Pharmacokinetics of Iopentol in Patients with Chronic Renal Failure

Iopentol 350 mg I/ml was injected in doses of 265 to 533 mg I/kg b.w. (mean 417 mg I/kg b.w.) in 10 patients with advanced nondiabetic chronic renal failure (S-creatinine 672 ± 259 μmol/l (mean ± SD)). Urine (10 patients) and feces (7 patients) were collected at 24 h intervals for 5 days after the injection. The elimination of iopentol was delayed. Five days after injection a mean of 54% (range 35–79%) of the dose was recovered in urine, and 11% (0–20%) in feces. Mean elimination half-life was 28.4 h, about 14 times the half-life found in healthy volunteers. The apparent volume of distribution was 0.27 1/kg b.w., indicating distribution only to extracellular fluid. Using renal iopentol clearance as reference value, GFR was overestimated by 40 to 60% with iopentol total clearance, showing extrarenal elimination of iopentol. The difference was most pronounced in patients with low GFR. In conclusion, this study shows an extrarenal elimination of iopentol and demonstrates a substantial increase in the fecal elimination in patients with severe renal failure.

Radiology of the Ileal J-Pouch — Anal Anastomosis (IPAA)

Forty-four consecutive patients operated on with ileal J-pouch-anal anastomosis (IPAA) and diverting ileostomy were examined with barium contrast medium of the pouch before closure of the ileostomy. CT was performed in 4 of the patients. The anatomy of the ileal reservoir as well as complications were assessed. As normal postoperative anatomy we found a “blind loop” at the upper part of the reservoir in 29 patients and a contrast lucency at the anastomosis between the anal channel and the pouch in 5 patients. Complications were revealed at barium contrast medium examinations in 13 patients, including stenoses at the anastomosis between the pouch and the anal channel in 8 patients and fistulas in 5 patients. CT was especially valuable in the exact diagnosis and location of a pelvic abscess in 3 patients, none of which was shown at pouchography.

Computed Tomography after Modified Whipple Procedure with Pancreatic Duct Occlusion

Eighty-two CT examinations performed on 28 patients who had undergone a modified Whipple procedure including pancreatic duct occlusion were reviewed. Reduction of the antero-posterior diameter of the body and tail of the pancreatic remnant was observed on consecutive scans in 8 patients (29%). Decreasing liver attenuation was seen in 4 patients (14%) postoperatively, and pseudocysts in the pancreatic remnant in 6 (21%). In 10 examinations performed because of suspected intraabdominal abscess postoperatively, abscess was diagnosed in 2 patients. In 62 routine follow-up CT examinations, significant positive findings were diagnosed in 5 patients: tumor recurrence or metastases in 4, and a large pseuodocyst in one. CT is of value in the early postoperative phase to reveal postoperative complications and in the follow-up of patients with specific symptoms indicating tumor recurrence or metastases.

CT and Angiography in Chronic Liver Disease

Detailed correlation of CT and angiographic findings in a retrospective analysis of 25 cases of portal hypertension is presented. The largest diameters of the common and proper hepatic arteries, the portal, splenic, and superior mesenteric veins, and perigastric veins were measured by the two methods, including a CT control series of 20 subjects. The splenic transverse diameter was also measured. Portosystemic collaterals and concomitant pathology disclosed by the two methods were compared. A ratio of nearly 1 was found between vessel diameters measured by angiography and CT, and about 1.3 for splenic size, applying uncorrected measures from angiographic films and a vernier caliper on CT studies. The diameters of hepatic arteries, splenic, and superior mesenteric veins and spleens were significantly larger than those of controls. Except for demonstrating arterial details and esophageal varices, CT was found equal or superior to angiography in mapping portosystemic collaterals, and to disclose concomitant pathology.

CT characterization of developmental variations of the paranasal sinuses in cystic fibrosis

Purpose: To describe variations of paranasal sinus development in patients with cystic fibrosis (CF) and in non-CF patients examined for inflammatory sinonasal disease. We focused on anatomic variants that predispose to orbital and cerebral penetration during functional endoscopic sinus surgery (FESS), e.g. hypoplasia of the maxillary sinus and low ethmoid roof.

Material and Methods: One hundred and sixteen CF patients (3-54 years, median 18) and 136 control patients (7-51 years, median 31) were examined with coronal CT of the paranasal sinuses. CF patients were grouped according to number of confirmed mutations: CF-2 (n=70), CF-1 (n=32), CF-0 (n=14). CT images were evaluated with respect to paranasal sinus development, pneumatization variants and bony variants.

Results: Frontal sinus aplasia and maxillary, ethmoid, and sphenoid sinus hypoplasia were markedly more frequent in CF-2 than in control patients. No CF-2 patient had pneumatization variants such as Haller cells or concha bullosa. Low ethmoid roof was seen in 30% of CF-2 children, but in no control children. CF-1 and CF-0 groups had prevalences of aplasia and hypoplasia intermediate to that of CF-2 and control patients.

Conclusion: Genetically verified CF patients had less developed sinuses, lacked pneumatization variants, and more often had anatomic variants that predispose to complications during FESS. Normally developed sinuses and pneumatization variants in some genetically unverified CF patients (CF-1, CF-0) suggest that these patients may be erroneously diagnosed.

