A term 8-day-old male presented to an outside emergency department with acute respiratory distress. Prenatal history was unremarkable except for prenatal diagnosis of a right sided nonspecific congenital lung malformation (CLM), possibly a congenital pulmonary airway malformation (CPAM). Anatomy ultrasound reported a right mid-lung echogenic lesion measuring with two small internal cysts. Fetal MRI demonstrated a non-segmental T2-hyperintense lesion in the peripheral right lower lobe with two small peripheral cysts and no feeding vessel. The lung mass to volume ratio was 0.05 with favorable observed to expected total fetal lung volumes. Initial examination revealed absent breath sounds on the right, and chest radiograph confirmed a large right tension pneumothorax. A chest tube was placed, and he was transferred to a higher level of care. CT angiography of the chest demonstrated a pleural-based multicystic lesion with internal air–fluid levels and focal solid nodular components, without a systemic feeding vessel. On day 12 of life, he underwent a right lower lobe wedge resection. Intraoperatively, surgeons noted an exophytic cystic lesion arising from the medial aspect of the right lower lobe on a narrow stalk. Pathology findings revealed a multicystic lesion consistent with Type 1r pleuropulmonary blastoma (PPB). Follow up genetic testing revealed a positive test for DICER-1 genetic mutation. 6 month follow up CT was negative and he continues to be followed at higher care institution. PPB is a rare, aggressive tumor originating from primitive mesenchymal cells of the lung or pleuraprimarily affecting infants and young children. PPB occurs in 1 in 250,000 live births and is associated with DICER1 gene mutations. Early detection is essential, offering a window for curative surgery before the disease progresses. PPB is difficult to distinguish from a benign CLM and is more commonly diagnosed in infancy. As of 2022, fewer than 6 confirmed cases of PPB were diagnosed prenatally. Despite the diagnostic overlap between PPB and CLM, pediatric radiologists play a key role in raising early suspicion, guiding surgical planning, and prompting genetic evaluation when imaging features deviate from typical benign patterns. This case highlights the diagnostic complexity and clinical features of the rare occurrence of prenatal diagnosis of pleuropulmonary blastoma, a malignancy that may be underrecognized due to its overlap with benign cystic lung lesions. Read More

Meeting name: SPR 2026 Annual Meeting , 2026

Authors: Gardner Kyle, Gagnon Marie-helene

Keywords: DICER1, Congenital, Pleuropulmonary Blastoma

Objective: Describe the embryologic origin and developmental anatomy of the torcular pathology. Identify the key MRI and MR venography characteristics of torcular pseudomass that distinguish it from dural venous sinus thrombosis and other posterior fossa lesions. Recognize the typical clinical scenarios in which torcular pseudomass is discovered and understand its benign, self-limiting natural history. Learning Points: Torcular pseudomass is a benign, self-limiting developmental variant in infants, not true mass. Appears midline, as a non-enhancing, extra-axial soft-tissue prominence posterior to the torcular Herophili on MRI Differential diagnoses include dural venous sinus thrombosis, dermoid cyst, and neoplasm. No enhancement or venous obstruction on MRV distinguishes it from thrombosis. Follow-up is rarely required unless associated abnormalities are suspected. Recognition of this entity prevents unnecessary imagination or surgical intervention. Most cases resolve spontaneously by 12–18 months of age. Discussion: Torcular pseudomass is a non-pathologic developmental variant located posterior to the torcular Herophili, the confluence of dural venous sinuses. It represents persistent mesenchymal tissue that fails to fully regress after birth. While uncommon, it is increasingly recognized with the wider use of MRI in infants. This benign entity typically appears between 2–6 months of age and resolves spontaneously within the first year of life. The overall prevalence is unknown, but literature shows on MRI series estimate Torcular pseudomass is found an incidental in up to 1–2% of pediatric neuroimaging studies. Awareness of this variant is essential, as it can be mistaken for dural venous sinus thrombosis, dermoid cyst, or posterior fossa tumor. Misdiagnosis may lead to unnecessary interventions such as anticoagulation or biopsy. Read More

Meeting name: SPR 2026 Annual Meeting , 2026

Authors: Gardner Kyle, Kuwabara Michael

Keywords: Congenital, MRI Brain