Adjacent Skull Base Research Articles

Exploring the uncharted: adenoid cystic carcinoma nestled in temporal bone

BackgroundAdenoid cystic carcinoma is an uncommon malignancy primarily arising from salivary glands. An extremely rare site for adenoid cystic carcinoma is the skull base. We report a case of adenoid cystic carcinoma of skull base who presented with common complaints of pain and right ear discharge. The discussion is made with emphasis on imaging evaluation simulating infective etiology with adjacent skull base osteomyelitis. Careful observation of the imaging findings and further evaluation of the patient revealed the neoplastic nature of the lesion with the final diagnosis being adenoid cystic carcinoma.Case presentationA 40-year-old female presented to our department with complaints of pain and right ear discharge since 6 months with progressive, extensive facial swelling and facial nerve palsy. The patient had undergone modified radical mastoidectomy thrice, but the details were not available. On imaging, there was a heterogenous extensive lesion extending from scalp till upper cervical region with extensive destruction of skull base and intra-cranial extension. The possibilities of temporal bone squamous cell carcinoma and extensive skull base osteomyelitis were considered. Further the biopsy of the lesion revealed adenoid cystic carcinoma.ConclusionsExtensive lesions of the skull base can be of infective, neoplastic and inflammatory etiology. Distinguishing between these conditions is crucial, as they have similar imaging characteristics but require different management approaches. The presence of a lesion that displaces or destroys fascial planes, accompanied by solid mass-like enhancement, indicates a higher probability of a neoplastic origin rather than an infectious etiology. With squamous cell carcinoma being the most common neoplasm, adenoid cystic carcinoma of the skull base also needs to be understood due to its propensity for perineural spread and a high likelihood of recurrence.

Anatomical Step-by-Step Dissection of Midline Suboccipital Approaches to the Fourth Ventricle for Trainees: Surgical Anatomy of the Telovelar, Transvermian, and Superior Transvelar Routes, Surgical Principles, and Illustrative Cases.

Introduction Safe, effective access to the fourth ventricle for oncologic resection remains challenging given the depth of location, restricted posterior fossa boundaries, and surrounding eloquent neuroanatomy. Despite description in the literature, a practical step-by step dissection guide of the suboccipital approaches to the fourth ventricle targeted to all training levels is lacking. Methods Two formalin-fixed, latex-injected specimens were dissected under microscopic magnification and endoscopic visualization. Dissections of the telovelar, transvermian, and supracerebellar infratentorial-superior transvelar approaches were performed by one neurosurgery resident (D.D.D.), under guidance of senior authors. The dissections were supplemented with representative clinical cases to highlight pertinent surgical principles. Results The telovelar and transvermian corridors afford excellent access to the caudal two-thirds of the fourth ventricle with the former approach offering expanded access to the lateral recess, foramen of Luschka, adjacent skull base, and cerebellopontine angle. The supracerebellar infratentorial-superior transvelar approach reaches the rostral third of the fourth ventricle, the cerebral aqueduct, and dorsal mesencephalon. Key steps described include positioning and skin incision, myofascial dissection, burr hole and craniotomy, durotomy, the aforementioned transventricular routes, and identification of relevant skull base landmarks. Conclusion The midline suboccipital craniotomy represents a foundational cranial approach, particularly for lesions involving the fourth ventricle. Operatively oriented resources that combine stepwise neuroanatomic dissections with representative cases provide a crucial foundation for neurosurgical training. We present a comprehensive guide for trainees in the surgical anatomy laboratory to optimize familiarity with fourth ventricle approaches, mastery of relevant microsurgical anatomy, and simultaneous preparation for learning in the operating room.