Radiologic Approach to Bile Duct Cysts in Adults

Radiologic findings in 7 adult patients with bile duct cysts were reviewed. Endoscopic retrograde cholangiopancreatography (ERCP) was performed in 6 patients, percutaneous transhepatic cholangiography (PTC) in 4, CT and ultrasonography (US) in 4, and angiography in 6. ERCP and PTC were the only methods which exactly showed the extent of the cysts and the anomalous pancreatico-biliary junction present in 5 patients. ERCP and PTC were mandatory for surgical planning and treatment. Pancreas divisum was revealed in 3 patients, all of whom had suffered from acute pancreatitis. Intracystic adenocarcinoma was depicted at cholangiography in 2 patients. US and CT were valuable in showing cystic masses between the pancreatic head and the hilum of the liver, but in no patient was the diagnosis made by any of these methods. Angiography was performed for preoperative vascular mapping.

Outcome after Catheter-Directed Thrombolysis of Occluded Prosthetic Femoropopliteal Bypasses: A prospective study

Purpose: To evaluate the outcome after catheter-directed thrombolysis of occluded femoropopliteal prosthetic bypasses with the distal anastomosis above the knee.

Material and Methods: Twenty-one patients were included in this prospective study. End-hole catheters, a bolus dose and continuous infusion of recombinant tissue-plasminogen activator (rt-PA) were used, with a median total dose of 10 mg (range 7–20 mg).

Results: With an intra-thrombotic position of the catheter, total or subtotal lysis was obtained in 19 of 21 patients (90%). No serious complications occurred. In 9 patients, the stenoses were successfully treated with balloon angioplasty (PTA, n = 5), local thrombectomy/extension of bypass (n = 3), or with a new bypass (n = 1). After a median observation time of 18 months (6–24), 5 patients had open bypass. Re-occlusion occurred in all (6/6) bypasses in which no flow-limiting lesion was discovered, in all (4/4) bypasses treated twice with thrombolysis, as well as in all bypasses in which stenoses had not been adequately treated (3/3). One bypass re-occluded immediately due to poor runoff.

Conclusion: In the present study, 19/21 infra-inguinal prosthetic bypasses were successfully treated with catheter-directed thrombolysis. However, re-occlusion often took place, especially in bypasses without flow-limiting lesions. If re-occlusion occurs in a bypass in which no stenoses were revealed during the primary thrombolysis procedure, a second catheter-directed thrombolytic treatment does not seem to be warranted. Our results confirm that treatment of flow-limiting lesions is a prerequisite for maintaining patency.

Duplex Doppler Sonography and Angiography in the Evaluation for Liver Transplantation

Duplex Doppler sonography (DDS) and angiography were performed in a prospective study comprising 22 adult patients with hepatic failure. The ability of the 2 methods to visualize the different splanchnic vessels was compared, as well as any abnormality in the liver parenchyma and vessels. The purpose of the study was to decide if DDS could replace angiography in the pretransplantation work-up in these patients. The portal vein was correctly identified as open in 20 patients using DDS and in 21 patients at angiography. Portal vein thrombosis in one patient was correctly diagnosed by both methods. The identification of other vascular structures in the upper part of the abdomen, e.g., liver arteries and splenic vein, was demonstrated in 14 and 16 patients respectively at DDS. Hepatoma in one patient was correctly identified by both methods, as well as the presence of ascites. Splenic artery aneurysms were found in 4 patients at angiography, and in none of these was DDS able to show this abnormality. We conclude that abdominal angiography still seems superior to DDS in the evaluation of patients with hepatic failure prior to orthotopic liver transplantation, especially to demonstrate possible splenic artery aneurysms and detailed mapping of the hepatic arteries.

CT and Angiography in Adrenocortical Carcinoma

CT and angiography were performed in 15 patients with adrenocortical carcinoma. The tumors had a mean diameter of 11 cm (range 4–20 cm). At CT, the 8 largest tumors were ill-defined, and in these, the organ of tumor origin could not be established. Angiographically the correct organ of tumor origin was established in all but one patient. It is concluded that CT is excellent in showing the extent of an adrenal tumor, but is often unable to predict the organ of origin in large tumors. Angiography is still of great value in the preoperative work-up in patients with large adrenocortical carcinomas for correct identification of tumor origin and for vascular mapping.

Influence of Renal Angiography in Living Potential Kidney Donors

The angiograms of 258 potential kidney donors were retrospectively reviewed to assess the influence of angiography for deciding whether or not to accept the potential donor for nephrectomy and which kidney to use for transplantation. Twenty-five potential donors were rejected. In only 8 of these was angiography necessary to reveal the pathology. Angiography was found to be important in deciding which kidney to donate. In 81 donors the right kidney was used for donation and in 50 this decision was based on findings at angiography.

CT characterization of inflammatory paranasal sinus disease in cystic fibrosis

Purpose: In patients with cystic fibrosis (CF) the prevalence of paranasal sinus affection approaches 100%. We hypothesized that the hyperviscous mucus reducing mucociliary clearance in CF patients could give sinonasal inflammatory patterns different from those in non-CF patients. We wanted to compare the extent and distribution of paranasal sinus disease and the inflammatory patterns in these two groups of patients.

