Carotid cavernous aneurysm presenting as pituitary apoplexy

Imaging Errors in Distinguishing Pituitary Adenomas From Other Sellar Lesions

BACKGROUND

Pituitary adenomas and nonadenomatous lesions in the sellar region may be difficult to distinguish by imaging yet that distinction is critical in guiding management. The nature of the diagnostic errors in this setting has not been well documented.

METHODS

Two neurosurgeons and 2 neuroradiologists of differing experience levels viewed deidentified MRIs of 18 nonadenomatous sellar lesions and 21 adenomas. They recorded their diagnoses, the imaging features they used to make those diagnoses, and their confidence in making those diagnoses.

RESULTS

Among the 18 nonadenoma cases, 11 (61%) were incorrectly diagnosed as adenoma by at least 1 reader, including Rathke cleft cyst, plasmacytoma, aneurysm, craniopharyngioma, chordoma, Langerhans cell histiocytosis, metastasis, and undifferentiated sinonasal carcinoma. Among the 21 adenoma cases, 8 (38%) were incorrectly diagnosed by at least 1 reader as craniopharyngioma, Rathke cleft cyst, sinonasal carcinoma, hemangioblastoma, and pituitary hyperplasia. Incorrect imaging diagnoses were made with high confidence in 13% of readings. Avoidable errors among the nonadenomatous cases occurred when readers failed to appreciate that the lesion was separate from the pituitary gland. Unavoidable errors in those cases occurred when the lesions were so large that the pituitary gland had been obliterated or the imaging features of a nonadenomatous lesion resembled those of a cystic pituitary adenoma. Avoidable errors in misdiagnosis of adenomas as nonadenomas occurred when readers failed to appreciate features highly characteristic of adenomas. An unavoidable error occurred because a cystic adenoma had features correctly associated with craniopharyngioma.

CONCLUSIONS

Errors in imaging differentiation of pituitary adenoma from nonadenomatous lesions occurred often and sometimes with high confidence among a small sample of neurosurgeons and neuroradiologists. In the misdiagnosis of nonadenomatous lesions as adenomas, errors occurred largely from failure to appreciate a separate pituitary gland, but unavoidable errors occurred when large lesions had obliterated this distinguishing feature. In the misdiagnosis of adenomas as nonadenomatous lesions, avoidable errors occurred because readers failed to recognize imaging features more characteristic of adenomas and because cystic adenomas share features with craniopharyngiomas and Rathke cleft cysts. Awareness of these errors should lead to improved management of sellar lesions.

Cerebral aneurysms with intrasellar extension: a systematic review of clinical, anatomical, and treatment characteristics

Object

Intrasellar aneurysms are rare lesions that often mimic pituitary tumors, potentially resulting in catastrophic outcomes if they are not appropriately recognized. The authors aimed to characterize the clinical and anatomical details of this poorly defined entity in the modern era of neuroimaging and open/endovascular neurosurgery.

Methods

A PubMed literature review was conducted to identify all studies reporting noniatrogenic aneurysms with intrasellar extension, as confirmed by CT or MR imaging and angiography. Clinical, anatomical, and treatment characteristics were analyzed.

Results

Thirty-one studies reporting 40 cases of intrasellar aneurysms were identified. Six patients (15%) presented with aneurysmal rupture. Patients with unruptured aneurysms presented with the following signs and symptoms: headache (61%), visual field cuts/decreased visual acuity (61%), endocrinopathy (57%), symptomatic hyponatremia (21%), and cranial nerve paresis (other than optic nerve) (18%). The most common endocrine abnormalities were hyperprolactinemia and hypogonadism. Eight aneurysms (20%) were diagnosed in conjunction with a pituitary adenoma. Aneurysms could be categorized into 2 primary anatomical groups as follows: 1) cavernous/clinoid segment internal carotid artery (ICA) (infradiaphragmatic) aneurysms with medial extension into the sella; and 2) suprasellar (supradiaphragmatic) aneurysms originating from the ophthalmic segment of the ICA or from the anterior communicating artery, with inferomedial extension into the sella. The mean diameters of infradiaphragmatic and supradiaphragmatic aneurysms were 14.5 and 21.8 mm, respectively. Infradiaphragmatic aneurysms were much more likely to present with endocrinopathy, whereas supradiaphragmatic ones presented more commonly with visual disturbances. Aneurysms with infradiaphragmatic growth were generally treated using either endovascular techniques or surgical trapping and bypass, while supradiaphragmatic aneurysms were more often treated by surgical clipping.

