Follow-up and final results of the Oslo I Study comparing screen-film mammography and full-field digital mammography with soft-copy reading.

PURPOSE: To compare cancer detection rates of screen-film (SFM) and full-field digital mammography (FFDM) with soft-copy reading in a screening program including the initial positive scores for interval cancers and cancers in the subsequent screening round, and to analyze the false-negative FFDM interpretations. MATERIAL AND METHODS: Using a paired study design, 3683 women underwent SFM and FFDM in a population-based screening program. Two standard views of each breast were acquired. The images were interpreted without previous films for comparison. Independent double reading using a 5-point rating scale for probability of cancer was used for each modality. An examination was defined as positive if at least one of the two independent readers scored 2 or higher on the 5-point rating scale. SFM-positive cases were discussed in a SFM consensus meeting and FFDM-positive cases in a separate FFDM consensus meeting before recall. The study population was followed for more than 2 years so that interval cancers and screen-detected cancers in the subsequent screening round could be included. Cancer detection rates were compared using the McNemar test for paired proportions. The kappa statistic and Wilcoxon signed-rank test for matched pairs were used for comparing rating scores. The reading time was recorded for all FFDM interpretations. RESULTS: A total of 31 cancers (detection rate 0.84%) were diagnosed initially, of which SFM detected 28 and FFDM 23 (McNemar test P=0.23, discordant pair 8 and 3). Two cancers with a positive score at initial SFM reading and three with a positive score at initial FFDM reading were dismissed at SFM and FFDM consensus meetings, respectively. The difference in cancer detection after recall (discordant pair 11 and 5) was not significant (McNemar test, P=0.21). Of the 10 interval cancers and 16 screen-detected cancers in the subsequent round, 3 had true-positive SFM scores while 4 had true-positive FFDM scores in the initial reading session. A total of 38 cancers therefore had a positive result at double reading at one or both modalities, 31 at SFM and 27 at FFDM (McNemar test, P=0.48). Comparison of SFM and FFDM interpretations using the mean score for each case revealed no statistically significant difference between the two modalities (Wilcoxon signed-rank test for matched pairs; P-value=0.228). Two initial round cancers (one tumor found incidentally at work-up for a mass proved to be a simple cyst with a positive score at FFDM but a negative score at SFM, and one tumor with positive score at SFM but negative score at FFDM due to positioning failure) were excluded from the further analysis. Excluding these two cancers from comparison, there were 31% (22 of 72) false-negative SFM and 47% (34 of 72) false-negative FFDM individual interpretations. The overall mean interpretation time for normal FFDM examinations was 45 s. For most false-negative FFDM results, the reading time was shorter or longer than for normal examinations. The recorded FFDM interpretation time was noticeably short for several overlooked cancers manifesting as microcalcifications (ductal carcinoma in situ). CONCLUSION: There is no statistically significant difference in cancer detection rate between SFM and FFDM with soft-copy reading in a mammography screening program. Analysis of cancers missed at FFDM with soft-copy reading indicates that close attention has to be paid to systematic use of image display protocols.

Interobserver variation in the interpretation of breast imaging. Comparison of mammography, ultrasonography, and both combined in the interpretation of palpable noncalcified breast masses.

PURPOSE: To analyze interobserver agreement in the interpretation of palpable noncalcified breast masses by means of mammography, ultrasonography, and a combination of both methods. MATERIAL AND METHODS: Mammograms and ultrasonograms of 100 benign breast masses and 100 malignant ones in 200 patients were retrospectively analyzed by 4 radiologists with experience in both imaging modalities. The images were analyzed independently and without knowledge of the final diagnosis. The analysis was performed in 3 sessions and used a 5-point rating scale for probability of malignancy. The interobserver variation was analyzed by means of observed agreement, kappa, and weighted kappa statistics based on the 5-point rating scale and a 3-level scale of the collapsed 5-point scale. The chi-square statistic was used for testing the equality of the kappa values. RESULTS: The overall kappa value on the 3-level scale was 0.48 (range 0.37-0.61) for ultrasonography, 0.58 (range 0.52-0.66) for mammography, and 0.71 (range 0.63-0.79) for the combined reading. The kappa values were statistically different for ultrasonography but did not differ significantly for the mammographic and combined readings. The combined reading showed higher kappa values than mammography alone, and the improvement was statistically significant for 3 of the 6 pairs of comparison. CONCLUSION: Radiologists differ substantially in their interpretations of mammograms and breast ultrasonograms. Agreement was highest in the combined reading, intermediate in mammography, and lowest in ultrasonography.