長期間の抗菌薬経静脈投与を要した頭蓋底骨髄炎例

Skull-base osteomyelitis occurs as a result of spread of inflammatory disease around the temporal bone into the adjacent skull base, and carries a poor prognosis. Occasionally, patients present with paralysis of the lower cranial nerves, which further worsens the survival. Prolonged intravenous antibiotic therapy for six to eight weeks is needed for treatment. Herein, we present a case of skull-base osteomyelitis caused by Pseudomonas aeruginosa that developed in a 78-year-old male patient with diabetic nephropathy who was under maintenance hemodialysis. He presented to our hospital with the complaints of earache and otorrhea on the left side. Exploratory tympanotomy revealed pus and granulation tissue filling the tympanic cavity and mastoid, and destruction of the tympanic portion of the temporal bone; based on the findings and results of pus culture, we made the diagnosis of skull-base osteomyelitis caused by Pseudomonas aeruginosa. While the osteomyelitis was gradually improving with intravenous meropenem, the patient desired early discharge from the hospital. Therefore, the intravenous antibiotic therapy was switched earlier than intended to oral antimicrobial therapy, which led to progression of the disease, and the patient presented with lower cranial nerve palsies three months after his discharge. He was initiated again on intravenous meropenem. While the osteomyelitis improved gradually with the intravenous antimicrobial therapy for two months, the levels of inflammatory markers, such as the serum c-reactive protein, increased again soon after discontinuation of the intravenous antibiotic therapy. Therefore, we decided to continue the patient on intravenous meropenem every other day administered at the outpatient clinic after dialysis. The treatment was continued for four months after discharge, and the improvement was maintained. We reaffirmed the importance of long-term intravenous antibiotic therapy to treat skull-base osteomyelitis. Intravenous antibiotic administration every other day at the outpatient clinic after dialysis could be a useful treatment strategy to treat skull-base osteomyelitis in patients under maintenance hemodialysis.

Audiometric and Otologic Findings in Children and Young Adults with Neurofibromatosis Type 1 and Plexiform Neurofibromas.

To characterize otologic and audiologic manifestations in our NF1 cohort and explore the relationship between otologic and audiologic findings in a subset of patients with ear-related plexiform neurofibromas (PNs). Audiologic and otologic clinical evaluations were conducted on 102 patients with NF1 in a natural history study (5-45 years; M=14.4 years; Mdn=14). Testing included pure tone and speech audiometry, middle ear function, neurodiagnostic auditory brainstem response (ABR), auditory processing, and MRIs of the head and neck region. Patients referred to this study had an overall higher incidence and burden of PNs than the overall NF1 population. The majority of subjects in this cohort had normal hearing sensitivity (81%) and normal middle ear function (78%). Nineteen participants had hearing loss that ranged in degree from mild to profound, with the majority in the mild range. Hearing loss was twice as likely to be conductive than sensorineural. In patients with ear-related PNs (n=12), hearing loss was predominantly conductive (60%). Seventy-five percent of ears with PNs had atypical tympanometric tracings that could not be characterized by the classic categories. In all 20 patients with a PN in the temporal bone, the ear canal was affected, and the PNs often extended to the surrounding soft tissue regions. People with NF1-related PNs in the temporal bone and adjacent skull base should have audiometric and otologic monitoring. Addressing hearing concerns should be part of routine clinical evaluations in patients with NF1. Magnetic resonance imaging (MRI) should be performed in patients with NF1 who have hearing loss. 3 Laryngoscope, 133:2770-2778, 2023.

Greater Palatine Canal: Computed Tomography-Based Anatomic Analysis And Clinical Significance for the Sinus and Skull Base Surgeon.

Our aim is to describe the location and course of the greater palatine canal (GPC) by analyzing its relationship with anatomical landmarks that can be used during endoscopic sinus surgery. This information might help prevent injury to the neurovascular bundle. A retrospective evaluation of paranasal sinus CT scans of 100 consecutive random patients, 200 sides, was performed. Five measurements related to the course of the GPC were conducted, from cranial to caudal. The anatomical landmarks were the inferior bony border of the sphenopalatine foramen to the cranial entrance of the GPC, the distance from the most dorsal, and inferior bony insertion of the middle turbinate and the inferior turbinate bones to the anterior margin of the GPC. The angle between the horizontal palatine bone and the GPC, its length, and the prevalence of osteophytes in GPC was also assessed. The mean distance of the inferior border of the sphenopalatine foramen to the cranial entrance of the GPC was 9.39 ± 1.72mm. The mean distance of the dorsal insertion of the middle turbinate to the anterior margin of the GPC was 3.89 ± 0.93mm. The distance of the dorsal insertion of the inferior turbinate to the anterior margin of the GPC was 3.16 ± 0.81mm. The mean angle between the horizontal palatine bone and the GPC was 114.33 ± 10.92º and the mean length of the GPC was 30.23 ± 3.74mm. None of the measurements showed a significant difference between the two sides. The landmarks used are easy to locate and assess on CT scans. These findings may help to make dissection safer in pathologies related to the pterygopalatine fossa, lateral sphenoid sinus or adjacent skull base.

