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Biomedical subjects

K D Hopper

Publications and source records attributed to K D Hopper.

At least 91 records · Page 5Linked to original sources
PubMed1991

The pattern of intrathoracic Hodgkin's disease assessed by computed tomography.

Computed tomography (CT) was used to define the sites of intrathoracic abnormality in Hodgkin's disease, determine a pattern of progression of disease in the thorax, and establish the place of this pattern of spread in the differential diagnosis of thoracic abnormalities. One hundred eight patients with newly diagnosed Hodgkin's disease were studied by chest CT. Seventy-seven patients had intrathoracic abnormalities. The pattern seen was one of contiguous spread from the anterior mediastinal/paratracheal area to the other mediastinal lymph node groups (aortopulmonary, subcarinal, posterior mediastinal, and internal mammary), to the hila, and then into the lung by extension or as discrete nodules. Involvement of the pleura, pericardium, or chest wall occurred only after the anterior mediastinal/paratracheal mass had enlarged to greater than 30% of the thoracic diameter. The probability that this pattern of contiguous lymph node spread occurred by chance alone was very small. Hodgkin's disease spreads from the anterior mediastinal/paratracheal area in a contiguous manner. Exceptions are unusual enough that when they occur, diagnoses other than Hodgkin's disease are more likely.

Adult↗
PubMed1991

Imaging of gallbladder variants.

A wide range of normal gallbladder variations are seen on gallbladder imaging. This essay illustrates the major variations that may be encountered, including anomalies in location, number, and form.

Diagnosis, Differential↗
PubMed1991

The efficacy of transrectal ultrasound and prostate cancer.

An increased interest in the diagnosis and treatment of prostate cancer, particularly in the last few years, is reflected in the literature. Numerous articles have been published since 1980 on the subject of imaging of the prostate gland. This article is a review of transrectal ultrasound and its efficacy in the diagnosis and treatment of prostate cancer. Included is a review of the normal prostate anatomy, typical and atypical sonographic features, clinical and radiographic staging of prostate cancer, efficacy of the digital rectal examination, role of ultrasound in prostate cancer screening, surgical treatment, and radiotherapy of prostate cancer.

Adenocarcinoma↗
PubMed1990

Neurologic manifestations in 18q- syndrome.

We report a mother and son with a deletion at 18q22.3. Both have the typical manifestations of the 18q- syndrome. In addition, both have an action tremor which became apparent in childhood. The mother subsequently developed chorea and dysmetria in late adolescence. Magnetic resonance imaging of their brains showed poor myelination of the central white matter tracts with relatively normal myelination of the corpus callosum. We propose that these neurologic findings are most likely due to a failure of expression of the myelin basic protein gene.

Abnormalities, Multiple↗
PubMed1990

Prostate cancer: comparison of pre-operative 0.35 T MRI with whole-mount histopathology.

Magnetic resonance imaging of the prostate was performed in eight patients prior to radical prostatectomy. The results of the imaging studies were then directly compared to histopathologic findings from whole-mount histologic sections. Magnetic resonance imaging identified 82% of cancers greater than 5 mm in minimal diameter. Cancers were identified as areas of decreased signal intensity compared to the high signal intensity peripheral zone on long TR/TE sequences. Cancers were best detected when they involved the middle level of the gland and the posterior half of the prostate. Of the individual tumors identified by imaging, the amount of tumor involvement was underestimated by 37% and overestimated by 22% by MRI. We conclude that magnetic resonance imaging can identify prostate cancer, but has limitations as a screening modality and in accurately assessing the amount of involvement of the prostate gland by cancer.

Carcinoma↗
PubMed1990

Ethanol embolization of vascular malformations.

Absolute ethanol was used to treat 20 patients with symptomatic vascular malformations (SVMs) (ie, venous malformations, arteriovenous malformations, and congenital and posttraumatic arteriovenous fistulas) in whom previous surgery or standard embolotherapy had failed or who were not candidates for surgery. All large complex lesions required multiple embolizations as staged procedures. Immediate thrombosis was achieved in all patients; complications (13% of cases) were generally minor and were treated conservatively. Follow-up studies, performed in 19 of 20 patients, showed persistent occlusion of the SVM in all cases. Ethanol embolization of SVMs, performed according to strict techniques, has proved efficacious in SVM management and is emerging as a definitive form of therapy.

