[Ovarian endometriosis cyst with iodine 131 uptake : first case of false positive in the follow up for differentiated thyroid carcinoma]. / Kyste endométriosique ovarien fixant l'iode 131 : premier cas de faux positif dans le suivi d'un cancer différencié de la thyroïde.

A whole body scan is performed after a radioiodine treatment in patients with differentiated thyroid carcinoma. This scan is useful coupled with thyroglobulin level for the patient's management. When unusual uptake is found, investigations have to be done to eliminate thyroid metastasis. A 28-year old woman underwent a total thyroidectomy for micro papillary carcinoma. Two years and a half after, ultrasonography of the neck showed a small lymph node in homolateral side of carcinoma. It was decided to begin treatment with iodine 131. The post-therapeutic scan showed an abnormal pelvic uptake. IRM found no osseous abnormality but an ovarian lesion. After surgery, histological diagnosis was an endometriosis cyst without thyroid or tumoral cells. Abdominal ou pelvic iodine false positive are rare. Ovarian cysts may be the cause of false positive radioiodine uptake. Endometriosis cyst was not previously described and the mecanism of iodine uptake is not clear.

[Pain in the internal knee compartment]. / Douleur du compartiment interne du genou.

The anatomical classification of the traumatic or non traumatic lesion gives a mnemotechnical list which assists in the etiological search for pain of the inner aspect of the knee: skin, sub cutaneous tissue, medial lateral ligament, meniscus, cartilage, sub chondral bone, cruciate ligaments. Each mean of imaging detect specific lesions according to its technical capabilities: standard X Ray film, arthrography, CT scanner, MRI, bone scintigraphy, and echography. In practice, strategy is adapted to the clinical presentation, traumatic or non traumatic. In emergency situations, one is looking for bone, ligamentous, and meniscus lesions. Without acute traumatism, one can discover ligamentous tear sequellae (Pelligrini Stieda's ossifications), transient osteoporosis (algodystrophy), degenerative lesions (arthrosis) of the inner compartment. Always remember "close to the knee", it is necessary to check for more serious infectious or tumoral pathology. If standard plain films remain the first means of examination, and are still useful, MRI is becoming increasingly necessary for a complete anatomical evaluation.