Time to Steroid Independence After Laser Interstitial Thermal Therapy vs Medical Management for Treatment of Biopsy-Proven Radiation Necrosis Secondary to Stereotactic Radiosurgery for Brain Metastasis.

BACKGROUND: Radiation necrosis (RN) after stereotactic radiosurgery (SRS) for brain metastases (BM) can result in significant morbidity, compounded by the effects of extended steroid therapy. Laser interstitial thermal therapy (LITT) is a minimally invasive procedure that can offer definitive treatment for RN while potentially obviating the need for prolonged steroid use. OBJECTIVE: To compare LITT vs medical management (MM) in the treatment of RN. METHODS: A multicenter, retrospective study was performed of SRS-treated patients with BM who developed biopsy-proven RN and were treated with LITT or MM. Clinical outcome data were compared by treatment modality. RESULTS: Seventy-two patients met criteria with a median follow-up of 10.0 months (4.2-25.1), and 57 patients (79%) underwent LITT. Four MM (27%) and 3 LITT patients (5%) demonstrated radiographic progression (P = .031) at a median of 5.3 and 4.0 months (P = .40). There was no significant difference in overall survival (LITT median of 15.2 vs 11.6 months, P = .60) or freedom from local progression (13.6 vs 7.06 months, P = .40). Patients stopped steroid therapy earlier in the LITT cohort at a median of 37 days compared with 245 days (P < .001). When controlled for follow-up duration, patients treated with LITT were 3 times more likely to be weaned off steroids before the study end point (P = .003). CONCLUSION: These data suggest that LITT for treatment of biopsy-proven RN after SRS for BM significantly decreases time to steroid independence. Prospective trials should be designed to further validate the utility of LITT for RN and its impact on steroid-induced morbidity.

Inferolateral thalamic ischemia secondary to PCA P2 perforator occlusion mimics MCA stroke syndrome.

Paramedian thalamic strokes following occlusion of the posterior medial (paramedian) thalamic perforators have been previously described in great detail. However, the stroke syndrome associated with occlusion of posterior lateral (inferolateral) thalamic perforators is less commonly known. We present an illustrative case of an inferolateral thalamic perforator stroke mimicking a middle cerebral artery (MCA) syndrome and provide a review of the literature. A 62-year-old male presented with dysarthria, contralateral hemisensory loss, and contralateral weakness, concerning for possible MCA stroke. However, close examination revealed the hemiparesis to be ataxic in nature. Imaging revealed a left PCA P2 segment occlusion and lacunar infarction of the ventral lateral (VL) and ventral posterior (VP) thalamus, the main thalamic destination of cerebellar and sensory pathways. The case is unique because the P1 segment and posterior communicating artery (Pcom) remained patent, resulting in selective occlusion of only the posterior lateral (inferolateral) thalamic perforators at the P2 level. Acute loss of the posterior lateral (inferolateral) thalamic perforators at the proximal P2 segment results in a ventral lateral and ventral posterior thalamic stroke characterized by contralateral hemisensory loss, contralateral ataxic hemiparesis, and dysarthria. It is important to recognize the inferolateral thalamic stroke syndrome, as it may be mistaken clinically for an MCA occlusion. The benefit of mechanical thrombectomy for this type of stroke is not well established and should be considered carefully.

Masson's tumor presenting as a left frontal intraparenchymal hemorrhage resulting in severe expressive aphasia during pregnancy: case report.

Intravascular papillary endothelial hyperplasia (IPEH), commonly known as Masson's tumor, is a benign lesion that manifests as an excessive proliferation of endothelial cells within a vessel wall. IPEH is extremely rare in the brain, with only 36 intracranial cases previously described in the literature. It is commonly mistaken for more malignant pathologies, such as angiosarcoma. Careful histopathological examination is required for diagnosis, as no clinical or radiographic features are characteristic of this lesion. In this first published case of intracranial IPEH presenting during pregnancy, the authors describe a 32-year-old female with a left frontal intraparenchymal hemorrhage resulting in complete expressive aphasia at 28 weeks 6 days' gestation. An MRI scan obtained at a local hospital demonstrated an area of enhancement within the hemorrhage. The patient underwent a left frontoparietal craniotomy for hematoma evacuation and gross-total resection (GTR) of an underlying hemorrhagic mass at 29 weeks' gestation. This case illustrates the importance of multidisciplinary patient care and the feasibility of intervention in the early third trimester with subsequent term delivery. While GTR of IPEH is typically curative, the decision to proceed with surgical treatment of any intracranial lesion in pregnancy must balance maternal stability, gestational age, and suspected pathology.

