Search PubMed⌕ Search

Biomedical subjects

J Frija

Publications and source records attributed to J Frija.

At least 37 records · Page 2Linked to original sources
PubMed1999

Prognostic value of vertebral lesions detected by magnetic resonance imaging in patients with stage I multiple myeloma.

We assessed the role of spinal magnetic resonance imaging (MRI) and bone densitometry as prognostic factors in patients with asymptomatic stage I multiple myeloma (MM) and negative skeletal survey. 55 consecutive patients underwent spinal MRI and 41 of them underwent bone densitometry by dual-energy X-ray absorptiometry (DEXA). Spinal MRI studies showed evidence of bone marrow involvement in 17/55 patients (31%). A diffuse pattern was present in three patients and a focal pattern in 14 patients, nine of them with only one nodular lesion. During a median follow-up of 25 months, 10 patients had disease progression, 8/17 patients with abnormal MRI and 2/38 patients with normal MRI. Median time to disease progression was not reached in both groups but was significantly different for patients with normal and those with abnormal patterns on MRI (P < 0.0001). Lumbar BMD was only slightly decreased compared with normal people (median lumbar Z score -0.43) and was not of prognostic value. Using a multivariate analysis the only two independent significant prognostic parameters were abnormal MRI (P<0.001, HR 30.4, 95% CI 4.3-213) and bone marrow plasmacytosis >20% (P=0.004, HR 16.4, 95% Cl 2.6-104). Thus, spinal MRI but not bone densitometry, appeared to be justified in patients with stage I asymptomatic MM and negative skeletal survey.

Absorptiometry, Photon↗
PubMed1999

[Scanner-guided biopsy technic with abdominal compression].

The aim of this study was to present a CT-guided biopsy technique using an abdominal compression device. With this system, the digestive structures (mainly the colon and the small bowel) can be displaced away from the needle track and the distance between the skin and the target lesion can be reduced by approximately one-third. The technique has been used in 29 patients and was successful in 28, allowing node biopsies in the mesenteric, retroperitoneal or pelvic areas. The compression system is easily mounted and used standard sterilizable material. The procedure is well tolerated by patients and complication rate is not raised compared with conventional biopsy techniques.

Abdomen↗
PubMed1999

[Fast imaging sequences].

Although conventional spin echo and gradient echo sequences are still in general use, the need to improve the temporal resolution of MRI and to study organ function has prompted to develop fast imaging techniques. These techniques are based on different approaches, but present common underlying principles which allow optimize k space fitting. As a result, both contrast and spatial resolution may be improved aside from the capability to reduce scan time. The selection of the most appropriate fast imaging technique will depend on the needed temporal resolution, spatial resolution and contrast. The aim of this paper is to review and explain the basic principles of fast imaging techniques, with emphasis on their advantages, limitations, and clinical applications.

Computer Systems↗
PubMed1998

Computed radiography.

In several medical centers computed radiography has almost completely replaced the use of conventional screen-film systems for general radiography. The aim of this paper is to explain the basic principles of the four most frequently numerical detectors used in the world, with emphasis on the phosphor plates, which are the most frequently used both in hospitals and by practitioners. The other two systems are based on a receptor with selenium. The fourth uses charged coupled device (CCD) detectors. The most important principles of digital processing are then described with concentration on unsharp mask filtering. In the future computed radiography will replace standard radiology and will create a system in medicine using the power of computers to archive--with more efficiency and less space--patient medical data. The transmission of data to workstations and the processing of this data is the topic of a new field in medicine.

Humans↗
PubMed1998

Fat suppression techniques in MRI: an update.

Due to short relaxation times, fat has a high signal on magnetic resonance images (MRI). This high signal, easily recognized on MRI, may be useful to characterize a lesion. However, small amounts of lipids are more difficult to detect on conventional MRI. In addition, the high signal due to fat may be responsible for artifacts such as ghosting and chemical shift. Lastly, a contrast enhancing tumor may be hidden by the surrounding fat. These problems have prompted development of fat suppression techniques in MRI. Fat may be suppressed on the basis of its difference in resonance frequency with water by means of frequency selective pulses or phase contrast techniques, or on the basis of its short T1 relaxation time by means of inversion recovery sequences. Lastly, hybrid techniques combining several of these fat suppression techniques are also possible. The aim of this paper is to review the basic principles of all these fat suppression techniques and to exemplify their clinical use.

Adipose Tissue↗
PubMed1998

Surgical endoscopic techniques in the diagnosis and follow-up of patients with lymphoma.

