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H Alvarez

Publications and source records attributed to H Alvarez.

At least 19 recordsLinked to original sources
PubMed2006

Multiple mirror-like intracranial aneurysms. Report of a case and review of the literature.

While multiple intracranial arterial aneurysms occur in 26.4% of patients with aneurysms, in our practice bilateral mirror-like aneurysms are encountered in 9.4% of patients. Multiple mirror aneurysms in the same patient are exceedingly rare. We report a case of mirror-like middle cerebral artery aneurysms associated with mirror-like posterior inferior cerebellar arteries aneurysms and discuss their significance. Although an exceptional finding, multiple mirror-like aneurysms may shed light on the vulnerability of different arterial segments to specific diseases.

Cerebellum↗
PubMed2006

Music for pain relief.

BACKGROUND: The efficacy of music for the treatment of pain has not been established. OBJECTIVES: To evaluate the effect of music on acute, chronic or cancer pain intensity, pain relief, and analgesic requirements. SEARCH STRATEGY: We searched The Cochrane Library, MEDLINE, EMBASE, PsycINFO, LILACS and the references in retrieved manuscripts. There was no language restriction. SELECTION CRITERIA: We included randomized controlled trials that evaluated the effect of music on any type of pain in children or adults. We excluded trials that reported results of concurrent non-pharmacological therapies. DATA COLLECTION AND ANALYSIS: Data was extracted by two independent review authors. We calculated the mean difference in pain intensity levels, percentage of patients with at least 50% pain relief, and opioid requirements. We converted opioid consumption to morphine equivalents. To explore heterogeneity, studies that evaluated adults, children, acute, chronic, malignant, labor, procedural, or experimental pain were evaluated separately, as well as those studies in which patients chose the type of music. MAIN RESULTS: Fifty-one studies involving 1867 subjects exposed to music and 1796 controls met inclusion criteria. In the 31 studies evaluating mean pain intensity there was a considerable variation in the effect of music, indicating statistical heterogeneity ( I(2) = 85.3%). After grouping the studies according to the pain model, this heterogeneity remained, with the exception of the studies that evaluated acute postoperative pain. In this last group, patients exposed to music had pain intensity that was 0.5 units lower on a zero to ten scale than unexposed subjects (95% CI: -0.9 to -0.2). Studies that permitted patients to select the music did not reveal a benefit from music; the decline in pain intensity was 0.2 units, 95% CI (-0.7 to 0.2). Four studies reported the proportion of subjects with at least 50% pain relief; subjects exposed to music had a 70% higher likelihood of having pain relief than unexposed subjects (95% CI: 1.21 to 2.37). NNT = 5 (95% CI: 4 to 13). Three studies evaluated opioid requirements two hours after surgery: subjects exposed to music required 1.0 mg (18.4%) less morphine (95% CI: -2.0 to -0.2) than unexposed subjects. Five studies assessed requirements 24 hours after surgery: the music group required 5.7 mg (15.4%) less morphine than the unexposed group (95% CI: -8.8 to -2.6). Five studies evaluated requirements during painful procedures: the difference in requirements showed a trend towards favoring the music group (-0.7 mg, 95% CI: -1.8 to 0.4). AUTHORS' CONCLUSIONS: Listening to music reduces pain intensity levels and opioid requirements, but the magnitude of these benefits is small and, therefore, its clinical importance unclear.

Analgesics, Opioid↗
PubMed2005

Hereditary hemorrhagic telangiectasia in children: endovascular treatment of neurovascular malformations: results in 31 patients.

