Search PubMed⌕ Search

Biomedical subjects

G Guglielmi

Publications and source records attributed to G Guglielmi.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Comparison of mammographic and industrial films in dialysis patients].

PURPOSE: To optimize the technique for radiographic studies of bone and joint damage in renal osteodystrophy. MATERIAL AND METHODS: Sixty-four patients with chronic renal failure on dialysis for 0-10 years, were divided into two homogeneous groups and submitted to two different radiographic examinations of the nondominant hand. Group A patients were examined with a conventional radiological unit and an industrial film and a conventional radiological unit with a mammographic film with a dedicated screen, while group B patients with a mammographic with an industrial film and a conventional radiologic unit with a mammographic film with a dedicated screen. The examinations were evaluated by three radiologists in a double-blind fashion. RESULTS: Bone conditions such as osteoporomalacia, trabecular rarefaction, channel enlargement and intracortical absorption were equally demonstrated by mammographic films and the mammograph with industrial films. The mammographic film was superior to the mammograph with an industrial film in 8 cases, comparable in 25 and inferior in 6, but when compared with the conventional radiological unit with an industrial film it was superior in 19 cases, comparable in 2 and never inferior. CONCLUSIONS: The industrial film without a screen combined with a mammograph is considered the gold standard to study fine bone alterations in renal osteodystrophy. However the conventional radiological unit with a mammographic film with a dedicated screen provides the same results with lower irradiation doses and can therefore be considered a good alternative.

Adult↗
PubMed2000

Endovascular treatment of basilar tip aneurysms using Guglielmi detachable coils: anatomic and clinical outcomes in 73 patients from a single institution.

OBJECTIVE: Seventy-three consecutive patients with 75 basilar tip aneurysms were treated with Guglielmi detachable coil (GDC) technology. Their anatomic and clinical outcomes are discussed. METHODS: Seventy-five basilar tip aneurysms were treated with the GDC system at the University of California, Los Angeles Medical Center from 1990 to 1999. The average age of the population was 48.3 years (range, 28-82 yr). Forty-two patients (57.5%) presented with acute subarachnoid hemorrhage, 8 patients (10.9%) had unruptured aneurysms with mass effect, and 23 patients (31.5%) had incidental aneurysms. Thirty-one aneurysms (41.3%) were small with a small neck, 18 (24%) were small with a wide neck, 16 (21.3%) were large, and 10 (13.3%) were giant aneurysms. RESULTS: Immediate anatomic outcomes demonstrated complete or near-complete occlusion in 64 aneurysms (85.3%) and incomplete occlusion in 7 aneurysms (9.3%). Four aneurysms (5.3%) could not be embolized because of anatomic difficulties. Of the 69 patients treated with GDCs, 63 patients (91.3%) remained neurologically intact or unchanged from their initial clinical status. Procedure-related morbidity and mortality were 4.1% and 1.4%, respectively. Long-term follow-up angiograms were obtained in 41 patients with 42 aneurysms. Thirty aneurysms (71.4%) demonstrated complete or near-complete occlusion. One incompletely embolized giant aneurysm ruptured during the follow-up period. CONCLUSION: In contrast to surgical clipping of basilar tip aneurysms, the main technical challenge of the Guglielmi detachable coiling procedure depends on the shape of the aneurysm, not its location. The results of this study indicate that endovascular GDC technology is an appropriate therapeutic alternative in ruptured or unruptured basilar tip aneurysms regardless of patient age, clinical presentation, clinical status, or timing of treatment.

Adult↗
PubMed1999

Phalangeal US velocity discriminates between normal and vertebrally fractured subjects.

