Impact of preoperative mental health diagnosis on postoperative opioid use patterns in spine fusion surgery: A systematic literature review.

Opioids are frequently prescribed for patients undergoing procedures such as spinal fusion surgery for the management of chronic back pain. However, the association between a preoperative mental health illness, such as depression or anxiety, and opioid use patterns after spinal fusion surgery remain unclear. Therefore, we performed a systematic literature review in accordance with PRISMA guidelines to identify articles from the PubMed Database that analyzed the relationship between preoperative mental health illness and postoperative opioid usage after spinal fusion surgery on June 1, 2023. The Methodological Index for Nonrandomized Studies (MINORS) was utilized to evaluate the quality of included articles. Seven studies with 139,580 patients and a mean MINORS score of 18 ± 0.5 were included in qualitative synthesis. The most common spine surgery performed was lumbar fusion (59 %) and the mean age across studies ranged from 50 to 62 years. The range of postoperative opioid usage patterns analyzed ranged from 1 to 24 months. The majority of studies (6/7; 86 %) reported that a preoperative diagnosis of mental health illness was associated with increased opioid dependence after spinal fusion surgery. Preoperative use of opioids for protracted periods was shown to be associated with postoperative chronic opioid dependence. Consensus findings suggest that having a preoperative diagnosis of a mental health illness such as depression or anxiety is associated with increased postoperative opioid use after spinal fusion surgery. Patient comorbidities, including diagnoses of mental health illness, must be considered by the spine surgeon in order to reduce rates of postoperative opioid dependence.

Repeat Flow Diversion for Retreatment of Incompletely Occluded Large Complex Symptomatic Cerebral Aneurysms: A Retrospective Case Series.

BACKGROUND AND OBJECTIVES: Data regarding radiographic occlusion rates after repeat flow diversion after initial placement of a flow diverter (FD) in large intracranial aneurysms are limited. We report clinical and angiographic outcomes on 7 patients who required retreatment with overlapping FDs after initial flow diversion for large intracranial aneurysms. METHODS: We performed a retrospective review of a prospectively maintained database of cerebrovascular procedures performed at our institution from 2017 to 2021. We identified patients who underwent retreatment with overlapping FDs for large (>10 mm) cerebral aneurysms after initial flow diversion. At last angiographic follow-up, occlusion grade was evaluated using the O'Kelly-Marotta (OKM) grading scale. RESULTS: Seven patients (median age 57 years) with cerebral aneurysms requiring retreatment were identified. The most common aneurysm location was the ophthalmic internal carotid artery (n = 3) and basilar trunk (n = 3). There were 4 fusiform and 3 saccular aneurysms. The median aneurysm width was 18 mm; the median neck size for saccular aneurysms was 7 mm; and the median dome-to-neck ratio was 2.8. The median time to retreatment was 9 months, usually due to symptomatic mass effect. After retreatment, the median clinical follow-up was 36 months, MRI/magnetic resonance angiography follow-up was 15 months, and digital subtraction angiography follow-up was 14 months. Aneurysm occlusion at last angiographic follow-up was graded as OKM A (total filling, n = 1), B (subtotal filling, n = 2), C (early neck remnant, n = 3), and D (no filling, n = 0). All patients with symptomatic improvement were OKM C, whereas patients with worsened symptom burden were OKM A or B. Two patients required further open surgical management for definitive management of the aneurysm remnant. CONCLUSION: Although most patients demonstrated a decrease in aneurysm remnant size, many had high-grade persistent filling (OKM grades A or B) in this subset of mostly large fusiform aneurysms. Larger studies with longer follow-up are warranted to optimize treatment strategies for atypical aneurysm remnants after repeat flow diversion.

