis of space-occupying masses of the spinal axis. Although there are several different classification criteria (histological origin, dignity, positional relationship to the spine), the standard classification of spinal neoplasms based on the relationship to the dura mater into extraspinal, intraspinal extramedullary and intraspinal intramedullary is used. Magnetic resonance imaging is the gold standard for the morphological imaging of spinal neoplasms, followed by computed tomography. In addition to localization and symptoms, the patient's age is essential with respect to the diagnosis of the possible tumor entity.

Utility of Hounsfield unit in the diagnosis of tandem occlusion in acute ischemic stroke.

BACKGROUND: Tandem occlusions can complicate medical and endovascular stroke treatment. To identify these occlusions, computed tomography angiography (CTA) represents the best imaging modality. However, CTA is still not initially performed in some patients not admitted directly to stroke centers. Early identification of an additional occlusion of the proximal extracranial internal carotid artery may improve the best suitable treatment strategy. The purpose of this study was to find a valuable threshold of thrombus attenuation in a non-contrast head CT (NCCT) scan to facilitate a safe diagnosis of tandem occlusions. MATERIALS AND METHODS: Consecutive patients with acute middle cerebral artery (MCA) occlusions who underwent endovascular treatment were identified from our registry of neuroendovascular interventions. Thrombus attenuations of the affected MCA and contralateral vessel were measured by NCCT. To compare individual baseline blood attenuations, the difference between the thrombus attenuation and the contralateral MCA attenuation (referred to as ΔTM) was calculated. RESULTS: Three hundred and twenty-five patients were included. There was a highly significant difference between mean thrombus attenuation with isolated MCA occlusion and additional extracranial internal carotid artery (ICA) occlusion (49.9 ± 8 vs. 56.2 ± 10 Hounsfield units (HU); P < 0.001). The area under the receiver operating characteristic curve of ΔTM was 0.72. The optimal threshold value was 13.5 HU, with a sensitivity of 67.5% and a specificity of 68.6%. CONCLUSION: Despite a significant difference in thrombus attenuation in MCA occlusions with an additional extracranial ICA occlusion compared with isolated MCA occlusions, a relevant threshold of thrombus attenuation was not found.

Transient in-stent stenosis: a common finding after flow diverter implantation.

BACKGROUND AND PURPOSE: In recent years, implantation of flow diverters has emerged as an option for the endovascular treatment of intracranial aneurysms. One complication of treatment with flow diverters is the occurrence of in-stent stenosis, which has been reported to be partially reversible. The purpose of our study was to assess the incidence and dynamics of in-stent stenosis on angiographic short term and long term follow-up after treatment with flow diverters. METHODS: A retrospective review of our prospectively maintained database identified all patients with intracranial internal carotid artery (ICA) aneurysms treated by flow diverters at our institution between 2014 and 2017. Clinical charts, procedural data, and angiographic results were reviewed. RESULTS: 18 patients were included. The mean short term follow-up was 92±19 days and mean long term follow-up was 449±120 days after treatment. No neurologic complications were observed. There was no procedure related mortality. Long term angiographic results showed complete occlusion in 83.3%, neck remnants in 11.1%, and incomplete occlusion in 5.5% of cases. In-stent stenosis was observed in all cases. Mean stenosis improved significantly from 30% on short term follow-up to 12% on long-term follow-up (P<0.0001). CONCLUSION: In-stent stenosis is a common finding on short term follow-up after the treatment with flow diverters but improves over time.