Objectives

To illustrate the different surgical techniques performed in Bariatric surgery and the post-operative anatomy, highlighting the most common imaging findings and the main complications after these procedures.

Background

In 1997 the World Health Organization recognized obesity as a global epidemic. This condition is defined as having a Body Mass Index (BMI) greater or equal to 30kg/m².

Bariatric surgery has proven to be a treatment of choice for patient with a BMI>40 or a BMI>35 with comorbidities (i.e. type 2 Diabetes or Metabolic Syndrome).

In our University hospital, in the last 3 years, 950 patients underwent Bariatric surgery.

The mainstay surgical procedures are:

laparoscopic adjustable gastric banding (GB), used in 14% of cases;

laparoscopic sleeve gastrectomy (SG), used in 63% of cases;

laparoscopic roux-en-y gastric bypass, used in 23% of cases.

Imaging findings OR Procedure findings

The main imaging modalities used to assess post-operative developments are Computer-Tomography (CT) of the abdomen and fluoroscopic gastrointestinal examination with barium or Gastrografin.

We provide a detailed description of fluoroscopic and CT post-surgical anatomy and imaging findings of common and uncommon complications, e.g. GB displacement (4% of cases), staple leakage (0,7-7%), bleeding (0,9-3%), anastomotic leaks and strictures, perforation, internal hernia, gastro-bronchial and intra-abdominals fistulas (all accounting for less than 1% of cases).

Conclusion

A detailed knowledge of post-operative imaging findings and possible complications of Bariatric surgery is crucial for radiologists since the number of people recurring to these procedures is steadily increasing.

Purpose

To evaluate efficacy and safety of percutaneous microwave ablation (MWA) using simultaneous activation of two antennas for the treatment of liver malignant lesions.

Material and methods

25 MWA procedures of liver malignant lesions were performed: 5 (20%) HCC, 14 (56%) unresectable liver metastases and 6 (24%) recurrences of treated liver metastases. MWA was performed with simultaneous activation of two antennas with a spacing of 1.5 or 2.0. Microwave energy was applied for 10 min with a power of 65 W. The sizes of the ablative zones created were recorded. Technical success was defined as complete target devascularization at the immediate post-procedural CT. One, 3 and 6 months post-procedure follow-up was performed and major and minor complications were reported.

Results

Mean tumor size was 3.5cm (3-7cm). Full technical success was achieved in all treated liver malignant lesions. Mean short-axis diameter of the ablation zone was 6.0cm (4.8-9cm). All ablative zones were spherical or ellipsoid in both the axial and transverse planes with an antenna spacing of 2.0 cm or less. Artificial dissection was performed in one case (4.8%) due to diaphragm proximity. In three cases (14%) peri-procedural complications were observed: one subcapsular hemorrhage, one biloma and one peripheral portal thrombosis. Recurrence of disease was reported in three cases (14%) at 3 months follow-up. All recidivated lesions had a maximum size ≥5cm (5-7cm).

Conclusion

Our results provide preliminary evidence of efficacy, creating a larger necrotic area, and safety, for the low complication rate, of simultaneous MWA using multiple antennas for local control of liver malignant lesions.