The obesity paradox and ventriculoperitoneal shunting in aneurysmal subarachnoid hemorrhage patients undergoing microsurgical clipping.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) can be devastating. Identifying predisposing factors is paramount in reducing aSAH-related mortality. Obesity's negative impact on health is well-established. However, the controversial "obesity paradox" in neurosurgery suggests that obesity may confer a survival advantage in SAH. We hypothesized that obesity would have a negative impact on outcomes following surgical clipping in aSAH. METHODS: A single-institution retrospective review was performed of aSAH patients undergoing surgical clipping from 2017 to 2021. Demographics and clinically relevant variables were collected. Obesity was defined as body mass index >30. Primary outcome was death or severe disability (mRS 4-6) at last follow-up. Secondary outcome was VPS placement. Multivariable Cox proportional-hazards model identified predictors of poor outcome. Kaplan-Meier curves identified survivorship differences between obese and non-obese patients. RESULTS: Poor outcome occurred in 11 of 52 total patients (21.2 %). There were no differences in demographics or distribution of Hunt Hess (HH), modified Fisher Grade (mFG), or external ventricular drain (EVD) placement between obese and non-obese patients. On univariate analysis, hypertension, older age, and non-obesity were predictive of poor outcome. On multivariable analysis, only obesity remained significant, suggesting a protective effect from poor outcome (HR 0.45 [0.21-0.95], p = 0.037). VPS placement occurred in 6 (11.5 %) patients for which obesity was not a significant predictor. CONCLUSIONS: Obesity may have a protective effect against poor outcome following surgical clipping in aSAH. Additionally, obesity does not appear to increase rate of EVD conversion to VPS. Thus, our study suggests that obesity should not preclude patients from open surgical intervention when clinically appropriate.

Outcomes After the Surgical Evacuation of Traumatic Acute Subdural Hematomas: The tASDH Risk Score.

BACKGROUND: Acute subdural hematoma (ASDH) is a common pathology following traumatic brain injury (TBI). There is sparse data on the prediction of clinical outcomes following traumatic ASDH (tASDH) evacuation. We investigated prognosticators of outcome following evacuation of tASDHs, with subset analysis in a cohort of octogenarians. We developed a scoring system for stratifying the risk of in-hospital mortality for patients undergoing tASDH evacuation. METHODS: A retrospective chart review was performed to identify all patients who underwent tASDH evacuation. Baseline clinical and demographic data including age, traumatic brain injury mechanism, admission Glasgow Coma Scale (GCS), and Rotterdam computed tomography Scale (RCS) were collected. In-hospital outcomes such as mortality and discharge disposition were collected. A scoring system (tASDH Score) which incorporates RCS (1-2 points), admissions GCS (0-1 points), and age (0-1 point) was created to predict the risk of in-hospital mortality following tASDH evacuation. RESULTS: Being an octogenarian (OR = 6.91 [2.20-21.71], P = 0.0009), having a GCS of 9-12 (OR = 1.58 [1.32-4.12], P = 0.027) or 3-8 (OR = 2.07 [1.41-10.38], P = 0.018), and having an RCS of 4-6 (OR = 3.49 [1.45-8.44], P = 0.0055) were independently predictive of in-hospital mortality. The in-hospital mortality rate was lower for those with a tASDH score of 1 (10%), compared to those with a score of 2 (12%), 3 (42%), and 4 (100%). CONCLUSIONS: Octogenarians with an RCS of 4-6 and an admission GCS <13 have a high risk of mortality following tASDH evacuation. Knowledge of which patients are unlikely to survive ASDH evacuation may help guide neurosurgeons in prognostication and goals of care discussions.

Prognosticators of Functional Outcome After Supratentorial Minimally Invasive Intracranial Hemorrhage Evacuation With Tubular Retractor Systems.

