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Endoscopic repair of cerebrospinal fluid rhinorrhea
Endoscopic repair of cerebrospinal fluid rhinorrhea VIVIAN H. MAO, MD, WILLIAM M. KEANE, MD, JOSEPH P. ATKINS, MD, JOSEPH R. SPIEGEL, MD, THOMAS O. WILLCOX, MD, MARC R. ROSEN, MD, DAVID ANDREWS, MD, and DAVID ZWILLENBERG, MD, Philadelphia, Pennsylvania
Endoscopic repair of cerebrospinal fluid rhinorrhea is a promising alternative to traditional repair techniques. This article reports our experience with 21 cases (10 spontaneous, 8 iatrogenic, and 3 traumatic). Various diagnostic radiographic modalities were used, including computer-aided techniques. Most repairs were accomplished with a free fascial graft positioned in the epidural space. Postoperative lumbar drainage was used in 15 cases. Initial repair was successful in 18 cases (85.7%). In all 3 failures, the surgeon had difficulty with proper graft placement. Additionally, 2 of these cases were confounded by early inadvertent removal of the lumbar drain. All patients in whom the procedure failed underwent a second successful endoscopic repair. There were no major complications. In our experience endoscopic repair of cerebrospinal fluid rhinorrhea is a safe and effective approach that can be improved with computer-aided localization devices. Proper graft placement is critical, and lumbar drainage is an important adjunct in selected cases. (Otolaryngol Head Neck Surg 2000;122:5660.)
encountered during functional endoscopic sinus surgery (FESS). Immediate recognition and closure of these iatrogenic fistulas was accomplished with mucosal grafts and fibrin glue by Wigand and postauricular fascia and muscle graft by Stankiewicz. Subsequent papers described successful use of endoscopic techniques in patients with active CSF fistulas. In 1989 Papay et al5 reported on 4 successful explorations with repair, and in 1990 Mattox and Kennedy6 reported on 7. Larger series7-11 have since demonstrated initial success rates of 76% to 94%, with ultimate success rates ranging from 86% to 100%. Computer-assisted endoscopic sinus surgery with 3dimensional localization techniques is gaining increasing popularity. Many different systems exist, and a recent comparison of 4 commonly used systems found that all demonstrated relative accuracy and ease of operation.12 We have been using the VTI InstaTrak system for more than 2 years at our institution and find that it is accurate and easy to use. The purpose of this article is to review our institution’s experience with endoscopic repair of CSF fistulas. In addition, we report on the use of a computer-assisted device as an adjunct in the surgical management of CSF rhinorrhea.
T
METHODS AND MATERIAL
he management of cerebrospinal fluid (CSF) rhinorrhea is a complex and challenging problem. When medical management fails, surgical repair had traditionally required intracranial or extracranial approaches with external incisions.1,2 More recently, intranasal repair with endoscopes has been reported with comparable success rates. Wigand3 in 1981 and Stankiewicz4 in 1989 were the first to report on endoscopic repair of CSF rhinorrhea
From the Departments of Otolaryngology–Head and Neck Surgery (Drs Mao, Keane, Atkins, Spiegel, Willcox, Rosen, and Zwillenberg) and Neurosurgery (Dr Andrews), Thomas Jefferson University Hospital. Presented at the Annual Meeting of the American Academy of Otolaryngology–Head Neck Surgery, San Antonio, TX, September 13-16, 1998. Reprint requests: Vivian H. Mao, MD, Department of Otolaryngology–Head and Neck Surgery, 925 Chestnut St, 6th Floor, Philadelphia, PA 19107. Copyright © 2000 by the American Academy of Otolaryngology– Head and Neck Surgery Foundation, Inc. 0194-5998/2000/$12.00 + 0 23/1/98914 56
Charts of all patients who have undergone endoscopic repair of CSF rhinorrhea since 1994 were retrospectively reviewed. Twenty-one cases were identified in 20 patients. There were 13 women and 7 men, with ages ranging from 28 to 71 years (mean 48.0 years). One patient had 2 episodes of iatrogenic CSF rhinorrhea, each encountered during different FESS procedures. The causes of the fistulas were determined to be spontaneous in 10, iatrogenic from FESS in 6, traumatic in 3, and iatrogenic from neurosurgical procedures in 2. In 4 of the 6 FESS-related cases, the CSF leak was encountered intraoperatively and repaired immediately. The other 2 cases were referred from other institutions for subsequent repair. CSF leaks resulting after transsphenoidal hypophysectomy or other neurosurgical procedures were excluded from the study unless the patient had rhinorrhea as a delayed complication. In all, 17 patients underwent primary evaluation and exploration for CSF fistulas. The presenting symptoms of these 17 cases are shown in Table 1. Patients most commonly presented with clear rhinorrhea. Other symptoms included headache, sinus congestion,
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Table 1. Presenting signs and symptoms of 17 patients with CSF fistulas Sign/symptom
