Central skull base osteomyelitis: a rare but life-threatening disease.

We present the case of a 70-year-old non-diabetic patient who presented to the emergency department with unrelenting otalgia. A severe otitis externa (OE) and mastoiditis were treated with broad spectrum antibiotics and surgical drainage. No bacteria was isolated from surgical samples. Because the otalgia persisted, a magnetic resonance (MR) was performed and showed an infiltrating process at the skull base. Biopsies failed to prove malignancy or granulomatosis. The patient's neurological state deteriorated. The suspicion of a skull base osteomyelitis (SBO) was raised and proven by CT-guided biopsies that grew Pseudomonas aeruginosa. Meropenem and ciprofloxacin, given for 8 weeks, lead to a fast clinical improvement and a full recovery. SBO is uncommon, often complicating severe OE. Pseudomonas aeruginosa is the main pathogen. Prompt diagnosis and adequate antibiotherapy are required to lower mortality and morbidity. The diagnosis may be delayed because of unawareness and large differential diagnosis including solid neoplasic tumours, malignant hemopathies and granulomatosis.

Trigeminal melanoma metastasis.

We present the case of a 70-year-old patient presented to our institution for paresthesia of the right hemiface associated with dysarthria in aggravation since 1 year. He was diagnosed with right trigeminal melanoma metastasis. This case is characterized by a thickening of the right trigeminal nerve from his cisternal segment to his mandibular branch V3. MRI demonstrated an intensive perineural spread by a melanotic melanoma.

Gliomatosis cerebri, imaging findings of 12 cases.

BACKGROUND AND PURPOSE: We report 12 cases of Gliomatosis cerebri (GC), a rare brain neoplasm, to define its semeiologic criteria. Literature was reviewed to clarify its physiopathology. PATIENTS AND METHODS: From 1997 to 2008, 12 histologically proven cases with GC were retrospectively reviewed. Of the 12 patients, nine were male. The mean age was of 54 years. Were performed CT-Scan (n=6), MRI (n=12), diffusion and perfusion weighted images (n=12 and n=4), MR Spectroscopy (n=3), a FDG and a Methionin PET-Scan (n=2 and n=3 respectively). RESULTS: Primary diagnosis was missed in six cases. Most frequent clinical signs were seizure and mental changes. Imaging criteria were: area of high signal intensity on FLAIR and T2-weighted images, involving three or more contiguous lobes with conserved architecture. Frequently a bilateral widespread invasion with involvment of the corpus callosum or the anterior white commissure or both was observed. At diagnosis and in the classical form (type I) of GC, no significant contrast enhancement and decreased rCBV were observed. Focal enhancement and increased rCBV were observed in the focal mass in type II GC. MR Spectroscopy showed an increase of the Cho/Cr ratio and a decrease in the NAA/Cr one. FDG PET showed in type I a decreased avidity for the FDG whereas in type II a increased avidity was observed. MET-PET showed an increased avidity for the tracer in a GC type II and a slight avidity in a GC type I. CONCLUSION: GC is a rare brain entity. Primary diagnosis is often missed. The imaging findings of GC I, a WHO grade III tumor, should be known and include classical MRI but also PWI, MRS and scintigraphic findings.

Segmental spinal myoclonus and syringomyelia: A case report.

We report the case of a 75-year-old woman who developed involuntary jerks of the abdominal musculature. They occurred spontaneously or triggered by a forced inspiration or attempts to rise from the supine position. Electromyography (EMG) recorded abnormal bursts of muscle activity in the abdominal, thoracic paraspinal, and intercostal muscles up to the 3rd intercostal space. The bursts were bilateral, arrythmic and synchronous in all muscles. Magnetic resonance imaging (MRI) of the spine revealed a syringomyelic cavity between the T3 and T10 levels. The topological correlation between the EMG muscle activities and the MRI findings was consistent with spinal myoclonus arising from the thoracic spinal cord. The synchronous bursts in muscles depending from few adjacent spinal segments suggested the diagnosis of segmental spinal myoclonus (SSM). There are few reports of SSM related to syringomyelia in the literature.

Discrepancy between diffusion and perfusion imaging in a patient with transient ischaemic attack.

We report paradoxical and ambiguous imaging findings in a patient with transient ischaemic attack (TIA). Perfusion-weighted (PW) MRI obtained 2 hours after symptoms onset showed a hypoperfused area in a region compatible with the focal deficit, while diffusion-weighted (DW) MRI was considered negative. Despite the complete resolution of the symptoms which had already begun at the end of the first MR examination, follow up DW MRI at 3 days showed partial conversion to hyperintensity of the initially hypoperfused area. This case illustrates that PW and DW MRI have to be used in combination and at different time points to correctly diagnose and manage ischaemic stroke because PW MRI is more sensitive than DW MRI for very early detection of ischaemia and delayed DW MRI provides the final signature of brain damage even in case of complete clinical recovering.