BACKGROUND AND OBJECTIVES: Prognosticators of good functional outcome after minimally invasive surgical (MIS) intracranial hemorrhage (ICH) evacuation are poorly defined. This study aims to investigate clinical and radiographic prognosticators of poor functional outcome after MIS evacuation of ICH with tubular retractor systems. METHODS: Single-center retrospective review of adult (age ≥18 years) patients who underwent surgical evacuation of a spontaneous supratentorial ICH evacuation using tubular retractors from 2013 to 2022 was performed. Clinical and radiographic factors, such as antiplatelet/anticoagulant use, initial NIH Stroke Scale, ICH score, premorbid modified Rankin Scale (mRS), intraventricular hemorrhage (IVH) severity according to the modified Graeb scale, and preoperative/postoperative ICH volume, were collected. The main outcome was poor functional outcome, defined as mRS score of 4-6 within 1 year postoperatively. RESULTS: Eighty-eight patients were included. Clinical follow-up data were available for 64 (73%) patients. Of those, 43 (67%) had a poor functional outcome. On multivariate Cox regression, postoperative ICH volume ≥15 mL (hazard ratio [HR] = 2.46 [95% CI: 1.25-4.87]; P = .010) and higher modified Graeb score (HR = 1.04 [95% CI: 1-1.1]; P = .035] significantly increased the risk of poor functional outcome. Elevated postoperative ICH volume was predicted by the presence of lobar ICH (vs nonlobar, OR = 3.32 [95% CI: 1.01-11.55]; P = .043) and higher preoperative ICH volume (OR = 1.05 [1.02-1.08]; P < .001). A minimum of 60% ICH evacuation yielded an improvement in mRS 4-6 rates (HR 0.3 [95% CI: 0.1-0.8], P = .013). In patients without IVH and with a >80% ICH evacuation, the rate of mRS 4-6 was 42% compared with 67% in the whole patient sample ( P = .017). CONCLUSION: Increased IVH volumes and residual postoperative ICH volumes are associated with poor functional outcome after MIS ICH evacuation. Postoperative ICH volume was associated with lobar ICH location as well as preoperative ICH volume. These factors may help to prognosticate patient outcomes and improve selection criteria for MIS ICH evacuation techniques.

A novel endoleak classification for intracranial aneurysm flow diversion: A retrospective case series.

BACKGROUND: Although flow diversion (FD) is safe and effective in the treatment of intracranial aneurysms, a subset tends to continue filling on serial angiography. Risk factors for failed flow diversion include old age, large aneurysm size, and overstenting an adjacent end-arterial vessel. The hemodynamic modes of persistent aneurysm filling, or 'endoleaks', after FD are poorly understood. This study aims to characterize the various types of endoleaks following aneurysmal FD. METHODS: We performed a retrospective review of a prospectively maintained database of all endovascular procedures performed at a single institution between 2017 and 2021. Patients were included if they demonstrated evidence of unique modes of intracranial aneurysm filling after FD. Data regarding treatment, follow-up angiography, as well as clinical course were collected. RESULTS: Five patients (mean age 50 years, four females) were included with mean 19-month angiographic follow-up. Five major endoleak types are proposed: Type 1 - due to graft porosity (A - low flow, B - high flow), Type 2 -through an overstented branch vessel, Type 3 - via stent migration no longer covering aneurysmal neck, Type 4 - endoleak due to malapposition of the stent wall, and Type 5 - endoleak via collateralization from adjacent blood vessels. All endoleak types were represented, except for the Type 4 endoleak. CONCLUSION: We propose an endoleak classification scheme to describe the hemodynamic modes of failure following FD of intracranial aneurysms. Future studies are needed to evaluate the natural history of aneurysmal filling following FD and retreatment success according to endoleak type.

Diffuse Axonal Injury Pattern Predicts Timing of In-Hospital Neurologic Recovery: A Retrospective Case Series.

BACKGROUND: Diffuse axonal injury (DAI) is a devastating traumatic neurologic injury with variable prognosis. Although outcomes such as mortality have been described, the time course of neurologic progression is poorly understood. We investigated the association between DAI neuroanatomic injury pattern and neurologic recovery timing. METHODS: A retrospective review of our institution's trauma registry identified patients diagnosed with DAI from 2017-2021. The neuroradiologist's review of a head computed tomography scan was used to score DAI severity. In-hospital neurologic examinations were reviewed, and the Glasgow Coma Scale (GCS) was calculated for all patients throughout the hospital stay. Categorical variables were analyzed using the Fisher exact test, and continuous variables were analyzed using the Kruskal-Wallis test. RESULTS: Nineteen DAI patients (grade 1 = 8; grade 2 = 1; grade 3 = 10) were included (mean age 31 years, 79% male). Mean Rotterdam computed tomography score, Injury Severity Scale, and admission GCS were comparable across DAI grades. Mean time in days to follow commands was shorter for those with grade 1 DAI (9.3) compared with grade 2 (17 days) or grade 3 (19 days) DAI (P = 0.02). Throughout hospitalization, patients with grade 1 DAI had higher motor (P = 0.006), eye (P = 0.001), and total GCS (P = 0.011) scores compared with those with grade 2 or 3 DAI. At the time of discharge, total GCS and the frequency of command following was similar across DAI grades. CONCLUSIONS: Patients with grade 1 DAI demonstrated the fastest short-term neurologic recovery, although final discharge neurologic examination was comparable across DAI grades. DAI classification can provide useful short-term prognostic information regarding in-hospital neurologic improvement.