Material and Methods: One-hundred-and-eight CF patients (3-54 years old) and 79 controls (7-51 years old) with paranasal sinus disease confirmed at coronal CT were compared. The extent of disease was noted for each sinus and summed for all sinuses. Inflammatory patterns were identified and classified into: 1) routine surgery group (sporadic, infundibular and ostiomeatal complex (OMC) patterns) and 2) complex surgery group (sinonasal polyposis and sphenoethmoid recess (SER) patterns).

Results: CF patients had more widespread sinonasal inflammatory changes and more advanced disease for each sinus. Most CF patients displayed sinonasal polyposis and SER patterns while most controls displayed sporadic, infundibular or OMC patterns. As a result, 67% of CF patients were classified to the complex surgery group, compared to only 19% of controls.

Conclusion: The impaired mucociliary clearance in CF causes widespread inflammatory paranasal sinus disease, with inflammatory patterns more often requiring extensive surgery, with a higher risk of cerebrospinal fluid leak or bleeding, or involving areas that are more difficult to reach with the endoscope.

Complementary role of MR imaging of ethmomaxillary sinus disease depicted at CT in cystic fibrosis

Purpose: To assess whether MR imaging can improve characterization of ethmomaxillary opacification diagnosed at CT in patients with cystic fibrosis (CF) in order to select patients that may benefit from functional endoscopic sinus surgery (FESS).

Material and Methods: Sixty-two CF patients (26 females and 36 males) aged 4–50 years (median 20 years) with ethmomaxillary sinus disease at CT underwent MR examination of the paranasal sinuses (coronal T1 and STIR sequences). FESS had been performed in 28 of the patients prior to this study. MR signal intensities were interpreted as mucosal thickening or infectious material, according to a previous study.

Results: Three major maxillary sinus MR patterns could be distinguished: Air-filled, oval-shaped pus-filled, and streaky-shaped pus-filled sinus lumen. For air-filled maxillary sinuses with mucosal thickening, CT and MR imaging were diagnostically equivalent. Where CT showed homogeneous opacification of the maxillary sinuses, MR imaging differentiated between thickened mucosa and pus-filled areas. Patients who had undergone FESS most commonly had air-filled or streaky-shaped pus-filled maxillary sinus lumen. In non-operated patients oval-shaped pus-filled sinus lumen was most common and could occur without ethmoid disease.

Conclusion: MR imaging of the paranasal sinuses can differentiate between infectious material and thickened mucosa and should be used to select CF patients with pus-filled areas that can be eradicated with FESS.

CT Compared to Angiography for Staging of Tumors of the Pancreatic Head

A retrospective study of 32 patients with malignant tumor of the pancreatic head and ampullary region is presented. The aim of the study was to compare the ability of CT and angiography to evaluate the peripancreatic vessels, and to correlate the results of tumor staging based upon CT criteria to angiographic and surgical findings. In 5 patients (16%) CT disclosed contiguous tumor growth around vessels not discernible at angiography and, in contradiction to previous reports, angiography added no valuable information regarding main vessel involvement. In terms of sensitivity, specificity, and positive predictive value CT was more accurate in predicting unresectable than resectable tumors, the former with a sensitivity of 92% and a specificity and positive predictive value of 100%.

CT, MR Imaging and Angiography in Pancreatic Apudomas

Findings at CT, MR imaging and angiography in 29 patients with pancreatic apudomas are presented. CT and angiography were performed in all the patients, MR imaging in 10. Twenty-five patients underwent laparotomy. The ability of the different imaging methods to localize the primary tumor and detect hepatic metastases was compared. CT and MR imaging depicted the primary tumor in 79% and 88% of the cases respectively, angiography in 72%. Enhancement patterns at CT and signal intensity variations at MR imaging were unspecific parameters regarding different types of tumors. CT and MR imaging were considerably more accurate than angiography in evaluating local tumor resectability. Angiography revealed more numerous small hepatic metastases (<0.5 cm) than CT or MR imaging, but missed metastases in the left lobe in 5 patients. MR imaging seems promising in localizing and characterizing pancreatic apudomas, but further evaluation is needed before any conclusion can be drawn. At present dynamic incremental CT seems mandatory in the evaluation of pancreatic apudomas. Angiography is of value for preoperative and preembolization vascular mapping, and in localizing small pancreatic apudomas not shown at CT or MR imaging. Faster dynamic thin slice CT scanning and fast-sequence MR imaging may increase the sensitivity of detecting small primary pancreatic apudomas.

Proposal of a CT scoring system of the paranasal sinuses in diagnosing cystic fibrosis

The purpose of this study was to develop a paranasal sinus CT scoring system that could be used as a diagnostic tool to discriminate cystic fibrosis (CF) patients from control patients examined for sinonasal disease. The model should include as few and easily applicable criteria as possible, supported by statistical analyses and clinical judgement. We used data from 116 CF and 136 control patients. The CF patients were grouped according to the number of confirmed CF mutations: genetically verified (CF-2), or based on sweat testing and clinical findings alone (CF-1, CF-0). Nine paranasal sinus CT criteria, including development, pneumatisation variants and inflammatory patterns, were evaluated. The final model included three criteria: (a) frontal and (b) sphenoid sinus development, and (c) absence of three pneumatisation variants. This model discriminated CF-2 from controls with overlap of summed scores in only 8 of 206 patients. When this model was applied in the CF-1 and CF-0 groups, two populations seemed to exist. A larger group with summed scores overlapping that of the CF-2 group and a smaller group with summed scores overlapping that of the control group. We conclude that this CT scoring system may support, as well as exclude, a CF diagnosis in cases of diagnostic uncertainty.

