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L Remonda

Publications and source records attributed to L Remonda.

At least 19 recordsLinked to original sources
PubMed2002

Magnetic resonance angiography with ultrashort echo times reduces the artefact of aneurysm clips.

We evaluated the ability of an ultrashort echo time (TE) three-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography (MRA) sequence to reduce the metal artefact of intracranial aneurysm clips and to display adjacent cerebral arteries. In five patients (aged 8-72 years) treated with Elgiloy or Phynox aneurysm clips we prospectively performed a conventional (TE 6.0 ms) and a new ultrashort TE (TE 2.4 ms) 3D TOF MRA. We compared the diameter of the clip-induced susceptibility artefact and the detectability of flow in adjacent vessels. The mean artefact diameter was 22.3+/-6.4 mm (range 14-38 mm) with the ultrashort TE and 27.7+/-6.4 mm (range 19-45 mm) with the conventional MRA ( P<0.0001). This corresponded to a diameter reduction of 19.5+/-9.2%. More parts of adjacent vessels were detected, but with less intense flow signal. The aneurysm dome and neck remained within the area of signal loss and were therefore not displayed. Ultrashort TE MRA is a noninvasive and fast method for improving detection of vessels adjacent to clipped intracranial aneurysms, by reducing clip-induced susceptibility artefact. The method cannot, however, be used to show remnants of the aneurysm neck or sac as a result of imperfect clipping.

Adult↗
PubMed2002

Whole-brain functional magnetic resonance imaging of cerebral arteriovenous malformations involving the motor pathways.

To investigate cortical, basal ganglia and cerebellar activation in patients with arteriovenous malformations (AVMs) involving the motor pathways, we studied ten patients (six male, four female, mean age 30.3 years, range 7.4-44.1) by whole-brain functional magnetic resonance imaging (fMRI) in a 1.5-T scanner with the EPI-BOLD-technique. In seven cases multiple fMRI studies were available, acquired in the course of the multi-session endovascular interventional treatment. Self-paced right- and left-handed finger-tapping tasks were used to invoke activation. In six patients a super-selective amytal test (Wada test) was performed during diagnostic pre-interventional angiography studies. Abnormal cortical activation patterns, with activation of the primary sensorimotor area, the supplementary motor area and/or the cerebellum shifted to unphysiological locations, were found in four patients. In all cases, localization of the AVM could account for the changes from the normal. After endovascular procedures, fMRI demonstrated shifts in the activation pattern in three patients. In the six patients that had undergone fMRI studies and the Wada test, both methods yielded comparable results. The fact that AVMs are structural anomalies for which the brain can partly compensate ('plasticity') was underlined by these results. fMRI is a valuable tool in the pre-therapeutic evaluation and post-interventional follow-up of patients with cerebral AVMs in whom an operation or an endovascular procedure is planned.

Adolescent↗
PubMed2002

Presumptive monosomy 21 with neuronal migration disorder re-diagnosed as de novo unbalanced translocation t(18p;21q) by fluorescence in situ hybridisation.

We present clinical and cytogenetic data of a one year old boy with partial monosomy for both 21q and 18p, resulting from a de novo unbalanced translocation. The initial diagnosis of a seemingly full monosomy 21 was revised after fluorescence in situ hybridisation (FISH) with whole chromosome painting probes and a locus-specific chromosome 21 probe. The karyotype was reinterpreted as 45,XY,der(18)t(18;21)(p11.2;q22.1),-21. This karyotype, to our knowledge, has not been previously described. The boy presented with a spectrum of clinical features previously described for (partial) monosomy 18p only, for monosomy 21q only, or for both of these aneusomies. The radiological finding of a neuronal migration disorder with localised polymicrogyria (cortical dysplasia) has not been described for either monosomy before.

Abnormalities, Multiple↗
PubMed2001

Reperfusion demonstrated by apparent diffusion coefficient mapping after local intra-arterial thrombolysis for ischaemic stroke.

Diffusion-weighted MRI (DWI) is becoming important for diagnosis and investigation of acute cerebral ischaemia. It has been reported that apparent diffusion coefficient (ADC) maps could be an indicator of reperfusion. Our aim was to use echo-planar technology to investigate this phenomenon. We report 19 patients treated by local intra-arterial thrombolysis for middle cerebral artery stroke within 6 h of the onset of symptoms, in whom we performed follow-up DWI. ADC were found to be higher in the patients with angiographically proven reperfusion.

Adult↗
PubMed2001

Intermittent visual loss and exophthalmos due to the Blue rubber bleb nevus syndrome.

