Incidence of contrast-induced neurotoxicity following endovascular treatment of unruptured intracranial aneurysms: a single-centre cohort study.

BACKGROUND: Contrast-induced neurotoxicity (CIN) is a recognised complication of endovascular procedures and has been increasingly observed in recent years. Amongst other clinical gaps, the precise incidence of CIN is unclear, particularly following intracranial interventional procedures. METHODS: A retrospective study of consecutive patients undergoing elective endovascular treatment of unruptured intracranial aneurysms (UIAs) was performed. Patients with previously ruptured aneurysms were excluded. The primary aim of this study was to determine the incidence of CIN following endovascular UIA treatment. Our secondary aim was to isolate potential predictive factors for developing CIN. RESULTS: From 2017 to 2023, a total of 158 patients underwent endovascular UIA treatment, with a median age of 64 years (IQR: 54-72), and 70.3% of female sex. Over the study period, the crude incidence of CIN was 2.5% (95% CI: 0.7 - 6.4%). The most common clinical manifestation of CIN was confusion (75%) and seizures (50%). Statistical analysis was conducted, and prolonged procedural duration was found be significantly associated with developing CIN (OR 12.55; p = 0.030). CONCLUSION: Clinicians should be aware of the risk of CIN following endovascular neurointervention, particularly following technically challenging cases resulting in prolonged procedural time.

Facilitating complete resection of intrinsic motor cortex glioma with titration of high-frequency cortico-subcortical mapping train count informed by navigated transcranial magnetic stimulation: illustrative case.

BACKGROUND: The dilemma of neuro-oncological surgery involving suspected eloquent cortex is to maximize the extent of resection while minimizing neurological morbidity, referred to as the "onco-functional balance." Diffuse lower-grade gliomas are capable of infiltrating or displacing neural function within cortical regions and subcortical white matter tracts, which can render classical anatomic associations of eloquent function misleading. OBSERVATIONS: This study employed presurgical navigated transcranial magnetic stimulation (nTMS) to determine the motor eloquence of a diffuse lower-grade glioma at the superior frontal gyrus extending and intrinsic to the primary motor cortex in a 45-year-old female. Positive nTMS findings were confirmed intraoperatively with high-frequency direct cortico-subcortical stimulation (HF-DCS). Modification of the HF-DCS train count from train-of-five to train-of-two permitted resection beyond classic anatomical boundaries and conventional HF-DCS safe stopping criteria. LESSONS: Anatomical correlates of function can inaccurately inform the surgical management of diffuse lower-grade glioma, which represents the utmost opportunity for progression-free survival. Integrating an individually tailored nTMS-DCS surgical strategy contributed to complete resection, negating the requirement for adjuvant therapy. Serial nTMS follow-up may assist with the characterization of tumor-induced functional reorganization. https://thejns.org/doi/10.3171/CASE24197.

Rotation from methadone to buprenorphine using a micro-dosing regime in patients with opioid use disorder and serious mental illness: A case series.

INTRODUCTION: Inducting buprenorphine from methadone has traditionally involved initial opioid withdrawal, with risk of mental state deterioration in patients with serious mental illness (SMI). Micro-dosing of buprenorphine, with small incremental doses, is a novel off-label approach to transitioning from methadone and does not require a period of methadone abstinence. Given the limited literature about buprenorphine microdosing, we aimed to evaluate the feasibility and safety of inducting buprenorphine in a series of patients on methadone with SMI. METHODS: For this retrospective case series, we reviewed the records of 16 patients with SMI at a Melbourne addiction treatment centre, from January 2021 to July 2022, who transitioned via micro-dosing, from high-dose methadone (>30 mg) to buprenorphine and depot-buprenorphine. Psychiatric diagnoses, mental state, other substance withdrawal, transfer success, transition time, opioid withdrawal symptoms and overall patient experience were collected via objective and subjective reporting. RESULTS: Methadone to buprenorphine transfer was completed by 88% of patients. Mental health measures remained stable with the exception of mildly increased anxiety. Median transfer time was 6.5 days for inpatients, 9 days for mixed setting and 10 days for outpatients. Most patients (93%) rated their experience 'manageable' reporting mild withdrawal symptoms. One patient met study criteria for precipitated withdrawal. DISCUSSION AND CONCLUSIONS: This retrospective case series provides evidence that the use of a micro-dosing buprenorphine induction for methadone to buprenorphine transitions, including to depot-buprenorphine, has negligible risk, is tolerated by patients with SMI and is unlikely to precipitate an exacerbation of their mental illness.