CT characterization of developmental variations of the paranasal sinuses in cystic fibrosis

PURPOSE

To describe variations of paranasal sinus development in patients with cystic fibrosis (CF) and in non-CF patients examined for inflammatory sinonasal disease. We focused on anatomic variants that predispose to orbital and cerebral penetration during functional endoscopic sinus surgery (FESS), e.g. hypoplasia of the maxillary sinus and low ethmoid roof.

MATERIAL AND METHODS

One hundred and sixteen CF patients (3-54 years, median 18) and 136 control patients (7-51 years, median 31) were examined with coronal CT of the paranasal sinuses. CF patients were grouped according to number of confirmed mutations: CF-2 (n=70), CF-1 (n=32), CF-0 (n=14). CT images were evaluated with respect to paranasal sinus development, pneumatization variants and bony variants.

RESULTS

Frontal sinus aplasia and maxillary, ethmoid, and sphenoid sinus hypoplasia were markedly more frequent in CF-2 than in control patients. No CF-2 patient had pneumatization variants such as Haller cells or concha bullosa. Low ethmoid roof was seen in 30% of CF-2 children, but in no control children. CF-1 and CF-0 groups had prevalences of aplasia and hypoplasia intermediate to that of CF-2 and control patients.

CONCLUSION

Genetically verified CF patients had less developed sinuses, lacked pneumatization variants, and more often had anatomic variants that predispose to complications during FESS. Normally developed sinuses and pneumatization variants in some genetically unverified CF patients (CF-1, CF-0) suggest that these patients may be erroneously diagnosed.

Complementary role of MR imaging of ethmomaxillary sinus disease depicted at CT in cystic fibrosis

PURPOSE

To assess whether MR imaging can improve characterization of ethmomaxillary opacification diagnosed at CT in patients with cystic fibrosis (CF) in order to select patients that may benefit from functional endoscopic sinus surgery (FESS).

MATERIAL AND METHODS

Sixty-two CF patients (26 females and 36 males) aged 4-50 years (median 20 years) with ethmomaxillary sinus disease at CT underwent MR examination of the paranasal sinuses (coronal T1 and STIR sequences). FESS had been performed in 28 of the patients prior to this study. MR signal intensities were interpreted as mucosal thickening or infectious material, according to a previous study.

RESULTS

Three major maxillary sinus MR patterns could be distinguished: Air-filled, oval-shaped pus-filled, and streaky-shaped pus-filled sinus lumen. For air-filled maxillary sinuses with mucosal thickening, CT and MR imaging were diagnostically equivalent. Where CT showed homogeneous opacification of the maxillary sinuses, MR imaging differentiated between thickened mucosa and pus-filled areas. Patients who had undergone FESS most commonly had air-filled or streaky-shaped pus-filled maxillary sinus lumen. In non-operated patients oval-shaped pus-filled sinus lumen was most common and could occur without ethmoid disease.

CONCLUSION

MR imaging of the paranasal sinuses can differentiate between infectious material and thickened mucosa and should be used to select CF patients with pus-filled areas that can be eradicated with FESS.

Outcome after catheter-directed thrombolysis of occluded prosthetic femoropopliteal bypasses. A prospective study

PURPOSE

To evaluate the outcome after catheter-directed thrombolysis of occluded femoropopliteal prosthetic bypasses with the distal anastomosis above the knee.

MATERIAL AND METHODS

Twenty-one patients were included in this prospective study. End-hole catheters, a bolus dose and continuous infusion of recombinant tissue-plasminogen activator (rt-PA) were used, with a median total dose of 10 mg (range 7-20 mg).

RESULTS

With an intra-thrombotic position of the catheter, total or subtotal lysis was obtained in 19 of 21 patients (90%). No serious complications occurred. In 9 patients, the stenoses were successfully treated with balloon angioplasty (PTA, n=5), local thrombectomy/extension of bypass (n=3), or with a new bypass (n=1). After a median observation time of 18 months (6-24), 5 patients had open bypass. Re-occlusion occurred in all (6/6) bypasses in which no flow-limiting lesion was discovered, in all (4/4) bypasses treated twice with thrombolysis, as well as in all bypasses in which stenoses had not been adequately treated (3/3). One bypass re-occluded immediately due to poor runoff.

CONCLUSION

In the present study, 19/21 infra-inguinal prosthetic bypasses were successfully treated with catheter-directed thrombolysis. However, re-occlusion often took place, especially in bypasses without flow-limiting lesions. If re-occlusion occurs in a bypass in which no stenoses were revealed during the primary thrombolysis procedure, a second catheter-directed thrombolytic treatment does not seem to be warranted. Our results confirm that treatment of flow-limiting lesions is a prerequisite for maintaining patency.

Hypoplasia of the sphenoid sinuses as a diagnostic tool in cystic fibrosis

PURPOSE

To measure and compare the size of the sphenoid sinuses in patients with cystic fibrosis (CF) to patients with inflammatory sinonasal disease, and to correlate the size with number of CF mutations in each patient.