Hereditary hemorrhagic telangiectasia (HHT) is a heterogeneous disease that can present with a variety of clinical manifestations. The neurovascular complications of this disease, especially in children, may be potentially devastating. The purpose of this article was to review the therapeutic results of endovascular treatment of neurovascular malformations in children. A total of 31 patients under the age of 16 were included in this retrospective analysis. All children were treated in a single center. Twenty children presented with 28 arteriovenous (AV) fistulae, including seven children with spinal AV fistulae and 14 children with cerebral AV fistulae (one child had both a spinal and cerebral fistulae). Eleven children had small nidus-type AV malformations. All embolizations were performed employing superselective glue injection. Follow-up ranged between 3 and 168 months (mean 66 months). A total of 115 feeding vessels were embolized in 81 single sessions, resulting in a mean overall occlusion rate of the malformation of 77.4% (ranging from 30 to 100%). Two of 31 patients (6.5%) died as a direct complication of the embolization procedure; two patients (6.5%) had a persistent new neurological deficit; eight patients (26.7%) were clinically unchanged following the procedure; in 13 patients (41.9%) an amelioration of symptoms but no cure could be achieved; and six patients (19.4%) were completely asymptomatic following the endovascular procedure. In the surviving patients morphological complete occlusion was possible in twelve patients (38.7%); therapy is still not completed in six patients. Since the natural history of neurovascular manifestations of HHT in children is associated with high morbidity and mortality, therapeutic intervention is mandatory. In most instances a morphological target can be identified; therefore, even partial and staged treatment can be performed. Our results demonstrate that in 27/31 patients these targeted interventions resulted in stabilizing the disease, ameliorating the symptoms or even complete resolution. The endovascular approach employing glue as the embolizing agent represents a safe and efficient way to control the neurovascular phenotypes of HHT.

Adolescent↗
PubMed2005

Neurovascular phenotypes in hereditary haemorrhagic telangiectasia patients according to age. Review of 50 consecutive patients aged 1 day-60 years.

Hereditary haemorrhagic telangiectasia (HHT) is inherited as an autosomal dominant trait with varying penetrance and expressivity. Some of the most devastating consequences of this disease result from cerebral vascular malformations that manifest themselves in either arteriovenous fistulae (AVF), small nidus-type arteriovenous malformations (AVM) or micro-AVMs with a nidus less than 1 cm in size. The purpose of this study was to compare the phenotypes of CNS-manifestations of HHT with the age of the patient. The charts and angiographic films of 50 patients diagnosed with HHT according to the Curaçao criteria were retrospectively evaluated concerning age of onset of symptoms, or, if not applicable of first consultation. The files were reviewed for clinical presentation, family and personal history, while the patients' angiograms were analysed with respect to the number of lesions (single and multiple), the location (superficial supratentorial, deep supratentorial, infratentorial, and spinal), and type of lesion (fistulous AVM, nidus-type AVM, and micro-AVM). A total of 75 central nervous system manifestations of HHT were found. Lesions included seven spinal cord AVFs that were all present in the paediatric age group (mean age: 2.2 years), 34 cerebral AV fistulae, all but two affected patients were less than 6 years (mean age 3.0). Sixteen nidus type AVMs (mean age: 23.1 years) and 18 micro-AVMs (mean age: 31.8 years) were found. HHT displays an age-related penetrance of clinical manifestations. Since members of the same family can present with completely different phenotypes of this disease there seems to be no relationship between the type of mutation and the phenotype of the disease. Since there seems to be a continuum of vascular abnormalities (from large fistulous areas to small AVMs and micro-AVMs) associated with HHT, the most likely determinating factor of the HHT phenotype is the timing of the revealing event in relation to the maturity of the vessel. Presumably, the trigger of the quiescent genetical abnormality transforms a "dormant" disease into a morphologically and therefore clinically detectable one by impairing a specific vessel segment at a specific (more or less vulnerable) period of time. The nature of this triggering event is, however, as of yet unclear.

Adolescent↗
PubMed2005

Supratentorial cerebral arteriovenous fistulas (AVFs) in children: review of 41 cases with 63 non choroidal single-hole AVFs.

