Peptidergic innervation of human cerebral blood vessels and saccular aneurysms

Unruptured aneurysmal clipping complicated by delayed and refractory vasospasm: case report

Background

Delayed symptomatic vasospasm is a rare complication following clipping of an unruptured intracranial saccular aneurysm. There have been ten reported cases of delayed symptomatic vasospasm and only two of these occurred after 2 weeks from initial intervention. Our case is the first to document the refractory nature of such vasospasm despite aggressive first line therapy.

Case presentation

Here, we present a 67-year-old female who had surgical clipping of a 10x7mm right middle cerebral artery (MCA) bifurcation aneurysm. Her surgery and initial postoperative course were uncomplicated, but she presented with acute left hemiparesis, dysarthria, headache and vomiting on post-op day 29 secondary to vasospasm of M2. She was initially stabilized with intra-arterial verapamil then managed with volume expansion, permissive hypertension, and nimodipine. She developed recurrent vasospasm of M2 the following day and was again treated with intra-arterial verapamil. Magnetic resonance imaging (MRI) brain showed an infarction involving the right basal ganglia, frontal lobe, and parietal lobe and her hospital course was complicated by super-refractory status epilepticus. At her follow up appointment she displayed continued left lower extremity weakness, left visual field defect, and left-sided neglect.

Conclusions

Overall, cerebral vasospasms associated with unruptured aneurysms remain rare complications and are not often monitored for after initial recovery. Reviewing the documented cases highlights the unpredictability of when these events occur with our current knowledge. Current hypotheses for the mechanisms responsible for delayed and refractory vasospasms include: blood-derived breakdown products, mechanically induced vasospastic responses, and delayed reactions from the trigemino-cerebrovascular system (TCVS). The uncertainly of these events warrants further research and supports a strong argument for monitoring patients with initial surgical clipping up to a month out from their initial procedure.

Delayed Ischemic Neurological Deficit after Uneventful Elective Clipping of Unruptured Intracranial Aneurysms

Cerebral vasospasm and subsequent delayed ischemic neurological deficit is a typical sequela of acute subarachnoid hemorrhage after aneurysm rupture. The occurrence of vasospasms after uncomplicated surgery of an unruptured aneurysm without history of suspected rupture is extremely rare. The pathogenesis and severity of cerebral vasospasms is typically correlated with the amount of blood breakdown products extravasated during subarachnoid hemorrhage. In rare cases, where vasospasms occur after unruptured aneurysm surgery, the pathogenesis is most likely multifactorial and unclear. We present two cases of vasospasms following uncomplicated clipping of middle cerebral artery (MCA) aneurysms and a review of literature. Early diagnosis and therapy of this rare complication are necessary to achieve optimal clinical outcomes.

Recurrent Cerebral Vasospasm and Delayed Cerebral Ischemia Weeks Subsequent to Elective Clipping of an Unruptured Middle Cerebral Artery Aneurysm

BACKGROUND

Cerebral vasospasm and delayed ischemic neurologic deficits are well-known clinical aftereffects of subarachnoid hemorrhage due to rupture of an intracranial aneurysm. However, vasospasm with consequential ischemia after clipping of an unruptured aneurysm is an exceedingly rare sequela encountered in the reported neurosurgical literature.

CASE DESCRIPTION

A 53-year-old woman had presented for elective craniotomy with microsurgical clipping of an unruptured left middle cerebral artery bifurcation saccular aneurysm, which was successfully treated without complications. Despite an initially benign clinical course, she experienced diffuse vasospasm with profound ischemic neurologic deficits on postoperative day 13 with a left middle cerebral artery distribution ischemic infarct. Moreover, she developed recurrent delayed spasm of the right posterior cerebral artery on postoperative day 26 and, consequentially, a left homonymous hemianopsia despite treatment with intra-arterial verapamil infusion.

CONCLUSIONS

To the best of our knowledge, we have reported the first case of recurrent cerebral vasospasm and delayed ischemia neurologic deficits weeks subsequent to clipping of an unruptured aneurysm. The findings from the present case highlight the importance of considering delayed vasospasm as a cause of acute onset neurologic symptoms for patients who have recently undergone elective aneurysm surgery. We also reviewed the current data regarding the epidemiology, surgical factors, and proposed pathophysiologic mechanisms related to vasospasm after elective cases.

Contralateral Vasospasm in an Uncomplicated Elective Anterior Communicating Artery Aneurysm Clipping

BACKGROUND

Cerebral vasospasm following clipping of an unruptured aneurysm is a rare phenomenon. When it does occur, cerebral vasospasm usually occurs on the side ipsilateral to the surgical intervention.

CASE DESCRIPTION

A 68-year-old man underwent right-sided pterional craniotomy for clipping of an unruptured anterior communicating artery aneurysm and experienced contralateral vasospasm 5 days later.