Unusual case of skull base adenoid cystic carcinoma presenting as skull base osteomyelitis: case report

BackgroundAdenoid cystic carcinoma is a rare malignancy. Tumours of palatal region with minor salivary gland origin do not generally present at an early stage as the tumour is submucosal with symptoms prevalent only when there is evidence of perineural spread of the tumour. We report a case of adenoid cystic carcinoma of the palate with rare presentation of left ear discharge and diplopia on left lateral gaze. We discuss the case with emphasis on imaging evaluation mimicking a case of infective etiology with adjacent skull base osteomyelitis on initial presentation. However, on follow-up and further evaluation the patient was diagnosed as adenoid cystic carcinoma of hard palate on left side.Case presentationA 25-year-old male patient has presented to Jagadguru Sri Shivarathreeswara Hospital in August 2019 with complaints of left ear discharge and diplopia on left lateral gaze since 1 week. The clinical and imaging findings was suggestive of infective etiology and the patient was treated for the same with IV antibiotics. Repeat magnetic resonance imaging was then done which revealed definitive reduction in the severity of inflammation suggestive of response to therapy. Patient was then discharged and was followed up. Three months later, the patient came with complaints of mass in left nasal cavity. Patient was then referred for contrast enhanced computed tomography neck strongly suggestive of neoplastic etiology. The patient was then operated and histopathological examination of the biopsy revealed adenoid cystic carcinoma.ConclusionsTumours of palatal region with minor salivary gland origin do not generally present at an early stage as the tumour is submucosal with symptoms prevalent only when there is evidence of perineural spread of the tumour. In our case patient presented with lateral rectus palsy, involvement of meckel’s cave, trigeminal nerve involvement and cavernous sinus involvement which are strong indicators of the perineural and locoregional spread of the tumour. Hence, it is important for the radiologist and clinician to strongly suspect and evaluate for a primary lesion of the head and neck when such a radiological presentation has been demonstrated.

Management Strategies of Fibrous Dysplasia Involving the Paranasal Sinus and the Adjacent Skull Base.

Current management of fibrous dysplasia (FD) involving the paranasal sinuses and the adjacent skull base is currently controversial. This study aims to present our experience in the management strategy of FD that involves the paranasal sinuses and the adjacent skull base. Twenty three patients from 2006 to 2019 with monostotic fibrous dysplasia (MFD), polyostotic fibrous dysplasia (PFD), or McCune-Albright syndrome (MAS) involving the paranasal sinuses and the adjacent skull base were retrospectively reviewed. This study series was divided into 3 groups based on management strategies: the observation group, the surgery group, and the optic nerve decompression group. The observation group included 9 patients with asymptomatic MFD with stable condition during the follow-up period of 15 to 164 months. The surgery group included 10 symptomatic patients with MFD who had personalized endoscopic endonasal surgery. The symptoms of the patients were relieved after surgery. The optic nerve decompression group included 4 patients with visual loss, who underwent endonasal endoscopic optic nerve decompression (EOND) with the aid of image-guided navigation. Their vision improved after surgery. Clinical observation and periodic computed tomography (CT) scan are adopted for asymptomatic patients. Surgery is indicated in symptomatic patients. Optic nerve decompression is recommended as soon as possible if the patient has visual loss, whereas prophylactic decompression is not recommended if the optic nerve is encroached by FD without visual loss. Navigation plays an important role in endoscopic surgery involving the paranasal sinuses and the adjacent skull base, especially in FD resection and optic nerve decompression.

