Intraoperative sonography for spinal tumors. Correlations with MR findings and surgery.

BACKGROUND: To investigate the role of intraoperative ultrasonography during surgery for spinal tumors and the correlation between echographic, magnetic resonance and surgical findings. METHODS: Twenty patients with spinal tumor, explored by MRI of the spine, have been treated with ultrasound-guided surgery. The ultrasound exploration has been performed during laminectomy on the dural surface in all cases and, after the dural opening, on the spinal cord surface for intramedullary tumors. RESULTS: In all patients the ultrasound exploration has allowed to exactly define the extent of the laminectomy, the dural opening and the myelotomy. Meningiomas were hyperechoic and homogeneous, with well defined margins and often visible hyperechoic dural attachment; neurinomas were less hyperechoic and less homogeneous than meningiomas. Intramedullary tumors showed hyperechoic solid and hypoechoic cystic-necrotic components, although a specific tissue characterization (tumor infiltration, gliosis, edema) is not possible. CONCLUSIONS: Intraoperative ultrasonography should be used routinely during surgery for spinal tumors in order to reduce the extent of the laminectomy, dural opening and myelotomy. A good correlation exists between signal intensity on T1-weighted images of MR, the echographic aspect of the tumor and the pathological findings at operation.

Spondylodiscitis. Clinical and magnetic resonance diagnosis.

STUDY DESIGN: This study reviews 65 patients with spondylodiscitis, both spontaneous and postoperative and of different etiology, studied by magnetic resonance imaging. OBJECTIVES: To define the magnetic resonance imaging characteristics of infections of the spine in acute and chronic stages and to evaluate the role of magnetic resonance imaging in defining their etiology. BACKGROUND DATA: Early diagnosis of spondylodiscitis is often difficult because of the long latent period. Radiographs of the spine, bone scan, and computed tomography scan provide insufficient data. METHODS: Among 65 patients with spondylodiscitis studied by magnetic resonance imaging, 24 were examined in the acute stage (clinical evolution between 7 days and 20 days), and 41 were examined in the chronic stage (3-6 weeks). The etiologic agent was staphylococcus in eight cases, Brucella in 13, Mycobacterium tuberculosis in 29, Salmonella in four, and unknown in 11. RESULTS: In cases observed in the acute stage, the disc and the vertebral bodies were hypointense in T1 and hyperintense in T2; this relatively constant finding was not correlated with the etiologic agent. In the chronic stage, cases caused by Brucella or of unknown etiology showed long T1 and T2 relaxation times, with precocious contrast enhancement of the disc; in cases of tubercular etiology there was slight shortening of T1, with inhomogeneous enhancement of the involved vertebral bodies and late disc enhancement. CONCLUSIONS: Magnetic resonance imaging is the investigation method of choice in diagnosing spondylodiscitis, especially in very early stages of the disorder, when other investigations still yield negative results. In chronic stages, magnetic resonance imaging also allows tubercular spondylodiscitis to be distinguished from cases of different etiology.

Coiling of the vertebral artery presenting with neuralgic pain.

A rare case of radicular pain in the arm due to compression of the C6 nerve root by coiling of the vertebral artery is reported; the diagnosis was confirmed by computed tomography (CT), magnetic resonance (MR) angiography and echocolordoppler. Although the enlargement of an intervertebral foramen by a tortuous vertebral artery has been described previously, the occurrence of radicular pain is exceptional. Magnetic resonance imaging (MRI), MR angiography and echocolordoppler allow to differentiate foraminal enlargement due to vascular anomalies of the vertebral artery from that more commonly due to tumor compression, mainly from neurinoma. Surgical decompression may be considered in symptomatic cases.

BAEP and E.M.G. changes from whiplash injuries.

