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J J Cronan

Publications and source records attributed to J J Cronan.

At least 37 records · Page 2Linked to original sources
PubMed1995

Role of the resistive index in the evaluation of acute renal obstruction.

Sonography is well established as a screening tool to evaluate the kidney for the presence of renal obstruction. The role of sonography in the evaluation of acute obstruction is less clear, however. Despite recent reports emphasizing the ability of gray-scale sonography and kidney/urinary/bladder films to screen for acute colic, experience indicates that the sonographic diagnosis of acute renal stone disease may be unreliable. Multiple studies have demonstrated the many potential pitfalls of the sonographic examination for acute obstruction. False-negative studies may result if the kidney is evaluated before hydronephrosis occurs. Conversely, nonobstructive pyelocaliectasis and parapelvic cysts may result in false-positive studies. Because of these sonographic limitations, many imaging practices exclusively have utilized excretory urography for the evaluation of patients with symptoms of renal colic.

Acute Disease↗
PubMed1994

Hepatic cavernous hemangiomas: lack of enlargement over time.

PURPOSE: To determine whether change in size is a characteristic of cavernous hemangioma of the liver. MATERIALS AND METHODS: Twenty-one focal masses in 21 patients were diagnosed as cavernous hemangiomas with imaging-guided percutaneous fine-needle biopsy performed between 2 weeks and 2 months after initial imaging study (computed tomography [CT] or ultrasonography [US]). Follow-up imaging examinations (CT, US, or magnetic resonance imaging plus US) were obtained at 5-84 months in all patients. RESULTS: The cavernous hemangiomas ranged in size from 1.5 to 13.5 cm. At follow-up imaging, 19 (90%) of 21 lesions had not changed in size; the two remaining lesions increased by 1 and 2 cm over 3 and 10 months, respectively. CONCLUSION: The size of the majority of cavernous hemangiomas remains stable for periods of follow-up ranging from 5 to 84 months. Growth of these lesions is not characteristic and, when it occurs, should prompt reassessment of the diagnosis.

Female↗
PubMed1994

Cavernous hemangioma of the liver: pathologic correlation with high-field MR imaging.

OBJECTIVE: MR imaging is used to characterize cavernous hemangiomas of the liver because these neoplasms have a long transverse relaxation time compared with normal liver parenchyma and other hepatic neoplasms. The purpose of this study was to correlate the pathologic findings of hemangiomas with their appearance on high-field MR images and with mean T2 relaxation time. MATERIALS AND METHODS: Tissue cores were obtained by percutaneous needle biopsy of 14 cavernous hemangiomas, ranging in size from 1.0 to 10.9 cm. Mean relaxation time was determined from T2-weighted spin-echo MR images. Pathologic analysis included quantification of endothelial cells, identified by counterstaining to anti-factor VIII antibody. RESULTS: We found an inverse relationship between the number of endothelial cells in the histologic specimen and the mean T2 value of the tumor (r = -.75; p < .002). Pathologic examination of tissue from three tumors with the shortest T2 relaxation times showed relatively greater amounts of connective tissue and more numerous but small and compressed vascular channels. Although the two hemangiomas less than 2 cm in diameter had T2 times less than 80 msec, no significant relationship between tumor size and relaxation time was found. CONCLUSION: We conclude that T2 relaxation time of cavernous hemangioma is directly related to the collective size of its constituent vascular spaces. We found no statistically significant difference in measured T2 relaxation time and no difference in histologic appearance between hemangiomas smaller than 2 cm and larger tumors.

Biopsy, Needle↗
PubMed1994

Color Doppler sonography: an adjunctive technique in assessment of parathyroid adenomas.

In evaluating primary parathyroid adenomas with high-resolution color Doppler sonography, initial detection relied on the observation of a hypoechoic soft tissue mass adjacent to the thyroid gland. Using color Doppler sonography, many adenomas had a demonstrable blood supply from the inferior thyroidal artery branches, identified as a vascular arc surrounding the gland from 90 to 270 degrees. The vascular arc assists the interpreter with establishing the nature of the mass, differentiating it from masses such as regional lymph nodes, which demonstrate hilar flow. Sixty-three percent (20 of 32) of parathyroid adenomas had a color arc. The identification of a vascular arc is a useful adjunctive finding, improving diagnostic specificity and quickly confirming the diagnosis of parathyroid adenoma.

Adenoma↗
PubMed1994

Diffuse echoes within a simple hydrocele: an imaging caveat.

Low-level swirling echoes were noted in scrotal fluid that ultimately proved to be a hydrocele. This sonographic appearance is similar to a hematocele or pyocele and potentially can cause confusion. We evaluated 14 patients with hydroceles and found these swirling echoes in nine. In each of these patients, the echoes were readily apparent with increased gain and were distinguished from artifact by their motion. We analyzed the fluid from one hydrocele and found high protein levels. We propose that protein aggregates account for these echoes. This appearance should not be confused with that resulting from a traumatic or infectious cause.