BACKGROUND: In patients with lymphoma, tissue for histology can be obtained through image-guided techniques or by surgery. The aim of this study was to assess the efficacy of surgical endoscopic techniques in obtaining adequate tissue specimens. METHODS: Ninety-two patients with suspected or confirmed lymphoma were referred for a surgical biopsy of a deeply located intrathoracic or intra-abdominal mass or lymph node. The 86 patients who had surgery using a surgical endoscopic technique were included in this study. There were 54 men and 32 women, of mean age 34 (range 15-78) years. Most were selected directly for surgery while five previously had a failed computed tomography-guided biopsy. A total of 89 procedures were performed in 86 patients: laparoscopy (15 patients), thoracoscopy (61) and mediastinoscopy (13). RESULTS: No patient died. One intraoperative complication occurred during thoracoscopy (1 per cent). Two postoperative complications were noted (2 per cent). Three patients required conversion to open surgery (3 per cent). Adequate tissue for histology was obtained by surgical endoscopic procedures in 87 per cent. Twelve of 13 mediastinoscopies were successful. After thoracoscopy, the success rate was 92 per cent but only nine of 15 laparoscopies were considered successful. CONCLUSION: In patients with lymphoma, surgical endoscopic techniques have a high diagnostic yield and a low morbidity rate. Barring exceptional circumstances these should be favoured rather than conventional open surgery.

Adolescent↗
PubMed1998

[What is bright on T1 MRI scans?].

The list of entities associated with a high signal intensity on T1-weighted images is extensive and classically includes fat, proteins, hemorrhage, melanin and gadolinium. However, additional entities may be responsible for abnormally high signal intensity on T1-weighted images. These include ion deposition in metabolic disorders, free radicals, increased proton density, flow phenomena, some artifacts, and new contrast agents. The aim of this article is to display both the common and uncommon causes for a high T1 signal intensity and to discuss the underlying mechanisms or attributable pathophysiology for this phenomenon.

Artifacts↗
PubMed1997

Radiologic anatomy of the inferior lung margins as demonstrated on computed radiography with enhancement of low frequencies.

The aim of this work was to describe the radiologic anatomy of the inferior lung margins (ILMs). The method was to enhance the low frequencies of 50 normal chest computed radiographs. On each side, the anterior and posterior ILMs were divided into two halves. The frequency of visibility of each half of each ILM was calculated as their shape, lateral and medial continuities, depth, and vertebral level. The differences were compared by a paired Student t-test. The right posterior ILM was always visible and usually concave upward (94%). Its height was 8.7 +/- 1.6 cm. Its most inferior part faced L1 or L2 in 92% of cases. It was continuous medially inside with the azygo-esophageal recess in 96% of cases. The left posterior ILM was not visible laterally in 34% of cases and medially in 60% of cases. It was most often concave upward (82% of cases). Its height was 6.9 +/- 1.5 cm. Its most inferior part was at the level of L1 or L2. It was continuous medially with either the left paraspinal line or the paraaortic line. The right anterior ILM was visible in 76% of cases. It was most often oblique upward and medially (46%) or concave upward (33%) and often notched (38%). The left anterior ILM was visible in 64% of cases and more often oblique inward and upward (58%). It was continuous medially with the left inferior precardiac recess. The anterior ILMs were more variable than the posterior. The posterior ILMs were very similar in shape and inferior level and differed in depth only by the difference of height of the diaphragmatic cupolas.

Adult↗
PubMed1997

Sternal abscess due to Bartonella (Rochalimaea) henselae in a renal transplant patient.

Bartonella henselae, previously called Rochalimaea henselae, is the causative agent of cat scratch disease (CSD) in immunocompetent subjects and bacillary angiomatosis in immunocompromised ones. Bone lesions are common in bacillary angiomatosis, but not in CSD. We present the case of a patient with a renal transplant treated by immunosuppressive therapy who developed a sternal abscess with a histological pattern of CSD. The CT pattern was that of a lytic bone lesion with adjacent fluid collection. The diagnosis was made on the basis of a polymerase chain reaction amplification performed on bone material. Bartonella henselae is a newly described bacteria that causes CSD in a normal host and bacillary angiomatosis in immunocompromised patients. We report a case of an osteolytic lesions of the sternum with adjacent fluid collection related to CSD, which occurred in a patient with a renal transplant.

Abscess↗
PubMed1997

Cerebral tuberculosis in patients with the acquired immunodeficiency syndrome (AIDS). Report of 6 cases and review.

Cerebral tuberculosis (TB) was diagnosed in 6 (4%) of 156 HIV-infected patients with TB seen at our institution over 6 years. We describe here the clinical and radiologic features of these cases and of 15 others reported in the literature. Of the 21 patients, 59% were intravenous drug users. Presenting symptoms were fever (76%), confusion (52%), seizures (38%), and headache (38%). Fourteen patients (66%) had previous or active extracerebral TB at presentation. Cranial CT scan showed ring-(62%) or nodular-(24%) enhancing lesions or mixed forms (14%). Among the 12 patients who underwent a brain biopsy, bacteriologic evidence of TB was found in 9. Four patients (19%) died during hospitalization. Among the 17 others who received antituberculous therapy, only 1 developed neurologic sequelae. Five patients also received steroid therapy to control cerebral edema or paradoxical growth of the cerebral mass lesions. TB should be considered as a cause of cerebral mass lesions in HIV-infected patients, especially if tuberculous infection is suspected at other sites.

