Extracranial repair of cerebrospinal fluid fistulas

Diagnostic Value of Non-Contrast CT in Cerebrospinal Fluid Leakage After Endoscopic Transnasal Surgery for Sellar and Suprasellar Tumors

We aimed to study the relationship between pneumocephalus on non-contrast CT (NCCT) and post-operative cerebrospinal fluid leakage (p-CFL) after endoscopic transsphenoidal sellar and suprasellar tumor surgeries. Data from patients who underwent endoscopic treatment for sellar or suprasellar tumors from January 2018 to March 2020 were consecutively collected and reviewed. The NCCT pneumocephalus (NP) was measured the first day after operation and the first day after the expansive sponge was extracted. p-CFL was determined according to post-operative clinical symptoms, high resolution CT and glucose test, and expert consensus. Of the 253 patients enrolled in this study, 32 (12.6%) had p-CFL. Compared with patients without p-CFL, patients with p-CFL had a higher occurrence of intra-operative CFL, a longer operation time, a higher rate of pneumocephalus on first-day NCCT after operation (i.e., first-day NP), and a higher rate of NP volume change between two NCCT measurements (referred to as the NP change) (all p < 0.05). In multivariate regression analysis, first-day NP was independently associated with p-CFL occurrence [odds ratio (OR)=6.395, 95% confidence interval (CI)=2.236-18.290, p=0.001). After adding the NP change into the regression model, first-day NP was no longer independently associated with p-CFL, and NP change (OR = 19.457, 95% CI = 6.095–62.107, p<0.001) was independently associated with p-CFL. The receiver operating characteristic curve comparison analysis showed that NP change had a significantly better predicting value than first-day NP (area under the curve: 0.988 vs. 0.642, Z=6.451, p=0.001). NP is an effective imaging marker for predicting p-CFL after endoscopic sellar and suprasellar tumors operation, and the NP change has a better predicting value.

Endoscopic endonasal repair of a cerebrospinal fluid leak secondary to a meningoencephalocele using a posterior – based middle turbinate flap

Cerebrospinal fluid leaks are rare but remain an important differential diagnosis for patients presenting with persistent, unilateral rhinorrhoea. This case describes a middle-aged female with persistent left sided rhinorrhea. She was minimally responsive to treatment for chronic sinusitis. On re-evaluation, a cerebrospinal fluid leak secondary to a meningoencephalocele was identified. This was subsequently repaired with a pedicled, vascularized graft using an endoscopic endonasal approach. The discussion which follows reviews the management of CSF rhinorrhoea with an emphasis on the available surgical options as well as the materials used for repair.

Extensive traumatic anterior skull base fractures with cerebrospinal fluid leak: classification and repair techniques using combined vascularized tissue flaps

OBJECTIVE

This article introduces a classification scheme for extensive traumatic anterior skull base fracture to help stratify surgical treatment options. The authors describe their multilayer repair technique for cerebrospinal fluid (CSF) leak resulting from extensive anterior skull base fracture using a combination of laterally pediculated temporalis fascial-pericranial, nasoseptal-pericranial, and anterior pericranial flaps.

METHODS

Retrospective chart review identified patients treated surgically between January 2004 and May 2014 for anterior skull base fractures with CSF fistulas. All patients were treated with bifrontal craniotomy and received pedicled tissue flaps. Cases were classified according to the extent of fracture: Class I (frontal bone/sinus involvement only); Class II (extent of involvement to ethmoid cribriform plate); and Class III (extent of involvement to sphenoid bone/sinus). Surgical repair techniques were tailored to the types of fractures. Patients were assessed for CSF leak at follow-up. The Fisher exact test was applied to investigate whether the repair techniques were associated with persistent postoperative CSF leak.

RESULTS

Forty-three patients were identified in this series. Thirty-seven (86%) were male. The patients' mean age was 33 years (range 11-79 years). The mean overall length of follow-up was 14 months (range 5-45 months). Six fractures were classified as Class I, 8 as Class II, and 29 as Class III. The anterior pericranial flap alone was used in 33 patients (77%). Multiple flaps were used in 10 patients (3 salvage) (28%)--1 with Class II and 9 with Class III fractures. Five (17%) of the 30 patients with Class II or III fractures who received only a single anterior pericranial flap had persistent CSF leak (p < 0.31). No CSF leak was found in patients who received multiple flaps. Although postoperative CSF leak occurred only in high-grade fractures with single anterior flap repair, this finding was not significant.