MATERIAL AND METHODS

Ninety-six CF patients aged 5-47 years (median 19 years) and 130 control patients aged 7-51 years (median 32 years) were examined using coronal CT of the paranasal sinuses. In each patient, the CT image with the largest coronal area of the sphenoid sinuses was scanned into a Macintosh computer with image processing and analysis software. Largest coronal area and largest circumference of the right and left sphenoid sinuses were automatically measured. Additionally, antero-posterior extension of the sphenoid sinuses was calculated from the lateral scanograms. CF patients were grouped according to number of confirmed mutations (CF-0, CF-1, or CF-2).

RESULTS

CF patients generally had small sphenoid sinuses. The largest differences for all parameters were observed between the CF-2 and the control groups (p<0.0001). No CF-2 patient had pneumatization beyond the presphenoid. The CF-0 and CF-1 groups consisted of two populations, one overlapping the CF-2 group and another overlapping the control group.

CONCLUSION

Hypoplasia of the sphenoid sinuses is a characteristic finding in CF patients. When pneumatization of the basisphenoid is present, the existing CF diagnosis should be questioned.

CT and MR imaging of the paranasal sinuses in cystic fibrosis. Correlation with microbiological and histopathological results

PURPOSE

To compare CT and MR findings of the paranasal sinuses in patients with cystic fibrosis (CF) with microbiology and histopathology. Further, to compare microbiology from the maxillary sinuses, nasopharynx and sputum.

MATERIAL AND METHODS

CT and MR imaging of the paranasal sinuses were performed in 10 CF patients. Endoscopy and maxillary sinus aspirates were obtained (guided by the MR findings) and analyzed microbiologically and histologically. Samples from the nasopharynx and sputum were analyzed microbiologically.

RESULTS

CT and MR were equal in displaying the extent of soft tissue masses, which at CT were homogeneous, while MR showed heterogeneous signals. MR images also demonstrated circumscribed areas with signal void at the STIR sequence with corresponding high to intermediate signal at the T1-weighted sequence. P. aeruginosa was frequently cultured from these areas which we named the "black hole sign". Maxillary sinus cultures revealed the same bacteria as nasopharynx and sputum cultures combined.

CONCLUSION

MR images were superior to CT in differentiating soft tissue masses in the paranasal sinuses in CF patients. Bacteria with potential for specialized iron uptake mechanisms were present in areas with signal void at the STIR sequence. Our hypothesis is that the MR "black hole sign" can be explained by paramagnetic properties related to bacterial agents.

Morphological abnormalities revealed after successful intra-arterial thrombolysis of infra-inguinal native arteries and bypasses

PURPOSE

To characterise morphological abnormalities depicted after successful intra-arterial thrombolysis; to determine whether these differed in infra-inguinal native arteries and bypasses; and to evaluate whether balloon angioplasty was an appropriate treatment of stenoses in the acute phase after thrombolysis.

MATERIAL AND METHODS

Patient records, radiology records, and angiograms from 47 patients with acute or subacute occlusions of infra-inguinal arteries (n = 21) or bypasses (n = 26) successfully treated with continuous intra-arterial infusion of streptokinase, urokinase or tissue plasminogen activator were retrospectively reviewed.

RESULTS

Angiographic morphological abnormalities were depicted in 18 of 21 arteries (86%) and in 23 of 26 bypasses (88%), the most common abnormality being stenoses. Haemodynamically significant stenoses were found in 15 arteries (71%) and 18 bypasses (69%). The majority of the stenoses were successfully treated with balloon angioplasty, both in native arteries (12/15; 80%) and in bypasses (14/18; 78%).

CONCLUSION

Morphological abnormalities are most often shown after successful intra-arterial thrombolysis in arteries, autogenous and non-autogenous bypasses. In all types of conduits, stenoses are the most commonly revealed lesion, which in the majority of cases can be treated with balloon angioplasty. Short-term outcome after catheter-directed thrombolysis and angioplasty seems fair.

Diagnosis of acute left-sided colonic diverticulitis by three radiological modalities

PURPOSE

To compare the findings at US, CT and contrast enema (CE) with the clinical, biochemical, and surgical findings in patients with suspected acute left-sided colonic diverticulitis (ALCD).

MATERIAL AND METHODS

The study comprised 32 consecutive patients hospitalized with clinically diagnosed ALCD. During the first 3 days of hospitalization, they were examined by US and CT of the pelvis and abdomen, and CE.

RESULTS

Of the 32 patients, 21 had ALCD according to the combined radiological, clinical, biochemical and surgical findings. Findings compatible with ALCD were verified by radiological examination alone in 12 patients (4 patients at US, 10 at CT, and 6 at CE). In 9 patients, only diverticula or tethering was found at either CE or CT, and the diagnoses were then supported by clinical and biochemical findings and clinical follow-up. The most common clinical symptoms and signs associated with ALCD were left lower quadrant pain, left-sided tenderness, and fever. Most patients showed elevations of the white blood-cell count, erythrocyte sedimentation rate, and C-reactive protein, but there was no statistical difference in the stages of severity of ALCD, or between ALCD and other abdominal disorders.

CONCLUSION

Radiological examination is valuable in confirming the diagnosis of ALCD. CT was the radiological modality that best demonstrated ALCD and revealed complications (e.g. pericolic abscesses) during the course of the illness.