Diagnostic yield of cerebral angiography for intracranial hemorrhage in young patients: A single-center retrospective analysis.

BACKGROUND: Intracranial hemorrhage (ICH) secondary to hypertension (HTN) classically occurs in the basal ganglia, cerebellum, or pons. Vascular lesions such as aneurysms or arteriovenous malformations (AVMs) are more common in younger patients. We investigated the utility of diagnostic subtraction angiography (DSA) in young hypertensive patients with non-lobar ICH. METHODS: A retrospective review (2013-2022) identified young (18-60 years) patients who underwent DSA for ICH. HTN history, ICH location, presence/absence of subarachnoid hemorrhage (SAH), and computed tomography angiography (CTA) findings were collected. The main outcome was DSA-positivity, defined as presence of an AVM, aneurysm, Moyamoya disease, reversible cerebral vasoconstriction syndrome, or dural arteriovenous fistula on DSA. RESULTS: Two hundred sixty patients were included, and the DSA-positivity rate was 19%.DSA-positivity was lower in hypertensive patients with ICHs in the cerebellum, pons, or basal ganglia compared to the rest of the patient sample (9% vs 26%, p = 0.0002, Fisher's exact test). We developed the ICH-Angio score (0-5 points) based on CTA findings, ICH location, HTN history, and presence of SAH to predict risk of underlying vascular lesions. DSA-positivity was lower in those with a score of 0 (0/62; 0%) compared to a score of 1 (5/52; 10%), 2 (17/48; 35%), 3 (10/20; 50%), 4 (5/6; 83%), or 5 (3/3; 100%). CONCLUSION: The ICH-Angio score was able to non-invasively rule out an underlying vascular etiology for ICH in up to one-third of patients. HTN, ICH location, CTA findings, and associated SAH can identify patients at low risk for harboring underlying vascular lesions.

Clinical Outcomes After Nonoperative Management of Large Acute Traumatic Subdural Hematomas in Older Patients: A Propensity-Scored Retrospective Analysis.

BACKGROUND: Large (≥1 cm) acute traumatic subdural hematomas (aSDHs) are neurosurgical emergencies. Elderly patients with asymptomatic large aSDHs may benefit from conservative management. OBJECTIVE: To investigate inpatient mortality after conservative management of large aSDHs. METHODS: Single-center retrospective review of adult patients with traumatic brain injury from 2018 to 2021 revealed 45 large aSDHs that met inclusion criteria. Inpatient outcomes included mortality, length of stay, and discharge disposition. Follow-up data included rate of surgery for chronic SDH progression. Patients with large aSDHs were 2:1 propensity score-matched to patients with small (<1 cm) aSDHs based on age, Injury Severity Scale, Glasgow Coma Scale, and Rotterdam computed tomography scale. RESULTS: Median age (78 years), sex (male 52%), and race (Caucasian 91%) were similar between both groups. Inpatient outcomes including length of stay ( P = .32), mortality ( P = .37), and discharge home ( P = .28) were similar between those with small and large aSDHs. On multivariate logistic regression (odds ratio [95% CI]), increased in-hospital mortality was predicted by Injury Severity Scale (1.3 [1.0-1.6]), Rotterdam computed tomography scale 3 to 4 (99.5 [2.1-4754.0), parafalcine (28.3 [1.7-461.7]), tentorial location (196.7 [2.9-13 325.6]), or presence of an intracranial contusion (52.8 [4.0-690.1]). Patients with large aSDHs trended toward higher progression on follow-up computed tomography of the head (36% vs 16%; P = .225) and higher rates of chronic SDH surgery (25% vs 7%; P = .110). CONCLUSION: In conservatively managed patients with minimal symptoms and mass effect on computed tomography of the head, increasing SDH size did not contribute to worsened in-hospital mortality or length of stay. Patients with large aSDHs may undergo an initial course of nonoperative management if symptoms and the degree of mass effect are mild.