PURPOSE: In this article we explore the various aspects of the supratentorial Single-Hole AVFs (ST AVFs) in children, focusing on their clinical features, angio-architecture, treatment indications and the role and results of endovascular management. MATERIALS AND METHODS: Among 1565 cases of brain AVMs seen at our neurovascular center, 620 cases were seen in the pediatric age group (<or= to 15 year-old) and 303/620 were non-Galenic brain AVMs. Among 52 brain AVFs found in children, we reviewed 41 pediatric patients with supratentorial single-hole cerebral AVFs (M/F=28/13) with a total of 63 AVFs. Mean age at presentation was 24 months. Four cases had their lesion diagnosed in utero without particular prognostic significance. 17 cases were multifocal with a total of 39 AVFs. The most common clinical presentation leading to diagnosis was cardiac sufficiency in (31.7%), epilepsy (24.4%), macrocrania (14.6%). Venous ectasia (87.8%) and pial venous stenosis (41.5%) were the most frequent angiographic features. There were 11 cases of Hemorrhagic Heriditary Telangiectasia (HHT1) (including two suspicious cases) among the 41 patients (26.8%) and among those 4 cases had single AVFs and 7 cases had multiple AVFs. RESULTS: Thirty-five children were treated in our institution: 34/35 by embolization alone, 1/35 by a combination of embolization and radiosurgery. 32/35 patients were treated with glue alone, 3/35 with coils (2/3 with glue also). A total of 57 separate lesions were treated. On clinical follow up (from 1985-2002, mean 4.2 years), 88.6% of patients proved to be either asymptomatic, improved from previous clinical symptoms or stabilized. 40% of patients had their lesion(s) already completely excluded. Post operative mortality was 5.6% (2/35), permanent neurological morbidity 3% (1/33). Twenty-six of these 33 patients (78.6%) were neurologically normal. 5/33 patients continue to have neurological symptoms or retardation. 2/33 patients died during follow up (1 ischemic stroke from Pulmonary AVF, 1 death despite partial embolisation). CONCLUSION: Cerebral arteriovenous fistulae are a rare disease, but not infrequently seen in neonates and infants with AVMs. In one fourth of these patients HHT is suspected to be present. The AVFs are always superficial and fed by pial (cortical) arteries. They seldom reveal a hemorrhagic event. They are similar to those encountered in the posterior fossa or spinal cord. Endovascular treatment using NBCA was the treatment modality chosen resulting in a high rate of success and allowing children to grow up normally with no hemorrhages on follow up and no new symptom other than those already present on admission.

Adolescent↗
PubMed2004

Posterior cranial fossa single-hole arteriovenous fistulae in children: 14 consecutive cases.

We report 14 consecutive children with 23 posterior cranial fossa arteriovenous fistula (AVF); six had multifocal lesions, involving the supratentorial brain in three and the spinal cord in one. There were two boys and four girls with a family history compatible with hereditary haemorrhagic telangiectasia. The diagnosis was made in infancy in eight cases and in a further six before the age of 12 years; mean age at diagnosis was 3.5 years. The male-to-female ratio was 1.8:1. Presenting features were macrocrania in four cases, haemorrhage or headache in three and nonhaemorrhagic neurological deficits or and cardiac overload in two. Dominant supply to the symptomatic fistula arose from the posterior inferior cerebellar artery in five cases, anterior inferior cerebellar artery in two and the upper basilar artery system in seven. All children were primarily treated by transarterial embolisation. We treated thirteen children (93%) by transarterial embolisation alone; one older child with a history of haemorrhage also underwent radiosurgery. We obtained 100% exclusion of the fistula(e) in six children, 95-80% in five, 80-50% in one and <50% in one. Of the incompletely treated cases, three had conservative management, and two with 80% and one with 60% reduction of their lesion are scheduled for elective treatment; two partially treated case died. There was no morbidity due to the endovascular procedures. Follow-up since referral is 6 months-10 years (mean 4.5 years). Ten children are neurologically normal, two have persistent (pre-existing) neurological deficits and two are dead.

Arteriovenous Fistula↗
PubMed2004

Bilateral segmental regression of the carotid and vertebral arteries with rete compensation in a Western patient.

We report a case of symptomatic symmetrical, bilateral absence of the cavernous internal carotid (ICA) and transdural vertebral artery (VA) segments with formation of a rete mirabile. There have been similar reports in Asian patients; ours is the first in the Western population. A 29- year-old woman presented with recurrent temporary blindness and an episode of minor subarachnoid haemorrhage. Angiography demonstrated absence of the C5 and C6 segments of the ICA and the C1/2 segments of the VA bilaterally, with typical carotid rete mirabile formation to reconstitute the distal flow. Comparative anatomy and embryology show retia in several species and point to their secondary origin. The anomalies of the ICA cannot be called agenesis but rather absence since they are likely to result from perinatal disappearance of the artery rather its failure to develop.

Adult↗
PubMed2004

Angio-architecture of spinal cord arteriovenous shunts at presentation. Clinical correlations in adults and children. The Bicêtre experience on 155 consecutive patients seen between 1981-1999.

