Children who survive a brain abscess may be left with seizures, permanent motor or sensory deficits, personality changes, or visual field defects (55).
- Unappreciated brain shift during procedure: Stereotactic puncture is a blind surgical maneuver in which the lack of direct visual control is an obvious disadvantage. Untoward adverse events may occur, such as the capsule collapsing after pus aspiration, causing the catheter to slip out of the abscess cavity (requiring replacement).
- Hemorrhage: During stereotactic puncture, needle trajectory may cause vascular damage and result in intraparenchymal hemorrhage.
- Contamination of CSF space: The abscess may rupture into the ventricle or subarachnoid space (needle trajectory through the ventricular system, while aspirating the abscess).
- Increased risk of wound infections (32)
- Recurrence: Medical management alone of large abscesses is usually inadequate and tends to lead to recurrence (51). The lack of appropriate antimicrobial coverage for the abscess and/or failure to treat the sources of the infection can predispose patients to recurrence (51).
- Declining sequalae with modern management: The impairment of neurological functions from cerebral abscess has declined from 16–52% in most large series before 1975 to about 4–27% in series published after 1975. The use of stereotactically guided aspiration, with its limited damage to the surrounding brain, is believed by some experts to be responsible for a portion of this improvement (30, 117).
- 70% have cognitive sequelae: Seventy percent of children who survive a brain abscess have been found to have long-term cognitive and school difficulties (20, 24).
- 10–59% have chronic seizures: Epilepsy is a common initial and long-term sequela of brain abscesses in children. Seizures occur in 30–45% of children at presentation and are chronic in 10–59% of reported series in children (55).
- Onset of seizures delayed: In a majority of children with brain abscesses, the onset of seizures is delayed, with only 50% occurring within the first year after treatment (20). It has been reported that initial seizures appear to occur after a longer latency period in children younger than 10 years, with a mean latency period of approximately 3 years, and anticonvulsant agents are generally efficacious in controlling those seizures (90).
- Higher incidence of seizures in supratentorial abscesses: The high incidence of seizures in children with supratentorial brain abscesses means that prophylactic anticonvulsants are indicated for 1 or 2 years, after which they can be withdrawn if the EEG shows no further epileptogenic activity (30).
- Recurrence risk increased with stereotactic aspiration, fungal infections, occult source, or medically managed traumatic abscess: Abscess recurrence is more common after aspiration than surgical extirpation. The incidence after stereotactic aspiration ranges from 3–25% compared with 0–6% after excision (51). Recurrence is most common after aspiration of fungal abscesses, in which the infecting organism may be present in the capsule, or in the case of nocardial lesions. Excision is recommended for such lesions (30). Brain abscesses secondary to cranial trauma tend to recur if surgical excision is not performed because the bone fragments and/or foreign bodies are retained. The proportion of abscesses that recur when the source of the brain abscess is not found is 10–37%, and this rate increases if cultures demonstrate no growth.