Flow Diversion as Destination Treatment of Intracranial Mycotic Aneurysms: A Retrospective Case Series.

BACKGROUND: Mycotic aneurysms represent a rare type of intracranial aneurysm. Treatment options usually consist of coiling, clipping, or liquid embolization. Data regarding outcomes after flow diversion of mycotic aneurysms are sparse. OBJECTIVE: To present a single-center case series regarding our experience with FD as definitive treatment for ruptured mycotic aneurysms initially treated with coil embolization. METHODS: We retrospectively reviewed a prospectively maintained database of all cerebrovascular procedures performed at a single institution between 2017 and 2021 for cases that used FD for the management of intracranial mycotic aneurysms. Prospectively collected data included patient demographics, medical history, rupture status, aneurysm morphology, aneurysm location, and periprocedural complications. The main outcomes included neurological examination and radiographic occlusion rate on cerebral digital subtraction angiography. RESULTS: Three patients with 4 ruptured mycotic aneurysms that were initially treated with coil embolization were identified that required retreatment. The aneurysms were located along the middle cerebral artery bifurcation (n = 2), posterior cerebral artery P1/2 junction (n = 1), and basilar artery apex (n = 1), which all demonstrated recurrence after initial coil embolization. Successful retreatment using flow diverting stents was performed in all 3 patients. At the last angiographic follow-up, all aneurysms demonstrated complete occlusion. No patients suffered new periprocedural complications or neurological deficits after FD. CONCLUSION: Flow-diverting stents may be an effective treatment option for intracranial mycotic aneurysms that are refractory to previous endovascular coiling. Future studies are warranted to establish the associated long-term safety and clinical efficacy.

A Single-Center Retrospective Analysis of Intracranial and Spinal Solitary Fibrous Tumor/Hemangiopericytoma Clinical Outcomes: Sex Association With Aggressiveness.

BACKGROUND: Solitary fibrous tumor/hemangiopericytoma (SFT/HPCT) is a rare tumor characterized by high recurrence rate and metastatic potential, even after surgical resection. We report on the clinical outcomes and risk factors for metastasis and progression-free survival (PFS) of patients diagnosed with SFT/HPCT. METHODS: We retrospectively identified patients with intracranial or spinal SFT/HPCT who underwent surgical resection and/or radiation therapy at our institution between 1995 and 2021. Baseline demographics, tumor characteristics, and outcome data were collected, and factors associated with PFS and metastasis were analyzed. RESULTS: Thirty-four subjects (mean age, 46.4 years; 44% female) with a histopathologically proven diagnosis of SFT/HPCT were included; the median follow-up was 89.7 months. Twenty-two tumors were supratentorial (67%), 6 (18%) were infratentorial, and 5 (15%) were spinal. Eleven patients had documented occurrence of metastasis (32%). Detailed preoperative and postoperative data were available for 25 patients (74%) who received treatment at our institution after their initial diagnosis. Of those, 20 (80%) underwent gross total resection (GTR), and 12 (48%) received either adjuvant or salvage radiotherapy. Univariate analyses revealed that males had a shorter mean PFS compared with females (25 months vs. 78 months; P = 0.01), and that patients who underwent GTR had a longer mean PFS compared with those who underwent subtotal resection (54 months vs. 23 months; P = 0.02). Male sex was the sole risk factor for metastasis (odds ratio, 6.75; 95% confidence interval, 1.19-38.02). CONCLUSIONS: Our data demonstrate a strong association between male sex and the outcomes of shorter PFS and higher risk for metastases. Further research is warranted to understand the clinical characteristics and outcomes of this rare tumor.