The purpose of this study was to evaluate the diagnostic sensitivity of phalangeal bone ultrasound velocity of the hand in the diagnosis of osteoporosis and to compare this technique to bone mineral density (BMD) measurement at the lumbar spine assessed by dual X-ray absorptiometry (DXA) and quantitative computed tomography (QCT). We investigated US velocity at the distal metaphysis of the proximal phalanx and spinal BMD in 101 women. Fifty-nine were healthy (mean age 50 +/- 11.6 years) and 42 were osteoporotic (mean age 65 +/- 6.6 years) with documented vertebral fractures. In the healthy population the relation with age was, respectively, r = -0.73 (p < 0. 0001) for quantitative US (QUS), r = -0.74 (p < 0.0001) for QCT and r = -0.48 (p < 0.01) for DXA. Both US and DXA were correlated with QCT: r = 0.74 and r = 0.77 (p < 0.0001), respectively. Correlation of QUS and DXA was r = 0.56 (p < 0.0001). Phalangeal US velocity and spinal BMD (QCT and DXA) values discriminate healthy from osteoporotic women. Age-adjusted logistic regression analysis of the data showed standardized odds ratios (OR) for vertebral fracture to be similar for US and DXA (OR = 1.8 and 1.5, respectively) and stronger for QCT (OR = 2.9). Phalangeal US velocity reflects age-related bone loss and differentiates between healthy and osteoporotic subjects.

Absorptiometry, Photon↗
PubMed1999

Imaging of trabecular bone structure in osteoporosis.

Osteoporosis is a metabolic bone disorder that is characterized by reduced bone mass and a deterioration of bone structure which results in an increased fracture risk. Since the disease is preventable, diagnostic techniques are of major importance. Standard techniques determine bone mineral density, whereas some of the newer techniques focus on trabecular structure. This article reviews structure analysis techniques in the diagnosis of osteoporosis. Imaging techniques applied to the assessment of trabecular bone structure include conventional radiography, magnification radiography, high-resolution CT (HRCT) and high-resolution MR imaging (HRMRI). The best results were obtained using high-resolution tomographic techniques. The highest spatial resolutions in vivo were achieved using HRMRI. The most common texture analysis techniques that have been used are morphological parameters (analogous to bone histomorphometry). Fractal dimension, co-occurrence matrices, mathematical filter techniques and autocorrelation functions are more complex techniques. Most of the studies evaluating structure analysis show that texture parameters and bone mineral density both predict bone strength and osteoporotic fractures, and that combining both techniques yields the best results in the diagnosis of osteoporosis.

Bone Density↗
PubMed1999

Ballonn-assisted Guglielmi detachable coiling of wide-necked aneurysma: Part II--clinical results.

OBJECTIVE: To demonstrate the indications and efficacy of balloon-assisted Guglielmi detachable coiling (BAGDC). METHODS: BAGDC was used for 23 patients (19 women and 4 men; mean age, 55 yr) (17%) of a series of 136 consecutive patients who underwent Guglielmi detachable coiling of aneurysms. Every aneurysm had a wide neck, and 57% were large (11-25 mm in diameter). In each case, a nondetachable silicone balloon was advanced in the parent artery and inflated to occlude the neck of the aneurysm and stabilize the Guglielmi detachable coil delivery microcatheter at the aneurysm neck. Guglielmi detachable coils were then deposited. The balloon was then deflated to verify appropriate coil placement and stability, and finally, the Guglielmi detachable coils were detached. This process was repeated until the aneurysm was suitably embolized. RESULTS: One hundred percent aneurysm embolization was achieved in 19 patients (83%), and 95 to 100% embolization was achieved in 4 patients (17%). Twenty-two patients (96%) were at their preprocedure neurological baseline after the procedure. There were three complications in the study. One patient died after sustaining subarachnoid hemorrhage-induced vasospasm followed by a hemorrhagic infarction. She had undergone an unsuccessful clip ligation of her aneurysm. A second patient developed an intra-arterial thrombus at the site of balloon deployment. She sustained ischemic events that were treated with thrombolysis and anticoagulation. She made a complete recovery. A third patient developed an intra-arterial thrombus that was noted during the procedure. She was treated with intra-arterial thrombolysis and experienced no clinical sequelae. No permanent complications could be attributed to the BAGDC technique. The median clinical follow-up time was 10 months. No patient required additional treatment or developed a recurrent aneurysm neck or lumen. CONCLUSION: BAGDC is a promising adjunct to the treatment of wide-necked aneurysms. The balloon serves two purposes: it stabilizes the microcatheter in the aneurysm during coil delivery, and it forces the coil to assume the three-dimensional shape of the aneurysm without impinging on the parent artery.