[Percutaneous transluminal angioplasty in the treatment of arteriosclerosis of the lower extremities]. / Perkutan transluminal angioplastikk ved behandling av arteriosklerose i underekstremitetene.

With the introduction of balloon catheters in 1974, dilatation of arteriosclerotic stenoses has become an important treatment for this condition. During the years 1979-88, 368 such procedures were performed in 270 patients. Two patients (0.7%) died from complications. In 8%, revascularisation was unsuccessful. Long occlusions appeared especially difficult to recanalize. 81% of the patients were improved by the treatment. The long term results were best in the iliac segment with 5-year patency of 90% after dilatation of short stenoses (< 4 cm) and 65% after dilatation of longer stenoses. In the femoropopliteal segment, the 5-year patency rates were 65% and 50% respectively. Results after recanalisation of occlusions were poor. Percutaneous transluminal angioplasty is an important supplement to surgery, applying mainly to patients with limited arteriosclerosis and moderate symptoms.

[Percutaneous pleural and pericardial drainage]. / Perkutan pleura-og perikarddrenasje.

Both MRI, CT and sonography will give a good presentation of fluid collection in pleura and pericardium. Sonography is the ideal imaging method for monitoring interventional procedures. Its ability to visualize superficial fluid collection and its real-time capability allows precise control of needle and catheter insertions. If the abnormality is poorly seen with ultrasound, often because of air in the collection, CT can be used as a guidance system. Diagnostic thoracocentesis and pericardiocentesis are performed mainly to exclude malignancy and infections, and the punctions are made with small needles. Therapeutic thoracocentesis is usually performed to relieve dyspnoea and small catheters are used. Drainage of empyema is performed with larger catheters because of the high viscosity of the infected fluid. Patients with threatening cardiac tamponade will often respond immediately to drainage of the pericardial space by catheter. These procedures can be done with local anesthesia only. If complications occur, it is mainly the pneumothorax that has to be treated. This can be managed directly under the procedure as the drainage catheter is attached to continuous pleural suction, or a catheter can be inserted in the pleural space after diagnostic punction. Patients with coagulation abnormalities must be evaluated especially before any intervention, otherwise there are no contraindications for these image-guided percutaneous procedures.

[Percutaneous drainage of abdominal abscesses]. / Perkutan drenasje av abdominale abscesser.

Percutaneous drainage of abdominal abscesses has proved to be one of the most successful and gratifying of all interventional radiology procedures. Collections of intra-abdominal fluid can be detected easily with computer tomography and sonography. Diagnostic aspiration is done under guidance of sonography or computer tomography. Sonography is the ideal imaging method for monitoring interventional procedures. Its ability to visualize the collection of superficial fluid and its real-time capability allows precise control of insertions of needles and catheters. If the collection is poorly seen with sonography, often because of air, computer tomography can be used as a system of guidance. It is essential that radiologists and surgeons collaborate in the treatment of patients with abscesses. Percutaneous drainage is favoured in patients at high risk with open surgery, while diffuse collections between bowels almost always need surgical drainage. Simple abscesses can be treated successfully with percutaneous drainage. Complicated abscesses in the pancreas can also be treated with good results. The procedure is carried out under local anaesthesia. Most complications are minor and can be treated conservatively. Coagulation abnormalities must be corrected, but there are no other contraindications to these image-guided percutaneous procedures.

Value of computed tomography in preoperative evaluation of resectability and staging in oesophageal carcinoma.

OBJECTIVE: To evaluate computed tomography (CT) as a method of staging patients with oesophageal carcinoma. DESIGN: Retrospective study. SETTING: Ullevaal Hospital, Oslo, Norway. SUBJECTS: 85 patients who presented with oesophageal carcinoma between February 1982 and December 1989. INTERVENTIONS: Assessment by CT was made in all patients. MAIN OUTCOME MEASURES: Correlation with findings at operation, and histological examination of operative specimens. RESULTS: From the findings at operation in the 46 patients who were operated on (resection, n = 39; exploration only, n = 7) the sensitivity, specificity, and accuracy of CT staging of the growth were 80%, 91%, and 88%, and when histological confirmation of infiltration was taken into consideration the figures were 25%, 84%, and 54%, respectively. The sensitivity, specificity, and accuracy of CT detection of lymph node metastases were 22%, 95%, and 55%. CONCLUSION: Staging of oesophageal cancer with CT before operation is useful in judging resectability, but the smaller tumours should be assessed with caution. CT is unreliable in the diagnosis of the depth of infiltration and the presence of lymph node metastases compared with histological examination.

