Potenzialità delle sequenze fat suppression e del gadolinio nello studio RM della patologia degenerativa lombare

Le lombalgie e lombosciatalgie risultano estremamente frequenti nella popolazione. Il dolore viene attribuito solitamente alla patologia degenerativa discale, particolarmente alle ernie discali, ma le strutture della colonna potenzialmente in grado di determinare dolore sono numerose: dischi, osso, tendini, legamenti, faccette articolari, muscoli.

L'esame RM deve pertanto valutare con attenzione non soltanto il complesso somato-discale, ma anche gli elementi posteriori della colonna. Le sequenze T2 Fat-suppressed ed eventualmente T1 Fat-suppressed dopo somministrazione di mdc, nella nostra esperienza risultano di elevata capacità diagnostica nella patologia degenerativa della colonna, in particolare nel caso in cui l'esame RM convenzionale non mostri una chiara causa del dolore.

Spinal pain

The spinal pain, and expecially the low back pain (LBP), represents the second cause for a medical consultation in primary care setting and a leading cause of disability worldwide [1]. LBP is more often idiopathic. It has as most frequent cause the internal disc disruption (IDD) and is referred to as discogenic pain. IDD refers to annular fissures, disc collapse and mechanical failure, with no significant modification of external disc shape, with or without endplates changes. IDD is described as a separate clinical entity in respect to disc herniation, segmental instability and degenerative disc desease (DDD). The radicular pain has as most frequent causes a disc herniation and a canal stenosis. Both discogenic and radicular pain also have either a mechanical and an inflammatory genesis. For to be richly innervated, facet joints can be a direct source of pain, while for their degenerative changes cause compression of nerve roots in lateral recesses and in the neural foramina. Degenerative instability is a common and often misdiagnosed cause of axial and radicular pain, being also a frequent indication for surgery. Acute pain tends to extinguish along with its cause, but the setting of complex processes of peripheral and central sensitization may influence its evolution in chronic pain, much more difficult to treat. The clinical assessment of pain source can be a challenge because of the complex anatomy and function of the spine; the advanced imaging methods are often not sufficient for a definitive diagnosis because similar findings could be present in either asymptomatic and symptomatic subjects: a clinical correlation is always mandatory and the therapy cannot rely uniquely upon any imaging abnormalities. Purpose of this review is to address the current concepts on the pathophysiology of discogenic, radicular, facet and dysfunctional pain, focusing on the role of the imaging in the diagnostic setting, to potentially address a correct approach also to minimally invasive interventional techniques. Special attention will be done to the discogenic pain, actually considered as the most frequent cause of chronic low back pain.

Fat saturation technique and gadolinium in MRI of lumbar spinal degenerative disease

We evaluated the potential of MR sequences with Fat Saturation and gadolinium in patients with degenerative disease of the lumbar spine and low back pain, by studying both anterior and posterior elements of the lumbar spine. We examined 3323 patients (age range 15-78 years) presenting low back pain. We used T2-weighted sequences with Fat Saturation and in some selected cases (1063 patients, 32%) administered gadolinium using T1-weighted sequences with Fat Saturation. In particular we used gadolinium in the following cases: 1) presence of hyperintense areas on T2 weighted images with Fat Saturation in the osteo-articular and muscular-ligamentous structures of the lumbar spine; 2) Clinical-radiological discrepancy in patients without disc-root conflict and clinical suspicion of posterior vertebral compartment syndrome. We found degenerative-inflammatory changes in osteo-articular, ligamentous and muscular structures in 1063 patients: osteochondrosis, "aseptic discitis", facet joint effusion and synovitis, osteoarthritis, synovial cysts, spondylolysis, degenerative-inflammatory changes of the posterior ligaments (flava, interspinous and supraspinous ligaments) and posterior perispinal muscles. To improve diagnostic accuracy and allow correct therapeutic guidance, MR examination in patients with low back pain must evaluate both anterior and posterior elements of the lumbar spine. Our study indicates that T2 sequences with Fat Saturation and, in selected cases, gadolinium administration, better visualize or disclose degenerative-inflammatory changes in the lumbar spine, showing the active-inflammatory phase and extension of these processes which may not be depicted during a standard MR examination.

