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R Dore

Publications and source records attributed to R Dore.

At least 19 recordsLinked to original sources
PubMed2006

Percutaneous computed tomography-guided radiofrequency thermal ablation of small unresectable lung tumours.

The aim of the current study was to evaluate the safety and the efficacy of radiofrequency thermal ablation (RFTA) for the treatment of nonsmall cell lung cancer (NSCLC) and isolated pulmonary metastases (METs) from colorectal cancer (CRC). A total of 31 patients (15 with NSCLCs and 16 with CRC lung METs), with 36 lung tumour nodules (mean+/-sd diameter: 22+/-8 mm, range: 10-35 mm) underwent computed tomography (CT)-guided RFTA using expandable electrodes. Contrast-enhanced CT was performed before and after (immediately and 30+/-5 days) each RFTA session to assess immediate results and complications and repeated 3 and 6 months post-RFTA, as well as every 6 months thereafter, to evaluate long-term results. Complete radiological necrosis was defined as a nonenhancing area at the tumour site that was equal to or larger than the treated tumour; persistence of enhancement at the tumour site indicated incomplete treatment. Local recurrence was defined as an increase in tumour size and/or enhancing tissue at the tumour site. Complete radiological necrosis of the 36 tumours was achieved with 39 RFTA sessions and 42 electrode insertions. No major complications or deaths were observed. Six patients experienced mild-to-moderate pain during the procedure. There were five cases of pneumothorax, none requiring drainage and four cases of pneumonia, which were successfully treated with antibiotics. After a mean follow-up of 11.4+/-7.7 months (range of 3-36 months), the overall local recurrence rate was 13.9% (20 and 9.5% for NSCLC and CRC-METs patients, respectively). Nineteen of the 31 (61.3%) patients were alive (15 apparently disease free) and 12 (38.7%) had died (three from causes unrelated to their cancer). Radiofrequency thermal ablation seems to be a safe, effective method for producing complete ablation of small nonsmall cell lung cancers and pulmonary colorectal cancer metastases.

Aged↗
PubMed2001

Image-aided estimate of tumor burden in Hodgkin's disease: evidence of its primary prognostic importance.

PURPOSE: To explore a more direct method for evaluating tumor burden (TB) in Hodgkin's disease (HD) and to verify its prognostic importance. PATIENTS AND METHODS: The volume of TB at diagnosis was directly and retrospectively measured in 121 HD patients through images of the lesions recorded by computed tomographic (CT) scan of the thorax, abdomen, and pelvis for all deep sites of involvement and many superficial ones, and by ultrasonography (US) for the remaining superficial lesions. RESULTS: The TB, which was obtained from the sum of the volumes of all the lesions measured on CT scans and US and normalized to body-surface area (relative TB [rTB]), showed a median value of 102.6 cm(3)/m(2) (range, 2.2 to 582.8). At multivariate analysis for prognostic value, rTB was the parameter that statistically correlated best with time to treatment failure (P = 2.2 x 10(-6)), followed by erythrocyte sedimentation rate (ESR) (P =.0003), and serum fibrinogen (P =.0112). The prognostic discrimination allowed by rTB alone proved to be clearly superior to that obtained with the score of the International Prognostic Factor Project. The rTB was found to be correlated with many clinical staging parameters (bulky disease, number of involved lymph node regions, serum lactate dehydrogenase, ESR, hemoglobin, Karnofsky index), but its predictability from these variables was low (R(2) =.668). CONCLUSION: Relative TB is emerging as a strong prognostic factor in HD, more powerful than and largely independent of those hitherto known and used. Further studies are needed to confirm these results and exploit their clinical value, particularly the relationship among rTB, drug doses, and response.

Adolescent↗
PubMed2000

Mechanisms for isolated volume response to a bronchodilator in patients with COPD.

We hypothesized that an altered effect of lung inflation on airway caliber may in part explain the isolated volume response to bronchodilators, i.e., an increase of forced vital capacity (FVC) without change in 1-s forced expiratory volume (FEV(1)). Small-airway caliber was measured by high-resolution computed tomography at functional residual capacity and total lung capacity in five chronic obstructive pulmonary disease patients with an isolated increase of FVC (FVC responders) and five with an increase of both FVC and FEV(1) (FVC-FEV(1) responders) after inhalation of salbutamol. In FVC-FEV(1) responders, the airway diameter increased with the cube root of increase in lung volume but was unchanged or even decreased in four of five FVC responders. FVC responders had more severe emphysema, as inferred from lung function and imaging studies, than FVC-FEV(1) responders. We speculate that longitudinal traction or space competition (Verbeken EK, Cauberghs M, and Van de Woestijne KP, J Appl Physiol 81: 2468-2480, 1996) are possible underlying mechanisms. We conclude that the isolated volume response to bronchodilators is associated with severe emphysema and likely results from an altered effect of lung inflation on airway caliber.