OBJECTIVE: To analyse possible relationships between the symptoms and signs created by intradural spinal cord arteriovenous shunts (SCAVSs) and their angio-architecture. METHODS: The clinical and radiological files of 155 patients, both adults and children, seen between 1981 and 1999 with a SCAVS were retrospectively reviewed. SCAVSs were divided into nidus type (small superficial or large intramedullary), and fistulas (micro (mAVFs)- or macrofistulas (MAVFs)). The angio-architectural points studied were arterial stenosis, proximal arterial aneurysm, distal arterial aneurysm, arteriovenous fistulas, pial venous drainage and/or reflux, venous ectasias, venous stenosis, venous thrombosis, false aneurysms. Correlations between architecture, location, age groups and symptoms and signs were made. FINDINGS: A male predominance was noted in both adults and children. Most of the lesions were located at the thoracic level, but hemorrhage occurred as the presenting event predominantly in cervical localizations. 30 patients (20 AVMs; 4 mAVFs, 6 MAVFs) were children. 5 of the 6 MAVFs found in children were associated with Hereditary Hemorrhagic Telengiectasia (HHT1). Twenty one children (70%) had bled. Spontaneous total or subtotal recovery was the rule in 15 of those who had bled (72%) but early recurrent hemorrhages occurred in 2. Among 125 adults 56 presented with hemorrhage (45%). The proportions of those who recovered spontaneously (71%) or rebled (3,6%) in the same year after the initial episode were very similar to children. All other adults presented with acute or progressive non-hemorrhagic episodes. There was no significant difference in the angio-architecture between hemorrhagic and non hemorrhagic SCAVS, except for that occurrence of pseudo-aneurysms. Hemorrhage in SCAVSs may not be exclusively due to haemodynamic factors. Venous congestion was responsible for progressive symptoms. Acute deficits unrelated to bleeds were due to intralesional thrombosis or hemodynamic changes. INTERPRETATION: The short term prognosis of hemorrhagic SCAVSs is good, and there is no need for emergency treatment. MRI delineates the cord and makes the diagnosis of the lesion but angiography remains the gold standard for analysis of the vasculature. The angio-architecture reflects the ageing of the lesion but there is not a precise correlation between angio-architecture and clinical symptoms, except for pseudoaneurysms which relate to the hemorrhagic portion of the lesion.

Adolescent↗
PubMed2004

PHACES syndrome: a review of eight previously unreported cases with late arterial occlusions.

PHACE and PHACES are acronyms for a syndrome of variable expression comprising posterior cranial fossa malformations, facial haemangiomas, arterial anomalies, aortic coarctation and other cardiac disorders, ocular abnormalities and stenotic arterial disease. We review five girls and three boys aged 1 month-14 years with disorders from this spectrum. Six had large facial haemangiomas but recent reports suggest that small haemangiomas may occur; hence our inclusion of two possible cases. We also focus on the recently recognised feature of progressive intracranial arterial occlusions, present in four of our patients, later than previously recognised, from 4 to 14 years of age. We suggest that many elements of this disorder could reflect an abnormality of cell proliferation and apoptosis.

Adolescent↗
PubMed2004

[Histopathological changes at the surgical site in experimental animals following partial cricoid resection and thyrotracheal anastomosis].

OBJECTIVE: To study in an animal model the local healing process after partial cricoid resection with thyrotracheal anastomosis. MATERIAL AND METHODS: Partial cricoid resection with thyrotracheal anastomosis was performed in 17 New Zealand rabbits. Experimental animals were gradually sacrificed and the laryngotracheal complex was removed to proceed to a histopathological study. RESULTS: An acute inflammatory response followed by a chronic inflammatory process was found in the surgical site. Normal tissue architecture was established after an eight week period. Anteroposterior and transverse diameters at all levels of the upper respiratory tract were not significantly altered at any time along the healing process. Experimental animals remained free from symptoms during the follow-up period. CONCLUSIONS: These results support that partial cricoid resection with thyrotracheal anastomosis is a safe procedure for the treatment of severe laryngotracheal stenosis.

Anastomosis, Surgical↗
PubMed2003

Craniofacial arteriovenous metameric syndrome (CAMS) 3--a transitional pattern between CAM 1 and 2 and spinal arteriovenous metameric syndromes.