Conclusions

Aneurysms with intrasellar extension typically present due to mass effect on surrounding structures, and they can be classified as infradiaphragmatic cavernous or clinoid segment ICA aneurysms, or supradiaphragmatic ophthalmic ICA or anterior communicating artery aneurysms. Varying approaches exist for treating these complex aneurysms, and intervention strategies depend substantially on the anatomical subtype.

Posterior communicating artery aneurysm rupture mimicking apoplexy

Background:

Cerebral aneurysm rupture can lead to devastating neurological complications and present a complex problem to treat. We report a unique case of a ruptured posterior communicating artery (PCoA) aneurysm presenting with sudden and complete vision loss.

Case Description:

A 39-year-old man presented with the acute onset of severe headache and complete bilateral vision loss. The patient described headaches for several months prior to presentation. However, prior to the day of presentation, he had no visual disturbance. A CT angiogram (CTA) and magnetic resonance imaging (MRI) of the brain revealed a 1.6-cm, non-contrast enhancing suprasellar mass, eccentric to the left side, consistent with hemorrhagic mass. There was no obvious aneurysm or vascular malformation. The sella tursica was normal in appearance. The patient was taken for an immediate endoscopic endonasal transtuberculum approach for optic nerve decompression. Hematoma without an associated tumor was encountered and partially evacuated before aborting with resultant partial improvement in vision. A subsequent cerebral angiogram revealed an irregularly shaped, postero-laterally pointing, 2.5-mm left PCoA aneurysm. The patient was then taken for open clipping of the ruptured aneurysm. A large, fibrinous capsule was found over the superolateral aspect of the aneurysm. The ruptured aneurysm was secured with clips and the surrounding hematoma was evacuated.

Conclusion:

In the immediate postoperative period, the patient regained vision in the nasal field of his right eye. This case illustrates a unique presentation of a ruptured PCoA aneurysm, and thus must be considered in the differential diagnosis of a suprasellar hemorrhage resulting in visual loss in absence of a recognizable associated tumor.

Overview of vascular complications of pituitary surgery with special emphasis on unexpected abnormality

Arterial bleeding during transsphenoidal surgery for pituitary adenoma is known complication. This usually happens due to rupture of intracavernous carotid or delayed hemorrhage due to the carotico-cavernous fistula and/or pseudoaneurysm. There is also evidence that cavernous carotid aneurysms may occur with pituitary tumors, yet largest series failed to demonstrate any link between aneurysm formation and pituitary tumors. Usually such an aneurysm rupture results in formation of carotico-cavernous fistula. However, pituitary apoplexy and even epistaxis have been reported. In this paper we present a patient with recurrent pituitary adenoma and cavernous carotid artery aneurysm, which caused significant hemorrhage during the surgery. Although retrospective analysis of MRI disclosed that the patient had the aneurysm before the first surgery, it remained silent until the second operation. Therefore neurosurgeons should be very susceptive to any signal changes on preoperative MR images, especially in recurrent cases, where normal anatomical relations are disturbed by fibrotic tissue. Also, we reviewed the vascular complication of pituitary surgery based on the literature.

Pituitary apoplexy: an overview of 186 cases published during the last century

BACKGROUND

Pituitary apoplexy is a rare and life-threatening complication occurring in 0.6-10.5% of all cases of pituitary adenomas. Although the association between pituitary apoplexy and visual dysfunction has been recognized for a long time, the optimal management of this problem still remains controversial. The purpose of this overview was to present the surgical experience by analyzing the literature on the management of pituitary apoplexy for better treatment of these cases.

MATERIALS AND METHOD

To establish a new guideline for the surgical treatment of this entity, publications reported during the last century and databases containing medical literature were analyzed. In addition, an illustrative case with pituitary apoplexy presenting with complaints of sudden onset severe headache associated with nausea, vomiting, and a sudden loss of vision was described. In fact, the experience in our complicated patient prompted us to review the available literature on the management of pituitary apoplexy to date.

CONCLUSIONS

Based on an overview of 186 cases of apoplectic pituitary adenoma presenting with monocular or binocular blindness, we highlight the importance of correct diagnosis and an early, but not necessarily emergency, surgery within the first week of admission to optimize visual outcome of such patients. The illustrative case further exemplifies the value of close interaction between members of the management team for optimal outcome.

