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J W Charboneau

Publications and source records attributed to J W Charboneau.

At least 55 records · Page 3Linked to original sources
PubMed1990

Takayasu's arteritis. Carotid duplex sonographic appearance, including color Doppler imaging.

Takayasu's arteritis (also known as pulseless disease, aortoarteritis, and aortic arch syndrome) is a chronic inflammatory arteriopathy that affects the aorta and its main branches as well as the pulmonary arteries. We report the carotid duplex sonographic findings of Takayasu's arteritis in three patients. Takayasu's arteritis can be suspected by noting a long segment of diffuse, homogeneous, circumferential vessel wall thickening in the proximal common carotid artery, resulting in narrowing of the lumen. The internal and external carotid arteries are normal.

Adult↗
PubMed1989

Arteriovenous fistula after biopsy of renal transplant: detection and monitoring with color flow and duplex ultrasonography.

An asymptomatic intrarenal arteriovenous fistula was incidentally discovered by color flow and duplex ultrasonography approximately 2 weeks after a percutaneous biopsy of a renal allograft. On the basis of information obtained from the color flow image and pulsed Doppler analysis, the vascular communication could be characterized without the need for angiographic correlation. The patient was managed successfully with close observation aided by serial ultrasound examinations. Spontaneous resolution of the fistula occurred within 4 weeks after the biopsy and was evident on a follow-up ultrasound examination. Duplex ultrasonography in conjunction with color flow imaging proved to be a valuable noninvasive technique for diagnosing and monitoring this postbiopsy vascular complication.

Adult↗
PubMed1989

Current applications of color Doppler imaging in the abdomen and extremities.

Recent advances in ultrasound technology have resulted in the development of diagnostic instruments that combine cross sectional imaging with spectral and color flow Doppler analysis. These instruments have expanded the role of diagnostic ultrasonography in the assessment of disease states involving the extracranial carotid artery, the peripheral vascular system, and the major abdominal vessels. The current applications of color Doppler imaging (CDI) combined with conventional spectral Doppler are demonstrated.

Abdomen↗
PubMed1988

Reoperative parathyroid surgery.

Reoperation for persistent or recurrent primary hyperparathyroidism immediately connotes a complex clinical management problem. Successful cure of hypercalcemia is less frequent whereas complications are more common compared to initial explorations. Of 212 patients operated on at the Mayo Clinic from 1978 through 1986, 189 (89%) were cured. Sporadic disease, multiple endocrine neoplasia, and familial hyperparathyroidism were found in 183 (87%), 20 (9%), and 9 (4%) patients, respectively. Prior to the most recent reoperation, these patients had undergone from one to five operations. Preoperative localization examinations were performed in 192 patients (91%). Cervical high-resolution, real-time ultrasonography, computed tomography, and thallium-technetium scintigraphy had sensitivity rates of 87%, 56%, and 71%, respectively. When the tumor was localized preoperatively, the operative time and cost were significantly reduced compared to nonlocalized tumors. Cervical reexploration only was required in 154 (72%), combined cervical and mediastinal exploration occurred in 46 (22%), and mediastinal exploration only was performed in 12 (6%). There was no perioperative mortality; permanent hypoparathyroidism developed in 33 patients (16%), and six patients (2.9%) suffered permanent unilateral vocal cord paralysis. Anatomically, the most frequent site to find a missed parathyroid adenoma was in the normal location. The large majority of these glands were removed through a cervical incision although, on occasion, they were retracted from the anterior superior mediastinum or the low tracheoesophageal space. These data confirm that reoperative parathyroid surgery can be performed safely, with a rather high degree of success, but too-frequently results in a lifetime morbidity of hypoparathyroidism.

Adolescent↗
PubMed1988

Insulinoma: the value of intraoperative ultrasonography.

Ideally, surgical exploration for insulinomas would be met with uniform success in both finding and removing the tumor, incurring no postoperative mortality or morbidity. In reality, however, insulinomas remain undetected by even experienced surgeons in 10 to 20% of patients, including present-day series. Additionally, postoperative complications may occur in 10 to 25% of patients, principally related to the pancreatic dissection. Although dispensing with any attempt to preoperatively localize the tumor has been advocated, most authors agree that localization efforts are necessary and helpful. To review the results and surgical implications of current localization techniques, 41 adult patients who were surgically treated for insulinomas at the Mayo Clinic from 1980 through June 1987, were reviewed. Tumor size ranged from 5 mm to 4 cm, and the sensitivity of tumor localization using arteriography, computed tomography, preoperative and intraoperative ultrasonography were 55%, 27%, 59%, and 90%, respectively. Since the introduction of intraoperative ultrasonography into our clinical practice in 1982, all 29 of our adult patients' insulinomas have been identified with a combination of this technique and palpation by an experienced surgeon. There were no false positive interpretations with intraoperative ultrasonography, and tumors were imaged in four patients that were not palpable. In 18 of these 29 (62%) patients, the information gleaned from the images appeared to influence the surgical management. While there is no substitute for exploration by an experienced surgeon, his ability is enhanced by the addition of both preoperative and intraoperative ultrasonography.

