30 research outputs found
Diffusion-weighted MRI reflects proliferative activity in primary CNS lymphoma
Purpose: To investigate if apparent diffusion coefficient (ADC) values within primary central nervous system lymphoma correlate with cellularity and proliferative activity in corresponding histological samples.
Materials and Methods: Echo-planar diffusion-weighted magnetic resonance images obtained from 21 patients with primary central nervous system lymphoma were reviewed retrospectively. Regions of interest were drawn on ADC maps corresponding to the contrast enhancing parts of the tumors. Biopsies from all 21 patients were histologically analyzed. Nuclei count, total nuclei area and average nuclei area were measured. The proliferation index was estimated as Ki-67 positive nuclei divided by total number of nuclei. Correlations of ADC values and histopathologic parameters were determined statistically. Results: Ki-67 staining revealed a statistically significant correlation with ADCmin (r = -0.454, p = 0.038), ADCmean (r = -0.546, p = 0.010) and ADCmax (r = -0.515, p = 0.017). Furthermore, ADCmean correlated in a statistically significant manner with total nucleic area (r = -0.500, p = 0.021). Conclusion: Low ADCmin, ADCmean and ADCmax values reflect a high proliferative activity of primary cental nervous system lymphoma. Low ADCmean values—in concordance with several
previously published studies—indicate an increased cellularity within the tumor
First Experience of Three Neurovascular Centers With the p64MW-HPC, a Low-Profile Flow Diverter Designed for Proximal Cerebral Vessels With Antithrombotic Coating
Background: In the last decade, flow diversion (FD) has been established as
hemodynamic treatment for cerebral aneurysms arising from proximal and distal cerebral
arteries. However, two significant limitations remain—the need for 0.027” microcatheters
required for delivery of most flow diverting stents (FDS), and long-term dual anti-platelet
therapy (DAPT) in order to prevent FDS-associated thromboembolism, at the cost
of increasing the risk for hemorrhage. This study reports the experience of three
neurovascular centers with the p64MW-HPC, a FDS with anti-thrombotic coating that
is implantable via a 0.021” microcatheter.
Materials and methods: Three neurovascular centers contributed to this retrospective
analysis of patients that had been treated with the p64MW-HPC between March 2020
and March 2021. Clinical data, aneurysm characteristics, and follow-up results, including
procedural and post-procedural complications, were recorded. The hemodynamic effect
was assessed using the O’Kelly–Marotta Scale (OKM).
Results: Thirty-two patients (22 female, mean age 57.1 years) with 33 aneurysms
(27 anterior circulation and six posterior circulation) were successfully treated with
the p64MW-HPC. In 30/32 patients (93.75%), aneurysmal perfusion was significantly
reduced immediately post implantation. Follow-up imaging was available for 23
aneurysms. Delayed aneurysm perfusion (OKM A3: 8.7%), reduction in aneurysm size
(OKM B1-3: 26.1%), or sufficient separation from the parent vessel (OKM C1-3 and
D1: 65.2%) was demonstrated at the last available follow-up after a mean of 5.9
months. In two cases, device thrombosis after early discontinuation of DAPT occurred.
One delayed rupture caused a caroticocavernous fistula. The complications were
treated sufficiently and all patients recovered without permanent significant morbidity.
Conclusion: Treatment with the p64MW-HPC is safe and feasible and achieves
good early aneurysm occlusion rates in the proximal intracranial circulation, which are
comparable to those of well-established FDS. Sudden interruption of DAPT in the
early post-interventional phase can cause in-stent thrombosis despite the HPC surface
modification. Deliverability via the 0.021” microcatheter facilitates treatment in challenging
vascular anatomies
Endovascular Treatment of Intracranial Aneurysms in Small Peripheral Vessel Segments—Efficacy and Intermediate Follow-Up Results of Flow Diversion With the Silk Vista Baby Low-Profile Flow Diverter
Background and Purpose: Low-profile flow diverter stents (FDS) quite recently
amended peripheral segments as targets for hemodynamic aneurysm treatment;
however, reports on outcomes, especially later than 3 months, are scarce. This study
therefore reports our experience with the novel silk vista baby (SVB) FDS and respective
outcomes after 8 and 11 months with special respect to specific adverse events.