Adult↗
PubMed1999

Altered bone mass and turnover in female patients with adrenal incidentaloma: the effect of subclinical hypercortisolism.

The strategy of treatment for patients with adrenal incidentalomas (AI) may depend upon the presence of hormonal hypersecretion. Although alterations of bone turnover have been recently reported, data on bone mineral density (BMD) are not available in AI patients. We evaluated bone turnover and BMD in 32 female AI patients and 64 matched controls. Spinal and femoral BMD were similar in patients and controls. Serum bone GLA protein (6.8+/-3.5 vs. 8.8+/-3.2 ng/mL; P<0.005) and PTH (48.8+/-15.1 vs. 37.2+/-10.9 pg/mL; P<0.0001) were different in patients and controls. Patients were then subdivided into 2 groups: with (n = 8; group A) or without (n = 24; group B) subclinical hypercortisolism. PTH was higher (P<0.05) in group A than in group B and in both groups than in controls (57.1+/-13.6, 46.0+/-14.8, and 37.2+/-10.9 pg/mL, respectively), and bone GLA protein was lower in group A than in group B and controls (3.8+/-2.3, 7.5+/-3.1, and 8.8+/-3.2 ng/mL, respectively; P<0.05). Serum type I cross-linked C telopeptide and fasting urinary deoxypyridinoline/ creatinine were not different in the three groups. BMD at each site was lower (P<0.05) in group A than in group B and controls. Bone mass and metabolism are altered in AI patients with subclinical hypercortisolism and should be taken into account, therefore, when addressing the treatment of choice for these patients.

Adrenal Gland Neoplasms↗
PubMed1999

Embolization of incidental cerebral aneurysms by using the Guglielmi detachable coil system.

OBJECT: Guglielmi detachable coil (GDC) technology is a valuable therapeutic alternative to the surgical treatment of ruptured or incidental intracranial aneurysms. The authors describe their technical and clinical experience in the use of the GDC technique in patients who underwent endovascular occlusion for the treatment of incidentally found intracranial aneurysms. METHODS: One hundred fifteen patients with 120 incidentally found intracranial aneurysms underwent embolization by means of the GDC endovascular technique. Ninety-one patients were females and 24 were males. Patient age ranged from 13 to 80 years. In 64 patients the incidental aneurysms were discovered when unrelated nonneurological conditions signaled the need for angiography or magnetic resonance angiography (Group 1). Twenty patients who presented with incidental aneurysms that were discovered during treatment for an acutely ruptured aneurysm underwent treatment of both types of aneurysm during the acute phase of subarachnoid hemorrhage (SAH) (Group 2). Sixteen patients with incidental aneurysms were treated during the chronic phase of SAH (Group 3). Group 4 included 15 patients who had incidental aneurysms associated with brain tumors or arteriovenous malformations. Angiographic results revealed complete or near-complete occlusion in 109 aneurysms (91%) and incomplete occlusion in five aneurysms (4%). Guglielmi detachable coil embolization was attempted unsuccessfully in six aneurysms (5%). One hundred nine patients (94.8%) remained neurologically intact or unchanged from their initial clinical status. Five patients (4.3%) deteriorated as a result of immediate procedural complications. All these complications occurred in the first 50 patients treated in the series. No clinical complications were observed in the last 65 patients. In one patient, a partially embolized aneurysm ruptured 3 years postprocedure. In Groups 1 and 3, the average length of hospitalization was 3.3 days. CONCLUSIONS: The evolution of GDC technology has proved to provide safe treatment of incidental aneurysms (a morbidity rate of 0% was achieved in the last 65 patients). The topography of the aneurysm and the clinical condition of the patient did not influence final anatomical or clinical outcomes. The GDC technology also confers a positive economic impact by decreasing hospital length of stay and by eliminating the need for postembolization intensive care.

