Neural correlates of worry in generalized anxiety disorder and in normal controls: a functional MRI study.

BACKGROUND: Worry is considered a key feature of generalized anxiety disorder (GAD), whose neural correlates are poorly understood. It is not known whether the brain regions involved in pathological worry are similar to those involved in worry-like mental activity in normal subjects or whether brain areas associated with worry are the same for different triggers such as verbal stimuli or faces. This study was designed to clarify these issues. METHOD: Eight subjects with GAD and 12 normal controls underwent functional magnetic resonance imaging (fMRI) mood induction paradigms based on spoken sentences or faces. Sentences were either neutral or designed to induce worry. Faces conveyed a sad or a neutral mood and subjects were instructed to empathize with those moods. RESULTS: We found that the anterior cingulate and dorsal medial prefrontal cortex [Brodmann area (BA) 32/23 and BA 10/11] were associated with worry triggered by sentences in both subjects with GAD and normal controls. However, GAD subjects showed a persistent activation of these areas even during resting state scans that followed the worrying phase, activation that correlated with scores on the Penn State Worry Questionnaire (PSWQ). This region was activated during the empathy experiment for sad faces. CONCLUSIONS: The results show that worry in normal subjects and in subjects with GAD is based on activation of the medial prefrontal and anterior cingulate regions, known to be involved in mentalization and introspective thinking. A dysregulation of the activity of this region and its circuitry may underpin the inability of GAD patients to stop worrying.

With time on our side? Task-dependent compensatory processes in graceful aging.

Graceful aging has been associated with frontal hyperactivations in working- and episodic long-term memory tasks, a compensatory process, according to some, that allows the best normal elders to perform these tasks at a juvenile level, in spite of natural cortical impoverishment. In this study, 24 young and 24 healthy elderly participants were compared. Graceful aging was explored by investigating domains where most healthy elders perform like youngers (e.g. lexical-semantic knowledge) and tasks that are typically more challenging, like episodic long-term recognition memory tasks. With voxel-based morphometry, we also studied to what extent changes of fMRI activation were consistent with the pattern of brain atrophy. We found that hyperactivations and hypoactivations of the elders were not restricted to the frontal lobes, rather they presented with task-dependent patterns. Only hypoactivations and normal levels of activation systematically overlapped with regional atrophy. We conclude that compensatory processes associated with graceful aging may not necessarily be a sign of early saturation of executive resources, if this was to be represented by a systematic frontal hyperactivation, but rather they may represent the ability of recruiting new cognitive strategies. We discuss two possible approaches to further test this hypothesis.

Anatomy of the episodic buffer: a voxel-based morphometry study in patients with dementia.

In 2000 Baddeley proposed the existence of a new component of working memory, the episodic buffer, which should contribute to the on-line maintenance of integrated memory traces. The author assumed that this component should be critical for immediate recall of a short story that exceeds the capacity of the phonological store. Accordingly, patients with Alzheimer's dementia (AD) should suffer of a deficit of the episodic buffer when immediate recall of a short story is impossible. On the other hand, the episodic buffer should be somewhat preserved in such patients when some IR can occur (Baddeley and Wilson, 2002). We adopted this logic for a voxel-based morphometry study. We compared the distribution of grey-matter density of two such groups of AD patients with and of a group of age-matched controls. We found that both AD groups had a significant atrophy of the left mid-hippocampus; on the other hand, the anterior part of the hippocampus was significantly more atrophic in patients who were also impaired on the immediate prose recall task. Six out of ten patients with no immediate recall were spared at "central executive" tasks. Taken together our findings suggest that the left anterior hippocampus contributes to the episodic buffer of the revised working memory model. We also suggest that the episodic buffer is somewhat independent from the central executive component of working memory.

Angiographic follow-up of traumatic carotid cavernous fistulas treated with endovascular stent graft placement.