Administration, Inhalation↗
PubMed2000

Eosinophilic pleural effusion due to mesalamine. Report of a rare occurrence.

Mesalamine-induced lung toxicity has often been described. We report on a case of a patient who underwent mesalamine treatment, though in the absence of established criteria required for diagnosing Crohn's disease (CD) or ulcerative colitis (UC). He developed an adverse respiratory reaction to the drug, thus definitely proving its lung damaging capacity. The clinical presentation included eosinophilic pleural effusion, a feature never previously described in association with mesalamine intake.

Adult↗
PubMed1999

The role of computed tomography in the preoperative assessment and follow-up of oromandibular reconstruction with microvascular osteomyocutaneous free flaps.

OBJECTIVE: To investigate the capacity of helical CT in the pre- and post-operative management of oromandibular reconstruction of patients with oropharyngeal carcinoma using microvascular composite free flaps. MATERIALS/METHODS: Thirty-four patients with oropharyngeal cancer were examined by helical CT and nine (six men and three women) submitted to oromandibular reconstruction. The osteomyocutaneous flaps used for reconstruction were taken from the iliac crest in six cases and from the fibula in three cases. All patients were examined by CT 1 - 4 days postoperatively and then at 6 monthly intervals. Double helical scans were performed in all cases, with slices of 2 - 3 mm for primary lesion studies and 5 mm for lymph node staging, pitch >/=1 and RI=1. Multiplanar (MPR) and 3D reconstructions were obtained from pre- and postoperative CT examinations. RESULTS: Preoperative CT showed massive bone infiltration in six of the nine surgical patients and marginal infiltration in three. These findings were confirmed histologically. There were no false negatives. The immediate postoperative examination showed correct flap positioning in eight of nine cases. The flap underwent ischemic necrosis in two cases; CT showed very early signs of bone ischemia in both. CT detected two cases of recurrence after about 1 year. CONCLUSIONS: Axial CT permitted adequate assessment of the extent of mandibular infiltration and detected early ischemic complications and distant recurrences. Integration with MPR and 3D reconstructions simplified the choice of flap type and size and enabled the postoperative assessment of correct flap positioning. This helped the surgeon plan subsequent rehabilitation with osseo-integrated implants.

Aged↗
PubMed1999

Pulmonary atelectasis during paediatric anaesthesia: CT scan evaluation and effect of positive endexpiratory pressure (PEEP).

The case series consisted of ten children, ranged in age from one to three years (median 1.8 yrs), and in body weight from 10.2 to 13.5 kg (median 11.7 kg), in ASA class 1 or 2, all without lung disease. Having undergone general anaesthesia for cranial or abdominal CT scans, the patients were studied for pulmonary morphology. The first pulmonary CT scan was taken five min after induction of general inhalational anaesthesia; preoxygenation was avoided and an intraoperative FiO2</=0.4 was used. Densities in dependent regions of both lungs were observed in all children. After ventilation with PEEP of 5 cmH2O, all the observed densities disappeared without impairment of heart rate, blood pressure, haemoglobin saturation and endtidal CO2 (PECO2). We conclude that the appearance in children of atelectasis cannot be explained by a reabsorption of O2 mechanism and by denitrogenation. However, a PEEP of 5 cmH2O is able both to recruit all the available alveolar units, and to induce the disappearance of atelectasis in dependent lung regions.

Anesthesia, Inhalation↗
PubMed1998

Spiral CT angiography and surgical correlations in the evaluation of intracranial aneurysms.