Adolescent↗
PubMed1999

Endovascular treatment of multiple intracranial aneurysms by using Guglielmi detachable coils.

OBJECT: The purpose of this paper is to present the authors' experience with Guglielmi detachable coil (GDC) embolization of multiple intracranial aneurysms and to evaluate the results of this therapy in single-stage procedures. METHODS: Clinical and angiographic evaluations were performed in 38 consecutive patients with multiple intracranial aneurysms treated by GDC embolization between March 1990 and October 1997. Twenty-nine patients presented with subarachnoid hemorrhage (SAH), four with mass effect, and five were asymptomatic. These 38 patients harbored 101 aneurysms, 79 of which were treated with GDCs, 14 by surgical clipping, and eight were left untreated. Of the GDC-treated lesions, a complete endovascular occlusion was achieved in 55 aneurysms (70%), and 24 (30%) presented neck remnants. Twenty-five patients (66%) underwent GDC embolization of more than one aneurysm in the first session. Eighteen (86%) of 21 patients with acute SAH underwent treatment for all aneurysms within 3 days after admission (15 of 21 in one session). Follow-up angiographic studies in 30 patients demonstrated an unchanged or improved result in 94% of the aneurysms (59 lesions) and coil compaction in 6% (four lesions). The overall clinical outcome was excellent in 34 patients (89%), good in one (3%), fair in one (3%), and death in two (5%). CONCLUSIONS: Endovascular treatment of multiple intracranial aneurysms, regardless of their location, with GDCs was performed safely in one session, even during the acute phase of SAH. Treatment of all aneurysms in one session protected the patient from rebleeding and eliminated the risk of mistakenly treating only the unruptured aneurysms.

Adolescent↗
PubMed1999

Osteochondroma of the L-5 vertebra: a rare cause of sciatic pain. Case report.

Solitary or multiple osteochondromas, which are benign bone tumors that usually occur in the long bones, are rarely found in the vertebral column. When present in the spine, however, they have a predilection for the cervical or upper thoracic regions. The authors present the case of a solitary osteochondroma arising from the left L-5 articular process that contributed to sciatica; complete cure was achieved following its removal. It is possible to speculate that the cartilage of secondary ossification centers can be the origin of aberrant islands of cartilaginous tissue that cause the osteochondroma to form. The more rapid the ossification process of these centers, the greater the probability that aberrant cartilage will form. Therefore, the fact that osteochondromas are more frequently located in the higher segments of the vertebral column could be explained by the different durations of the ossification processes in these centers, which increase gradually below the cervical segments.

Adult↗
PubMed1999

[Digital film viewer versus conventional view boxes in the identification of bone and joint disorders].

PURPOSE: To compare the diagnostic accuracy of a digital film viewer (Smartlight 2000 Plus) versus a conventional view box for the identification of bone and joint disorders. MATERIAL AND METHODS: In order to evaluate the qualitative and quantitative differences of digital and conventional film viewers, 100 plain films of patients with bone and joint disorders taken in an emergency room January through May 1998 were reviewed utilizing both types of view boxes. Three radiologists expert of bone and joint disorders, independently compared the films, filled a form about the qualitative and quantitative analysis of the lesions depicted for each patient, and reported a few notes on the technical quality of the plain films in terms of exposure. The results were compared using the chi-square test (p < 0.005). RESULTS: Data analysis showed that the digital film viewer permitted a quicker reading of the film while decreasing the perception threshold for elementary lesions and ocular fatigue. All the radiographs read with the digital film viewer were considered technically adequate: the film quality was considered good in 10 cases and sufficient in 2. Two of the same radiographs read with the conventional view box were considered of good quality, nine were considered sufficient and one was considered insufficient due to overexposure. There were six cases of agreement and six of disagreement for the diagnosis: four were due to overexposure of the radiograph and two to better conspicuity provided by the digital film viewer. DISCUSSION: Correct image illumination is the first element a radiologist evaluates when reading a radiograph. A conventional view box may, when it is not properly maintained or when the radiograph is overexposed, decrease the radiologist's visual capacity. This increases the time required to read the radiograph and, therefore, physical and ocular fatigue, which in turn increases the risk of missing or misevaluating a lesion. A digital film viewer emits light with a variable intensity which is proportional to the optical density of the film. This increases the visual capacity of the radiologist and the lesion contrast, while reducing the factors which affect the radiograph reading. CONCLUSIONS: The use of a digital film viewer increased the visual capacity of the radiologist and eliminated the negative elements which complicated the radiograph reading and permitted the use of radiographs that would otherwise have been considered of poor quality due to overexposure. This, combined with the experience of the radiologist, decreased of the risk of missing or misevaluating a lesion.

