MR imaging of anterior knee pain: a pictorial essay.

Anterior knee pathology is a frequent cause of joint pain and limitation of function and mobility among patients presenting to an orthopaedic department. Proper recognition and treatment of pathologic conditions depend on the knowledge of normal anatomy and of the various abnormalities, which affect this area of the knee and may present with anterior knee pain. A broad array of benign and malignant processes may be manifested as anterior knee discomfort, and this common clinical entity is among the most frequent indications for MR imaging of the lower extremities. Clinical history and physical examination are also of paramount importance. The disorders can be categorized and differentiated primarily according to their location. Traumatic or non-traumatic disorders of the patella, patellar retinacula, quadriceps and patellar tendons and supra or infrapatellar fat pad can be the source of symptoms. This article includes a comprehensive pictorial essay of the characteristic MR features of common and uncommon disorders causing anterior knee pain. For accurate assessment of the aforementioned clinical problem, a radiologist should be able to identify typical MR imaging patterns that contribute in establishing the correct diagnosis and thus tailoring the appropriate therapy. Level of evidence IV.

Solid Pseudopapillary Tumor of the Pancreas: A Single-center Experience and Review of the Literature.

BACKGROUND: Solid pseudopapillary tumors (SPTs) of the pancreas are a rare occurrence, not exceeding 1-2% of all exocrine pancreatic tumors. SPT was first described in 1959 as "papillary tumor of the pancreas, benign or malignant" and affects mainly young women, in their second or third decade of age. These tumors are of low malignant potential, unclear pathogenesis, grow gradually and become considerably large before causing symptoms. A typical clinical presentation is often described by affected patients and, in some cases, an SPT is an incidental finding during the time the patient undergoes medical imaging studies for other health issues. SPT is frequently located at the head or tail of the pancreas. Metastases are rare but, when present, affect predominantly the liver. PATIENTS AND METHODS: We report a series of five SPT cases in female patients 13-47 years old, presenting with almost identical symptoms of upper abdominal discomfort and non-tender palpable mass. Two out of five patients also reported vomiting, nausea and poor appetite as co-existing non-diagnostic symptoms. Only one patient presented without any symptoms. Tumor location and dimensions varied. One patient underwent a pancreatoduodenectomy (Whipple's procedure), while the remaining patients underwent distal pancreatectomy with concomitant splenectomy. RESULTS: Perioperative morbidity and mortality was zero. All five patients are disease-free at a follow-up from 3 months to 13 years. Histopathology reports supported the diagnosis of SPT and no metastatic disease was present in any of the patients. CONCLUSION: The overall prognosis of SPT of the pancreas is excellent due to its favorable biological features, even in the presence of distal metastasis. Although surgical resection is often curative, a close follow-up is advised in order to diagnose a possible local recurrence or distal metastasis and choose the proper therapeutic option for the patients.