Materials and Methods: Forty-four patients (mean age, 53 years) harboring 47
aneurysms treated with the SVB between June 2018 and December 2019 were included
in our study. Clinical, procedural, and angiographic data were collected. Follow-ups were
performed on average after 3, 8, and 11 months, respectively. Treatment effect was
assessed using the O’Kelly Marotta (OKM) grading system.
Results: Overall, angiographic follow-ups were available for 41 patients/45 aneurysms.
Occlusion or significant reduction in aneurysmal perfusion (OKM: D1, B1–B3 and
A2–A3) was observed in 98% of all aneurysms after 8 months. Only 2% of the treated
aneurysms remained morphologically unaltered and without an apparent change in
perfusion (OKM A1). Adverse events in the early post-interventional course occurred
in seven patients; out of them, mRS-relevant morbidity at 90 days related to FDS
treatment was observable in two patients. One death occurred in the context of
severe SAH related to an acutely ruptured dissecting aneurysm of the vertebral artery.
Conclusion: The SVB achieves sufficient occlusion rates of intracranial aneurysms
originating from peripheral segments, which are comparable to prior established
conventional FDS with acceptably low complication rates. However, alteration of a
hemodynamic equilibrium in distal localizations requires special attention to prevent
ischemic events
Nimodipine vs. Milrinone – Equal or Complementary Use? A Retrospective Analysis
Background: Cerebral vasospasm (CVS) continues to account for high morbidity and
mortality in patients surviving the initial aneurysmal subarachnoid hemorrhage (SAH).
Nimodipine is the only drug known to reduce delayed cerebral ischemia (DCI), but it
is believed not to affect large vessel CVS. Milrinone has emerged as a promising option.
Our retrospective study focused on the effectiveness of the intra-arterial application of
both drugs in monotherapy and combined therapy.
Methods: We searched for patients with aneurysmal SAH, angiographically confirmed
CVS, and at least one intra-arterial pharmacological angioplasty. Ten defined vessel
sections on angiograms were assessed before and after vasodilator infusion. The
improvement in vessel diameters was compared to the frequency of DCI-related cerebral
infarction before hospital discharge and functional outcome reported as the modified
Rankin Scale (mRS) score after 6 months.
Results: Between 2014 and 2021, 132 intra-arterial interventions (144 vascular
territories, 12 bilaterally) in 30 patients were analyzed for this study. The vasodilating
effect of nimodipine was superior to milrinone in all intradural segments. There was
no significant intergroup difference concerning outcome in mRS (p = 0.217). Only
nimodipine or the combined approach could prevent DCI-related infarction (both 57.1%),
not milrinone alone (87.5%). Both drugs induced a doubled vasopressor demand due to
blood pressure decrease, but milrinone alone induced tachycardia.
Conclusions: The monotherapy with intra-arterial nimodipine was superior to milrinone.
Nimodipine and milrinone may be used complementary in an escalation scheme with the
administration of nimodipine first, complemented by milrinone in cases of severe CVS.
Milrinone monotherapy is not recommended
Delayed Stroke after Aneurysm Treatment with Flow Diverters in Small Cerebral Vessels: A Potentially Critical Complication Caused by Subacute Vasospasm
Flow diversion (FD) is a novel endovascular technique based on the profound alteration
of cerebrovascular hemodynamics, which emerged as a promising minimally invasive therapy for
intracranial aneurysms. However, delayed post-procedural stroke remains an unexplained concern.
A consistent follow-up-regimen has not yet been defined, but is required urgently to clarify the
underlying cause of delayed ischemia. In the last two years, 223 patients were treated with six
different FD devices in our center. We identified subacute, FD-induced segmental vasospasm (SV) in
36 patients as a yet unknown, delayed-type reaction potentially compromising brain perfusion to a
critical level. Furthermore, 86% of all patients revealed significant SV approximately four weeks after
treatment. In addition, 56% had SV with 25% stenosis, and 80% had additional neointimal hyperplasia.