Posterior Clinoid Meningioma-A Formidable Entity: 2-Dimensional Operative Video.

Meningiomas originating from the posterior clinoid process are the rarest form of meningioma making up less than 1% of skull base meningiomas.1 These tumors have notoriously poor outcomes characterized by incomplete resections and a litany of complications.1 Owing to their scarcity and frequent confusion with meningiomas arising from adjacent skull base regions, the surgical anatomy, technical nuances, and potential pitfalls are not well addressed in modern literature. The most challenging aspect of the resection occurs while dissecting tumor in the retrosellar space.2 Meningiomas of neighboring regions such as those of the tuberculum, anterior clinoid process, or petrous apex, all arise from above the membrane of Liliequist which provides a plane of tumor dissection from the neurovascular structures of the posterior fossa. Posterior clinoid meningiomas arise from beneath this arachnoidal membrane and thus lack its protection while dissecting tumor from the basilar artery and its perforators.3,4 Surgical resection of these tumors requires meticulous intra-arachnoidal dissection of the encased basilar artery and its branches, and separation of tumor from the hypothalamus, cranial nerves, pituitary stalk, and brainstem while preserving their vascular supply. The combined petrosal facilitates a wide exposure reaching the entire central skull base for the safe visualization and dissection of tumor along the length of the basilar and the hypothalamus.5,6 The patient is a 68-year-old woman with hemiparesis and seizures from a posterior clinoid meningioma. The tumor was resected using the combined petrosal approach. The patient has consented to surgery and publication of images. {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"VIDEO.","caption":"","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_279na25v"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]}

Utility of 7 Tesla MRI for Preoperative Planning of Endoscopic Endonasal Surgery for Pituitary Adenomas.

Objective There is increasing interest in investigating the utility of 7 Tesla (7 T) magnetic resonance imaging (MRI) for imaging of skull base tumors. The present study quantifies visualization of tumor features and adjacent skull base anatomy in a homogenous cohort of pituitary adenoma patients. Methods Eighteen pituitary adenoma patients were scanned at 7 T in this prospective study. All patients had reference standard-of-care clinical imaging at either 3 T (7/18, 39%) or 1.5 T (11/18, 61%). Visualization of tumor features and conspicuity of arteries and cranial nerves (CNs) was rated by an expert neuroradiologist on 7 T and clinical field strength MRI. Overall image quality and severity of image artifacts were also characterized and compared. Results Ability to visualize tumor features did not differ between 7 T and lower field MRI. Cranial nerves III, IV, and VI were better detected at 7 T compared with clinical field strength scans. Cranial nerves III, IV, and VI were also better detected at 7 T compared with only 1.5 T, and CN III was better visualized at 7 T compared with 3 T MRI. The ophthalmic arteries and posterior communicating arteries (PCOM) were better detected at 7 T compared with clinical field strength imaging. The 7 T also provided better visualization of the ophthalmic arteries compared with 1.5 T scans. Conclusion This study demonstrates that 7 T MRI is feasible at the skull base and identifies various CNs and branches of the internal carotid artery that were better visualized at 7 T. The 7 T MRI may offer important preoperative information that can help to guide resection of pituitary adenoma and reduce operative morbidity.

Skull base anatomy and surgical safety in isolated and CHARGE-associated bilateral choanal atresia

