Cavernous Sinus: A Comprehensive Review of its Anatomy, Pathologic Conditions, and Imaging Features

Cavernous Sinus Metastasis From Laryngeal Cancer Identified by 18F-FDG PET/MR

ABSTRACT

Cavernous sinus metastasis from head and neck cancers is rare. We report FDG PET/MRI findings of cavernous sinus metastases from laryngeal cancer in a 56-year-old woman. The images revealed isointense lesions in the bilateral cavernous sinus on T2-weighted MR, with slight enhancement, and intense FDG uptake. The lesions were confirmed as metastases to the cavernous sinus.

A New Perspective on the Cavernous Sinus as Seen through Multiple Surgical Corridors: Anatomical Study Comparing the Transorbital, Endonasal, and Transcranial Routes and the Relative Coterminous Spatial Regions

Background: The cavernous sinus (CS) is a highly vulnerable anatomical space, mainly due to the neurovascular structures that it contains; therefore, a detailed knowledge of its anatomy is mandatory for surgical unlocking. In this study, we compared the anatomy of this region from different endoscopic and microsurgical operative corridors, further focusing on the corresponding anatomic landmarks encountered along these routes. Furthermore, we tried to define the safe entry zones to this venous space from these three different operative corridors, and to provide indications regarding the optimal approach according to the lesion's location. Methods: Five embalmed and injected adult cadaveric specimens (10 sides) separately underwent dissection and exposure of the CS via superior eyelid endoscopic transorbital (SETOA), extended endoscopic endonasal transsphenoidal-transethmoidal (EEEA), and microsurgical transcranial fronto-temporo-orbito-zygomatic (FTOZ) approaches. The anatomical landmarks and the content of this venous space were described and compared from these surgical perspectives. Results: The oculomotor triangle can be clearly exposed only by the FTOZ approach. Unlike EEEA, for the exposure of the clinoid triangle content, the anterior clinoid process removal is required for FTOZ and SETOA. The supra- and infratrochlear as well as the anteromedial and anterolateral triangles can be exposed by all three corridors. The most recently introduced SETOA allowed for the exposure of the entire lateral wall of the CS without entering its neurovascular structures and part of the posterior wall; furthermore, thanks to its anteroposterior trajectory, it allowed for the disclosure of the posterior ascending segment of the cavernous ICA with the related sympathetic plexus through the Mullan's triangle, in a minimally invasive fashion. Through the anterolateral triangle, the transorbital corridor allowed us to expose the lateral 180 degrees of the Vidian nerve and artery in the homonymous canal, the anterolateral aspect of the lacerum segment of the ICA at the transition zone from the petrous horizontal to the ascending posterior cavernous segment, surrounded by the carotid sympathetic plexus, and the medial Meckel's cave. Conclusions: Different regions of the cavernous sinus are better exposed by different surgical corridors. The relationship of the tumor with cranial nerves in the lateral wall guides the selection of the approach to cavernous sinus lesions. The transorbital endoscopic approach can be considered to be a safe and minimally invasive complementary surgical corridor to the well-established transcranial and endoscopic endonasal routes for the exposure of selected lesions of the cavernous sinus. Nevertheless, peer knowledge of the anatomy and a surgical learning curve are required.

Hypopituitarism and cranial nerve involvement mimicking Tolosa-Hunt syndrome as the initially presenting feature of diffuse large B-cell lymphoma: a case report

BACKGROUND

Early diagnosis of lymphoma involving the central nervous system is sometimes difficult but emergent to avoid the delay of therapeutic initiation. Pituitary insufficiencies are usually associated with lymphoma in the pituitary gland. There have been no cases of lymphoma originating from extra pituitary gland with hypopituitarism that simultaneously presenting unilateral upper cranial nerve palsies and ophthalmalgia. These symptoms are mostly caused by neoplastic involvement of the skull base or benign diseases such as Tolosa-Hunt syndrome (THS). We report a case of lymphoma with unique clinical courses initially presenting hypopituitarism and symptoms mimicking THS with a mass in sphenoidal and cavernous sinuses accompanying sphenoidal bone erosion.

CASE PRESENTATION

A 71-year-old woman visited our hospital with left ophthalmalgia, ptosis, and diplopia. Neurological findings revealed left oculomotor, trochlear and abducent nerve palsies. Endocrine tests indicated partial hypopituitarism. Initial CT and MRI revealed that a mass in sphenoidal and cavernous sinuses had invaded the sella with osteolysis of the sphenoid bone. At around four weeks, almost all the symptoms of cranial nerve palsies were relieved. Seven weeks later, she had a high fever and cervical lymph node (CLN) swellings. CLN biopsy revealed CD20-positive B-cells. She was diagnosed with diffuse large B-cell lymphoma (DLBCL). ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) revealed elevated uptake at the erosion lesion of the sphenoidal bone, but not the pituitary gland. After chemotherapy, all the symptoms related to systemic lymphoma were relieved, but partial hypopituitarism remained. The mass in sphenoidal and cavernous sinuses and elevated uptake by PET/CT were dissolved.

