Lacunar Stroke in Cryptococcal Meningitis: Clinical and Radiographic Features.

OBJECTIVE: Cryptococcal meningitis carries a high mortality, and survivors are left with considerable neurologic sequelae and marked disability. We lack a clear understanding of the pathogenesis of neurologic sequelae and description of stroke features in this population. We aim to describe clinical and radiographic features and predictors of stroke in a cohort of patients with cryptococcal meningitis. METHODS: We collected key information on patients diagnosed with cryptococcal meningitis at the University of Colorado Hospital between 2000 and 2018 (n = 42). Of those, 32 had neuroimaging studies available. Bivariate and risk ratio estimates regression models were performed to identify predictors of stroke. RESULTS: We found a 26% ischemic stroke complication rate in individuals with cryptococcal meningitis. Most strokes were acute (75%), lacunar (100%), multiple (88%), bilateral (63%), and involving the basal ganglia (75%). Presence of malignancy (38% versus 8%, P = .085) was higher in stroke in individuals with cryptococcal meningitis, although not statistically significant. Every unit decrease in hemoglobin and serum sodium were predictors for 1.35 and 1.14 times increase in the risk of ischemic stroke, respectively. The presence of hyponatremia carried a RR of 5.7 (95% confidence interval, 1.7-34, P = .005). Cryptococcal meningitis lead to death in 19% of patients and a considerable rate of neurologic sequela among survivors. CONCLUSIONS: Cryptococcal meningitis carries a high risk of lacunar stroke, particularly in the basal ganglia. Cryptococcal meningitis-associated stroke is common and frequently associated with neurologic disability among survivors. We need to understand the possible role of malignancy, anemia, and hyponatremia in the onset of ischemic stroke.

Imaging of Laser Therapy in Epilepsy.

BACKGROUND AND PURPOSE: MR-guided laser interstitial thermal therapy (MRgLITT) is an increasingly popular neuroablative method for the surgical treatment of epilepsy patients. This article intends to demonstrate the utility and pitfalls of imaging in the context of patient care with MRgLITT. MATERIAL AND METHODS: A retrospective review of the medical records and imaging database with six illustrative cases selected to demonstrate the use of imaging throughout patient management with MRgLITT in diverse clinical situations and pathologies. A review of the knowledge in the literature was applied to the relevant points discussed. RESULTS: Imaging findings were described in the setting of laser therapy in nonlesional epilepsy, mesial temporal sclerosis, dual pathology, periventricular nodular heterotopia, and schizencephaly. Discussion of imaging principles, potential pitfalls, as well as its use in the patient work-up and follow-up, is shown. CONCLUSIONS: MRgLITT is an alternative minimally invasive therapy for refractory epilepsy, which is becoming widely sought for. Imaging plays a crucial role prior to, during, and after the procedure.

Cement technique correlates with tuberosity healing in hemiarthroplasty for proximal humeral fracture.

BACKGROUND: Tuberosity healing correlates with clinical outcomes after hemiarthroplasty for 4-part proximal humeral fractures (4PHFs). We seek to examine variables that affect tuberosity healing. METHODS: This was a retrospective comparative study. At 1 year postoperatively, patients who underwent hemiarthroplasty for 4PHFs were divided into 2 groups: those with anatomically healed tuberosities and those with tuberosity nonunion. The primary variables included time between injury and surgery, prosthesis fenestration, cement mantle classification, and both vertical and horizontal tuberosity reduction. Secondary demographic factors included age, gender, osteoporosis status, diabetes status, and smoking status. RESULTS: There were 84 individuals who met the inclusion criteria: 37 (44%) had anatomically healed tuberosities, and 47 (56%) did not. Individuals with anatomic healing had cement near or under the tuberosities 32% of the time, whereas individuals with nonunion or resorption had cement near the tuberosities 66% of the time (P = .002). There was no association between tuberosity healing and fenestration of the humeral stem (P = .84). Anatomic reduction between tuberosities was associated with healing (P <.001), whereas greater tuberosity-to-head height was not (P = .25). There were no significant differences in age, osteoporosis status, smoking status, diabetes status, or time to surgery between groups. Male patients had nearly double the rate of healing (P = .03). DISCUSSION AND CONCLUSION: The classification and effect of cement technique on tuberosity healing have not previously been described. We suggest limiting cementation to a minimum of 5 mm below the level of the tuberosity fracture. The ideal candidate for hemiarthroplasty for a 4PHF is a male patient with anatomic tuberosity reduction and limited use of cement.