[Embolization of congenital pulmonary arteriovenous malformations]

Patients with arteriovenous pulmonary malformations are at risk of developing secondary brain disease such as transient ischemic attacks, strokes or abscesses. Lethal haemothorax and haemoptysis also occur. 12 of 14 malformations in five patients were treated using a total of eight procedures. One patient experienced a transient unilateral hemiparesis, otherwise no complications occurred. None of the 43 deployed occlusion coils was lost through the fistulas. Complete occlusion was achieved in all lesions where coils could be placed in a stable position. One patient suffered a minor recurrence. The use of interlocking detachable coils (IDC) which can be retracted or repositioned prior to full deployment is recommended.

Angiography with nonionic X-ray contrast media in severe chronic renal failure: renal function and contrast retention

The effects of contrast media on renal function and the cortical retention of contrast media after abdominal angiography were investigated. Sixteen nondiabetic patients with predialytic chronic renal failure received either the nonionic dimeric contrast medium iodixanol or the monomeric contrast medium iohexol in a double-blind randomized study. All patients were well hydrated before, during and after angiography. Mean 99mTc-DTPA clearance was 14.0 ml/min/1.73 m2 in the iodixanol group, and 9.3 ml/min/1.73 m2 in the iohexol group at baseline. No statistically significant changes were seen after angiography. Serum creatinine increased significantly 48 and 72 h after angiography in both groups, and then normalized. Creatinine clearance was reduced only in the iohexol group, at 72-96 h. The urinary excretion of renal enzymes and of total protein did not change significantly. No patients developed oliguria or required dialysis during the 7-day observation period. Increased attenuation in the renal cortex, measured by computed tomography and probably reflecting intracellular retention of contrast medium, peaked at 24 h, and was observed in both groups during the follow-up period. Thus, although transient and minor changes in glomerular filtration rate were noted, both iodixanol and iohexol were safe for use in angiography in nondiabetic patients with severe chronic failure when the patients were well hydrated.

Interferon-alpha 2b, with or without prior hepatic artery embolization: clinical response and survival in mid-gut carcinoid patients. The Norwegian carcinoid study

BACKGROUND

Mid-gut carcinoid tumours often present with liver metastases, and survival has then been less than 2 years in earlier reports. We have evaluated the effects of interferon therapy on clinical response and survival, with or without hepatic artery embolization in these patients.

METHODS

In a prospective study 30 female and 12 male patients, aged 23 to 75 years, with mid-gut carcinoid tumours and liver metastases underwent surgery with removal of as much as possible of their primary tumour. If technically feasible, embolization of hepatic arteries was performed in the absence of contraindications. Seventeen patients were embolized, and all patients received interferon-alpha 2b treatment for 1 year. Response factors were computer tomography (CT) measurement of the largest liver metastasis and the 24-h urinary excretion of 5-hydroxyindoleacetic acid (5-HIAA). After 12 months patients with objective response or stable disease either continued or withdrew from interferon therapy. Survival was estimated when all patients had been observed for at least 36 months.

RESULTS

Nine patients reduced the dose, and five withdrew from interferon treatment owing to side-effects the 1st year. Three patients died. Fifteen patients (39%) showed objective response 12 months after inclusion. Cumulative 5-year survival estimated from inclusion was 37.5% in all 42 patients but 71.4% in those who continued interferon therapy. The difference in survival between the interferon-treated and those who withdrew from interferon therapy at 12 months was significant when embolization was corrected for in a Cox model (p < 0.0125). The seemingly increased survival in embolized versus non-embolized patients did not reach statistical significance (p = 0.07).

CONCLUSION

Interferon induced an objective response in mid-gut carcinoid patients as judged by the 24-h urinary 5-HIAA excretion. Patients receiving continuous interferon therapy showed improved response and survival compared with patients who stopped the treatment. Regardless of medical therapy, more survivors and more responders, as evaluated from CT measurements, were found among the embolized patients than among the non-embolized. Embolization could, however, not be shown to have a significant effect on survival.

Risk factors in primary sclerosing cholangitis

The increasing use of liver transplantation and new treatment regimens requires an accurate estimate of the prognosis in primary sclerosing cholangitis. To clarify the natural history and prognosis of this disease, we studied the clinical features at the time of presentation and the outcome in 77 consecutive patients admitted to our hospital. The median age at diagnosis of primary sclerosing cholangitis was 32.5 years; 66% of the patients were male; 76 had concomitant inflammatory bowel disease and two had celiac disease. Thirty-four patients were classified as asymptomatic at diagnosis of primary sclerosing cholangitis. The mean follow-up time was 6.2 years; 25 patients have died or been transplanted. Cholangiocarcinoma has been diagnosed in 11 patients (14%). Female patients have a significantly poorer survival rate than male patients. The bilirubin level was found to be an independent risk factor for both mortality/transplantation, and for the occurrence of cholangiocarcinoma. Age at diagnosis of primary sclerosing cholangitis was an additional risk factor of death/transplantation. As bilirubin is an important prognostic factor for the development of both cholangiocarcinoma and death/transplantation, the construction of prognostic indices seems to be of limited value in the timing of transplantation of the individual patient.