Adolescent↗
PubMed1990

Osteosarcomatosis.

A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.

Adolescent↗
PubMed1990

Stereotactic breast biopsy with a biopsy gun.

One hundred three patients underwent stereotactic breast biopsy with an 18-, 16-, or 14-gauge cutting needle and a biopsy gun. After biopsy, a localization wire was placed and surgical biopsy performed. There was agreement of the histologic results in 89 cases (87%) including 14 of 16 cancers (87%) (kappa = 0.806). The gun biopsy yielded the correct diagnosis in four cases involving a lesion (including one cancer) that was missed at the surgical biopsy. Nine cases in which the lesion was missed at gun biopsy can be related to insufficient needle size, the greater difficulty in using one of the two stereotactic devices, and early inexperience with the technique. A 14-gauge needle was used in the last 29 biopsies, the results of which agreed with the surgical pathologic findings in 28 cases (97%). With greater experience, stereotactic-guided large-gauge automated percutaneous biopsy may prove to be an acceptable alternative to surgical biopsy in women with breast masses suspected at mammography.

Biopsy, Needle↗
PubMed1990

Efficacy of automated biopsy guns versus conventional biopsy needles in the pygmy pig.

Debate over which biopsy needle is the best has intensified recently with the introduction of automated biopsy guns including the 18-gauge long-throw and short-throw Biopty, the 18-gauge Cook, and the 14- and 18-gauge Klear Kut. To evaluate the efficacy of these mechanized biopsy guns versus that of conventional manual biopsy needles in the acquisition of adequate tissue for histopathologic evaluation, open hepatic and renal biopsies were performed in 15 pygmy pigs. The specimens were evaluated separately in a double-blind fashion by two histopathologists using graded criteria. Overall, the best results were obtained with the manual 14-gauge Tru-Cut needle, the long-throw 18-gauge Biopty gun, and the 18-gauge Cook biopsy gun. By comparison, the aspiration-type needles did not perform as well when considered as a group. Several other needles scored well in the biopsy of either the liver or kidney, but not in both. Disappointing results were obtained with the Klear Kut guns (both 14- and 18-gauge) and the Vacu Cut and PercuCut needles.

Animals↗
PubMed1990

The posterior intercostal approach for percutaneous renal procedures: risk of puncturing the lung, spleen, and liver as determined by CT.

A posterior intercostal approach is commonly used for percutaneous access to the upper poles of the kidney. However, the safety of this approach with respect to puncturing the intervening lung, pleura, liver, and spleen with the needle has been inferred only from a small series of patients without regard to the degree of respiration. To determine the possibility of puncturing these structures, we performed CT at both maximal inspiration and expiration and with sagittal reconstructions in 43 (27 supine and 16 prone) randomly selected patients. With expiration, the needle path was such that there was little risk to the spleen and liver from an 11th-12th posterior intercostal approach. However, the chance of transgressing the lung with this approach to the kidney was 29% on the right and 14% on the left. If done during maximal inspiration, the lung would be in the path of the needle in most patients. With a 10th-11th rib posterior intercostal approach, the chance of puncturing the lung was excessive regardless of the degree of respiration used. Our results show that the primary risk from a posterior 11th-12th rib intercostal approach to the upper renal collecting system is puncture of intervening lung, a complication that can be expected to occur in from 14% to 29% of patients. The risks from a posterior 10th-11th rib intercostal approach appear prohibitive.

Adult↗
PubMed1990

The significance of necrotic mediastinal lymph nodes on CT in patients with newly diagnosed Hodgkin disease.

Necrosis in lymph nodes shown on CT in many patients with nodal metastases may indicate that the primary tumor is aggressive and has a high degree of malignancy. However, the significance of nodal necrosis in patients with mediastinal Hodgkin disease remains uncertain. We studied the thoracic CT scans of 76 patients who had newly diagnosed Hodgkin disease with mediastinal involvement with respect to the presence of necrosis (low attenuation, complex, fluidlike areas), the size and volume of the mass, the sites involved, extension ("E" disease), and the patients' clinical response to treatment. CT scans showed necrotic nodes in 16 patients (21%). The difference between these patients and those without necrotic nodes was not statistically significant with respect to sex, age, stage, distribution of disease, presence of E disease, cell type, mass diameter, or the presence of bulk disease (mass diameter/maximal thoracic diameter greater than or equal to 0.33). The mass volume as measured by CT was not significantly (p = .08) larger (1274 cm3) than the group without necrotic nodes (876 cm3). An analysis of the various mediastinal sites involved showed no difference between patients with and without necrotic nodes. Lastly, the presence of necrotic nodes had no significant impact on patients' clinical response to treatment or survival. The presence of mediastinal necrotic nodes appears to have little radiologic or prognostic significance in patients with newly diagnosed Hodgkin disease.