Radiological Differentiation Between Intracranial Meningioma and Solitary Fibrous Tumor/Hemangiopericytoma: A Systematic Literature Review.

BACKGROUND: Intracranial solitary fibrous tumor (SFT) is characterized by aggressive local behavior and high post-resection recurrence rates. It is difficult to distinguish between SFT and meningiomas, which are typically benign. The goal of this study was to systematically review radiological features that differentiate meningioma and SFT. METHODS: We performed a systematic review in accordance with PRISMA guidelines to identify studies that used imaging techniques to identify radiological differentiators of SFT and meningioma. RESULTS: Eighteen studies with 1565 patients (SFT: 662; meningiomas: 903) were included. The most commonly used imaging modality was diffusion weighted imaging, which was reported in 11 studies. Eight studies used a combination of diffusion weighted imaging and T1- and T2-weighted sequences to distinguish between SFT and meningioma. Compared to all grades/subtypes of meningioma, SFT is associated with higher apparent diffusion coefficient, presence of narrow-based dural attachments, lack of dural tail, less peritumoral brain edema, extensive serpentine flow voids, and younger age at initial diagnosis. Tumor volume was a poor differentiator of SFT and meningioma, and overall, there were less consensus findings in studies exclusively comparing angiomatous meningiomas and SFT. CONCLUSIONS: Clinicians can differentiate SFT from meningiomas on preoperative imaging by looking for higher apparent diffusion coefficient, lack of dural tail/narrow-based dural attachment, less peritumoral brain edema, and vascular flow voids on neuroimaging, in addition to younger age at diagnosis. Distinguishing between angiomatous meningioma and SFT is much more challenging, as both are highly vascular pathologies. Tumor volume has limited utility in differentiating between SFT and various grades/subtypes of meningioma.

Comparative effectiveness of stent-assisted coiling and Woven EndoBridge embolization for the treatment of unruptured wide-neck bifurcation intracranial aneurysms.

OBJECTIVE: Woven EndoBridge (WEB) intrasaccular flow disruptors and stent-assisted coiling (SAC) are viable endovascular treatment options for wide-neck bifurcation intracranial aneurysms (WNBAs). Data directly comparing these two treatment options are limited. The authors aimed to compare radiographic occlusion rates and complication profiles between patients who received WEB and those who received SAC for WNBAs. METHODS: Retrospective review of a prospectively maintained cerebrovascular procedural database was performed at a single academic medical center between 2017 and 2021. Patients were included if they underwent WEB embolization or SAC of an unruptured WNBA. SAC patients were propensity matched to WEB-embolized patients on the basis of aneurysm morphology. Complete and adequate (complete occlusion or residual neck remnant) occlusion rates at last angiographic follow-up, as well as periprocedural complications, were compared between the two groups. A cost comparison was performed for a typical 5-mm WNBA treated with WEB versus SAC by using manufacturer-suggested retail prices. RESULTS: Thirty-five WEB and 70 SAC patients were included. Aneurysm width, neck size, and dome-to-neck ratio were comparable between groups. Follow-up duration was significantly longer in the SAC group (median [interquartile range] 545 [202-834] days vs 228 [177-494] days, p < 0.001, Mann-Whitney U-test). Complete (66% of WEB patients vs 69% of SAC patients) and adequate (94% WEB vs 91% SAC) occlusion rates were similar between groups at the last available angiographic follow-up (p = 0.744, chi-square test). Complete occlusion rates were comparable on Cox regression analysis after correction for follow-up duration (hazard ratio 1.5, 95% CI 0.8-3.1). Average time to residual aneurysm or neck formation was not statistically different between treatment groups (613 days for SAC patients vs 347 days for WEB patients, p = 0.225, log-rank test). Periprocedural complications trended higher in the SAC group (0% WEB vs 9% SAC, p = 0.175, Fisher exact test), although this finding was not significant. The equipment costs for a typical SAC case were estimated at $18,950, whereas the costs for a typical WEB device case were estimated at $18,630. CONCLUSIONS: Midterm complete and adequate occlusion rates were similar between patients treated with WEB and those treated with SAC. Given these comparable outcomes, there may be equipoise in treatment options for WNBAs.

