Regional Mechanical Thrombectomy Imaging Protocol in Patients Presenting with Acute Ischemic Stroke during the COVID-19 Pandemic

BACKGROUND AND PURPOSE

Chest CT is a rapid, useful additional screening tool for coronavirus disease 2019 (COVID-19) in emergent procedures. We describe the feasibility and interim outcome of implementing a modified imaging algorithm for COVID-19 risk stratification across a regional network of primary stroke centers in the work-up of acute ischemic stroke referrals for time-critical mechanical thrombectomy.

MATERIALS AND METHODS

We undertook a retrospective review of 49 patients referred to the regional neuroscience unit for consideration of mechanical thrombectomy between April 14, 2020, and May 21, 2020. During this time, all referring units followed a standard imaging protocol that included a chest CT in addition to a head CT and CT angiogram to identify Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) infective pulmonary changes.

RESULTS

Overall, 2 patients had typical COVID-19 radiologic features and tested positive, while 7 patients had indeterminate imaging findings and tested negative. The others had normal or atypical changes and were not diagnosed with or suspected of having COVID-19. There was an overall sensitivity of 100%, specificity of 74.1%, negative predictive value of 100%, and positive predictive value of 22.2% when using chest CT to diagnose COVID-19 in comparison with the real-time reverse transcriptase-polymerase chain reaction test. The mean additional time and radiation dose incurred for the chest CT were 184 ± 65.5 seconds and 2.47 ± 1.03 mSv. Multiple cardiovascular and pulmonary incidental findings of clinical relevance were identified in our patient population.

CONCLUSIONS

Chest CT provides a pragmatic, rapid additional tool for COVID-19 risk stratification among patients referred for mechanical thrombectomy. Its inclusion in a standardized regional stroke imaging protocol has enabled efficient use of hospital resources with minimal compromise or delay to the overall patient treatment schedule.

Mechanical thrombectomy for acute ischaemic stroke during the COVID-19 pandemic: changes to UK practice and lessons learned

AIM

To describe evolving practices in the provision of mechanical thrombectomy (MT) services across the UK during the COVID-19 pandemic, the responses of and impact on MT teams, and the effects on training.

MATERIALS AND METHODS

The UK Neurointerventional Group (UKNG) and the British Society of Neuroradiologists (BSNR) sent out a national survey on 1 May 2020 to all 28 UK neuroscience centres that have the potential capability to perform MT.

RESULTS

Responses were received from 27/28 MT-capable centres (96%). Three of the 27 centres do not currently provide MT services. There was a 27.7% reduction in MTs performed during April 2020 compared with the first 3 months of the year. All MT patients in 20/24 centres that responded were considered as COVID-19 suspicious/positive unless or until proven otherwise. Twenty-two of the 24 centres reported delays to the patient pathway. Seventeen of the 24 centres reported that the COVID-19 pandemic had reduced training opportunities for specialist registrars (SpR). Fourteen of the 24 centres reported that the pandemic had hampered their development plans for their local or regional MT service.

CONCLUSION

The present survey has highlighted a trend of decreasing cases and delays in the patient pathway during the early stages of the COVID-19 pandemic across UK centres.

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National UK MT service survey during COVID-19 lockdown.

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Decline in MTs.

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Delays to patient journey.

Is there a causal relationship between the hypoxia-ischaemia associated with cardiorespiratory arrest and subdural haematomas? An observational study

The aim of this study was to determine the frequency of subdural haematomas (SDHs) occurring in infants presenting following atraumatic cardiorespiratory collapse. This study was a review of retrospective case notes, brain imaging and post-mortem examinations carried out in the paediatric intensive care unit (PICU) and emergency department (ED) in a tertiary paediatric centre in the UK. The study included infants and children less than 4 years old dying in the ED or admitted to the PICU after atraumatic cardiorespiratory arrest. We identified macroscopic SDHs on brain imaging or post-mortem examination. Of those children who experienced a cardiorespiratory arrest from a non-traumatic cause and met inclusion criteria, 33 presented and died in the ED and 17 were admitted to the PICU. These children had a post-mortem examination, brain imaging or both. None of these infants had a significant SDH. One child had a small clot adherent to the dura found on post-mortem and two had microscopic intradural haemorrhage, but it is unclear in each case whether this was artefact, as each had otherwise normal brains. Subdural haematoma arising in infants or young children in the context of catastrophic cardiorespiratory compromise from a non-traumatic cause was not observed.

Neuroendoscopic third ventriculostomy in dysmorphic brains

Neuroendoscopic third ventriculostomy (NTV) has superseded shunting as the treatment of choice in non-communicating hydrocephalus. Intracranial developmental anomalies have been considered to be relative contraindications for this procedure. We present one patient with a Dandy-Walker malformation and another with septo-optic dysplasia who presented with hydrocephalus. An NTV was performed successfully in both patients using a flexible neuroendoscope and utilising transendoscopic Doppler ultrasound to ensure a safe target area for ventriculostomy.

Acoustic neuromas: a review of 58 patients and correlation of tumour-size to the outcome

Fifty eight patients with acoustic neuromas, who presented over a six year period were reviewed. These patients were sub divided into three groups according to their tumour size. Group A comprised of 21 patients with lesions less than 2 cm in diameter, of which 83% presented in the last two years. Group B comprised of 30 patients with lesions measuring 2-4 cm, of which 43% presented in the last two years. Group C included 7 patients with lesions greater than 4 cm in size, of which 14% presented in the corresponding period. The relative increase in the number of patients in Group A and decrease in Group C over the years is a direct reflection of heightened clinical awareness and increased usage of magnetic resonance imaging for diagnosis. Complete surgical excision was achieved in 20/21 patients in Group A and 4/7 patients in Group C, with an overall complete excision rate of 81%. The overall facial nerve preservation rate was 81% of which 20/21 patients were in Group A, 23/30 in Group B and 4/7 in Group C. The surgical morbidity ranged from 10% in Group A to 28% in Group C. There were no deaths in Group A compared to two each in Group B and Group C. This emphasises the importance of early detection and treatment of acoustic neuromas when they are small.