Collision tumors are rare neoplasms defined by the presence of two distant tumors in the same organ without any histological intermixing. Ovarian tumors are often asymptomatic during the early stages and become symptomatic when increased in size causing vague abdominal pain, abdominal distention, vomiting, and frequent urination. We report here a case of a 28-year-old female who presented with a history of worsening abdominal pain and distension. An abdominopelvic ultrasound scan showed a huge complex mass occupying the pelvic area with non-visualization of the left ovary suggesting an ovarian origin; further characterization by cross-sectional imaging by both CT and MRI were performed confirming a left ovarian complex mass containing multiseptated cystic and fat component at the same time along with massive ascites. After surgical resection of the mass, histopathology revealed mucinous cystadenoma coexisting with cystic teratoma.

Spinal dural arteriovenous fistulae (SDAVF) are rare diseases that exhibit abnormal connections between arteries and veins. They are even rarer in the pediatric population and pose diagnostic and treatment challenges for physicians. Its presentation varies depending on the site and size of the SDAVF. Multiple management options are available, which are usually tailored depending on the patient's condition. Here, we present a rare case of SDAF in a four-year-old girl who initially presented with bilateral lower limb weakness. The patient was then treated successfully using primary major fistula point stenting and intrastent coiling, with complete closure achieved. Full recovery was achieved over the course of follow-ups. The deep analysis of SDAVF, its classification, and the utilization of the best available endovascular tools by a dedicated neurovascular team offer the best outcome in dealing with complex spinal neurovascular pathologies.