We report a rare case of craniofacial arteriovenous metameric syndrome (CAMS) 3 arteriovenous malformations of the mandible, left VIII nerve and petrous bone. The patient, a 19-year-old girl, presented with profuse gingival bleeding during a dental procedure and we diagnosed CAMS 3 during a pre-embolisation angiogram. The distribution of the vascular lesions suggests that CAMS 3 is intermediate CAMS 1 and 2 and spinal arteriovenous metameric syndrome (SAMS).

Adult↗
PubMed2002

Severe cardiac failure in newborns with VGAM. Prognosis significance of hemodynamic parameters in neonates presenting with severe heart failure owing to vein of Galen arteriovenous malformation.

OBJECTIVE: Neonatal vein of Galen malformation complicated by severe cardiac failure is a rare disease. The purpose was to assess the outcome of this life-threatening malformation and identify hemodynamic prognostic factors. DESIGN: Retrospective study. PATIENTS: Twenty-four newborns with cardiac failure requiring mechanical ventilation were consecutively admitted from 1986 to 2000. INTERVENTIONS: Cardiovascular evaluation including echocardiogram was performed in all cases. Eighteen transarterial shunt occlusions with glue were applied by the same team of three physicians. MEASUREMENTS AND RESULTS: Twelve babies survived and underwent one endovascular session at least (median age 20 days) with a mean 63 months follow-up. Embolization was not performed in 6 of the 12 nonsurvivors because of severe brain damage or profound hypotension Cardiogenic shock occurred in all nonsurvivors, but also in one long-term survivor (p<0.0001). Echocardiogram showed signs of right ventricular failure, most often in the dead babies (p=0.005). The pulmonary systemic arterial pressure ratio was significantly higher in the nonsurvivor group (p=0.031), and it decreased significantly after the first embolization only in patients who survived (p=0.01). Patent ductus arteriosus and a diastolic aortic reversed-flow were present in all nonsurvivors in contrast to 30% of the long-term survivors (p=0.003 ). There was no difference in the left ventricular contractility and mean cardiac output between the two groups. CONCLUSIONS: The outcome of vein of Galen malformation complicated by severe cardiac failure requiring mechanical ventilation remains poor. Neonatal embolization seems to be beneficial only in babies without suprasystemic pulmonary hypertension.

Arteriovenous Malformations↗
PubMed2002

Effect of partial targeted N-butyl-cyano-acrylate embolization in brain AVM.

BACKGROUND: The management of cerebral arteriovenous malformations needs effective treatments. So far, no study has shown that partial targeted embolization treatment (PTET) reduces the risk of intracranial hemorrhage with respect to the natural history of the malformation. METHODS: The pre-treatment and post-treatment-initialization hemorrhage incidences of neuro-interventional patients were compared. Two hundred fifteen patient years from 519 patients were used to observe the short term course of the untreated disease. Five hundred patient years from 326 patients were used to observe hemorrhage after the start of treatment. The Kaplan-Meier estimator of hemorrhage free time under treatment was compared with results in the literature. Confounding influences resulting from selection processes or the disease parameters were studied. RESULTS: The yearly hemorrhage incidence rate of all untreated patients was observed as 0.089 (95% CI [0.053, 0.138]). This rate was 0.052 (95% CI [0.019, 0.114]) in the subgroup of patients who underwent PTET later. In the same group the observed annual rate after the start of PTET was 0.036 (95% CI [0.021, 0.057]). Crawford's results about intracranial hemorrhage during the natural course show the lowest risk values compared to other published studies [3]. There was a significant difference between the Crawford's reference data and the ICH incidence after the start of PTET in the neuro-interventional population (p=0.037). The morbidity risk in treated patients was 5.3% for a transitory and 2% for a persisting neurological deficit. Mortality results were compared with those of Crawford. CONCLUSION: The neuro-interventional patients under study show a lower hemorrhage risk than the population studied by Crawford. A significant superiority with respect to hemorrhage risk is established two years after the start of the PTET treatment.

Adolescent↗
PubMed2001

Genome-wide allelotyping analysis reveals multiple sites of allelic loss in gallbladder carcinoma.