PURPOSE: To describe the occurrence of intermittent visual loss in a patient with orbital hemangioma due to the blue rubber bleb nevus syndrome. METHODS: Case report. RESULTS: A 70-year-old woman complained of intermittent blurred vision combined with pressure behind her left eye occurring after head bending or Valsalva maneuvers. Examination revealed 2 mm of enophthalmos on the left. After downward bending of the head the eye became exophthalmic by 12 mm and visual acuity decreased to finger counting. Neuro-ophthalmologic examination was otherwise normal. Magnetic resonance imaging revealed an intraconal hemangioma. Bluish, soft, rubber-like, compressible and slowly refilling hemangiomas on the inferior lip, sublingually, on the hand, and vagina led to the diagnosis of BRBNS. CONCLUSIONS: Intermittent visual loss may be the presenting symptom of an orbital hemangioma in BRBNS. Recognition of this rare condition is important because of its potentially life-threatening complications.

Aged↗
PubMed2001

Diffusion-weighted mr in cerebral venous thrombosis.

The diagnosis of cerebral venous thrombosis is often difficult both clinically and radiologically and until now there is no method available to predict if brain lesions, detected clinically and using conventional brain imaging methods, may lead to full recovery, as expected in vasogenic edema or ischemic infarcts and even a hematoma. New fast neuroimaging techniques such as diffusion-weighted imaging (DWI) are sensitive to different reasons of changes in local tissular water concentration thus giving further insight into the pathophysiological mechanism as well as prognosis of cerebral venous thrombosis. We report the cases of 18 consecutive patients with a diagnosis of cerebral venous thrombosis based on clinical and imaging criteria. All patients underwent magnetic resonance imaging (MRI) of the brain, which comprised isotropic diffusion-weighted MR. Diffusion-weighted MRI showed positive findings in 17/18 cases. In 7 cases the clot could be directly visualized as an area of hyperintensity in the affected vein on DWI. In 7 cases DWI showed areas of signal loss corresponding to hematomas. In 6 cases DWI showed changes in signal intensity that were more subtle. In 4 cases of superficial venous thrombosis, there were areas of decreased ADC values (0.65-0.79 x 10(-3) mm(2)/s) whereas in 2 cases of deep venous thrombosis, increased DWI intensities could be found that corresponded to both an increase and a decrease in ADC, corresponding to a coexistence of cytotoxic and vasogenic edemas. Diffusion-weighted MRI can demonstrate directly the presence of an intravenous clot in a select number of patients. It can also demonstrate early ischemic changes, and can differentiate conventional T2-weighted MR areas of cytotoxic from vasogenic edema.

Adult↗
PubMed2000

[Results and role of carotid endarterectomy].

BACKGROUND: The indications for carotid endarterectomy have been defined on the basis of several large prospective randomised trials. Today this operation is widely performed as primary and secondary stroke prevention in patients with high grade carotid artery stenosis. Permanent quality control of the surgical results is mandatory to ensure optimal stroke prevention and further reduce perioperative complications. METHODS: In this retrospective study we analyse the surgical results of 272 consecutive carotid endarterectomies performed in 260 patients with special emphasis on the prevention of intraoperative brain ischaemia. Patients were operated on in general anaesthesia and moderate hypothermia. Before clamping the arteries at the neck, a fast-acting barbiturate or propofol was administered intravenously to obtain burst suppression on the EEG. Transcranial Doppler sonography allowed continuous intraoperative monitoring of brain perfusion and detection of emboli. Intraoperative shunting was performed only when the collateral circulation was insufficient. RESULTS: The postoperative course was uneventful in 249 endarterectomies (91.5%). The internal carotid artery was sonographically recanalised at hospital discharge and at 6-week follow-up in all 249 cases. Ischaemic cerebral complications were observed in 7 patients (2.6%): minor reversible brain ischaemia in 4 (1.5%), and major brain ischaemia with infarction in 3 (1.1%). Three patients died in the perioperative period, representing a mortality rate of 1.1% in this series. The overall combined stroke and death rate was 3.7%. The combined major stroke and death rate was 2.2%. Various non cerebral complications occurred in 13 patients (4.8%). CONCLUSIONS: These results confirm that endarterectomy is a safe and efficient treatment for atherosclerotic carotid stenosis at the neck. Very low complication rates can be attained by non-invasive diagnostic methods combined with intraoperative monitoring of cerebral blood flow velocity. New upcoming endovascular therapies such as percutaneous angioplasty and stenting need to be compared with these current surgical results with regard not only to perioperative morbidity and mortality but also patency rate, restenosis, and intracerebral blood flow restoration.

Adult↗
PubMed2000

Recovery from spontaneous confabulations parallels recovery of temporal confusion in memory.

