Search PubMed⌕ Search

Biomedical subjects

P Mirk

Publications and source records attributed to P Mirk.

At least 37 records · Page 2Linked to original sources

[Biliodigestive anastomoses on echography. The normal and pathological aspects].

The normal and pathological US features of different types of bilioenterostomy (hepaticojejunostomy, choledochoduodenostomy, polyductal bilioenteric anastomosis) are described, as observed in a prospective study of 27 patients, for a total number of 35 (18 normal and 17 abnormal) examinations. For 20 patients with hepaticojejunostomy, the bilioenteric anastomosis was identified on 13/13 normal examinations and 10/12 pathological examinations. For 2 patients with choledochoduodenostomy, the bilioenteric anastomosis was identified on 2/2 examinations. For 5 patients with polyductal bilioenteric anastomosis (each patient having 2 or 3 anastomoses), all surgical anastomoses were separately identified on 6/8 examinations; as for the remaining 2 patients, 2/3 and 1/3 anastomoses were seen. An abnormal condition was correctly recognized in all the 11 patients with local disease (lithiasis and benign biliary stricture, 2 patients; benign biliary stricture, 5 patients; primary cholangiocarcinoma, 1 patient; recurrent malignancy, 3 patients); in 1 patient, parenchymal and biliary abnormalities due to vascular obstruction were misinterpreted as a result of benign stricture. US can demonstrate the surgical anastomoses between the resected common bile duct or second order intrahepatic ducts and the jejunal loop, with typical features according to the type of surgery performed. Knowledge of such normal appearances after bilioenteric surgery is mandatory in order to detect and correctly evaluate such possible abnormalities at this site as lithiasis and benign or malignant strictures.

Adult↗

Sonographic patterns in splenic infarct.

The sonographic findings in eight cases of splenic infarct at their onset and at different phases of their development have been retrospectively analyzed. A wide range of appearances was seen (single or multiple, rounded or wedge-shaped, echo-free, hypoechoic, and hyperechoic lesions). In our opinion, such variable appearances are related to the age of the infarct (hypoechoic or echo-free in the earlier stages, hyperechoic in healed infarcts). A presumptive diagnosis is possible in the earlier stages since the detection of changes (in echogenicity and/or in size) over a period of time strongly suggests an infarct. On the other hand, a hyperechoic wedge-shaped lesion is fairly typical of healed infarcts.

Adult↗

The thyroid gland with low uptake lesions: evaluation by ultrasound.

An ultrasound examination was performed in 401 patients who had isotopically cold, solitary lesions of the thyroid gland. Of the parameters studied, the level of echoes was the most useful in making the sonographic diagnosis: the rate of malignancy was extremely low both in hyperechoic and echo-free lesions. The presence of a peripheral, complete "halo" appeared to be helpful in differentiating benign lesions from malignant lesions. Approximately 20-25% of the lesions thought to be solitary on the radionuclide study were found to be multinodular on US. When fine-needle aspiration biopsy was used with US the need for surgical exploration of the thyroid gland was obviated in selected cases.

Adenocarcinoma↗

Ultrasonographic patterns in hepatic hemangiomas.

Twenty-one cases of hepatic hemangioma were examined by ultrasound, and three main sonographic patterns were identified. In 14 cases hyperechoic focal areas were observed, in five cases larger hemangiomas exhibited a complex pattern, and in two cases hemangiomas appeared as rounded sonolucent areas with distal enhancement mimicking cysts. Hemangiomas may have significantly variable ultrasonographic features. According to the authors' experience, only in cases of hyperechoic well-defined lesions in asymptomatic patients can a definite diagnosis of hemangioma be made.

Adult↗

Pancreatic cystadenocarcinoma: diagnostic problems.