Acquired Immunodeficiency Syndrome↗
PubMed1997

[Digital radiography of the thorax].

Digital radiography of the thorax can, now be substituted to conventional chest radiography. Computed radiography with phosphor plates and the new selenium detector are emphasized. The major image processing are explained. Successively the main other methods of digital radiography are described: scanning equalization radiography, laser-digitized radiography and multiwire proportional chambers. Then the advantages and the drawbacks of chest computed radiography are extensively reviewed.

Humans↗
PubMed1997

Dural sinus thrombosis: CT and MR imaging of different stages.

Cerebral dural sinus thrombosis remains an uneasy clinical diagnosis because it may present with a spectrum of nonspecific manifestations. CT and MR findings have been described to help recognize this entity. We report here a case with different stages of thrombosed superior sagittal and right transverse dural sinuses demonstrated by CT and MR imaging.

Adult↗
PubMed1997

[Thoracoscopic approach in pulmonary nodules: a prospective evaluation of a series of 120 patients].

UNLABELLED: More and more pulmonary nodules are currently approached via thoracoscopy. We have evaluated the results and the morbidity of a consecutive series of 120 patients operated on by a single surgeon. PATIENTS AND METHODS: Hundred twenty-two nodules have been approached thoracoscopically in 120 patients. The average size of these nodules was 16 mm (3-30 mm). A pre-operative localisation technique has been used in 61 patients (50%). The procedures were as follows: biopsy (6 cases), wedge-resection (110 cases). A video-assisted lobectomy has been performed in 26 cases. RESULTS: The mortality rate was 0.08% (One case of ARDS in the post-operative course of a video-assisted lobectomy). Intra-operative morbidity rate was 1.6% (2 cases of haemorrhage requiring a thoracotomy and the post-operative morbidity rate was 5%. Six procedures were converted to thoracotomy 55%). The nodules have been localised in all cases but 2 (1.6%). The mean post-operative stay was 4.6 days in the whole series and 3.2 days in the series of patients with a simple biopsy or wedge-resection. COMMENT: The morbidity rate of thoracoscopic resection of lung nodules is very low and decreases with surgeon's experience. Experience allows one not to use a localisation technique in many cases, but the later remains helpful in small size nodules. It allows for a safe, rapid and accurate procedure to be performed. The need for a mini-thoracotomy is very rare. Mastering the techniques of radiological localisation techniques, thoracoscopic biopsy and wedge resection as wall as video-assisted lobectomies should make it possible for thoracoscopic resection of lung nodules to fulfil the criteria of a minimally invasive operation.

Adolescent↗
PubMed1996

Imaging findings in giant pseudotumoral paraesophageal varices.

We report a case of variceal changes of the azygos vein, hemiazygos vein, and paraesophageal collaterals presenting as bilateral posterior mediastinal masses in a patient with long-standing portal hypertension due to hepatosplenic schistosomiasis. The case is unusual because the varices were considerably larger than those usually encountered in portal hypertension. Dynamic CT allowed the diagnosis in demonstrating the vascular nature of these masses, which enhanced to the same degree as the other vessels. Noninvasive techniques, such as color Doppler sonography and MRI, may also be useful due to their multiplanar capabilities.

Azygos Vein↗
PubMed1996

Radiological findings in nine AIDS patients with Rhodococcus equi pneumonia.

Rhodococcus equi (R. equi) infections have been incidentally reported as a cause of pulmonary infection in severely immunocompromised hosts, including AIDS patients. Our purpose is to describe the radiological findings in nine AIDS patients with R. equi pneumonia assessed by bronchoalveolar lavage (BAL), biopsies, cultures of sputum, and hemocultures. All patients were examined by chest radiographs and contrast-medium-enhanced chest CT. Dense pulmonary consolidations with or without cavitations accounted for the most striking radiological patterns. Chest CT also revealed six mediastinal involvements, strongly mimicking a lymphoma. Two of them had multiple bilateral pulmonary nodular opacities. Pleural effusion was not identified. Although intensive therapies were administered, seven among nine patients died within few months. In an AIDS patient living in a rural area or exposed to horses and presenting these radiological patterns, the possibility of R. equi pneumonia should be considered in the differential diagnosis along with other infectious diseases or lymphomas.

AIDS-Related Opportunistic Infections↗