Postoperative management after cerebrospinal fluid leak repair in patients with idiopathic intracranial hypertension

Imaging

In patients undergoing surgical management of a skull base encephalocele and spontaneous CSF leak, postoperative day (POD) 1 imaging can aid in evaluation of potential postsurgical sequelae. However, several retrospective studies have suggested that early imaging is of limited benefit because most positive imaging findings are preceded by clinical symptoms. ^, If the encephalocele or defect is large or fibrous or if there is tugging during the procedure, POD 1 computed tomography (CT) of the head is useful to evaluate for any intracranial hemorrhage as a result of the brain manipulation. Postoperative imaging is also useful in patients with altered mental status to rule out pneumocephalus (if more than expected postoperatively), adequacy of packing and contact to the skull base, or hemorrhage or evolution of known hemorrhage or to obtain a new baseline image. Likewise, magnetic resonance imaging (MRI) can be undertaken for further evaluation of the brain if there are concerns regarding possible postoperative complications.

In long-term follow-up, CT scans may be obtained to ensure no further areas of skull base thinning or defect as well as adequate healing and integration of the ridge graft, if used at the time of repair.

Expectations

Postoperatively, patients have blood and mucus drain from the nasal cavity. This may worsen the first time the patient ambulates as fluid continues to mobilize. In patients in whom extensive flaps have been raised, serous drainage may be increased and persist beyond the first few days. Blood-tinged mucus secretions are expected for the first week after surgery with improvements in quantity after the first 3 to 5 days.

Any nasal drainage after CSF leak repair can lead to concern regarding persistent CSF leak. However, health care professionals involved in the perioperative management of patients undergoing skull base repairs need to understand the expected nasal discharge and clinical status of postsurgical patients. The presence of CSF leak in these patients is considered a clinical diagnosis, and repeat β2 transferrin should be avoided at this time. Simply collecting any fluid that comes from a patient’s nose in the first 7 days after surgery is likely to give a false positive reading. ^, Patients with true failure and leakage have low-pressure headaches and present with worsening headaches when upright and improvement when lying flat. This can occur from the surgical site, or in cases when a lumbar drain or puncture has been used, the patient can leak from the lumbar puncture site. Patients who leak CSF from the lumbar puncture site often require placement of a blood patch. In some instances, a short trial of bedrest can be attempted before blood patch placement.

Patients with a recurrent or persistent CSF leak after repair or in whom recent repair has occurred (instrumentation across a violated dura) are at risk for developing meningitis. Overall, meningitis after skull base surgery is rare and is more often associated with open craniofacial surgery or persistent CSF leaks. Fewer than half of adults with bacterial meningitis present with the typical triad of fever, headache, and neck stiffness. However, most patients exhibit two of four possible symptoms (fever, headache, stiff neck, and altered mental status). Other symptoms may also be present, including nausea, vomiting, photalgia, sleepiness, confusion, irritability, delirium, or coma. In patients already on antibiotic therapy, it can take longer for symptoms to present, and symptoms can be less intense. Of note, patients with ventriculitis after ventriculoperitoneal (VP) shunt placement or recent cranial surgery may also have a less dramatic presentation. In patients in whom meningitis is suspected, diagnosis requires a lumbar puncture. However, given the potential risk of brain herniation, a screening CT scan of the head can be performed. Certain patients are at higher risk of herniation (age older than 60 years, immunocompromised, history of central nervous system disease, seizure 1 week before presentation, neurologic changes on examination). Antibiotic treatment should not be withheld while awaiting screening CT. Meningitis workup also includes blood cultures, complete blood counts, serum electrolytes, and a basic metabolic panel. If the patient is currently taking ceftriaxone, then broadening coverage with vancomycin is recommended. In patients who have undergone recent neurosurgical intervention or placement of a shunt, vancomycin and ceftazidime, cefepime, or meropenem is recommended as empiric treatment.