BACKGROUND: In previous studies, the authors found that patients with spontaneous confabulation differ from those with nonconfabulating amnesia by 1) temporal context confusion (TCC) in memory based on an inability to suppress intrusions of currently irrelevant memory traces into ongoing thinking; and 2) lesions involving the orbitofrontal cortex, basal forebrain, or amygdala and perirhinal cortex. OBJECTIVES: To study the long-term clinical course of spontaneous confabulations, determine whether TCC in memory also parallels the clinical course of spontaneous confabulations, and study the impact of lesion site on clinical course. METHODS: Eight patients with spontaneous confabulation were re-examined 18 months after onset. Tests of memory and executive functioning and measurement of TCC in memory were again applied. MRI according to a standard protocol was performed to determine areas of permanent damage. RESULTS: Seven patients eventually stopped confabulating. TCC, but not common memory or executive tests, precisely paralleled the course of spontaneous confabulations. Patients with isolated, less extensive, orbitofrontal lesions stopped confabulating first and had the best neuropsychological outcome. Patients with basal forebrain lesions continued to confabulate for several months and remained amnesic. One patient with extensive orbitofrontal damage and perirhinal cortex damage continues to confabulate after more than 3 years, continuing to confuse memory traces. CONCLUSIONS: Temporal context confusion in memory is not only the sole feature reliably separating patients with spontaneous confabulation from those with nonconfabulating amnesia in the acute stage, it is also the only feature that precisely parallels the clinical course of spontaneous confabulations. Most patients eventually stop confabulating but duration of confabulations depends on the lesion site.

Adult↗
PubMed2000

Endovascular treatment of acute and subacute hemorrhage in the head and neck.

OBJECTIVE: Acute and subacute hemorrhage in the head and neck often represent a life-threatening situation. The goal of this study is to evaluate the indications for and contributions of endovascular techniques in the diagnosis and management of such severe cases. DESIGN: Seventy-two patients with acute or subacute intractable hemorrhage of the head and neck were treated over a period of 5 years: 2 patients had experienced trauma; in 6 cases the cause of bleeding was iatrogenic; and in 2 patients intraosseous arteriovenous malformations were manifested. Fifteen patients had tumors, 9 of whom had prior radiotherapy. Forty-seven patients presented with epistaxis (41 idiopathic and 6 during anticoagulation therapy). The endovascular therapy was performed using polyvinyl alcohol particles, fibered platinum or electrolytically detachable coils (Guglielmi detachable coils; Target Therapeutics, Fremont, Calif), a stent, glue (Ethibloc; Ethicon GmbH, Norderstedt, Germany, and Histoacryl; B. Braun Melsungen AG, Melsungen, Germany), or with a combination of these different embolic materials. RESULTS: The acute bleeding was successfully controlled in all cases. Fourteen patients (7 with epistaxis, 5 with tumors, and 2 with arteriovenous malformations) had to be embolized more than once before the bleeding could be controlled. The idiopathic, traumatic, iatrogenic, and remaining tumoral cases were treated only once. The long-term morbidity was 1.9%. CONCLUSIONS: Owing to the recent continuous advances in interventional radiologic techniques, it is possible to treat both acute and subacute life-threatening head and neck hemorrhage most efficiently. In many cases the endovascular therapy complements surgery.

Acute Disease↗
PubMed2000

Diffusion-weighted MRI suggests the coexistence of cytotoxic and vasogenic oedema in a case of deep cerebral venous thrombosis.

We report a 20-year-old woman who suffered headaches before presenting with a state of fluctuating vigilance. MRI showed diffuse high signal in the basal ganglia bilaterally on diffusion- and T2-weighted images, which had areas of both low and high apparent diffusion coefficient, presumed to correspond to cytotoxic and vasogenic oedema. MR venography showed no flow in the deep cerebral veins or straight sinus. Heparin was given, with clinical recovery. On follow-up MRI, the appearances became normal.

Adult↗
PubMed2000

Diffusion-weighted MRI for monitoring neurovascular interventions.

Carotid stenting is increasingly considered as treatment for carotid artery disease. A reliable noninvasive method is desirable for assessing the safety of the procedure. Diffusion-weighted MRI (DWI) is sensitive to early brain ischaemia which becoming widely available and might therefore serve this purpose. We prospectively studied 19 patients referred for investigation of carotid artery disease by echo-planar whole-brain DWI before and within 24 h of stenting. The images obtained at a high b value were examined by two independent blinded reviewers for new high-signal areas consistent with ischaemia. We found that 15 patients had no new changes after stenting. One patient showed enlargement of a posterior watershed lesion after the procedure, which correlated with an increase in neurological deficit. Three other patients had presumed small embolic infarcts on DWI; two were asymptomatic and one had weakness at the hand that corresponded to an embolic infarct with a lesion on DWI in the hand notch. There were no false- positive or -negative results on DWI, when compared to clinical findings. DWI is thus a new method that can demonstrate neurologically silent or asymptomatic infants. It can be used to help to assess the safety and efficacy of neurovascular intervention.