Arterial spin labeling: Pathologically proven superiority over conventional MRI for detection of high-grade glioma progression after treatment.

BACKGROUND: Standard of care for high-grade gliomas (HGGs) includes surgical debulking and adjuvant chemotherapy and radiation. Patients under treatment require frequent clinical and imaging monitoring for therapy modulation. Differentiating tumor progression from treatment-related changes can be challenging on conventional MRI, resulting in delayed recognition of tumor progression. Arterial spin labeling (ASL) may be more sensitive for tumor progression. MATERIALS AND METHODS: ASL and associated conventional MR images obtained in patients previously treated for HGGs and before biopsy or re-resection were reviewed by three neuroradiologists who were blinded to the histopathologic results. Regions of interest (ROIs) of greatest perfusion were chosen by consensus, and mirror-image contralateral ROIs were also placed. Sensitivity of ASL for tumor progression was compared with those of contrast-enhanced T1-weighted (T1W-CE) and fluid-attenuated inversion recovery (FLAIR) images using McNemar's test. We tested for an association between cerebral blood flow (CBF) and apparent diffusion correlation (ADC) using a Hotelling-Lawley trace. Finally, we used a Pearson's analysis to test for a correlation between CBF and percentage of tumor within each resection. RESULTS: Twenty-two patients were studied. ASL demonstrated hyperperfusion in all cases with mean CBF ratio 3.37 (±1.71). T1W-CE and FLAIR images were positive in 15 (p = 0.0233) and 16 (p = 0.0412) cases, respectively. There was no association between ADC and CBF (p = 0.687). There was a correlation between CBF and percentage of tumor (p = 0.048). CONCLUSION: ASL may be more sensitive than conventional MR sequences for the detection of tumor progression in patients treated for HGGs.

Postoperative Risk of Hepatic Decompensation after Orthopedic Surgery in Patients with Cirrhosis.

BACKGROUND AND AIMS: Previous studies have shown increased hepatic decompensation in patients with cirrhosis undergoing surgery. However, there are little data available in cirrhotics undergoing orthopedic surgery compared to cirrhotics who did not undergo surgery. The aim of this study was to examine the demographics, comorbid conditions, and clinical factors associated with hepatic decompensation within 90 days in cirrhotics who underwent orthopedic surgery. METHODS: This is a retrospective matched cohort study. Inclusion criteria were cirrhosis diagnosis, age > 18 years, ≥ 6 months continuous health plan membership, and a procedure code for orthopedic surgery. Up to five cirrhotic controls without orthopedic surgery were matched on age, gender, and cirrhosis diagnosis date. Data abstraction was performed for demographics, socioeconomics, clinical, and decompensation data. Chart review was performed for validation. Multivariable analysis estimated relative risk of decompensation. RESULTS: Eight hundred fifty-three orthopedic surgery cases in cirrhotics were matched with 4,263 cirrhotic controls. Among the cases and matched controls, the mean age was 60.5 years, and 52.2% were female. Within 90 days after surgery, cases had more decompensation compared to matched controls (12.8% vs 4.9%). Using multivariable analysis, orthopedic surgery, a 0.5 g/dL decrease in serum albumin, and a 1-unit increase in Charlson Comorbidity Index were associated with a significant increase in decompensation within 90 days of surgery. Diabetes, chronic obstructive pulmonary disease, and chronic kidney disease were seen with increased frequency in cases vs. matched controls. CONCLUSIONS: Cirrhotics who underwent orthopedic surgery had a significant increase in hepatic decompensation within 90 days of surgery compared to matched controls. An incremental decrease in serum albumin and an incremental increase in the Charlson Comorbidity Index were significantly associated with hepatic decompensation after surgery.

The Dotter method revisited: early experience with a novel method of rapid internal carotid artery revascularization in the setting of acute ischemic stroke.

