✓Craniopharyngiomas have always been an extremely challenging type of tumor to treat. The transsphenoidal route has been used for resection of these lesions since its introduction. The authors present a historical review of the literature from the introduction of the endonasal route for resection of craniopharyngiomas until the present. Abandoned early due to technological limitations, this approach has been expanded both in its application and in its anatomical boundaries with subsequent progressive improvements in outcomes. This expansion has coincided with advances in visualization devices, imaging guidance techniques, and anatomical understanding. The progression from the use of headlights, to microscopy, to endoscopy and fluoroscopy, and finally to modern intraoperative magnetic resonance–guided techniques, combined with collaboration between otolaryngologists and neurosurgeons, has provided the framework for the development of current techniques for the resection of sellar and suprasellar craniopharyngiomas.
Paul A. Gardner, Daniel M. Prevedello, Amin B. Kassam, Carl H. Snyderman, Ricardo L. Carrau and Arlan H. Mintz
Edward E. Kerr, Daniel M. Prevedello, Ali Jamshidi, Leo F. Ditzel Filho, Bradley A. Otto and Ricardo L. Carrau
Endoscopic expanded endonasal approaches (EEAs) to the skull base are increasingly being used to address a variety of skull base pathologies. Postoperative CSF leakage from the large skull base defects has been well described as one of the most common complications of EEAs. There are reports of associated formation of delayed subdural hematoma and tension pneumocephalus from approximately 1 week to 3 months postoperatively. However, there have been no reports of immediate complications of high-volume CSF leakage from EEA skull base surgery. The authors describe two cases of EEAs in which complications related to rapid, large-volume CSF egress through the skull base surgical defect were detected in the immediate postoperative period. Preventive measures to reduce the likelihood of these immediate complications are presented.
Daniel M. Prevedello, Francesco Doglietto, John A. Jane Jr., Jay Jagannathan, Joseph Han and Edward R. Laws Jr.
✓The history of the endoscope exemplifies the manner in which technological advances influence medicine and surgery. Endoscopic systems have evolved and improved, and they currently provide detailed visualization of a variety of deep organ structures. Otorhinolaryngological surgeons have used the endoscope for more than 30 years. In the 1990s, a number of influential neurosurgeons and otorhinolaryngological surgeons began performing purely endoscopic pituitary surgery. Endoscopic transsphenoidal operations are now extending beyond the sella. The collaboration between otorhinolaryngologists and neurosurgeons has produced a new subspecialty of “endoscopic skull base surgery.” There is a great deal of progress still to be made in developing skills, instruments, and improving skull base repair. The extended skull base approaches allow surgical exposures from the olfactory groove to C-2 and to the infratemporal region and jugular fossa laterally. This article discusses the history of the endoscope, the pivotal technological advances, and the key figures in the burgeoning field of endoneurosurgery.
Danielle de Lara, Leo F. S. Ditzel Filho, Jun Muto, Bradley A. Otto, Ricardo L. Carrau, Daniel M. Prevedello and M.D.
Craniopharyngiomas are notorious for their ability to invade the hypothalamus and third ventricle. Although several transcranial approaches have been proposed for their treatment, the endonasal route provides direct access to the tumor with no need for cerebral retraction or manipulation of the optic apparatus. After the lesion is debulked, the unique angle of approach achieved with this technique enables the surgeon to perform an extra-capsular dissection and visualize the walls of the third ventricle, the foramina of Monro, and the anterior comissure. Moreover, the enhanced magnification and lighting afforded by the endoscope facilitate safe tumor removal, particularly in areas where there is loss of clear lesion delimitation and greater infiltration of the surrounding structures.
Herein we present the case of a 68-year-old female patient with a 3-month history of visual deterioration accompanied by worsening headaches. Investigation with magnetic resonance imaging revealed a heterogeneous mass in the suprasellar region, extending into the third ventricle and displacing the pituitary gland and stalk inferiorly. Hormonal profile was within expected range for her age. An endonasal, fully endoscopic, transplanum transtuberculum approach was performed. Gross-total removal was achieved and pathology confirmed the diagnosis of craniopharyngioma. Postoperative recovery was marked by transient diabetes insipidus. Closure was achieved with a pedicled nasoseptal flap; despite exploration of the third ventricle, there was no cerebrospinal fluid leakage. Pituitary function was preserved. Visual function has fully recovered and the patient has been uneventfully followed since surgery.
The video can be found here: http://youtu.be/it5mpofZl0Q.
Andrew S. Little, Luis Perez-Orribo, Nestor G. Rodriguez-Martinez, Phillip M. Reyes, Anna G. U. S. Newcomb, Daniel M. Prevedello and Neil R. Crawford
Endoscopic endonasal approaches to the craniovertebral junction (CVJ) and clivus are increasingly performed for ventral skull-base pathology, but the biomechanical implications of these approaches have not been studied. The aim of this study was to investigate the spinal biomechanics of the CVJ after an inferior-third clivectomy and anterior intradural exposure of the foramen magnum as would be performed in an endonasal endoscopic surgical strategy.