We investigated the accuracy of spiral computed tomography angiography (CTA) in the detection and study of intracranial aneurysms by comparing CTA with selective angiograms and surgical findings. Twenty-six patients (9 men and 17 women; mean age 53.1 +/- 1.8 years) with suspected intracranial aneurysms were submitted to CTA (1- to 2-mm slices, pitch 1:1, 24 s, RI = 1) after a conventional CT examination showing subarachnoid hemorrhage (SAH) in 19 cases and during neuroradiological investigations performed for other reasons in 7 cases. One hundred twenty to 150 ml iodate contrast agent (0.3-0.4 gI/ml) were injected intravenously at 5 ml/s rate and with 12- to 25-s delay calculated with a preliminary test bolus. Three-dimensional shaded surface display (3D SSD) and maximum intensity projection (MIP) reconstructions were obtained from axial images. Then, within 48 h, all patients were submitted to digital subtraction angiography (DSA), with separate assessment of CTA and DSA findings. Twenty-two aneurysms shown by CTA were confirmed at DSA and surgery (true positives), whereas the vascular lesion was not confirmed at DSA in 2 cases (false positives). The presence of intracranial aneurysms was excluded at both CTA and subsequent DSA in 7 cases (true negatives) and there were no false negatives; sensitivity was 100 %, specificity 77.8 %, and diagnostic accuracy 93.5 %. Computed tomography angiography aneurysm location was confirmed at surgery in all cases, with very high accuracy in assessing the presence of an aneurysm neck (100 %). Computed tomography angiography accurately depicted the aneurysm shape in 20 of 22 cases, but failed to depict its multilobed nature in 2 cases. The mean aneurysm diameter calculated at CTA was 0.99 +/- 0.12 cm vs 1.09 +/- 0.11 cm at surgery (p < 0.01). The present results suggest that the high sensitivity of CTA, if confirmed by further studies, might help in avoiding having to resort to arteriography after negative CTA in SAH patients.

Adult↗
PubMed1998

[Complex maxillofacial trauma: diagnostic contribution of multiplanar and tridimensional spiral CT imaging].

INTRODUCTION: Adequate radiologic assessment of the maxillofacial trauma patient is the basis for planning reparative surgery. We investigated the yield of the integration of axial CT with multiplanar (MP) and three-dimensional (3D) reconstructions with the Spiral technique. MATERIAL AND METHODS: Thirty-five patients (21 men and 14 women, mean age: 31.2 years) with complex maxillofacial traumas were submitted to Spiral CT. Images were acquired with 2-3-mm collimation, 1:1 to 2:1 pitch, 210 mAs, 120 kV, 15-24 s Spiral scan, RI = 1. 3D reconstructions were always obtained and used to guide MPRs targeted on the single injury. The examinations were retrospectively given a score, namely 1 if 3D and MPR yielded no more important diagnostic information than axial CT, 2 if 3D and MPR permitted better detailing of some axial CT findings and thus improved image reading, and 3 if 3D and MPR showed new injuries missed on axial images. Then, a radiologist and a maxillofacial surgeon reviewed the 3D images together only to assess in which cases they were useful to optimize surgical planning. RESULTS: Nine cases (25.7%) scored 1, seventeen (48.6%) scored 2 and nine (25.7%) scored 3. MP and 3D reconstructions were useful or determinant (2 + 3) in over 74% of cases. 3D images made surgical planning easier in 15 of 32 surgical patients (46.8%), allowing the surgeon a better panoramic view of the complex fracture. CONCLUSIONS: The greatest advantage of multiplanar imaging is the improved depiction of skeletal injuries along a horizontal plane, paralleling that of axial scans. The depiction of fractures of cribrum and of orbital roof and floor was particularly useful from a clinical viewpoint. MPRs clearly depicted herniation and incarceration of the lower rectus muscle in blow-out fractures. MP and 3D reconstructions better defined the presence and grade of displaced bone fragments in nearly vertical structures, such as the upward branches and coronoid apophysis of the mandible. 3D images alone never showed any more fractures than those seen on axial and MP images. 3D images are especially useful to the surgeon because they permit the panoramic depiction of the fracture complex, which facilitates treatment planning. The radiologist can use 3D reconstructions to guide the acquisition of targeted MP reconstructions, for better diagnostic yield. The Spiral technique, with its pitch increases up to 2, permits to limit the radiation dose while preserving the quality of postprocessing reconstructions. Finally, decreasing the execution time is important in multiple trauma patients who are often clinically unstable or have damaged vital organs.

Adult↗
PubMed1997

Spiral CT findings in a case of pulmonary sequestration.

Pulmonary sequestration has always been diagnosed by direct demonstration of the vessels tributary to the lesion, usually by angiography. Conventional CT can identify the arterial supply in only two thirds of cases. We report a case of pulmonary sequestration diagnosed using Spiral CT, based on the demonstration of both arterial supply and venous drainage. The capabilities of Spiral CT to detect subtle vessel abnormalities and to yield reliable multiplanar imaging enabled us to show the whole course of both the artery and the vein tributary to the lesion. Axial images were the most useful ones to diagnose pulmonary sequestration; 2D and 3D reconstructions were useful for a detailed and immediate spatial depiction of the parenchymal abnormality and of its vascular pedicle.