CSF volume provocation maneuvers during lumbar puncture as a possible predictive tool for diagnosing spontaneous intracranial hypotension.

OBJECTIVES: Spontaneous intracranial hypotension (SIH) is a pathologic state of low CSF volume caused by a CSF to venous fistula or CSF leak. It is diagnosed based on symptoms, imaging, and CSF pressure but is often a diagnostic challenge because no single test is highly sensitive. Physician-induced changes in CSF volume may result in changes in patient symptoms, as has been shown with idiopathic intracranial hypertension (IIH). The purpose of this study is to determine the sensitivity of CSF volume provocation maneuvers in the diagnosis of SIH. PATIENTS AND METHODS: We reviewed consecutive patients that underwent lumbar puncture from January 2015 to January 2017. Patients were included if they met ICHD3 criteria for SIH and CSF volume provocation maneuvers were performed. Cases were considered concordant if there was improvement of symptoms with addition of CSF. RESULTS: 1084 patients underwent 2250 CT-guided lumbar punctures from January 2015 to January 2017. 92 patients with SIH were identified and 62 of these patients underwent CSF volume provocation maneuvers. 58% (36/62) had concordant lumbar puncture encounters with symptom improvement upon addition of artificial CSF. CONCLUSION: CSF volume provocation maneuvers demonstrate 58% sensitivity for identifying patients with SIH, better than those reported for CSF opening pressure and myelography. A positive symptomatic response to CSF volume provocation maneuvers was independent of the other objective tests used for SIH and may aid in the often-challenging diagnostic workup of these patients. Future prospective case-controlled studies are needed.

Endovascular repair of an acute symptomatic carotid artery dissection through the false dissecting carotid lumen.

A 48-year-old woman presented with an acute ischemic stroke (National Institutes of Health Stroke Scale (NIHSS) 21) six hours after symptom onset. Workup revealed a left cervical internal carotid artery (ICA) occlusive dissection, which was emergently reconstructed with a flow-diverting stent. A routine Duplex scan one hour later suggested reocclusion of the ICA, confirmed by angiography. The true lumen of the ICA could not be accessed and therefore the "false lumen" of the ICA dissection was entered proximally. The true lumen and ultimately the flow-diverting stent were accessed via the false lumen. In analogy to the subintimal arterial flossing with antegrade-retrograde intervention technique described for peripheral vascular disease, several stents were placed in telescoping fashion from the true common carotid lumen through the "false dissecting" lumen of the proximal ICA into the distal true lumen. The stent construct remained patent, and the patient recovered clinically to an NIHSS of 1.

Treatment of direct carotid-cavernous fistulas with flow diversion - does it work?

Direct carotid-cavernous fistulas (CCFs) are high flow lesions that can be challenging to treat. A number of recent reports suggest that flow diversion may be a viable treatment option. We present a case of a post-traumatic CCF successfully treated with flow diversion and provide a review of the literature. Our results suggest that flow diversion is a potentially effective treatment option for CCFs and is most successful when used as an adjunctive therapy.

Infundibular Dilations and Subarachnoid Hemorrhage: to Treat or Not to Treat?

BACKGROUND: Infundibular dilations are funnel-shaped widenings at the origin of a cerebral artery, most commonly the posterior communicating artery. Controversy exists as to whether an infundibulum represents a normal anatomic variant or a lesion with the potential for rupture and subarachnoid hemorrhage (SAH). METHODS: We reviewed all reported cases of infundibular dilations and SAH in the world literature and present an illustrative case. RESULTS: Most infundibula in the context of SAH were associated with an aneurysm either on or near an infundibulum. However, there have been 7 reports in which the infundibulum could have been the primary site of rupture and no associated aneurysm was identified. Close review reveals significant limitations of those 7 reports. CONCLUSIONS: The literature, and our own experience, do not support the treatment of infundibula, even in SAH patients. Treatment should be directed toward an associated aneurysm, not the infundibulum.

Onyx embolization of a pial AV fistula with a giant venous varix using a flow-directed Scepter balloon catheter: Technical note.

BACKGROUND AND IMPORTANCE: Pial arteriovenous fistulas (AVFs) of the brain are treacherous lesions that can be challenging to treat because of high risk of hemorrhage. We report on a rare case of a pial AVF with a giant venous varix as a draining vein treated successfully with flow-directed balloon-assisted Onyx embolization. CLINICAL PRESENTATION: A 56-year-old female with headaches underwent brain magnetic resonance imaging, which demonstrated a 4 cm aneurysmal malformation in the right temporal lobe. A diagnostic cerebral angiogram demonstrated a right temporal pial AVF fed by an enlarged right posterior cerebral artery with drainage into a giant venous varix. Onyx embolization was curative using a flow-directed Scepter balloon catheter. CONCLUSION: Flow-directed balloon-assisted Onyx embolization can be highly successful for the curative embolization of pial AVFs. Balloon application changes the nature of the lesion from high-flow-high risk to no-flow-low-risk. Using a flow-directed technique with balloon microcatheters may help minimize the risk of intracranial vascular injury.