Magnetic resonance spectroscopy outperforms perfusion in distinguishing between pseudoprogression and disease progression in patients with glioblastoma.

Background: There is a need to establish biomarkers that distinguish between pseudoprogression (PsP) and true tumor progression in patients with glioblastoma (GBM) treated with chemoradiation. Methods: We analyzed magnetic resonance spectroscopic imaging (MRSI) and dynamic susceptibility contrast (DSC) MR perfusion data in patients with GBM with PsP or disease progression after chemoradiation. MRSI metabolites of interest included intratumoral choline (Cho), myo-inositol (mI), glutamate + glutamine (Glx), lactate (Lac), and creatine on the contralateral hemisphere (c-Cr). Student T-tests and area under the ROC curve analyses were used to detect group differences in metabolic ratios and their ability to predict clinical status, respectively. Results: 28 subjects (63 ± 9 years, 19 men) were evaluated. Subjects with true progression (n = 20) had decreased enhancing region mI/c-Cr (P = .011), a marker for more aggressive tumors, compared to those with PsP, which predicted tumor progression (AUC: 0.84 [0.76, 0.92]). Those with true progression had elevated Lac/Glx (P = .0009), a proxy of the Warburg effect, compared to those with PsP which predicted tumor progression (AUC: 0.84 [0.75, 0.92]). Cho/c-Cr did not distinguish between PsP and true tumor progression. Despite rCBV (AUC: 0.70 [0.60, 0.80]) and rCBF (AUC: 0.75 [0.65, 0.84]) being individually predictive of tumor response, they added no additional predictive value when combined with MRSI metabolic markers. Conclusions: Incorporating enhancing lesion MRSI measures of mI/c-Cr and Lac/Glx into brain tumor imaging protocols can distinguish between PsP and true progression and inform patient management decisions.

Magnetic resonance spectroscopic imaging for detecting metabolic changes in glioblastoma after anti-angiogenic therapy-a systematic literature review.

Background: The impact of anti-angiogenic therapy (AAT) on patients with glioblastoma (GBM) is unclear due to a disconnect between radiographic findings and overall survivorship. MR spectroscopy (MRS) can provide clinically relevant information regarding tumor metabolism in response to AAT. This review explores the use of MRS to track metabolic changes in patients with GBM treated with AAT. Methods: We conducted a systematic literature review in accordance with PRISMA guidelines to identify primary research articles that reported metabolic changes in GBMs treated with AAT. Collected variables included single or multi-voxel MRS acquisition parameters, metabolic markers, reported metabolic changes in response to AAT, and survivorship data. Results: Thirty-five articles were retrieved in the initial query. After applying inclusion and exclusion criteria, 11 studies with 262 patients were included for qualitative synthesis with all studies performed using multi-voxel 1H MRS. Two studies utilized 31P MRS. Post-AAT initiation, shorter-term survivors had increased choline (cellular proliferation marker), increased lactate (a hypoxia marker), and decreased levels of the short echo time (TE) marker, myo-inositol (an osmoregulator and gliosis marker). MRS detected metabolic changes as soon as 1-day after AAT, and throughout the course of AAT, to predict survival. There was substantial heterogeneity in the timing of scans, which ranged from 1-day to 6-9 months after AAT initiation. Conclusions: Multi-voxel MRS at intermediate and short TE can serve as a robust prognosticator of outcomes of patients with GBM who are treated with AAT.

Endovascular Management of Arteriovenous Malformation-Associated Intracranial Aneurysms: A Systematic Literature Review.

