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J M Bigot

Publications and source records attributed to J M Bigot.

At least 55 records · Page 3Linked to original sources
PubMed1994

Magnetic resonance imaging findings in pulmonary Kaposi's sarcoma: a series of 10 cases.

Since chest X-ray and CT scan features of Kaposi's sarcoma (KS) are nonspecific, we wanted to test the hypothesis that the histological components of this tumour and/or the associated haemorrhagic component, may result in a characteristic signal pattern on magnetic resonance imaging (MRI). Thoracic MRI was performed in a prospective manner in ten patients with acquired immune deficiency syndrome (AIDS) and pulmonary KS. MRI examinations (1.5 Tesla) included Spin-echo T1 (SE-T1), before and after gadolinium injection, as well as T2-weighted sequences (SE-T2). For each sequence the signal intensity of lesions was measured and compared with each other as well as with the signal intensity of muscle. Results were compared to the hemosiderin content of macrophages in the bronchoalveolar lavage (BAL) in all patients and with histological findings in three. The results were compared to values obtained in a control group of seven patients with pneumocystis carinii pneumonia. SE-T1 showed focally increased signal intensity in the pulmonary parenchyma (n = 5). Signal enhancement in parenchymal lesions (n = 10) and along peribronchovascular trees (n = 5) was observed after gadolinium injection. The second echo of SE-T2 showed a markedly reduced signal intensity in pathologic areas (n = 10). This last finding was not observed in the control group. In conclusion, we have identified a pattern of MRI signal abnormalities suggestive of Kaposi's sarcoma. The MRI signal intensity of KS lesions may be related to the angiomatous and fibrous components of the tumour.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Opportunistic Infections↗
PubMed1994

[Contribution of imaging in the diagnosis and follow-up of thoracic tuberculosis].

Imaging as an essential tool for diagnosis and follow-up of pulmonary tuberculosis. Standard radiography is of prime importance, while in a large number of cases computed tomography (CT) and in selected exceptional cases with spinal involvement, magnetic resonance imaging (MRI) offer further precisions. CT is particularly important for diagnosis because of a better spatial visualization of the lesions and a better evaluation of their structure, both in the parenchyma and in the mediastinum; this indication is especially important in black Africans and in AIDS patients. CT can also be used to guide biopsies. It is particularly important for prognosis in the acute phase even though the tuberculosis may be patent and the bacterial strain identified. There is however still room for discussion on the balance between requirements, usefulness and cost. Finally CT is an excellent means of conducting long-term follow-up of sequellae as long as it is performed at least one year after the initial manifestations of the disease.

AIDS-Related Opportunistic Infections↗
PubMed1994

Magnetic resonance imaging in adults presenting with severe acute infectious cellulitis.

BACKGROUND AND DESIGN: Early categorization of some acute soft-tissue infections, such as severe infectious cellulitis (IC) without or with secondary abscess formation, necrotizing fasciitis (NF) or pyomyositis, is frequently difficult. The first one requires only medical treatment, the remaining ones require either surgery or closed drainage. To determine the presence and the extent of these infections early, we have prospectively studied the value of magnetic resonance imaging in patients admitted for IC with local or general criteria of severity. Images were analyzed on a blind basis. Definite diagnosis was obtained by reviewing clinical records and, in most patients, the results of an invasive procedure. RESULTS: Twenty-six patients (56 +/- 23 years old) were included in this study. Among them, 13 received gadolinium-diethylene-triaminepenta-acetic acid intravenously. The final diagnosis was pyomyositis (five patients), NF (three patients), or IC with (seven patients) or without (11 patients) subcutaneous abscess. Images specific for these diseases were best outlined with T2-weighted sequences. In patients with pyomyositis or subcutaneous abscess(es), we observed spindle-shaped or round, well-defined areas of high signal intensity within the muscles or subcutis, respectively. Patients with NF exhibited numerous homogeneous, well-defined dome-shaped areas of hypersignal in the deep hypodermis. In patients with uncomplicated IC, these dome-shaped areas of hypersignal appeared ill-defined, heterogeneous, smaller, thinner, and less numerous than those in patients with NF. CONCLUSIONS: In patients presenting severe IC, magnetic resonance imaging provided an early clue in the diagnosis of pyomyositis, NF, and abscess-complicated IC. By precisely defining the extent of these infections, it helped to plan surgical treatment.