The frequent negativity of neuroradiological changes after neck injury despite the constant complaints (neck pain and stiffness, limited neck movements, arm pains) experienced after a motor vehicle crash has led us to verify the diagnostic and prognostic validity of different neurophysiological tests in these patients. To this aim 120 young patients (67 females and 53 males) referred for a whiplash syndrome aged 18-31 years without neuroradiological abnormalities have been submitted to EMG and BAEP studies immediately after the traffic accident and after six months. Constant slowing of median MNCV and SNCV and ulnar SNCV without changes in morphology, amplitude and duration of MAP and SAP have been observed in 92 patients, with persistent abnormalities in 64 cases after six months. Increase in I-III or I-V interpeak interval of BAEP have been observed unilaterally in 45 patients and bilaterally in 32 ones without changes in absolute latencies and V/I amplitude ratio, with persistence of such abnormalities in 31 and 16 patients respectively after six months. Simultaneous abnormalities of all neurophysiological tests have been observed in 31 patients, with unmodified recordings after six months in 24 patients. The above findings could be accounted for subtle cerebral lesions and a possible damage to brain stem structures as claimed by Ettlin et al. (1992). The usefulness of the above proposed neurophysiological tests in assessment of asymptomatic dysfunction of central motor and sensory pathways in whiplash injuries is discussed.

Intraplaque hemorrhage of the carotid arteries: diagnosis by duplex scanning.

Eighty-three patients with intraplaque hemorrhage of the carotid arteries, explored by Duplex scanning, are reported; 36 among them were also studied by digital angiography and 28 were operated on. The echographic aspect suggesting the presence of an intraplaque hemorrhage is that of a hypo-anechogenic stria separating the intimal plaque from the media-adventitia complex. On the contrary, the angiographic findings are aspecific and unrelated to the presence of intramural blood clots. We think that duplex scanning is the investigation of choice in detecting intraplaque hemorrhage of the carotid arteries. The role of other radiological techniques, such as computed tomography of the neck and magnetic resonance, is also discussed.

Correlation between sex hormone receptors and peritumoral edema in intracranial meningiomas.

Fifty patients with intracranial meningiomas, verified histologically, are retrospectively analyzed to correlate the peritumoral brain edema with the positivity of estrogen receptors and progesterone receptors. The extent of edema was quantified on CT scan and/or MR. Monoclonal antibodies were used to test the estrogen receptors and the dextran-coated charcoal method was used to test the progesterone receptors. Significant levels of both receptors were found in 41 (82%) specimens. 80% of the cases with positive receptors had brain edema, in contrast to only 2 among 9 cases with negative receptors. Thus, the presence of brain edema has resulted to be correlated to the positivity of sex hormone receptors, although we did not find significant correlation between the amount of receptors and the amount of edema. The suggested mechanisms responsible for the brain edema surrounding intracranial meningiomas are discussed. We can suggest that progesterone may induce the secretion of some substances from meningioma cells, such as prostaglandins and biogenic amines, which may result in vagogenic edema.

Cerebral hemorrhagic complication in polyarteritis nodosa. Case report and review of the literature.

Polyarteritis nodosa (PN) is frequently cause of both central and peripheral neurological disorders. However, involvement of the central nervous system is rare at the beginning of the disease. In this paper we report a case of a 38-year-old woman hospitalized in our Neurosurgical Service because of left hemiparesis in presence of cutaneous arteritis (PN). At computed tomography (CT) an intracerebral hemorrhage was found. No radiographic evidences of vasculitis of the visible arterial branches, at angiography, were seen. Cerebral arteritis should be suspected as a cause for intracranial hemorrhage in patients without hypertension or other risk factors.

Spontaneous cure of a ruptured intracranial aneurysm.

A rare case of spontaneous cure of an internal carotid artery aneurysm is reported; the progressive resolution of the spasm and the disappearance of the aneurysm have been confirmed by serial angiograms respectively performed two weeks, two months and four months after the hemorrhage. The other 14 reported cases of angiographically documented spontaneous cure of intracranial aneurysms are reviewed and the possible causes of spontaneous aneurysmal thrombosis, such as retarded cerebral circulation, arterial spasm, size of the neck, thrombosis of the feeding artery and antifibrinolytic therapy, are discussed.