IntroductionBilateral choanal atresia (BCA) is associated with a high incidence of congenital abnormalities that include skull base anomalies and defects. Surgical repair of BCA is necessary in the early neonatal period and any altered anatomy of the adjacent skull base will heighten the risk of intracranial injury. This risk may be further increased in patients with CHARGE syndrome. ObjectivesTo measure surgically relevant nasal and skull base dimensions in neonates with BCA in order to determine whether any difference exists between isolated and CHARGE syndrome associated subgroups, thereby optimizing the safety of surgical repair. MethodsA retrospective review of medical charts and computed tomography was undertaken at a tertiary pediatric hospital of all neonates diagnosed with BCA between 2004 and 2016. Isolated and CHARGE syndrome subgroups of BCA were identified from clinical records and CT data was analyzed and compared between the two. The skull base parameters measured were choanal width, choanal height, mid-nasal skull base height and skull base slope. ResultsOf the 13 patients included, 3 had CHARGE syndrome and 10 had isolated BCA. Whilst the difference in mid-nasal height approached significance for the two groups, numbers were too small for a statistical difference to be identified. The mean value for choanal width in the isolated BCA group was significantly less the largest series of normative data available in the literature for comparison (p < 0.001). No skull base anomalies were noted in either group. ConclusionWhile this is a small study with limited numbers, it is the first that has attempted to identify and measure the posterior nasal and skull base anatomy most pertinent to avoiding skull base injury in the surgical management of BCA.

Large parasagittal meningioma in a pregnant woman

Large parasagittal meningioma is rare in pregnant women. In this paper, we report the successful treatment of a pregnant woman with a large parasagittal meningioma. A 35-year-old woman in her 37th week of pregnancy presented with acute consciousness disturbances after experiencing headache and nausea for 2 weeks. We performed a successful cesarean delivery under general anesthesia, and immediately after the delivery, brain computed tomography was performed. The scan revealed a large tumor (8.3 × 6.8 × 7.1 cm3) in the left frontal region, thickening of the adjacent skull base, and perifocal edema. Twenty-four hours after the delivery, the patient underwent imaging studies, namely, magnetic resonance imaging and angiography. The parasagittal meningioma was removed through craniotomy, and the surgical outcome was highly satisfactory. Although meningioma is benign, the tumor mass can expand rapidly during pregnancy. In our patient, an early cesarean section was first performed for a successful delivery, and imaging studies and transarterial embolization of the tumor blood supply were performed prior to the second operation for craniotomy and total tumor excision. A multidisciplinary team was critical for successfully treating this patient.

Piezosurgery for the repair of middle cranial fossa meningoencephaloceles.

To describe the use of a piezosurgery medical device to perform a craniotomy and produce a split calvarial graft for the repair of middle cranial fossa meningoencephaloceles. Retrospective case review. Tertiary referral hospital. Ten consecutive patients undergoing middle cranial fossa approach for the repair of meningoencephaloceles. Therapeutic. Intraoperative and postoperative complications, success rate as defined by the ability to fashion a split calvarial graft that achieves complete closure of the tegmen defect. As a secondary outcome measure, evidence of integration of the split calvarial bone graft with the adjacent skull base was assessed. There were no intraoperative or postoperative complications. An appropriately sized calvarial bone graft was produced, and complete closure of the tegmen defect was achieved in all 10 cases. Computed tomography demonstrated evidence of integration of the bone graft in eight cases between 4 and 9 months after surgery. The piezosurgery medical device provides a safe and effective means by which the middle fossa craniotomy and split calvarial bone graft can be produced to repair defects of the middle fossa tegmen, with integration of the bone graft in the majority of cases.

Fibrous dysplasia of the sinonasal tract and adjacent skull base

Fibrous dysplasia is a rare condition characterized by replacement of normal bone by fibro-osseous connective tissue exhibiting varying degrees of osseous metaplasia, which can affect the craniofacial complex. This article reviews the recent literature with the intent to highlight the innovative information that has contributed to elucidate the pathophysiology, diagnostic criteria, and treatment principles of the disease. A mutation in the GNAS1 gene on chromosome 20 has been identified as the molecular hallmark of fibrous dysplasia. This finding is not present in ossifying fibroma, which has been traditionally included in differential diagnosis. The concept that asymptomatic patients do not require surgical treatment has been reinforced by a meta-analysis specifically addressing the issue of optic nerve decompression. A diagnosis of fibrous dysplasia can be achieved by combined assessment of clinical, radiologic, and pathologic findings. There is general agreement that, when the disease is not associated with symptoms, partial or radical resection is not indicated, but patients do require periodic radiologic evaluations. There is, however, an absolute need for prospective studies to identify factors predicting the possible late growth of the disease and to investigate the efficacy and side-effects of pharmacological treatment with biphosphonates.

