Imaging in bariatric surgery: a guide to postsurgical anatomy and common complications

OBJECTIVE: This article reviews the various bariatric surgical techniques and the associated imaging findings of normal postoperative anatomy and of common complications. CONCLUSION: Bariatric surgery is increasingly performed to control morbid obesity secondary to failed medical approaches. As a result, imaging plays an important role in postoperative evaluation and management. Practical knowledge of postsurgical anatomy allows accurate interpretation of imaging findings related to normal postsurgical anatomy and common postsurgical complications.     

Postoperatives Syndrom nach Wirbelsäuleneingriffen

Postoperative syndrome after spine surgery, i.e., symptoms or syndromes caused by complications or procedure-related consequences, is gaining more and more importance. Due to great improvements concerning imaging and operative techniques (microsurgery, instrumentation) the total number of spinal surgeries as well as their related complications are increasing. Procedure-related postoperative complications including neurological deficit syndromes can occur acutely or at a later date. Concerning imaging techniques for postoperative evaluation after spinal surgery there are several modalities available. Their indications depend on complex factors including initial pathology the surgery was performed for, kind of surgical technique (surgical approach, instrumentation), anatomy of the patient as well as the time between onset of symptoms and surgery. In cases of ambiguous findings, the combination of different imaging techniques can be instrumental.     

CT and MRI features of ileostomies

OBJECTIVE: The purpose of this article is to describe CT and MRI features of normal anatomy, variants, and pathologic conditions of different ileostomies. CONCLUSION: Multiplanar imaging techniques are useful to identify the complications related to stoma construction and preexisting disease. Understanding the indications for ileostomy construction, surgical techniques, and postoperative anatomy is important for differentiating normal and abnormal imaging features.     

Renal Transplant Complications: Diagnostic and Therapeutic Role of Radiology

Kidney was the first and is the most frequently transplanted organ. Despite improved surgical techniques and transplantation technology, complications do occur and, if left untreated, may lead to catastrophic consequences. Renal transplantation complications may be vascular (eg, renal artery and vein stenosis and thrombosis, arteriovenous fistula, and pseudoaneurysms); urologic (eg, urinary obstruction and leak, and peritransplantation fluid collections, including hematoma, seroma, lymphocele, and abscess formation); and nephrogenic, including acute tubular necrosis, graft rejection, chronic allograft nephropathy, and neoplasm. Early diagnosis and treatment of these complications are paramount to prevent graft failure and other significant morbidities to the patients. Radiology plays a pivotal role in the diagnosis and treatment of these complications, with minimally invasive percutaneous techniques. In this article, we reviewed renal transplantation anatomy, a wide range of complications that may occur after renal transplantation surgery, typical imaging appearances of the complications on varies imaging modalities, and percutaneous interventional techniques that are used in their treatment.     

Imaging of the various continent urinary diversions after cystectomy

Continent urinary diversions have recently become the preferred procedures rather than performing an ileal conduit. Intravenous urography, pouchography, and computed tomography scans are frequently used for postoperative evaluation of patients with bladder carcinoma. During postoperative follow-up imaging studies, the radiologist must keep these 4 facets in mind as his primary focus: 1) the detection of newly developed urothelial tumors, 2) the detection of metastasis, 3) the detection of postoperative complications, and 4) the monitoring of upper urinary tract distention. Various surgical techniques that are used in continent diversions alter the normal anatomy and make the imaging interpretation difficult. An accurate interpretation can be made only if radiologists become familiar with the various surgical procedures and the appearances of various postoperative anatomic changes.     

The ostiomeatal unit and endoscopic surgery: anatomy, variations, and imaging findings in inflammatory diseases.

Recent and ongoing advances made in endoscopic surgical techniques require the radiologist to understand the anatomy and pathophysiology of the paranasal sinuses and nasal passage. Endoscopy and CT are complementary procedures, and, as such, the normal anatomic relationships and their CT appearances need to be well understood in order for radiologists to offer continued support as consultants to their clinical colleagues. In this article, we review the pertinent anatomy of the lateral nasal wall and paranasal sinuses, discuss the most frequently encountered normal variations that may predispose a patient to inflammatory sinus disease, outline imaging protocols for evaluation of this region, and introduce the reader to current endoscopic surgical techniques. Last, the imaging findings in various inflammatory processes involving the sinuses, as well as the local and regional complications associated with paranasal sinus inflammatory diseases, are presented.     

