Adult hemiconvulsive hemiatrophy syndrome: a novel clinicoradiologic disorder in adults.

The association of focal motor seizures with cerebral hemiatrophy is a recognised rare paediatric syndrome known as 'hemiconvulsion, hemiatrophy and epilepsy' (HHE). To date, HHE has not been reported in adults. We present four adult patients with striking similarities to HHE, following alcohol withdrawal in chronic alcoholics. We document the imaging findings in the acute and subacute phases, discuss the underlying mechanisms and present a hypothesis regarding the pathophysiology.

The Great Contrast Shortage of 2022-Lessons learnt in Australia.

INTRODUCTION: Computed tomography (CT) imaging is one of the most commonly used diagnostic tools. Iodine-based contrast media (IBCM) are frequently administered intravenously to improve soft tissue contrast in a wide range of CT scans. Supply chain disruptions triggered by the SARS-CoV-19 pandemic led to a global shortage of IBCM in mid-2022. The purpose of this study was to explore the impact of this shortage on the delivery of healthcare in Western Australia. METHODS: We performed a single-centre retrospective analysis of the provision of CT studies, comparing historical patterns to the shortage period. We focussed our attention on the total number of CT scans (noncontrast CT [NCCT] and contrast-enhanced CT [CECT]) and also specifically CT pulmonary angiogram (CTPA) and CT neck angiogram with or without inclusion of circle of Willis (CTNA) examinations. We also examined whether a decrease was compensated by increasing frequency of alternate examinations such as ventilation/perfusion (V/Q) scans, carotid Doppler ultrasound studies and Magnetic Resonance Angiograms (MRAs). RESULTS: Since 2012, there has been an approximate linear increase in the frequency of CT examinations. During the period of contrast shortage, there was an abrupt drop-off by approximately 50% in the CECT, CTPA and CTNA groups compared with the preceding 6 weeks (49%, 55% and 44%, respectively, with P < 0.001 in all cases). During the contrast shortage, the frequency of V/Q scans increased fivefold (from 13 to 65; P < 0.001). However, the provision of carotid Doppler ultrasound studies and MRAs remained approximately stable in frequency across recent time intervals. CONCLUSION: Our findings demonstrate that the IBCM shortage crisis had a very significant impact on the delivery of healthcare. While V/Q scans could (partially) substitute for CTPA studies in suspected pulmonary emboli, there appeared to be no valid alternative for CTNA studies in stroke calls. The unexpected and critical shortage of IBCM forced healthcare professionals to conserve resources, prioritise indications, triage patients based on risk, explore alternate imaging strategies and prepare for similar events recurring in the future.

Transradial versus transfemoral access for anterior circulation mechanical thrombectomy: analysis of 375 consecutive cases.

OBJECTIVE: To compare transradial artery access (TRA) to the gold standard of transfemoral artery access (TFA) in mechanical thrombectomy (MT) for stroke caused by anterior circulation large vessel occlusion. METHODS: The clinical outcomes, procedural speed, angiographic efficacy and safety of both techniques were analysed in 375 consecutive cases over an 18-month period in a high volume statewide neurointerventional service. RESULTS: There was no significant difference in patient characteristics, stroke parameters, imaging techniques or intracranial techniques. The median time elapsed between CT scanning and reperfusion was 96.5 min (IQR 68-123) in the TFA group and 95 min (IQR 68-123) in the TRA group (p=0.456). Of 336 patients who were independent at presentation 58% (124/214) of the TFA group and 67% (82/122) of the TRA group had a modified Rankin score of 0-2 at 90-day follow-up (p=0.093). Cross-over from radial to femoral was 4.6% (4/130) compared with 1.6% cross-over from femoral to radial (4/245), but did not meet the predetermined level of statistical significance (OR 2.92, 95% CI 0.81 to 10.52), p=0.088) and did not impact median procedural speed. Adequate angiographic reperfusion, first pass reperfusion, embolisation to new territory and symptomatic intracranial haemorrhage were similar in both groups. There was a significant difference in major access site complications requiring an additional procedure. None of the TRA cases had a major access site complication but 6.5% (16/245) of the TFA cases did (p=0.003). CONCLUSION: This study suggests that using TRA for anterior circulation MT is fast, efficacious, safe and not inferior to the gold standard of TFA.

