The Neuroradiology Journal 20: 642-645, 2007
www. centauro. it
CT-Cisternography in Post-Surgical CSF Rhinorrhea. A Report of Two Cases
L. PASQUALETTO, G. LA TESSA, L. DE BELLIS, A. PAONESSA, G. IANNACCONE*, M. DE BELLIS*, G. SIRABELLA Department of Neuroradiology, * Department of Neurosurgery, Santa Maria di Loreto Nuovo Hospital; Naples Italy.
Key words: rhinorrhea, CT cisternography
SUMMARY – Cerebrospinal fluid (CSF) rhinorrhea is a dangerous problem. CSF rhinorrhea implies an abnormal communication between the subarachnoid space and the nasal cavity, with subsequent leakage of CSF through the anterior nasal apertures. requiring surgical repair. Imaging techniques have evolved from conventional cranial radiography to polytomography, thin-section computed tomography (CT) and intrathecal water-soluble iodinated contrast agent-enhanced CT cisternography. We present two cases of post-surgical CSF rhinorrhea in which the best diagnostic findings were obtained by CT cisternography.
Introduction
Case 2
Cerebrospinal fluid (CSF) rhinorrhea is a dangerous problem. Persistent CSF leak may lead to meningitis or abscess and requires surgical repair. The standard diagnostic technique to localize the CSF leakage is computed tomography (CT) cisternography. We present two cases of post-surgical CSF rhinorrhea in which the best diagnostic findings were obtained by CT cisternography.
A 60-year-old man underwent surgical intervention for bilateral polyposis. An intermittent CSF rhinorrhea occurred a few days after surgery. For this reason the patient had a new surgical operation with transnasal approach to identify and remove the probable leakage. CSF rhinorrhea occurred some years later discontinuously. So our CT cisternography revealed two possible CSF leakages in the right posterior ethmoid cells. Surgical exploration confirmed the presence of the two bone defects that were repaired.
Case 1 A 58-year-old man presented with a history of head trauma ten years earlier. A subsequent CT demonstrated a mucocele of the frontal sinus. He underwent surgical intervention for mucocele two years after the diagnosis. The patient noticed watery discharge from a nostril three months after he was discharged from the hospital. He also had another two unsuccessful surgical operations for a presumed defect in the floor of the anterior cranial fossa before our admission. A CT cisternography demonstrated a CSF leak (figure 1) that was repaired by surgical intervention. 642
Discussion CSF rhinorrhea implies an abnormal communication between the subarachnoid space and the nasal cavity, with subsequent leakage of CSF through the anterior nasal apertures. Park classified CSF as traumatic, non-traumatic or post-surgical in origin 1. Successful surgical repair of cerebrospinal fluid (CSF) leaks depends on accurate preoperative localization of the site of the defect. Precise localization of a CSF fistula helps in
L. Pasqualetto
A
CT-Cisternography in Post-Surgical CSF Rhinorrhea
B
Figure 1 CT cisternography: small CSF fistula in the anterior cranial fossa.
A
B
C
Figure 2 Post-surgical CT: point of fistula repaired by semifluid hydroxyapatite (Cortos).
