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Biomedical subjects

L Remonda

Publications and source records attributed to L Remonda.

At least 37 records · Page 2Linked to original sources

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↗

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↗

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↗

Evaluation of the Contribution of CAS in Combination with the Subcranial/Subfrontal Approach in Anterior Skull Base Surgery.

In this study, 31 cases with different anterior skull base lesions mandating broad exposure, including the sphenoidal, parasellar, and clival region, were surgically treated using the frameless computer assisted surgery (CAS) system. The contribution of navigated surgery in relation to the broad exposure and direct visualization of this region rendered by the subcranial-subfrontal approach was evaluated. In group I, consisting of extensive tumors, the contribution of CAS was only given in five cases for the exposure of the tumor extensions located to the parasellar sphenoclival complex with concomitant distortion of the anatomic landmarks. No advantages were experienced in the more anterior locations along the ethmoidal compartment and frontal sinus. In the cases in group II, consisting of congenital anomaly implying fronto-orbital advancement and a meningoencephalocele as well as extensive mucoceles, the CAS was only helpful in those cases with an extremely aberrative anatomy in these regions.

Journal Article↗

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↗

[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↗

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↗

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↗

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↗

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↗

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↗

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↗

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↗

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↗

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↗

Silent cerebral ischemia detected by diffusion-weighted MRI after carotid endarterectomy.

BACKGROUND AND PURPOSE: Small emboli arising from a friable plaque during carotid endarterectomy (CEA) constitute an important risk of perioperative ischemic complications. To evaluate the incidence and significance of silent cerebral ischemic lesions of embolic origin after CEA, we prospectively examined a series of surgical patients with high-grade carotid stenosis by using diffusion-weighted MRI (DWI). We also tried to correlate postoperative ischemic lesions with the occurrence of sonographic cerebral embolic signals, the presence of plaque ulcerations, and the use of intraoperative shunting. METHODS: Of a consecutive series of 53 patients undergoing elective CEA for high-grade carotid stenosis, 48 patients with unchanged postoperative neurological status were prospectively studied with DWI of the brain the day before and the day after the operation. The magnetic resonance images were analyzed by 2 neuroradiologists blinded to the clinical result of the operation. Any new hyperintense signal was interpreted as a postoperative ischemic lesion. RESULTS: Forty-six (95.8%) of 48 patients had unchanged postoperative brain DWI. In 2 patients (4.2%), a new single asymptomatic hyperintense signal was observed on the side of the operation. Both lesions were small and presumably of embolic origin. They were not related to sonographic embolic signals, plaque ulcerations, or intraoperative shunting. CONCLUSIONS: These results suggest that the incidence of silent ischemic brain lesions of embolic origin after CEA is low and does not correlate with the occurrence of intraoperative sonographic microemboli. They confirm that CEA is a safe procedure that carries a low risk of postoperative cerebral events.

Aged↗

Pleomorphic xanthoastrocytoma derived from glioneuronal malformation in a child with intractable epilepsy.

Malformative lesions as well as neoplasms can cause intractable epilepsy in childhood. Even though the neoplastic nature of a lesion is evident in most cases, the distinction can be difficult in some patients. We present the case of a child with intractable epilepsy caused primarily by a glioneuronal malformation. Years after the first surgical intervention, a pleomorphic xanthoastrocytoma evolved from remnants of this lesion. This case suggests that glioneuronal malformations might be precursor lesions of pleomorphic xanthoastrocytomas.

Astrocytoma↗