Abstract
Background
Pneumocephalus is a rare complication of endoscopic sinus surgery (ESS) and microscopic skull base surgery (MSBS). Postoperatively, patients often present with headache and altered mental status. Unrepaired leaks are associated with an increased risk of ascending meningitis. Standard treatment of pneumocephalus after ESS or MSBS has not been addressed in the literature.
Methods
The study involved a retrospective review of patients at an academic tertiary care center with pneumocephalus after ESS or MSBS.
Results
Ten cases of pneumocephalus were identified, 8 after ESS and 2 after MSBS. Seven ESS defects were very small (<3 mm). The remaining three had defects more than 1 cm. Six of the 8 ESS patients had spontaneous resolution of their cerebrospinal fluid (CSF) leak and pneumocephalus, whereas all patients with larger defects failed conservative therapy with lumbar drainage. Lumbar drainage worsened the pneumocephalus in the MSBS patients. Despite resolution of pneumocephalus in many patients, all were recommended to undergo endoscopic exploration due to concern for increased risk of meningitis in unrepaired defects. Endoscopic repair was necessary in 8 cases. Repairs required a mucosal graft with or without a bone graft. Many spontaneously healed defects were found to be very tenuous. In 2 cases, patients were found to have dense scar over the defect not requiring repair.
Conclusions
In patients with pneumocephalus after ESS or MSBS, consideration should be given to endoscopic exploration and repair of the defect with mucosal grafting. Even if spontaneous resolution has occurred, there may be increased risk of ascending meningitis through the thin or incompletely regenerated mucosa.
1
Introduction
Intracranial complications of endoscopic sinus surgery (ESS) are fortunately very rare, occurring in less than 1% of cases . The most common intracranial complication is cerebrospinal fluid (CSF) leak . The presence of CSF rhinorrhea is a potential risk factor for ascending meningitis, which may occur in up to one third of patients . Pneumocephalus as a result of intranasal surgery is quite rare. It is infrequently seen after open skull base surgery, less so after microscopic skull base surgery, and rarely after ESS. Risk factors include skull base injury and positive pressure events in the postoperative period such as coughing, straining, or vomiting. Patients with concomitant pneumocephalus may have an increased risk of meningitis . Overall incidence of meningitis as a complication of skull base defect and CSF leak ranges from 9% to 50% with a reported cumulative risk of 85% at 10 years if no repair is performed . There is no report in the literature on appropriate treatment of pneumocephalus after ESS or MSBS.
2
Materials and methods
A retrospective review was performed of patients with pneumocephalus who presented to the senior author (JMD). Inclusion criteria were evidence of pneumocephalus after ESS or MSBS. Patient demographics, type of procedure performed, presenting symptoms, and size of the defect were collected. We also evaluated whether a lumbar drain was used and how this affected the pneumocephalus. The overall outcome was also evaluated.
2
Materials and methods
A retrospective review was performed of patients with pneumocephalus who presented to the senior author (JMD). Inclusion criteria were evidence of pneumocephalus after ESS or MSBS. Patient demographics, type of procedure performed, presenting symptoms, and size of the defect were collected. We also evaluated whether a lumbar drain was used and how this affected the pneumocephalus. The overall outcome was also evaluated.
3
Results
Ten cases of pneumocephalus after ESS (8 patients) and MSBS (2 patients) were identified ( Table 1 ). All of the procedures were primary transnasal procedures, with none being revision operations. The indications for surgery were chronic sinusitis in 7 patients, invasive fungal sinusitis, pituitary macroadenoma ( Fig. 1 ), and planum sphenoidale meningioma. None of the ESS patients had anatomical risk factors that increased the risk of skull base injury. In fact, only 1 of 8 patients had opacification of the sinuses at the site of the subsequent defect, whereas the other 6 had none to mild disease. Only 1 patient had a distinct positive pressure episode in the postoperative period, with a bout of emesis before the onset of headache (patient 1). All patients had onset of symptoms within 1 week of their transnasal surgery.
| Patient | Age/sex | Presenting symptom | Initial surgery | Interval to exploration (d) | Resolution of pneumocephalus/CSF leak before repair | Defect size | Lumbar drain used/result |
|---|---|---|---|---|---|---|---|
| 1 | 45/Female | Headache | ESS | 20 | Yes | 2 mm | No/– |
| 2 | 67/Female | Headache | ESS | 40 | Yes | 2 mm | No/– |
| 3 | 62/Male | Headache | ESS | 21 | Yes | 1 mm | No/– |
| 4 | 67/Male | Mental status change | ESS | 90 | Yes | 3 mm | No/– |
| 5 | 44/Male | Headache | ESS | 21 | No | 15 mm | Yes/no improvement |
| 6 | 56/Male | Rhinorrhea, fixed globe | ESS | 742 | Yes | 3 mm | No/– |
| 7 | 40/Male | Headache, rhinorrhea | ESS | 2 | No | 3 mm | No/– |
| 8 | 25/Male | Headache | Transsphenoidal pituitary | 28 | No | 16 mm | Yes/worsened |
| 9 | 57/Female | Mental status change | Planum sphenoidale meningioma | 54 | Yes, trach | 15 mm | Yes/worsened |
| 10 | 53/Male | Headache, meningitis | ESS, septoplasty | 910 | Yes/no | 3 mm | No |
Presenting symptoms included headache with clear rhinorrhea in all 10 patients and mental status changes in 2 patients. Most of the patients had mild to moderate amounts of intracranial air ( Fig. 2 ). The 2 patients with mental status changes had tension pneumocephalus (patients 4 and 9) ( Fig. 3 ). One patient who underwent ESS and septoplasty presented with pneumocephalus, CSF rhinorrhea, and meningitis.