BACKGROUND AND PURPOSE: Endovascular treatment (EVT) of carotid cavernous fistulas (CCFs) is based on various techniques, mainly those using detachable balloons. Coronary covered stent grafts have been sporadically used in the intracranial arteries and only 2 traumatic CCFs have been reported in the literature; moreover, there is poor information about the long-term follow-up. We present 8 cases of CCFs treated by the placement of a covered stent, 5 of which have a 1-year clinical and angiographic follow-up. METHODS: Eight patients with posttraumatic CCF were treated by positioning a covered stent in the intracranial internal carotid artery (ICA) to occlude the fistula. They received periodic clinical and angiographic follow-up to evaluate the patency and the stability of clinical results. RESULTS: In all cases, the symptoms related to the CCF regressed after treatment and did not recur in the follow-up. Two patients presented residual filling of the CCF at the end of the procedure. The angiographic follow-up revealed in 6 patients of 7 a good patency of the ICA; in 1 patient, there was an ICA asymptomatic occlusion. One patient required transvenous coil occlusion of the cavernous sinus. CONCLUSION: When standard treatments fail, covered stent grafts can be used as a valid alternative in the treatment of CCFs, but more data are needed, especially in the long-term follow-up.

Reversible ischemic attacks with normal angiogram: risk factors, clinical findings, and prognosis.

One hundred seventeen patients with reversible ischemic attacks were divided into two groups according to the presence of atheromatous lesions on angiography. Female sex, vertebrobasilar territory involvement, and younger age were related to normal angiograms. Among risk factors, only hypertension was associated with atheroma. However, the number of risk factors in each patient was related linearly to angiographic abnormality. Later stroke and myocardial infarction were significantly more common in patients with atheromatous lesions.

Treatment of vascular lesions with balloon catheters.

During a 4 year period, 48 patients were treated with balloon catheters. There were 39 fistulas and nine aneurysms. Detachable balloons with a modified Debrun technique were used in 37 patients. Different kinds of technical problems were encountered. The arterial axis remained patent in 29 of the 37 fistulas; in the two mixed internal and external carotid-cavernous sinus fistulas, combined embolization with dura, isobutyl cyanoacrylate, and detachable balloon was used. In six of the nine aneurysms the arterial axis was occluded with a detachable balloon. In three of 48 patients, severe neurologic complications resulted in death.

MR of corticotropin-secreting pituitary microadenomas.

PURPOSE: To assess the accuracy of MR in the preoperative identification of corticotropin-secreting pituitary microadenomas. METHODS: Twenty-six patients with clinical and biochemical evidence of pituitary-driven Cushing disease in whom MR of the seller region was performed were selected for this study. The MR examinations were retrospectively evaluated by a neuroradiologist who was aware of the presence of an adenoma at surgery but not of location and size of the lesion. RESULTS: Considering the whole group of MR examinations performed either without (n = 26) or without and with intravenous injection of gadopentetate dimeglumine (n = 16), overall 20 MR studies were judged to show disease. Seventeen of 26 microadenomas were adequately shown and located by MR (true-positive, 65.4%). In three cases the sides of the microadenomas were misjudged (false-positive, 11.5%). Six patients had negative MR studies (false-negative, 23%). Twelve of the 16 patients studied after gadopentetate dimeglumine injection had true-positive MR findings (75%). CONCLUSIONS: In our experience the accuracy of MR in detecting corticotropin-secreting microadenomas as small as 2 to 3 mm is 65% to 75%. Although precontrast images provide diagnostic information, the microadenoma can be better seen with administration of contrast material.

Giant extramedullary arteriovenous fistula supplied by the anterior spinal artery: treatment by detachable balloons.

A case of a large extramedullary arteriovenous fistula in a young man, which was deemed inoperable, is described. The fistula was mainly supplied by the anterior spinal artery and was responsible for a progressive myeloradicular syndrome. Successful treatment with detachable balloons was carried out. Along with this case report, a review is made of the different types of extramedullary arteriovenous fistulas and their treatment based upon 11 cases seen at Lariboisière Hospital: type 1 is a plain small fistula where embolization is contraindicated; type 2 shows an enlarged anterior spinal artery with dysplastic vein and may be embolized with solid particles; type 3 is a very large multipediculated fistula where the best treatment seems to be detachable balloons. The indications for using detachable balloons for temporary occlusion and for definitive treatment are reviewed. Special emphasis is placed on the possibility of detaching balloons without the need for a coaxial catheter.

Myelopathy and radiculopathy due to cervical spondylosis: myelographic-CT correlations.