Bone Diseases↗
PubMed1998

Cellulase and hemicellulase genes of Clostridium thermocellum from five independent collections contain few overlaps and are widely scattered across the chromosome.

Five independent collections, comprising a total of 34 clones encoding cellulases, hemicellulases and cell surface proteins of Clostridium thermocellum, were searched for overlapping or contiguous DNA fragments. The clones were hybridized to large genomic restriction fragments separated by pulse-field electrophoresis. Clones hybridizing to the same fragment were further compared by hybridization to smaller fragments, by cross-hybridization and by restriction mapping. The probes hybridized to loci which were usually not clustered and were scattered over at least one third of the chromosome. Besides previously identified clusters, only two clones were found to be adjacent. Two pairs of clones appeared to contain the same genes cloned in duplicate, and one of the genes was shown to be cloned in triplicate.

Cellulase↗
PubMed1998

Diffuse idiopathic skeletal hyperostosis.

OBJECTIVE: To describe the axial and appendicular skeleton findings of diffuse idiopathic skeletal hyperostosis. To analyze the role of conventional radiography, computed tomography (CT) and magnetic resonance imaging (MRI) in the diagnosis of this condition. To discuss the differential diagnosis and diagnostic pitfalls of this disease. MATERIAL AND METHODS: The involvement of vertebral and extravertebral sites including the pelvis, calcaneum, ulnar olecranon, and patella is frequently found in the literature. The lesions described are the anterior and lateral ossification of the spine, hyperostosis at sites of tendon and ligament insertion, ligamentous ossification, and periarticular osteophytes. The criteria for the diagnosis of diffuse idiopathic skeletal hyperostosis involving the spine are: flowing ossification along the anterior and anterolateral aspects of at least four contiguous vertebrae, preserved intervertebral disc height, no bony ankylosis of the posterior spinal facet joints, and finally no erosion, sclerosis or bony ankylosis of the sacroiliac joints. RESULTS: The disease has about the same frequency in men (65%) and women (35%); it is most common in the thoracic spine and occurs less frequently in the lumbar and cervical spine. The disease most commonly presents in the sixth and seventh decades of life and its estimated frequency in the elderly is 5-15%. Signs and symptoms include stiffness and pain in the back, dysphagia due to direct esophageal compression/distorsion, pain related to associated tendinitis, myelopathy related to core compression associated to the ossification of the posterior longitudinal ligament, and pain related to vertebral complications--e.g. fracture/subluxation. CONCLUSION: While conventional radiography clearly confirms the diagnosis of diffuse idiopathic skeletal hyperostosis, CT and MRI better detect associated findings (e.g. ossification of the posterior longitudinal ligament) and complications (e.g. spinal cord compressive myelomalacia).

Aged↗
PubMed1998

Alterations of bone turnover and bone mass at different skeletal sites due to pure glucocorticoid excess: study in eumenorrheic patients with Cushing's syndrome.