No. of patients (%)
Rhinorrhea Headache Sinus congestion Anosmia/hyposmia Meningitis
12 (71) 8 (47) 3 (18) 2 (12) 4 (24)
and hyposmia or anosmia. Four patients had meningitis at presentation. Fine-cut axial and coronal CT scans were obtained in all patients before surgery. Additional radiographic studies were often obtained to help localize the site of defect in patients undergoing exploration and repair. CT cisternography with Omnipaque dye was used in 8, MRI in 3, and radionucleotide (indium 111) cisternography in 6. Findings of each study were later compared with the intraoperative findings to determine the studies’ sensitivity and accuracy. In addition, intraoperative lumbar injection of fluorescein was used in four cases. In 14 patients the VTI InstaTrak system was used for intraoperative localization. These patients underwent an initial CT scan with a headset device in place. The data from this study were transferred to a computer in the operating room. At the time of surgery, the same headset device was replaced on the patient and calibrated with a fiducial marker on the nasal dorsum. The device was also calibrated visually by use of a surgical landmark, such as the middle turbinate, to confirm the accuracy. The locations of the fistulas are shown in Fig 1. Defects in the fovea ethmoidalis were most common, with anterior defects slightly more common than posterior. Other sites of leakage included the cribriform plate, sphenoid sinus, and diaphragma sella. The surgical approach was through a standard FESS technique in 19 cases and through endoscopic transseptal sphenoidotomy in 2. In the former technique, a complete anterior and posterior ethmoidectomy was accomplished with careful preservation of the middle turbinate. The skull base was identified and exposed. When available the InstaTrak localization device was used to confirm the location of the skull base or the actual defect. Sphenoidotomy was performed only in cases where the suspected area of bony dehiscence was in the sphenoid sinus or diaphragma sella. In most cases an extradural repair was accomplished by positioning a free fascial graft through the bony defect into the epidural space as described by previous authors.6,13 In 3 cases of lateral sphenoid sinus defects, epidural placement of fascia was not possible. Repair in these instances was accomplished with fat obliteration of the sinus after complete mucosal strip-
57
Table 2. Sensitivity and accuracy of radiographic studies used in the 17 patients who underwent primary exploration for CSF fistulas
Study
CT sinuses MRI CT cisternogram 111In cisternogram Intraoperative fluorescein
No. of patients
Positive (% sensitivity)
Site
Side
16 3 8 6 4
9 (56) 1 (33) 6 (75) 6 (100) 2 (50)
6 (67) 1 (100) 6 (100) 0 2 (100)
8 (89) 1 (100) 6 (100) 1 (17) 2 (100)
Accuracy (%)
ping. In cases of encephalocele, bipolar electrocautery was first applied to the dural pouch. This technique allowed the dural remnant to retract intracranially, aiding in the optimal placement of a graft. Materials used for repair are shown in Fig 2. Fascial grafts were used most often and included temporalis fascia, fascia lata, and lyophilized dura or fascia. Middle turbinate, septal cartilage or bone, and abdominal fat were used less frequently for primary repair. Whenever technically possible, however, these materials were used for secondary extracranial reinforcement of the primary graft. Thrombogenic agents including Helistat, autologous fibrin glue, Gelfoam, Avitene, and Surgicel were also used to support the graft. All patients had nasal packs placed during surgery, were given parenteral antibiotics in the perioperative period, and were placed on bedrest with the head of the bed elevated after surgery. Lumbar drainage was used in 15 of the 17 patients who underwent exploration and fistula repair. The drain was left in place for 2 to 6 days after surgery (mean 4.0 days) and was clamped to test the stability of the closure before removal. While the drain was in place, CSF specimens were sent daily for fluid count and culture to monitor for meningitis. Spinal fluid drainage was not used in any of the 4 iatrogenic leaks repaired during primary FESS. RESULTS Radiographic Studies
Results of radiographic studies are shown in Table 2. Thin-section CT scans alone were successful in demonstrating a bony defect in 9 of 16 (56.2%) patients who underwent exploration for fistulas, whereas MRI detected areas of dehiscence in only 1 of 3 (33%). Both tests were accurate in determining the actual location of dehiscence. Of the more invasive tests, radionucleotide cisternography was diagnostic in all 6 cases but was not helpful in localizing the defect site, as 5 of these patients demonstrated radionucleotide tracers bilaterally. CT cisternography was positive in 6 of 8 (75%) cases
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Fig 1. Location of CSF fistulas in the 17 patients who underwent primary exploration and repair.