Unusual growth within a meningioma (leukemic infiltrate).

Intracranial meningiomas are generally slow-growing neoplasms. Symptoms depend on their critical intracranial location. The authors describe a case of rapidly enlarging meningioma that became symptomatic as a result of invasion by leukemic cells at the time of a blastic crisis in the context of chronic myeloid leukemia. Infiltration of an intracranial meningioma by cells from extracranial malignant neoplasms is a rare event. Even though central nervous system (CNS) or meningeal involvement is common in some hematologic malignancies, this is, to the best of our knowledge, the first report of invasion of an intracranial meningioma by leukemic cells.

Cervical epidural pseudotumor and multifocal fibrosclerosis. Case report and review of the literature.

The authors present the case of a 45-year-old man suffering from progressive quadriplegia due to an expansive C3-T2 epidural mass. Neuropathological examination demonstrated pseudotumor tissue. The patient had had an orbital pseudotumor 5 years before admission, and other systemic manifestations of an idiopathic inflammatory disease were discovered. This case is extremely rare. Nine cases of multifocal fibrosclerosis with central nervous system involvement are described in the literature. To the authors' knowledge, this is the first description of a cervical epidural pseudotumor. Modern imaging has made the diagnosis of such an entity possible, and it is important for the neurosurgeon to consider this syndrome because the combination of surgery and systemic medical therapy can ensure a long-term survival with good quality of life.

Hypoplasia of the internal carotid artery: a noninvasive diagnosis.

We present the characteristic imaging findings of hypoplasia of the internal carotid artery (ICA) in two cases, one accompanied by an intracranial aneurysm. Finding of a diffuse luminal narrowing of the ICA on MR angiography or digital subtraction angiography (DSA) could wrongly evoke severe acquired diseases such as dissection or atherosclerosis. Absence of associated wall thickening and flow disturbances on color Doppler sonography (CDS) should suggest carotid hypoplasia. Confirmation of the diagnosis is obtained by CT of the skull showing a small carotid canal. Non-invasive procedures are sufficient to differentiate this rare congenital anomaly from acquired string signs.

Axillary schwannoma masquerading as cervical radiculopathy.

A 58-year-old woman, suffering from radicular-like pain in the left arm for 3 years, presented an entirely negative cervical imaging. Careful clinical examination disclosed Tinel's sign in the axilla. This clinical finding led to further investigation of this region. Computed tomography and magnetic resonance imaging disclosed a small tumour highly suggestive of a schwannoma. Surgical exploration and microscopic examination confirmed a diagnosis of schwannoma located on the radial trunk of the left brachial plexus. After tumour excision, the patient had immediate relief of pain without sensitive or motor sequelae. No recurrence has been observed after 3 years.

An early MR observation of carotid involvement by retropharyngeal abscess.

We report early carotid involvement by retropharyngeal abscess in a 4-year-old boy. MR imaging showed enhancement of the wall and narrowing of the lumen of the internal carotid artery, which were thought to reflect spasm and/or arteritis. Prompt treatment may have prevented hemorrhagic and neurologic complications.

Unusual occipitoatlantal fracture dissociation with no neurological impairment. Case report.

The authors describe an unusual case of a complex traumatic fracture-dissociation injury of the craniovertebral junction, which the patient survived with no neurological damage. This case featured the rare combination of an avulsion of both the right occipital condyle and clivus and a fracture of the left lateral mass of the atlas. Because of the craniocervical ligament injury and the slight anterior occipitoatlantal dislocation, the lesion was considered to be unstable and was treated successfully with a cervical collar. The authors emphasize that thin-slice computerized tomography scanning with multiplanar reconstructions is essential to visualize these fractures, whereas magnetic resonance imaging is useful to assess soft tissues.

Hemorrhagic arachnoid cyst with third nerve paresis: CT and MR findings.

We report the CT and MR appearance of a nontraumatic hemorrhagic arachnoid cyst presenting with a third nerve paresis in a 37-year-old man. The cyst, located in the left suprasellar area, contained a fluid-blood level with stigmata of subacute hemorrhage on both CT and MR studies.

Castleman's disease in the neck: MRI.

We describe a case of Castleman's disease in a 8-year-old-boy who presented with a slowly growing mass in the upper neck. MRI showed a well-defined homogeneous mass with nonspecific signal features. Unusual features were a kidney-bean shape and the deep location in the suprahyoid region, the mass originating in the left retropharyngeal space.