Forty patients with symptoms and signs of radicular disease or spinal cord involvement secondary to cervical spondylosis were studied with myelography (using nonionic water-soluble contrast medium) followed by computed tomographic (CT) myelography. In 17 patients CT was also performed before myelography. CT myelography adds useful information to the myelographic findings. Cord compression is better evaluated and osteophytes can be differentiated from disk herniation. Plain CT can demonstrate a herniated disk but with less accuracy than CT myelography. Cord and root compression are not seen directly on plain CT; for this reason myelography should be the first procedure in patients with myelopathy or myeloradiculopathy, which may be followed by CT myelography.

Repeated subarachnoid hemorrhages from a cervical meningioma. Case report.

Magnetic resonance imaging (MRI) of the head and cervical spine unexpectedly revealed a cervical meningioma in a patient who had suffered repeated episodes of subarachnoid hemorrhage. The importance of MRI in the diagnosis of tumors in patients with unusual clinical presentation is stressed.

Surgical interruption of leptomeningeal drainage as treatment for intracranial dural arteriovenous fistulas without dural sinus drainage.

Intracranial dural arteriovenous fistulas (AVFs) have been recognized as acquired lesions that can behave aggressively depending on the pattern of venous drainage. Based on the type of venous drainage, they can be classified as fistulas drained only by venous sinuses, those drained by venous sinuses with retrograde flow in arterialized leptomeningeal veins, and fistulas drained solely by arterialized leptomeningeal veins. Serious symptoms, including hemorrhage and focal deficit, are related to the presence of arterialized leptomeningeal veins. In this paper, the authors report a consecutive series treated between 1988 and 1993 of 20 cases of intracranial dural AVFs with "pure leptomeningeal drainage." All patients underwent surgical interruption of the leptomeningeal draining veins. Based on the arterial supply, nine patients were managed by direct surgery, whereas 11 patients were prepared for surgery by means of preoperative arterial embolization. Radioanatomical cure of the fistula and good neurological recovery were achieved in 18 cases. Complete obliteration of the fistula was documented angiographically in two cases, but fatal hemorrhage occurred, probably due to partial thrombosis of the venous drainage. Based on this experience, the authors believe that surgical interruption of the draining veins is the best treatment option for intracranial dural AVFs. However, surgical results may be affected by the extension of postoperative thrombosis, which in turn may be related to the degree of preoperative venous engorgement.

Endovascular treatment with GDCs: results in 100 patients.

BACKGROUND: In this paper we review the clinical and morphological results of intracranial aneurysms treated with Guglielmi Detachable Coils. METHODS: We report our experience in 100 patients with intracranial aneurysms treated with GDC. Since February 1993 we have treated 70 females and 30 males, with a mean age of 57 years old, for a total of 118 intracranial aneurysms. Sixty-five patients had a recent history of ruptured aneurysm, 10 suffered from a previous subarachnoid hemorrhage and 25 patients had never bled. In the choice of treatment for subarachnoid aneurysm, in accordance with our neurosurgeons, we have not applied a protocol, rather we have followed guidelines in relation to: age, neurological clinical conditions, systemic disease and location of aneurysm. Morphological aspect of immediate aneurysm occlusion was: 60% more or less complete occlusion, 30% loose packing with 10% failures. RESULTS AND CONCLUSIONS: The clinical outcome at follow-up (1 month-3 years) was: 72 patients without neurological deficits, 19 patients improved pre-existing neurological deficits, 3 patients worsened for procedural complications; 6 patients died (1 patient unrelated).

Hydatid disease of spine. A case report.

Hydatid disease of the primary type may involve CNS and bone. Compression of the spinal cord and spinal nerve roots, caused by hydatid material from an affected vertebra is a rare condition which makes surgical decompression mandatory. We report the neuroradiological findings in a case of vertebral hydatidosis, confirmed by surgical appearance and hystological examination.

Embolization of vascular malformations of the spinal cord.