Headache attributed to arteritis, cerebral venous thrombosis, and other vascular intracranial disturbances

Headache with variable characteristics and associated signs and symptoms may occur in all forms of arteritis. Giant cell arteritis, one of the most common forms, involves branches of the external and, more rarely, of the internal carotid arteries. It occurs in patients over the age of 50 and is characterized by fever, new-onset headache, prominence and tenderness of the temporal artery, claudication of the masticatory muscles on chewing, amaurosis fugax, and visual loss. Headache is the initial symptom in 48% of patients and is present in 90%. Primary central nervous system angiitis is a rare and highly fatal disease in which headache is one of the most frequent symptoms despite the fact that, given its non-specific characteristics, it is of little diagnostic relevance. Headache may also be attributed to several secondary central nervous system arteritides such as Behçet's disease, Takayasu disease, polyarteritis nodosa, Kawasaki disease, Wegener's granulomatosis, systemic lupus erythematosus, and vasculitits caused by viruses, bacteria, fungi, rickettsiae, and protozoa. Thrombosis of the cerebral veins and sinuses is a distinct cerebrovascular disorder that, unlike arterial stroke, most often affects young adults and children. Headache is the most frequent but least specific symptom of venous sinus thrombosis, being present in more than 90% of patients. Headache can also be attributed to other vascular intracranial disorders such as cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), benign (or reversible) angiopathy of the central nervous system, and pituitary apoplexy.

Severe hyperprolactinemia associated with internal carotid artery aneurysm: differential diagnosis between prolactinoma and hypothalamic-pituitary disconnection

Sellar and parasellar masses blocking inhibitory hypothalamic dopaminergic tonus can produce hyperprolactinemia. One of these conditions, seldom reported, is internal carotid artery aneurysm causing pituitary stalk compression and hyperprolactinemia, the majority of which is related to small increases in serum prolactin levels. The aim of this study is to report the case of a patient with an internal carotid aneurysm and severe hiperprolactinemia. A 72 years old female patient, on oncology follow-up for clinically controlled cervical carcinoma, was evaluated due to worsening chronic headaches. During the investigation, computed tomography and magnetic resonance imaging (MRI) showed a sellar mass associated with high prolactin level (1.403 µg/L) that initially was considered a macroprolactinoma, and treated with bromocriptine. However, subsequent pituitary MRI suggested an internal carotid aneurysm, which was confirmed by an angioresonance imaging of cerebral vessels. On low bromocriptine dose (1.25 mg/day), there was a prompt normalization of prolactin levels with a great increase (> 600 µg/L) after withdrawal, which was confirmed several times, suggesting HPD. We report a patient with internal carotid artery aneurysm with severe hyperprolactinemia never reported before in patients with HPD, and the need for a differential diagnosis with macroprolactinomas even considering high prolactin levels.

Intracranial intrasellar kissing carotid arteries: case report

Intracranial "kissing" carotid arteries are a rare variant of the carotid arteries, where both internal carotid arteries deviate medially and touch each other near the midline within the sphenoid sinus or the sphenoid bone, including the sella. This anomaly is particularly important since it may cause or mimic pituitary disease and also may complicate transsphenoidal surgery. We report a rare case of intracranial intrasellar kissing carotid arteries in a 57-years-old woman that was submitted to a computed tomography angiography during investigation of a sudden headache, and to discuss the clinical relevance of this radiological finding.

Assessment of hemorrhage in pituitary macroadenoma by T2*-weighted gradient-echo MR imaging

BACKGROUND AND PURPOSE

Intratumoral hemorrhage occurs frequently in pituitary macroadenoma and manifests as pituitary apoplexy and recent or old silent hemorrhage. T2*-weighted gradient-echo (GE) MR imaging is the most sensitive sequence for the detection of acute and old intracranial hemorrhage. T2*-weighted GE MR imaging was used to investigate intratumoral hemorrhage in pituitary macroadenomas.

MATERIALS AND METHODS

Twenty-five consecutive patients who underwent total or subtotal resection of pituitary macroadenoma with heights from 17 to 53 mm, including 1 patient with classic pituitary apoplexy, underwent MR imaging before surgery, including T2*-weighted GE MR imaging. For histologic assessment of the hemorrhage in whole surgical specimens, we used hematoxylin-eosin staining.

RESULTS

T2*-weighted GE MR imaging detected various types of dark lesions, such as "rim," "mass," "spot," and "diffuse" and combinations, indicating clinical and subclinical intratumoral hemorrhage in 12 of the 25 patients. The presence of intratumoral dark lesions on T2*-weighted GE MR imaging correlated significantly with the hemorrhagic findings on T1- and T2-weighted MR imaging (P < .02 and <.01, respectively), and the surgical and histologic hemorrhagic findings (P < .001 and <.001, respectively).

CONCLUSION

T2*-weighted GE MR imaging could detect intratumoral hemorrhage in pituitary adenomas as various dark appearances. Therefore, this technique might be useful for the assessment of recent and old intratumoral hemorrhagic events in patients with pituitary macroadenomas.