Low-Dose Three-Dimensional Rotational Angiography for Evaluating Intracranial Aneurysms: Analysis of Image Quality and Radiation Dose

Objective@#This study aimed to evaluate the image quality and dose reduction of low-dose three-dimensional (3D) rotational angiography (RA) for evaluating intracranial aneurysms. @*Materials and Methods@#We retrospectively evaluated the clinical data and 3D RA datasets obtained from 146 prospectively registered patients (male:female, 46:100; median age, 58 years; range, 19–81 years). The subjective image quality of 79 examinations obtained from a conventional method and 67 examinations obtained from a low-dose (5-seconds and 0.10-μGy/frame) method was assessed by two neurointerventionists using a 3-point scale for four evaluation criteria. The total image quality score was then obtained as the average of the four scores. The image quality scores were compared between the two methods using a noninferiority statistical testing, with a margin of -0.2 (i.e., score of low-dose group – score of conventional group). For the evaluation of dose reduction, dose-area product (DAP) and air kerma (AK) were analyzed and compared between the two groups. @*Results@#The mean total image quality score ± standard deviation of the 3D RA was 2.97 ± 0.17 by reader 1 and 2.95 ± 0.20 by reader 2 for conventional group and 2.92 ± 0.30 and 2.95 ± 0.22, respectively, for low-dose group. The image quality of the 3D RA in the low-dose group was not inferior to that of the conventional group according to the total image quality score as well as individual scores for the four criteria in both readers. The mean DAP and AK per rotation were 5.87 Gy-cm2 and 0.56 Gy, respectively, in the conventional group, and 1.32 Gy-cm2 (p < 0.001) and 0.17 Gy (p < 0.001), respectively, in the low-dose group. @*Conclusion@#Low-dose 3D RA was not inferior in image quality and reduced the radiation dose by 70%–77% compared to the conventional 3D RA in evaluating intracranial aneurysms.

Complications of Cranioplasty Following Decompressive Craniectomy: Risk Factors of Complications and Comparison Between Autogenous and Artificial Bones / 대한신경손상학회지

Objectives@#Craniectomy is widely performed to lower the intracranial pressure in various conditions, such as traumatic brain injury, stroke, or brain swelling. Several complications can occur after craniectomy and cranioplasty, which significantly affect the prognosis of the patients after surgery. We studied the complications of craniectomy and cranioplasty and the factors affecting prognosis after the operation. @*Methods@#Patients who underwent cranioplasty after craniectomy at Daejeon St. Mary’s Hospital from 2015 to 2021 were included. We retrospectively reviewed their medical records and images. All patients were classified according to their sex, age, clinical grade, and diagnosis. Complications after craniectomy and cranioplasty were investigated for 1 year after surgery. The complications included postoperative hemorrhage, infection, hydrocephalus, and bone resorption. @*Results@#This study included 104 patients. Complications after decompressive craniectomy were significantly frequent in patients with hypertension history (p=0.03). In contrast, complications of cranioplasty were significantly frequent in patients with history of diabetes mellitus, hepatic failure, or trauma (p=0.03, p<0.01, and p=0.01, respectively). Artificial bones were used more frequently than autologous bones in patients with trauma (p=0.03); however, there was no difference in the incidence of complications between them (p=0.64). @*Conclusion@#Hypertension is a significant risk factor for decompressive craniectomy complications, especially rebleeding. Diabetes, hepatic failure, and trauma are significant risk factors for cranioplasty complications. There was no statistical difference in the incidence of complications between the use of autologous and artificial bones.

Low-Dose 3D Rotational Angiography in Measuring the Size of Intracranial Aneurysm: In Vitro Feasibility Study Using Aneurysm Phantom / 신경중재치료의학

Purpose@#Three-dimensional (3D) measurement of intracranial aneurysms is important in planning endovascular treatment, and 3D rotational angiography (RA) is effective in accurate measurement. The purpose of this study was to evaluate the feasibility of low dose 3D RA (5 seconds 0.10 μGy/frame) in measuring an intracranial aneurysm using an in vitro phantom. @*Materials and Methods@#We investigated an in vitro 3D phantom of an intracranial aneurysm with 10 acquisitions of 3D RA with a conventional dose (5 seconds 0.36 μGy/frame) and 10 acquisitions with a low-dose (5 seconds 0.10 μGy/frame). 3D size and neck diameters of the aneurysm were measured and compared between the 2 groups (conventional and low-dose) using noninferiority statistics. @*Results@#The aneurysm measurements were well-correlated between the 2 readers, and noninferiority in the measurement of aneurysmal size of low-dose 3D RA was demonstrated, as the upper margin of the 1-sided 97.5% confidence interval did not cross the pre-defined noninferiority margin of 0.2 mm by the 2 readers. @*Conclusion@#Low-dose (5 seconds 0.10 μGy/frame) cerebral 3D RA is technically feasible and not inferior in in vitro 3D measurement of an intracranial aneurysm. Thus, low-dose 3D RA is promising and needs further evaluation for its clinical utility in the planning of endovascular treatment of an intracranial aneurysm.

The Risk Factors for Hydrocephalus and Subdural Hygroma after Decompressive Craniectomy in Head Injured Patients

OBJECTIVE: The present study aims to investigate 1) the risk factors for hydrocephalus and subdural hygroma (SDG) occurring after decompressive craniectomy (DC), and 2) the association between the type of SDG and hydrocephalus. METHODS: We retrospectively reviewed the clinical and radiological features of 92 patients who underwent DC procedures after severe head injuries. The risk factors for developing post-traumatic hydrocephalus (PTH) and SDG were analyzed. Types of SDGs were classified according to location and their relationship with hydrocephalus was investigated. RESULTS: Ultimately, 26.09% (24/92) of these patients developed PTH. In the univariate analyses, hydrocephalus was statically associated with large bone flap diameter, large craniectomy area, bilateral craniectomy, intraventricular hemorrhage, contralateral or interhemisheric SDGs, and delayed cranioplasty. However, in the multivariate analysis, only large craniectomy area (adjusted OR=4.66; p=0.0239) and contralateral SDG (adjusted OR=6.62; p=0.0105) were significant independent risk factors for developing hydrocephalus after DC. The incidence of overall SDGs after DC was 55.43% (51/92). Subgroup analysis results were separated by SDG types. Statistically significant associations between hydrocephalus were found in multivariate analysis in the contralateral (adjusted OR=5.58; p=0.0074) and interhemispheric (adjusted OR=17.63; p=0.0113) types. CONCLUSION: For patients who are subjected to DC following severe head trauma, hydrocephalus is associated with a large craniectomy area and contralateral SDG. For SDGs after DC that occur on the interhemispherical or controlateral side of the craniectomy, careful follow-up monitoring for the potential progression into hydrocephalus is needed.

Post-Traumatic Arteriovenous Fistula of the Scalp

Arteriovenous fistula of the scalp is relatively rare disease. We report a traumatic arteriovenous fistula of the scalp treated with complete surgical excision and review the literature with regard to etiology, pathogenesis, and management of these unusual lesions.