Neuroradiological features of contrast-induced neurotoxicity: A systematic review and pooled analysis.

BACKGROUND: Contrast-induced neurotoxicity (CIN), is an increasingly recognised complication of endovascular procedures, presenting as a spectrum of neurological symptoms that mimic ischaemic stroke. The diagnosis of CIN remains a clinical challenge, and stereotypical imaging findings are not established. This study was conducted to characterise the neuroimaging findings in patients with CIN, to raise diagnostic awareness and improve decision making. METHODS: We performed a systematic review of PubMed and Embase databases from inception (1946/1947) to June 2023 for reports of CIN following administration of iodinated contrast media. Studies with a final diagnosis of CIN, which provided details of neuroimaging were included. All included cases were pooled and descriptive analysis was conducted. RESULTS: A total of 84 patients were included, with a median age of 64 years. A large proportion of patients had normal imaging (CT 40.8 %, MRI 53.1 %). CT abnormalities included cortical/subarachnoid hyperattenuation (42.1 %), cerebral oedema/sulcal effacement (26.3 %), and loss of grey-white differentiation (7.9 %). Frequently reported MRI abnormalities included brain parenchymal MRI signal change (40.8 %) and cerebral oedema (12.2 %), most commonly observed on FLAIR sequences (26.5 %). Characterisation of imaging findings according to anatomical location and clinical symptoms has been conducted. CONCLUSIONS: Neuroimaging is an essential part of the diagnostic workup of CIN. Analysis of the anatomical location and laterality of imaging abnormalities may suggest relationship between radiological features and actual clinical symptoms, although this remains to be confirmed with dedicated study. Radiological abnormalities, particularly CT, appear to be transient and reversible in most patients.

Clinical management of contrast-induced neurotoxicity: a systematic review.

BACKGROUND: Contrast-induced neurotoxicity (CIN) is an increasingly recognised complication following endovascular procedures utilising contrast. It remains poorly understood with heterogenous clinical management strategies. The aim of this review was to identify commonly employed treatments for CIN to enhance clinical decision making. METHODS: A systematic search of Embase (1947-2022) and Medline (1946-2022) was conducted. Articles describing (i) patients with a clinical diagnosis of CIN, (ii) with radiological exclusion of other pathologies, (iii) detailed report of treatments, and (iv) discharge outcomes, were included. Data relating to demographics, procedure, symptoms, treatment and outcomes were extracted. RESULTS: A total of 73 patients were included, with a median age of 64 years. The most common procedures were cerebral angiography (42.5%) and coronary angiography (42.5%), and the median volume of contrast administered was 150 ml. The most common symptoms were cortical blindness (38.4%) and reduced consciousness (28.8%), and 84.9% of patients experienced complete resolution at the time of discharge. Management included intravenous fluids to dilute contrast in the cerebrovasculature (54.8%), corticosteroids to reduce blood-brain barrier damage (47.9%), antiseizure (16.4%) and sedative (16.4%) medications. Mannitol (13.7%) was also utilised to reduce cerebral oedema. Intensive care admission was required for 19.2% of patients. No statistically significant differences were observed between treatment and discharge outcomes. CONCLUSIONS: The clinical management of CIN should be considered on a patient-by-patient basis, but may consist of aggressive fluid therapy alongside corticosteroids, as well as other supportive therapy as required. Further examination of CIN management is required to define best practice.

Pathophysiology of Contrast-Induced Neurotoxicity: A Narrative Review of Possible Mechanisms.