and accurately defined the area of defect in all 6. Intraoperative fluorescein isolated the defect in 2 of 4 (50%) cases. Quantitative results of the InstaTrak device are not available because accurate documentation did not exist in most cases. The authors did find the system to be useful in isolating the fistula site. In every instance where the preoperative CT scan defined a bony defect, the InstaTrak device consistently confirmed the location during surgery. In addition, the system was easy to use, aided in the surgical approach, and contributed to resident teaching. No complications were associated with any of the diagnostic studies. Initial Repairs
Follow-up ranged from 2 to 55 months (mean 18.4 months). Eighteen of 21 (85.7%) initial repairs were successful. There were no major complications. Minor complications included spinal headache in 2 patients, which resolved after removal of the lumbar drain, and postoperative bradycardia in 1 patient, which resolved spontaneously. Initial Failures
The initial repair attempt failed in 3 patients. In all 3 cases, the surgeon had difficulty with proper graft placement because of a relatively inaccessible defect site. The first patient had a bony dehiscence at the cribriform plate anteriorly near the frontoethmoid recess. Placement of a temporalis fascia graft in direct apposition to the skull base was difficult because of the steep angle. The other 2 patients both had defects in the lateral walls of well-pneumatized sphenoid sinuses. Again, because of the difficulty encountered in gaining ready access to the area, a graft could not be placed properly, and the sphenoid sinus was obliterated with fat.
All 3 patients in whom the first repair attempt failed underwent lumbar drainage initially. The first patient’s drain was discontinued on the second postoperative day, at which time she was discharged. In the other 2 cases the drain was prematurely removed and could not be replaced promptly by a neurosurgeon. CSF rhinorrhea was apparent in 1 patient immediately after early inadvertent removal of the lumbar drain. The other 2 patients had symptoms after 20 days and 10 weeks. Second Repairs
All 3 patients had successful closure of their CSF fistulas after the second repair attempt. Lumbar drains were again inserted and left in place for 3 to 5 days (mean 4.3 days). Materials used for the second closure were similar to those used for the first. DISCUSSION
The success rate for initial repair attempts in this series was 18 of 21, or 85.7%, with an ultimate success rate of 100%. Our results compare favorably with those of other published reports. In 1994 Dodson et al7 published the first large series of 29 patients treated with endoscopic techniques. They reported an initial success rate of 75.9% with 1 procedure and 86.2% after a second repair. Four patients in their series required neurosurgical intervention, 3 with craniotomy. These authors used free turbinate or abdominal fat grafts and did not use lumbar drainage. In 1996 Lanza et al10 reviewed their experience with 36 cases and reported an initial success rate of 94.4% and an ultimate success rate of at least 97.2% (1 patient in whom the procedure failed refused further surgery). These authors used mucoperiosteal and mucoperichondrial grafts with postoperative lumbar drainage in most
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Fig 2. Materials used for repair. TF, Temporalis fascia; LD, lyophilized dura or fascia; MT, middle turbinate; FL, fascia lata; F, fat; S, septum. Open bars, Primary repair material; shaded bars, secondary repair material.
patients. They identified the following factors that might predispose to failure: inability to localize the defect, graft displacement, insufficient graft size, incomplete apposition of the graft to the skull base, patient noncompliance, and poor wound healing. In our series the factors that we found most affected outcome were type of graft used, proper graft placement, and adequate lumbar drainage. In all but 3 cases, a fascial or mucoperichondrial/mucoperiosteal graft was used for the initial surgery. The remaining 3 cases were repaired with abdominal fat. Two of these repairs failed initially, suggesting that fat alone may be an inferior graft. Perhaps of more importance in these 3 cases was the inability of the surgeon to place a graft in satisfactory apposition to the skull base within the epidural space. Of the 3 failures, 2 fistulas were sealed with fat only, and the third was repaired with a tenuous temporalis fascia graft. Traditionally lumbar drainage has served as an adjunct for repair. Reports in the neurosurgical literature frequently support the use of spinal drains. In 2 large series of 37 and 42 external repairs, McCormack et al1 and Persky et al2 used spinal drainage in all patients. These authors achieved initial success rates of 86% and overall success rates of 97% and 93%, respectively. Both believed that spinal fluid decompression for at least 72 hours was important. The otolaryngologic literature is less consistent. Dodson et al7 and Hughes et al9 reported final success rates of 86.2% and 94.1%, respectively, using endoscop-
