Endoscope-assisted resection of cavernous angioma at the foramen of Monro: a case report

Matsumoto et al. SpringerPlus (2016) 5:1820 DOI 10.1186/s40064-016-3538-x Open Access CASE STUDY Endoscope‑assisted resection of cavernous angioma at the foramen of Monro: a case report Yuji Matsumoto1, Kazuhiko Kurozumi1* , Yousuke Shimazu2, Tomotsugu Ichikawa1 and Isao Date1 Abstract Introduction: Intraventricular cavernous angiomas are rare pathological entities, and those located at the foramen of Monro are even rarer. We herein present a case of cavernous angioma at the foramen of Monro that was successfully treated by neuroendoscope-assisted surgical removal, and review the relevant literature. Case presentation: A 65-year-old woman had experienced headache and vomiting for 10 days before admission to another hospital. Magnetic resonance imaging (MRI) showed a mass at the foramen of Monro, and obstructive hydrocephalus of both lateral ventricles. The patient was then referred to our hospital. Neurological examination on admission to our hospital showed memory disturbance (Mini-Mental State Examination 20/30) and wide-based gait. A cavernous angioma at the foramen of Monro was diagnosed based on the typical popcorn-like appearance of the lesion on MRI. The lesion was completely removed by neuroendoscope-assisted transcortical surgery with the Viewsite Brain Access System (Vycor Medical Inc., Boca Raton, FL), leading to a reduction in the size of the ventricles. The resected mass was histologically confirmed to be cavernous angioma. The patient’s symptoms resolved immediately and there were no postoperative complications. Conclusion: Minimally invasive neuroendoscope-assisted surgery was used to successfully treat a cavernous angioma at the foramen of Monro. Keywords: Cavernous angioma, Foramen of Monro, Neuroendoscope-assisted surgery Background Intraventricular cavernous angiomas are rare pathological entities, constituting 2.5–10.8 % of cerebral cavernous angiomas (Kivelev et al. 2010); those localized at the foramen of Monro are even rarer. To the best of our knowledge, only 16 cases of cavernous angioma at the foramen of Monro have been previously reported (Lee et al. 2012; Bhatia et al. 2013; Winslow et al. 2015). Surgical removal was performed in all previous cases. Most removals were performed via microsurgery; however, neuroendoscopic surgery is being used increasingly more frequently. We herein describe a recent case of a cavernous angioma at *Correspondence: ‑u.ac.jp 1 Department of Neurological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2‑5‑1 Shikata‑cho, Okayama, Okayama 700‑8558, Japan Full list of author information is available at the end of the article the foramen of Monro that was successfully treated using neuroendoscope-assisted surgery. Case presentation A 65-year-old woman with a history of hyperlipidemia had experienced headache and vomiting for 10 days before admission to another hospital. Magnetic resonance imaging (MRI) showed enlargement of both lateral ventricles and a mass at the foramen of Monro. The patient was then referred to our hospital. Neurological examination on admission to our hospital showed memory disturbance (Mini-Mental State Examination 20/30) and a wide-based gait disturbance. Computed tomography (CT) showed a 16 mm mildly hyperdense mass with no calcification at the foramen of Monro, and the mass was causing obstructive hydrocephalus. MRI revealed a well-delineated mass at the © The Author(s) 2016. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Matsumoto et al. SpringerPlus (2016) 5:1820 foramen of Monro with heterogeneous signal intensity on both T1- and T2-weighted images; the mixed-signal core appeared as a popcorn-like lesion typical of cavernous angioma (Fig. 1). Gadolinium-enhanced T1-weighted imaging revealed mild enhancement of the mass (Fig. 2). There were no vascular abnormalities on CT angiography or CT venography. We considered a colloid cyst, central neurocytoma, subependymoma, ependymoma, low grade astrocytoma, and arteriovenous malformation as differential diagnosis; however, despite the unusual location of the mass, a diagnosis of intraventricular cavernous angioma was made because of its typical appearance on MRI. We performed endoscope-assisted transcortical removal of the mass (Fig. 3). The entry point was made using the StealthStation S7 navigation system (Medtronic Inc., Louisville, CO), and a flexible videoscope (VEFV, Olympus Corporation, Tokyo, Japan) was inserted. Intraoperative neuroendoscopic imaging revealed a reddish lobular mass with a hematoma and obstruction of the foramen of Monro. We observed the cavum septum pellucidum because of the high intracranial pressure Page 2 of 7 associated with hydrocephalus. After right frontal minicraniotomy, the Viewsite Brain Access System (Vycor Medical Inc., Boca Raton, FL) was inserted (Raza et al. 2011); we used the 17 mm wide retractor in the 7 cm length. Endoscope-assisted surgery with the Viewsite was performed with technique similar to microsurgery. A 2.7 mm rigid endoscope (Karl Storz, Tuttlingen, Germany) fixed by UniArm (Mitaka Kohki, Tokyo, Japan) was inserted. The working ambience was air because of its advantages over fluid ambience especially when dealing with a relatively vascularized pathology. Other microsurgical instruments were used parallel to the endoscope. The endoscope served only as an optic apparatus. We used the Viewsite as an access port to enable dual instrumentation (endoscope and microsurgical instrumentation). The tumor was bluntly dissected from the ventricle wall, and total en bloc resection of the lesion was performed by one surgeon using the two-handed technique. Bleeding was well controlled with irrigation and bipolar coagulation. The resected tumor was reddish and consisted mainly of clotted blood vessels and xanthochromic tissue. Fig. 1 Computed tomography and magnetic resonance imagings. a There was a mild hyperintense 16-mm-diameter mass without calcification at the foramen of Monro causing obstructive hydrocephalus. b, c T1- and T2-weighted images showed the well-delineated mixed-signal heterogeneous core. The typical peripheral hemosiderin rim of low signal intensity was not seen on T2-weighted imaging. d No perilesional edema was presented on the fluid-attenuated inversion recovery magnetic resonance image. e Diffusion-weighted imaging showed an isointense mass; only a portion of the mass was hyperintense. f T2-star-weighted imaging showed a hypointense mass Matsumoto et al. SpringerPlus (2016) 5:1820 Page 3 of 7 Fig. 2 a Axial, b coronal, and c sagittal gadolinium-enhanced T1-weighted imaging demonstr (...truncated)