Fellows’ Journal Club

White Matter Injury and General Movements in High-Risk Preterm Infants

Fellows’ Journal Club

Cerebral palsy has been predicted by analysis of spontaneous movements in the infant termed “General Movement Assessment.” The authors evaluated the utility of General Movement Assessment in predicting adverse cognitive, language, and motor outcomes in very preterm infants and attempted to identify brain imaging markers associated with both adverse outcomes and aberrant general movements in 47 preterm infants using MRI volumetric analysis and DTI. Nine infants had aberrant general movements and were more likely to have adverse neurodevelopmental outcomes, compared with infants with normal movements. In infants with aberrant movements, Tract-Based Spatial Statistics analysis identified significantly lower fractional anisotropy in widespread WM tracts. They conclude that aberrant general movements at 10–15 weeks’ postterm are associated with adverse neurodevelopmental outcomes and specific white matter microstructure abnormalities for cognitive, language, and motor delays.

Abstract

Figure 1 from paper
Differences in white matter at term-equivalent age between infants with normal and aberrant fidgety movements at 10–15 weeks. Mean FA skeleton, in green, is overlaid on the mean FA map. Superimposed are pseudocolored voxels having significantly greater anisotropy in infants with normal than in infants with aberrant fidgety movements. Color bar shows the range of P values represented by the pseudocolors. Significantly higher regions of FA can be observed in the splenium (ccs) and genu (ccg) of the corpus callosum, inferior (ilf) and superior longitudinal fasciculus (slf), fronto-occipital fasciculus (fof), anterior (alic) and posterior (plic) internal capsule, corona radiata (cr), cerebellar peduncles (cp), and fornix/stria terminalis (fx/st). Z represents the MR imaging axial section coordinates (zero is the center of the anterior commissure).

BACKGROUND AND PURPOSE

Very preterm infants (birth weight, <1500 g) are at increased risk of cognitive and motor impairment, including cerebral palsy. These adverse neurodevelopmental outcomes are associated with white matter abnormalities on MR imaging at term-equivalent age. Cerebral palsy has been

Endovascular Therapy of M2 Occlusion in IMS III: Role of M2 Segment Definition and Location on Clinical and Revascularization Outcomes

Fellows’ Journal Club

The authors reviewed the impact of revascularization on clinical outcomes in 83 patients with M2 occlusions in the Interventional Management of Stroke III trial according to specific M1–M2 segment anatomic features. AnmRS 0–2 outcome was associated with reperfusion for M2 trunk (n = 9) or M2 division (n = 42) occlusions, but not for M2 branch occlusions (n = 28). Of the 83 participants with M2 occlusion who underwent endovascular therapy, 41.0% achieved mRS 0–2 at 90 days, including 46.6% with modified TICI 2–3 reperfusion compared with 26.1% with modified TICI 0–1 reperfusion. They conclude that mRS 0–2 at 90 days was dependent on reperfusion for M2 trunk but not for M2 branch occlusions in IMS III.

Abstract

Figure 1 from paper
A, Right M1 trunk gives rise to the ATA with the posterior temporal branch filling on microcatheter injection. B, Lateral view baseline common carotid arteriogram confirms mid- and posterior temporal lobe cortical supply from the patent posterior temporal artery.

BACKGROUND AND PURPOSE

Uncertainty persists regarding the safety and efficacy of endovascular therapy of M2 occlusions following IV tPA. We reviewed the impact of revascularization on clinical outcomes in 83 patients with M2 occlusions in the Interventional Management of Stroke III trial according to specific M1-M2 segment anatomic features.

MATERIALS AND METHODS

Perfusion of any M2 branch distinguished M2-versus-M1 occlusion. Prespecified modified TICI and arterial occlusive lesion revascularization and clinical mRS 0–2 end points at 90 days for endovascular therapy–treated M2 occlusions were analyzed. Post hoc analyses of the relationship of outcomes to multiple baseline angiographic M2 and M1 subgroup characteristics were performed.

RESULTS

Of 83 participants with M2 occlusion who underwent endovascular therapy, 41.0% achieved mRS 0–2 at 90 days, including 46.6% with modified TICI 2–3 reperfusion compared with 26.1% with modified TICI 0–1 reperfusion (risk

Fellows’ Journal Club Recap: Quantitative MRI for automated CSF measurements in hydrocephalus evaluation

Please check out the accompanying podcast of this blog post (discussion of this article begins at 15:07)

Current evaluation of idiopathic normal pressure hydrocephalus (NPH) depends predominantly on clinical examination, although there are some imaging features, including enlarged lateral ventricles, bowing of the corpus callosum, and enlargement of the sylvian fissures out of proportion to the other cerebrospinal fluid (CSF) spaces. However, these imaging features are largely subjective, depending heavily on the opinion of the interpreting physician.