Although gallbladder carcinoma (GBC) is a highly malignant neoplasm, there is very limited information about the molecular changes involved in its pathogenesis. To identify the chromosomal locations of putative tumor suppressor gene loci involved in the pathogenesis of GBC, we conducted a genome-wide allelotyping or loss of heterozygosity (LOH) analysis of GBCS: Microdissected tissue from 24 archival GBCs and their matched control DNAs were analyzed for PCR-based LOH using 169 microsatellite markers spanning all nonacrocentric autosomal arms and the X chromosome. The chromosomal arms with the greatest frequencies of LOH (> or = 60%) were 3p, 6q, 7q, 8p, 9p, 9q, 11q, 12q, 17p, 18q, 19p, 22q, and XQ: The average fractional allele loss index in GBC cases was high (0.43) and frequent breakpoints were detected in gallbladder tumors. Of interest, 21 different regions of frequent LOH (hot spots) defined as > or = 50% for individual GBC samples were detected in this neoplasm, nearly half of them confined to one microsatellite marker. We conclude that in GBC at least 21 chromosomal regions with frequent allele losses are involved, suggesting that several putative tumor suppressor genes are inactivated in its pathogenesis. Overall, these data provide global estimates of the extent of genetic changes leading to GBC and will be useful for the identification of new tumor suppressor genes and for multiple new markers for translational research.

Adenocarcinoma↗
PubMed2001

Intracranial haemorrhage within the first two years of life.

BACKGROUND: Spontaneous intracranial haemorrhage is not common in infants, with differences from adults in both aetiology and severity. The infantile CNS is more vulnerable because of incomplete hydrovenous maturation. We analyzed infantile intracranial haemorrhage mainly caused by structural brain lesions and discuss specific aetiologies with regard to haemodynamic characteristics. SUBJECTS AND METHODS: We reviewed 20 infants less than 2 years of age from a total of 328 neonates and infants with intracranial vascular lesions seen in our institution since 1985. Associated or causative lesions were arteriovenous malformation (AVM) in 6, dural sinus malformation (DSM) in 4, arteriovenous fistula (AVF) in 3, aneurysm in 2, developmental venous anomaly (DVA) in 1, vein of Galen malformation (VGAM) in 1, and others in 3. The locations of haematomas were intracerebral (ICH) in 8, combined ICH and intraventricular haemorrhage (IVH) in 5, IVH alone in 5, subarachnoid haemorrhage (SAH) in 1, and combined SDH and ICH in 1. FINDINGS: Three patterns of haemorrhage were noted in high-flow vascular lesions such as AVM or AVF (n=9); haemorrhage at the site of nidus or fistula corresponding to nidal pseudoaneurysm in 4, regional venous hypertension with pial venous reflux in 3, global venous infarction causing multifocal haemorrhage in distant brain areas in 2. Aneurysmal bleeds were caused by dissecting aneurysms at the level of dural penetration of cranial vessels. One infant had haemorrhage near a DVA without evidence of cavernous malformation suggesting the possibility of venous ischaemia. IVH was associated with shunt operations in 4 infants with DSM, and SDH followed by ICH in a infant with VGAM. INTERPRETATION: Spontaneous intracranial haemorrhage in infants and neonates is rare; it is associated with specific lesions which show some differences from their adult counterparts. The vein-related causes of hemorrhage are largely the pathophysiologic characteristics in this age group. Absence of hemorrhage in VGAM is remarkable in addition to occurrence of most hemorrhages after shunting.

Arteriovenous Fistula↗
PubMed2000

Sequelae after nasal septum injuries in children.

OBJECTIVE: To study the results of surgical treatment and sequelae in nasal septum injuries in children. METHODS: Between January 1990 and December 1997, 16 pediatric patients with septal haematoma and/or abscess were treated. Mean age was 5 years (range: 2-14 years). Thirteen were male (81.2%), and three were female (18.8%). In nine cases (56.2%) the disease was a consequence of a minor trauma. Only two children had nasal fracture associated (12.5%). Minimum follow-up after the first visit was 10 months (mean, 3 years). RESULTS: All cases were surgically treated. Minor sequelae were observed in six cases (37.5%), and major ones in ten patients (62.5%). In this latter group, multiple reconstructive procedures were needed. CONCLUSIONS: It is necessary to be aware of the possibility of haematoma and abscess of the nasal septum. Major sequelae can be also expected after cases following minor traumas.

Abscess↗