Only 13% exhibited SV-related high-grade stenosis. One of those suffered stroke due to prolonged
SV, requiring neurocritical care and repeated intra-arterial (i.a.) biochemical angioplasty for seven
days to prevent territorial infarction. Five patients suffered newly manifested, transient hemicrania
accompanying a compensatorily increased ipsilateral leptomeningeal perfusion. One treated vessel
obliterated permanently. Hence, FD-induced SV is a frequent vascular reaction after FD treatment,
potentially causing symptomatic ischemia or even stroke, approximately one month post procedure.
A specifically early follow-up-strategy must be applied to identify patients at risk for ischemia,
requiring intensified monitoring and potentially anti-vasospastic treatment
Segment Occlusion vs. Reconstruction—A Single Center Experience With Endovascular Strategies for Ruptured Vertebrobasilar Dissecting Aneurysms
Objective: Ruptured dissecting aneurysms of the intracranial vertebral arteries exhibit an extraordinarily high risk for morbidity and mortality and are prone to re-rupture. Therefore, early treatment is mandatory to induce stagnation of the critical dynamic mural process. Appropriate endovascular approaches are segment sacrifice and reconstruction, however, both carry specific risks and benefits. To date most studies discuss only one of these approaches and focus on one specific device or technique. Therefore, our study aimed to present our experiences with both techniques, providing a considered approach on when to perform endovascular reconstruction or sacrifice.Materials and Methods: We retrospectively reviewed patients with subarachnoid hemorrhage in our database, suffering from dissecting aneurysms of the intradural vertebral arteries and treated endovascularly in the acute setting. A total of 16 cases were included. Clinical history, radiologic findings and outcomes were analyzed.Results: In 7 patients a reconstructive approach was chosen with 4 of them receiving stent-assisted coiling as primary strategy. One of the 7 patients suffered early re-bleeding due to progression of the dissection and therefore treatment was augmented with implantation of 2 flow diverters. The remaining 2 patients were primarily treated with flow diverters in telescoping technique. In 9 patients a deconstructive approach was followed: 6 patients were treated with proximal coil-occlusion of the V4 segment, 3 patients received distal coiling of the V4 segment. Two patients died (GOS 1) in the subacute stage due to sequelae of recurrent episodes of raised intracranial pressure and parenchymal hemorrhage. Two patients kept severe disability (GOS 3), six patients had moderate disability (GOS 4) and seven patients showed full recovery (GOS 5). None of the patients suffered from a procedural or postprocedural ischemic stroke.Conclusions: In patients with good collateral vascularization, proximal, or distal partial segment sacrifice via with endovascular coil occlusion seems to yield the best risk-benefit ratio for treatment of ruptured dissecting V4 aneurysms, especially since no continued anticoagulation is required and possibly essential surgery remains feasible in this scenario. If possible, PICA occlusion should be avoided—although even proximal PICA occlusion can become necessary, when weighing against the risk of an otherwise untreated ruptured V4 dissecting aneurysm. Contrarily, if the dominant V4 segment is affected, the hemodynamic asymmetry prohibits occlusion and necessitates reconstruction of the respective segment. For this, implants with high metal coverage treating the entire affected segment appear to be the most promising approach
Flow Diversion for Reconstruction of Intradural Vertebral Artery Dissecting Aneurysms Causing Subarachnoid Hemorrhage—A Retrospective Study From Four Neurovascular Centers
Objective: Dissecting aneurysms (DAs) of the vertebrobasilar territory manifesting
with subarachnoid hemorrhage (SAH) are associated with significant morbi-mortality,
especially in the case of re-hemorrhage. Sufficient reconstruction of the affected vessel
is paramount, in particular, if a dominant vertebral artery (VA) is impacted. Reconstructive
options include stent-assisted coiling and flow diversion (FD). The latter is technically less
challenging and does not require catheterization of the fragile aneurysm. Our study aims
to report a multicentric experience with FD for reconstruction of DA in acute SAH.
Materials and Methods: This retrospective study investigated 31 patients (age: 30–78
years, mean 55.5 years) who had suffered from SAH due to a DA of the dominant VA.