[Embolization of traumatic vascular injuries, arteriovenous malformations and tumors]

The article contains a brief survey of the current status of transcatheter embolization of traumatic and iatrogenic vascular lesions, arterio-venous malformations and tumours. Guidelines are suggested for embolization of different lesions is given, with emphasis on indications and contraindications for performing such procedures. Complications following embolization are described. Our own experience of embolization is briefly mentioned. Personally, we have most experience in embolization of liver metastases from neuroendocrine tumours, and some experience of treatment of traumatic vascular lesions and arterio-venous malformations.

Hepatobiliary disease in ulcerative colitis. An analysis of 18 patients with hepatobiliary lesions classified as small-duct primary sclerosing cholangitis

BACKGROUND

The aim of the present study was to describe the characteristics of patients with ulcerative colitis (UC) and hepatobiliary disease that does not satisfy the diagnostic cholangiographic criteria of primary sclerosing cholangitis (PSC) and to compare this group with PSC patients.

METHODS

Among 199 patients with UC admitted to our department during 1986-91, 64 patients had major hepatobiliary disease considered to be associated with the colitis. Biochemical tests, colonoscopy, endoscopic retrograde cholangiography (ERC), and liver biopsy were performed in these 64 patients and in 5 patients from our outpatient clinic.

RESULTS

PSC was diagnosed in 51 patients (group I; 80%). The other 13 patients (20%) and the additional 5 patients (n = 18; group II) all had normal extrahepatic bile ducts. Five patients in group II also had normal intrahepatic ducts, whereas 13 patients had intrahepatic abnormalities. The male to female ratio in group II was 2.0:1. All of them had extensive colitis. The clinical symptoms and the biochemical and histologic findings were quite similar in groups I and II.

CONCLUSIONS

The patients in group II of this study constitute a major group with hepatobiliary lesions associated with UC, amounting to one-fourth the number of PSC patients. They have several similarities with classical PSC of the large bile ducts, and we suggest that they be classified as having small-duct PSC.

Duplex Doppler sonography and angiography in the evaluation for liver transplantation

Duplex Doppler sonography (DDS) and angiography were performed in a prospective study comprising 22 adult patients with hepatic failure. The ability of the 2 methods to visualize the different splanchnic vessels was compared, as well as any abnormality in the liver parenchyma and vessels. The purpose of the study was to decide if DDS could replace angiography in the pretransplantation work-up in these patients. The portal vein was correctly identified as open in 20 patients using DDS and in 21 patients at angiography. Portal vein thrombosis in one patient was correctly diagnosed by both methods. The identification of other vascular structures in the upper part of the abdomen, e.g., liver arteries and splenic vein, was demonstrated in 14 and 16 patients respectively at DDS. Hepatoma in one patient was correctly identified by both methods, as well as the presence of ascites. Splenic artery aneurysms were found in 4 patients at angiography, and in none of these was DDS able to show this abnormality. We conclude that abdominal angiography still seems superior to DDS in the evaluation of patients with hepatic failure prior to orthotopic liver transplantation, especially to demonstrate possible splenic artery aneurysms and detailed mapping of the hepatic arteries.

Radiology of the ileal J-pouch-anal anastomosis (IPAA)

Forty-four consecutive patients operated on with ileal J-pouch-anal anastomosis (IPAA) and diverting ileostomy were examined with barium contrast medium of the pouch before closure of the ileostomy. CT was performed in 4 of the patients. The anatomy of the ileal reservoir as well as complications were assessed. As normal postoperative anatomy we found a "blind loop" at the upper part of the reservoir in 29 patients and a contrast lucency at the anastomosis between the anal channel and the pouch in 5 patients. Complications were revealed at barium contrast medium examinations in 13 patients, including stenoses at the anastomosis between the pouch and the anal channel in 8 patients and fistulas in 5 patients. CT was especially valuable in the exact diagnosis and location of a pelvic abscess in 3 patients, none of which was shown at pouchography.

CT, MR imaging and angiography in pancreatic apudomas

Findings at CT, MR imaging and angiography in 29 patients with pancreatic apudomas are presented. CT and angiography were performed in all the patients, MR imaging in 10. Twenty-five patients underwent laparotomy. The ability of the different imaging methods to localize the primary tumor and detect hepatic metastases was compared. CT and MR imaging depicted the primary tumor in 79% and 88% of the cases respectively, angiography in 72%. Enhancement patterns at CT and signal intensity variations at MR imaging were unspecific parameters regarding different types of tumors. CT and MR imaging were considerably more accurate than angiography in evaluating local tumor resectability. Angiography revealed more numerous small hepatic metastases (< 0.5 cm) than CT or MR imaging, but missed metastases in the left lobe in 5 patients. MR imaging seems promising in localizing and characterizing pancreatic apudomas, but further evaluation is needed before any conclusion can be drawn. At present dynamic incremental CT seems mandatory in the evaluation of pancreatic apudomas. Angiography is of value for preoperative and preembolization vascular mapping, and in localizing small pancreatic apudomas not shown at CT or MR imaging. Faster dynamic thin slice CT scanning and fast-sequence MR imaging may increase the sensitivity of detecting small primary pancreatic apudomas.