In this paper, the authors sought to improve evaluation of idiopathic normal pressure hydrocephalus by developing an automated method for calculating CSF volumes within the calvarium, including volume in the lateral ventricles, total intracranial CSF volume, and brain parenchymal fraction. They compared this to manual segmentation and measured volumes in patients being evaluated for NPH both before and after a large volume lumbar puncture.

The results demonstrate that the method was useful for measuring CSF volumes, with good correlation between the automatic method and manual segmentation. Furthermore, the ventricular volume decreased after the large volume lumbar puncture, with the difference most pronounced 30 minutes after the procedure and gradually returning towards baseline over a 24 hour period. The method was also useful for calculating brain parenchymal fraction, which cannot be easily calculated manually.

These findings are interesting for several reasons. First, it is valuable to know that the automated method is reliable when compared to manual measurements and can be used to see how much change there is in the CSF volumes of patients being evaluated for normal pressure hydrocephalus. It is a natural extension of this study to see what the clinical outcomes were for these patients, and potentially know if there was a difference in patient that were ultimately diagnosed with NPH. Ideally, these values could potentially predict which …

Intracranial Arteriovenous Shunting: Detection with Arterial Spin-Labeling and Susceptibility-Weighted Imaging Combined

Fellows’ Journal Club

Ninety-two consecutive patients with a known (n = 24) or suspected arteriovenous shunting (n = 68) underwent DSA and brain MR imaging, including arterial spin-labeling/SWI and conventional angiographic MR imaging. DSA showed arteriovenous shunting in 63 of the 92 patients. Interobserver agreement was excellent. In 5 patients, arterial spin-labeling/SWI correctly detected arteriovenous shunting, while the conventional angiographic MR imaging did not. The authors conclude that the combined use of arterial spin-labeling and SWI may be an alternative to contrast-enhanced MRA for the detection of intracranial arteriovenous shunting.

Abstract

Figure 3 from paper
A 60-year-old patient with a right paracentral AVM. ASL raw data (A) demonstrates a strong hypersignal at the anterior part of the right paracentral region (A, arrow). The slight venous hypersignal related to AVS was initially missed by the blinded readers by using SWI alone (B, arrowhead) but was correctly identified by using ASL and SWI combined (C, ASL/SWI merged image, arrow). Findings of time-resolved 4D contrast-enhanced MRA (D) were considered negative by the blinded readers. DSA reveals a small pial AVM in the right paracentral region (E, arrow).

BACKGROUND AND PURPOSE

Arterial spin-labeling and susceptibility-weighted imaging are 2 MR imaging techniques that do not require gadolinium. The study aimed to assess the accuracy of arterial spin-labeling and SWI combined for detecting intracranial arteriovenous shunting in comparison with conventional MR imaging.

MATERIALS AND METHODS

Ninety-two consecutive patients with a known (n = 24) or suspected arteriovenous shunting (n = 68) underwent digital subtraction angiography and brain MR imaging, including arterial spin-labeling/SWI and conventional angiographic MR imaging (3D TOF, 4D time-resolved, and 3D contrast-enhanced MRA). Arterial spin-labeling/SWI and conventional MR imaging were reviewed separately in a randomized order by 2 blinded radiologists who judged the presence or absence of arteriovenous shunting. The accuracy of arterial spin-labeling/SWI for the detection of

CT and MR Imaging in the Diagnosis of Scleritis

Fellows’ Journal Club

Scleritis is a rare vision-threatening condition that can occur isolated or in association with other orbital abnormalities and whose etiology is typically inflammatory/noninfectious, either idiopathic or in the context of systemic disease. The authors analyzed 11 cases of scleritis in which CT and/or MR imaging were performed during the active phase of disease and assessed the diagnostic utility of these techniques. The most important imaging findings of scleritis were scleral enhancement, scleral thickening, and focal periscleral cellulitis. MR imaging is the recommended imaging technique.

Summary

Figure 1 from paper
Asynchronous IOID with scleritis. A, CECT depicts outward, eccentric thickening and enhancement of the right globe wall with focal periscleral cellulitis (black arrow), compatible with posterior scleritis. There is associated pre- and postseptal cellulitis (white arrow) and proptosis. B, CECT 18 months after examination (A) shows almost identical findings in the left orbit. Black and white arrows point to the scleritis and cellulitis, respectively. Notice the complete resolution of the alterations of the right orbit. Also, notice involvement of the tendon of the lateral rectus anteriorly (dashed arrow).