Eleven cases of pancreatic cystadenocarcinoma were studied with respect to the differential diagnosis from that of pancreatic pseudocysts, using diagnostic ultrasound as the initial investigative technique. Most of the cases presented an ultrasonic picture that correlated well with the gross pathology, but this correlation was not reliable enough to be considered characteristic in differentiating such masses from pseudocysts. The authors divide the cystadenocarcinomas of the pancreas into four echographic classes. In all but one of the classes, diagnostic ultrasound was insufficient by itself to render an accurate diagnosis. In such cases other techniques, i.e. CT, tissue biopsy, and especially angiography, were required for a reliable diagnosis.

Adult↗

[Echography inthe study of the gallbladder wall].

In 511 patients with clinical symptoms of chronic or acute biliary disease, gallbladder area was studied by automatic equipments. In 39 patients different features of the gallbladder wall lesions were demonstrated, in some cases associated with gall stones or bile modifications. Gallbladder wall lesions were divided in three different groups, diffuse, localized or both, according to their appearance and extension. Correlations between the echographic patterns and the clinical and pathological pictures were established. The authors concluding stress the diagnostic value of cholecystosonography in detecting wall lesions such as chronic or acute cholecystitis, cholecystosis and gallbladder tumours. The indications of cholecystosonography are in such a way extended well beyond the demonstration of gallstones and bile modifications to the diagnosis of chronic and acute cholecystitis.

Cholecystitis↗

Bilateral pseudocystic pheochromocytoma.

A case of bilateral pheochromocytoma presenting as primarily cystic suprarenal masses is reported. The computed tomographic manifestations, possible etiology, and differential diagnosis of these cystic suprarenal lesions are discussed.

Adrenal Gland Diseases↗

Sonographic patterns of the gallbladder in acute viral hepatitis.

Ultrasound was used for a serial evaluation of gallbladder modifications in 61 patients with acute viral hepatitis during both the acute phase of the illness and recovery. Most of the patients studied within 7 days from the onset of symptoms and/or jaundice showed sonographic abnormalities of the gallbladder (increased wall thickness, reduced volume, abnormal bile content). A normal ultrasound pattern of the gallbladder was progressively restored during the clinical recovery in most of the patients. A statistical correlation was found between the gallbladder wall thickness and the alanine transferase index.

Acute Disease↗

Sonography of normal lower ureters.

The sonographic features of normal lower ureters, visualized during routine examination of the pelvis in a series of 40 patients, are described. A comparison with the corresponding excretory urogram was obtained in 18 patients. In the authors' experience, visualization of the ureters is a normal finding that should not suggest stasis or dilatation. Recognition of the ureters, although restricted to the lower segment, can be useful in the evaluation of patients examined for recent or current renal colic in order to assess with greater accuracy the existence of ureteral stones and their position. In addition, knowledge of normal features and of physiological changes could presumably be used in the evaluation of pathological conditions, congenital or acquired, of the ureters.

Adult↗

Duplex-Doppler evaluation of intestinal peristalsis in patients with bowel obstruction.

Duplex-Doppler was used to visualize intestinal peristalsis in 30 patients with intestinal distension. The series included 12 patients with acute mechanical obstruction, 13 with long-standing mechanical obstruction, and five with paralytic ileus. The Duplex-Doppler recordings showed several patterns characterized by different degrees of intensity and frequency of the signals according to the type of obstruction, its duration, and the site of Doppler sampling relative to the obstructed segment. Duplex-Doppler evaluation provided both qualitative and quantitative data about intestinal peristalsis, allowing differentiation between mechanical and paralytic ileus. The visualization of intestinal segments having different degrees of peristaltic activity proved useful in localizing the site of mechanical obstruction.

Acute Disease↗

Sonographic and Doppler assessment of the inferior mesenteric artery: normal morphologic and hemodynamic features.