CT compared to angiography for staging of tumors of the pancreatic head

A retrospective study of 32 patients with malignant tumor of the pancreatic head and ampullary region is presented. The aim of the study was to compare the ability of CT and angiography to evaluate the peripancreatic vessels, and to correlate the results of tumor staging based upon CT criteria to angiographic and surgical findings. In 5 patients (16%) CT disclosed contiguous tumor growth around vessels not discernible at angiography and, in contradiction to previous reports, angiography added no valuable information regarding main vessel involvement. In terms of sensitivity, specificity, and positive predictive value CT was more accurate in predicting unresectable than resectable tumors, the former with a sensitivity of 92% and a specificity and positive predictive value of 100%.

Pharmacokinetics of iopentol in patients with chronic renal failure

Iopentol 350 mg I/ml was injected in doses of 265 to 533 mg I/kg b.w. (mean 417 mg I/kg b.w.) in 10 patients with advanced nondiabetic chronic renal failure (S-creatinine 672 +/- 259 mumol/l (mean +/- SD)). Urine (10 patients) and feces (7 patients) were collected at 24 h intervals for 5 days after the injection. The elimination of iopentol was delayed. Five days after injection a mean of 54% (range 35-79%) of the dose was recovered in urine, and 11% (0-20%) in feces. Mean elimination half-life was 28.4 h, about 14 times the half-life found in healthy volunteers. The apparent volume of distribution was 0.27 l/kg b.w., indicating distribution only to extracellular fluid. Using renal iopentol clearance as reference value, GFR was overestimated by 40 to 60% with iopentol total clearance, showing extrarenal elimination of iopentol. The difference was most pronounced in patients with low GFR. In conclusion, this study shows an extrarenal elimination of iopentol and demonstrates a substantial increase in the fecal elimination in patients with severe renal failure.

Radiologic approach to bile duct cysts in adults

Radiologic findings in 7 adult patients with bile duct cysts were reviewed. Endoscopic retrograde cholangiopancreatography (ERCP) was performed in 6 patients, percutaneous transhepatic cholangiography (PTC) in 4, CT and ultrasonography (US) in 4, and angiography in 6. ERCP and PTC were the only methods which exactly showed the extent of the cysts and the anomalous pancreatico-biliary junction present in 5 patients. ERCP and PTC were mandatory for surgical planning and treatment. Pancreas divisum was revealed in 3 patients, all of whom had suffered from acute pancreatitis. Intracystic adenocarcinoma was depicted at cholangiography in 2 patients. US and CT were valuable in showing cystic masses between the pancreatic head and the hilum of the liver, but in no patient was the diagnosis made by any of these methods. Angiography was performed for preoperative vascular mapping.

CT and angiography in chronic liver disease

Detailed correlation of CT and angiographic findings in a retrospective analysis of 25 cases of portal hypertension is presented. The largest diameters of the common and proper hepatic arteries, the portal, splenic, and superior mesenteric veins, and perigastric veins were measured by the two methods, including a CT control series of 20 subjects. The splenic transverse diameter was also measured. Portosystemic collaterals and concomitant pathology disclosed by the two methods were compared. A ratio of nearly 1 was found between vessel diameters measured by angiography and CT, and about 1.3 for splenic size, applying uncorrected measures from angiographic films and a vernier caliper on CT studies. The diameters of hepatic arteries, splenic, and superior mesenteric veins and spleens were significantly larger than those of controls. Except for demonstrating arterial details and esophageal varices, CT was found equal or superior to angiography in mapping portosystemic collaterals, and to disclose concomitant pathology.

Iopentol in patients with chronic renal failure: its effects on renal function and its use as glomerular filtration rate parameter

Iopentol (mean dose 0.42 g I kg-1) was administered for abdominal aortography and pelvic angiography in 10 patients with advanced non-diabetic chronic renal failure (S-creatinine 672 +/- 259 mumol l-1, mean +/- SD). Renal glomerular function measured as creatinine clearance and plasma clearance of [99Tcm]-diethyl-enetriaminepentaacetic acid (DTPA) was unchanged by iopentol, as also was urinary excretion of the renal tubular enzymes N-acetyl-beta-glucosaminidase (NAG) and alkaline phosphatase (ALP). The elimination of iopentol from serum and urine was delayed, and detectable serum and urine concentrations were found 5 days after administration of the contrast medium. Creatine clearance was 47% higher than the corresponding renal iopentol clearance. Plasma iopentol clearance, measured as the total area under the plasma concentration curve, was 40% higher than renal iopentol clearance because of extrarenal elimination of iopentol. We conclude that abdominal aortography with iopentol can be performed without effects on renal glomerular or tubular function parameters in patients with advanced renal failure. If iopentol is used for measurement of glomerular filtration rate (GFR) in this group of patients, one should measure renal clearance, as plasma clearance overestimates GFR.

CT and angiography in adrenocortical carcinoma

CT and angiography were performed in 15 patients with adrenocortical carcinoma. The tumors had a mean diameter of 11 cm (range 4-20 cm). At CT, the 8 largest tumors were ill-defined, and in these, the organ of tumor origin could not be established. Angiographically the correct organ of tumor origin was established in all but one patient. It is concluded that CT is excellent in showing the extent of an adrenal tumor, but is often unable to predict the organ of origin in large tumors. Angiography is still of great value in the preoperative work-up in patients with large adrenocortical carcinomas for correct identification of tumor origin and for vascular mapping.