BACKGROUND: Contrast-induced neurotoxicity (CIN) is an increasingly observed event following the administration of iodinated contrast. It presents as a spectrum of neurological symptoms that closely mimic ischaemic stroke, however, CIN remains a poorly understood clinical phenomenon. An appreciation of the underlying pathophysiological mechanisms is essential to improve clinical understanding and enhance decision-making. METHODS: A broad literature search of Medline (1946 to December 2022) and Embase (1947 to December 2022) was conducted. Articles discussing the pathophysiology of CIN were reviewed. SUMMARY: The pathogenesis of CIN appears to be multifactorial. A key step is likely blood-brain barrier (BBB) breakdown due to factors including ischaemic stroke, uncontrolled hypertension, and possibly contrast agents themselves, among others. This is followed by passage of contrast agents across the BBB, leading to chemotoxic sequelae on neural tissue. KEY MESSAGES: This review provides a clinically oriented review on the pathophysiology of CIN to enhance knowledge and improve decision-making among clinicians.

Current knowledge and perspectives of contrast-induced neurotoxicity: A survey of Australian clinicians.

BACKGROUND: Contrast-induced Neurotoxicity (CIN) is an increasingly recognised complication following endovascular procedures. It remains a relatively unexplored clinical entity, and we sought to characterise clinician perspectives towards CIN, as well as identify gaps in knowledge and provide directions for future research. METHODS: An online survey was distributed to members of the Australian and New Zealand Society of Neuroradiology, as well as several Australian tertiary hospitals. Questions related to clinical exposure to CIN, diagnosis, management and pathophysiology were explored. Descriptive analysis was conducted on survey responses, and statistical analysis was performed using Chi-square and Fisher's exact test as appropriate. RESULTS: A total of 95 survey responses were recorded (26.8% response rate). Only 28.4% of respondents were comfortable in diagnosing CIN, and even fewer (24.2%) were comfortable in independently managing CIN patients. Based on clinician opinion, symptoms including impaired consciousness and cortical blindness were thought to be most associated with CIN, whilst the radiological findings of parenchymal oedema and cortical enhancement were considered to be most indicative of CIN. Most clinicians agreed that further investigation is required related to pathophysiology (86.3%), diagnosis (83.2%), and treatment (82.1%). CONCLUSION: CIN is a poorly understood complication following endovascular procedures. Significant gaps in clinical understanding are evident, and further investigation is vital to improve diagnosis and management.

Amyloid-ß (Aß)-Related Cerebral Amyloid Angiopathy Causing Lobar Hemorrhage Decades After Childhood Neurosurgery.

BACKGROUND: Recent reports raise the possibility of cerebral amyloid angiopathy (CAA) leading to intracerebral hemorrhage in young adults following childhood neurosurgery, suggesting transmission of amyloid-ß (Aß) through neurosurgical procedures including dura mater grafting. Parenchymal Aß deposition, and to a lesser extent tau aggregation, similar to that seen in Alzheimer disease, have also been described. METHODS: We conducted a database review of 634 consecutive intracerebral hemorrhage patients aged <65 years at a tertiary stroke center over 20 years to identify such patients. RESULTS: We identified 3 patients aged in their thirties who presented with spontaneous lobar intracerebral hemorrhage, with imaging or neuropathology consistent with CAA, and a history of childhood neurosurgery. Two of these patients had undergone a dural repair using cadaveric dura mater (Lyodura). In addition to CAA, both patients had neuropathologically confirmed parenchymal Aß and tau deposits, characteristic of Alzheimer disease. CONCLUSIONS: Our findings support the concept of neurosurgical Aß transmission but suggest that such cases are rare in standard clinical practice.

Familial intracranial ependymoma mimicking an extra-lesion: A case report and review of the literature.

Familial occurrence of intracranial ependymoma, in the absence of neurofibromatosis type 2 (NF2), is very rare with only a few cases reported in the literature. We report a 62-year-old man, who presented with a posterior fossa ependymoma with the majority of the lesion in the cerebellopontine angle, mimicking an extra-axial tumour. His two brothers also had 4th ventricular ependymomas requiring surgical resection. Such cases add weight to the suggestion of a genetically predisposing mutation in familial cases of intracranial ependymomas. Further genetic testing may help to elucidate the location of the genetic abnormality in patients with non-NF2 familial intracranial ependymomas and promote a better understanding of this rare pathological entity.