Scleritis is a rare, underdiagnosed vision-threatening condition that can occur isolated or in association with other orbital abnormalities. The etiology of scleritis is mainly inflammatory noninfectious, either idiopathic or in the context of systemic disease. Ultrasonography remains the criterion standard in diagnostic imaging of this condition but might prove insufficient, and studies on the diagnostic value of CT and MR imaging are lacking. We retrospectively analyzed 11 cases of scleritis in which CT and/or MR imaging were performed during the active phase of disease and assessed the diagnostic utility of these techniques. The most important imaging findings of scleritis were scleral enhancement, scleral thickening, and focal periscleral cellulitis. MR imaging is the recommended imaging technique, though posterior scleritis also can be accurately diagnosed on

Yield of Repeat 3D Angiography in Patients with Aneurysmal-Type Subarachnoid Hemorrhage

Fellows’ Journal Club

The purpose of this study was to evaluate the yield of repeat 3D rotational angiography in patients with aneurysmal-type SAH with negative initial 3D rotational angiography findings. Between March 2013 andJanuary 2016, 292 patients with SAH and an aneurysmal bleeding pattern were admitted, with 30 having initial negative 3D rotational angiography findings within 24 hours. These patients underwent a second 3D rotational angiography after 7–10 days. In 8/30 patients (over 26%) with initial negative 3D rotational angiography findings, a ruptured aneurysm wasfound on repeat 3D rotational angiography. The investigators conclude that repeat 3D rotational angiography is mandatory in patients with initial 3D rotational angiography findings negative for aneurysmal-type SAH.

Abstract

Figure 2 from paper
A 62-year-old woman with initial negative findings on 3DRA. A, 3DRA within 24 hours after SAH shows no aneurysm. B, Repeat 3DRA after 10 days shows an 8-mm supraclinoid internal artery dissecting aneurysm.

BACKGROUND AND PURPOSE

Aneurysmal-type subarachnoid hemorrhage is a serious disease with high morbidity and mortality. When no aneurysm is found, the patient remains at risk for rebleeding. Negative findings for SAH on angiography range from 2% to 24%. Most previous studies were based on conventional 2D imaging. 3D rotational angiography depicts more aneurysms than 2D angiography. The purpose of this study was to evaluate the yield of repeat 3D rotational angiography in patients with aneurysmal-type SAH with negative initial 3D rotational angiography findings and to classify the initial occult aneurysms.

MATERIALS AND METHODS

Between March 2013 and January 2016, 292 patients with SAH and an aneurysmal bleeding pattern were admitted. Of these 292 patients, 30 (10.3%; 95% CI, 7.3%–14.3%) had initial negative 3D rotational angiography findings within 24 hours. These patients underwent a second 3D rotational angiography after 7–10 days.

RESULTS

In 8 of 30 patients (26.7%; 95% CI, 14.0%–44.7%) with initial negative 3D

Comparison of High-Resolution MR Imaging and Digital Subtraction Angiography for the Characterization and Diagnosis of Intracranial Artery Disease

Fellows’ Journal Club

Thirty-seven patients who had undergone both high-resolution MR imaging and DSA for intracranial artery disease were evaluated. The degree of stenosis and the minimal luminal diameter were independently measured by 2 observers on both DSA and high-resolution MR imaging, and the results were compared. The 2 observers independently diagnosed intracranial artery diseases on DSA and high-resolution MR imaging. High-resolution MR imaging showed moderate-to-excellent agreement and significant correlations with DSA on the degree of stenosis and minimal luminal diameter. The authors conclude that high-resolution MR imaging may be an imaging method comparable with DSA for the characterization and diagnosis of various intracranial artery diseases.

Abstract

Figure 1 from paper
Measurements of the degree of stenosis and minimal luminal diameter in both DSA and HR-MR. The degree of stenosis is 73.9% on HR-MR (normal luminal diameter, 3.18 mm; minimal luminal diameter, 0.83 mm) and 72.7% on DSA (normal luminal diameter, 2.86 mm; minimal luminal diameter, 0.78 mm).

BACKGROUND AND PURPOSE

High-resolution MR imaging has recently been introduced as a promising diagnostic modality in intracranial artery disease. Our aim was to compare high-resolution MR imaging with digital subtraction angiography for the characterization and diagnosis of various intracranial artery diseases.

MATERIALS AND METHODS

Thirty-seven patients who had undergone both high-resolution MR imaging and DSA for intracranial artery disease were enrolled in our study (August 2011 to April 2014). The time interval between the high-resolution MR imaging and DSA was within 1 month. The degree of stenosis and the minimal luminal diameter were independently measured by 2 observers in both DSA and high-resolution MR imaging, and the results were compared. Two observers independently diagnosed intracranial artery diseases on DSA and high-resolution MR imaging. The time interval between the diagnoses on DSA and high-resolution MR imaging was 2 weeks. Interobserver diagnostic agreement for each technique and intermodality

Cervical Spinal Cord DTI Is Improved by Reduced FOV with Specific Balance between the Number of Diffusion Gradient Directions and Averages