Cavernous angioma of the pineal region.

The pineal region is one of the most rare localizations of intracranial cavernous angiomas, with only 8 cases reported up today. The Authors report a case of cavernous angioma of such localization and review the pertinent literature. Magnetic resonance allows the correct diagnosis of cavernous malformations on the basis of their typical aspect, even in the absence of histological verification. We suggest that this imaging technique will allow to identify more frequently pineal cavernomas preoperatively, thus avoiding useless irradiation.

The role of real time B-mode ultrasonography in the follow-up of patients submitted to carotid endarterectomy.

Sixty-eight patients submitted to carotid endarterectomy for carotid stenosis have been studied periodically by B-mode real time ultrasonography. This non-invasive investigation allows to detect not only a recurrent stenosis, but also minor changes following endarterectomy, including suture, lesions from clamps, myointimal proliferation, and intimal flaps. We think that all patients submitted to carotid endarterectomy must be explored periodically by duplex scanning, in order to follow-up the normal and pathological changes of the arterial wall.

Olfactory groove meningioma and multiple aneurysms. Case report.

We report a case of a patient with olfactory groove meningioma associated with multiple aneurysms. The association between intracranial aneurysms and meningiomas is infrequent and perhaps it is due to chance alone; many theories have been formulated to explain it. In the cases with both lesions, meningiomas are more frequently located at level of the convexity while aneurysms are more often located at level of the anterior cerebral-anterior communicating artery complex or at level of the middle cerebral artery.

Diagnosis of carotid artery occlusion by duplex scanning.

This paper reviews 70 patients, with complete occlusion of the internal carotid artery, investigated by duplex scanning. The correlation between the echogenicity of the occlusion (anechogenic, hypoechogenic or hyperechogenic) and the time interval between the ischaemic symptoms and the ultrasonic investigation showed that some occlusions are hypoanechogenic and others hyperechogenic, in spite of the time interval, and consequently the echogenicity of the occlusion cannot be correlated with the time of its formation. Duplex scanning allows a correct diagnosis in almost all cases of carotid artery occlusion by comparison of the morphological and flowmetric data. The 95% sensitivity in 20 cases was explored by digital angiography also. It was concluded that angiography was usually unnecessary to confirm a carotid occlusion and its use could be limited to rare, doubtful, cases and to patients with contralateral stenosis i.e. candidates for surgery.

Megadolichobasilar artery and acute cerebrovascular pathology.

Sixteen patients with a megadolichobasilar artery and acute cerebrovascular symptoms are reported. All were explored by computerized tomography and vertebral angiography. Nine had transient ischaemic attacks or definitive ischaemic lesions, whereas 7 had subarachnoid or intracerebral haemorrhage. Among the patients with ischaemic troubles, vertebro-basilar insufficiency and pontine infarction were the most common clinico-radiological findings. Among the patients with intracranial haemorrhage, 4 had associated aneurysms or arteriovenous malformations, while 3 had subarachnoid or intracerebral haemorrhage with no vascular malformations on the angiograms. The possible relationships between the megadolichobasilar anomaly and the cerebral ischaemic or haemorrhagic pathologies are discussed also from a review of the pertinent literature.

Transient visual symptoms and carotid artery disease. Exploration by real-time B-mode echotomography.

The real-time B-mode echotomographies of 100 patients with transient visual symptoms have been reviewed and their findings have been compared with those of other 100 patients with transient ischemic attacks, who never had visual disturbances in their clinical history. The rate of pathologic echotomographies was higher in the group of patients with transient visual symptoms (72%), who also had a higher percentage (50% of the positive cases) of small or mild plaques without significant hemodynamic effects. The amaurosis fugax, particularly when associated with hemispheric ischemic symptoms, should suggest a carotid disease. The non-invasive exploration by real-time B-mode echotomography and Doppler with spectral analysis is the method of choice for the diagnosis of patients with transient visual symptoms.

Oestrogen and progesterone sensitivity in cultured meningioma cells.