Abscess↗
PubMed1994

[Imaging of thoracic tuberculosis].

This paper reviews the various radiological signs of tuberculosis including cavities and nodules, alveolar foci, hilar or mediastinal lymphadenopathy and serosal, bronchial and vertebral involvement. It describes the various clinical features and the clinical course of tuberculosis depending on the presence or absence of these signs and their combinations and according to the particular clinical context.

AIDS-Related Opportunistic Infections↗
PubMed1993

Sonography in AIDS-related cholangitis: prevalence and cause of an echogenic nodule in the distal end of the common bile duct.

OBJECTIVE: The purpose of this study was to determine the prevalence and cause of an echogenic nodule in the distal end of the common bile duct seen on sonograms in patients who have AIDS-related cholangitis. SUBJECTS AND METHODS: Sonograms of the liver and bile ducts were obtained in 15 patients who had AIDS-related cholangitis. Both 3.75- and 5-MHz transducers were used in all patients. The appearance of an echogenic nodule in the distal end of the common bile duct was compared with the results of endoscopic retrograde cholangiograms in 12 patients and with biopsies of the papilla of Vater in the first five cases. RESULTS: Sonograms showed a hyperechoic nodule in the distal end of the common bile duct in 10 of the 15 cases. Visualization was improved after oral administration of water. The finding correlated with edema of the papilla of Vater noted on retrograde cholangiograms in eight cases. Biopsy of the papilla of Vater in five cases showed an inflammatory infiltrate. The nodule became smaller in one patient when cholestasis improved after treatment for cryptosporidiosis. CONCLUSION: An echogenic nodule was detected in the distal end of the common bile duct on sonograms in two thirds of patients who had AIDS-related cholangitis. Our findings suggest the abnormality is caused by edema of the papilla of Vater.

Acquired Immunodeficiency Syndrome↗
PubMed1993

[Digestive carcinoid tumors].

Three examples of intestinal carcinoid tumours are reported. As the sign in conventional radiology are non-specific and inconstant, the computed radiographic signs are stressed. Small bowel examination showed both direct signs, intraluminal filling defects, and indirect signs with separated bowel loops, sometimes angulated and fixed. In one unusual case, all the jejunal loops were affected. On CT the specific finding was a retractile mesenteric infiltration.

Aged↗
PubMed1993

[Congestive cardiac failure secondary to hepatico-portal arteriovenous fistula. Apropos of a case and review of the literature].

A 66 year old man with mild hypertension developed congestive cardiac failure of rapid onset associated with a continuous epigastric murmur suggesting an arteriovenous fistula. Doppler ultrasonography, computed tomography, magnetic resonance imaging and abdominal arteriography showed the fistula to arise from a large thrombosed aneurysm of the hepatic artery which had ruptured into the portal vein. Echocardiography and radionuclide angiography showed normal left ventricular systolic function. The patient underwent aneurysmorrhaphy and suture of the portal vein without any complications and the murmur and signs of cardiac failure disappeared. Histological examination showed the arterial lesion to be due to atherosclerosis. The authors underline the rarity of aneurysms of the hepatic artery and, above all, of their rupture into the portal system as there have only been 7 previously reported cases. Fistulae of the portal system are usually well tolerated, the commonest complication being portal hypertension. Cardiac failure is an exceptionally rare occurrence: it may be observed when the fistula develops suddenly and has a high flow rate, and in patients with abnormal myocardial function.

Aged↗
PubMed1993

[Sarcoma of the spine in Paget's disease of bone. Apropos of 8 cases].

Eight cases of spinal sarcoma complicating Paget's disease seen in different centers were reviewed. Clinical and radiological features of this condition were determined on the basis of these 8 cases and of 51 previously published cases. In the current series as well as in previous reports, most cases involved the lumbar and sacral spine and manifested as low back pain with sciatica and early development of neurological deficits. Roentgenographic diagnosis proved difficult because of the anatomic complexity of the spine and architectural changes characteristic of the pagetic bone. The most common radiological features was a mixed pattern with both sclerosis and central osteolysis. Computed tomography performed in one patient of current series disclosed osteolysis of the sacrum (not visible on plain roentgenograms) with tumor spread to adjacent soft tissues. Features shared by spinal and nonspinal sarcomas complicating Paget's disease include advanced mean age of patients, predominance of osteogenic sarcomas among histologic forms, increased risk of sarcoma in polyostotic Paget's disease, and a very grim prognosis. Development of a neurological deficit in a patient with Paget's disease is an unusual occurrence which should suggest sarcomatous transformation. Roentgenographic changes are difficult to identify on plain films of the spine and consequently CT scan studies are warranted whenever a sarcoma is suspected.