643
CT-Cisternography in Post-Surgical CSF Rhinorrhea
surgical planning and enhances the chances of a successful dural repair. Imaging techniques have evolved from conventional cranial radiography to polytomography, thin-section computed tomography (CT) and intrathecal water-soluble iodinated contrast agent-enhanced CT cisternography 2. CT cisternography was introduced in 1977 3 and to date has been considered the standard of reference for diagnosis of CSF fistula 4. Detection of fistulas has been reported with an accuracy ranging from 22% to 100 % 5 with a high rate of fistula detection reported when there was active CSF leak during the diagnostic procedure. The most common site of a CSF fistula is through the floor of the anterior cranial fossa, which communicates with the ethmoid or frontal sinuses or with the nasal fossa. The sphenoid sinus is rarely implicated as a source of spontaneous CSF fistula 6. In the two patients presented here the following procedures were used for the diagnosis and precise location of dural defects. Watery nasal secretions were examined for the presence of CSF using glucose determination and measurement of β2 transferrin 7. For the CT cisternography, 5 ml of non-ionic iodinate contrast material (370 mgl/mL) was injected intrathecally via a lumbar puncture. The scan was performed on a multislice Philips MX 8000 CT scanner from nasion to dorsum sellae with a 1 mm slice thickness and 1 mm intervals. Post-processing (Multiplanar Reconstruction MPR and Volume rendering VR imaging) performed by Tiani J-Vision Workstation, permitted better visualization in the coronal and sagittal planes of bony defects of the ethmoid roof, the cribriform plate, and the roof of the sphenoid sinus, while imaging in the axial plane had advantages for evaluation of the posterior wall of the frontal sinus and the lateral walls of the sphenoid sinus. However, contrast-enhanced CT cisternogra-
L. Pasqualetto
phy is not without risk of side effects, including headache, nausea, vomiting, seizures, allergic reaction and rarely intracerebral hemorrhage 8. Furthermore, it is contraindicated in patients with active meningitis, high intracranial pressure and in those with spinal disorders. The technique is invasive and poorly tolerated by patients. Hence magnetic resonance imaging (MRI) cisternography, depending on heavily fat-suppressed T2-weighted sequences, can non-invasively demonstrate a CSF-like presence in multiple planes in these patients without the disadvantage of ionizing radiation. Its accuracy in patients with active CSF rhinorrhea is 86% 4. The primary disadvantages of MRI are its poor spatial resolution compared with CT cisternography and the absence of bony details 9. In our cases unenhanced CT had failed to demonstrate any leakage and no other procedures were used to diagnose the CSF. However CT cisternography permitted precise preoperative identification of CSF fistulas. The site of CSF leakage was surgically identified by direct visualization of a dural/bone defect and the use of semifluid hydroxyapatite (Cortos) allowed us to repair the fistulas (figure 2) and to resolve the CSF rhinorrhea. Lumbar cerebrospinal fluid drainage for eight days was applied and no side-effects were noted. Both the first and the second patient were free of rhinorrhea from the day of the surgical intervention. Conclusion Intrathecal contrast CT cisternography is an efficacious imaging technique that may permit direct and sensitive visualization of the site of post-surgical CSF leakage. It should be the examination of choice in rhinorrhea patients since it reduces the risks of surgical recurrences by displaying the exact location of the fistula.
References 1 Park J, Strelzow V, Friedman W: Current management of cerebrospinal fluid rhinorrhea. Laryngoscope 93: 1924-1300, 1983. 2 Stone JA, Castillo M, Neelon B et Al: Evaluation of CSF leaks: high-resolution CT compared with contrast enhanced CT and radionuclide cisternography. Am J Neuroradiol 20: 706-712, 1999. 3 Drayer BP, Wilkins RH, Boehnke M et Al: Cerebrospinal fluid rhinorrhea demonstrated by metrizamide CT cisternography. AJR Am. J Roentgenol 129: 149-151, 1977.
644
4 Shetty PG, Shroff MM, Sahani DV et Al: Evaluation of high-resolution CT and MR cisternography in the diagnosis of cerebrospinal fluid fistula. Am J Neuroradiol 19: 633-639, 1998. 5 Chow JM, Goodman D, Mafee MF: Evaluation of CSF rhinorrhea by computerized tomography with metrizamide. Otolaryngol Head Neck Surg 100: 99-105, 1989. 6 Landrenean FE, Mickey B, Coimbra C: Surgical treatment of cerebrospinal fluid fistula involving lateral extension of the sphenoid sinus. Neurosurgery 42: 11011105, 1998.
www. centauro. it
7 Oberascher G: A modern concept of cerebrospinal fluid diagnosis in oto- and rhinorrhea. Rhinology 26: 89-103, 1988. 8 Jinkins JR , Rudwan M, Krumina G et Al: Intrathecal gadolinium-enhanced MR cisternography in the evaluation of clinically suspected cerebrospinal fluid rhinorrhea in humans: early experience. Radiology 222: 555559, 2002. 9 Mostafa BE, Khafagi A: Combined HRCT and MRI in the detection of CSF rhinorrhea. Skull Base 14: 157162, 2004.