Postoperative Bildgebung der Schulter

Correct interpretation of imaging findings in the postoperative shoulder is impaired by surgical distortion of normal anatomy and possible artifacts. Advanced postoperative imaging of the shoulder in addition to the selection of the best suited modality necessitates familiarity with the surgical procedure that has been performed and its consecutive morphological changes. This article reviews the most common arthroscopic and open techniques used for treatment of shoulder instability, lesions of the superior labral-bicipital complex, primary impingement, and rotator cuff tears, their typical postoperative imaging findings, as well as the diagnostic performance of cross sectional imaging techniques in the detection of recurrent lesions and complications.     

Imaging the pediatric prostate

The prostate gland is not often the target of imaging in children but may be imaged during investigation of symptoms related to the lower genitourinary tract such as hematuria, urinary retention, dysuria, and incontinence or during an evaluation for suspected congenital anomalies. Ultrasound and voiding cystourethrography are useful for initial evaluation of congenital and neoplastic disorders of the prostate. MR imaging and CT are useful in delineating more detailed anatomy before surgical planning and in determining the organ of origin in a patient who has a large pelvic mass.     

Imaging of urinary tract infection in the adult

The diagnosis of urinary tract infection (UTI) in the adult is primarily based on typical patient symptomatology and urinary evaluation for the presence of bacteria and white blood cells. Uncomplicated UTI usually does not require radiological evaluation unless it is recurrent. Imaging should, in general, be reserved for those patients in whom conventional treatment has failed or those who have recurrent or unusually severe symptoms. Patients with conditions predisposing to infection, or complications thereof, such as diabetes mellitus or immunocompromised states, may also benefit from early imaging. If pyonephrosis is suspected, early imaging and possible urgent drainage is also warranted. Intravenous urogram and ultrasound have traditionally been used in the assessment of these patients, allowing detection of calculi, obstruction and incomplete bladder emptying. These imaging techniques, while useful, have limitations in the evaluation of renal inflammation and infection in the adult. Computerised tomography has now become accepted as a more sensitive modality for diagnosis and follow-up of complicated renal tract infection. Contrast-enhanced CT allows different phases of excretion to be studied and can define extent of disease and identify significant complications or obstruction. Nuclear medicine has a limited role in the evaluation of urinary tract infection in adults. Its main role is in the assessment of renal function, often prior to surgery. Magnetic resonance imaging has a limited but increasing role. It is particularly useful in those with iodinated contrast allergies, offering an ionising radiation free alternative in the diagnosis of both medical and surgical diseases of the kidney.     

Imaging of urinary tract infection in the adult

The diagnosis of urinary tract infection (UTI) in the adult is primarily based on typical patient symptomatology and urinary evaluation for the presence of bacteria and white blood cells. Uncomplicated UTI usually does not require radiological evaluation unless it is recurrent. Imaging should, in general, be reserved for those patients in whom conventional treatment has failed or those who have recurrent or unusually severe symptoms. Patients with conditions predisposing to infection, or complications thereof, such as diabetes mellitus or immunocompromised states, may also benefit from early imaging. If pyonephrosis is suspected, early imaging and possible urgent drainage is also warranted. Intravenous urogram and ultrasound have traditionally been used in the assessment of these patients, allowing detection of calculi, obstruction and incomplete bladder emptying. These imaging techniques, while useful, have limitations in the evaluation of renal inflammation and infection in the adult. Computerised tomography has now become accepted as a more sensitive modality for diagnosis and follow-up of complicated renal tract infection. Contrast-enhanced CT allows different phases of excretion to be studied and can define extent of disease and identify significant complications or obstruction. Nuclear medicine has a limited role in the evaluation of urinary tract infection in adults. Its main role is in the assessment of renal function, often prior to surgery. Magnetic resonance imaging has a limited but increasing role. It is particularly useful in those with iodinated contrast allergies, offering an ionising radiation free alternative in the diagnosis of both medical and surgical diseases of the kidney.     