Adult↗
PubMed1994

Vascular ultrasound in the intensive care unit.

Ultrasonography plays an increasingly important role in the evaluation of the vascular system. It is especially useful for the intensive care patient because of its ability to be performed at the patient's bedside, as well as the relatively high frequency of vascular complications in the ICU. Ultrasonography is the method of choice for evaluation of deep vein thromboembolic disease of the lower extremity in all patients, demonstrating excellent sensitivity and specificity for this condition. It also should be the initial method of evaluating upper extremity deep vein thrombosis. It may be limited in this assessment, however, because it does not reliably demonstrate the central subclavian and innominate veins, and therefore may be inadequate for evaluation of malfunctioning central venous catheters. Ultrasonography can reliably identify the presence of abdominal aortic aneurysms, although computed tomography is better able to demonstrate location and extent of these lesions. Finally, ultrasonography can be used to diagnose complications of arterial catheterization and, in selected patients, may direct compression of pseudoaneurysms, resulting in thrombosis and thereby averting surgical repair.

Critical Care↗
PubMed1993

Percutaneous needle biopsy of hepatic cavernous hemangioma.

In a retrospective review of percutaneous needle biopsy in 38 patients, we assessed the safety of this procedure for establishing the diagnosis of cavernous hemangioma of the liver. Computed tomography (CT) or ultrasound was used to direct the biopsy of focal liver lesions ranging in size from 1 to 13.5 cm, with a median size of 3 cm. In all patients, the pathological diagnosis was established conclusively on the basis of core tissue samples obtained using a 20-gauge cutting needle and an average of 2.7 passes. Biopsy was performed as an outpatient procedure in 31 patients (82%). Clinical or radiological follow-up of 30 patients for an average of 32 months (range 7-57 months) supported the pathological diagnosis of cavernous hemangioma. Despite the reported risk of hemorrhage, we performed biopsies on all patients without serious complication; five patients complained of transient right upper quadrant pain, that did not require treatment. We conclude that percutaneous needle biopsy (PNB) of the liver is a safe and effective procedure for establishing the diagnosis of cavernous hemangioma in patients who have no bleeding diathesis.

Adult↗
PubMed1993

Venous thromboembolic disease: the role of US.

Deep vein thrombosis (DVT) is a ubiquitous process that in the acute setting can lead to pulmonary embolism. Chronically, permanent changes that develop within the venous system following an episode of DVT can produce the postphlebitic syndrome, which is associated with pain, swelling, and ulceration. The postphlebitis syndrome can often mimic acute DVT or coexist with it. The clinical evaluation of DVT is ineffective and necessitates a reliable noninvasive diagnostic technique. Compression ultrasound (US) has proved to be the diagnostic method of choice for detection of extremity clot. Femoral and popliteal veins are routinely evaluated for acute clot, but uncertainty exists concerning the need to evaluate the calf veins similarly. US also can be used to diagnose chronic venous changes, which are indicated by the presence of incompetent valves and retrograde blood flow. Upper-extremity venous thrombosis, often induced by indwelling catheters, can also be diagnosed with US.

Arm↗
PubMed1993

Varicoceles: postoperative prevalence--a prospective study with color Doppler US.

To define the ultrasound (US) prevalence of varicoceles after surgical repair, 28 postoperative patients underwent color Doppler US. A group of 26 control subjects also underwent color Doppler US to establish the prevalence of varicoceles in the healthy population. Eighteen of 28 (64%) patients who underwent color Doppler US scanning 16.4 months, on average, after varicocele repair had evidence of a varicocele, a number similar to that reported in other series for infertile men before surgery. Dominant veins in the postoperative patients were larger (P < .01) than those in the control subjects. Postoperative improvements in sperm parameters and conception rate in our subjects were 58% and 43%, respectively, consistent with findings reported in the literature. The prevalence of varicoceles detected at color Doppler US in our healthy population was 42% (11 of 26). Physical examination after surgery failed to show a varicocele in 20 of 22 (91%) patients examined. The discrepancy between sperm parameters and the results of color Doppler US and physical examination raises questions about the utility of US as a means of evaluation in the postvaricocelectomy patient.

Adult↗
PubMed1993

Is bilateral lower extremity compression sonography useful and cost-effective in the evaluation of suspected pulmonary embolism?