Perianeurysmal vasogenic oedema (PAVO) following aneurysm embolisation: a unique case of asymptomatic long-term progression and review of the literature.

Perianeurysmal vasogenic oedema is a recognised although rare phenomenon following endovascular treatment of certain intracranial aneurysms. We present a unique case of asymptomatic perianeurysmal vasogenic oedema following bare platinum coil embolisation of an incidentally discovered right middle cerebral artery aneurysm that slowly increased over a period of 6 years before stabilising and regressing. During this time, the coiled aneurysm per se remained completely stable on serial magnetic resonance angiography.

A rare suspected case of chronic nodular granulomatous herpes simplex encephalitis in an adult.

Herpes simplex encephalitis is the most common sporadic viral encephalitis in the western world, HSV-1 (herpes simplex virus) being the mostly commonly implicated serotype. The disease is usually monophasic, although patients may relapse weeks, months or years after initial infection. This chronic granulomatous inflammatory process is almost exclusively described in children and rarely forms discrete enhancing parenchymal nodules. We present the clinical and radiological features of an unusual case of chronic nodular granulomatous herpes encephalitis with enhancing "mass-like" nodules in an adult. To the author's knowledge, this is the first reported case of macroscopic "mass-like" nodular granuloma formation in an adult.

Embolization for the treatment of intractable epistaxis: 12 month outcomes in a two centre case series.

OBJECTIVE: Embolization is a treatment option for intractable epistaxis; however, concerns regarding tissue necrosis, stroke and blindness persist in the literature. METHODS: A retrospective review of patients from September 2010 to January 2016 treated with embolization for epistaxis was performed. No patient was excluded. Follow-up was 12 months and no patient was lost. RESULTS: 62 embolizations on 59 patients occurred. 21 cases were taking anticoagulants, P2Y12 inhibiting agents or had a systemic coagulopathy. Embolized territories typically involved bilateral distal internal maxillary arteries with unilateral or bilateral facial arteries with polyvinyl alcohol particles. 60 cases had procedural general anaesthesia. There were no major complications. Six died of unrelated causes. Of the surviving 53 patients, excluding the 3 patients with hereditary haemorrhagic telangiectasia, 5 had recurrent epistaxis post-embolization. Four were taking P2Y12 inhibiting and/or anticoagulants, none of which required surgery, prolonged packing or repeat embolization. This group had a propensity to recur compared with cases taking aspirin only or no antiplatelet/anticoagulant (77.8 vs 97.1%, p = 0.04). The fifth underwent repeat embolization after previously only having ipsilateral distal internal maxillary and facial arteries treated. CONCLUSION: Embolization for epistaxis is safe and effective. Of those who had recurrent epistaxis post embolization, most were taking P2Y12 inhibition and/or anticoagulation. We prefer bilateral distal internal maxillary artery and unilateral facial artery embolization under general anaesthesia for optimal safety and efficacy. Advances in knowledge: Embolization with this technique seems to facilitate superior outcomes without complications despite the large proportion of patients taking anticoagulating or P2Y12 inhibiting agents.

Outcomes of Endovascular Thrombectomy with and without Thrombolysis for Acute Large Artery Ischaemic Stroke at a Tertiary Stroke Centre.