ic techniques without the use of lumbar drainage. Conversely, Lanza et al10 placed spinal drains in 78% of their patients, whereas other authors5,6 used them inconsistently. In our series we used lumbar drainage in 15 of 17 patients who underwent exploration and repair of CSF fistulas. Drains were left in place for 2 to 6 days and clamped before removal to test the closure. In 2 of our 3 failures, the drain was removed prematurely and could not be replaced by a member of the neurosurgical staff. These observations suggest that spinal fluid decompression may be helpful, especially in cases where the repair is tenuous. In such instances lumbar drainage is appropriate and should remain in place for a minimum of 3 days with clamping before removal. Radiographic studies can be valuable in determining the location of the skull base defect. In our series, radionucleotide cisternography was the most sensitive (100%) test but could not accurately identify the site in any patient. CT cisternography was most accurate in localizing the area of defect but was less sensitive (67%). Thin-section CT alone defined the area of leakage in just more than half of cases. Because all patients require this study before surgery, we believe that CT scan should serve as the principal study, with more invasive tests reserved for cases in which no defect is detected. Computer-aided endoscopic sinus surgery is currently being used with increasing frequency. In 1998 Anon12 reviewed 4 different 3-dimensional localization techniques. He measured the accuracy of the ISG viewing
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wand and the ISG infrared OptoTrak on patients undergoing routine FESS and found the mean accuracy to be 1.8 mm and 1.88 mm, respectively. He then used laboratory specimens to determine the accuracy of the IGT FlashPoint 500 and the VTI InstaTrak systems, which he reported to be 0.843 mm and 0.35 mm, respectively. We used the VTI InstaTrak in most patients in this series. In every case where defects were identified on preoperative CT scans, the InstaTrak device confirmed the site of defect. CONCLUSIONS
We believe that endoscopic repair is a safe and effective technique for closure of CSF rhinorrhea. Even after initial failure the success rate of repeat endoscopic repair is high. The most important factor in successful closure is proper graft placement in the epidural space. Lumbar drainage remains controversial but should be used in cases where the repair is believed to be tenuous. CT scanning serves as the principal imaging study, with more invasive tests reserved for cases where bony defects are not detected. In addition, computer-aided techniques are valuable in assisting with exposure and detection of the defect site. Addendum: After this report was submitted for publication, 1 patient who had undergone a second endoscopic repair attempt had a recurrence of her symptoms. She had an encephalocele that penetrated into a relatively inaccessible lateral sphenoid sinus recess. Persistence of a CSF fistula was documented by CT cisternography. A craniotomy and repair
with hydroxyapatite were subsequently performed and failed. She is currently awaiting a third endoscopic approach. REFERENCES 1. McCormack B, Cooper PR, Persky M, et al. Extracranial repair of cerebrospinal fluid fistulas: technique and results in 37 patients. Neurosurgery 1990;27:412-7. 2. Persky MS, Rothstein SG, Breda SD, et al. Extracranial repair of cerebrospinal fluid otorhinorrhea. Laryngoscope 1991;101:134-6. 3. Wigand ME. Transnasal ethmoidectomy under endoscopic control. Rhinology 1981;19:7-15. 4. Stankiewicz JA. Complications in endoscopic intranasal ethmoidectomy: an update. Laryngoscope 1989;99:686-90. 5. Papay FA, Maggiano H, Dominquez S, et al. Rigid endoscopic repair of paranasal sinus cerebrospinal fluid fistulas. Laryngoscope 1989;99:1195-201. 6. Mattox DE, Kennedy DW. Endoscopic management of cerebrospinal fluid leaks and cephaloceles. Laryngoscope 1996;100: 1119-25. 7. Dodson EE, Gross CW, Swerdloff JL, et al. Transnasal endoscopic repair of cerebrospinal fluid rhinorrhea and skull base defects: a review of twenty-nine cases. Otolaryngol Head Neck Surg 1994;111:600-5. 8. Gjuric M, Goede U, Keimer H, et al. Endonasal endoscopic closure of cerebrospinal fluid fistulas at the anterior cranial base. Ann Otol Rhinol Laryngol 1996;105:620-3. 9. Hughes RGM, Jones NS, Robertson IJA. The endoscopic treatment of cerebrospinal fluid rhinorrhoea: the Nottingham experience. J Laryngol Otol 1997;111:125-8. 10. Lanza DC, O’Brien DA, Kennedy DW. Endoscopic management of cerebrospinal fluid fistulae and encephaloceles. Laryngoscope 1996;106:1119-25. 11. Wax MK, Ramadan HH, Ortiz O, et al. Contemporary management of cerebrospinal fluid rhinorrhea. Otolaryngol Head Neck Surg 1997;116:442-9. 12. Anon JB. Computer-aided endoscopic sinus surgery. Laryngoscope 1998;108:949-61. 13. Hao SP. Transnasal endoscopic repair of cerebrospinal fluid rhinorrhea: an interposition technique. Laryngoscope 1996;108: 501-3.