CONCLUSION

This case of DLBCL had a unique clinical course; initial presentation of hypopituitarism and symptoms mimicking THS. There was also rare demonstration of mass lesions related to DLBCL in the sphenoidal and cavernous sinuses compressing the pituitary gland through an eroded area of the sphenoidal bone. It should be clinically cautioned that DLBCL can be associated with erosion of the sphenoidal bone and cause both hypopituitarism and THS-mimicking symptoms.

Cavernous Sinus Dural Arteriovenous Fistula in a Patient with Thyroid-Associated Ophthalmopathy: Complete Resolution after Medical Treatment

Thyroid-associated ophthalmopathy (TAO) is a well-known and frequent epiphenomenon of a hyperthyroid autoimmune disease that can present with proptosis, strabismus, and diplopia. Ophthalmopathy can occur in the absence of overt Graves’ disease, even in euthyroid patients. Cavernous sinus dural fistulas (CS-DAVF) are abnormal communications between the cavernous sinus (CS) and dural branches from internal carotid or external carotid arteries. They can often present with ocular symptoms that can mimic a thyroid-associated ophthalmopathy. CS-DAVF are usually successfully treated with an endovascular embolization that can be pursued both through a transvenous or transarterial approach. TAO and CS-DAVF can coexist especially when the ocular symptoms are unilateral. In those cases, an endovascular embolization is usually curative, but sometimes the procedure can fail. Our hypothesis is that some cases of CS-DAVF may be of secondary nature (i.e., caused by compression of the venous outlet by the hypertrophic ocular muscles); therefore, treating the ocular disease with medical therapy may solve the vascular problem as well. We present a case of a CS-DAVF in a patient with TAO successfully treated with sole medical therapy after the failure of a first-line endovascular treatment.

Isolated Sixth Nerve Palsy as the First Manifestation of Cavernous Sinus Metastasis From Primary Breast Cancer

Cavernous sinus metastasis is a rare clinical finding, presenting most commonly with complaints of headache, diplopia, visual field defects, facial pain, and progressive neurological deficits. Many patients present with features of III, IV, and VI nerve palsies. We hereby report an unusual case of cavernous sinus metastasis from primary breast cancer in a 40-year-old female, who presented with binocular diplopia due to left VI nerve palsy as the first presenting complaint. The patient had a history of surgery for left breast cancer which was performed at another center. Contrast-enhanced computed tomography (CECT) scan of thorax and abdomen revealed a residual neoplastic left breast mass with satellite nodules, left axillary lymphadenopathy, and hepatic, splenic, and skeletal metastasis. Contrast-enhanced magnetic resonance imaging (CE-MRI) of brain and orbit showed enhancing lesion of 20 mm x 10 mm along the lateral wall of left cavernous sinus and left petrous apex. She was referred to radiation oncology department for further management. This case report highlights the importance of ophthalmologists in such life-threatening conditions, who may first present to them.

Classification of Pituitary Adenomas Invading the Cavernous Sinus Assisted by Three-Dimensional Multimodal Imaging and Its Clinical Application

Introduction  To help diagnose and evaluate the prognosis of pituitary adenoma with cavernous sinus (CS) invasion and guide endonasal endoscopic surgery (EES) assisted by intraoperative navigation (ION) with three-dimensional multimodal imaging (3D-MMI). We propose a classification of CS invasion based on 3D-MMI. Methods  We picked some appropriate cases and reconstructed the 3D-MMI and then classified them into 3 grades according to the stereo relationship among ICA, tumor and CS in 3D-MMI. Then, we applied different strategies according to their grade to remove pituitary adenomas that invaded the CS. Results  All 38 patients were divided into 3 grades. Tumors compressing the ICA and CS without CS invasion were divided into grade 1. Tumors encasing the ICA and invading the superior-posterior compartment and/or anterior-inferior compartment but without distinct separation of the ICA and CS lateral wall were deemed as grade 2. Tumors encasing the ICA and filling the lateral compartment of the CS that dissociated the lateral wall from the ICA were deemed as grade 3. The 3D-MMI enabled adequate spatial visualization of the ICA, CS and tumors. All patients were operated on under the guidance of ION with 3D-MMI. Conclusion  Classification based on 3D-MMI can better demonstrate the relationships among tumor, ICA and CS in a stereo and multi-angle view, which will have significance in guiding the surgical strategy.