Imaging of the postsurgical small bowel

The small bowel is subject to a variety of surgical interventions for the treatment of a broad spectrum of disease processes. Most operative procedures applied to the small bowel are straightforward techniques encumbered by few complications, whereas other procedures are considerably more complex and can be associated with significant postoperative morbidity. Familiarity with the anatomic alterations related to the various operations is essential, both for evaluation of early postoperative complications and those abnormalities that manifest late in the postoperative course. The surgeon and radiologist should carefully coordinate clinical suspicion with the strengths of the various imaging modalities to optimize postsurgical assessment and provide timely and accurate diagnosis. Enteric anastomoses, the different forms of enterostomy, and the varied constructions of small bowel pouches and reservoirs are each associated with unique anatomy and therefore optimal techniques of assessment. Small bowel contrast studies such as enteroclysis--including its recent modification, CT enteroclysis--and CT imaging represent the primary modalities for imaging of the postoperative bowel and its related abnormalities. Small bowel transplantation continues to progress as a realistic treatment for intestinal failure, and the role of diagnostic imaging in these unique and challenging patients is evolving.     

Kock continent ileal urinary reservoir. Anatomy and potential pitfalls of radionuclide imaging

The Kock continent ileal urinary reservoir (Kock pouch) is a new form of urinary diversion that, due to its advantages over previous techniques of urinary bypass, will probably become widespread in urologic practice. When bone imaging is performed in the presence of the Kock pouch, the unusual configuration of the pouch may obscure or simulate osseous lesions. An understanding of the surgical anatomy as well as the planar and SPECT scintigraphic appearances of the Kock pouch is necessary to avoid errors during interpretation. This series of 51 bone images reports on the variable scintigraphic appearance of the Kock pouch. In addition, the incidence and type of potentially avoidable pitfalls in the interpretation of bone imaging when this form of urinary diversion is used are evaluated.     

CT scanning of middle ear cholesteatoma: what does the surgeon want to know?

The history of surgery for middle ear cholesteatoma is of an evolution of techniques to meet the challenges of inaccessible disease and of post-operative cavity management. The concept has traditionally been of exploration guided by awareness and anticipation of all, possibly asymptomatic, complications. Modern imaging reliably demonstrates surgical anatomy, dictating the ideal approach, forewarns of complications and may reveal the extent of disease. An apparent resistance amongst otologists to universal CT scanning prior to mastoidectomy contrasts with the enthusiasm of skull base surgeons or rhinologists for appropriate imaging.     

Postoperative MRI of the shoulder

Magnetic resonance imaging (MRI) evaluation of the postoperative shoulder presents technical and diagnostic challenges related to imaging artifacts from hardware and micrometallic shavings, postsurgical scarring, and morphological alterations. Improved visualization of postoperative shoulder anatomy and pathology can be obtained with the use of metal artifact reduction techniques as well as MR arthrography. In this article we review the MR techniques that are designed to address these technical and diagnostic challenges, and we discuss the definitions and indications, normal MRI appearance, and complications of routine surgical procedures for treatment of injuries to the rotator cuff, labral ligamentous complex, and biceps tendon. J. Magn. Reson. Imaging 2014;40:1280–1297 . © 2014 Wiley Periodicals, Inc .     

Coronary artery bypass graft imaging with 256-slice MDCT: surgical concepts,current techniques,and interpretation

Multidetector computed tomography (MDCT) scanners with current equipment allow for a rapid and robust noninvasive assessment of coronary artery bypass graft (CABG) anatomy and patency. With both appropriate expertise in MDCT techniques and knowledge in CABG imaging interpretation, radiologists should play an important and active role in the postoperative care of patients with bypass grafts. In this pictorial essay, we review the MDCT techniques and anatomy relevant to CABG imaging, interpretation pitfalls, some basic and advanced surgical designs, as well as postoperative graft complications in patients with CABG, with clinical illustrations from our local experience.     