Adult↗
PubMed1989

The role of computed tomography in the evaluation of Caroli's disease.

Two patients with Caroli's disease are reported who did not have renal abnormalities or hepatic fibrosis. Extra hepatic complications of Caroli's disease in these two patients were best evaluated by computed tomography (CT). Although ultrasound evaluates the ductal abnormalities of Caroli's disease well, it does not delineate subphrenic or subhepatic abscesses, pancreatitis, pancreatic phlegmon, or pseudocysts as well CT.

Adult↗
PubMed1989

Renal excretion of endoscopic retrograde cholangiopancreatography injected contrast. A common phenomenon.

The renal excretion of contrast injected during endoscopic retrograde cholangiopancreatography (ERCP) has been described as an uncommon event. Patients with this phenomenon have been considered at increased risk of acute pancreatitis, but idiosyncratic reactions from this intravascular contrast have been discounted as nonexistent. Thirteen patients underwent noncontrast abdominal computed tomography (CT) before ERCP and noncontrast CT plus abdominal radiography immediately after ERCP. Renal excretion of ERCP-injected contrast was seen in two patients on abdominal films and in nine patients by CT. All patients had normal renal function and none developed clinical pancreatitis. Renal excretion of ERCP-injected contrast is much more common than previously suspected. Iodine allergy and possible reaction should be considered when performing this procedure.

Adult↗
PubMed1989

Percutaneous transluminal aortic angioplasty: techniques and results.

Percutaneous transluminal angioplasty of the infrarenal abdominal aorta has been reported by a few authors. In the present series, aortic stenoses in 32 patients were treated with various percutaneous angioplasty techniques. Isolated aortic stenoses and primary aortic stenoses extending into the iliac arteries were successfully dilated. The initial success rate was 100%, without evidence of rupture, thrombosis, dissection, or distal embolization. In only three of the 28 patients who returned for follow-up did symptoms recur or noninvasive vascular laboratory indexes deteriorate (mean follow-up, 25 months). Percutaneous transluminal aortic angioplasty has proved safe and efficacious in the treatment of atherosclerotic aortic stenoses.

Adult↗
PubMed1989

Symptomatic vascular malformations: ethanol embolotherapy.

Absolute ethanol was used to perform nine transcatheter embolizations and 21 direct percutaneous puncture embolizations in eight patients with unresectable vascular malformations. Six patients had arteriovenous malformations and two patients had hemangiomas. Four of these patients had undergone unsuccessful surgery, and the other four were not considered candidates for operation. All large complex symptomatic vascular malformations (SVMs) required multiple embolizations that were staged procedures. Ethanol embolotherapy, performed according to strict techniques, has proved efficacious in the management of SVMs.

Adult↗
PubMed1989

Informed consent for intravascular administration of contrast material: how much is enough?

To determine the usefulness of informed consent prior to the intravascular administration of contrast material, the authors evaluated four equal groups of patients with different degrees of counseling concerning risks and risk factors. Group 1 was given no information. Group 2 was informed of the common risks in a written statement. Group 3 was informed of all known risks in a written statement. Group 4 was informed of all known risks by means of physician counseling. The average times it took for the technologist (groups 1-3) or the physician (group 4) to counsel the patient and obtain informed consent were 1.7, 6.2, 13.6, and 11.4 minutes, respectively. Counseling by physicians would require approximately 7% of their professional time in a busy radiology department. On a postprocedure test, the patients in groups 1-4 scored on average 38.4%, 68.2%, 63.2%, and 69.8%, respectively. There was no statistical difference in the performance of groups 2-4 on the postprocedure test. If informed consent is to be obtained prior to intravascular administration of contrast material, use of a straightforward written consent form detailing the common risks and risk factors appears to be the best method.

Comprehension↗