Minimally invasive endoscopic resection of sinonasal and anterior skull base malignant neoplasms

The evolution of minimally invasive endoscopic techniques, coupled with advances in surgical instrumentation and computer-aided surgery, has greatly facilitated the management of complex sinonasal and skull-base pathology. This accrued experience has facilitated consideration of the treatment of malignant neoplasms of the paranasal sinuses and skull base via the endoscopic route. This strategy uses the rigid endoscope as the primary surgical modality for resection of neoplasms within the paranasal sinus confines, along with the adjacent orbit and skull base. The endoscopic approach has been demonstrated to be effective, with surgical outcomes approaching the traditional open craniofacial resection, providing unparalleled visualization, avoidance of facial incisions and reduction in morbidity. This article outlines the salient components of the endoscopic paradigm for minimally invasive tumor resection, focusing on requisite technology, surgical techniques and patient outcomes.

Extradural Dermoid Cyst of the Parasellar Region: A Case Report

Dermoid cysts are rare congenital intracranial tumors. Among these tumors, extradural localization is extremely rare. We report a patient with an extradural dermoid cyst of the right parasellar region, causing right visual disturbance. Computed tomography revealed a hypodense mass lesion with rimlike calcification at the right parasellar region, accompanying marked erosion of the adjacent skull base. The tumor appeared as a heterogeneous intensity on magnetic resonance imaging and was surrounded by thin gadolinium enhancement without inner enhancement. The right optic nerve was compressed by the tumor. Surgical resection was successfully performed using a right frontotemporal extradural approach. The entire tumor was completely resided extradurally and was enclosed by saclike, stretched dura mater and extended deeply into the skull base. Histopathologic findings were consistent with the features of dermoid cyst. The postoperative course was uneventful, and the visual disturbance improved. Neuroradiological features, strategies for surgical treatment, and mechanisms responsible for preoperative symptoms are discussed.

Approaches to the pterygopalatine space—Caldwell-Luc and beyond

Before the development of endoscopic skull-based surgical techniques, external surgical approaches with facial incisions often were used to access lesions of the pterygopalatine space (PPS) and beyond. Lesions of the PPS and adjacent skull base areas include juvenile nasal angiofibromas, schwannomas, lymphoma, fungal infections, cerebrospinal fluid (CSF) leaks, and metastatic malignancies. Traditional approaches included midface degloving, lateral rhinotomy with medial maxillectomy, Caldwell-Luc, and subtemporal craniotomy. Recent advances in endoscopic technology, endoscopic instrumentation, and stereotactic navigation have markedly augmented minimally invasive approaches for these pathologies.

New developments in transnasal endoscopic surgery for malignancies of the sinonasal tract and adjacent skull base

Technological advances and technical innovations have spearheaded an expansion in the indications for endoscopic sinonasal surgery, which now extend to the resection of sinonasal and skull base malignancies. This review examines recent advances that have contributed to make this technique feasible and reviews the basis of adopting an endonasal approach. Oncologic goals developed for traditional skull base surgery can be safely applied to endoscopic skull base surgery. This has been made possible with the advent of better understanding of skull base anatomy from the endonasal perspective, as well as the development of better instrumentation, better hemostatic materials and more reliable reconstructive techniques. Recent publications have reported similar short-term outcomes for endoscopic skull base resection as compared with traditional approaches with lower complication rates. Transnasal endoscopic surgery is an important part of the surgical armamentarium for the treatment of sinonasal and skull base malignancies. New technologies will further expand the limits of what can be achieved endoscopically. Collaborative multiinstitutional studies with long-term follow-up are crucial in defining the role of endoscopic resection in the treatment of skull base malignancies.