Improved Quality of Thyroid Ultrasound Reports After Implementation of the ACR Thyroid Imaging Reporting and Data System Nodule Lexicon and Risk Stratification System.

PURPOSE: The aim of this study was to compare the description and management recommendations for thyroid nodules before and after implementing a structured reporting template based on the ACR Thyroid Imaging Reporting and Data System (TI-RADS). METHODS: Thyroid ultrasound reports for seven private practice radiologists were analyzed in three phases. In phase 1, radiologists dictated in a free-text format. In phase 2, they used a structured reporting template based on the ACR TI-RADS lexicon, but without the ACR TI-RADS recommendations for nodule management. In phase 3, ACR TI-RADS management recommendations were added. The most suspicious thyroid nodule in each report was analyzed for size, features, and management recommendations in all three phases. RESULTS: Seventy-one thyroid ultrasound reports were reviewed for each phase, for a total of 213 reports. In phase 1, reports did not describe the features of the majority of nodules. In particular, shape and margin were not reported for 100% and 92% of nodules, respectively. Ninety-six percent to 100% of nodules had descriptions of all five features in phases 2 and 3. The number of nodules without management recommendations was 34% in phase 1 and 31% in phase 2. It decreased to 6% in phase 3 (P < .0005). CONCLUSIONS: Implementing an ACR TI-RADS structured reporting template improved the quality of thyroid ultrasound reports in two key ways. A structured reporting template led to better description of features that are predictive of malignancy. The use of ACR TI-RADS management guidelines substantially improved the number of reports with definitive management recommendations.

Early infection risk with primary versus staged Hemodialysis Reliable Outflow (HeRO) graft implantation.

OBJECTIVE: This study evaluated whether the use of a staged Hemodialysis Reliable Outflow (HeRO; Merit Medical, South Jordan, Utah) implantation strategy incurs increased early infection risk compared with conventional primary HeRO implantation. METHODS: A retrospective review was performed of 192 hemodialysis patients who underwent HeRO graft implantation: 105 patients underwent primary HeRO implantation in the operating room, and 87 underwent a staged implantation where a previously inserted tunneled central venous catheter was used for guidewire access for the venous outflow component. Within the staged implantation group, 32 were performed via an existing tunneled hemodialysis catheter (incidentally staged), and 55 were performed via a tunneled catheter inserted across a central venous occlusion in an interventional radiology suite specifically for HeRO implantation (intentionally staged). Early infection was defined as episodes of bacteremia or HeRO infection requiring resection ≤30 days of HeRO implantation. RESULTS: For staged HeRO implantations, the median interval between tunneled catheter insertion and conversion to a HeRO graft was 42 days. The overall HeRO-related infection rate ≤30 days of implantation was 8.6% for primary HeRO implantation and 2.3% for staged implantations (P = .12). The rates of early bacteremia and HeRO resection requiring surgical resection were not significantly different between groups (P = .19 and P = .065, respectively), nor were age, gender, laterality, anastomosis to an existing arteriovenous access, human immunodeficiency virus status, diabetes, steroids, chemotherapy, body mass index, or graft location. None of the patient variables, techniques, or graft-related variables correlated significantly with the early infection rate. CONCLUSIONS: The staged HeRO implantation strategy did not result in an increased early infection risk compared with conventional primary implantation and is thus a reasonable strategy for HeRO insertion in hemodialysis patients with complex central venous disease.

Massive gas gangrene secondary to occult colon carcinoma.

Gas gangrene is a rare but often fatal soft-tissue infection. Because it is uncommon and the classic symptom of crepitus does not appear until the infection is advanced, prompt diagnosis requires a high index of suspicion. We present a case report of a middle-aged man who presented with acute onset lower-extremity pain that was initially thought to be due to deep vein thrombosis. After undergoing workup for pulmonary embolism, he was found to have massive gas gangrene of the lower extremity secondary to an occult colon adenocarcinoma and died within hours of presentation from multisystem organ failure.

Effectiveness of Transarterial Embolization of Hepatocellular Carcinoma as a Bridge to Transplantation.

