Yifei Duan, Jennifer Sweet, Charles Munyon, and Jonathan Miller
Trigeminal neuralgia is often associated with nerve atrophy, in addition to vascular compression. The authors evaluated whether cross-sectional areas of different portions of the trigeminal nerve on preoperative imaging could be used to predict outcome after microvascular decompression (MVD).
A total of 26 consecutive patients with unilateral Type 1a trigeminal neuralgia underwent high-resolution fast-field echo MRI of the cerebellopontine angle followed by MVD. Preoperative images were reconstructed and reviewed by 2 examiners blinded to the side of symptoms and clinical outcome. For each nerve, a computerized automatic segmentation algorithm was used to calculate the coronal cross-sectional area at the proximal nerve near the root entry zone and the distal nerve at the exit from the porus trigeminus. Findings were correlated with outcome at 12 months.
After MVD, 17 patients were pain free and not taking medications compared with 9 with residual pain. Across all cases, the coronal cross-sectional area of the symptomatic trigeminal nerve was significantly smaller than the asymptomatic side in the proximal part of the nerve, which was correlated with degree of compression at surgery. Atrophy of the distal trigeminal nerve was more pronounced in patients who had residual pain than in those with excellent outcome. Among the 7 patients who had greater than 20% loss of nerve volume in the distal nerve, only 2 were pain free and not taking medications at long-term follow-up.
Trigeminal neuralgia is associated with atrophy of the root entry zone of the affected nerve compared with the asymptomatic side, but volume loss in different segments of the nerve has very different prognostic implications. Proximal atrophy is associated with vascular compression and correlates with improved outcome following MVD. However, distal atrophy is associated with a significantly worse outcome after MVD.
Yifei Duan, Carlito Lagman, Raleigh Ems, and Nicholas C. Bambakidis
The exact pathophysiological mechanisms underlying cerebral aneurysm formation remain unclear. Asymmetrical local vascular geometry may play a role in aneurysm formation and progression. The object of this study was to investigate the association between the geometric asymmetry of the middle cerebral artery (MCA) and the presence of MCA aneurysms and associated high-risk features.
Using a retrospective case-control study design, the authors examined MCA anatomy in all patients who had been diagnosed with an MCA aneurysm in the period from 2008 to 2017 at the University Hospitals Cleveland Medical Center. Geometric features of the MCA ipsilateral to MCA aneurysms were compared with those of the unaffected contralateral side (secondary control group). Then, MCA geometry was compared between patients with MCA aneurysms and patients who had undergone CTA for suspected vascular pathology but were ultimately found to have normal intracranial vasculature (primary control group). Parent vessel and aneurysm morphological parameters were measured, calculated, and compared between case and control groups. Associations between geometric parameters and high-risk aneurysm features were identified.
The authors included 247 patients (158 cases and 89 controls) in the study. The aneurysm study group consisted of significantly more women and smokers than the primary control group. Patients with MCA bifurcation aneurysms had lower parent artery inflow angles (p = 0.01), lower parent artery tortuosity (p < 0.01), longer parent artery total length (p = 0.03), and a significantly greater length difference between ipsilateral and contralateral prebifurcation MCAs (p < 0.01) than those in primary controls. Type 2 MCA aneurysms (n = 89) were more likely to be associated with dome irregularity or a daughter sac and were more likely to have a higher cumulative total of high-risk features than type 1 MCA aneurysms (n = 69).
Data in this study demonstrated that a greater degree of parent artery asymmetry for MCA aneurysms is associated with high-risk features. The authors also found that the presence of a long and less tortuous parent artery upstream of an MCA aneurysm is a common phenotype that is associated with a higher risk profile. The aneurysm parameters are easily measurable and are novel radiographic biomarkers for aneurysm risk assessment.
Hai-Feng Wang and Da-Ming Wang
James M. Wright, Alankrita Raghavan, Christina H. Wright, Berje Shammassian, Yifei Duan, Martha Sajatovic, and Warren R. Selman
Informed consent, when performed appropriately, serves many roles beyond simply obtaining the prerequisite medicolegal paperwork to perform a surgery. Prior studies have suggested that patient understanding is poor when verbal communication is the sole means of education. Virtual reality platforms have proven effective in enhancing medical education. No studies exist that have demonstrated the utility of virtual reality–facilitated informed consent (VR-IC) in improving the physician-patient alliance. The aim of this study was to determine the utility of VR-IC among patients providing consent for surgery and the impact of this educational and information technology–based strategy on enhancing the physician-patient alliance, patient satisfaction, and resident-physician perception of the consent process.
Prospective, single-site, pre- and postconsent surveys were administered to assess patient and resident perception of informed consent performed with the aid of VR-IC at a large tertiary academic medical center in the US. Participants were adult patients (n = 50) undergoing elective surgery for tumor resection and neurosurgical residents (n = 19) who obtained patient informed consent for these surgical procedures. Outcome measures included scores on the Patient-Doctor Relationship Questionnaire (PDRQ-9), the modified Satisfaction with Simulation Experience Scale, and the Maslach Burnout Inventory. Patient pre- and postconsent data were recorded in real time using a secure online research data platform (REDCap).
A total of 48 patients and 2 family members provided consent using VR-IC and completed the surveys pre- and postconsent; 47.9% of patients were women. The mean patient age was 57.5 years. There was a statistically significant improvement from pre- to post–VR-IC consent in patient satisfaction scores. Measures of patient-physician alliance, trust, and understanding of their illness all increased. Among the 19 trainees, perceived comfort and preparedness with the informed consent process significantly improved.
VR-IC led to improved patient satisfaction, patient-physician alliance, and patient understanding of their illness as measured by the PDRQ-9. Using VR-IC contributed to residents’ increased comfort in the consent-gathering process and handling patient questions. In an era in which satisfaction scores are directly linked with hospital and service-line outcomes and reimbursement, positive results from VR-IC may augment physician and hospital satisfaction scores in addition to increasing measures of trust between physicians and patients.
Shaarada Srivatsa, Yifei Duan, John P. Sheppard, Shivani Pahwa, Jonathan Pace, Xiaofei Zhou, and Nicholas C. Bambakidis
Mechanical thrombectomy is effective in acute ischemic stroke secondary to emergent large-vessel occlusion, but optimal efficacy is contingent on fast and complete recanalization. First-pass recanalization does not occur in the majority of patients. The authors undertook this study to determine if anatomical parameters of the intracranial vessels impact the likelihood of first-pass complete recanalization.
The authors retrospectively evaluated data obtained in 230 patients who underwent mechanical thrombectomy for acute ischemic stroke secondary to large-vessel occlusion at their institution from 2016 to 2018. Eighty-six patients were identified as having pure M1 occlusions, and 76 were included in the final analysis. The authors recorded and measured clinical and anatomical parameters and evaluated their relationships to the first-pass effect.
The first-pass effect was achieved in 46% of the patients. When a single device was employed, aspiration thrombectomy was more effective than stent retriever thrombectomy. A larger M1 diameter (p = 0.001), decreased vessel diameter tapering between the petrous segment of the internal carotid artery (ICA) and M1 (p < 0.001), and distal collateral grading (p = 0.044) were associated with first-pass recanalization. LASSO (least absolute shrinkage and selection operator) was used to generate a predictive model for recanalization using anatomical variables.
The authors demonstrated that a larger M1 vessel diameter, low rate of vessel diameter tapering along the course of the intracranial ICA, and distal collateral status are associated with first-pass recanalization for patients with M1 occlusions.