Related Experiment Video
Updated: Feb 22, 2026
Microsurgical Clip Obliteration of Middle Cerebral Aneurysm Using Intraoperative Flow Assessment
Published on: September 25, 2009
Intraoperative FLOW 800 Analysis for Intramedullary Cystic Lesion: A Technical Case Report
Masahiro Sawada1, Toshihiro Munemitsu1, Masato Hojo1
1Department of Neurosurgery, Shiga Medical Center for Adults, Moriyama, Japan.
Background And Importance:
During intramedullary lesion surgery, the lesion site and the posterior median sulcus (PMS) should be accurately identified prior to myelotomy to avoid severe injury of the posterior funiculus. However, intramedullary lesions are fundamentally invisible until the myelotomy is performed. Furthermore, the PMS location is frequently unclear due to lesion-induced swelling or distortion of the spinal cord. Intraoperative indocyanine green videoangiography (ICG-VA) followed by FLOW 800 analysis, which shows vascularization of the spinal parenchyma, may provide a solution for these problems in specific cases.
Clinical Presentation:
A 61-year-old woman suffering from claudication visited our department. Magnetic resonance imaging (MRI) revealed a cystic lesion at the level of Th11. A solid portion was not detected in the T1-weighted images following gadolinium administration. We made a diagnosis of ventriculus terminalis and performed a lesion resection. Prior to opening the PMS, ICG-VA was performed, which revealed an avascular area representing the intramedullary cyst. The PMS was the most avascular area observed in the time-intensity analysis executed using FLOW 800 software (Zeiss, Oberkochen, Germany). Thus, it was helpful in determining the site for myelotomy, which should be performed at the center of the extent of the lesion. The patient was discharged 23 days after the operation, ambulating independently.
Conclusion:
Intraoperative ICG-VA followed by FLOW 800 analysis was applied to a case of intramedullary cystic lesion. This technique may be helpful in performing safer intramedullary cystic lesion surgery because it enables visualization of the lesion location and confirmation of the PMS.
Insights
Intraoperative indocyanine green videoangiography (ICG-VA) with FLOW 800 analysis helps identify spinal cord lesions and the posterior median sulcus (PMS) during surgery. This technique improves the safety of intramedullary lesion resection by visualizing critical structures.
Area of Science:
- Neurosurgery
- Spinal Surgery
- Intraoperative Imaging
Background:
- Accurate identification of intramedullary lesions and the posterior median sulcus (PMS) is crucial before myelotomy to prevent posterior funiculus injury.
- Intramedullary lesions are often invisible until myelotomy, and spinal cord swelling can obscure the PMS.
- Intraoperative indocyanine green videoangiography (ICG-VA) with FLOW 800 analysis offers a potential solution by visualizing spinal parenchyma vascularization.
Observation:
- A 61-year-old patient with a Th11 intramedullary cystic lesion causing claudication underwent surgery.
- Pre-myelotomy ICG-VA revealed an avascular area corresponding to the cyst, with the PMS identified as the most avascular region.
- FLOW 800 analysis quantified the avascularity, aiding in precise myelotomy site selection.
Findings:
- ICG-VA followed by FLOW 800 analysis successfully visualized the intramedullary cystic lesion and confirmed the PMS location.
- The technique facilitated accurate determination of the myelotomy site, centered on the lesion's extent.
- The patient recovered well and was discharged independently.
Implications:
- Intraoperative ICG-VA with FLOW 800 analysis can enhance the safety of intramedullary cystic lesion surgery.
- This imaging approach aids in precise lesion localization and PMS confirmation, crucial for preventing neurological damage.
- The technique holds promise for improving surgical outcomes in complex spinal cord surgeries.
