Traumatic injury of the thoracic aorta treated with stent-graft: is long-term CT angiography follow-up justified?

AIM: To report the results of long-term (>5 years) computed tomography (CT) angiography follow-up after thoracic endovascular aortic repair in patients with traumatic thoracic aortic injury. MATERIALS AND METHODS: All follow-up CT angiographies performed in patients with traumatic thoracic aorta injury treated by endovascular stent-graft between 2002 and 2008 were reviewed. Of the 14 patients treated, seven patients had CT angiography follow-up examinations for more than 5 years. All patients were men with a mean age of 26 years. The Talent device was used in four patients and Gore TAG device in three patients. The mean device diameter and length were 24.6 mm and 103 mm, respectively. Follow-up included annual outpatient clinic surveillance and CT angiography examinations, which were reviewed for any device-related complications. The radiation effective dose was calculated from the CT dose report. RESULTS: Thirty-three CT examinations performed 64-110 months (mean 76) after stent-graft implementation were reviewed. The mean follow-up number of examinations per patient was 4.7 (range 2-8). Intra-graft circular mural tissue at the distal part of the stent-graft was seen in one patient. Stable lack of proximal device apposition was seen in all patients. No other radiological complications (e.g., aortic infection, dilatation, aneurysm or pseudoaneurysm, device struts breakage, migration, collapse, endoleak) were detected. None of the patients developed hypertension. The average effective dose was 77.01 mSv (range 34.11-128.84 mSv). CONCLUSION: CT angiography did not reveal any complications developing throughout the long-term follow-up. These results suggest that long-term CT angiography follow-up may not be required.

Appendicitis in adults with incidental midgut malrotation: CT findings.

AIM: To report the computed tomography (CT) findings of acute and complicated appendicitis in adults with incidental midgut malrotation. MATERIALS AND METHODS: The medical records and CT studies of eight patients with appendicitis and incidental midgut malrotation who presented to two medical centres between 1998 and 2009 were reviewed. RESULTS: All patients presented with 1-5 days of acute abdominal pain, which was diffuse in two, left-sided in two, lower abdominal in two, and in the right lower quadrant in two patients. The inflamed appendix was right-sided in three, left-sided in three, and in the midline in two patients. Three cases were complicated by a peri-appendicular abscess, and one patient also had a small bowel obstruction. All patients had a complete non-rotation with right-sided duodenum and jejunum, and left-sided colon. All eight patients had an abnormal superior mesenteric artery-superior mesenteric vein (SMA/SMV) relationship and a dysplastic uncinate process of the pancreas. Urgent surgery was performed in six patients and the remaining two were treated conservatively. CONCLUSION: Altered anatomy in malrotation affects the typical clinical and CT findings of acute appendicitis, therefore delaying diagnosis. When CT shows focal inflammation anywhere within the abdomen, along with an abnormal SMA/SMV relationship, the position of the caecum should be ascertained and acute appendicitis ruled out.

Dropped gallstones: spectrum of imaging findings, complications and diagnostic pitfalls.

Spillage of gallstones into the abdominal cavity, referred to as "dropped gallstones" (DGs), occurs commonly during laparoscopic cholecystectomy. The majority of these spilled stones remain clinically silent; however, if uncomplicated DGs are not correctly identified on subsequent imaging, they may mimic peritoneal implants and cause unduly concern. A small percentage of DGs cause complications, including abscess and fistula formation. Recognising the DG within the abscess is critical for definitive treatment. This pictorial review illustrates the imaging appearances and complications of DGs on CT, MRI and ultrasound and emphasises pitfalls in diagnosis.

Changes in spleen volume after resection of hepatic colorectal metastases.

AIM: To identify and describe changes in spleen volume occurring in patients with colorectal metastases to the liver after partial hepatectomy. MATERIALS AND METHODS: Forty-one consecutive patients (20 men, 21 women) with histopathology-proven colorectal liver metastases who underwent partial hepatectomy between August 2007 and April 2011 were included. Liver and spleen volumes were measured by computed tomography (CT) volumetry on the most recent CT prior to surgery and on all CTs obtained within a year after partial hepatectomy. Patients were carefully evaluated for and excluded if they had co-morbid conditions known to cause splenomegaly or risk factors for portal hypertension such as underlying liver disease and portal vein thrombosis. RESULTS: Thirty-two (78%) patients demonstrated an increase in spleen volume on the first post-operative CT, with more than a double increase in volume amongst five patients. Spleen volume increased by an average of 43% within 3 months of partial hepatectomy (p < 0.0001) and remained increased through 6 months after surgery, returning to near baseline thereafter. In the remaining nine (22%) patients, the spleen was observed to decrease an average of 11% in volume on first postoperative CT (p < 0.005). CONCLUSIONS: Splenic enlargement after partial hepatectomy of colorectal metastases is a common finding on CT. Increased familiarity amongst radiologists of this phenomenon as likely reflecting physiological changes is important in order to avoid unnecessary evaluation for underlying conditions causing interval enlargement of the spleen.

