ORIGINAL ARTICLE
Immediate postoperative imaging aer uncomplicated endoscopic approach to the anterior skull base: is it necessary? Sahar Nadimi, MD1 , Nadieska Caballero, MD1 , Patrick Carpenter, MS2 , Lauren Sowa, MS2 , Ryan Cunningham, MS2 and Kevin C. Welch, MD, FACS1
Background: Postoperative imaging is frequently performed to assess for intracranial complications following anterior skull base (ASB) surgery. However, there is lile data to suggest that radiologic studies change the management of complications. In this study, the utility of postoperative imaging within 72 hours aer uncomplicated ASB surgery was examined. Methods: A retrospective review was conducted of 143 patients who underwent endoscopic ASB surgery between 2007 and 2013 at Loyola University Medical Center. The main outcomes measures included the ability of head computed tomography (CT) scan to identify postoperative complications and hallmark symptoms associated with complications. Results: Seventy-nine patients underwent postoperative imaging within 72 hours of the initial surgery. The most common finding was pneumocephalus (35/79; 44%). Expanding pneumocephalus requiring surgical intervention developed in 3 cases. Cerebrospinal fluid (CSF) leak was the most common complication, occurring in 22 of 143 (15%) of the patients. Of the 24 patients who developed a postoperative
E
ndoscopic anterior skull base (ASB) surgery allows for the treatment of a multitude of benign and malignant neoplastic pathologies.1 Although the approaches vary, the goals of endoscopic ASB surgery include: (1) tumor resection; (2) preservation of neurologic function; (3) preservation of sinonasal respiratory function;
1 Department
of Otolaryngology, Loyola University Chicago Stritch School of Medicine, Maywood, IL; 2 Loyola University Chicago Stritch School of Medicine, Maywood, IL
Correspondence to: Kevin C. Welch, MD, FACS, Department of Otolaryngology–Head and Neck Surgery, 2160 S. First Ave., Maywood, IL 60153; e-mail: [email protected] Potential conflict of interest: None provided. Received: 15 April 2014; Revised: 21 June 2014; Accepted: 18 July 2014 DOI: 10.1002/alr.21405 View this article online at wileyonlinelibrary.com.
complication, all had clinical signs or symptoms indicative of the need for surgical or medical intervention. The positive predictive value for a head CT scan to detect a complication was 12%, negative predictive value was 92%, and sensitivity and specificity were 63% and 48%, respectively. Conclusion: Routine postoperative imaging may be unnecessary aer uncomplicated endoscopic ASB surgery because (1) it may not alter patient management; (2) it may not detect the most common complication (CSF leak); and (3) when imaging is positive, the patient has clinical symptoms C 2014 ARS-AAOA, LLC. suggesting a need for intervention.
Key Words: anterior skull base; computed tomography; CSF rhinorrhea; endoscopic skull-base surgery; imaging; postoperative How to Cite this Article: Nadimi S, Caballero N, Carpenter P, et al. Immediate postoperative imaging aer uncomplicated endoscopic approach to the anterior skull base: is it necessary? Int Forum Allergy Rhinol. 2014;4:1024–1029.
(4) reduction of operative complications; and (5) improved aesthetic outcome.2, 3 Advances in instrumentation, surgical navigation, and skull-base reconstruction have allowed for endoscopic skull-base surgery to emerge as a less invasive alternative to open approaches for select ASB lesions.3 The purely endoscopic approaches preclude the need for craniotomy and brain retraction, which are a source of morbidity while using open techniques. Additional advantages are shorter duration of surgery, decreased hospital stay, decreased blood loss and transfusion rate, faster recovery, and improved aesthetic outcome.1, 4 Equally important, some studies find no significant differences in survival, recurrence, metastases, or complication rates when comparing endoscopic to open approaches for malignant ASB tumors.1, 5, 6 Endoscopic resection of ASB tumors may result in large defects that create a connection between the intracranial
International Forum of Allergy & Rhinology, Vol. 4, No. 12, December 2014
1024
Endoscopic ASB surgery: postoperative imaging
and sinonasal cavities, forming a potential source for cerebrospinal fluid (CSF) leak, postoperative meningitis, and intracranial abscess.1 Prior studies have demonstrated that the most common complication after endoscopic endonasal cranial base resections is CSF leak, occurring in 16% of patients.2 Additional complications included intracranial infections (1.9%), vascular injury (0.9%), and neurologic deficits (1.8%).2 The adoption of the nasoseptal flap for skull-base reconstruction contributed to a significant decrease in the rate of postoperative CSF leak. Reconstruction failures may also result in pneumocephalus. Opening of the cranial vault invariably results in the trapping of a small amount of air. In rare cases, however, this volume may expand postoperatively, potentially in combination with a CSF leak. Significant gas volumes may lead to tension pneumocephalus, in which intracranial structures are compressed, blood flow is inhibited, and herniation is possible. Tension pneumocephalus is an extremely rare complication of endoscopic skull-base surgery.7 Postoperative imaging is frequently performed to assess for intracranial complications following ASB surgery, even in the absence of any neurologic deficits. Several authors favor routine computed tomography (CT) or magnetic resonance imaging (MRI) of the brain within the first 24 hours after surgery to exclude evidence of intracranial bleeding, parenchymal injury, or tension pneumocephalus.7–10 This practice is widespread despite the fact that the most common complication following endoscopic skull-base surgery is CSF rhinorrhea. For many, CSF rhinorrhea is typically a clinical diagnosis and imaging may be obtained when the precise location of the leak is uncertain. Thus, in this study, we attempted to examine the utility of postoperative imaging within 72 hours after uncomplicated ASB surgery as it relates to identification of postoperative complications. In addition, we aimed to identify whether imaging results had any effect on subsequent patient management.