International Conference on Newborn Hearing Screening Diagnosis and Intervention
The conference will be held October 12-14, 2000, in Milan, Italy. Abstracts must be received by May 15, 2000. For further information Contact Dr Deborah Hayes at 303-861-6800 or Dr Ferdinando Grandori at [email protected].
Endoscopic repair of cerebrospinal fluid rhinorrhea is a promising alternative to traditional repair techniques. This article reports our experience with 21 cases (10 spontaneous, 8 iatrogenic, and 3 traumatic). Various diagnostic radiographic modalities were used, including computer-aided techniques. Most repairs were accomplished with a free fascial graft positioned in the epidural space. Postoperative lumbar drainage was used in 15 cases. Initial repair was successful in 18 cases (85.7%). In all 3 failures, the surgeon had difficulty with proper graft placement. Additionally, 2 of these cases were confounded by early inadvertent removal of the lumbar drain. All patients in whom the procedure failed underwent a second successful endoscopic repair. There were no major complications. In our experience endoscopic repair of cerebrospinal fluid rhinorrhea is a safe and effective approach that can be improved with computer-aided localization devices. Proper graft placement is critical, and lumbar drainage is an important adjunct in selected cases. (Otolaryngol Head Neck Surg 2000;122:5660.)
encountered during functional endoscopic sinus surgery (FESS). Immediate recognition and closure of these iatrogenic fistulas was accomplished with mucosal grafts and fibrin glue by Wigand and postauricular fascia and muscle graft by Stankiewicz. Subsequent papers described successful use of endoscopic techniques in patients with active CSF fistulas. In 1989 Papay et al5 reported on 4 successful explorations with repair, and in 1990 Mattox and Kennedy6 reported on 7. Larger series7-11 have since demonstrated initial success rates of 76% to 94%, with ultimate success rates ranging from 86% to 100%. Computer-assisted endoscopic sinus surgery with 3dimensional localization techniques is gaining increasing popularity. Many different systems exist, and a recent comparison of 4 commonly used systems found that all demonstrated relative accuracy and ease of operation.12 We have been using the VTI InstaTrak system for more than 2 years at our institution and find that it is accurate and easy to use. The purpose of this article is to review our institution’s experience with endoscopic repair of CSF fistulas. In addition, we report on the use of a computer-assisted device as an adjunct in the surgical management of CSF rhinorrhea.
T
METHODS AND MATERIAL
he management of cerebrospinal fluid (CSF) rhinorrhea is a complex and challenging problem. When medical management fails, surgical repair had traditionally required intracranial or extracranial approaches with external incisions.1,2 More recently, intranasal repair with endoscopes has been reported with comparable success rates. Wigand3 in 1981 and Stankiewicz4 in 1989 were the first to report on endoscopic repair of CSF rhinorrhea
From the Departments of Otolaryngology–Head and Neck Surgery (Drs Mao, Keane, Atkins, Spiegel, Willcox, Rosen, and Zwillenberg) and Neurosurgery (Dr Andrews), Thomas Jefferson University Hospital. Presented at the Annual Meeting of the American Academy of Otolaryngology–Head Neck Surgery, San Antonio, TX, September 13-16, 1998. Reprint requests: Vivian H. Mao, MD, Department of Otolaryngology–Head and Neck Surgery, 925 Chestnut St, 6th Floor, Philadelphia, PA 19107. Copyright © 2000 by the American Academy of Otolaryngology– Head and Neck Surgery Foundation, Inc. 0194-5998/2000/$12.00 + 0 23/1/98914 56
Charts of all patients who have undergone endoscopic repair of CSF rhinorrhea since 1994 were retrospectively reviewed. Twenty-one cases were identified in 20 patients. There were 13 women and 7 men, with ages ranging from 28 to 71 years (mean 48.0 years). One patient had 2 episodes of iatrogenic CSF rhinorrhea, each encountered during different FESS procedures. The causes of the fistulas were determined to be spontaneous in 10, iatrogenic from FESS in 6, traumatic in 3, and iatrogenic from neurosurgical procedures in 2. In 4 of the 6 FESS-related cases, the CSF leak was encountered intraoperatively and repaired immediately. The other 2 cases were referred from other institutions for subsequent repair. CSF leaks resulting after transsphenoidal hypophysectomy or other neurosurgical procedures were excluded from the study unless the patient had rhinorrhea as a delayed complication. In all, 17 patients underwent primary evaluation and exploration for CSF fistulas. The presenting symptoms of these 17 cases are shown in Table 1. Patients most commonly presented with clear rhinorrhea. Other symptoms included headache, sinus congestion,
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Table 1. Presenting signs and symptoms of 17 patients with CSF fistulas Sign/symptom
