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V Nicolet

Publications and source records attributed to V Nicolet.

16 recordsLinked to original sources

Detection of renal artery stenosis with Doppler sonography before and after administration of captopril: value of early systolic rise.

OBJECTIVE: The goal of this study was to assess the value of quantitative and qualitative analysis of the early systolic rise on Doppler waveforms obtained before and after administration of captopril in patients suspected of having renal artery stenosis. SUBJECTS AND METHODS: Seventy-one hypertensive patients (135 kidneys) were studied with transrenal Doppler sonography. Ninety-six kidneys were studied again after administration of captopril. All patients also underwent renal angiography. All Doppler studies were independently reviewed by two observers. Specific criteria for Doppler waveform patterns that were applied in the detection of renal artery stenosis included acceleration, acceleration time of early systolic rise, differential velocity of systolic rise, and resistive index. These criteria were then correlated with angiography, and receiver operating characteristic curves were generated. RESULTS: On the basis of waveform pattern recognition. Doppler sonograms obtained before administration of captopril had a sensitivity of 81% and a specificity of 98% for the detection of renal artery stenosis greater than or equal to 50%. Sensitivity of Doppler sonography obtained after administration of captopril was 100%, and specificity was 100%. For renal artery stenosis greater than or equal to 70%, sensitivity was 94% and specificity was 89% before administration of captopril. The area under the receiver operating characteristic curve for the acceleration criterion was significantly larger after administration of captopril (p = .009) for the detection of renal artery stenosis greater than or equal to 50%. After captopril administration, an acceleration threshold value of 440 cm/sec2 for early systolic rise was associated with a sensitivity of 100% and a specificity of 94% for the detection of renal artery stenosis greater than or equal to 50%. CONCLUSION: Doppler sonography of the renal arteries performed before administration of captopril appears to be an excellent screening tool in the detection of severe stenosis (> or = 70%). Administration of captopril improves the detection of renal artery stenosis greater than or equal to 50% with Doppler sonography when observers use both morphologic and quantitative criteria.

Antihypertensive Agents

Autosplenectomy in systemic lupus erythematosus.

Autosplenectomy in systemic lupus erythematosus (SLE) is associated with a high mortality rate due to Streptococcus pneumoniae sepsis. We describe 2 patients who developed autosplenectomy in the setting of an acute SLE exacerbation. Followup of both patients 12 and 5.5 years after the initial diagnosis of autosplenectomy revealed persistent absence of the spleen. Pneumococcal vaccine was given to both patients. In contrast with reports describing life threatening infections in 46.7% of asplenic patients with SLE, none developed during prolonged followup of our patients. Our data and review of 13 other patients with SLE with autosplenectomy suggest that the 23-valent pneumococcal vaccine should be given promptly to patients with SLE when a diagnosis of autosplenectomy is established.

Adult

Renal artery stenosis: evaluation of Doppler US after inhibition of angiotensin-converting enzyme with captopril.

PURPOSE: To evaluate the modifications of Doppler ultrasound waveform morphology after inhibition of angiotensin-converting enzyme with captopril to increase the sensitivity of Doppler sonography in detecting renal artery stenosis. MATERIALS AND METHODS: Sixty-two renal arteries were studied in 31 hypertensive patients who underwent Doppler scanning before and 1 hour after administration of captopril prior to undergoing angiography. Pattern recognition criteria were applied to classify the Doppler waveforms as having a normal or pulsus tardus configuration. Doppler scanning results were compared with those of arteriography. RESULTS: On the basis of recognition of the pulsus tardus, precaptopril Doppler scanning showed 13 (68%) of 19 significant renal artery stenoses found at angiography (95% confidence interval, 0.43, 0.85), whereas 19 (100%) of 19 stenoses were detected with postcaptopril Doppler scanning (95% confidence interval, 0.85, 1.0). CONCLUSION: Captopril significantly (95% confidence intervals) increases Doppler scanning sensitivity in detecting renal artery stenoses by inducing or enhancing the pulsus tardus distal to a significant renal artery stenosis.

Adult

Correction of deteriorating renal function by superselective embolization of an arcuate renal artery pseudoaneurysm.

We performed superselective embolization of an iatrogenic pseudoaneurysm of the right kidney that was causing hematuria and deterioration of renal function in a patient with chronic renal failure. An arcuate artery was embolized with absorbable gelatin sponge and a straight embolization wire without significant loss of renal vascularization, thus restoring baseline renal function. To our knowledge the clinical and technical aspects of our case are unique. The technique is described.

Aged

Imaging of the salivary glands.

The most common conditions affecting the salivary glands are calculi, inflammation and tumours. Plain radiography may be useful, especially in showing calculi. Sialography is the examination of choice for inflammatory diseases, whereas ultrasonography, computed tomography and magnetic resonance imaging are particularly useful in evaluating masses in the salivary glands. Radionuclide studies are sometimes helpful in evaluating inflammatory or tumoral diseases. Each technique has its place, and the methods are often complementary. In this review article the authors present the techniques that they use in evaluating diseases of the salivary glands.

