Fig. 1

Microsurgical treatment of lumbar paravertebral tumors via lateral retroperitoneal approach. A MRI T1-weighted: a round-like paravertebral tumor (white arrow)at the posterior side of the kidney in the retroperitoneum, low signal. B MRI T2-weighted: small amount of mixed and uneven high signal, round-like tumor (white arrow). C MRI Gad-enhanced T1-weighted: axial view, a round-like tumor (white arrow) posterior to the kidney can be observed, significantly enhanced. D MRI Gad-enhanced T1-weighted: coronal view, a round-like tumor (white arrow) can be observed at L1–2 vertebral body level. E Intraoperative image: a 14 cm deep retractor fully exposes the tumor after retraction. F Postoperative image: The tumor was completely resected along the inner surface of the capsule, about 4 cm in diameter. G Postoperative image: the surgical incision length is about 7 cm. H, I Postoperative MRI image: image of retroperitoneal space, complete removal of the tumor (white arrow) located posterior to the kidney