CONCLUSIONS

Extensive anterior skull base fractures often require aggressive treatment to provide the greatest long-term functional and cosmetic benefits. Several vascularized tissue flaps can be used, either alone or in combination. Vascularized flaps are an ideal substrate for cranial base repair. Dual and triple flap techniques that combine the use of various anterior, lateral, and nasoseptal flaps allow for a comprehensive arsenal in multilayered skull base repair and salvage therapy for extensive and severe fractures.

Endoscopic repair of a rare basioccipital meningocele associated with recurrent meningitis

Anatomical variants of the basiocciput are uncommon and usually clinically benign. While the majority remain undetected, these anomalies rarely manifest as CSF rhinorrhea or recurrent meningitis associated with meningocele. Compromise of the leptomeninges provides an avenue of ingress for pathological organisms and can lead to recurrent meningitis, necessitating operative repair of the defect to prevent infection. A review of the literature reveals only 3 cases in which a congenital basioccipital defect has been associated with a meningocele requiring surgical repair. The authors present a case of recurrent meningitis in an infant with a congenital basioccipital meningocele treated with a minimally invasive endoscopic technique. At the 2-year follow-up the repair remained successful, with no evidence of recurrence of the meningocele or CSF infection. The literature regarding the etiology and treatment of these lesions was reviewed, with an emphasis on the safety and efficacy of the endoscopic approach. Note that recurrent meningitis in the setting of a skull base defect may indicate the presence of other congenital anomalies that will necessitate multidisciplinary care for a patient's long-term well-being.

Vascularized temporalis muscle flap for the treatment of otorrhea. Technical note

The surgical treatment for cerebral spinal fluid (CSF) fistulas provides closure of the bone and dural defects and prevents the recurrence of brain herniation and CSF fistula. The two main approaches used are the transmastoid and middle fossa ones. The authors review the results of performing a modified middle fossa approach with a vascularized temporalis muscle flap to create a barrier between the repaired dural and bone defects. Fifteen consecutive cases of CSF fistulas treated at the authors' institution were retrospectively reviewed. All patients presented with otorrhea. Eleven patients had previously undergone ear surgery. A middle fossa approach was followed in all cases. The authors used a thin but watertight and vascularly preserved temporalis muscle flap that had been dissected from the medial side of the temporalis muscle and was laid intracranially on the floor of the middle fossa, between the repaired dura mater and petrous bone. The median follow-up period was 2.5 years. None of the patients experienced recurrence of otorrhea or meningitis. There was no complication related to the intracranial temporalis muscle flap (for example, seizures or increased intracranial pressure caused by muscle swelling). One patient developed hydrocephalus, which resolved after the placement of a ventriculoperitoneal shunt 2 months later. The thin, vascularized muscle flap created an excellent barrier against the recurrence of CSF fistulas and also avoided the risk of increased intracranial pressure caused by muscle swelling. This technique is particularly useful in refractory cases.

Surgical treatment of complex traumatic frontobasal lesions: personal experience in 74 patients

OBJECT

The author's personal series included 148 patients who sustained traumatic frontobasal injuries and were treated between 1986 and 1999. Included in this study are 74 of 148 patients with acute injuries and complex frontobasal lesions involving the frontal sinus, the cribriform/ethmoid roof complex, one or both orbital roofs, and the planum sphenoidale.

METHODS

Surgery was delayed for up to 4 weeks postinjury in most patients (67 cases), whereas 17 with space-occupying hematomas and perforating injuries required early surgery. In 30 patients additional surgery was required to treat maxillofacial fractures, which was performed as a one-stage procedure together with the neurosurgical operation. The author performed a standard bifrontal craniotomy in which an intradural or combined intradural-extradural approach was used in all cases. Four patients developed ascending meningitis in the preoperative period. As a result of surgical treatment one patient died, another two patients suffered from permanent defects, and three suffered from transitory neurological worsening. In two patients recurrence of a cerebrospinal fluid fistula occurred within a 3-month period posttreatment but was successfully obliterated during reoperation. In the author's experience the intradural approach is comparable in terms of the morbidity, mortality, and success rates with extracranial approaches; additionally the intradural approach provides full visualization of the intracranial lesion. Useful olfactory nerve function can only be preserved if both olfactory nerves are left intact and not crushed during initial injury; this occurred in only five patients in this series.

CONCLUSIONS

If possible, surgical treatment of more complex lesions should be delayed until the 2nd or 3rd week following traumatic injury. With antibiotic prophylaxis the risk that ascending meningitis will occur prior to surgery is low. If the patient is systemically stable and brain swelling has resolved, even extensive one-stage neurosurgical/maxillofacial procedures are well tolerated.