The value of fat saturation sequences and contrast medium administration in MRI of degenerative disease of the posterior/perispinal elements of the lumbosacral spine

Degenerative-inflammatory lumbar spinal pathology is one of the most common reasons why individuals seek medical care, and low back pain is the main symptom among those most commonly associated with this pathologic condition. Pain is commonly attributed to degenerative disc disease, particularly herniated discs, but many different spinal and perispinal structures may undergo degenerative-inflammatory phenomena and produce pain: discs, bone, facet joints, ligaments and muscles. In particular, in patients with non-radicular low back pain, this syndrome may arise from changes of the posterior elements/perispinal tissues of the lumbar spine (i.e., the "posterior vertebral compartment"). They include: facet joint pathology (e.g., osteoarthritis, joint effusion, synovitis and synovial cysts), spondylolysis, spinal/perispinal ligamentous degenerative-inflammatory changes and perispinal muscular changes. It is well known that magnetic resonance is the most sensitive imaging method for the evaluation of spinal degenerative pathology, even in the initial stages of the disease. T2-weighted sequences with fat saturation, and when indicated the use of contrast-enhanced T1-weighted images with fat saturation, permit the visualization of degenerative-inflammatory changes of the posterior elements of the lumbar spine that in most cases would have been overlooked with conventional non-fat suppressed imaging.

Wernicke's encephalopathy induced by total parenteral nutrition in patient with acute leukaemia: unusual involvement of caudate nuclei and cerebral cortex on MRI

We report a 13-year-old girl with leukaemia and Wernicke's encephalopathy induced by total parenteral nutrition. MRI showed unusual bilateral lesions of the caudate nuclei and cerebral cortex, as well as typical lesions surrounding the third ventricle and aqueduct. After intravenous thiamine, the patient improved, and the abnormalities on MRI disappeared.

Enhanced MR in the acute phase of Wernicke encephalopathy

MR in a patient with Wernicke encephalopathy showed enhancement in the mamillary bodies and inferior quadrigeminal plate. These findings pointed to the correct diagnosis, which can be difficult to make in patients who are not alcoholics.

Cerebral ischemia: magnetic resonance angiography and transcranial Doppler evaluation

We examined 21 patients with ischemic cerebrovascular disease using magnetic resonance angiography and transcranial Doppler. In 17 patients (81%), the results obtained by the two methods were concordant. In our opinion, the associated use of transcranial Doppler and magnetic resonance angiography provides an accurate diagnostic evaluation of ischemic stroke patients, not only allowing the site of possible steno-occlusive disease of large and medium cerebral vessels to be identified, but also offering the possibility of obtaining dynamic information concerning the direction of blood flow in the presence of compensatory circulations at the level of Willis' circle.

Thrombotic thrombocytopenic purpura: MR demonstration of reversible brain abnormalities

We report a case of thrombotic thrombocytopenic purpura evaluated by MR. Multiple hyperintense foci on the T2-weighted images, observed principally in the brain stem and in the region of the basal nuclei, and neurologic signs disappeared after 15 days of therapy.

Magnetic resonance angiography monitoring of streptokinase in occlusion of the middle cerebral artery

A 77 year old woman was hospitalized one hour after the onset of right hemiplegia and aphasia. Magnetic resonance imaging (MRI) examination was negative and MRA indicated occlusion of the left middle cerebral artery. Treatment with streptokinase was instituted (a 60 minute intravenous infusion of 1.5 MU of streptokinase in 100 ml of saline solution). Two hours after infusion, the patient's motor function clearly improved. An MRA examination performed six hours later showed partial recanalization of the obstructed vessel. Our report demonstrates the potential usefulness of MRA monitoring during thrombolytic therapy.

MRI and CT evaluation of brain in neurofibromatosis. Case report

Few MRI studies have been performed on subjects with Von Recklinghausen's neurofibromatosis. This not very well-known disease present lesions which in many cases do not appear on CT scans but may be detected by MRI. The nature of such lesions is still controversial. This paper will describe the case of a 7 year-old girl with neurofibromatosis. MRI examination revealed altered signals in some areas: in the basal nuclei, in the brainstem and in the white matter of the cerebellar hemispheres.

Multiple meningiomas diagnosed by computed tomography

This paper reports 11 cases of multiple meningioma diagnosed by CT in the three-year period 1980 to 1983. The pathogenetic problems raised by one case in which von Recklinghausen disease was associated are discussed.

Congenital dislocation of dens of the axis in a case of neurofibromatosis

The clinical and radiological findings in a case of neurofibromatosis with congenital dislocation of dens of the axis are presented.

Clinical and CT parameters in degenerative cerebellar atrophy in aged patients

Fifteen cases of degenerative cerebellar atrophy are presented together with the criteria used to assess the diagnosis of cerebellar atrophy by computed tomography.

Brain-stem hemangioma calcificans. Case report

A case of brain-stem hemangioma calcificans is described. The few cases reported in the literature prove the rarity of this tumor, which is considered a benign variant of cerebral cavernous hemangioma. Diagnosis and treatment of these tumors are briefly discussed with a review of the literature including 11 previous cases.

[Fenestration of the extracranial tract of the vertebral artery: angiographic demonstration of 3 cases]

The authors describe 3 cases of the extracranial Vertebral artery fenestration. This anomaly is a rare case seen in autopsy and angiographically, and in literature too the cases described are few and prevalently by Japanese authors. This anomaly is important because frequently is associated with others congenital intra and extracranial vascular abnormalities.