Humans

Diffuse metastatic involvement of the breast.

Metastases to the breast are not very common and, according to the recent literature, usually present as nodules, most often single but sometimes multiple, generally without retraction or thickening of the skin. The authors reviewed 21 such cases from the last 15 years. In six patients the metastatic infiltration presented as diffuse thickening of the skin and increased density of the breast, as can be seen in inflammatory diseases or after radiotherapy. In five of these six women lymphangitic spread of the carcinoma was demonstrated by microscopy.

Adult

Thickening of the renal collecting system: a nonspecific finding at US.

The records of 22 patients in whom wall thickening of the renal collecting system was seen at ultrasound (US) were retrospectively reviewed. Wall thickening was found in 15 patients with renal transplants and seven with native kidneys. Severe thickening occurred with transplant rejection, but thickening also occurred with urinary tract infection, reflux, or chronic obstruction in both transplanted and native kidneys. As such, thickening of the renal collecting system seen at US is a nonspecific finding that must be correlated with the clinical and laboratory findings.

Adult

Percutaneous fine-needle aspiration biopsy of the pancreas.

Percutaneous fine needle aspiration biopsy of the pancreas allows to obtain without surgery a tissue proven diagnosis of focal lesions of the pancreas. Ultrasound (US), computed tomography (CT), or fluoroscopy are used to guide the positioning of the needle in the lesion. Various benign and malignant lesions can be diagnosed and the cytologic features of them are presented. The average sensitivity of the technique in the diagnosis of pancreatic carcinoma is 80.5% in the literature. The use of percutaneous fine needle biopsy of the pancreas decreases the number of investigations to be done in a patient with pancreatic disease.

Adenocarcinoma

Unsuspected pheochromocytoma: risk of blood-pressure alterations during percutaneous adrenal biopsy.

Four unsuspected pheochromocytomas were discovered during percutaneous fine-needle biopsy of the adrenal gland under ultrasound (n = 1) and computed tomographic (n = 3) guidance. One patient suffered an acute episode of alternating hypertension and hypotension during the procedure. A second patient had no alterations in vital signs during the procedure but had a severe hypertensive crisis during induction of anesthesia at surgery. Neither biopsy nor surgery affected the vital signs in the other two patients. During biopsy study of adrenal lesions, the possibility of unsuspected pheochromocytoma should be considered, and the interventional radiologist must be familiar with the emergency treatment of hypotensive or hypertensive crises that may occur.

Adrenal Gland Neoplasms

Detection of an asymptomatic gastroduodenal artery aneurysm by real-time and pulsed Doppler sonography.

We describe an asymptomatic gastroduodenal artery aneurysm detected by real-time sonography. This lesion had the ultrasonographic characteristics of an aneurysm except for its unusual location and the absence of turbulent echogenic flow and pulsation. Pulsed-Doppler sonography confirmed the diagnosis by demonstrating bidirectional flow with systolic acceleration in the anechoic portion of the lesion.

Aneurysm

Urinary tract infection in children. A reappraisal of its radiologic investigation.

In a prospective study, 100 children with either an acute or a previous history of urinary tract infection were investigated by intravenous urography, micturition cystourethrography, and ultrasonography. The results from the three diagnostic modalities were compared: The urinary tracts in 59 patients were normal, and revealed some abnormality in 41. Ultrasonography proved to be superior to intravenous urography in outlining renal contours and in detecting subtle cortical changes secondary to urinary tract infection (such as slight increases in cortical thickness and edema or cortical scarring). The mucosa of the renal pelvis and bladder was more easily assessed by ultrasound than by intravenous urography. Both modalities were "equally" accurate in detecting important congenital malformations of the urinary tract. Ultrasound failed to detect 24 of 28 ureters demonstrating reflux on voiding cystourethrography. We propose that carefully performed abdominal ultrasonography can replace intravenous urography in the initial investigation of urinary tract infection in children. It should be done in association with a radiographic or radionuclide voiding cystogram. Intravenous urography would then become a complementary examination for abnormal or problematic patients.

Adolescent

Sonographic appearances of the wall of ovarian dermoid cysts.

A review of the sonograms of 25 patients with proven ovarian benign cystic teratomas was undertaken to study the appearance of the tumor wall. It was partially or completely identified in 12 (48%), being most often thin and hypoechoic, relative to the more echogenic contents of the tumor and of the surrounding tissues. In one patient the dermoid cyst demonstrated a circumferential hyperechoic wall due to a thick layer of adipose tissue. This latter appearance is most specific but is rarely seen in dermoid tumors.

Dermoid Cyst