Richard H. Cohan

Computed tomography of renal lymphoma

The CT studies of 29 patients with renal or perirenal lymphoma were retrospectively reviewed. Four patterns of disease were identified. Seventeen of 29 patients (59%) had bilateral renal masses. Only seven of these patients had associated enlarged retroperitoneal lymph nodes. Eight patients (28%) had single renal or perirenal lesions adjacent to or contiguous with bulky retroperitoneal lymphadenopathy. Three patients had infiltration of the perirenal space without significant renal parenchymal involvement, and one patient had a solitary renal mass. No patients in this series had diffuse involvement of the kidney without a focal mass. Renal involvement with lymphoma should be considered in any patient who develops multiple homogeneous solid renal or perirenal masses, even in the absence of other retroperitoneal disease.

Extravascular extravasation of radiographic contrast media: Effects of conventional and low-osmolar agents in the rat thigh

We compared the damage resulting from intradermal injection of four commonly used radiographic contrast media in laboratory rats. Sixty percent meglumine diatrizoate (Reno M 60) and ioxaglate (Hexabrix) produced significantly more ulceration and crusting on gross inspection and more necrosis, edema, and hemorrhage on histologic evaluation than iopamidol 300 (Isovue) or 0.9% (normal) saline. Thirty percent meglumine diatrizoate (Reno M Dip) had an intermediate toxicity, resulting in significantly more visible swelling and more microscopically detected hemorrhage than iopamidol or saline, but less ulceration/crusting and necrosis than Reno M 60 and ioxaglate. Since the three contrast agents of similar osmolality produced different degrees of tissue damage, our results suggest that factors other than high osmolality are partially responsible for determining the severity of injuries from extravasated contrast media.

Role of linear tomography in evaluation of patients with nephrolithiasis

One hundred twenty-four consecutive patients with suspected or known nephrolithiasis were referred for evaluation by linear tomography. Renal calculi were detected in 98 patients (79%). Linear tomography revealed more renal calculi than did preliminary KUB films in 46 patients (37%), although in only 10 cases (8%) was the tomogram positive if the KUB was negative. Exact quantification of the numbers and locations of renal stones is important in patients to be managed metabolically, and in those being evaluated in advance of or following percutaneous or extracorporeal lithotripsy.

Povidone-Iodine sclerosis of pelvic lymphoceles: A prospective study

Twelve patients presented for percutaneous catheter drainage of 13 postoperative pelvic lymphoceles. Six patients with 7 lymphoceles were treated with povidone-iodine sclerosis prior to catheter removal. Only 1 lymphocele (which continued to drain large amounts of fluid during and after the sclerosis procedure) recurred. Six patients with 6 lymphoceles had their percutaneous catheters removed without sclerosis. Fluid collections recurred in 3 instances, necessitating repeat percutaneous drainage (2 patients) or surgery (1 patient). Percutaneous therapy is the treatment of choice for patients with postoperative lymphoceles. Povidoneiodine sclerosis is often effective in preventing reaccumulation of fluid once the lymphocele cavity is collapsed.

Infectious complications of percutaneous biliary drainage

The infectious complications of percutaneous biliary drainage were reviewed in 132 patients with obstructive jaundice. Cholangitic or septic episodes occurred more frequently in patients with malignant (54%) than in those with benign (22%) disease, and frequently were not related to catheter insertions or manipulations. The frequency and mechanisms of bacterial colonization of bile and blood in patients with obstructive jaundice before and after biliary drainage are reviewed. The significant morbidity and mortality related to postdrainage infectious episodes is stressed, and the efficacy of antibiotic prophylaxis is discussed. The significant risks and complications of percutaneous biliary drainage must be considered prior to catheter placement, particularly in the most debilitated patients.

Computed Tomography of Primary Retroperitoneal Malignancies

The CT examinations and medical records of 33 patients with primary retroperitoneal malignancies were reviewed. Computed tomography findings were then compared with those from scans performed on 122 patients with non-Hodgkin lymphoma who presented during the same time interval. Primary retroperitoneal neoplasms had three distinct CT appearances. Twenty-one patients (64%) had large soft tissue masses. Seven patients (21%) had masses with fatty density components, and five patients (15%) had tumors that were primarily of water attenuation. With the exception of those liposarcomas that contained recognizable fat, CT could not distinguish among the different cell types. Seventeen patients with non-Hodgkin lymphoma had large dominant retroperitoneal soft tissue masses that resembled primary retroperitoneal malignancies. In most cases, however, CT was able to differentiate these tumor masses from primary retroperitoneal tumors. Although 19 of 20 sarcomas of soft tissue attenuation were heterogeneous, only six of the 17 lymphomas presenting as dominant masses had such an appearance. Computed tomography is extremely helpful in initially evaluating patients with primary retroperitoneal tumors and in assisting the surgeon in planning his or her approach by accurately defining tumor extent.

Ct assistance for fluoroscopically guided transthoracic needle aspiration biopsy

Five cases are presented that illustrate the utility of obtaining limited CT prior to fluoroscopically guided biopsy in patients who have lung or mediastinal lesions that cannot be adequately localized by chest radiography. Each case describes a unique setting in which the CT images facilitate accurate and safe biopsy needle placement. The rare requirement for biopsy using CT alone, which can be considerably more time consuming, is emphasized.

Biliary cytodiagnosis bile sampling for cytology

The records of 121 patients who presented for PTC and biliary drainage within a five-year period were reviewed. Fifty-eight bile samples had been obtained from 38 of these patients for cytologic analysis. Malignancy was detected in 14 of 32 patients with carcinoma (sensitivity 44%). Repeat sampling was positive in four of nine patients whose initial specimen contained no tumor cells. Bile duct carcinoma, pancreatic carcinoma, and metastatic disease were all detected. An approach to biliary cytodiagnosis is offered that, it is hoped, will further minimize future false negative results.

Fine needle aspiration biopsy in malignant obstructive jaundice.

Percutaneous cytodiagnosis of malignancy in patients with biliary tract obstruction is often useful in planning subsequent therapy. Of 121 patients presenting for percutaneous transhepatic cholangiography and biliary drainage, 45 had fine needle aspiration biopsies. Forty-one patients had malignant obstruction of the biliary tree, while benign disease was present in 4 patients. Neoplasia was diagnosed in 12 of 13 patients with bile duct carcinoma, 16 of 22 patients with pancreatic cancer, and 3 of 6 patients with other malignancies. Radiologic biopsy sensitivity was only slightly inferior to surgical biopsy sensitivity in the same patient population. A scheme for biliary cytodiagnosis is presented, which uses a percutaneous approach for patients with suspected pancreatic carcinoma and a transcatheter approach for patients with suspected bile duct carcinoma. The utility of this procedure and the low complication rate are stressed.

Hemiazygos Continuation of a Left Inferior Vena Cava: Ct Appearance

The CT appearance of hemiazygos continuation of a left-sided inferior vena cava is presented along with discussion of associated anomalies.