OBJECTIVE: Because deep venous thrombosis is clinically linked with pulmonary embolism and often treated similarly, we sought to assess the usefulness of obtaining bilateral lower extremity compression sonograms when findings on ventilation-perfusion lung scans indicate a low or indeterminate probability of pulmonary embolism. Demonstration of deep venous thrombosis would provide a rationale for treating both pulmonary embolism and deep venous thrombosis. MATERIALS AND METHODS: Two hundred twenty-three consecutive patients with suspected pulmonary embolism had ventilation-perfusion lung scans and concurrent bilateral lower extremity compression sonograms; 34 also had pulmonary arteriography. RESULTS: In 75 cases, the results of ventilation-perfusion lung scanning indicated an indeterminate probability of pulmonary embolism. Evidence of thrombosis was seen on sonograms in 11 of these 75. In the remaining 64, 17 underwent pulmonary arteriography and four (24%) had pulmonary embolism. Findings on lung scans indicated a low probability of pulmonary embolism in 70 of 223 patients. Evidence of thrombosis was seen on sonograms in 11 of these 70. Five of the remaining 59 underwent pulmonary arteriography and one (20%) had pulmonary embolism. According to the 1993 Medicare Fee Schedule, if all 145 patients whose lung scans were nondiagnostic had sonography and only those with normal sonograms had pulmonary arteriography, the professional and hospital charges would be $359,552. If all 145 had pulmonary arteriography without sonography, the charges would be $395,031. CONCLUSION: If ventilation-perfusion lung scans indicate a low or an indeterminate probability of pulmonary embolism and bilateral lower extremity compression sonography is performed, only those patients with normal sonographic findings would need further study. Thus, 15% (22/145) of patients could be spared pulmonary arteriography, and the estimated savings in cost would be 9%.

Algorithms↗
PubMed1992

Contemporary concepts for imaging urinary tract obstruction.

Ultrasound is an integral tool in the contemporary assessment of urinary tract obstruction. Pulsed and color Doppler have eliminated many previous false-positives due to blood vessels or non-obstructive hydronephrosis. Limitations of the ultrasound technique still exist and on occasion necessitate the utilization of intravenous urography.

Adult↗
PubMed1992

Ultrasound evaluation of deep venous thrombosis.

Ultrasonography has achieved the role of the contemporary diagnostic tool for the assessment of DVT. Routine use of venography to assess for lower extremity clot is very difficult to justify. Long-term follow-up of patients has provided sufficient documentation that ultrasonography can successfully supplant the venogram. Only with regard to calf vein thrombosis is there still uncertainty about the need to occasionally rely on venography. Radiologists must become cognizant of the capabilities of ultrasonography and facile in its interpretation. Performance of this test should be available in every institution. The nonradiological literature is replete with articles documenting the use of venous ultrasonography and encouraging its routine use for venous clot evaluation.

Humans↗
PubMed1992

Percutaneous drainage of 335 consecutive abscesses: results of primary drainage with 1-year follow-up.

Retrospective review of percutaneous abscess drainage (PAD) of 335 abscesses in 323 consecutive patients was undertaken. Particular attention was directed to body location, associated organ system, communications and fistulae, and to the underlying immunologic status of the patient. One-year follow-up was available in all patients. Overall, the cure rate was 62.4% (209 of 335 abscesses), with a failure rate of 8.95% (30 of 335 abscesses). There were 14.2% (46 of 323 patients) deaths in the follow-up period, of which 4.6% (15 of 323 patients) were believed attributable to sepsis or septic complications. The overall complication rate was 9.8% (33 of 335 abscesses), most of which were minor in nature. For the patient exhibiting immunocompromise, representing 53.1% (172 of 323 patients) of the patient population, the cure rate was 53.4% (95 of 178 abscesses), which was significantly lower than the cure rate of 72.6% (114 of 157 abscesses) for the immunocompetent patient population (n = 151) (P less than .001). The recurrence rate was 2.1% (seven of 335 abscesses), with all recurrences within 3 months of initial drainage. PAD is effective and permanent treatment for both immunocompromised and immunocompetent patients.

Abscess↗
PubMed1992

Compression ultrasonography. Treatment for acute femoral artery pseudoaneurysms in selected cases.

Treatment of pseudoaneurysms has traditionally been surgical. We evaluated 12 patients who developed femoral artery pseudoaneurysms after cardiac catheterization. Using color Doppler ultrasonography steady pressure was applied, occluding flow in both the neck and body of the pseudoaneurysm for 10 minute intervals. Six patients were treated successfully. We believe the same technique was unsuccessful in five additional patients because compression of a short (< 5 mm) or wide neck is ineffective. In one patient the pseudoaneurysm thrombosed spontaneously prior to a treatment attempt. We believe compression ultrasonography of pseudoaneurysms should be offered as a therapeutic alternative to surgery in selected cases.

Adult↗
PubMed1992

Venous ultrasonography.

Compression ultrasonography supplemented by pulsed and color Doppler imaging is the diagnostic modality of choice for evaluating lower extremity deep vein thrombosis in symptomatic and asymptomatic high-risk patients. Furthermore, this technique frequently can characterize the clot as occlusive or nonocclusive or acute or chronic and can define the extent of disease. In patients without thrombosis, this modality can suggest an alternative diagnosis in 12% of patients.

Humans↗