ABSTRACT
INTRODUCTION: For postoperative CSF-fistula prevention a better understanding of its origins and risk factors is necessary. To identify the role of the tumor growth for the risk to develop CSF-fistula we performed a retrospective analysis. METHODS: 519 patients between the years 2000 and 2007 had a retrosigmoidal surgical removal of vestibular schwannoma in a standardized procedure. 22 CSF-fistula-patients were chosen for evaluation. 78 patients were randomly selected as control group in four equally sized cohorts: male/female with small/large tumors. Preoperative CT-scans were analyzed regarding IAC-length, diameter of the IAC porus (IAP), tumor size and pneumatization of the posterior wall (PW) of the IAC. RESULTS: The mean length of the IAC was 1.2 cm, SD 0.17. There was a significant difference between the diameter of the IAP in cases of small tumors and those of large tumors. Patients with small tumors also showed a larger fraction with visible pneumatization of the PW (34.88%) in the CT-scan than patients with large tumors (24.07%). There is a positive correlation between tumor grade and diameter of the IAP. At the same time there is an inverse correlation between tumor grade and pneumatization of the PW. CONCLUSIONS: Widening of the IAC by tumor growth may leads to obliteration of air cells in the PW and therefore can be protective concerning CSF-fistula. At the same time patients with small tumors and a visible pneumatization in the PW must be expected to have a higher risk of CSF-fistula.
Subject(s)
Cerebrospinal Fluid Rhinorrhea/etiology , Cranial Sinuses/pathology , Fistula/etiology , Neuroma, Acoustic/complications , Neuroma, Acoustic/surgery , Postoperative Complications/etiology , Adolescent , Adult , Aged , Cerebrospinal Fluid Rhinorrhea/epidemiology , Cohort Studies , Craniotomy , Ear Canal/pathology , Female , Fistula/epidemiology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neuroma, Acoustic/pathology , Neurosurgical Procedures , Petrous Bone/diagnostic imaging , Petrous Bone/pathology , Postoperative Complications/epidemiology , Retrospective Studies , Risk , Tomography, X-Ray Computed , Young AdultABSTRACT
BACKGROUND: For the prevention of postoperative CSF fistula a better understanding of origins and risk factors is necessary. OBJECTIVE: To identify the petrous bone air cell volume as a risk factor for developing CSF fistula, we performed a retrospective analysis. METHODS: From 2000 to 2007 519 patients had a retrosigmoidal surgical removal of a vestibular schwannoma. The 22 who had a postoperative CSF fistula were chosen for evaluation in addition to 78 patients who were randomly selected in 4 equally sized cohorts: male/female with small/large tumors. Preoperative CT scans were analyzed regarding petrous bone air cell volume, area of visible pneumatization at the level of the internal auditory canal (IAC), tumor grade, and sex. RESULTS: : Women developed nearly half as many CSF fistulas (2.7%) as men (5.2%). The mean volume of the petrous bone air cells was 10.97 mL (SD, 4.9; range, 1.38-27.25). It was significantly lower for women (mean, 9.23 mL; SD, 3.8) than for men (mean, 12.5 mL; SD, 5.28; P = .0008). The mean air cell volume of CSF-fistula patients was 13.72 mL (SD, 5.22). The difference concerning the air cell volume between patients who developed CSF fistulas and patients from the control group was significant (P = .0042). There was a significant positive correlation between the air cell volume and the area of pneumatization in one CT slide at the level of the IAC. CONCLUSION: The higher incidence of CSF fistulas in men compared with women can be explained by means of differently pneumatized petrous bones. A high amount of petrous bone pneumatization has to be considered as a risk factor for the development of postoperative CSF fistula after vestibular schwannoma surgery.
Subject(s)
Cerebrospinal Fluid Rhinorrhea/etiology , Neuroma, Acoustic/surgery , Petrous Bone/abnormalities , Petrous Bone/surgery , Postoperative Complications/etiology , Adult , Aged , Cerebrospinal Fluid Leak , Cerebrospinal Fluid Rhinorrhea/prevention & control , Cohort Studies , Female , Humans , Male , Middle Aged , Petrous Bone/diagnostic imaging , Radiography , Retrospective Studies , Risk FactorsABSTRACT
We conducted virologic investigations on postmortem specimens from 261 free-living European bison (Bison bonasus) from the Bialowieza Primeval Forest, Poland collected between 1990 and 2000. Fifty-four of 94 males had balanoposthitis; none of the 167 female bison examined had reproductive tract lesions. Peripheral blood, swabs, and various tissues were analyzed for bovine viruses as well as for viral DNA by bovine herpesvirus 1 (BoHV-1) and bovine herpesvirus 4 (BoHV-4) specific polymerase chain reaction (PCR) technique. An infectious bovine rhinotracheitis like BoHV-1 strain was isolated from the spleen of a female bison calf and additionally was detected by nested PCR from splenic tissue. None of the bison had significant antibody titers against BoHV-1, bovine herpesvirus 2, BoHV-4, caprine herpesvirus 1, cervid herpesvirus 1, or bovine viral diarrhea (BVD) virus-1. However, low antibody titers in two animals indicate that this European bison population has been exposed to BVD virus or BVD-like viruses and BoHV-2.