[Computer tomography after reconstructive vascular surgery of the abdominal aorta. Can fluid around the aortic prosthesis be considered a normal finding?]. / Computertomografi etter rekonstruktiv karkirurgi på aorta abdominalis. Kan vaeske rundt aortaprotese vaere et "normalt" funn?

15 patients who had elective aortic reconstruction for infra-renal aortic aneurysm (nine patients) or aortoiliac occlusive disease (six patients) were evaluated using postoperative computerized tomography. The assessment was performed 1-2 weeks, 6-8 weeks and 6-8 months after implantation of woven Dacron graft. All patients were without clinical or laboratory signs of infection. The presence or absence of retroperitoneal air or fluid collections was assessed. In patients operated on for aneurysms, perigraft fluid was present in two cases 6-8 weeks after operation, but had disappeared within 6-8 months. Even after only 1-2 weeks, no accumulation of periprosthetic fluid was found in patients operated on for occlusive disease. Retroperitoneal air was not seen in any of the cases. It is concluded that perigraft fluid may be a "normal" phenomenon during the early postoperative period in patients operated on for abdominal aortic aneurysm.

[Severe hemorrhage in pancreatic pseudocyst]. / Alvorlig blødning ved pancreascyste.

Pseudocysts in the pancreas occur in 10% of patients with pancreatitis and may lead to serious complications, i.e. infection, obstruction of the bile duct, rupture, and hemorrhage. The last complication is highly lethal. Two patients are described, with differing modes of presentation and therapy. In one patient hemostasis was obtained by surgical packing followed by percutaneous embolization. In the other patient embolization failed and surgical resection was necessary.

Rupture of a splenic artery aneurysm into the pancreatic duct. Case report.

A 71-year-old woman was admitted to a local hospital with abdominal pain and repeated haematemeses and melaena. Plain X-ray of the abdomen showed a cystic mass with a calcified wall behind the stomach. No bleeding point in the stomach or duodenum was found at gastroscopy. Over a period of 28 days she had five episodes of gastrointestinal haemorrhage with no drop in blood pressure. She was transferred to the regional hospital 26 days after admission. Angiography showed a splenic artery aneurysm 5 x 10 cm, which at operation was found to have ruptured into the pancreatic duct. The aneurysm, the tail of the pancreas and the spleen were removed, and she made an uneventful recovery.

[Surgical treatment of necrotizing fasciitis]. / Kirurgisk behandling ved nekrotiserende fasciitis.

We present nine patients with necrotizing fasciitis. Two of them had Fourniers gangrene. Predisposing factors included diabetes mellitus, alcohol and drug abuse. Local signs were redness, swelling and pain rapidly followed by fever and deterioration in the patient's general condition. Soft tissue-gas was observed in all patients. It was found either clinically, on roentgenograms or by CT. Bacteria were found in blood cultures and/or necrotic tissues in all patients. The dominating treatment was radical surgical excision and early reexplorations. Antibiotics, intensive care support and early parenteral nutrition were given. Four patients were given hyperbaric oxygen treatment. The overall mortality rate was 11%. Amputation of one lower extremity became necessary in three patients. In these cases 4-8 days had elapsed between the onset and the first surgical excision. We find it important to underline early diagnosis and radical surgical excision in patients with necrotizing fasciitis.

Transhepatic endoprosthesis and surgical anastomosis in the palliative treatment of bile duct obstructions.

Ninety-six patients with non-resectable malignant tumours occluding the bile duct were treated either with a transhepatic endoprosthesis (n = 60) or a surgical biliointestinal anastomosis (n = 36). The mean survival time for patients treated with a transhepatic endoprosthesis was 5.8 months, as compared with 8,1 months for patients treated surgically. The mortality rates in the first 30 days were 18% and 17% for patients treated anastomosis, respectively. We consider that this militates in favour of an endoprosthesis rather than surgery.

Out-patient surgical biopsy for nonpalpable breast lesions. Technique, results and consequences.

During the last 5 years wire-marked biopsies of nonpalpable mammary lesions have been performed with use of local anesthesia in our out-patient department. The diagnostic accuracy and the complication rate were comparable with those reported from biopsies in general anesthesia. The patients tolerated the procedure well. A malignant: benign diagnostic ratio of 1:2.7 was obtained by close collaboration between the participating surgeons, radiologists and pathologists.

Treatment of biliary fistula by percutaneous transhepatic drainage. Case report.

Percutaneous transhepatic biliary drainage was performed in two patients with bile-duct injury resulting from surgery. A fistula healed without surgical intervention in both cases. This type of drainage seems to be therapeutically suitable for selected cases of iatrogenic bile duct lesion.