Adenoma, Islet Cell↗
PubMed1988

Insulinoma. The value of intraoperative ultrasonography.

After establishing the diagnosis of an insulinoma, most surgeons prefer preoperative localization. Selective arteriography has long remained the gold standard for this purpose, but its use has been met with variable success. Despite various attempts at localization, insulinomas remain undetected in 10% to 20% of patients, and there may be a postoperative complication rate of at least 10% to 25%. To review the results and surgical implications of current localization techniques, 36 adult patients who were surgically treated for insulinomas at the Mayo Clinic, Rochester, Minn, from July 1982 through June 1987 were studied. The sensitivities of tumor localization using arteriography, computed tomography, and preoperative and intraoperative ultrasonography were 53%, 36%, 59%, and 90%, respectively. A subset of 29 patients underwent intraoperative ultrasonography, and all of these patients' insulinomas were identified with a combination of this technique and intraoperative palpation, with nonpalpable tumors being imaged in four patients. In 18 patients (62%), information obtained from the images appeared to influence the surgical management. While there is no substitute for exploration by an experienced surgeon, exploration appears to be enhanced by the addition of intraoperative ultrasonography, particularly during reoperation.

Adenoma, Islet Cell↗
PubMed1988

Magnetic resonance imaging of renal oncocytoma.

Two cases of renal oncocytoma studied by magnetic resonance imaging (MRI) suggest that this new imaging modality may prove useful in the preoperative diagnosis of oncocytoma and its differentiation from renal cell carcinoma.

Adenoma↗
PubMed1988

Localization of pancreatic insulinoma: comparison of pre- and intraoperative US with CT and angiography.

Methods of preoperative radiologic localization of insulinoma were compared in 52 patients, 44 of whom had solitary tumors. Examinations performed in these 44 patients were preoperative ultrasonography (US) in 28, angiography in 26, and computed tomography in 23. Prospective sensitivities were 61%, 54%, and 30%, respectively. Imaging sensitivities were lower for the eight patients with multiple insulinomas. In 28 of the 44 patients, intraoperative US was performed without the examiner being aware of the surgical findings. The sensitivity was 84%. Four insulinomas were not palpable but were visualized sonographically. The combined sensitivity of intraoperative US and surgical palpation for detecting solitary insulinomas was 100%. High-frequency intraoperative US is valuable for detecting occult solitary insulinomas and considerably useful for determining the proximity of insulinomas to the pancreatic and bile ducts.

Adenoma, Islet Cell↗
PubMed1988

US-guided biopsy of neck masses in postoperative management of patients with thyroid cancer.

High-frequency (10-MHz) sonography demonstrated a cervical mass or lymphadenopathy, or both, during postoperative follow-up of 52 patients who had undergone surgery for thyroid cancer. Percutaneous biopsy with ultrasonographic (US) guidance was performed in all 52 masses, 44 of which were nonpalpable. Malignant cells were obtained in 29 biopsies, and the results of 20 biopsies were negative, yielding benign lymphocytes only. Results in three biopsies were nondiagnostic due to hypocellular specimens. Therefore, 94% of biopsy results (49) of 52) were confidently assigned as either positive (56%) or negative (38%) for malignancy. There were no complications. High-frequency sonography can demonstrate clinically occult thyroid bed tumor recurrence and lymph node metastases. US-guided biopsy is an accurate and safe technique to confirm or exclude malignancy in patients at high risk of recurrence of thyroid cancer.

Adult↗
PubMed1988

Gallbladder disease in patients with primary sclerosing cholangitis.

We evaluated the gallbladders of 121 patients who had well-documented primary sclerosing cholangitis. Sonograms, cholangiograms, and CT scans were reviewed, and the findings were correlated with surgical or autopsy findings, when available. Pathologic examination of the gallbladder was available in 55 (45%) of the 121 patients; of these, 49 (89%) had abnormal gallbladders. Ninety-three of the 121 patients had one or more radiologic examinations of the gallbladder: 77 had sonograms, 80 had cholangiograms, and 18 had CT scans. Seventy-five (62%) of the 121 patients had abnormal gallbladders on histologic examination or had positive findings on one or more imaging study. By excluding 25 patients who had histologic changes of borderline significance and/or patients who had thick-walled gallbladders attributable to end-stage liver disease, we concluded that 50 (41%) of the 121 patients had intrinsic abnormalities of the gallbladder. Thirty-two (26%) had gallstones, 18 (15%) had probable primary sclerosing cholangitis involving the gallbladder, and five (4%) had benign or malignant neoplasms. Our study indicates that gallbladder abnormalities are common among patients with primary sclerosing cholangitis, and sonography is the most useful technique for evaluating these conditions.