OBJECTIVE: Intracranial aneurysms are present in up to 18% of arteriovenous malformations (AVMs) and increase the risk of intracranial hemorrhage. No consensus exists on the optimal treatment strategy for AVM-associated aneurysms. The goal of this study was to systematically review endovascular treatment methods of AVM-associated intracranial aneurysms, radiographic outcomes, and periprocedural complications. METHODS: A systematic review was performed in accordance with PRISMA guidelines to identify studies that investigated the use of endovascular treatments for management of patients with AVM-associated aneurysms. Collected variables included aneurysm and AVM location, aneurysm size and characteristics, AVM and aneurysm treatment modality, periprocedural complications, and long-term clinical and radiographic outcomes. RESULTS: Eight studies with 237 patients and 314 AVM-associated intracranial aneurysms were included. Two-hundred and twenty-four aneurysms were flow-related (71.3%), 80 were intranidal (25.5%), and 10 were unrelated (3.2%). Complete occlusion was 56.3% (18/32) for aneurysmal coil embolization and 99% (104/105) for parent vessel sacrifice. Of the 13 aneurysms treated with ethanol sclerotherapy, 8 were successfully obliterated (8/13; 61%) using ethanol sclerotherapy alone and the rest required adjunct endovascular embolization for obliteration of the artery and associated aneurysm. The periprocedural complication rate was approximately 12% and consisted of ischemic symptoms, intracranial hemorrhage, and coiling complications. CONCLUSIONS: Endovascular management options of AVM-associated intracranial aneurysms are limited and mostly comprised primary aneurysmal coil embolization or parent vessel sacrifice using coils or liquid embolics. Embolization strategy depends on factors such as AVM angioarchitecture, rupture status, and adjunct AVM treatments.

Myo-Inositol Levels Measured with MR Spectroscopy Can Help Predict Failure of Antiangiogenic Treatment in Recurrent Glioblastoma.

Background Patients with recurrent glioblastoma (GBM) are often treated with antiangiogenic agents, such as bevacizumab (BEV). Despite therapeutic promise, conventional MRI methods fail to help determine which patients may not benefit from this treatment. Purpose To use MR spectroscopic imaging (MRSI) with intermediate and short echo time to measure corrected myo-inositol (mI)normalized by contralateral creatine (hereafter, mI/c-Cr) in participants with recurrent GBM treated with BEV and to investigate whether such measurements can help predict survivorship before BEV initiation (baseline) and at 1 day, 4 weeks, and 8 weeks thereafter. Materials and Methods In this prospective longitudinal study (2016-2020), spectroscopic data on mI-a glial marker and osmoregulator within the brain-normalized by contralateral creatine in the intratumoral, contralateral, and peritumoral volumes of patients with recurrent GBM were evaluated. Area under the receiver operating characteristic curve (AUC) was calculated for all volumes at baseline and 1 day, 4 weeks, and 8 weeks after treatment to determine the ability of mI/c-Cr to help predict survivorship. Results Twenty-one participants (median age ± standard deviation, 62 years ± 12; 15 men) were evaluated. Lower mI/c-Cr in the tumor before and during BEV treatment was predictive of poor survivorship, with receiver operating characteristic analyses showing an AUC of 0.75 at baseline, 0.87 at 1 day after treatment, and 1 at 8 weeks after. A similar result was observed in contralateral normal-appearing tissue and the peritumoral volume, with shorter-term survivors having lower levels of mI/c-Cr. In the contralateral volume, a lower ratio of mI to creatine (hereafter, mI/Cr) predicted shorter-term survival at baseline and all other time points. Within the peritumoral volume, lower mI/c-Cr levels were predictive of shorter-term survival at baseline (AUC, 0.80), at 1 day after treatment (AUC, 0.93), and at 4 weeks after treatment (AUC, 0.68). Conclusion Lower levels of myo-inositol normalized by contralateral creatine within intratumoral, contralateral, and peritumoral volumes were predictive of poor survivorship and antiangiogenic treatment failure as early as before bevacizumab treatment. Adapting MR spectroscopic imaging alongside conventional MRI modalities conveys critical information regarding the biologic characteristics of tumors to help better treat individuals with recurrent glioblastoma. Clinical trial registration no. NCT02843230 © RSNA, 2021 Online supplemental material is available for this article.