Mini-Gastric Bypass to Control Morbid Obesity and Diabetes Mellitus: What Radiologists Need to Know

Laparoscopic mini-gastric bypass surgery is a safe and simple surgical intervention for treating morbid obesity and diabetes mellitus and is now being performed more frequently. Radiologists must be critical in their postoperative evaluation of these patients. In this pictorial review, we explain and illustrate the surgical technique, normal postoperative anatomy, and associated complications as seen on imaging examinations, including fluoroscopy and computed tomography.     

Biliary tree and cholecyst: post surgery imaging

Recently, with improvements in surgical techniques there has been a substantial reduction in the incidence of biliary complications of hepatobiliary surgery. Nevertheless, bile duct injuries and other post-cholecystectomy complications are a serious problem and a major cause of morbidity and mortality. Early complications may include bile duct injury caused by mistakenly placed clips, erroneous cutting of bile ducts based on misinterpretation of biliary anatomy, periductal bile leakage that causes edema, fibrosis and secondary stricturing, and ischemia due to injury to the right hepatic artery. Bile duct strictures are the most common of the late complications and can develop a few months or many years after surgery. Early detection and accurate diagnosis have a fundamental importance for the successful treatment of these complications. Therefore, early and meaningful application of the imaging methods immediately after detection of the first symptoms is essential. Peroperative ultrasound and direct iodine contrast application into the biliary tree (operative cholangiography) are highly important for immediate visualization of the complications during surgery. Ultrasound can be used to aid in identification of ductal structures and the cholangiogram should be obtained to document the anatomy. Plain abdominal film could be made in the patients in poor clinical conditions after biliary surgery. Oral cholecystography has largely been replaced by ultrasonography (US) for evaluation of cholelithiasis and complications like post-cholecystectomy fluid collections. The same methodology replaced the conventional intravenous cholangiography. Nowadays computed tomography (CT), endoscopic retrograde cholangiopancreatography (ERCP), magnetic resonance cholangiography (MRCP) and ultrasound (US) have essential roles as primary imaging modalities after biliary tree and gallbladder surgery in the evaluation of associated complications and residual biliary stones. We review the role of the imaging in complications after biliary tree and gallbladder surgery.     

Imaging evaluation of head and neck infections

Infections of the head and neck are frequent and usually have a good prognosis even though complications may sometimes be life threatening. In addition to airway compromise, intracranial and thoracic extension may occur. Diagnosis usually is made on clinical examination and imaging may play a significant role in assessing the extent of the disease, detecting complications and assist in surgical planning. The imaging protocol should be appropriate for the proposed diagnosis and suspected complications. CT of the soft tissues of the neck and chest is the imaging test of choice. Interpretation requires knowledge of the anatomy to understand the modalities of local and distant spread of the disease. Imaging evaluation is important but should not delay emergently needed treatment for entities such as epiglottitis and necrotizing fasciitis.     

MDCT in the diagnostic algorithm in patients with symptomatic atrial fibrillation

Atrial fibrillation(AF) is the most common supraventricular arrhythmia and a major cause of morbidity.Arrhythmogenic foci originating within the pulmonary veins(PVs) are an important cause of both paroxysmal and persistent AF.A variety of endovascular and surgical techniques have been used to electrically isolate the PV from the left atrium.Pulmonary venography for localization of the PV ostium can be difficult to perform during the ablation procedure.While the anatomy of the PV is patientspecific,non-invasive imaging techniques may provide useful diagnostic information prior to the intended intervention.In this context,multidetector computed tomography(MDCT) visualization of the left atrial and PV anatomy prior to left atrial ablation and PV isolation is becoming increasingly important.MDCT imaging provides pre-procedural information on the left atrial anatomy,including atrial size and venous attachments,and it may identify potential post-procedural complications,such as pulmonary vein stenosis or cardiac perforations.Here,we review the relevant literature and present the current"state-of-the-art"of left atrial anatomy,PV ostia as well as the clinical aspects of refractory AF with MDCT imaging protocols and procedural aspects of PV ablation.