Patients and methods A retrospective chart review was performed of patients who underwent endoscopic ASB surgery by the same senior surgeon (K.C.W.) between 2007 and 2013 at Loyola University Medical Center. Charts were reviewed for the following data: age, sex, body mass index, preoperative signs and symptoms, type of approach to the ASB, pathology, postoperative signs and symptoms, complications, postoperative imaging (findings and timing of study), and outcomes. All patients included required surgery that included the skull base, either intradural, extradural, or both. Endoscopic approaches to the ASB included in this study were defined as transcribriform, transsellar/transpituitary, transpterygoid, transfrontal, transclival, transplanum, and/or extended sinonasal surgery along the skull base. Patients who underwent a combined open and endoscopic approach were excluded. Outcomes measured included postoperative complications, clinical symptoms
1025
TABLE 1. Surgical approaches to the anterior skull base Approach
n (%)
Transpituitary/transsellar
64 (45)
Extended sinonasal resection
32 (22)
Transcribriform
17 (12)
Transpterygoid
12 (8)
Transplanum
4 (3)
Transclival
5 (4)
Transfrontal
6 (4)
Other
3 (2)
associated with the complications, and the ability of CT of the head to detect postoperative complications. Additionally, the relationship between surgical approaches and the development of complications was examined. The study was approved by the Loyola University Medical Center Institutional Review Board.
Statistical analysis To examine the association between the categorical variables (surgical approaches) and the postoperative complications, a Fisher’s exact test was used. A p value of
Immediate postoperative imaging aer uncomplicated endoscopic approach to the anterior skull base: is it necessary? Sahar Nadimi, MD1 , Nadieska Caballero, MD1 , Patrick Carpenter, MS2 , Lauren Sowa, MS2 , Ryan Cunningham, MS2 and Kevin C. Welch, MD, FACS1
Background: Postoperative imaging is frequently performed to assess for intracranial complications following anterior skull base (ASB) surgery. However, there is lile data to suggest that radiologic studies change the management of complications. In this study, the utility of postoperative imaging within 72 hours aer uncomplicated ASB surgery was examined. Methods: A retrospective review was conducted of 143 patients who underwent endoscopic ASB surgery between 2007 and 2013 at Loyola University Medical Center. The main outcomes measures included the ability of head computed tomography (CT) scan to identify postoperative complications and hallmark symptoms associated with complications. Results: Seventy-nine patients underwent postoperative imaging within 72 hours of the initial surgery. The most common finding was pneumocephalus (35/79; 44%). Expanding pneumocephalus requiring surgical intervention developed in 3 cases. Cerebrospinal fluid (CSF) leak was the most common complication, occurring in 22 of 143 (15%) of the patients. Of the 24 patients who developed a postoperative
E
ndoscopic anterior skull base (ASB) surgery allows for the treatment of a multitude of benign and malignant neoplastic pathologies.1 Although the approaches vary, the goals of endoscopic ASB surgery include: (1) tumor resection; (2) preservation of neurologic function; (3) preservation of sinonasal respiratory function;
1 Department
of Otolaryngology, Loyola University Chicago Stritch School of Medicine, Maywood, IL; 2 Loyola University Chicago Stritch School of Medicine, Maywood, IL
Correspondence to: Kevin C. Welch, MD, FACS, Department of Otolaryngology–Head and Neck Surgery, 2160 S. First Ave., Maywood, IL 60153; e-mail: [email protected] Potential conflict of interest: None provided. Received: 15 April 2014; Revised: 21 June 2014; Accepted: 18 July 2014 DOI: 10.1002/alr.21405 View this article online at wileyonlinelibrary.com.
complication, all had clinical signs or symptoms indicative of the need for surgical or medical intervention. The positive predictive value for a head CT scan to detect a complication was 12%, negative predictive value was 92%, and sensitivity and specificity were 63% and 48%, respectively. Conclusion: Routine postoperative imaging may be unnecessary aer uncomplicated endoscopic ASB surgery because (1) it may not alter patient management; (2) it may not detect the most common complication (CSF leak); and (3) when imaging is positive, the patient has clinical symptoms C 2014 ARS-AAOA, LLC. suggesting a need for intervention.
