Use of the Cascade expandable net to treat cerebral vasospasm - initial clinical experience from a single centre with in vitro benchside tests

The Stream Device-A Retrospective Review of 51 Cases

Mechanical thrombectomy is the gold-standard treatment for patients that have suffered large-vessel occlusion (LVO) stroke. Various different stent-retrievers, aspiration catheters, and techniques have been developed to perform this procedure. We present our initial results regarding the Stream device.

MATERIALS AND METHODS

We performed a retrospective review of a prospectively maintained database at our high-volume centre to identify all patients treated with the Stream device between February 2021 and January 2023. We recorded baseline demographics, NIHSS, ASPECT scores, eTICI scores, complications, and 90-day mRS.

RESULTS

We identified 51 patients, 49.0% of whom were male (n = 25), with a median age of 73 (range: 51-89) and a median NIHSS score of 17 (range 4-22), and 68.6% received IV tPA. The median ASPECT score was 10 (range 6-10). Hyperdense clots were seen in 34 cases (66.7%), with a mean clot length of 12 ± 6.2 mm (range 2-26 mm). Clots were located in the anterior circulation in 49 patients. The standard Stream device was used in 78.4% of cases, with Stream 17 being used in 19.6% of cases. The FPE was observed in 25.5% of cases (n = 13), with the mFPE being seen in 31.4% of cases (n = 16). A final eTICI score of ≥2b was achieved in 90.2% of cases (n = 46), and eTICI 2c/3 was seen in 84.3% of cases (n = 43). Furthermore, 24 h CT scans showed that the median ASPECT score was 8 (range 0-10). Good functional outcomes at 90 days (mRS ≤ 2) were achieved in 21.6% of cases (n = 11).

CONCLUSIONS

The Stream device shows acceptable rates of FPE and mFPE compared to existing devices. Further larger studies are required alongside an understanding of the optimal technique for this device's use.

Delayed collapse of flow diverter due to acute severe vasospasm: another concern for flow diversion in ruptured aneurysms

In vivo morphological change of flow diverter stents (FDS) is a known phenomenon and can be seen secondary to various device- and vasculature-related factors such as improper sizing of the device, twisting of the device in tortuous anatomy, insufficient proximal landing zone, and insufficient chronic resistive force of the stent, etc. However, we have encountered a case where severe vasospasm due to aneurysmal subarachnoid hemorrhage led to the collapse of the proximal end of the FDS. Development of vasospasm and consequent possible failure of the device should be taken into consideration when planning flow diversion in ruptured aneurysms.