BACKGROUND: Tandem occlusive disease in the setting of acute ischemic stroke involving cervical and cerebral arteries has been associated with poor neurological outcome and poses significant challenges to neurointerventionists. Previously described endovascular methods typically involve carotid revascularization with stent placement prior to or following intracranial thrombectomy. Stent-based approaches, however, require the use of antiplatelet therapy which may increase the risk of hemorrhagic transformation. We describe a novel modified Dotter technique which may be used for carotid revascularization in lieu of stenting. This technique can eliminate the need for antiplatelet therapy, reduce procedure times, and possibly reduce hemorrhagic conversion rates. METHODS: Seven patients presenting between April 2013 and January 2014 were treated with this technique. All patients had carotid stenosis of 65-100% and tandem middle cerebral artery occlusions. National Institutes of Health (NIH) Stroke Scale scores as well as clinical and procedural times were recorded. Pre- and post-Dotter stenosis was measured using the NASCET criteria. Follow-up imaging and clinical data were reviewed. RESULTS: The mean age was 64 years and mean initial NIH Stroke Scale score was 11.7. Mean groin to recanalization time was 26 min. Thrombolysis In Cerebral Infarction grade 2b-3 was achieved in all patients. The mean stenosis was 88% preoperatively and 61% postoperatively. There were no intracranial hemorrhages. The modified Rankin Scale score was 0 in six patients (86%) and 6 in one patient (14%). CONCLUSIONS: The Dotter stroke technique is a feasible and safe alternative to carotid stenting in the setting of acute ischemic stroke and may reduce the risk of hemorrhagic conversion. No re-occlusion occurred during follow-up in patients with post-Dotter stenosis ≤65%.

Initial experience with distal guide catheter placement in the treatment of cerebrovascular disease: clinical safety and efficacy.

BACKGROUND: Advancements in technology have created a current generation of guide catheters that not only provide stable access but also allow navigation of tortuous portions of the carotid siphon facilitating more distal access. Clinical experience since the release of the current generation of guide catheters was reviewed to determine their safety and efficacy. METHODS: Between October 2007 and November 2011, all neurointerventional procedures requiring access to the intracranial arterial circulation performed at our institution were reviewed. Clinical performance and complication rates of current generation guide catheters were compared with conventional guide catheters. RESULTS: 1188 neurointerventional procedures were performed, of which 659 were eligible for this study. When navigating the anterior circulation, intracranial purchase was achieved significantly more often with current generation 0.070 inch and 0.053 inch guide catheters compared with conventional guide catheters. Similarly, current generation 0.070 inch and 0.053 inch catheters navigated at least one sharp 90° turn significantly more often than conventional guide catheters. Guide catheter related complications were encountered in 1.4% of cases with both catheter generations and differences were not significant although more complications were found when guide catheter tip position was cervical rather than intracranial. CONCLUSION: Current generation guide catheters allow distal access with a high rate of success while maintaining a low rate of complications. When intracranial location of the guide catheter was obtained, fewer complications occurred.

Report of two cases of a rare cause of subarachnoid hemorrhage including unusual presentation and an emerging and effective treatment option.

PURPOSE: To report two cases of a rare cause of subarachnoid hemorrhage (SAH), including unusual presentation and an emerging and effective treatment option. CASE REPORTS: Ruptured basilar perforator artery aneurysm is a rare cause of SAH. Catheter angiography in the immediate post hemorrhage period may be unrevealing. We report two cases of ruptured basilar pontine perforator aneurysms. In one of these cases the perforator aneurysm was not apparent on the initial or the 1 week follow-up angiograms. Both patients returned for follow-up angiography 2 months later by which time aneurysmal filling and conspicuity had increased. Both patients were treated solely with two overlapping Neuroform stents. Follow-up angiograms demonstrated complete resolution of the aneurysms in both patients. CONCLUSIONS: Rupture of aneurysms arising from basilar artery perforators is a rare cause of SAH and attention to this area should be part of an interventionist's search pattern. Aneurysms in this area may not be apparent in the immediate post rupture setting and delayed post hemorrhage angiography has a role in detecting this entity. Stent monotherapy may be effective in treating these lesions.

Utilization of CT perfusion patient selection for mechanical thrombectomy irrespective of time: a comparison of functional outcomes and complications.