Key Words: anterior skull base; computed tomography; CSF rhinorrhea; endoscopic skull-base surgery; imaging; postoperative How to Cite this Article: Nadimi S, Caballero N, Carpenter P, et al. Immediate postoperative imaging aer uncomplicated endoscopic approach to the anterior skull base: is it necessary? Int Forum Allergy Rhinol. 2014;4:1024–1029.
(4) reduction of operative complications; and (5) improved aesthetic outcome.2, 3 Advances in instrumentation, surgical navigation, and skull-base reconstruction have allowed for endoscopic skull-base surgery to emerge as a less invasive alternative to open approaches for select ASB lesions.3 The purely endoscopic approaches preclude the need for craniotomy and brain retraction, which are a source of morbidity while using open techniques. Additional advantages are shorter duration of surgery, decreased hospital stay, decreased blood loss and transfusion rate, faster recovery, and improved aesthetic outcome.1, 4 Equally important, some studies find no significant differences in survival, recurrence, metastases, or complication rates when comparing endoscopic to open approaches for malignant ASB tumors.1, 5, 6 Endoscopic resection of ASB tumors may result in large defects that create a connection between the intracranial
International Forum of Allergy & Rhinology, Vol. 4, No. 12, December 2014
1024
Endoscopic ASB surgery: postoperative imaging
and sinonasal cavities, forming a potential source for cerebrospinal fluid (CSF) leak, postoperative meningitis, and intracranial abscess.1 Prior studies have demonstrated that the most common complication after endoscopic endonasal cranial base resections is CSF leak, occurring in 16% of patients.2 Additional complications included intracranial infections (1.9%), vascular injury (0.9%), and neurologic deficits (1.8%).2 The adoption of the nasoseptal flap for skull-base reconstruction contributed to a significant decrease in the rate of postoperative CSF leak. Reconstruction failures may also result in pneumocephalus. Opening of the cranial vault invariably results in the trapping of a small amount of air. In rare cases, however, this volume may expand postoperatively, potentially in combination with a CSF leak. Significant gas volumes may lead to tension pneumocephalus, in which intracranial structures are compressed, blood flow is inhibited, and herniation is possible. Tension pneumocephalus is an extremely rare complication of endoscopic skull-base surgery.7 Postoperative imaging is frequently performed to assess for intracranial complications following ASB surgery, even in the absence of any neurologic deficits. Several authors favor routine computed tomography (CT) or magnetic resonance imaging (MRI) of the brain within the first 24 hours after surgery to exclude evidence of intracranial bleeding, parenchymal injury, or tension pneumocephalus.7–10 This practice is widespread despite the fact that the most common complication following endoscopic skull-base surgery is CSF rhinorrhea. For many, CSF rhinorrhea is typically a clinical diagnosis and imaging may be obtained when the precise location of the leak is uncertain. Thus, in this study, we attempted to examine the utility of postoperative imaging within 72 hours after uncomplicated ASB surgery as it relates to identification of postoperative complications. In addition, we aimed to identify whether imaging results had any effect on subsequent patient management.
Patients and methods A retrospective chart review was performed of patients who underwent endoscopic ASB surgery by the same senior surgeon (K.C.W.) between 2007 and 2013 at Loyola University Medical Center. Charts were reviewed for the following data: age, sex, body mass index, preoperative signs and symptoms, type of approach to the ASB, pathology, postoperative signs and symptoms, complications, postoperative imaging (findings and timing of study), and outcomes. All patients included required surgery that included the skull base, either intradural, extradural, or both. Endoscopic approaches to the ASB included in this study were defined as transcribriform, transsellar/transpituitary, transpterygoid, transfrontal, transclival, transplanum, and/or extended sinonasal surgery along the skull base. Patients who underwent a combined open and endoscopic approach were excluded. Outcomes measured included postoperative complications, clinical symptoms
1025
TABLE 1. Surgical approaches to the anterior skull base Approach
n (%)
Transpituitary/transsellar
64 (45)
Extended sinonasal resection
32 (22)
Transcribriform
17 (12)
Transpterygoid
12 (8)
Transplanum
4 (3)
Transclival
5 (4)
Transfrontal
6 (4)
Other
3 (2)
associated with the complications, and the ability of CT of the head to detect postoperative complications. Additionally, the relationship between surgical approaches and the development of complications was examined. The study was approved by the Loyola University Medical Center Institutional Review Board.
Statistical analysis To examine the association between the categorical variables (surgical approaches) and the postoperative complications, a Fisher’s exact test was used. A p value of