The Role of Palliative Radiosurgery When Cancer Invades the Cavernous Sinus

Involvement of the cavernous sinus by direct invasion from skull base cancer or from metastatic spread of cancers is a challenging problem. We evaluated the role of stereotactic radiosurgery (SRS) in the treatment of patients who developed cavernous sinus metastases or direct invasion. We retrospectively reviewed the data from 37 patients who had cavernous sinus metastases or had cavernous sinus invasion from adjacent skull base cancers and who underwent SRS between 1992 and 2006 at the University of Pittsburgh Medical Center. The median patient age was 57.8 years. Previous adjuvant management included fractionated radiotherapy in 8, chemotherapy in 16, and both radiotherapy and chemotherapy in 5. The primary sites of metastases or invasion were nasopharyngeal carcinoma (n = 7), parotid gland carcinoma (n = 7), and metastases from systemic cancer (n = 23). The median target volume was 6.3 cm(3) (range, 0.3-33.6), and the median margin dose was 14 Gy (range, 12-20). At a mean of 12.9 months (range, 0.8-63.9), 32 patients had died and 5 were living. The overall survival rate after SRS was 36.6% and 19.4% at 1 and 2 years, respectively. Progression-free survival was related to a greater marginal dose. After SRS, 12 (35.3%) of 34 patients with neurologic symptoms exhibited improvement. SRS early after diagnosis was significantly associated with improvement of cranial nerve dysfunction. SRS is a minimally invasive palliative option for patients whose cancer has invaded the cavernous sinus. The benefits for cranial nerve deficits are best when SRS is performed early.

Endoscopic Surgery for Malignant Tumors of the Sinonasal Tract and Adjacent Skull Base: A 10-year Experience

The increasing expertise in the field of transnasal endoscopic surgery recently has expanded its indications to include the management of sinonasal malignancies. We report our experience with the endoscopic management of nasoethmoidal malignancies possibly involving the adjacent skull base. A retrospective analysis was performed of patients treated by an exclusive endoscopic approach (EEA) or a cranioendoscopic approach (CEA) from 1996 to 2006 managed by two surgical teams at the Departments of Otorhinolaryngology of the University of Brescia, and the University of Pavia/Insubria-Varese, Italy. One-hundred eighty-four patients were considered eligible for the present analysis. An EEA was performed in 134 patients and the remaining 50 patients underwent the CEA. The most frequent histotypes encountered were adenocarcinoma (37%), squamous cell carcinoma (13.6%), olfactory neuroblastoma (12%), mucosal melanoma (9.2%), and adenoid cystic carcinoma (7.1%). Overall, 86 (46.7%) patients received some form of adjuvant treatment. The patients were followed up for a mean of 34.1 months (range, 2-123 months). The 5-year disease-specific survival was 91.4 +/- 3.9% and 58.8 +/- 8.6% (p = 0.0004) for the EEA and CEA group, respectively. To the best of our knowledge, this is the largest series reported to date of malignant tumors of the sinonasal tract and adjacent skull base treated with pure endoscopic or cranioendoscopic techniques. A 5-year disease-specific survival of 91.4% and 58.8% for the EEA and the CEA groups, respectively, seem to indicate that endoscopic surgery, when properly planned and in expert hands, may be a valid alternative to standard surgical approaches for the management of malignancies of the sinonasal tract.

Sphenoid Sinus Fungal Balls

We sought to examine the nature of fungal balls of the sphenoid sinus, in particular the exposure of adjacent skull base structures and the potential for surgical morbidity. We retrospectively reviewed our series of 17 cases of sphenoid sinus fungal balls seen between 1998 and 2005 with reference to their diagnosis, radiologic changes, histopathology, and surgical management. Exposed structures included the pituitary fossa, cavernous sinus, and cavernous internal carotid artery, but this exposure did not result in an increase in perioperative complications. Sclerotic thickening of the sinus walls persisted, probably representing a chronic osteitis in response to concurrent bacterial infection. This appeared to be protective against further sinus wall erosions. Wall erosions did not heal. One patient demonstrated what appeared to be invasive fungal disease from a fungal ball. Sphenoid sinus fungal balls can occur with minimal symptoms in a mainly elderly population and require surgical removal. Sphenoid sinus fungal balls have a low rate of operative morbidity and should be effectively managed by transnasal endoscopic sphenoidotomy alone.