Presidential spokesman Alfredo Scoccimarro told reporters and well-wishers outside the Favaloro Foundation clinic where the operation was performed Fernandez was "in [a] very good mood" and "she thanked the medical team and all the people" who have expressed their support for her.
The Buenos Aires Herald reported hundreds of her backers held a vigil outside the clinic and celebrated when Scoccimarro delivered the update.
The newspaper said messages of encouragement were displayed outside the Buenos Aires hospital.
Fernandez had suffered a subdural hematoma in mid-August that caused headaches, and initially her doctors recommended she take a 30-day leave of absence to rest. The physicians decided the 60-year-old president needed surgery following additional tests after she felt a tingling sensation in her left arm Sunday.
Her administration has not divulged what caused the hematoma.
Vice President Amado Boudou is handling the presidential duties until Fernandez can return to work.
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