Seven upper-cervical human cadaveric specimens (occiput [Oc]–C2) underwent nondestructive biomechanical flexibility testing during flexion-extension, axial rotation, and lateral bending at Oc–C1 and C1–2. Each specimen was tested intact, after an inferior-third clivectomy, and after ligamentous complex dissection simulating a wide intradural exposure using an anterior approach. Angular range of motion (ROM), lax zone, and stiff zone were determined and compared with the intact state.
Modest, but statistically significant, hypermobility was observed after inferior-third clivectomy and intradural exposure during flexion-extension and axial rotation at Oc–C1. Angular ROM increased incrementally between 6% and 12% in flexion-extension and axial rotation. These increases were primarily the result of changes in the lax zone. No significant changes were noted at C1–2.
Inferior-third clivectomy and an intradural exposure to the ventral CVJ and foramen magnum resulted in hypermobility at Oc–C1 during flexion-extension and axial rotation. Although the results were statistically significant, the modest degree of hypermobility observed compared with other well-characterized CVJ injuries suggests that occipitocervical stabilization may be unnecessary for most patients.
John A. Jane Jr., Joseph Han, Daniel M. Prevedello, Jay Jagannathan, Aaron S. Dumont and Edward R. Laws Jr.
Sellar tumors are most commonly approached through the transsphenoidal corridor, and tumor resection is most often performed using the operating microscope. More recently the endoscope has been introduced for use either as an adjunct to or in lieu of the microscope. Both the microscopic and endoscopic transsphenoidal approaches to sellar tumors allow safe and effective tumor resection. The authors describe their current endoscopic technique and elucidate the advantages and disadvantages of the pure endoscopic adenomectomy compared with the standard microscopic approach.
Andrew S. Little, Daniel Kelly, John Milligan, Chester Griffiths, Gail Rosseau, Daniel M. Prevedello, Ricardo Carrau, Heidi Jahnke, Charlene Chaloner, Judith O'Leary, Kristina Chapple, Peter Nakaji and William L. White
Patient-reported quality-of-life (QOL) end points are becoming increasingly important health care metrics. To date, no nasal morbidity instrument specifically designed for patients undergoing endonasal skull base surgery has been developed. In this study, the authors describe the development and validation of a site-specific nasal morbidity instrument to assess patient-reported rhinological outcomes following endonasal skull base surgery.
Eligible patients included those with planned endonasal transsphenoidal surgery for sellar pathology identified in outpatient neurosurgical clinics of 3 skull base centers from October 2011 to July 2012. An initial 23-question pool was developed by subject matter experts, review of the literature, and from the results of a previous validation study to assess for common rhinological complaints. Symptoms were ranked by patients from “No Problem” to “Severe Problem” on a 6-point Likert scale. Exploratory factor analysis, change scores, and importance rank were calculated to define the final instrument consisting of 12 items (The Anterior Skull Base Nasal Inventory-12, or ASK Nasal-12). Psychometric validation of the final instrument was performed using standard statistical techniques.
One hundred four patients enrolled in the study. All patients completed the preoperative survey and 100 patients (96%) completed the survey 2–4 weeks after surgery. Internal consistency of the final instrument was 0.88. Concurrent validity measures demonstrated a strong correlation between overall nasal functioning and total scores (p < 0.001). Test-retest reliability measures demonstrated a significant intraclass correlation between responses (p < 0.001). Effect size as calculated by standardized response mean suggested a large effect (0.84). Discriminant validity calculations demonstrated that the instrument was able to discriminate between preoperative and postoperative patients (p < 0.001).
This prospective study demonstrates that the ASK Nasal-12 is a validated, site-specific, unidimensional rhinological outcomes tool sensitive to clinical change. It can be used in conjunction with multidimensional QOL instruments to assess patient-reported nasal perceptions in endonasal skull base surgery. This instrument is being used as a primary outcome measure in an ongoing multicenter nasal morbidity study. Clinical trial registration no.: NCT01504399 (ClinicalTrials.gov).
Alaa S. Montaser, Juan M. Revuelta Barbero, Alexandre Todeschini, André Beer-Furlan, Russell R. Lonser, Ricardo L. Carrau and Daniel M. Prevedello
A 69-year-old female with incidental diagnosis of a dorsum sellae meningioma had shown significant tumor growth after initial conservative management. The procedure started with a microscopic sublabial transsphenoidal approach to the sella and the suprasellar space. Due to limitations to a safe dissection and removal of the retrosellar component, the surgery was converted to a purely endoscopic endonasal approach with left hemi-transposition of the pituitary gland, followed by drilling of the dorsum sellae and removal of the left posterior clinoid process. A complete tumor resection was achieved, and a multilayer skull base reconstruction was performed without complications.
