26 Underlying Intracranial Stenosis
26.1 Case Description
26.1.1 Clinical Presentation
A 59-year-old male with hypertension and smoking history presented with severe dysarthria, right-sided weakness, and altered level of consciousness (LOC). He was last known well at 16:00 hours. He called his partner at 03:40 hours, but only breathing noises were audible and the patient was not able to talk. His family rushed to his home and found him on the couch, unable to speak, and unable to move his right arm. He was moving his lower limbs, left more so than right. Emergency medical service (EMS) was called and he was brought to the stroke center as a code stroke at 04:38 hours.
National Institutes of Health Stroke Scale (NIHSS) score was 14 for severe dysarthria, right-arm weakness, bilateral lower limb weakness, and ataxia. He was also found to have altered LOC.
26.1.2 Imaging Workup and Investigations
Noncontrast computed tomography (NCCT) done shortly after presentation to the emergency department (about 80 minutes after discovery of symptom onset) revealed hyperdense basilar artery (Fig. 26.1a).
CT angiography (CTA) revealed long-segment occlusion of the basilar artery (Fig. 26.1b).
CT perfusion (CTP) showed increased mean transit time (MTT) of the pons and the cerebellum with reduced cerebral blood volume (CBV) and cerebral blood flow (CBF). It was uncertain if it was truly infarcted tissue or an artifact due to photon starvation and streak artifact (Fig. 26.1c).
Basilar artery long-segment occlusion with significant streak artifact over the pons, limiting the assessment of early infarction. Corresponding abnormal tissue perfusion tissue of the posterior fossa.
Due to uncertainty of time of onset, tissue plasminogen activator (tPA) was not given.
Patient was intubated in the emergency department prior to transfer to the angiography suite.
26.1.5 Endovascular Treatment
8-Fr short vascular access sheath.
6-Fr Neuron MAX 088 access catheter (Penumbra, Inc.).
HH1 Impress hydrophilic catheter (Merit, Inc.).
5 MAX ACE 68 aspiration catheter (Penumbra, Inc.).
3 MAX aspiration catheter (Penumbra, Inc.).
Transend EX soft tip microguidewire.
Trevo XP ProVue microcatheter.
Synchro 14 microwire.
Trevo XP ProVue 4 × 20 mm stent retriever.
Procedure performed under general anesthesia.
As tPA was not provided, heparin was given to keep the activated clotting time (ACT) between 250 and 300 throughout the course of the procedure.
Right common femoral artery (CFA) puncture with placement of an 8-Fr short vascular access sheath into the CFA.
The 6-Fr Neuron MAX 088 access catheter (Penumbra, Inc.) and the HH1 Impress hydrophilic catheter were prepared and connected to a continuous flush. The system was then used to catheterize the left vertebral artery using roadmap technique with the aid of the Terumo guidewire. The Neuron MAX was advanced to the C2 level, and the HH1 and guidewire were removed.
Diagnostic hand injections in both anteroposterior (AP) and lateral showed long segment occlusion of the basilar artery trunk (Fig. 26.2a).
The 5 MAX ACE 68 aspiration catheter and the 3 MAX aspiration catheter were prepared and connected to continuous flush. Under fluoroscopic guidance with roadmaps, both catheters were navigated coaxially through the Neuron MAX, with the aid of a Transend EX soft tip microguidewire, until the proximal clot margin.
The 3 MAX and the Transend wire were removed.
The 5 MAX ACE 68 aspiration catheter was connected to the penumbra aspiration pump with the connecting tubing, and the pump was primed. When optimal negative pressure was achieved, the connecting tubing valve was opened.
Some blood was seen sucked back into the catheter followed by almost immediate flow arrest. After 90 seconds the 5 MAX was pulled gradually; however, due to the acute angle of the V4 it was difficult to keep the clot engaged.
Hand injection after the 5 MAX removal showed minimal recanalization.
The Trevo XP ProVue microcatheter was prepped and connected to a continuous flush and was then navigated with the aid of a Synchro microwire through the 5 MAX distal to the clot.
Hand injection revealed a micro arteriovenous malformation (AVM) and the intravascular location of the catheter (Fig. 26.2b).
A 4 × 20 mm Trevo stent retriever was deployed along the length of the basilar trunk and first flow was achieved (Fig. 26.2c, d).
Microinjection confirmed the location of the Trevo micro catheter with no perforation.
The 5 MAX was advanced to the proximal aspect of the clot to wedge it and connect it to the Penumbra aspiration pump.
Both the Trevo stent retriever and the 5 MAX were pulled as a unit under aspiration. Clot fragments were retrieved.