Enlargement of the spleen as an incidental finding on CT in post-partum females with fever.

OBJECTIVE: The aim was to evaluate whether enlargement of the spleen on CT in a post-partum female with fever is a common phenomenon. METHODS: In this retrospective institutional review board-approved study, the spleen was measured by CT in 77 females (average age 30.7 years) examined for post-partum fever and a control group of 58 febrile females imaged for suspected appendicitis (average age 29.7 years). The splenic length, width and thickness were measured and used to calculate the splenic index. The measurements of both groups of patients were compared. The size of the spleen was assessed again in 12 of the 77 post-partum female who had a follow-up CT for unrelated reasons. Continuous variables were compared, by groups, using analysis of variance (ANOVA). ANOVA with repeated measures was used to evaluate changes over time. A p-value <0.05 was considered significant. RESULTS: The length, thickness and width of the spleen were significantly larger in the patients imaged after delivery compared with those in the control group (p<0.001 for all three comparisons). The mean splenic index was 686.6 cm(3) in the post-partum group and 408.1 cm(3) in the control group (p<0.001). The splenic dimensions and index were significantly smaller in the 12 post-partum females who had a follow-up study. CONCLUSION: An enlarged spleen in febrile females undergoing CT in the puerperium may reflect physiological changes occurring during pregnancy.

CT diagnosis of a large peritoneal loose body: a case report and review of the literature.

We report a case of a large peritoneal loose body (LPLB), diagnosed on CT. The loose body appeared as a round pelvic mass with central calcifications and a distinct fat plane separating it from adjacent organs. The mass changed its location from the left to the right side of the pelvis within 9 days on repeat imaging. The typical cross-sectional characteristics of a LPLB include a mobile well-circumscribed soft-tissue mass usually with coarse central calcifications. The accurate diagnosis of a LPLB is vital to prevent unnecessary surgical intervention in an asymptomatic patient with an incidentally discovered LPLB.

Sealed rupture of abdominal aortic aneurysms: CT features in 6 patients and a review of the literature.

PURPOSE: To assess the CT features of sealed rupture of abdominal aortic aneurysm. PATIENTS AND METHODS: We reviewed the CT scans of six index cases obtained over a 3 year period with a sealed rupture of an abdominal aortic aneurysm and those reported in the literature over a 21 year period. CT scans were reviewed for aneurysm size, the presence of a draped aorta and adjacent vertebral erosion. A group of consecutive patients with non-ruptured abdominal aortic aneurysm, referred for endovascular aneurysm repair during the same 3 year period constituted the control group. RESULTS: In the study group of 31 patients the mean size of the aneurysm was 6.24 +/- 2.01 cm, compared to 6.01 +/- 0.99 cm in the control group, without statistically significant difference (t = 0.75, df = 97, P = 0.46). A draped aorta was detected in all patients with a sealed rupture. Vertebral erosion was present in all our six, but mentioned in only 14 of the cases reported. CONCLUSION: A sealed rupture of an abdominal aortic aneurysm can occur in relatively small aneurysms. A draped aorta and adjacent vertebral erosion are characteristic CT signs of such a rupture.

Abdominal CT findings in small bowel perforation.

Small bowel perforation is an emergent medical condition for which the diagnosis is usually not made clinically but by CT, a common imaging modality used for the diagnosis of acute abdomen. Direct CT features that suggest perforation include extraluminal air and oral contrast, which are often associated with secondary CT signs of bowel pathology. This pictorial review illustrates the CT findings of small bowel perforation caused by various clinical entities.

Pseudoaneurysm of the renal artery following partial nephrectomy: imaging findings and coil embolization.

AIM: To present the imaging findings of five patients with renal artery pseudoaneurysm (RAP) after partial nephrectomy. METHODS: Five patients (four men and one woman) with RAP as a complication of partial nephrectomy were studied. The diagnosis of RAP was established using contrast-enhanced computed tomography (CT) in three patients and renal angiography in two patients. In two cases, the diagnosis was evident on ultrasound with colour Doppler. RESULTS: The indication for partial nephrectomy (open approach in four patients and laparoscopic in one patient) was a space-occupying lesion, which proved to be a renal cell carcinoma. All patients presented with macroscopic haematuria, 1-21 days (mean 12.2 days) after surgery. In three of patients the definitive diagnostic imaging method was contrast-enhanced CT. The arterial phase of CT showed a well-circumscribed dense collection of contrast material located within the renal parenchyma. In two other patients the initial and conclusive diagnostic imaging method was renal angiography. All patients underwent selective renal angiography with therapeutic coil embolization. The procedure failed in one patient, which necessitated nephrectomy. CONCLUSIONS: Pseudoaneurysm of the renal artery should be considered in patients presenting with macrohaematuria after nephron-sparing surgery. The diagnosis can be established using contrast-enhanced CT, ultrasound with colour Doppler, or angiography. Renal angiography with selective embolization is a safe and efficacious technique for managing the condition.