CONCLUSIONS

We further discuss the pathophysiology underlying vasospasm after uncomplicated craniotomy and nonhemorrhagic aneurysm clipping.

A Case of Unexpected Symptomatic Vasospasm after Clipping Surgery for an Unruptured Intracranial Aneurysm

Delayed symptomatic vasospasm after clipping surgery for unruptured aneurysm is rarely reported. We report a case of a 62-year-old woman who presented with symptomatic vasospasm 11 days after clipping surgery for an unruptured aneurysm. We could not predict the existence of vasospasm until ischemic symptoms developed. We retrospectively found mild vasospasm in the computed tomography angiogram taken 8 days after the operation. The patient complained of a prolonged unexpected headache 1 week after the operation. We should recognize prolonged unexpected headache as a warning sign of vasospasm.

Migraine: where and how does the pain originate?

Migraine is a complex neurological disease with a genetic background. Headache is the most prominent and clinically important symptom of migraine but its origin is still enigmatic. Numerous clinical, histochemical, electrophysiological, molecular and genetical approaches form a puzzle of findings that slowly takes shape. The generation of primary headaches like migraine pain seems to be the consequence of multiple pathophysiological changes in meningeal tissues, the trigeminal ganglion, trigeminal brainstem nuclei and descending inhibitory systems, based on specific characteristics of the trigeminovascular system. This contribution reviews the current discussion of where and how the migraine pain may originate and outlines the experimental work to answer these questions.

Cerebral vasospasm in patients with unruptured intracranial aneurysms

Intracranial arterial vasospasm is a typical sequela of subarachnoid haemorrhage. The association between symptomatic vasospasm and unruptured aneurysms has been sporadically presented in the literature. The pathogenesis of this unusual entity is unclear. The published cases were collected in this review and analysed with regard to timing, clinical presentation and possible relationship with surgical factors. We also added an illustrative case which was recently observed in our department.

Raeder's syndrome after embolization of a giant intracavernous carotid artery aneurysm: pathophysiological considerations

We present the case of a 47 years old woman submitted to an endovascular trapping of a left cavernous internal carotid artery aneurysm, in which the distal balloon was inflated, as usually done, within the cavernous segment of the internal carotid artery, different from the proximal one which was inflated inside the carotid canal due to technical problems. Consequently, a clinical picture of Raeder's paratrigeminal neuralgia took place. This is the first case report in the literature with theses characteristics. A review of the anatomic pathways and further considerations about the possible pathophysiological mechanisms involved are presented.

Arterial sympathetic innervation and cerebrovascular diseases in original rat models

The role of the arterial sympathetic innervation in cerebrovascular pathology was investigated in new experimental models using Brown Norway (BN) and Long-Evans (LE) rats. The BN rat is susceptible to intracerebral hemorrhage (ICH) within the cerebral cortex when rendered hypertensive whereas the LE rat is prone to cerebral aneurysms (CAs) in arteries of the circle of Willis with hypertension and carotid ligation. Noradrenaline (NA) content, determined by high performance liquid chromatography (HPLC), was lower both in the caudal and cerebral arteries in the BN than in the LE rat. Denervation of cerebral arteries by superior cervical ganglionectomy did not increase ICH lesion incidence in BN hypertensive rats. A possible link between the level of caudal artery NA content and the occurrence of ICH lesions and CAs was studied in rats from two distinct BNXLE crosses: back-cross (BC) rats (F1XBN) and F2 rats (F1XF1) which respectively display, with hypertension and carotid ligation, a high incidence of either ICH lesions or CAs. In BC rats, the level of caudal artery NA content was not related to ICH lesion occurrence. However, in F2 rats a low caudal artery NA content was associated with a high incidence of ruptured CAs. Thus, a low arterial sympathetic innervation may participate in mechanisms leading to rupture of CAs.

Innervation of cerebral blood vessels: morphology, plasticity, age-related, and Alzheimer's disease-related neurodegeneration

The light microscopical and ultrastructural morphology of the innervation of the major cerebral arteries and pial vessels is described, including the origins of the different groups of nerve fibres and their characteristic neurotransmitter phenotype. Species and region specific variations are described and novel data regarding the parasympathetic innervation of cerebral vessels are presented. The dynamic nature, or plasticity, of cerebrovascular innervation is emphasized in describing changes affecting particular subpopulations of neurons during normal ageing and in Alzheimer's disease. The molecular controls on plasticity are discussed with particular reference to target-associated factors such as the neurotrophins and their neuronal receptors, as well as extracellular matrix related factors such as laminin. Hypotheses are presented regarding the principal extrinsic and intrinsic influences on plasticity of the cerebrovascular innervation.