The video can be found here: https://youtu.be/BEolyK-To_A.
Raywat Noiphithak, Juan C. Yanez-Siller, Juan Manuel Revuelta Barbero, Bradley A. Otto, Ricardo L. Carrau and Daniel M. Prevedello
This study proposes a variation of the transorbital endoscopic approach (TOEA) that uses the lateral orbit as the primary surgical corridor, in a minimally invasive fashion, for the posterior fossa (PF) access. The versatility of this technique was quantitatively analyzed in comparison with the anterior transpetrosal approach (ATPA), which is commonly used for managing lesions in the PF.
Anatomical dissections were carried out in 5 latex-injected human cadaveric heads (10 sides). During dissection, the PF was first accessed by TOEAs through the anterior petrosectomy, both with and without lateral orbital rim osteotomies (herein referred as the lateral transorbital approach [LTOA] and the lateral orbital wall approach [LOWA], respectively). ATPAs were performed following the orbital approaches. The stereotactic measurements of the area of exposure, surgical freedom, and angles of attack to 5 anatomical targets were obtained for statistical comparison by the neuronavigator.
The LTOA provided the smallest area of exposure (1.51 ± 0.5 cm2, p = 0.07), while areas of exposure were similar between LOWA and ATPA (1.99 ± 0.7 cm2 and 2.01 ± 1.0 cm2, respectively; p = 0.99). ATPA had the largest surgical freedom, whereas that of LTOA was the most restricted. Similarly, for all targets, the vertical and horizontal angles of attack achieved with ATPA were significantly broader than those achieved with LTOA. However, in LOWA, the removal of the lateral orbital rim allowed a broader range of movement in the horizontal plane, thus granting a similar horizontal angle for 3 of the 5 targets in comparison with ATPA.
The TOEAs using the lateral orbital corridor for PF access are feasible techniques that may provide a comparable surgical exposure to the ATPA. Furthermore, the removal of the orbital rim showed an additional benefit in an enhancement of the surgical maneuverability in the PF.
Luigi M. Cavallo, Daniel M. Prevedello, Domenico Solari, Paul A. Gardner, Felice Esposito, Carl H. Snyderman, Ricardo L. Carrau, Amin B. Kassam and Paolo Cappabianca
The management of recurrent or residual craniopharyngiomas remains controversial. Although possible, revision surgery is more challenging than primary surgery, and more often results in incomplete resection and an increased risk of death and complications. The extended (also called expanded) endoscopic endonasal transsphenoidal approach through the planum sphenoidale has been proposed over the past decade as an alternative surgical route for removal of various suprasellar tumors including craniopharyngiomas. In this study, the authors describe the feasibility and advantages of this technique in recurrent or symptomatic residual craniopharyngiomas.
Between January 2004 and June 2008, 22 patients underwent surgery via the extended endoscopic transsphenoidal approach for the treatment of recurrent or residual symptomatic craniopharyngiomas at either the University of Pittsburgh or the Universita degli Studi di Napoli. The lesions included 12 purely suprasellar craniopharyngiomas, 9 with both intra- and suprasellar extensions, and 1 arising from a remnant in the Meckel cave. To better evaluate the features of the extended endonasal approach for recurrent or residual craniopharyngiomas, each patient was assigned to 1 of 3 subgroups depending on the original surgical treatment: transcranial pterional route (13 patients), transphenoidal approach (3 patients; 2 microsurgically and 1 with the standard endoscopic technique), or extended endonasal endoscopic approach (6 patients).
Total removal was achieved in 9 patients (40.9%), and in 8 patients (36.4%) near-total removal (defined as > 95% removal) was possible. Subtotal removal (> 70%) was attained in 4 patients (18.2%), and tumor removal was partial (< 50%) in only 1 case (4.5%). There were no deaths or major complications, including behavior changes. Postoperative CSF leaks developed in 2 patients in the transcranial subgroup, and 1 in the transsphenoidal subgroup (overall rate 13.6%), requiring early successful endoscopic revision surgery for the cranial base defect.
Most of the advantages of the endoscopic endonasal technique were noted during tumor dissection from the inferior aspect of the chiasm, the infundibulum, the third ventricle, and/or the retro- and parasellar areas. These benefits were best appreciated in patients who had originally undergone transcranial surgery, since in such cases the authors' endoscopic endonasal approach was a virgin route. However, the extended endoscopic endonasal technique can also be safely used in patients who originally underwent transsphenoidal surgery. The endoscopic endonasal technique should be considered as a therapeutic option in selected cases of recurrent or symptomatic residual craniopharyngiomas.