BACKGROUND AND PURPOSE: Endovascular thrombectomy (EVT) improves the functional outcome when added to best medical therapy, including alteplase, in patients with acute ischaemic stroke secondary to large vessel occlusion (LVO) in the anterior circulation. However, the evidence for EVT in alteplase-ineligible patients is less compelling. It is also uncertain whether alteplase is necessary in patients with successful recanalization by EVT, as the treatment effect of EVT may be so powerful that bridging alteplase may not add to efficacy and may compromise safety by increasing bleeding risks. We aimed to survey the proportion of patients suitable for EVT who are alteplase-ineligible and to compare the safety and effectiveness of standard care of acute large artery ischaemic stroke by EVT plus thrombolysis with that of EVT alone in a tertiary hospital clinical stroke service. METHODS: We performed a retrospective analysis of acute ischaemic stroke patients treated with EVT at our centre between October 2013 and April 2016, based on a registry with prospective and consecutive patient collection. Individual patient records were retrieved for review. Significant early neurological improvement was defined as a NIHSS score of 0-1, or a decrease from baseline of ≤8, at 24 h after stroke onset. RESULTS: Fifty patients with acute ischaemic stroke secondary to LVO in the anterior circulation received EVT in this period, of whom 21 (42%) received concurrent alteplase and 29 (58%) EVT alone. The 2 groups had similar baseline characteristics and similar outcomes. Significant neurological improvement at 24 h occurred in 47.6% of the patients with EVT and bridging alteplase and in 51.7% of the patients with EVT alone (p = 0.774). Mortality during acute hospitalization was 20% for the bridging alteplase group versus 7.1% for EVT alone (p = 0.184). Intracranial haemorrhage rates were 14.3% for bridging alteplase versus 20.7% for EVT alone (p = 0.716). Local complications, groin haematoma (23.8 vs. 10.3%) and groin pseudoaneurysms (4.8 vs. 0%) (p = 0.170), were not significantly different. CONCLUSION: Our study highlights the relatively large proportion of patients suitable for EVT who have a contraindication to alteplase and raises the hypothesis that adding alteplase to successful EVT may not be necessary to optimize functional outcome. The results are consistent with observational data from other endovascular centres and support a randomised controlled trial of EVT versus EVT with bridging alteplase.

Mechanical thrombectomy for anterior circulation stroke: 5-year experience in a statewide service with differences in pretreatment time metrics across two hospitals sites.

OBJECTIVE: To audit our institutional mechanical thrombectomy (MT) outcomes for acute anterior circulation stroke and examine the influence of workflow time metrics on patient outcomes. METHODS: A database of 100 MT cases was maintained throughout May 2010-February 2015 as part of a statewide service provided across two tertiary hospitals (H1 and H2). Patient demographics, stroke and procedural details, blinded angiographic outcomes, and 90-day modified Rankin Scale (mRS) scores were recorded. The following time points in stroke treatment were recorded: stroke onset, hospital presentation, CT imaging, arteriotomy, and recanalization. Statistical analysis of outcomes, predictors of outcome, and differences between the hospitals was carried out. RESULTS: Thrombolysis in Cerebral Infarction (TICI) 2b/3 reperfusion was 79%. Forty-nine per cent of patients had good clinical outcomes (mRS 0-2). In a subgroup analysis of 76 patients with premorbid mRS 0-1 and first CT performed ≤4.5 h after stroke onset, 60% had good clinical outcomes. Patient and disease characteristics were matched between the two hospitals. H1 had shorter times between hospital presentation and CT (32 vs 55 min, p=0.01), CT and arteriotomy (33 vs 69 min, p=0.00), and stroke onset and recanalization (198 vs 260 min, p=0.00). These time metrics independently predicted good clinical outcome. Median days spent at home in the first 90 days was greater at H1 (61 vs 8, p=0.04) than at H2. A greater proportion of patients treated at H1 were independent (mRS 0-2) at 90 days (54% vs 42%); however, this was not statistically significant (p=0.22). CONCLUSIONS: Outcomes similar to randomized controlled trials are attainable in 'real-world' settings. Workflow time metrics were independent predictors of clinical outcome, and differed between the two hospitals owing to site-specific organizational differences.

CT perfusion in acute stroke calls: A pictorial review and differential diagnoses.

CT perfusion is increasingly utilised in hyperacute stroke to facilitate diagnosis and patient selection for reperfusion therapies. This review article demonstrates eight examples of how CT perfusion can be used to diagnose stroke mimics and small volume infarcts, which can be easily missed on non-contrast CT, and to suggest the presence of an ischaemic penumbra. Radiologists involved in stroke management must understand the importance of rapid imaging acquisition and be confident in the prospective interpretation of this powerful diagnostic tool as we move into a new era of hyperacute stroke care.

