Safety of intracranial venous stenting in patients with nickel allergy

BACKGROUND

Nickel hypersensitivity is the most common metal related allergy. Nickel containing alloys are frequently used in endovascular devices. The use of intracranial stents in patients with nickel hypersensitivity appears to be safe, but these small series only evaluated arterial stent placement. This case series aimed to assess the safety of intracranial venous stent placement in patients with documented nickel allergy.

METHODS

In this retrospective multicenter case series, patients with idiopathic intracranial hypertension and documented nickel allergy underwent treatment with a permanently implanted nickel containing stent in the dural venous sinuses.

RESULTS

Nine patients with nickel allergy were included. All patients reported clinical improvement in their idiopathic intracranial hypertension symptoms. Of the five patients who had follow-up intracranial venous imaging, all stents remained patent. No patients experienced intraoperative, postoperative, or long term procedure related complications, with follow-up ranging from 1.8 weeks to 49.1 months.

CONCLUSION

In this limited case series, the use of nickel containing stents in intracranial venous sinuses in patients with nickel allergy did not result in any allergic reaction or adverse outcome.

Longitudinal radiological follow-up of individual level non-ischemic cerebral enhancing lesions following endovascular aneurysm treatment

BACKGROUND

Non-ischemic cerebral enhancing (NICE) lesions following aneurysm endovascular therapy are exceptionally rare, with unknown longitudinal evolution.

OBJECTIVE

To evaluate the radiological behavior of individual NICE lesions over time.

METHODS

Patients included in a retrospective national multicentric inception cohort were analyzed. NICE lesions were defined, using MRI, as delayed onset punctate, nodular, or annular foci enhancements with peri-lesion edema, distributed in the vascular territory of the aneurysm treatment, with no other confounding disease. Lesion burden and the longitudinal behavior of individual lesions were assessed.

RESULTS

Twenty-two patients were included, with a median initial lesion burden of 36 (IQR 17-54) on the first MRI scan. Of the 22 patients with at least one follow-up MRI scan, 16 (73%) had new lesions occurring mainly within the first 200 weeks after the date of the procedure. The median number of new lesions per MRI was 6 (IQR 2-16). Among the same 22 patients, 7 (32%) had recurrent lesions. The median persistent enhancement of a NICE lesion was 13 weeks (IQR 6-30). No factor was predictive of early regression of enhancement activity with lesion regression kinetics mainly being patient-dependent.

CONCLUSIONS

The behavior of individual NICE lesions was found to be highly variable with an overall patient-dependent regression velocity.

Delayed Enhancing White Matter Lesions, a Rare Complication After Stent-Assisted Coil Embolization: A Case Report

BACKGROUND

Delayed enhancing white matter lesions are a rare complication that develops after endovascular treatment of cerebral aneurysms, the etiology of which remains unclear.

METHODS AND RESULTS

We present a 52-year-old female patient who was symptomatic with a seizure-like condition and showed reversible cranial parenchymal changes with high-dose cortisone treatment after endovascular stent-assisted coil embolization for an unruptured aneurysm in the internal cerebral artery.

CONCLUSIONS

Clinicians should be alert to this rare complication and should follow patients for a long time due to its fluctuating and long-term course.

Possible Delayed Foreign Body Reactions against Titanium Clips and Coating Materials after Unruptured Cerebral Aneurysm Surgery

Delayed foreign body reactions to either or both clipping and coating materials have been reported in several small series; however, studies in the titanium clip era are scarce. This study aims to survey the contemporary status of such reactions to titanium clips and coating materials. Among patients who received a total of 2327 unruptured cerebral aneurysmal surgeries, 12 developed delayed intraparenchymal reactions during outpatient magnetic resonance imaging (MRI) follow-up. A retrospective investigation was conducted. The patients' average age was 58.6 (45-73) years, and 11 were women. The aneurysms were located in the middle cerebral artery (n = 7), internal carotid artery (n = 4), or anterior communicating artery (AComA, n = 1). In 10 patients, additional coating with tiny cotton fragments was applied to the residual neck after clipping with titanium clips; however, only the clipping with titanium clips was performed in the remaining two. The median time from surgery to diagnosis was 4.5 (0.3-60) months. Seven (58.3%) patients were asymptomatic, and three developed neurological deficits. MRI findings were characterized by a solid- or rim-enhancing lobulated mass adjacent to the clip with surrounding parenchymal edema. In 11 patients, the lesions reduced in size or disappeared; however, in one patient, an AComA aneurysm was exacerbated, necessitating its removal along with optic nerve decompression. In conclusion, cotton material is a strongly suspected cause of delayed foreign body reactions, and although extremely rare, titanium clips alone may also induce such a reaction. The prognosis is relatively good with steroid therapy; however, caution is required when the aneurysm is close to the optic nerve, as in AComA aneurysms.