The Neuroradiology Journal 20: 642-645, 2007
Dr L. Pasqualetto Neuroradiology Department Santa Maria di Loreto Nuovo Hospital via Amerigo Vespucci 80100 Naples, Italy Tel.: +39 333 7422037 Fax: +39 081 2542756 E-mail: [email protected]
645
www. centauro. it
CT-Cisternography in Post-Surgical CSF Rhinorrhea. A Report of Two Cases
L. PASQUALETTO, G. LA TESSA, L. DE BELLIS, A. PAONESSA, G. IANNACCONE*, M. DE BELLIS*, G. SIRABELLA Department of Neuroradiology, * Department of Neurosurgery, Santa Maria di Loreto Nuovo Hospital; Naples Italy.
Key words: rhinorrhea, CT cisternography
SUMMARY – Cerebrospinal fluid (CSF) rhinorrhea is a dangerous problem. CSF rhinorrhea implies an abnormal communication between the subarachnoid space and the nasal cavity, with subsequent leakage of CSF through the anterior nasal apertures. requiring surgical repair. Imaging techniques have evolved from conventional cranial radiography to polytomography, thin-section computed tomography (CT) and intrathecal water-soluble iodinated contrast agent-enhanced CT cisternography. We present two cases of post-surgical CSF rhinorrhea in which the best diagnostic findings were obtained by CT cisternography.
Introduction
Case 2
Cerebrospinal fluid (CSF) rhinorrhea is a dangerous problem. Persistent CSF leak may lead to meningitis or abscess and requires surgical repair. The standard diagnostic technique to localize the CSF leakage is computed tomography (CT) cisternography. We present two cases of post-surgical CSF rhinorrhea in which the best diagnostic findings were obtained by CT cisternography.
A 60-year-old man underwent surgical intervention for bilateral polyposis. An intermittent CSF rhinorrhea occurred a few days after surgery. For this reason the patient had a new surgical operation with transnasal approach to identify and remove the probable leakage. CSF rhinorrhea occurred some years later discontinuously. So our CT cisternography revealed two possible CSF leakages in the right posterior ethmoid cells. Surgical exploration confirmed the presence of the two bone defects that were repaired.
Case 1 A 58-year-old man presented with a history of head trauma ten years earlier. A subsequent CT demonstrated a mucocele of the frontal sinus. He underwent surgical intervention for mucocele two years after the diagnosis. The patient noticed watery discharge from a nostril three months after he was discharged from the hospital. He also had another two unsuccessful surgical operations for a presumed defect in the floor of the anterior cranial fossa before our admission. A CT cisternography demonstrated a CSF leak (figure 1) that was repaired by surgical intervention. 642
Discussion CSF rhinorrhea implies an abnormal communication between the subarachnoid space and the nasal cavity, with subsequent leakage of CSF through the anterior nasal apertures. Park classified CSF as traumatic, non-traumatic or post-surgical in origin 1. Successful surgical repair of cerebrospinal fluid (CSF) leaks depends on accurate preoperative localization of the site of the defect. Precise localization of a CSF fistula helps in
L. Pasqualetto
A
CT-Cisternography in Post-Surgical CSF Rhinorrhea
B
Figure 1 CT cisternography: small CSF fistula in the anterior cranial fossa.
A
B
C
Figure 2 Post-surgical CT: point of fistula repaired by semifluid hydroxyapatite (Cortos).