De novo cavernoma developing from an asymptomatic thalamic microhemorrhage.

Cavernomas are low-flow vascular lesions affecting approximately 0.5% of the population. Historically these have been considered congenital lesions, but numerous reports have demonstrated de novo formation. The phenomenon is well documented in patients with the familial disease form and after cranial radiotherapy, but outside of these circumstances there is scant evidence as to the potential etiology. The authors present a 5 year MRI series of a 56-year-old woman with no known risk factors demonstrating cavernoma formation and growth from previously normal brain. The patient was consistently asymptomatic during follow-up. Given the history and imaging findings, we propose that cavernomas can arise directly from angiogenic proliferation secondary to microhemorrhage from unrelated causes.

Endovascular treatment of complex aneurysms at the vertebrobasilar junction with flow-diverting stents: initial experience.

BACKGROUND: Large or giant complex vertebrobasilar junction aneurysms have a dismal natural history and are often challenging to treat with standard endovascular or neurosurgical techniques. OBJECTIVE: To report initial experience with endovascular treatment of these aneurysms using flow-diverting stents (FDS). METHODS: Ten patients with FDS treatment of complex vertebrobasilar junction aneurysms were collected from 4 large cerebrovascular centers. Clinical/angiographic presentation and outcome were retrospectively analyzed. RESULTS: Of 10 aneurysms, 7 presented with brainstem compression, 2 with ischemia, and 1 with subarachnoid hemorrhage, and 3 were recurrent after stent-assisted treatments. Eight were giant. Morphology was fusiform in 5, fusiform dissecting in 1, and multilobulated saccular in 4. Six were partially thrombosed. In addition to FDS (mean number of devices, 3.9; range, 1-9), contralateral vertebral artery sacrifice and adjunctive coiling were performed in 9 and 5 of the 10 patients, respectively. At follow-up, 5 of 10 were completely occluded, 4 showed minimal residual filling, and 1 was retreated with an additional FDS. Postinterventionally, worsening mass effect and ischemic complications were seen in 2 and 4 of 10, respectively. Clinical outcome was good in 6 (modified Rankin Scale score, 0-2). Four fatalities were related to sequelae of subarachnoid hemorrhage, late FDS thrombosis, progressive mass effect, and delayed intracranial hemorrhage. CONCLUSION: FDS may be used to treat complex vertebrobasilar junction aneurysms with overall good angiographic outcome. A combined reconstructive/deconstructive approach appears useful to avoid endoleaks. FDS strategies, like other endovascular and neurosurgical approaches to these lesions, are associated with significant risk and therefore should be reserved for those cases in which alternative approaches either are deemed unsafe or are likely to be ineffective. ABBREVIATIONS: FDS, flow-diverting stentPED, Pipeline Embolization DeviceSAH, subarachnoid hemorrhageVA, vertebral arteryVBJ, vertebrobasilar junction.

Arterial origin subdural hematoma and associated pial pseudoaneurysm following minor head trauma.

The vast majority of primary acute subdural hematomas following trauma are venous in origin. We report a very rare case of a primary acute subdural hematoma following minor head trauma that was arterial in origin and was associated with a pial cortical branch pseudoaneurysm. The patient was managed conservatively, and follow-up imaging demonstrated complete resolution of both lesions.

Vertebrobasilar insufficiency.

Vertebrobasilar insufficiency presents with characteristic symptoms and signs due to impaired perfusion of the cerebellum, the brain stem, and the occipital cortex. This may be due to reduced perfusion usually due to atherosclerosis or thromboembolism. Choice of treatment depends on understanding the different underlying pathophysiologic mechanisms. Antiplatelet therapy; reduction of risk factors such as diabetes, hypertension, hypercholesterolemia, and cigarette smoking; and a healthy lifestyle form the first line of management. Systemic anticoagulation in the short term also has a key role in selected cases. In patients with refractory symptoms on maximal medical therapy and underlying focal stenotic lesions, endovascular revascularization using stents and balloon angioplasty may be indicated. Bypass surgery is another option if there are factors that render endovascular therapy unsuitable.