Anatomical Basis of Clinical Manifestations Seen in Cavernous Sinus Syndrome: A Narrative Review

Pathology involving the Cavernous Sinus (CS), generally referred to as Cavernous Sinus Syndrome (CSS), can arise from vascular disorders, neoplasms, infections, and non-infectious inflammatory disorders. An acute understanding of the CS and its regional anatomical structures is therefore pertinent in expounding the highly variable clinical manifestations seen in CSS as well as laying the groundwork for surgical intervention. Though the neuroanatomy of the cavernous sinus has been substantially chronicled in literature, their correlation to clinical signs has only been minimally described. This narrative review serves to address this knowledge gap and aims to comprehensively correlate the clinical manifestations of CSS with the relevant neuroanatomy, thereby allowing medical practitioners to better navigate the diagnostic quandary. We conducted a scoping review of the literature concerning CS anatomy and CSS, complied through MEDLINE/OVID and cross-referencing of articles on PubMed and Google Scholar with the keywords cavernous sinus, cavernous sinus syndrome, clinical signs/manifestations, neuroanatomy, CS pathology, Cavernous Sinus Thrombus (CST) and cavernous sinus neoplasms/tumours.

Overview of Neurotrophic Keratopathy and a Stage-Based Approach to Its Management

ABSTRACT

Neurotrophic keratopathy (NK) occurs because of disruption of corneal sensory innervation. There are many etiologies that can lead to NK, such as infection, trauma, topical medication use, cornea surgery, and intracranial tumors among others. We review the current available treatment options and provide a stage-based approach to its management.

Primary marginal zone B-cell lymphoma of the cavernous sinus: a case report and review of the literature

Background

Primary lymphoma of the cavernous sinus is a rare form of extranodal non-Hodgkin lymphoma, of which very few cases have been reported in the published literature. This report presents the MRI findings with apparent diffusion coefficient (ADC) value in an exceedingly rare primary marginal zone B-cell lymphoma (MZBCL) of the cavernous sinus.

Case presentation

The case in this study is a 59-year-old immunocompetent male patient with a 2-month history of right ptosis and blurred vision. Right third cranial nerve palsy and binocular diplopia were observed upon neurological examination. Preoperative brain CT showed an extra-axial enhancing mass lesion in the right cavernous sinus. On MRI, ipsilateral internal carotid arterial encasement was noted without causing stenosis of the vessel. Isointense signal on T1-weighted and T2-weighted images, homogeneous contrast enhancement, and diffusion restriction were also observed. The mean ADC value of the tumor is 0.64 × 10^–3 mm²/s (b value = 1000 s/mm²). Subtotal resection of the tumor was performed, and improvement of clinical symptoms were observed. The pathologic diagnosis of MZBCL was established by immunohistochemical examinations.

Conclusions

Primary MZBCL of the cavernous sinus is exceedingly rare, and preoperative confirmation poses a major challenge with CT and conventional MRI only. In this case, preoperative quantitative ADC value is shown to offer valuable additional information in the diagnostic process.

Septic cavernous sinus thrombosis-Case series and review of the literature

BACKGROUND AND PURPOSE

Septic cavernous sinus thrombosis (CST) is a rare, life-threatening disease with infectious thrombosis causing associated complications resulting in high morbidity and mortality. We report a series of CST patients with assessment of arterial and intracranial complications.

METHODS

We used the radiology database from a large, academic tertiary care center to collect all patients treated with CST between 2002 and 2019. Patient demographics, source of infection, treatment course and outcomes were evaluated. A review of the recent literature was also performed for similar reported complications from CST.

RESULTS

14 patients with CST treated during this time period were assessed. Of the 14 patients, 1 patient died. 7 patients had unilateral narrowing of ICA while 3 patients had bilateral narrowing. The ICA narrowing was reversible in 10/12 patients and improvement but persistent narrowing in one patient. One patient had an infectious pseudo aneurysm that was treated by coiling. Extension of thrombosis to the transverse- sigmoid sinuses and internal jugular vein were seen in 3 patients. Three patients had subdural empyema which was treated surgically.

CONCLUSION

The prognosis of CST has improved with advancement in treatment, but complications are not infrequent.