The patients were treated between 2010 and 2020 in one of the following German
neurovascular centers: University Hospital Leipzig, Katharinenhospital Stuttgart, BG
Hospital Bergmannstrost Halle/Saale, and Heinrich-Braun-Klinikum Zwickau. Clinical
history, imaging, implanted devices, and outcomes were reviewed for the study.
Results: Reconstruction with flow-diverting stents was performed in all cases. The
p64 was implanted in 14 patients; one of them required an additional balloon expandable stent to reconstruct severe stenosis in the target segment. One case
demanded additional liquid embolization after procedural rupture, and in one case,
p64 was combined with a PED. Further 13 patients were treated exclusively with
the PED. The p48MW-HPC was used in two patients, one in combination with two
additional Silk Vista Baby (SVB). Moreover, one patient was treated with a single SVB,
one with a SILK+. Six patients died [Glasgow Outcome Scale (GOS) 1]. Causes of
death were periprocedural re-hemorrhage, thrombotic occlusion of the main pulmonary
artery, and delayed parenchymal hemorrhage. The remaining three patients died in the
acute–subacute phase related to the severity of the initial hemorrhage and associated
comorbidities. One patient became apallic (GOS 2), whereas two patients had severe
disability (GOS 3) and four had moderate disability (GOS 4). Eighteen patients showed a
complete recovery (GOS 5).
Conclusion: Reconstruction of VA-DA in acute SAH with flow-diverting stents is a
promising approach. However, the severity of the condition is reflected by high overall
morbi-mortality, even despite technically successful endovascular treatment
Reference Values of Cerebral Artery Diameters of the Anterior Circulation by Digital Subtraction Angiography: A Retrospective Study
A threshold-based classification of cerebral vasospasm needs reference values for intracranial vessel diameters on digital subtraction angiography (DSA). We aimed to generate adjusted reference values for this purpose by retrospectively analyzing angiograms and potential influencing factors on vessel diameters. Angiograms of the anterior circulation were evaluated in 278 patients aged 18–81 years. The vessel diameters of 453 angiograms (175 bilateral) were gathered from nine defined measuring sites. The effect sizes of physical characteristics (i.e., body weight and height, body mass index, gender, age, and cranial side) and anatomical variations were calculated with MANOVA. Segments bearing aneurysms were excluded for the calculation of reference values. Adjusted vessel diameters were calculated via linear regression analysis of the vessel diameter data. Vessel diameters increased with age and body height. Male and right-sided vessels were larger in diameter. Of the anatomical variations, only the hypoplastic/aplastic A1 segment had a significant influence (p < 0.05) on values of the anterior cerebral artery and the internal carotid artery with a small effect size (|ω2| > 0.01) being excluded from the reference values. We provide gender-, age-, and side-adjusted reference values and nomograms of arterial vessel diameters in the anterior circulation
Diffusion-Weighted MRI Reflects Proliferative Activity in Primary CNS Lymphoma.
PURPOSE:To investigate if apparent diffusion coefficient (ADC) values within primary central nervous system lymphoma correlate with cellularity and proliferative activity in corresponding histological samples. MATERIALS AND METHODS:Echo-planar diffusion-weighted magnetic resonance images obtained from 21 patients with primary central nervous system lymphoma were reviewed retrospectively. Regions of interest were drawn on ADC maps corresponding to the contrast enhancing parts of the tumors. Biopsies from all 21 patients were histologically analyzed. Nuclei count, total nuclei area and average nuclei area were measured. The proliferation index was estimated as Ki-67 positive nuclei divided by total number of nuclei. Correlations of ADC values and histopathologic parameters were determined statistically. RESULTS:Ki-67 staining revealed a statistically significant correlation with ADCmin (r = -0.454, p = 0.038), ADCmean (r = -0.546, p = 0.010) and ADCmax (r = -0.515, p = 0.017). Furthermore, ADCmean correlated in a statistically significant manner with total nucleic area (r = -0.500, p = 0.021). CONCLUSION:Low ADCmin, ADCmean and ADCmax values reflect a high proliferative activity of primary cental nervous system lymphoma. Low ADCmean values-in concordance with several previously published studies-indicate an increased cellularity within the tumor