No. of patients (%)
Rhinorrhea Headache Sinus congestion Anosmia/hyposmia Meningitis
12 (71) 8 (47) 3 (18) 2 (12) 4 (24)
and hyposmia or anosmia. Four patients had meningitis at presentation. Fine-cut axial and coronal CT scans were obtained in all patients before surgery. Additional radiographic studies were often obtained to help localize the site of defect in patients undergoing exploration and repair. CT cisternography with Omnipaque dye was used in 8, MRI in 3, and radionucleotide (indium 111) cisternography in 6. Findings of each study were later compared with the intraoperative findings to determine the studies’ sensitivity and accuracy. In addition, intraoperative lumbar injection of fluorescein was used in four cases. In 14 patients the VTI InstaTrak system was used for intraoperative localization. These patients underwent an initial CT scan with a headset device in place. The data from this study were transferred to a computer in the operating room. At the time of surgery, the same headset device was replaced on the patient and calibrated with a fiducial marker on the nasal dorsum. The device was also calibrated visually by use of a surgical landmark, such as the middle turbinate, to confirm the accuracy. The locations of the fistulas are shown in Fig 1. Defects in the fovea ethmoidalis were most common, with anterior defects slightly more common than posterior. Other sites of leakage included the cribriform plate, sphenoid sinus, and diaphragma sella. The surgical approach was through a standard FESS technique in 19 cases and through endoscopic transseptal sphenoidotomy in 2. In the former technique, a complete anterior and posterior ethmoidectomy was accomplished with careful preservation of the middle turbinate. The skull base was identified and exposed. When available the InstaTrak localization device was used to confirm the location of the skull base or the actual defect. Sphenoidotomy was performed only in cases where the suspected area of bony dehiscence was in the sphenoid sinus or diaphragma sella. In most cases an extradural repair was accomplished by positioning a free fascial graft through the bony defect into the epidural space as described by previous authors.6,13 In 3 cases of lateral sphenoid sinus defects, epidural placement of fascia was not possible. Repair in these instances was accomplished with fat obliteration of the sinus after complete mucosal strip-
57
Table 2. Sensitivity and accuracy of radiographic studies used in the 17 patients who underwent primary exploration for CSF fistulas
Study
CT sinuses MRI CT cisternogram 111In cisternogram Intraoperative fluorescein
No. of patients
Positive (% sensitivity)
Site
Side
16 3 8 6 4
9 (56) 1 (33) 6 (75) 6 (100) 2 (50)
6 (67) 1 (100) 6 (100) 0 2 (100)
8 (89) 1 (100) 6 (100) 1 (17) 2 (100)
Accuracy (%)
ping. In cases of encephalocele, bipolar electrocautery was first applied to the dural pouch. This technique allowed the dural remnant to retract intracranially, aiding in the optimal placement of a graft. Materials used for repair are shown in Fig 2. Fascial grafts were used most often and included temporalis fascia, fascia lata, and lyophilized dura or fascia. Middle turbinate, septal cartilage or bone, and abdominal fat were used less frequently for primary repair. Whenever technically possible, however, these materials were used for secondary extracranial reinforcement of the primary graft. Thrombogenic agents including Helistat, autologous fibrin glue, Gelfoam, Avitene, and Surgicel were also used to support the graft. All patients had nasal packs placed during surgery, were given parenteral antibiotics in the perioperative period, and were placed on bedrest with the head of the bed elevated after surgery. Lumbar drainage was used in 15 of the 17 patients who underwent exploration and fistula repair. The drain was left in place for 2 to 6 days after surgery (mean 4.0 days) and was clamped to test the stability of the closure before removal. While the drain was in place, CSF specimens were sent daily for fluid count and culture to monitor for meningitis. Spinal fluid drainage was not used in any of the 4 iatrogenic leaks repaired during primary FESS. RESULTS Radiographic Studies
Results of radiographic studies are shown in Table 2. Thin-section CT scans alone were successful in demonstrating a bony defect in 9 of 16 (56.2%) patients who underwent exploration for fistulas, whereas MRI detected areas of dehiscence in only 1 of 3 (33%). Both tests were accurate in determining the actual location of dehiscence. Of the more invasive tests, radionucleotide cisternography was diagnostic in all 6 cases but was not helpful in localizing the defect site, as 5 of these patients demonstrated radionucleotide tracers bilaterally. CT cisternography was positive in 6 of 8 (75%) cases
58
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Fig 1. Location of CSF fistulas in the 17 patients who underwent primary exploration and repair.