BACKGROUND: We wanted to evaluate prospectively the feasibility of sonographic and Doppler assessment of the inferior mesenteric artery (IMA) and to provide data on its normal morphological and hemodynamic characteristics. METHODS: Sonography and Doppler study of the IMA were performed on 116 patients without splanchnic vessel pathology. Vessel diameter, systolic, diastolic, and time-averaged mean flow velocities, pulsatility index values, and flow volumes were correlated with patient age (< 50 years vs. > or = 50 years) using the Wilcoxon rank-sum test. Findings were verified by splanchnic angiography in 11 cases. RESULTS: Technically valid studies were obtained in 103/116 cases (88.8%). Flowmetric data showed high peripheral resistance (mean +/- SD: systolic flow velocity, 1.41 m/s +/- 0.48; minimal diastolic flow velocity, 0.10 m/s +/- 0.16; pulsatility index, 3.49 +/- 0.49). Mean flow volume calculated in 80 cases was 0.13 L/min +/- 0.06. Older subjects presented significantly higher time-averaged mean flow velocities and lower resistance than those younger than 50 years. CONCLUSIONS: The success rate for sonographic and Doppler study of the IMA is similar to that observed with larger splanchnic vessels. Knowledge of its normal characteristics is necessary for recognition of pathological conditions and for studies of its physiological behavior.

Adolescent↗

Uterine intracavitary disorders: role of sonography and combination with other radiologic techniques.

Since it serves as the site for the implantation of the fertilized ovum, it is evident that significant disorders in the uterine cavity and endometrial mucosa represent potential factors of sterility/infertility. Among the acquired pathological conditions, a possible cause of sterility, there are inflammatory (endometritis) or post-traumatic (synechiae) disorders and proliferative mucosal (endometrial hyperplasia, polyps) and muscular (fibroma) disorders. Sonography (by transabdominal or preferably endovaginal route, and sonohysterography) is the first choice procedure being in most cases adequate for clinical assessment. According to the specific disease, the diagnostic combination with hysteroscopy, hysterosalpingography, Magnetic Resonance Imaging can be suitable.

Female↗

Ovarian factor infertility.

The diseases of the ovary which most frequently cause infertility are: anovulation from follicular atresia, the empty follicle syndrome, the luteinized unruptured follicle syndrome; chronic anovulation syndromes, within which polycystic ovarian syndrome plays a major role; ovarian endometriosis. Sonography and Color Doppler US are the first choice procedures in the monitoring of ovarian cycles, which combined with serum hormone values, are able to identify possible changes in the physiologic sequence of the cycle. In follicular atresia, ovaries with minute follicles (3mm or less) and early disappearance of primary follicle are observed on sonography. The empty follicle syndrome characterized by the lack of oocytes within the primary follicle, is of difficult sonographic diagnosis, a possible sign being the missed visualization of cumulus oophorus. The luteinized unruptured follicle syndrome consists in the absence of oocyte expulsion from primary follicle persisting more than 48 hours after LH blood peak. Doppler spectra of blood flow in perifollicular ovarian arteries maintain the features of the follicular phase, i.e. low diastolic velocities and high resistances. Among chronic anovulation syndromes, hyper-and hypogonadotropism cause ovarian amenorrhea where ovaries are similar to those of women in menopause: small size, very few or absent follicles. The polycystic ovarian syndrome is characterized by an abnormal pulsatile GnRH release which causes LH hypersecretion and FSH hyposecretion. The latter is not able to stimulate the growth and maturation of follicles, while the former causes hyperandrogenism with hirsutism and obesity and is responsible for hypertrophy and stromal hyperechogenicity. The sonographic diagnosis of polycystic ovarian syndrome is based on standardized morphostructural signs as increased volume of the ovaries (> 10 cm3), the presence of numerous (> or = 10) peripheral microfollicles (< or = 5 mm) with hyperechoic stroma. The endometrial cyst, usually present in ovarian endometriosis is visualized with sonography as a round neoformation with ill-defined walls, filled with a uniformly hypoechoic, corpuscular, partly hemorrhagic fluid; less frequently the appearance is that of a more complex structure posing differential diagnostic problems, mainly with the hemorrhagic corpus luteum; both pathological conditions appear poorly vascularized at Color Doppler, with tracings of high resistance arterial flow. Among the procedures of second choice, CT can show the high blood density common to the two conditions while on MRI the signal is mostly hyperintense in T1-weighted sequences with areas of lower signal intensity in T2-weighted sequences.

Female↗