Delayed Leucoencephalopathy as a Complication after Endovascular Therapy of Intracranial Aneurysms-A Case Series

We describe the clinical presentation, radiological findings, treatment and outcomes of three patients with delayed leukoencephalopathy occurring after endovascular treatment (EVT) for cerebral aneurysms-a rare, albeit recurring, complication. The symptoms occurred 6 to 12 months following the EVT of the cerebral aneurysm. Characteristic imaging findings included high-signal changes on T2 images in the white matter without diffusion restriction predominantly at the distribution of the vascular territory of the catheterized arteries, coupled with patchy gadolinium enhancement or low susceptibility weighted imaging (SWI) signals within the white-matter lesions. Steroid pulse therapy is the treatment of choice and promptly improves clinical and imaging findings. Tapering or cessation of steroids may result in clinical and imaging relapses; close- and long-term follow-up for patients presenting this complication is warranted.

Incidence, clinical spectrum, and immunotherapy of non-ischemic cerebral enhancing lesions after endovascular therapy

Background:

Symptomatic and asymptomatic delayed non-ischemic cerebral enhancing (NICE) lesions in magnetic resonance imaging (MRI) have been reported as a rare complication after endovascular therapy (EVT) in recent years with incidence rates between 0.05% and 0.9% in most studies. Information on long-term clinical course and immunotherapies is scarce or has not been reported in detail in the literature. Objective: Aims of our study were to assess the incidence of NICE lesions in patients after cerebral EVT over a period of more than 12 years, describe clinical and EVT characteristics, and immunotherapies applied.

Methods:

A retrospective chart review of all patients treated by endovascular therapy for symptomatic or asymptomatic aneurysms at the University Hospital of Augsburg from May 1, 2008 to December 31, 2020 was performed. Patients were identified retrospectively and followed-up prospectively where appropriate. In addition, one case treated at another institution was included.

Results:

Five out of 746 patients, 0.67%, developed NICE lesions after EVT, all with non-ruptured aneurysms and all symptomatic upon detection of NICE lesions by MRI. In total, the disease course of 6 female patients is reported. Symptoms occurred after a mean time of 15 days (±13.42, SD) after EVT with headache (6/6 patients), focal neurological signs (6/6 patients), epileptic seizures (2/6 patients) and cognitive deficits (3/6 patients). All 6 patients received glucocorticosteroids (GCS), 1/6 azathioprine (AZA), 4/6 mycophenolate mofetil (MMF), 1/6 methotrexate (MTX), 1/6 rituximab (RTX), 2/6 cyclophosphamide (CYC) and 3/6 tocilizumab (TCZ). A treatment response could be observed for GCS, TCZ and MMF (in two of four cases), RTX and AZA did not result in disease stabilization.

Conclusions:

Delayed NICE lesions are a rare complication after EVT, requiring immunotherapies in all patients reported here. Physicians should be aware of this disorder in case of new symptoms or contrast enhancing lesions after EVT.

Delayed Leukoencephalopathy and Foreign Body Reaction After Endovascular Treatment in Patients With Intracranial Aneurysms and Aneurysmal Subarachnoid Hemorrhage-A Systematic Review of the Literature

Background: Delayed leukoencephalopathy and foreign body reaction are rare complications after endovascular treatment of intracranial aneurysms. However, cases are increasingly being described, given the rising case numbers and complexity.

Methods: Clinical presentation, differentials, diagnostics, treatment, and formerly published data were reviewed in light of available cases. A systematic search of the literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.

Results: This article provides an extensive literature review of previously described cases, and discusses the causes and management of this rare and delayed complication by referring to 17 articles on this topic, with a total of 50 cases with sufficient data in the literature. Furthermore, we present the case of a 53-year-old female patient with subarachnoid hemorrhage from a large anterior communicating artery aneurysm with tortuous cervical vessels who was treated with endovascular coiling and has suffered delayed leukoencephalopathy 6 weeks after discharge. Diagnostics, treatment, and clinical course of this rare complication are presented on this case and based on formerly published literature. The patient timely recovered under high dose corticosteroid treatment and follow up MRI showed almost complete remission of the described lesions within 10 days in accordance with previously published data.