BACKGROUND: Patient selection for acute ischemic stroke has been largely driven by time-based criteria, although emerging data suggest that image-based criteria may be useful. The purpose of this study was to directly compare outcomes of patients treated within a traditional time window with those treated beyond this benchmark when CT perfusion (CTP) imaging was used as the primary selection tool. METHODS: A prospectively collected database of all patients with acute ischemic stroke who received intra-arterial therapy at the Medical University of South Carolina was retrospectively analyzed, regardless of time from symptom onset. At presentation, CTP maps were qualitatively assessed. Selected patients underwent intra-arterial therapy. Functional outcome according to the modified Rankin scale (mRS) score at about 90 days was documented. RESULTS: 140 patients were included in the study. The median time from symptom onset to groin access was 7.0 h. Overall, 28 patients (20%) had bleeding complications, but only 10 (7.1%) were symptomatic. The average National Institute of Health Stroke Scale (NIHSS) score for patients treated ≤ 7 h from symptom onset was 17.3 and 30.2% had a mRS score of 0-2 at 90 days. Patients treated >7 h from symptom onset had an average NIHSS score of 15.1 and 45.5% achieved a mRS score of 0-2 at 90 days (p=0.104). Patients in the two groups had similar rates of symptomatic intracerebral hemorrhage (8.5% and 5.8%, respectively; p=0.745). CONCLUSIONS: No difference was found in the rates of good functional outcome between patients treated ≤ 7 h and those treated >7 h from symptom onset. These data suggest that imaging-based patient selection is a safe and viable methodology.

Novel use of the pipeline embolization device for reperfusion of the middle cerebral artery post surgical aneurysm clipping.

We describe a case in which elective surgical clipping of an internal carotid artery terminus aneurysm resulted in compromised flow through the ipsilateral middle cerebral artery (MCA). Reperfusion was salvaged the following day with novel use of the pipeline embolization device to buttress open the MCA. We believe that mechanical properties unique to the pipeline device facilitated the success of the procedure.

Transient cranial neuropathies as sequelae of Onyx embolization of arteriovenous shunt lesions near the skull base: possible axonotmetic traction injuries.

INTRODUCTION: Transarterial embolization with Onyx is a relatively safe and increasingly common method of treating cranial dural arteriovenous fistulas (DAVF) and arteriovenous malformations (AVM). Cranial neuropathy resulting from this procedure has been reported. CASE REPORTS: Three case histories are presented in two patients treated for a DAVF and an AVM near the skull base with heavily parasitized supply from external carotid artery branches. Transarterial embolization resulted in transient cranial neuropathies including two cases of lower facial nerve palsy and one case of trigeminal nerve mandibular segment (V3) neuralgia which resolved spontaneously over a few months. Treatment of the DAVF and AVM was otherwise successful. DISCUSSION: The most common cranial neuropathies following transarterial Onyx embolization procedures are facial nerve palsy and V3 neuralgia. The middle meningeal and internal maxillary arteries are common conduits used in dural-based and facial arteriovenous shunt lesions and are in proximity to the facial nerve and maxillary segment of the trigeminal nerve as they exit the skull base. Based on their relative frequency and anatomic proximity, it is surmised that these facial neuropathies are traction-type injuries related to microcatheter extraction from the Onyx cast. CONCLUSIONS: Cranial neuropathies, specifically facial nerve palsy and V3 neuralgia, following transarterial Onyx embolizations are probably axonotmetic traction injuries related to microcatheter extraction. These appear to be self-limiting and resolve over a few months.

Nicotine effects on default mode network during resting state.

RATIONALE: The default mode network (DMN), one of several resting-state networks (RSN) in the brain, is thought to be involved in self-referential thought, awareness, and episodic memories. Nicotine improves cognitive performance, in part by improving attention. Nicotinic agonists have been shown to decrease activity in regions within DMN and increase activity in regions involved in visual attention during effortful processing of external stimuli. It is unknown if these pharmacological effects also occur in the absence of effortful processing. OBJECTIVES: This study aims to determine if nicotine suppresses activity in default mode and enhances activity in extra-striate RSNs in the absence of an external visual task. METHODS: Within-subject, single-blinded, counterbalanced study of 19 non-smoking subjects who had resting functional MRI scans after 7 mg nicotine or placebo patch. Group independent component analysis was performed. The DMN component was identified by spatial correlation with a reference DMN mask. A visual attention component was identified by spatial correlation with an extra-striate mask. Analyses were conducted using statistical parametric mapping. RESULTS: Nicotine was associated with decreased activity in regions within the DMN and increased activity in extra-striate regions. CONCLUSIONS: Suppression of DMN and enhancement of extra-striate resting-state activity in the absence of visual stimuli or effortful processing suggest that nicotine's cognitive effects may involve a shift in activity from networks that process internal to those that process external information. This is a potential mechanism by which cholinergic agonists may have a beneficial effect in diseases associated with altered resting-state activity.