Aged↗
PubMed1993

[Digestive carcinoid tumors].

Three examples of intestinal carcinoid tumours are reported. As the signs in conventional radiology are non-specific and inconstant, the computed radiographic signs are stressed. Small bowel examination showed both direct signs, with intraluminal filling defects, and indirect signs with separated bowel loops, sometimes angulated and fixed. In one unusual case, all the jejunal loops were affected. On CT the specific finding was a retractile mesenteric infiltration.

Carcinoid Tumor↗
PubMed1993

[Magnetic resonance imaging in the exploration of abdominal and anoperineal fistulas in Crohn's disease].

In a twelve month period, ten patients with fistulas related to Crohn's disease were explored by magnetic resonance imaging performed with a high-field supraconductive magnet. This technique demonstrated 3 cases of peri-anal abcesse invisible by other imaging modalities, and in 8 cases, fistules tracts, including 5 complex fistules, and one communicating with the bladder. This examination defined the extension of these lesions relative to the elevator plane, and demonstrated diffusion to the inferior space in 4 cases, to the superior space in 2 cases, and to both spaces in 2 cases. This method seems to be efficacious and does not expose the patient to X-rays.

Adult↗
PubMed1993

[Thoracic x-ray computed tomography and unexpected diagnosis of pulmonary embolism].

The gold standard for the diagnosis of pulmonary embolism is still pulmonary angiography. Chest CT scan with injection of contrast medium can demonstrate a pulmonary embolism. In some cases, CT may discover a non suspected embolism. The aim of this retrospective study was to point out when an injection of contrast medium is necessary during CT scan of the chest to avoid to overlook and unsuspected pulmonary embolism. Ten cases of suspected pulmonary embolism on CT were retrospectively studied. Two cases were false positives. Our method did not allow to study false negatives. Out of the eight true positive cases, four were not suspected by the physician and in all cases, the exam record was not really clear. At the end of this study and referring to the literature, we conclude that CT scan of the chest can be performed with injection of contrast medium if a pulmonary embolism is one of the eventual diagnosis when an other suspected affection is an indication for CT.

Aged↗
PubMed1991

[Intradural metastases of visceral cancers. MRI aspects. Apropos of 2 cases].

The authors report two cases of intradural metastasis: a man with bronchopulmonary cancer suffering from left L5 sciatic pain and a woman with breast cancer whose examination shows motor weakness of both legs. CT was negative in the first case. Gadolinium injection on T1 sequence shows in the first case small nodular lesions along the roots of cauda equina and in the second case linear enhancements around the spine, at different levels. These aspects are the most frequently reported. MRI is an innocuous and the most sensitive technic for such lesions. An early diagnosis improves the functional prognosis. Despite of radiotherapy and chemotherapy, vital prognosis remains bad because of widespread of the intradural lesions and their frequent association with cerebral metastasis.

Adenocarcinoma↗
PubMed1990

Comparison of magnetic resonance imaging and computed tomography in the preoperative staging of rectal cancer.

Nineteen patients with middle and lower rectal carcinomas were operated on, with abdominoperineal resection in 10 patients, lower anterior resection with coloanal anastomosis in 6 patients, and colorectal anastomosis in 3 patients. The distance of the lower margin of the tumor to insertion of the levator ani on the rectal wall was correctly evaluated by computed tomography in 12 (63%) of 19 patients and by magnetic resonance imaging in 13 (68%) of 19 patients, while digital examination correctly assessed the distance in 15 (79%) of 19 patients. Computed tomography and magnetic resonance imaging were unable to assess extension through the rectal wall. No significant difference was observed between computed tomography and magnetic resonance imaging in assessing extension to the perivesical fat, adjacent organs, pelvic side wall, or lymph nodes. According to the TNM classification, magnetic resonance imaging correctly staged 74% (14/19) of carcinomas, while computed tomography correctly staged 68% (13/19).

Aged↗