PURPOSE: To assess the effectiveness of bland transarterial embolization of hepatocellular carcinoma (HCC) as a "bridge" to transplantation. MATERIALS AND METHODS: In this retrospective study, 117 patients with HCC that met Milan criteria underwent bland embolization as their initial and sole therapy for treatment of HCC (88 men and 29 women; mean age, 60.4 y; range, 35-88 y). Subsequent postembolization contrast-enhanced computed tomography or magnetic resonance imaging studies were reviewed to determine whether Milan criteria were met in an intent-to-transplant analysis. Freedom from progression beyond Milan criteria and survival were calculated by Kaplan-Meier technique. Predictors of progression and survival were also assessed. RESULTS: After embolization, 87% and 78% of patients' disease still met Milan criteria at 6 and 12 months, respectively. The median time until disease progression beyond Milan criteria was 22.6 months (95% confidence interval, 16.2-29 mo). α-Fetoprotein levels, number of lesions, United Network for Organ Sharing stage, Model for End-stage Liver Disease score, and cirrhosis etiology did not correlate significantly with stability within Milan criteria. A total of 34 patients (29%) underwent eventual liver transplantation at a median of 3.3 months (range, 0.5-20.9 mo). Liver transplantation was a significant independent predictor of longer survival (6.9 y vs 2.6 y; P < .001). The major complication rate within 30 days of embolization was 2.6%, including one mortality. CONCLUSIONS: Bland transarterial embolization as a bridging strategy to maintain HCC within Milan criteria was successful in 78% of patients at 1 year, which compares favorably with other locoregional embolotherapies.

Development and utilization of a web-based application as a robust radiology teaching tool (radstax) for medical student anatomy teaching.

Rationale and Objectives: The primary role of radiology in the preclinical setting is the use of imaging to improve students' understanding of anatomy. Many currently available Web-based anatomy programs include either suboptimal or overwhelming levels of detail for medical students.Our objective was to develop a user-friendly software program that anatomy instructors can completely tailor to match the desired level of detail for their curriculum, meets the unique needs of the first- and the second-year medical students, and is compatible with most Internet browsers and tablets.Materials and Methods: RadStax is a Web-based application developed using free, open-source, ubiquitous software. RadStax was first introduced as an interactive resource for independent study and later incorporated into lectures. First- and second-year medical students were surveyed for quantitative feedback regarding their experience.Results: RadStax was successfully introduced into our medical school curriculum. It allows the creation of learning modules with labeled multiplanar (MPR) image sets, basic anatomic information, and a self-assessment feature. The program received overwhelmingly positive feedback from students. Of 115 students surveyed, 87.0% found it highly effective as a study tool and 85.2% reported high user satisfaction with the program.Conclusions: RadStax is a novel application for instructors wishing to create an atlas of labeled MPR radiologic studies tailored to meet the specific needs their curriculum. Simple and focused, it provides an interactive experience for students similar to the practice of radiologists.This program is a robust anatomy teaching tool that effectively aids in educating the preclinical medical student.

Surveillance after resection of vestibular schwannoma: measurement techniques and predictors of growth.

OBJECTIVES: To compare different methods of measuring tumor growth after resection of vestibular schwannoma and to identify predictors of growth. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center, inpatient surgery with ambulatory follow-up. PATIENTS: All patients who underwent vestibular schwannoma resection by the senior author from September 1991 to April 2012 and had two or more postoperative MRI scans. INTERVENTIONS: Vestibular schwannoma resection. Measurement of tumor size and enhancement pattern on postoperative magnetic resonance imaging scans. MAIN OUTCOME MEASURES: Tumor size as measured in one (linear), two (planar), and three (volumetric) dimensions using standard radiology workstation tools versus time elapsed since surgical resection. RESULTS: Eighty-eight patients were included with mean follow-up of 3.9 years. Linear measurement of tumor size was found to have modest correlation with planar and volumetric measurements. Excellent correlation was found between the planar and volumetric methods. Nodular enhancement increased risk for tumor growth (OR 6.25, p = 0.03 on planar analysis). If there was growth, tumors with nodular enhancement typically showed increase in size beginning 2 years postoperatively, whereas those with linear or no enhancement were typically stable in size through 5 years. Younger age and larger preoperative tumor size were also risk factors for growth (OR 0.9/p = 0.01 and OR 1.09/p = 0.02). CONCLUSION: Simple planar measurement is an efficient method that correlates well with the more time-consuming volumetric method. The major risk factor for tumor growth is nodular enhancement on a baseline scan, a finding that warrants annual MRI beginning 2 years postoperatively. Younger age and larger preoperative size minimally increased risk of growth.