Sphenoid dural arteriovenous fistulas

Sphenoid wing dural AVFs represent a rare clinical entity. These lesions may be asymptomatic or present with focal neurologic deficits, intracranial venous hypertension, or intracranial hemorrhage. Diagnosis is based on clinical findings and diagnostic imaging. They are alternatively classified as lesions of either the greater or lesser wings of the sphenoid bone. We performed a search of the PubMed database of studies evaluating the clinical behavior and surgical and endovascular therapies of these lesions. Dural AVFs draining into the superficial middle cerebral vein and/or laterocavernous sinus, or rather, lesions of the greater wing of the sphenoid, exhibit a greater likelihood of developing an aggressive clinical course, with higher probability of cortical venous reflux and consequent intracranial venous hypertension, intracranial hemorrhage, and symptomatic presentation. Dural AVFs of the sphenoparietal sinus, that is, lesions of the lesser wing of the sphenoid, typically exhibit a more benign clinical course, as there is a prominent epidural venous drainage into the cavernous sinus, reducing the risk of cortical venous reflux, and consequently, the probability of intracranial venous hypertension, hemorrhage, and floridly symptomatic presentation. These lesions may be treated via surgical clipping of the fistulous point, transarterial or transvenous embolization, and/or stereotactic radiosurgery. Though surgical intervention was the principal therapy due to facility of craniotomy access to the fistulous point, embolization has become standard of care permitted by innovation in endovascular technology. The natural history, clinical presentation, angioarchitecture, diagnosis, and management of these lesions are reviewed and discussed.

Double pituitary adenomas associated with persistent trigeminal artery: a rare case report and the review of literature

Multiple pituitary adenomas are rare. We present a quite unique case of double pituitary adenomas associated with persistent trigeminal artery (PTA) treated by endoscopic surgery. To the best of our knowledge, this is the first report in the literature. A 64-year-old woman was referred to our hospital for suspicion of acromegaly. Preoperative magnetic resonance imaging revealed two separate intrasellar masses with intrasellar vascular structure. Right cerebral angiography showed medial-type PTA. The patient underwent endoscopic transsphenoidal surgery and both tumors were resected completely. Postoperative immunohistopathologic examination revealed two histologic types of adenoma: the first tumor was positive for growth hormone (GH), while the second was considered nonfunctioning. Postoperatively, the patient's serum levels of GH and insulin-like growth factor-1 returned to normal. We observed an extremely rare case of double pituitary adenomas associated with PTA. Preoperative neuroimaging and modern endoscopic surgery are valuable to confirm diagnosis of double pituitary adenomas and identify anatomical localization of PTA.

A singular case of cavernous internal carotid artery aneurysm in patient with cavernous sinus syndrome and bacterial meningitis

We report the uncommon case of an acute cavernous sinus syndrome in a patient who was consequently discovered to have both a cavernous internal carotid artery aneurysm and bacterial meningitis. Which came first, the chicken or the egg? Which of the two, the aneurysm or the meningitis, gave rise to the patient’s symptoms? We briefly reviewed the literature of similar cases and tried to analyze the possible pathophysiological relationship between these findings. Moreover, this case highlights the importance of a multidisciplinary management of these patients to better decide between a medical and a surgical and/or endovascular treatment.

Prognostic Value of Cavernous Sinus Invasion in Patients with Nasopharyngeal Carcinoma Treated with Intensity-Modulated Radiotherapy

Purpose

To investigate the prognostic value of cavernoussinus invasion (CSI) in patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT).

Patients and Methods

Retrospective review of data from 1,087 patients with biopsy-proven, non-metastatic NPC. All patients were diagnosed using magnetic resonance imaging (MRI) scans and received IMRT as the primary treatment.

Results

The incidence of cavernoussinus invasion in this cohort was 12.1%. In univariate analysis, 5-year overall survival (OS) (70.6% vs. 88.5%, P < 0.001) and distant metastasis-free survival (DMFS) (71.4% vs. 87.7%, P < 0.001), but not locoregional relapse-free survival (LRFS) (93.9% vs. 93.7%, P = 0.341), were significantly different between patients with and without cavernoussinus invasion. In the T4 subgroup, the 5-year OS, DMFS, and LRFS of patients with and without cavernoussinus extension were 70.6% vs. 81.9% (P = 0.011), 71.4% vs. 84.1% (P = 0.011), and 91.2% vs. 89.7% (P = 0.501), respectively. In multivariate analysis, cavernoussinus invasion was an independent prognostic factor for poorer OS (HR = 1.782; P = 0.013) and DMFS (HR = 1.771; P = 0.016), but not LRFS (HR = 0.632; P = 0.294). In patients with lymph node metastasis, the DMFS rates of patients with and without cavernoussinus invasion were significantly different (P < 0.001). Preliminaryanalysis indicated that neoadjuvant chemotherapy led to better DMFS and OS in patients with cavernoussinus invasion than concurrent chemotherapy or radiotherapy alone; however, the differences were not significant.

Conclusions

In the IMRT era, cavernoussinus invasion remains a prognostic factor for poor DMFS and OS in NPC, even in patients with T4 disease.