Are bilateral cavernous hemangiomas of the orbit rare entities? The role of MRI in a retrospective study.

Cavernous hemangioma is a benign orbital extraocular vascular lesion consisting of large dilated venous channels with fibrous, well-delineated capsule and hemosiderin deposition. Cavernous hemangioma is considered to be almost always unilateral and bilateral cases have been rarely described. The aim of our study is to evaluate imaging characteristics of cavernous hemangioma and evaluate the prevalence of bilateral cases. We studied 14 patients with cavernous hemangioma of the orbit with surgical confirmation. MRI was performed on a 1.5-T unit before and after contrast agent administration. Each MR examination had been retrospectively evaluated in order to define signal patterns, dimensions, location and other main imaging characteristics. In 3 out of the 14 cases studied (21.4%) bilateral cavernous hemangiomas were found. Thirteen masses appeared isointense on T1, two were hypointense, and two heterogeneous. On T2, 12 were hyperintense, 3 were heterogeneous, 1 isointense, and 1 hypointense. Contrast enhancement was inhomogeneous in 5, homogeneous and intense in 12 cases. The size ranged from 3mm up to 21 mm (average 14.57). In four patients also CT scan without contrast administration of the orbits was performed. Bilateral cavernous hemangioma appears to be more frequent than as predicted by the literature. In our opinion the main reason of this incongruence is related to technological advances. Our results could also be related to carelessness of radiologists to inspect the other orbit for possible concomitant lesions, and thus invites to major attention in exploring both orbits for eventual bilateral lesions.

Degenerative disease of the spine.

Degenerative disease of the spine is a definition that includes a wide spectrum of degenerative abnormalities. Degeneration involves bony structures and the intervertebral disk, although many aspects of spine degeneration are strictly linked because the main common pathogenic factor is identified in chronic overload. During life the spine undergoes continuous changes as a response to physiologic axial load. These age-related changes are similar to pathologic degenerative changes and are a common asymptomatic finding in adults and elderly persons. A mild degree of degenerative changes is paraphysiologic and should be considered pathologic only if abnormalities determine symptoms. Imaging allows complete evaluation of static and dynamic factors related to degenerative disease of the spine and is useful in diagnosing the different aspects of spine degeneration.

Pediatric stroke: clinical findings and radiological approach.

This paper focuses on radiological approach in pediatric stroke including both ischemic stroke (Arterial Ischemic Stroke and Cerebral Sinovenous Thrombosis) and hemorrhagic stroke. Etiopathology and main clinical findings are examined as well. Magnetic Resonance Imaging could be considered as the first-choice diagnostic exam, offering a complete diagnostic set of information both in the discrimination between ischemic/hemorrhagic stroke and in the identification of underlying causes. In addition, Magnetic Resonance vascular techniques supply further information about cerebral arterial and venous circulation. Computed Tomography, for its limits and radiation exposure, should be used only when Magnetic Resonance is not available and on unstable patients.

Parry-Romberg syndrome and Rasmussen encephalitis: possible association. Clinical and neuroimaging features.

Parry-Romberg syndrome (PRS) is a sporadic disease of unknown etiology with typical onset in childhood or in young adults. It is characterized by a slow and progressive atrophy affecting one side of the face, the skin, the subcutaneous tissue, the muscles, the cartilages, and the underlying bony structures. The neurological symptoms usually include focal epilepsy, migraine, and unilateral brain lesions on the same side as the atrophy. A common neuroimaging finding of the syndrome is white matter high signal intensity on brain magnetic resonance (MR) imaging. Rasmussen encephalitis (RE) is a rare and chronic inflammatory disease of the brain that begins in the first decade of life and more rarely in adolescents and adults. It usually involves one hemisphere with focal cortical inflammation. Neurologic symptoms are intractable seizures and progressive hemiplegia. Both PRS and RE are often associated with other inflammatory or autoimmune disorders and only 1 case of both syndromes has been reported in literature. We report the clinical and neuroradiological findings in a 6-year-old boy, presenting with focal hemifacial and arm motor seizures and progressive facial hemiatrophy. Serial MR imaging studies revealed progressive brain hemispheric signal alterations and atrophy. This would thus suggest acoexistence of PRS and RE.

Radiological strategy in acute stroke in children.

The aim of the study was to estimate the preponderance of patterns of pediatric stroke, ischemic or hemorrhagic, their etiologies and the correct diagnostic protocol for acute management. Forty-one consecutive pediatric patients (age range 5-16 years) with an acute stroke observed in acute phase during a 10-year period, were retrospectively evaluated. Twenty-three patients underwent magnetic resonance imaging (MRI), 3 cases were studied by computed tomography (CT) without MRI, and 15 underwent both CT and MRI studies. In 9 cases, intra-arterial digital subtraction angiography (IADSA) was performed after non-invasive preliminary assessment. Seventeen hemorrhagic (41%) and 24 ischemic (59%) strokes were found. Among hemorrhagic forms, 5 cases were due to arteriovenous malformation (AVM), 7 to cavernoma, and 2 to aneurysm. Among ischemic forms, 2 were due to sickle-cell disease, 1 to hyperomocysteinemia, 1 to moyamoya syndrome, 1 to pseudoxantoma elasticum, 3 to prothrombotic state, 1 to Fabry's disease, 1 concomitant with CO intoxication, 5 to venous sinus thrombosis, and 4 to cardio-embolic state. Etiology remains unknown in 8 cases (20.5%). This study shows a moderate prevalence of ischemic over hemorrhagic strokes. Moreover, personal experience suggests that MRI is always more informative than CT and in selected cases should be the first-choice examination in the acute phase.