Adult↗
PubMed2000

Diffusion-weighted imaging in ischaemic stroke: a follow-up study.

Diffusion-weighted (DWI) echo-planar (EPI) MRI has been used for imaging acute ischaemic stroke. We used DWI and conventional spin-echo (SE) MRI to study the dynamics of ischaemic human stroke. We examined 30 patients (mean age 57.5 years, range 27-82 years, median 57 years) with a diagnosis of stroke. They were examined in the acute (120 min to 47 h, mean 15.3 h), subacute (8 days) and chronic (2-3 months) stages of ischaemia using clinical scores and MRI. Imaging was performed on an 1.5-T imager. Anisotropic DWI with diffusion gradients in all three axes, an isotropic tensor trace pulse DWI sequence and SE MRI were used. In all patients both DWI sequences showed a decrease in the apparent diffusion coefficient (ADC) in the acute stage, even when SE images did not reveal signal abnormalities. Clinical features correlated with lesion site but not size. The ADC was initially 19.6-43% less than that of nonischaemic tissue and increased to normal after 7 days in conventionally treated patients and after 2-5 days in patients who underwent intra-arterial fibrinolysis. In the chronic stage the ADC rose by up to 254.4 %. In patients who did not undergo fibrinolysis DWI changes correlated with the final infarct size (P<0.05). It was possible to differentiate acute from chronic ischaemic lesions. We conclude that DWI is a sensitive and practicable tool for detecting early cerebral ischaemia. It is possible to predict in the acute stage the final size of an infarct. DWI may be helpful for clinical decisions and for monitoring therapy.

Brain↗
PubMed2000

Comparison of the ECST, CC, and NASCET grading methods and ultrasound for assessing carotid stenosis. European Carotid Surgery Trial. North American Symptomatic Carotid Endarterectomy Trial.

We compared three angiographic methods for grading of carotid stenosis and examined the correlation between angiographic and ultrasound findings. Two observers independently measured 111 carotid stenoses on arteriographic films of 84 patients. The stenoses were graded according to the European Carotid Surgery Trial (ECST), North American Symptomatic Carotid Endarterectomy Trial (NASCET), and Common Carotid (CC) methods. The results obtained by these methods were compared, and the interobserver reproducibility of the measurements was calculated. In addition, all angiographic results were compared to ultrasound findings obtained before angiography. Measurements using the CC method were the most reproducible and those using the NASCET method the least. The NASCET method underestimated the degree of stenosis compared to the other methods. The ECST and CC methods yielded almost identical results (97% agreement). Ultrasound provided an accuracy of 94% compared to ECST and CC methods and 84% compared to the NASCET method. Interobserver reproducibility of angiographic quantification of carotid stenoses was best for the CC and ECST methods and least for the NASCET method. Ultrasound demonstrated better accuracy than the ECST and CC methods.

Adult↗
PubMed2000

The formation and regression of a flow-related cerebral artery aneurysm.

The authors report a patient with an aneurysm of the right cerebral posterior communicating artery (PCoA) developing after thrombotic pseudo-occlusion of the right internal carotid artery (ICA). The aneurysm regressed spontaneously subsequent to ipsilateral ICA endarterectomy and reversal of blood flow in the PCoA. The formation and regression of the aneurysm was well documented by repeat cerebral digital subtraction angiography studies, computed tomography and magnetic resonance imaging. The authors conclude that the formation and regression of this 'flow-related' aneurysm was associated with hemodynamic changes in blood flow of the right PCoA and the right ICA.

Aged↗
PubMed2000

Abnormal myelination in a patient with deletion 14q11.2q13.1.

A male carrying an interstitial deletion of chromosome 14, presumably del(14)(q11.2q13), and presenting with abnormal myelination on magnetic resonance imaging is described. The abnormal myelination was evidenced as a high-signal intensity on T(2)-weighted magnetic resonance imaging. The patient had severe neurologic signs, various dysmorphic features, and a marked microcephaly. To our knowledge, this case is the first patient reported with abnormal myelination and a deletion of chromosome 14.

Child↗
PubMed2000

Swelling of the third nerve in a child with transient oculomotor paresis: a possible cause of ophthalmoplegic migraine.

Transient oculomotor nerve palsy is rarely observed in childhood and mostly is recognized to be a migraine equivalent. We report an 8-year old girl who presented with recurrent attacks of transient oculomotor paresis. The clinical profile of the patient suggested transient dysfunction in the context of an ophthalmoplegic migraine. A CT scan was normal, but MRI demonstrated a swollen right oculomotor nerve.

Child↗