Conclusion: Foreign body reaction might result in delayed leukoencephalopathy, especially following complex endovascular aneurysm treatment. Early high dose followed by low dose ongoing corticosteroid treatment might result in timely remission.

Nickels and tines: the myth of nickel allergy in intracranial stents

BACKGROUND

Most intracranial stents contain nickel alloy, and nickel allergy or hypersensitivity is common. Neurological injury following endovascular treatment with a nickel containing intracranial stent has been reported in patients with purported nickel allergy, but it is unclear whether these reactions represent true nickel hypersensitivity. We quantified nickel release from commonly used intracranial stents to investigate whether such stents should be avoided in patients with nickel allergy.

METHODS

We examined nickel release from seven commonly used intracranial stents: Enterprise, LVIS Jr, Neuroform, Wingspan, Zilver, Pipeline Flex Embolization Device, and Surpass Evolve. We incubated each stent in human plasma-like media for 30 days. Dimethylglyoxime (DMG) spot testing was performed on each stent to detect released nickel at 0 and 30 days. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) was then used to quantify the nickel concentration of the media at 30 days. Nickel currency and nickel standard for atomic absorption spectrometry were used as positive controls.

RESULTS

DMG spot tests indicated nickel release only from nickel currency at 0 and 30 days of incubation. No nickel release was detected from any stent at 30 days using ICP-OES.

CONCLUSIONS

Nickel release from commonly used intracranial stents is negligible. These results suggest that previously reported hypersensitivity to these stents may be misattributed to nickel allergy, and that patients with nickel allergy may be safely treated with select nickel-containing stents.

Nickel hypersensitivity and endovascular devices: a systematic review and meta-analysis

OBJECTIVE

Nickel allergy is common; endovascular specialists are often confronted with nickel allergic patients ahead of the implantation of endovascular devices, many of which are nickel-containing. Our aim was to elucidate whether nickel hypersensitivity is significantly associated with worse or adverse outcomes after placement of a nickel-containing endovascular device.

METHODS

Inclusion criteria were: endovascular and transcatheter procedures for coronary, structural heart, neurovascular and peripheral vascular pathology involving nickel-allergic patients. All adverse outcomes were included as defined by included studies. A systematic review and meta-analysis were undertaken using a random-effects model. Searches of MEDLINE and EMBASE were conducted for articles published 1947-2019.

RESULTS

190 records were identified, 78 articles were included for qualitative synthesis and 15 met criteria for meta-analysis. Patch-test confirmed nickel allergy was associated with an increased risk of adverse outcomes following implantation of a nickel-containing endovascular device (n=14 articles, 1740 patients; OR 2.61, 95% CI 1.41 to 4.85). This finding further was observed in coronary (n=12 articles, 1624 patients; OR 1.94, 95% CI 1.16 to 3.23) and structural heart subgroups (n=2 articles, 83 patients; OR 52.28, 95% CI 1.31 to 2079.14), but not in the neurovascular subgroup (n=1 article, 33 patients; OR 3.04, 95% CI 0.59 to 15.72) or with a patient-reported history of nickel allergy (n=2 articles, 207 patients; OR 2.14, 95% CI 0.23 to 19.70).

CONCLUSIONS

Patch-tested nickel allergy is associated with an increased risk of adverse outcomes following endovascular device implantation and alternative treatment options should be considered. Specialists faced with patients' self-reporting nickel allergy should consider proceeding to diagnostic patch-testing.

Delayed recurrent enhancing white matter lesions complicating coiling of intracranial aneurysm

BACKGROUND AND PURPOSE

In recent years, the use of coiling has gained increased popularity for the treatment of intracranial aneurysms, and stroke physicians are confronted with rare pathologies associated with this relatively new and evolving treatment method, such as embolization of pieces of the polymeric filaments from the coils and a subsequent inflammatory response. In particular, white matter enhancing lesions are a rare complication after aneurysm endovascular therapy (EVT), suggesting a foreign body reaction to shedding of hydrophilic coating from the endovascular devices into the blood stream. The description of such a case aims to raise the clinicians' awareness of the symptomatic delayed and recurring inflammatory changes that may occur after endovascular aneurysmal treatment with the use of coiling devices.

