G. Pero

Bilateral Congenital Absence of Internal Carotid Arteries in a Woman with Dementia A Case Report

Dysgenesis of THE internal carotid artery is considered a rare condition, present in about 0.01% of subjects. This anomaly is generally asymptomatic and often represents an incidental finding in radiological examinations of the head performed for other reasons. A 75-year-old woman with symptoms of dementia was admitted to our hospital. Computed tomography and magnetic resonance examinations were performed. They showed the absence of both internal carotid arteries and the congenital nature of this abnormality. The usefulness of CT and MRI examinations in patients with this vascular abnormality is discussed.

Spontaneous Temporal Cerebrospinal Fluid Leak: A Case Report and Literature Review

An abnormal communication between the subarachnoid spaces and the tympanic cavity and mastoid cells can determine a cerebrospinal fluid (CSF) leak in the air spaces of the temporal bone. The etiology of CFS leak in the temporal air cells includes acquired, congenital and spontaneous causes. Spontaneous CSF leak, defined as a leak without a manifest cause, is present in about 4% of cases and often occurs in the middle cranial fossa. We describe a case of spontaneous CSF leak in the right temporal air cells that mimicked a skull fracture in a subject with headache and apparent rhinorrhea after a head trauma. Both CT and MRI play a key role in the differential diagnosis between post-traumatic temporal CSF leak due to a fracture and spontaneous leak: traumatic CSF leak often does not require a surgical approach, whereas spontaneous CSF leak may need surgical treatment because of the risk of meningitis.

Osteoblastoma of the Orbit: A Case Report and Review of the Literature

We describe a case of benign orbital tumour involving the frontal sinus and ethmoidal cells. CT findings were typical of “bone tumour of the orbit”, histological analysis yielded a diagnosis of benign osteoblastoma. A review of the literature disclosed only 13 well documented cases. We compared out radiological findings with the features described in these reports. CT patterns were similar in most cases. The lesion generally appears as a heterogeneous mass where it is possible to appreciate both high density portions and low density areas. On MRI osteoblastoma shows an iso- low signal both in T1 and in T2 sequences. Less frequently the lesion may yield a high signal in T2 images. The orbit is rarely involved by bone tumours, but all bone tumours may theoretically involve the orbit, often making it difficult to establish the right differential diagnosis by imaging. Thirteen cases are insufficient to describe general radiological criteria to improve the specificity in detection of this disease and a broader outlook is essential. For this reason we also examined the radiological signs of bone tumours involving other portions of the body. Even though many literature reports suggest CT is the landmark in bone tumour diagnosis, we think it should always be accompanied by MRI. MRI is known to overestimate local staging, but its contribution to differential diagnosis among various tumours may be decisive.

Imaging of Rathke's Cleft Cysts: Criteria for a Differential Diagnosis

Rathkes cleft cysts are a congenital disorder of the pituitary gland and derive from abnormalities of the development of the adenohypophisis. The variability of the MRI signal of Rathkes cleft cyst hampers the differential diagnosis with the other cystic lesions of the pituitary gland. Nevertheless a comparison between the various findings reported from by author we reviewed indicates that a description of useful criteria for a differential diagnosis is possible. We suggest that the mean age at onset, the symptoms, the magnetic signal intensity, the location within the gland, the relations with the surrounding structures and the behaviour after contrast injection should always be considered in the diagnostic work-up of Rathke s cleft cysts. There is no consensus in the literature on the correct therapeutic protocol. We suggest following up a small asymptomatic Rathkes cleft cyst (except mucoid cysts) because they do not generally enlarge. Surgery is instead the gold standard for symptomatic Rathkes cleft cysts, large Rathkes cleft cysts and mucoid Rathkes cleft cysts. Mucoid Rathkes cleft cysts, even when small, may cause an intense pituitary inflammation which could lead to irreversible endocrine dysfunction.

