Treatment of Supratentorial Spontaneous Intracerebral Hemorrhage Using Image-Guided Minimally Invasive Surgery: Initial Experiences of a Flat Detector CT–Based Puncture Planning and Navigation System in the Angiographic Suite

Discussion

The prolonged operation time is one of the limitations for removing clot using craniotomy. In our experience with this FDCT-based puncture planning and navigation method, we were able to complete the procedure in around 40 minutes. This procedure time was significantly shorter than that of the conventional craniotomy treatment, which usually takes around 3 hours in our institute. It was also slightly faster than other reported image-guided surgery times, such as 89 minutes using intraoperative CT¹⁴ and 85 minutes using endoscopic navigation.⁷ The shortened workflow was mainly a benefit from the convenience of performing intraprocedural FDCT within the angiographic suite. FDCT, in general, has lower resolution than that of volumetric CT, but it is sufficient for the application of intracranial hematoma evacuation. First, the attenuation difference of the skull, the hemorrhage, and the normal brain tissue within the brain is large enough to be easily differentiated in a reconstructed 3D FDCT image (as shown in Fig 2). Second, the respiratory motion and the cardiac rhythm only minimally affect the brain tissue; hence its immobility could further enhance the image quality.

The key factor for hemorrhage evacuation through burr-holes is the precise positioning of the drainage catheter. The maximum deviation between planned and actual position of the drainage catheter was found to be less than 7 mm in our study. Moreover, postprocedural FDCT indicated that the catheter tips arrived at the center of the hemorrhage in all cases. The accurate placement of the catheter in our study was mainly due to the real-time guidance of the fluoroscopic image with overlaid planned needle path. The surgeon could make a slight adjustment to the trajectory path simultaneously as the catheter advanced to the planned location while watching the real-time fluoroscopy with overlaid planning needle path. By doing this, we could avoid the multiple punctures that tend to have a much higher chance of brain tissue damage than a single attempt. We also noticed that the small deviation still existed in some cases, and that could be due to the lack of bilateral guidance during catheter advancement. This should be taken into consideration in the future version of the needle guidance tool.

Theoretically, the accurate placement of the evacuation catheter could lead to better treatment outcome. The treatment outcome evaluation based on our patients' condition at discharge and 6-month follow-up supported this assumption. In our study, no patient showed recurrent bleeding or technique-related postsurgery complication, whereas the reported studies have shown that the complication rate of the stereotactic aspiration treatment was 17.9%–37.3%, and the rebleeding incidence was 5%–13.3%.^{6,15⇓⇓⇓–19}

For the FDCT/fluoro-assisted hematoma evacuation in the angiographic suite, our experiences in 21 hypertensive patients with ICH were concluded as follows: 1) Puncture site selection: The frontal approach was preferred over the temporal approach because of the consideration that there is relatively less neurologic and vascular traffic in the frontal lobe area. In addition, puncturing and advancing the catheter from the forehead was convenient for operators because the bull's eye view and progression views in the C-arm were nearly vertical and horizontal in direction, with minimal interference on operations and anesthesia. 2) Operation procedures: We suggested generating the burr-hole before the acquisition of planning FDCT for this specific application on a human head. In this way, the impact of the twist drill on the scalp and head shift will be excluded from the puncture planning; 3) Surgery timing: At least 24 hours after the onset of the hemorrhage. Although there were extensive reports of the benefit of ultra-early and early removal of the hematoma in the literature, the surgery timing is still controversial due to a lack of evidence-based support. In our opinion, the hematoma drainage could be easier and the risk of rebleeding could be lower when we allow at least 1 day for hematoma to liquefy.

One of the important benefits of this demonstrated FDCT/fluoro-assisted minimally invasive surgery was the low cost of the procedure, as it can be performed in the traditional angiographic suite, without adding extra cost to patients for specialized devices. The shortened operation time compared with craniotomy also significantly reduced the clinical cost of this procedure. This is especially useful for underdeveloped countries that experience high patient volume but have limited medical resources. In this way, more low-income patients will have the chance to receive timely treatment. Moreover, given the low cost and high performance of the procedure, this could potentially encourage more eligible patients to be recruited into a future prospective study.

One limitation of this study is that only patients with indications for surgery were included in this retrospective study. Although we attempted to compare the treatment outcome with published meta-analysis results from large-scale clinical trials, the comparison was not based on the same patient baseline. Retrospectively matching the surgery group with patients receiving medical treatment only, however, could bring uncertainties such as different medical treatment strategies and varied treatment timings into comparison because patient treatments were originally conducted without clear guidelines. Hence, though the feasibility of this FDCT/fluoro-guided ICH evacuation was demonstrated, one of our immediate future works is to initiate a multicenter, prospective trial that compares the immediate and long-term treatment outcome of combined FDCT/fluoro-assisted minimally invasive surgery and urokinase treatment with conventional medical therapy only for patients with ICH.