Adult↗
PubMed1988

Sonographically guided percutaneous biopsy of small (3 cm or less) masses.

Traditionally, sonographically guided percutaneous needle biopsy has been used for the biopsy of large, superficial, and cystic masses. Today, however, many think that small, solid masses also can be biopsied accurately. Real-time sonographically guided biopsies of 126 consecutive solid masses that were less than or equal to 3.0-cm in diameter (less than or equal to 1.0 cm, 24; 1.1-2.0 cm, 42; 2.1-3.0 cm, 60) were performed to diagnose primary or secondary neoplasm. These masses were located in a variety of anatomic regions (abdomen, 92; neck, 31; breast, two; extremity, one). Clear visualization of the biopsy needle was accomplished by continuous real-time monitoring of the needle's position, primarily by using linear, phased-array transducers, large-caliber needles (18- to 19-gauge, when possible), and an echogenic screw stylet inserted coaxially within the biopsy needle. The correct cytologic/histologic diagnosis was established in 91% of the masses (less than or equal to 1.0 cm, 79%; 1.1-2.0 cm, 88%; 2.1-3.0 cm, 98%). No complications other than mild, localized discomfort were encountered. Our experience suggests that sonographically guided biopsy is a highly accurate and safe procedure that can be used to establish the diagnosis in solid masses that are 3.0 cm or less in diameter if proper techniques are used to clearly visualize the biopsy needle.

Biopsy, Needle↗
PubMed1988

Cystic pancreatic tumors: CT and sonographic assessment.

Thirty-five CT scans and 23 sonograms of 45 pathologically proved pancreatic cystic neoplasms (16 microcystic adenomas, 17 mucinous [macrocystic] cystadenomas, and 12 mucinous [macrocystic] cystadenocarcinomas) in 43 patients were retrospectively and blindly reviewed. Radiologic findings and their usefulness in differentiating microcystic from mucinous subtypes were assessed. The number of cysts within the tumors (more than six in microcystic adenomas and six or fewer in mucinous cystadenomas and cystadenocarcinomas) and the diameter of the majority of cysts within the tumor (less than or equal to 2 cm in microcystic adenomas and greater than 2 cm in mucinous tumors) were the most helpful radiologic findings in differentiating tumor types. Calcification was present in 38% of microcystic adenomas, 18% of mucinous cystadenomas, and 8% of mucinous cystadenocarcinomas by CT. Calcification was not definitely identified on any of the sonograms. A central scar was identified in only two (13%) of 16 microcystic adenomas. Blind retrospective review was often able to correctly classify tumors as either microcystic (CT, 93%; sonography, 78%) or mucinous (CT, 95%; sonography, 93%). All tumors with a typical appearance on either CT or sonography were categorized correctly. Cystic pancreatic tumors may be difficult to prospectively separate from other types of pancreatic cysts. Assuming a cystic neoplasm is present, it often can be classified correctly as microcystic or mucinous (macrocystic) by using the above criteria.

Adenoma↗
PubMed1987

Suppressive therapy with levothyroxine for solitary thyroid nodules. A double-blind controlled clinical study.

Thyroid nodules are present in up to 50 percent of adults in the fifth decade of life. Patients are often treated with thyroxine in order to reduce the size of the nodule, but the efficacy of thyrotropin-suppressive therapy with thyroxine remains uncertain. In this study, 53 patients with a colloid solitary thyroid nodule confirmed by biopsy were randomly assigned in a double-blind manner to receive placebo (n = 25) or levothyroxine (n = 28) for six months. Before treatment, pertechnetate-99m thyroid scanning showed that 22 percent of the nodules were functional, 25 percent hypofunctional, and 53 percent nonfunctional. High-resolution (10-MHz) sonography was used to measure the size of the nodules before and after treatment. Suppression of thyrotropin release was confirmed in the levothyroxine-treated group by the administration of thyrotropin-releasing hormone; thyrotropin release was normal in the placebo group. Six months of therapy did not significantly decrease the diameter or volume of the nodules in the levothyroxine group as compared with the placebo group. We conclude that the efficacy of levothyroxine therapy in reducing the size of colloid thyroid nodules is not apparent within six months, despite effective suppression of thyrotropin.

Adult↗