643
CT-Cisternography in Post-Surgical CSF Rhinorrhea
surgical planning and enhances the chances of a successful dural repair. Imaging techniques have evolved from conventional cranial radiography to polytomography, thin-section computed tomography (CT) and intrathecal water-soluble iodinated contrast agent-enhanced CT cisternography 2. CT cisternography was introduced in 1977 3 and to date has been considered the standard of reference for diagnosis of CSF fistula 4. Detection of fistulas has been reported with an accuracy ranging from 22% to 100 % 5 with a high rate of fistula detection reported when there was active CSF leak during the diagnostic procedure. The most common site of a CSF fistula is through the floor of the anterior cranial fossa, which communicates with the ethmoid or frontal sinuses or with the nasal fossa. The sphenoid sinus is rarely implicated as a source of spontaneous CSF fistula 6. In the two patients presented here the following procedures were used for the diagnosis and precise location of dural defects. Watery nasal secretions were examined for the presence of CSF using glucose determination and measurement of β2 transferrin 7. For the CT cisternography, 5 ml of non-ionic iodinate contrast material (370 mgl/mL) was injected intrathecally via a lumbar puncture. The scan was performed on a multislice Philips MX 8000 CT scanner from nasion to dorsum sellae with a 1 mm slice thickness and 1 mm intervals. Post-processing (Multiplanar Reconstruction MPR and Volume rendering VR imaging) performed by Tiani J-Vision Workstation, permitted better visualization in the coronal and sagittal planes of bony defects of the ethmoid roof, the cribriform plate, and the roof of the sphenoid sinus, while imaging in the axial plane had advantages for evaluation of the posterior wall of the frontal sinus and the lateral walls of the sphenoid sinus. However, contrast-enhanced CT cisternogra-
L. Pasqualetto
phy is not without risk of side effects, including headache, nausea, vomiting, seizures, allergic reaction and rarely intracerebral hemorrhage 8. Furthermore, it is contraindicated in patients with active meningitis, high intracranial pressure and in those with spinal disorders. The technique is invasive and poorly tolerated by patients. Hence magnetic resonance imaging (MRI) cisternography, depending on heavily fat-suppressed T2-weighted sequences, can non-invasively demonstrate a CSF-like presence in multiple planes in these patients without the disadvantage of ionizing radiation. Its accuracy in patients with active CSF rhinorrhea is 86% 4. The primary disadvantages of MRI are its poor spatial resolution compared with CT cisternography and the absence of bony details 9. In our cases unenhanced CT had failed to demonstrate any leakage and no other procedures were used to diagnose the CSF. However CT cisternography permitted precise preoperative identification of CSF fistulas. The site of CSF leakage was surgically identified by direct visualization of a dural/bone defect and the use of semifluid hydroxyapatite (Cortos) allowed us to repair the fistulas (figure 2) and to resolve the CSF rhinorrhea. Lumbar cerebrospinal fluid drainage for eight days was applied and no side-effects were noted. Both the first and the second patient were free of rhinorrhea from the day of the surgical intervention. Conclusion Intrathecal contrast CT cisternography is an efficacious imaging technique that may permit direct and sensitive visualization of the site of post-surgical CSF leakage. It should be the examination of choice in rhinorrhea patients since it reduces the risks of surgical recurrences by displaying the exact location of the fistula.
References 1 Park J, Strelzow V, Friedman W: Current management of cerebrospinal fluid rhinorrhea. Laryngoscope 93: 1924-1300, 1983. 2 Stone JA, Castillo M, Neelon B et Al: Evaluation of CSF leaks: high-resolution CT compared with contrast enhanced CT and radionuclide cisternography. Am J Neuroradiol 20: 706-712, 1999. 3 Drayer BP, Wilkins RH, Boehnke M et Al: Cerebrospinal fluid rhinorrhea demonstrated by metrizamide CT cisternography. AJR Am. J Roentgenol 129: 149-151, 1977.
644
4 Shetty PG, Shroff MM, Sahani DV et Al: Evaluation of high-resolution CT and MR cisternography in the diagnosis of cerebrospinal fluid fistula. Am J Neuroradiol 19: 633-639, 1998. 5 Chow JM, Goodman D, Mafee MF: Evaluation of CSF rhinorrhea by computerized tomography with metrizamide. Otolaryngol Head Neck Surg 100: 99-105, 1989. 6 Landrenean FE, Mickey B, Coimbra C: Surgical treatment of cerebrospinal fluid fistula involving lateral extension of the sphenoid sinus. Neurosurgery 42: 11011105, 1998.
www. centauro. it
7 Oberascher G: A modern concept of cerebrospinal fluid diagnosis in oto- and rhinorrhea. Rhinology 26: 89-103, 1988. 8 Jinkins JR , Rudwan M, Krumina G et Al: Intrathecal gadolinium-enhanced MR cisternography in the evaluation of clinically suspected cerebrospinal fluid rhinorrhea in humans: early experience. Radiology 222: 555559, 2002. 9 Mostafa BE, Khafagi A: Combined HRCT and MRI in the detection of CSF rhinorrhea. Skull Base 14: 157162, 2004.
The Neuroradiology Journal 20: 642-645, 2007
Dr L. Pasqualetto Neuroradiology Department Santa Maria di Loreto Nuovo Hospital via Amerigo Vespucci 80100 Naples, Italy Tel.: +39 333 7422037 Fax: +39 081 2542756 E-mail: [email protected]
645