Transcatheter arterial embolisation in anticoagulant-related haematoma--a current therapeutic option: a report of four patients and review of the literature.

The aim of this study is to present the computed tomography (CT) and angiographic findings of life-threatening extraperitoneal haemorrhage complicating anticoagulant therapy, treated with transcatheter arterial embolisation (TAE). CT and angiographic studies of four consecutive patients with large, extraperitoneal anticoagulant-related haematomas (ACH) treated by TAE were retrospectively reviewed. Attention was directed to the location of the haematoma and to the possible presence of active arterial extravasation on CT. Four women (mean age 70 years) with large extraperitoneal ACH's demonstrated on CT as extended rectus sheath haematoma in three and expanding iliopsoas haematoma in one, were successfully treated by TAE of the inferior epigastric (n=3) and lumbar artery (n=1). Two patients were diagnosed by contrast-enhanced CT as having active arterial bleeding within the haematoma requiring TAE. The other two were referred to angiography because of haemodynamic instability. We also reviewed the imaging findings of 26 patients with extraperitoneal ACH's requiring TAE described in the literature. In the reviewed cases, a female predominance was found, the retroperitoneum was the most frequent site and most patients recovered. To conclude, unenhanced CT has proved an excellent modality for the diagnosis of ACH's. TAE has been shown to be an effective and safe method for managing such haematomas when conservative treatment is insufficient. We suggest that whenever a large extraperitoneal ACH is seen on unenhanced CT, a subsequent contrast-enhanced dynamic scan should be performed, unless contraindicated. Enhanced CT has a supplementary role in detecting active bleeding that provides an indication for angiographic therapy. Awareness of this optional treatment improve patient's outcome.

Rebound thymic enlargement on CT in adults.

The objective of this study is to report the development of thymic enlargement in adults, mainly associated with chemotherapy for malignancy. The typical CT features of this phenomenon are described. The clinical data and CT studies of 13 adult patients with newly appearing thymic enlargement on CT were reviewed. These patients were followed-up mainly for malignancy. Further follow-up CTs were studied when available. Medical records were reviewed as to the primary disease, its medical treatment and the time of initial appearance of the enlarged thymus in relation to treatment. The study group included 13 adult patients, 12 with malignant disease and one with a slowly resolving pneumonia. The enlarged thymus appeared as a triangular, arrowhead-shaped structure, with a bilobed configuration and convex borders. Density measurements were consistent with homogeneous soft tissue. Location was in the anterior mediastinum, in the normal site of the thymus. In nine patients, follow-up studies were available. The observation period ranged from 5 months to 8 years from the initial appearance of the enlarged thymus. In five of the nine patients, the thymic enlargement resolved after 1-4.5 years. In four of the nine patients, the thymus remained enlarged during a follow-up ranging from 5 months to 2.5 years. Thymic enlargement, while a rare phenomenon in adults, may occur, mainly after chemotherapy. This phenomenon should be included in the differential diagnosis of a soft tissue mass appearing in the anterior mediastinum on follow-up CT in adult patients particularly following treatment for malignancy.

The wandering spleen: CT findings and possible pitfalls in diagnosis.

AIM: To report the CT features of wandering spleen, a rare condition which can be incidentally detected as an abdominal or pelvic mass or can present with torsion, causing an acute abdomen. MATERIALS AND METHODS: The CT studies of seven patients, two children and five adults, with wandering spleen were reviewed. CT was performed urgently in three patients for acute abdomen, and electively in four. RESULTS: CT findings of wandering spleen included absence of the spleen in its normal position and a mass located elsewhere in the abdomen or pelvis, i.e. an ectopic spleen, enhancing homogeneously in four cases and failing partially or completely to enhance in the other three, indicating infarction. A "whirl" appearance representing the twisted splenic pedicle was seen in the three cases with torsion. Urgent splenectomy confirmed infarction secondary to torsion. CONCLUSION: The possible diagnosis of wandering spleen should be kept in mind when CT shows the spleen to be absent from its usual position and a mass is found elsewhere in the abdomen or pelvis. When, in addition, a "whirl" or partial or no enhancement of this mass are seen in a case presenting with acute abdomen, torsion of a wandering spleen is a likely diagnosis.