Several studies have detected oestrogen and progesterone receptors in meningioma specimens; recently we have also confirmed the presence of steroid receptors in cultured cells from meningiomas. This paper describes the oestrogen and progesterone receptor assay in cultured cells from 6 meningiomas and the influence of steroid hormones on the cell growth and morphology. Four (66%) of the 6 specimens were positive for both receptors. Growth of cultured cells from tumours without receptors is not appreciably modified by the addition of hormones; the cultured cells from tumours with positive receptors are not essentially influenced by oestrogen, whereas progesterone produces a rapid and marked suppression of the cell growth and modifies their form and adhesivity; also the addition of an oestrogen and progesterone blend produces growth suppression. A similar effect of the progesterone on the cultured cells has also been obtained in a specimen of malignant meningioma. The results of this study suggest that the modulation of progesterone levels may be of therapeutic usefulness, particularly in patients with recurrent malignant meningiomas.

Fibromuscular dysplasia of the carotid arteries. Clinical and radiological considerations.

Seven patients with fibromuscular dysplasia of the carotid arteries are described. Three were asymptomatic and four had ischemic troubles. Angiographically, 3 had a fibromuscular dysplasia of type 1 and 4 of type 2; one patient also had an associated aneurysm of the cervical internal carotid artery. The neurological troubles and their pathogenesis, the angiographic findings and the differential diagnosis of this angiopathy are briefly discussed; the surgical procedures and their risks are also analyzed.

Nonobstructive symptomatic plaques of the carotid bifurcation: echotomographic-angiographic correlations.

This study reports a selected group of 45 patients with symptomatic low-grade stenoses of the carotid bifurcations, detected by real-time B-mode echotomography, and correlates the results of this technique with those of the Doppler flow study and carotid angiography. The Doppler study with spectral analysis was negative in all cases, whereas a correlation between the echotomographic and angiographic results was observed in 20 among 27 patients explored by angiography (74%). The causes of failure of angiography in some cases are briefly discussed. The almost absolute sensitivity of high resolution B-mode echotomography in detecting these early, sometimes symptomatic atherosclerotic changes of the carotid artery wall is emphasized.

[Clinical evaluation of aztreonam in the prevention and therapy of infections in patients subjected to neurosurgical intervention]. / Valutazione clinica dell'aztreonam nella profilassi e terapia delle infezioni in pazienti sottoposti ad intervento neurochirurgico.

Twenty-six neurosurgery patients were given prophylactic treatment with Aztreonam at a dose of 1 g every 8 hours (30 mg/kg every 12 hours in children) for 8-12 days after the operation. In 18 cases 300 mg Clindamycin was also given every 8 hours for 8 days. No local or general infections arose in the postoperative period. Three patients with infections caused by susceptible bacteria were given 1 g Aztreonam every 6 hours (30 mg/kg every 8 hours in children) for 8 days. In all cases all clinical and microbiological signs of the infection had disappeared by the end of treatment. Apart from one episode of mild nausea no side effects were noted. Aztreonam is therefore considered a safe and effective drug for the treatment and prophylaxis of postoperative infections in neurosurgery.

The blood leukocyte count and its prognostic significance in subarachnoid hemorrhage.

This study reviews the white blood cell count in 75 patients with subarachnoid hemorrhage and correlates it with the clinical grade at admission, the outcome, the presence of angiographic spasm and blood clots in the cisternal spaces. Patients with subarachnoid hemorrhage with normal angiograms usually have slow white cell count and favourable outcome. In patients with subarachnoid hemorrhage due to ruptured aneurysms, their'is a clear correlation between the cell count and the entity of the cisternal hemorrhage and arterial spasm. Whereas the cell count is fairly correlated with the clinical grade at admission, a cell count exceeding 20,000 in associated with a 90% rate of poor outcome, even in patients with low clinical grade at admission. Therefore the count of the white blood cells seems to have high prognostic value in predicting the neurological deterioration due to arterial spasm.