Reversible focal splenial lesions.

Reversible focal lesions in the splenium of the corpus callosum (SCC) have recently been reported. They are circumscribed and located in the median aspect of the SCC. On MRI, they are hyperintense on T2-W and iso-hypointense on T1-W sequences, with no contrast enhancement. On DWI, SCC lesions are hyperintense with low ADC values, reflecting restricted diffusion due to cytotoxic edema. The common element is the disappearance of imaging abnormalities with time, including normalization of DWI. Clinical improvement is often reported. The most established and frequent causes of reversible focal lesions of the SCC are viral encephalitis, antiepileptic drug toxicity/withdrawal and hypoglycemic encephalopathy. Many other causes have been reported, including traumatic axonal injury. The similar clinical and imaging features suggest a common mechanism induced by different pathological events leading to the same results. Edema and diffusion restriction in focal reversible lesions of the SCC have been attributed to excitotoxic mechanisms that can result from different mechanisms; no unifying relationship has been found to explain all the pathologies associated with SCC lesions. In our opinion, the similar imaging, clinical and prognostic aspects of these lesions depend on a high vulnerability of the SCC to excitotoxic edema and are less dependent on the underlying pathology. In this review, the relevant literature concerning reversible focal lesions in the SCC is analyzed and hypotheses about their pathogenesis are proposed.

Pituitary macroadenomas: preoperative evaluation of consistency with diffusion-weighted MR imaging--initial experience.

PURPOSE: To prospectively evaluate use of diffusion-weighted (DW) magnetic resonance (MR) images and apparent diffusion coefficient (ADC) maps for determination of the consistency of macroadenomas. MATERIALS AND METHODS: The study protocol was approved by the institutional ethics committee, and informed consent was obtained from all patients. Twenty-two patients with pituitary macroadenoma (10 men, 12 women; mean age, 54 years +/- 17.09 [standard deviation]; range, 21-75 years) were examined. All patients underwent MR examination, which included T1-weighted spin-echo and T2-weighted turbo spin-echo DW imaging with ADC mapping and contrast material-enhanced T1-weighted spin-echo imaging. Regions of interest (ROIs) were drawn in the macroadenomas and in normal white matter on DW images, ADC maps, and conventional MR images. Consistency of macroadenomas was evaluated at surgery and was classified as soft, intermediate, or hard. Histologic examination was performed on surgical specimens of macroadenomas. Mean ADC values, signal intensity (SI) ratios of tumor to white matter within ROIs on conventional and DW MR images, and degree of enhancement were compared with tumor consistency and with percentage of collagen content at histologic examination by using analysis of variance for linear trend. RESULTS: The mean value of ADC in the soft group was (0.663 +/- 0.109) x 10(-3) mm(2)/sec; in the intermediate group, (0.842 +/- 0.081) x 10(-3) mm(2)/sec; and in the hard group, (1.363 +/- 0.259) x 10(-3) mm(2)/sec. Statistical analysis revealed a significant correlation between tumor consistency and ADC values, DW image SI ratios, T2-weighted image SI ratios, and percentage of collagen content (P < .001, analysis of variance). No other statistically significant correlations were found. CONCLUSION: Findings in this study suggest that DW MR images with ADC maps can provide information about the consistency of macroadenomas.

High-resolution and color doppler sonography in the evaluation of skin metastases.

OBJECTIVE: To evaluate high-resolution sonography in differentiating cutaneous metastases from other benign dermatologic diseases with the final objective of proposing high-resolution sonography in the diagnostic protocol for asymptomatic patients and those with neoplasms who have 1 or more rapidly growing skin nodules. METHODS: We selected 57 patients (24 women and 33 men; mean age +/- SD, 53 +/- 25 years) who underwent high-resolution and color Doppler sonography because they recently noticed 1 or more superficial nodules. Patients were mostly asymptomatic, but 15 had previously diagnosed malignancies. Each nodule was classified by measurement of fundamental sonographic parameters (major diameter, shape, borders, echo texture, and homogeneity) and by assessment of vascularity (presence or absence of flow and vascular pattern) with color Doppler sonography. All nodules were ablated and histologically examined. RESULTS: Of 68 nodules, 23 were malignant (21 metastases and 2 B-cell lymphomas), and 45 were benign (22 sebaceous cysts, 18 granulomas of different origins, 3 fibromas, and 2 neurofibromas). The nodules were all localized in the subcutaneous space, had clearly demarcated borders, and were hypoechoic; a circular or oval shape was predominant, but 7 metastases had an irregular, polycyclic shape. On color Doppler sonography, none of the benign nodules or B-cell lymphomas showed signs of vascularity, whereas the metastatic nodules were all vascularized, with 1 or more peripheral poles (21 of 21 nodules) and internal vessels (11 of 21 nodules). CONCLUSIONS: A polycyclic shape and hypervascularity, with multiple peripheral poles and, eventually, internal vessels, should be considered the most indicative signs of metastasis.