E5190. Atypical Popliteal Fossa Lesions: A Differential You Knee(d) to Know
  1. Daniel Stahl; Rutgers, The State University of New Jersey
  2. Cornelia Wenokor; Rutgers, The State University of New Jersey
Although popliteal cysts are the most common pathology of the popliteal fossa, there are a plethora of other entities that occur in this region, which include neoplastic, arthritic, infectious, vascular, neurologic, and traumatic etiologies. The purpose of this educational exhibit is to provide an overview of popliteal fossa anatomy and present imaging cases across these aforementioned categories with discussion of pathology and corresponding radiologic features for multiple modalities.

Educational Goals / Teaching Points
The educational goals of this presentation are to discuss a broad differential diagnosis of popliteal fossa lesions, review important anatomical structures of the popliteal fossa, categorize pathologies by their respective etiologies, and highlight key diagnostic radiologic features of these entities.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
This educational exhibit will show an assortment of diagnostic imaging (MRIs, CTs, ultrasounds, and radiographs) for various popliteal fossa pathologies, including hemangioma, synovial osteochondromatosis, myxoid liposarcoma, NF malignant peripheral nerve sheath tumor, stump neuroma, schwannoma, ancient schwannoma, soft tissue chondroma, acute DVT, chronic DVT, lymphoma, paraosteal osteosarcoma, fibrolipomatous hamartoma sciatic nerve, peroneal nerve ganglion, CPPD, scleroderma, lupus calcinosis cutis, fibromatosis, and a sentinel cyst.

The popliteal fossa is a compact structure comprised of various anatomical components. As such, several pathologies can develop in this location (i.e., neoplastic, infectious, arthritic, vascular, neurologic, and traumatic etiologies), each with distinct radiologic features.