The aim of the present investigation was to study the effect of glucocorticoid excess on bone mass and turnover not influenced by other diseases known to affect skeleton and/or by different gonadal status and sex. We studied several markers of bone turnover and bone mineral density (BMD) by both quantitative computed tomography (at spine and forearm) and dual x-ray absorptiometry (at spine and three femoral sites) in 18 eugonadal female patients affected by Cushing's syndrome (CS) compared to 24 eugonadal healthy female subjects matched for age and body mass index. In CS patients, serum bone Gla protein, a marker of osteoblastic function, was reduced (3.28 +/- 2.3 vs. 6.47 +/- 2.5; P < 0.01), and bone resorption was increased, as indicated by increased urinary hydroxyproline (36.6 +/- 12 vs. 29.0 +/- 9.1, P < 0.05) and urinary deoxypyridinoline (22.1 +/- 8.0 vs. 16.4 +/- 6.3; P < 0.05). BMD was significantly (P < 0.05 or P < 0.01) reduced at all sites, except cortical forearm, in CS patients compared to controls. By comparing z-scores of reduced BMD in CS patients, spinal trabecular BMD was found to be the most severely affected. Furthermore, disease activity, as measured by urinary free cortisol, was significantly correlated with bone Gla protein (r = -0.57; P < 0.02), urinary hydroxyproline (r = 0.57; P < 0.02), urinary deoxypyridinoline (r = 0.48, P < 0.05), and BMD measured at spine and femur. Our results show that compared to matched control subjects, female eumenorrheic CS patients have reduced osteoblastic function, increased bone resorption, and reduced BMD, and that the severity of these abnormalities is statistically related to the severity of disease activity, as indicated by urinary free cortisol. Moreover, our data suggest a site and tissue specificity of the effect of glucocorticoid excess on bone mass.

Absorptiometry, Photon↗
PubMed1998

Use of the GDC crescent for embolization of tumors fed by cavernous and petrous branches of the internal carotid artery. Technical note.

This report presents two cases of hypervascular tumor in which the cavernous and petrous internal carotid artery feeding vessels were successfully occluded using a new endovascular device, the crescent-shaped platinum Guglielmi detachable coil (GDC). With this new embolic agent the risk of unwanted embolization of normal intracranial arteries was significantly reduced. The GDC "crescent" seems particularly useful when distal, superselective, and controllable occlusion of small arterial feeding vessels is the goal of the treatment.

Adult↗
PubMed1998

Unruptured aneurysms presenting with mass effect symptoms: response to endosaccular treatment with Guglielmi detachable coils. Part I. Symptoms of cranial nerve dysfunction.

OBJECT: Embolization of intracranial aneurysms by using Guglielmi detachable coils (GDCs) is proving to be a safe method of protecting aneurysms from rupture. Occasionally, patients with unruptured intracranial aneurysms present with symptoms related to the aneurysm's mass effect on either the brain parenchyma or cranial nerves. In the present study, the authors conducted a retrospective review to evaluate the response to GDC embolization in a series of 19 patients presenting with cranial nerve dysfunction due to mass effect. METHODS: Aneurysms were classified by size, shape, wall calcification, and amount of intraluminal thrombus. Patients were classified by duration of symptoms prior to GDC treatment (range < 1 month to > 10 years). Clinical assessment was performed within days of the GDC procedure and at later follow-up appointments (range 1-70 months, mean 24 months). In the immediate post-GDC period, four patients experienced worsening of cranial nerve deficits. Two of the four patients had transient worsening of visual acuity, which later improved to better than baseline status. Another patient who had presented with headache and seventh and eighth cranial nerve deficits from a vertebrobasilar junction aneurysm had improvement in these symptoms, but developed a new diplopia. The fourth patient had worsening of her visual acuity, which had not resolved at the 1-month follow-up examination; this patient later underwent surgical decompression. CONCLUSIONS: On late follow-up review, the response was classified as complete resolution of symptoms in six patients (32%), improvement in eight patients (42%), no significant change in four patients (21%), and symptom worsening in one patient (5%). Patients with smaller aneurysms and those with shorter pretreatment duration of symptoms were more likely to experience an improvement in their symptoms following GDC treatment, although statistical significance was not reached in this series (p=0.603 and p=0.111, respectively). The presence of aneurysmal wall calcification (six patients) or intraluminal thrombus (12 patients) showed no correlation with the response of mass effect symptoms in these patients.

Adult↗