Congenital anomalies of the spleen.

Various congenital anomalies may affect the spleen, starting with common anomalies, such as an accessory spleen, up to rare conditions such as a wandering spleen and polysplenia. Most of these anatomic variants have no clinical significance; they need, however, to be recognized by the radiologist as such. Awareness of these variants is important for the radiologist to interpret the findings correctly and avoid mistaking them for a clinically significant abnormality. In this review we illustrate the spectrum of congenital anomalies of the spleen and stress pitfalls and possible complications resulting from these anomalies.

The CT findings of abdominal anticoagulant-related hematomas.

Spontaneous bleeding is a serious complication of anticoagulation that should be promptly recognized and treated. The clinical manifestations vary and are related to the site of the hemorrhage. CT, a simple and safe imaging modality, plays an important role in the accurate determination of the presence or absence of an anticoagulant-related bleed, its extent, and its precise location. This pictorial article reviews and demonstrates the CT findings of a variety of anticoagulant-related hematomas at various anatomical locations in the abdomen.

CT findings of latrogenic complications following gastrointestinal endoluminal procedures.

Abdominal CT, a simple and safe imaging modality, plays an important role in evaluating patients suspected of having abdominal complications following nonsurgical gastrointestinal procedures, to accurately determine the presence or absence of such insults. This pictorial article reviews and demonstrates the CT findings of various complications following upper endoscopy, percutaneous endoscopic gastrostomy, endoscopic retrograde cholangiopancreatography, endoscopic US, colonoscopy, and enemas (barium as well as cleansing).

Minimally invasive management of urolithiasis.

The management of urolithiasis has radically changed over the last two decades. Open surgery has been almost completely replaced by minimally invasive procedures, mainly extracorporeal shock wave lithotripsy (ESWL) and ureteroscopy (URS). Although these treatment modalities have been proven to be very safe and effective, serious complications can occur. Prompt diagnosis is often essential and may even be lifesaving. Radiologists play an important role in this setting, since many of these complications can be readily diagnosed by imaging. Awareness of the wide spectrum of complications may be crucial in interpreting imaging studies of patients who have undergone one of these procedures. This article reviews the contemporary management of ureteric stones with ESWL and URS and illustrates the radiological findings of complications of these procedures.

Fallopian tube carcinoma presenting as tubo-ovarian abscess: a report of two cases with literature review.

Preoperative diagnosis of fallopian tube carcinoma is difficult, with fewer than 5% being diagnosed preoperatively. We describe tubal carcinoma, presenting as a tubo-ovarian abscess in two 47-year-old women. Both patients presented with abdominal pain, pelvic mass, and fever. Both patients were treated as having a tubo-ovarian abscess but failed to respond to therapy. During surgery a metastatic right tubal carcinoma was found. A definite operation was performed in both patients. Three additional cases of fallopian tube carcinoma, presenting as acute pelvic inflammatory disease, were found while reviewing the English literature. Actually all these three cases presented as tubo-ovarian abscess because of the existence of tender pelvic mass. Carcinoma of the fallopian tube should be considered in the differential diagnosis of tubo-ovarian abscess in those who failed to respond to a previously unreported clinical presentation.

Congenital internal hernia as a cause of small bowel obstruction: CT findings in 11 adult patients.

The aim of this study is to report the CT findings in patients proved to have congenital internal hernia (CIH) as a cause of small bowel obstruction (SBO). The CT scans of 11 patients (9 men and 2 women, with ages ranging from 20 years to 95 years (mean 60.7 years), presenting with clinical symptoms and signs of SBO without previous abdominal surgery or trauma, were retrospectively reviewed. In all patients features of SBO were seen. In addition, in nine of them a saclike mass, containing dilated small bowel loops with mesenteric vessels converging toward its orifice was demonstrated and a pre-operative diagnosis of an incarcerated internal hernia was suggested. In the other two, a closed loop obstruction was seen without an identifiable cause. Mural thickening of the entrapped loops within the hernial sac was seen in five patients, with hypoperfusion in four of them, blurring of the mesenteric vessels with localized mesenteric fluid was demonstrated in seven and free peritoneal fluid in 10. All patients were operated on following the CT and an incarcerated CIH was confirmed. Gangrenous bowel was present at exploration in seven cases. One patient died. In conclusion, in patients with intact abdomen and SBO, CT may be the first imaging modality to discover a clinically unsuspected CIH, which requires prompt surgical intervention. Radiologists should be aware of the CT features suggestive of a SBO caused by CIH, i.e. a saclike mass of dilated small bowel loops, as a correct diagnosis will influence patient management and prognosis.