The Role of digital subtraction angiography in the ventricular spot sign on the computed tomography angiography

Abstract

Objective: The spot sign on computed tomography angiography is little known about the relationship between the spot sign and the results of cerebral angiography We retrospectively analyzed the spot sign, digital subtraction angiography results, and other factors.

Material and methods: From December 2009 to May 2014, DSA was performed in 52 ICH patients with non-specific location or abnormalities on CTA findings. 26 of those patients, whose initial CTA showed the spot sign, were analyzed. Two groups, one with the spot sign in the ventricle (Group A) and others with the spot sign in another location (Group B) were statistically compared.

Results: The mean age of the study subjects was 46.9 years (range, 15 to 80 years) and the percentage of males was 53.8%. Thirteen of 26 patients had ICH without intraventricular hemorrhage, and 6 patients had co-existing IVH. In 17 cases, the DSA results were negative. Seven patients were diagnosed with pseudoaneurysms, and two cases showed developmental venous anomalies. Group A consisted of the 8 patients (30.8%) who showed the spot sign in a ventricle. The number of pseudoaneurysms was statistically significantly higher in Group A than in Group B (71.4% versus 28.6%; OR, 13.3; 95% CI, 1.7-103.8 P = 0.014). All three patients who underwent endovascular treatment were members of Group A (P = 0.022), whereas most (92.3%) of those in Group B underwent surgical evacuation. (P = 0.030).

Conclusion: When CTA shows the spot sign in a ventricle, it is a clue that an existing underlying vascular lesion requires endovascular treatment.

Keywords: Cerebral angiography; Cerebral hemorrhage; computed tomography angiography; spot sign.

Fig. 1. A 54-year-old male (A) Non-enhanced computed tomography (NECT) shows a left frontal ICH. (B) Hyperdensity apparent on a post contrast CT image (black arrow), called the ‘spot sign,’ is detected. There is no definite vascular abnormality on DSA. (C) A follow-up brain CT shows expansion of the hematoma

Fig. 2. A 46-year-old female with a developmental venous anomaly. (A) A NECT demonstrate ICH in the left cerebellum. (B) The CTA shows the ‘spot sign’ (black arrow) within the hematoma. (C) An umbrella-shaped collection of dilated medullary veins, the so-called ‘caput medusae’ with a dilated transcortical vein (white arrow) is detected during the venous phase of the DSA.

Fig. 3. A 58-year-old male with a pseudoaneurysm (A) NECT demonstrate pure IVH (B) CTA shows the spot sign (black arrow) in the right lateral ventricle. (C) A vertebral angiogram (lateral view) shows a pseudoaneurysm (white arrow) in the right posterior choroidal artery. (D) After embolization with glue, there is no more contrast filling in the pseudoaneurysm on DSA (White arrowhead).

Fig. 4. A 15-year-old female with a pseudoaneurysm (A) NECT shows ICH in the right frontal lobe with IVH. (B) CTA shows the spot sign (black arrow) within the hematoma. (C) DSA (AP view) reveals an AVM with a pseudoaneurysm (white arrow). (D) After surgical treatment, there is no hematoma or pseudoaneurysm that showed contrast filling on the CTA MIP image (the white arrowhead is a post-operation hemo-clip).