and accurately defined the area of defect in all 6. Intraoperative fluorescein isolated the defect in 2 of 4 (50%) cases. Quantitative results of the InstaTrak device are not available because accurate documentation did not exist in most cases. The authors did find the system to be useful in isolating the fistula site. In every instance where the preoperative CT scan defined a bony defect, the InstaTrak device consistently confirmed the location during surgery. In addition, the system was easy to use, aided in the surgical approach, and contributed to resident teaching. No complications were associated with any of the diagnostic studies. Initial Repairs
Follow-up ranged from 2 to 55 months (mean 18.4 months). Eighteen of 21 (85.7%) initial repairs were successful. There were no major complications. Minor complications included spinal headache in 2 patients, which resolved after removal of the lumbar drain, and postoperative bradycardia in 1 patient, which resolved spontaneously. Initial Failures
The initial repair attempt failed in 3 patients. In all 3 cases, the surgeon had difficulty with proper graft placement because of a relatively inaccessible defect site. The first patient had a bony dehiscence at the cribriform plate anteriorly near the frontoethmoid recess. Placement of a temporalis fascia graft in direct apposition to the skull base was difficult because of the steep angle. The other 2 patients both had defects in the lateral walls of well-pneumatized sphenoid sinuses. Again, because of the difficulty encountered in gaining ready access to the area, a graft could not be placed properly, and the sphenoid sinus was obliterated with fat.
All 3 patients in whom the first repair attempt failed underwent lumbar drainage initially. The first patient’s drain was discontinued on the second postoperative day, at which time she was discharged. In the other 2 cases the drain was prematurely removed and could not be replaced promptly by a neurosurgeon. CSF rhinorrhea was apparent in 1 patient immediately after early inadvertent removal of the lumbar drain. The other 2 patients had symptoms after 20 days and 10 weeks. Second Repairs
All 3 patients had successful closure of their CSF fistulas after the second repair attempt. Lumbar drains were again inserted and left in place for 3 to 5 days (mean 4.3 days). Materials used for the second closure were similar to those used for the first. DISCUSSION
The success rate for initial repair attempts in this series was 18 of 21, or 85.7%, with an ultimate success rate of 100%. Our results compare favorably with those of other published reports. In 1994 Dodson et al7 published the first large series of 29 patients treated with endoscopic techniques. They reported an initial success rate of 75.9% with 1 procedure and 86.2% after a second repair. Four patients in their series required neurosurgical intervention, 3 with craniotomy. These authors used free turbinate or abdominal fat grafts and did not use lumbar drainage. In 1996 Lanza et al10 reviewed their experience with 36 cases and reported an initial success rate of 94.4% and an ultimate success rate of at least 97.2% (1 patient in whom the procedure failed refused further surgery). These authors used mucoperiosteal and mucoperichondrial grafts with postoperative lumbar drainage in most
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Fig 2. Materials used for repair. TF, Temporalis fascia; LD, lyophilized dura or fascia; MT, middle turbinate; FL, fascia lata; F, fat; S, septum. Open bars, Primary repair material; shaded bars, secondary repair material.
patients. They identified the following factors that might predispose to failure: inability to localize the defect, graft displacement, insufficient graft size, incomplete apposition of the graft to the skull base, patient noncompliance, and poor wound healing. In our series the factors that we found most affected outcome were type of graft used, proper graft placement, and adequate lumbar drainage. In all but 3 cases, a fascial or mucoperichondrial/mucoperiosteal graft was used for the initial surgery. The remaining 3 cases were repaired with abdominal fat. Two of these repairs failed initially, suggesting that fat alone may be an inferior graft. Perhaps of more importance in these 3 cases was the inability of the surgeon to place a graft in satisfactory apposition to the skull base within the epidural space. Of the 3 failures, 2 fistulas were sealed with fat only, and the third was repaired with a tenuous temporalis fascia graft. Traditionally lumbar drainage has served as an adjunct for repair. Reports in the neurosurgical literature frequently support the use of spinal drains. In 2 large series of 37 and 42 external repairs, McCormack et al1 and Persky et al2 used spinal drainage in all patients. These authors achieved initial success rates of 86% and overall success rates of 97% and 93%, respectively. Both believed that spinal fluid decompression for at least 72 hours was important. The otolaryngologic literature is less consistent. Dodson et al7 and Hughes et al9 reported final success rates of 86.2% and 94.1%, respectively, using endoscop-