CASE DESCRIPTION

A 64-year-old woman underwent coiling of a ruptured right posterior communicating artery aneurysm. She was asymptomatic after EVT. One year later, she presented with headache, acoustic hallucinations, paresthesias and left arm weakness. Brain magnetic resonance imaging (MRI) revealed multiple enhancing white matter lesions in the right hemisphere. She was treated with pulse intravenous methylprednisolone, followed by oral prednisolone; all clinical symptoms resolved and imaging findings improved substantially. Two years after tapering the steroids, follow-up symptoms recurred and repeat brain MRI revealed new enhancing white matter lesions.

DISCUSSION AND CONCLUSIONS

There is an increasing number of similar reports of enhancing white matter lesions after coiling of intracranial aneurysms, with the incidence estimated to be between 0.5% and 2.3% in different cohort studies. Close monitoring for the appearance of new neurologic symptoms that could suggest delayed brain reactivity should be recommended.

Medical treatment of polymeric cerebral granulomatous reactions following endovascular procedures

BACKGROUND

Endovascular procedures are standard of care for an increasing range of cerebrovascular diseases. Many endovascular devices contain plastic and are coated with a hydrophilic polymer which has been rarely described to embolize, resulting in distal granulomatous inflammatory lesions within the vascular territory.

METHODS

We reviewed three cases of cerebral granulomatous reactions that occurred after endovascular intervention for internal carotid aneurysms. The patient procedure details, presentation, relevant investigations, and treatment course are described. We also provide a literature review on endovascular granulomatous reactions.

RESULTS

These three cases represent the largest biopsy proven series of cerebral granulomatosis following endovascular intervention. We highlight the variable clinical presentation, with two of the three cases having an unusually delayed onset of up to 4 years following the intervention. We show the characteristic histological findings of granulomatous lesions with foreign body material consistent with a type IV reaction, radiological abnormalities of enhancing lesions within the vascular territory of the intervention, and the requirement of prolonged immunosuppression for maintenance of clinical remission, with two of the three patients requiring a corticosteroid sparing agent. In comparison with the available literature, in addition to hydrophilic gel polymer, we discuss that plastic from the lining of the envoy catheter may be a source of embolic material. We also discuss the recommendations of the Food and Drug Administration and the implementation of novel biomaterials for the prevention of these reactions in the future.

CONCLUSIONS

There is a need for increased awareness of this severe complication of cerebral endovascular procedures and further longitudinal studies of its prevalence, optimal management and preventative measures.

Risk of Seizures after Endovascular Management of Ruptured Intracranial Aneurysms: A Systematic Review and Meta-analysis

Seizures in aneurysmal subarachnoid haemorrhage (aSAH) have been described secondary to SAH, changes in cortical function, vasospasm and as a result of treatment effects. Seizures are one of the important clinical determinants in neurological outcome of aSAH. Various studies support the notion of less risk of future seizures in endovascular treatment as compared to the microsurgical clipping, yet there is no conclusive evidence in favour or against the seizure occurrence in aSAH patients after endovascular treatment as compared to the microsurgical treatment. To carry out a systematic review and meta-analysis of the risk of seizures after endovascular management (coiling) of ruptured intracranial aneurysms. A literature search was performed in electronic database of PubMed, MEDLINE, Embase, and Scopus from inception to February 2020, using the terms Seizure, Intracranial aneurysms, embolization, with no constraints applied. Data were pooled using a random-effect model, results were abstracted as odds ratios (ORs) and 95% confidence interval (CI), and heterogeneity was reported as Chi-square. Five studies involving 3,077 patients were included in the meta-analysis. After endovascular management of aSAH, seizure risk was increased by a worse clinical severity (World Federation of Neurosurgery scale or Hunt and Hess) (OR, 3.34; 95% CI, 2.69–4.16; p<0.00001), severe vasospasm (OR, 2.20; 95% CI, 1.67–2.92; p<0.00001), cerebral infarction (OR, 5.19; 95% CI, 3.23–8.35; p<0.00001), and cerebral edema (OR, 1.79; 95% CI, 1.37–2.34; p<0.0000). Worse clinical severity, vasospasm, cerebral infarction and cerebral oedema are significant risk factors for the development of seizures after endovascular intervention in aSAH. The mechanism for this correlation is not clear.