Intraoperatively predicting postoperative sagittal balance using intraoperative X-rays.

This study aimed to assess the correlation of sagittal balance parameters measured intraoperatively, against the gold standard post-operative standing full spine X-ray. A secondary aim was to create a predictive algorithm, that could be used intraoperatively to predict the post-operative balance. 49 patients, who underwent thoracolumbar spinal fusion over a 12-month period were included in this study. Standing full-spine X-rays were obtained both pre and post-surgical fixation. Parallel intraoperative X-rays were taken with the c-arm centred on femoral heads, operative level, S1 and L1. The sagittal parameters pelvic incidence (PI), lumbar lordosis (LL), spino-pelvic mismatch (PI-LL), and sagittal vertical axis were then measured and the correlations statistically analysed. For prone positioned patients the mean LL was 59.9°â€¯±â€¯10.6° intraoperatively (post-fixation) and post-operatively 55.4°â€¯±â€¯10.9° with a mean difference of -4.5°â€¯±â€¯6.1° (p-value < 0.001). For laterally positioned patients the mean LL was 50.9°â€¯±â€¯8.6° intraoperatively and 53.1°â€¯±â€¯10.1° postoperatively for a mean difference of -2.3°â€¯±â€¯6.5° (p-value = 0.117). The linear regression analysis resulted in a predictive algorithm that can be utilised intraoperatively to predict the post-operative standing pelvic mismatch for prone positioned patients. In conclusion, measuring spino-pelvic parameters of sagittal balance intraoperatively can be used to estimate postoperative standing full spine x-ray result. Specifically, in the prone position, the surgeon should aim for intraoperative lordosis that is 4.5° more than the desired post-operative lordosis. The predictive formula provides a direct method to quickly calculate the post-operative pelvic mismatch intraoperatively.

Endovascular repair of an ductus arteriosus aneurysm causing Ortner syndrome.

A ductus arteriosus aneurysm (DAA) is a rare but potentially fatal condition in adults. In the past, open surgery was the only available option for treatment. Nowadays, endovascular repair has emerged as a safe and less invasive treatment option for aortic aneurysms. However, there is little experience with DAA and its anatomic location can complicate endovascular repair. Here, we describe the case of a 69-year-old patient who presented with Ortner syndrome caused by DAA, which was successfully treated using a solely endovascular approach and a standard stent graft.

Deep vein thrombosis and pulmonary embolus in patients with traumatic brain injury: a prospective observational study.

BACKGROUND: Intensive care patients with traumatic brain injury (TBI) are at high risk of developing deep vein thrombosis (DVT). A high rate of DVT was reported before routine thromboprophylaxis, but the current DVT rate in TBI patients receiving best-practice mechanical and pharmacological prophylaxis is unknown. OBJECTIVES: To determine the prevalence of DVT among TBI patients. DESIGN, PARTICIPANTS AND SETTING: A prospective observational pilot study of adult patients admitted to the intensive care unit of a level 1 trauma centre within 72 hours of sustaining a TBI (Glasgow Coma Scale score _14). MAIN OUTCOME MEASURES: Rate of DVT determined using twice-weekly compression ultrasound; rate of pulmonary embolism (PE) and length of stay. RESULTS: 36 patients (28 men; mean age, 40.3 years) were included. Six had moderate and 21 had severe TBI. Two patients (6%) developed a DVT and two patients (6%) developed a PE. The proximal leg DVT rate was 3%, but the overall venous thromboembolism rate was 11% (4 patients). CONCLUSIONS: Mechanical and pharmacological prophylaxis appeared to be effective. The incidence of clinically identified PE is of concern and suggests that thromboembolic sources other than large leg veins may not be being adequately controlled by modern thromboprophylaxis regimens.