Bronchopulmonary Sequestration↗
PubMed1997

Communicating bicornuate uterus with double cervix and septate vagina: an uncommon malformation diagnosed with MR imaging.

We report a case of communicating uterus diagnosed with MRI. These uterine malformations are characterized by a communicating tract between two separate uterocervical cavities, which is usually detected with hysterosalpingography performed for a suspected uterine malformation. In our patient MRI was performed after the clinical finding of a double cervix and a vaginal septum and demonstrated two separate uterine cavities, each of them with its own junctional area, and an isthmian transverse communicating tract with endometrial tissue inside, which helped make the diagnosis of a type-4 a communicating uterus according to Toaff.

Adult↗
PubMed1997

The use of spiral computed tomography in the localization of impacted maxillary canines.

PURPOSE: To compare spiral CT with conventional radiography in planning the orthodontic treatment of impacted permanent maxillary canines. METHODS: Nineteen patients with 29 malpositioned permanent maxillary canines (15 palatal and 12 buccal impactions, one ectopic and one transposition) were examined with conventional panoramic and lateral cephalometric radiography and with spiral CT (at 1 mm slice thickness, and 1:1 or 2:1 pitch) using multiplanar (MPR) and 3D reconstruction. RESULTS: Conventional radiography failed to depict root resorption especially on the buccal surfaces of the incisor teeth. CT located impacted teeth better. Contact between impacted maxillary canines and incisor roots was demonstrated in 26 cases and root resorption in eight. MPR proved to be superior for the orientation of impacted teeth, and, in two cases, confirmed the presence of minimal root lesions for which axial images had proved inconclusive. The 3D reconstructions were useful in targeting the MPR. CONCLUSIONS: CT facilitates the treatment of impacted canine especially when the teeth are very oblique to the arch. Root resorption is better demonstrated especially on the palatal and buccal surfaces of the adjacent incisors. Spiral CT reduces examination time and risk of accidental movement, thus optimizing MPR quality. Examination at 2:1 pitch enables a significant reduction in radiation exposure without loss of image quality.

Adolescent↗
PubMed1997

Use of spiral computed tomography for multiplanar dental reconstruction.

OBJECTIVE: To compare spiral with conventional CT for multiplanar reconstruction (MPR) prior to dental implant placement. METHODS: Ten patients underwent conventional and then Spiral CT at 1 mm slice thickness. In six patients (Group A) the pitch was 1:1; the other four (Group B) it was 2:1. Image quality and clinical features were evaluated separately on axial and reconstructed images by two experienced radiologists who scored each parameter from 1 (poor, non-diagnostic) to 3 (good, diagnostic). RESULTS: Loss of spatial resolution with spiral CT was not significant and the diagnostic yield poorer only for trabecular bone structure. The MPRs were better and depiction of the mandibular canal more reliable. CONCLUSIONS: We recommend the use of spiral CT instead of conventional CT for dental MPR because examination time is shorter and patient comfort is improved. Use of a pitch of 2:1 permits a marked reduction in X-ray dose with no loss of image quality.

Aged↗
PubMed1996

The role of functional respiratory tests in predicting pneumothorax during lung needle biopsy.

In 243 of 945 patients having lung percutaneous needle biopsy, we retrospectively evaluated 10 independent variables that potentially influence the incidence of pneumothorax (PNX): age, sex, lesion size, number of needle passes, needle intrapulmonary route, distance of the lesion from the chest wall, FEV1, FVC, residual volume, and total lung capacity percent predicted. The subjects considered (mean age, 61 years; 192 men and 51 women) performed respiratory function tests within 1 year of the procedure. The sample was also subdivided into four functional groups: restricted patients, obstructed ones, obstructed with alveolar hyperinflation patients, and normal subjects. The variables significantly correlated to PNX were the length of the needle intraparenchymal route (p<0.05) and the distance of the lesion from chest wall greater than 0 cm (p<0.01). None of the functional parameters was determinant in predicting PNX occurrence. Bronchial obstruction was not significantly associated with a higher risk of PNX. Nevertheless, when alveolar hyperinflation was associated with bronchial obstruction, the risk increased significantly (odds ratio, 2.38).

Aged↗