Prediction of vascular abnormalities on CT angiography in patients with acute headache

Comment on Roman-Filip et al. Non-Aneurysmal Perimesencephalic Subarachnoid Hemorrhage: A Literature Review. Diagnostics 2023, 13, 1195

We would like to congratulate Roman-Filip et al. on their recent review on perimesencephalic hemorrhages [...].

Headache Attributed to Reversible Cerebral Vasoconstriction Syndrome (RCVS)

Reversible cerebral vasoconstriction syndrome (RCVS) is a condition with variable outcomes presenting a new onset thunderclap headache accompanied by focal neurological symptoms or seizures. It can be idiopathic or arise secondarily to a variety of trigger factors. The condition is increasingly recognized in clinical practice, but many facets remain poorly understood. This article aims to clarify the headache characteristics in RCVS, the temporal association of angiographic findings, the potential association of the condition with SARS-CoV-2 infection, and the clinical presentation of RCVS in children and is based on a systematic PRISMA search for published analytical or large descriptive observational studies. Data from 60 studies that fulfilled specific criteria were reviewed. Most people with RCVS exhibit a typical thunderclap, explosive, or pulsatile/throbbing headache, or a similar acute and severe headache that takes longer than 1 min to peak. Atypical presentations or absence of headaches are also reported and may be an underrecognized phenotype. In many cases, headaches may persist after resolution of RCVS. Focal deficits or seizures are attributed to associated complications including transient ischemic attacks, posterior reversible encephalopathy syndrome, ischemic stroke, cerebral edema, and intracranial hemorrhage. The peak of vasoconstriction occurs usually within two weeks after clinical onset, possibly following a pattern of centripetal propagation, and tends to resolve completely within 3 months, well after symptoms have subsided. There are a few reports of RCVS occurring in relation to SARS-CoV-2 infection, but potential underlying pathophysiologic mechanisms and etiological associations have not been confirmed. RCVS occurs in children most often in the context of an underlying disease. Overall, the available data in the literature are scattered, and large-scale prospective studies and international collaborations are needed to further characterize the clinical presentation of RCVS.

Aneurysmal Subarachnoid Hemorrhage: the Last Decade

Aneurysmal subarachnoid hemorrhage (SAH) affects six to nine people per 100,000 per year, has a 35% mortality, and leaves many with lasting disabilities, often related to cognitive dysfunction. Clinical decision rules and more sensitive computed tomography (CT) have made the diagnosis of SAH easier, but physicians must maintain a high index of suspicion. The management of these patients is based on a limited number of randomized clinical trials (RCTs). Early repair of the ruptured aneurysm by endovascular coiling or neurosurgical clipping is essential, and coiling is superior to clipping in cases amenable to both treatments. Aneurysm repair prevents rebleeding, leaving the most important prognostic factors for outcome early brain injury from the hemorrhage, which is reflected in the neurologic condition of the patient, and delayed cerebral ischemia (DCI). Observational studies suggest outcomes are better when patients are managed in specialized neurologic intensive care units with inter- or multidisciplinary clinical groups. Medical management aims to minimize early brain injury, cerebral edema, hydrocephalus, increased intracranial pressure (ICP), and medical complications. Management then focuses on preventing, detecting, and treating DCI. Nimodipine is the only pharmacologic treatment that is approved for SAH in most countries, as no other intervention has demonstrated efficacy. In fact, much of SAH management is derived from studies in other patient populations. Therefore, further study of complications, including DCI and other medical complications, is needed to optimize outcomes for this fragile patient population.

Prediction of vascular abnormalities on CT angiography in patients with acute headache

OBJECTIVES

Patients with acute headache increasingly undergo CT-angiography (CTA) to evaluate underlying vascular causes. The aim of this study is to determine clinical and non-contrast CT (NCCT) criteria to select patients who might benefit from CTA.

METHODS

We retrospectively included patients with acute headache who presented to the emergency department of an academic medical center and large regional teaching hospital and underwent NCCT and CTA. We identified factors that increased the probability of finding a vascular abnormality on CTA, performed multivariable regression analyses and determined discrimination with the c-statistic.

RESULTS

A total of 384 patients underwent NCCT and CTA due to acute headache. NCCT was abnormal in 194 patients. Among these, we found abnormalities in 116 cases of which 99 aneurysms. In the remaining 190 with normal NCCT we found abnormalities in 12 cases; four unruptured aneurysms, three cerebral venous thrombosis', two reversible cerebral vasoconstriction syndromes, two cervical arterial dissections and one cerebellar infarction. In multivariable analysis abnormal NCCT, lowered consciousness and presentation within 6 hr of headache onset were independently associated with abnormal CTA. The c-statistic of abnormal NCCT alone was 0.80 (95% CI: 0.75-0.80), that also including the other two variables was 0.84 (95% CI: 0.80-0.88). If NCCT was normal no other factors could help identify patients at risk for abnormalities.

CONCLUSIONS

In patients with acute headache abnormal NCCT is the strongest predictor of a vascular abnormality on CTA. If NCCT is normal no other predictors increase the probability of finding an abnormality on CTA and diagnostic yield is low.