Hand injections through the Neuron Max showed the basilar almost completely recanalized with focal midbasilar narrowing. There was less opacification of the right posterior cerebral artery (PCA) with poor visualization of the distal branches (TICI 2b; Fig. 26.2e, f).
2 mg of intra-arterial (IA) tPA was given through the Neuron Max.
After confirmation of proper puncture site, the sheath was removed and an 8-Fr Angio-seal device used for hemostasis.
26.1.6 Postprocedure Care
The patient was transferred to the intensive care unit (ICU). The systolic blood pressure was kept < 180 mm Hg. Dual antiplatelets were started the day after thrombectomy. Atorvastatin 80 mg PO/NG was started daily.
The patient remained intubated and did not improve clinically. He was comatose with ocular bobbing and absence of horizontal gaze movements. There were minimal corneal reflexes, with pupils 2 mm and sluggishly reactive. Decerebrating posturing was observed after tactile stimuli.
Repeat CTA showed reocclusion of the basilar artery (Fig. 26.3), and magnetic resonance imaging (MRI) showed massive posterior circulation infarctions involving the pons, cerebellum and the left occipital lobe (Fig. 26.4). The patient developed “locked in” syndrome. He was kept on mechanical ventilation in the cardiac care unit (CCU), and ultimately the family asked to withdraw life support. He died peacefully.
26.2 Companion Case
26.2.1 Clinical Presentation
A 40-year-old woman was transferred as a code stroke, presenting with right hemiparesis inability to speak, and a NIHSS score of 16. Computed tomography (CT)/CTA/CTP of head demonstrated a mid to distal basilar artery occlusion. She was not a tPA candidate, given the uncertain onset of symptoms, and was sent for endovascular therapy.
26.2.2 Imaging Workup and Investigations
NCCT performed shortly after presentation to the emergency department revealed hyper dense basilar artery and hypodensities of the bilateral thalami and the right occipital lobe. (Fig. 26.5)
CTA revealed mid to distal basilar artery occlusion (Fig. 26.5).
Scattered foci of diffusion restriction in the posterior circulation, involving both thalami, midbrain, pons, and right occipital lobe (Fig. 26.6)
Given the patient’s young age, the stroke team agreed to take the patient to the angiography suite for mechanical thrombectomy, and informed consent was obtained from the family.
26.2.4 Endovascular Treatment
5-Fr and 6-Fr short vascular access sheaths.
5-Fr Bernstein diagnostic catheter.
6-Fr Envoy DA catheter.
Trevo 18 microcatheter.
TrevoXP ProVue 4 × 20 mm stent retriever.
Transend EX soft tip microguidewire.
Solitaire 4 mm × 30 mm stent retriever.
The procedure was performed under general anesthesia with the patient intubated.
Bilateral CFA punctures were performed with placement of 6-Fr short vascular access sheath into the right CFA and 5-Fr sheath in the left.
The 5-Fr Bernstein diagnostic catheter was navigated into the right common carotid artery (CCA) and internal carotid artery (ICA) to assess the posterior communicating artery and the PCA.
The 6-Fr Envoy DA catheter was navigated into the left vertebral artery. AP and lateral runs showed distal basilar occlusion with midbasilar artery diameter change, large left extracranial origin of posterior inferior cerebellar artery (PICA), duplicated left anterior inferior cerebellar artery (AICA), right AICA/PICA, and a small accessory right AICA.
Double-catheter simultaneous runs showed good roadmap for mechanical thrombectomy (Fig. 26.7).
Trevo 18 microcatheter was navigated into the left P1 with the aid of a Transend EX soft tip microguidewire. Superselective run confirmed intravascular positioning.
TrevoXP ProVue 4 × 20 mm stent retriever was deployed and incubated for 5 minutes before retrieval. Repeat left vertebral artery run showed partial recanalization to left P1.
Similar steps were performed for the right P1.
Repeat left vertebral artery run showed partial recanalization of bilateral P1s and superior cerebellar arteries (SCAs). The flow was not robust, with severe stenosis at distal basilar trunk, so a decision was taken to deploy Solitaire stent across the severe stenosis.
Microcatheter was advanced to the left distal PCA.
Solitaire 4 × 30 mm stent was deployed across basilar stenosis and detached.
Working projection runs showed improved flow from distal basilar trunk to PCAs and SCAs. A small filling defect just proximal to right SCA origin was visualized.
ReoPro loading dose was given and infusion continued while in ICU.
Final AP, lateral runs from left vertebral and right internal carotid showed no other complications.
Catheters were removed, and a 6-Fr Angio-Seal was used for hemostasis.