Twelve patients with vascular malformations of the spinal cord have been treated by embolization at the Neuroradiological Department of the Ospedale Maggiore Niguarda Cà Granda from September 1981 to February 1984. Different materials and techniques have been used, including liophylised dura, Ivalon (PVA) and Isobutyl Cianoacrylate. All types of malformations have been encountered: dural AV fistulae, intramedullary AVMs, intradural extramedullary AV fistulae, extradural AVMs with intradural venous drainage. Nine patients improved following treatment and three remained unchanged. Embolization can be an alternative treatment to surgery and it is the treatment of choice in dural AV fistulae.

Multidisciplinary (surgical and endovascular) approach to intracranial aneurysms.

In spite of the availability of the new endovascular technique (GDC) to manage cerebral aneurysms, to date, the crucial question "which is the proper treatment in a given patient?" still remains unsettled. In order to check whether an answer is possible, we retrospectively reviewed a personal series of 192 consecutive patients with cerebral aneurysms (1993-1995). We found 164 patients who had been considered eligible for active aneurysm treatment. Treatment modality has been chosen case by case on the basis of patient conditions, and aneurysm size and location. Four groups of patients were identified: Group 1: 104 patients (63.4%) with subarachnoid hemorrhage (SAH) in whom the treatment of choice was surgery; Group 2: 27 SAH patients (16.4%) in whom the first choice was GDC; Group 3: 7 SAH patients (4.2%) who died before the scheduled treatment; Group 4: 26 patients (15%) with not ruptured aneurysm who had either surgery or GDC. Based on the results of this series (improvement of the overall results through the multidisciplinary approach), we have developed the guidelines to prospectively manage future cases of cerebral aneurysms with the purpose to rationalize the management, thus further improving the overall results.

Neuroimaging of focal cortical dysplasia: neuropathological correlations.

Focal cortical dysplasia is a well-known cause of intractable epilepsy with early onset of seizures, and is potentially amenable to surgical therapy. It was first described by Taylor in 1971 as a peculiar malformative disorganisation of the neocortex characterised at histology by loss of cortical lamination and accompanied by giant, dysmorphic neurones and, most frequently, by "balloon cells" littered throughout the cortex and sub-cortical white matter. While in the past decades the term "cortical dysplasia" has referred to various malformations of cortical development, such as agyria, pachygyria, polymicrogyria, heterotopia and hemimegalencephaly, it is now widely accepted that the entity identified by Taylor should be considered separately, from both histological and neuroimaging standpoints. More recently, the recognition of various histological subtypes of focal cortical dysplasia characterised by different degrees of cortical disruption with or without cytological abnormalities has generated several classifications that are still unsatisfactory. With better magnetic resonance capability, subtle and very small focal cortical dysplasias may now be visualised and the differential magnetic resonance aspects of the histological subgroups can be established. We will discuss the problem of histopathological classification and magnetic resonance imaging differentiation of the various subtypes of focal cortical dysplasia in the light of personal data collected from a large series of epileptic patients who underwent surgery and had a histological diagnosis of focal cortical dysplasia.

Intracerebral venous hemorrhage in "high-risk" carotid-cavernous fistula.

Intracerebral hematoma associated with carotid-cavernous fistula is a rare occurrence. Based on a review of the literature and on the analysis of personal observation, the authors define as "high-risk fistula" a carotid-cavernous fistula at risk of intracerebral hemorrhage. Characteristic features of these are computed tomography demonstration of parenchymal vermicular enhancement of brain vessels, and an angiographic pattern of dilated and tortuous cerebral veins. When an intracerebral hemorrhage occurs in a patient with carotid-cavernous fistula an early but phased and combined neuroradiological-neurosurgical approach is suggested as the best way to treat this life-threatening situation.

Morphological and blood flow MR findings in cerebral vascular malformations.

The authors report MR findings in 139 patients with 159 cerebral vascular malformations (36 arteriovenous malformations, 25 venous angiomas and 98 cavernous angiomas). Morphological aspects and hemodynamic findings due to rapid and slow flow are analysed. MR is able to differentiate the various type of lesions and permits the visualization of angiographically occult vascular malformations. In the case of cavernous angiomas MR information may not be sufficient for an absolute diagnosis because of differential diagnostic problems; correlation with the clinical history, CT and angiographic findings and follow-up MR study are certain to be necessary to increase specificity. Usually it is possible to distinguish histopathological components of the lesion and perilesional modifications in the cerebral parenchyma.