BACKGROUND: Scalp cirsoid aneurysms are rare subcutaneous arteriovenous fistulae 
affecting the scalp. They can be easily misdiagnosed and mistreated.
OBJECTIVE: To review reported cases of scalp cirsoid aneurysms for their 
incidence, etiology, clinical presentation, treatment, and outcomes using an 
illustrative case.
METHODS: We conducted a PUBMED, SCOPUS, OVID SP, SciELO, and INFORMA search 
using the keywords; "cirsoid," "aneurysm," "arteriovenous," "malformation," 
"scalp," "vascular," and "fistula." We identified 74 pertinent papers, reporting 
242 cases in addition to our reported index case.
RESULTS: Median age at presentation was 25 yr (range 1-72 yr); male to female 
ratio was 2.5:1. The most common symptoms were a pulsatile mass (94% of 
patients), headaches (25%), and tinnitus (20%). The median duration of symptoms 
was 3 yr (6 d to 31 yr), with 60.2% occurring spontaneously, 32.23% traumatic, 
and the rest iatrogenic. A total of 58.5% of cases were managed with surgical 
excision only, 21.6% with endovascular embolization only, and 14.5% with a 
combination of both methods. The complication rate observed in the endovascular 
embolization treatment cohort (55.8%) was significantly higher than that 
observed in the surgical excision only cohort (9.9%) (P < .00001) and in the 
combined therapy cohort (0%) (P < .00001). There is a low recurrence rate after 
treatment irrespective of modality: surgical excision only (6.3%), endovascular 
embolization only (8.3%), and combined therapy (0%).
CONCLUSION: Scalp cirsoid aneurysms are associated with good prognoses when 
recognized and managed appropriately. We suggest combining surgery with 
endovascular embolization as the optimum treatment modality.