ic techniques without the use of lumbar drainage. Conversely, Lanza et al10 placed spinal drains in 78% of their patients, whereas other authors5,6 used them inconsistently. In our series we used lumbar drainage in 15 of 17 patients who underwent exploration and repair of CSF fistulas. Drains were left in place for 2 to 6 days and clamped before removal to test the closure. In 2 of our 3 failures, the drain was removed prematurely and could not be replaced by a member of the neurosurgical staff. These observations suggest that spinal fluid decompression may be helpful, especially in cases where the repair is tenuous. In such instances lumbar drainage is appropriate and should remain in place for a minimum of 3 days with clamping before removal. Radiographic studies can be valuable in determining the location of the skull base defect. In our series, radionucleotide cisternography was the most sensitive (100%) test but could not accurately identify the site in any patient. CT cisternography was most accurate in localizing the area of defect but was less sensitive (67%). Thin-section CT alone defined the area of leakage in just more than half of cases. Because all patients require this study before surgery, we believe that CT scan should serve as the principal study, with more invasive tests reserved for cases in which no defect is detected. Computer-aided endoscopic sinus surgery is currently being used with increasing frequency. In 1998 Anon12 reviewed 4 different 3-dimensional localization techniques. He measured the accuracy of the ISG viewing
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MAO et al
wand and the ISG infrared OptoTrak on patients undergoing routine FESS and found the mean accuracy to be 1.8 mm and 1.88 mm, respectively. He then used laboratory specimens to determine the accuracy of the IGT FlashPoint 500 and the VTI InstaTrak systems, which he reported to be 0.843 mm and 0.35 mm, respectively. We used the VTI InstaTrak in most patients in this series. In every case where defects were identified on preoperative CT scans, the InstaTrak device confirmed the site of defect. CONCLUSIONS
We believe that endoscopic repair is a safe and effective technique for closure of CSF rhinorrhea. Even after initial failure the success rate of repeat endoscopic repair is high. The most important factor in successful closure is proper graft placement in the epidural space. Lumbar drainage remains controversial but should be used in cases where the repair is believed to be tenuous. CT scanning serves as the principal imaging study, with more invasive tests reserved for cases where bony defects are not detected. In addition, computer-aided techniques are valuable in assisting with exposure and detection of the defect site. Addendum: After this report was submitted for publication, 1 patient who had undergone a second endoscopic repair attempt had a recurrence of her symptoms. She had an encephalocele that penetrated into a relatively inaccessible lateral sphenoid sinus recess. Persistence of a CSF fistula was documented by CT cisternography. A craniotomy and repair
with hydroxyapatite were subsequently performed and failed. She is currently awaiting a third endoscopic approach. REFERENCES 1. McCormack B, Cooper PR, Persky M, et al. Extracranial repair of cerebrospinal fluid fistulas: technique and results in 37 patients. Neurosurgery 1990;27:412-7. 2. Persky MS, Rothstein SG, Breda SD, et al. Extracranial repair of cerebrospinal fluid otorhinorrhea. Laryngoscope 1991;101:134-6. 3. Wigand ME. Transnasal ethmoidectomy under endoscopic control. Rhinology 1981;19:7-15. 4. Stankiewicz JA. Complications in endoscopic intranasal ethmoidectomy: an update. Laryngoscope 1989;99:686-90. 5. Papay FA, Maggiano H, Dominquez S, et al. Rigid endoscopic repair of paranasal sinus cerebrospinal fluid fistulas. Laryngoscope 1989;99:1195-201. 6. Mattox DE, Kennedy DW. Endoscopic management of cerebrospinal fluid leaks and cephaloceles. Laryngoscope 1996;100: 1119-25. 7. Dodson EE, Gross CW, Swerdloff JL, et al. Transnasal endoscopic repair of cerebrospinal fluid rhinorrhea and skull base defects: a review of twenty-nine cases. Otolaryngol Head Neck Surg 1994;111:600-5. 8. Gjuric M, Goede U, Keimer H, et al. Endonasal endoscopic closure of cerebrospinal fluid fistulas at the anterior cranial base. Ann Otol Rhinol Laryngol 1996;105:620-3. 9. Hughes RGM, Jones NS, Robertson IJA. The endoscopic treatment of cerebrospinal fluid rhinorrhoea: the Nottingham experience. J Laryngol Otol 1997;111:125-8. 10. Lanza DC, O’Brien DA, Kennedy DW. Endoscopic management of cerebrospinal fluid fistulae and encephaloceles. Laryngoscope 1996;106:1119-25. 11. Wax MK, Ramadan HH, Ortiz O, et al. Contemporary management of cerebrospinal fluid rhinorrhea. Otolaryngol Head Neck Surg 1997;116:442-9. 12. Anon JB. Computer-aided endoscopic sinus surgery. Laryngoscope 1998;108:949-61. 13. Hao SP. Transnasal endoscopic repair of cerebrospinal fluid rhinorrhea: an interposition technique. Laryngoscope 1996;108: 501-3.
International Conference on Newborn Hearing Screening Diagnosis and Intervention
The conference will be held October 12-14, 2000, in Milan, Italy. Abstracts must be received by May 15, 2000. For further information Contact Dr Deborah Hayes at 303-861-6800 or Dr Ferdinando Grandori at [email protected].