Carotid Body Paraganglioma. Diagnosis and Treatment by Angiography

Paraganglioma is a rare neoplasia of neural crest origin. It most commonly arises in carotid body, jugular bulb, tympanic plexus on the promontory, and along the vagal nerve pathway or anywhere along the paraganglia pathway. This review describes our experience of cervical paraganglioma. Although there is no consensus in the literature on preoperative angiographic embolization, we think angiography is the gold standard in the diagnosis and treatment of paraganglioma. A small paraganglioma probably does not usually require preoperative embolization because the risks may exceed the benefits. But angiography is mandatory in the diagnosis and treatment of large highly vascular paragangliomas. Imaging of the vascular map of the tumor, that is only possible by angiography, will help the neurosurgeon evaluate the real extension of the neoplasia and chose treatment modalities. Embolization is performed to decrease operative bleeding, shorten the surgery timing and avoid cranial nerve deficit. Cemal Umit Isik et al. studied four brothers with familial paragangliomas noting unexplained concomitant thyroid functional disorders in their patients. Because of the pedigree they thought this may have been a coincidence. Our reported case, unrelated to the Turkish family, also had hypothyroidism suggesting that the relation between paraganglioma and thyroid dysfunction may not be merely a coincidence.

Hemifacial Spasms and Involuntary Facial Movements. Role of Magnetic Resonance in the Diagnostic Work-up. A Case Report.

Caution is required when dealing with patients presenting hemifacial spasm as the symptom is common to many disorders (tumours, herpes zoster, a frigore paralysis, neurovascular conflict…). Often no reasonable cause of the spasm is found, but treatment must be attempted because hemifacial spasm can be highly debilitating. We describe a case of hemifacial spasm, initially deemed idiopathic, in which MRI demonstrated neurovascular conflict as the cause. It is not always easy to find a clear MRI pattern, but if the scan identifies the tortuousness of the arteries in the vicinity of the VII nerve root exit, it is highly probable that this is the true cause of hemifacial spasm. Even when it is not possible to identify this pattern, neurovascular compression cannot be ruled out. The good results of microvascular decompression in patients without a typical MRI pattern suggest that MRI is specific, but not always sensitive. There is no consensus in the literature on the sensitivity of MRI in the detection of neurovascular compression and values vary widely. It is generally believed that experience and different performance of the MR systems strongly influence the diagnosis of neurovascular conflict.

MRI Aspects of Neuro-Vascular Conflict of the VIII Nerve.

The vascular cross compression syndrome of the vestibule-cochlear nerve is an abnormal contact between the VIII nerve and a vessel leading to tinnitus and/or vertigo due to the nerve irritation. MRI is an important diagnostic tool as it will display the whole course of the nerve and identify the site and the type of neuro-vascular contact. However, MR findings are not specific and diagnosis can only be made on the basis of clinical and otolaryngologic features, after ruling out other possible diseases causing the same symptomatology. We describe 15 patients with neuro-vascular conflict disclosed by MRI examination which was associated with non specific neuro-othologic symptoms.

Vertebral aggressive hemangioma. A case report and literature review.

Aggressive hemangiomas are rare and can compress the spinal cord, nerve roots or both, producing myelopathy or radiculopathy. This report describes an aggressive and compressive hemangioma of the body of the Th9 vertebra in a woman with symptoms of medullary sufferance, treated with embolization of the afferent vessels of the lesion followed by radiotherapy.

An Interpretation of Optic Nerve Tortuosity A Case Report

Magnetic resonance imaging disclosed both optic nerve tortuosity and kinking in a 64-year-old man with orbital pain and monolateral abducens nerve palsy. The association between optic nerve tortuosity and abducens nerve palsy is often described in literature reports of idiopathic intracranial hypertension. However the diagnosis of idiopathic intracranial hypertension was excluded in our patient because of the absence of other signs such as papilledema (universally present in the cases of idiopathic intracranial hypertension), visual loss, headache and flattening of the posterior sclera. Other possible diagnoses to be considered when looking at a case of optic nerve tortuosity are neurofibromatosis and/or optic nerve glioma. Tortuosity of both optic nerves seems to be isolated in our patient and not associated with other diseases or disorders. We suggest that in some patients optic nerve tortuosity could be correlated with an aberrant anatomical development of the optic nerve. Further studies are necessary to confirm this hypothesis which currently remains conjectural.

Advanced ossification of the posterior longitudinal ligament in a mildly symptomatic patient. A case report and literature review.

We describe the imaging findings of a man who developed neurologic symptoms due to ossification of the posterior longitudinal ligament with narrowing of the spinal canal and compression of the spinal cord. CT study allowed a detailed evaluation of the stenosis and the extension of the ossification while MRI gave an excellent visualization of the spinal lesions caused by spinal cord compression by the mass. The neurological status of patients with ossification of the posterior longitudinal ligament depends on many factors such as the degree of spinal canal stenosis, life style, accidental mechanical stress and trauma.