Fellows’ Journal Club

The authors evaluated multiple parameters of reduced-FOV DTI to optimize image quality. Fifteen healthy individuals underwent cervical spinal cord 3T MRI, including an anatomic 3D Multi-Echo Recombined Gradient Echo, high-resolution full-FOV DTI with a NEX of 3 and 20 diffusion gradient directions, and 5 sets of reduced-FOV DTIs differently balanced in terms of NEX/number of diffusion gradient directions. Qualitatively, reduced-FOV DTI sequences with a NEX of >5 were significantly better rated than the full-FOV DTI and the reduced-FOV DTI with low NEX (N=3) and a high number of diffusion gradient directions (D=20). Quantitatively, the best trade-off was reached by the reduced-FOV DTI with a NEX of 9 and 9 diffusion gradient directions. They conclude that the best compromise was obtained with a NEX of 9 and 9 diffusion gradient directions, which emphasizes the need for increasing the NEX at the expense of the number of diffusion gradient directions for spinal cord DTI, unlike brain imaging.

Abstract

Figure 2 from paper
Examples of MR images available for qualitative analysis. All the images came from the same subject. Cervical levels are located on 3D T2-MERGE and sagittal T2-spin echo. Fusion of FA − 3D MERGE clearly shows that f-FOV DTI and r-FOV 3N/20D are more distorted and more blurred with less anatomic precision than the other r-FOV images.

BACKGROUND AND PURPOSE

Reduced-FOV DTI is promising for exploring the cervical spinal cord, but the optimal set of parameters needs to be clarified. We hypothesized that the number of excitations should be favored over the number of diffusion gradient directions regarding the strong orientation of the cord in a single rostrocaudal axis.

MATERIALS AND METHODS

Fifteen healthy individuals underwent cervical spinal cord MR imaging at 3T, including an anatomic 3D-Multi-Echo Recombined Gradient Echo, high-resolution full-FOV DTI with a NEX of 3 and 20 diffusion gradient

Imaging Features of Malignant Lacrimal Sac and Nasolacrimal Duct Tumors

Fellows’ Journal Club

This case series presents 18 patients with primary and secondary malignant lacrimal sac and nasolacrimal duct tumors and their pattern of tumor spread. Squamous cell carcinoma was the most common histology and, in 15/18 patients tumor involved both the lacrimal sac and duct at the time of diagnosis. In 11/16 patients on CT, the nasolacrimal bony canal was smoothly expanded without erosive changes. Tumor was not observed solely within the nasolacrimal duct in any patient. Only 1 patient presented with nodal metastasis and there was no intracranial tumor extension or perineural tumor spread. The authors conclude that malignant lacrimal sac and nasolacrimal duct tumors tend to expand the nasolacrimal bony canal, rather than erode it. CT was superior to MR imaging in characterizing expansion versus erosion of the nasolacrimal bony canal.

Summary

Figure 5 from paper
A 73-year-old woman with well-differentiated SCCA of the lacrimal sac and nasolacrimal duct. A, Post-contrast-enhanced CT demonstrates an enhancing tumor within the left lacrimal sac (arrow). B, At a slightly more inferior level (bone window), note the mild expansion of the lacrimal bony canal by tumor (arrow).

The purpose of this study was to present the imaging features of primary and secondary malignant lacrimal sac and nasolacrimal duct tumors and their pattern of tumor spread in 18 patients. The most common tumor histology in our series was squamous cell carcinoma. In 15/18 patients, tumor involved both the lacrimal sac and duct at the time of diagnosis. In 11/16 patients on CT, the nasolacrimal bony canal was smoothly expanded without erosive changes. The medial canthus region (16/18) was a frequent site of direct tumor spread. Two patients had intraconal orbital spread of tumor. Tumor spread to the sinus or nasal cavity was observed in 5/13 primary tumors. Only 1 patient presented with nodal metastasis. There was

Vitamin D and Vulnerable Carotid Plaque

Fellows’ Journal Club

Angiotensin II stimulates intraplaque hemorrhage in animal models, and the angiotensin system is highly regulated by vitamin D. The authors’ purpose was to determine whether low vitamin D levels predict carotid intraplaque hemorrhage (IPH). In this cross-sectional study, 65 patients with carotid disease underwent carotid MR imaging and blood draw. Systemic clinical confounders and local lumen imaging markers were recorded. They performed multivariable Poisson regression by using generalized estimating equations to account for up to 2 carotid arteries per patient and backward elimination of confounders. The authors found that low vitamin D levels (<30 ng/mL) were a significant predictor of MRI-detected IPH, along with plaque thickness. They conclude that vitamin D insufficiency was associated with both the presence and volume of carotid IPH in patients with carotid atherosclerosis and that these results link low vitamin D levels with plaque vulnerability.

Abstract

Figure 5 from text
Vitamin D supplementation and follow-up. A, Patient 1: Baseline (upper arrow) versus 1-year follow-up (lower arrow) with vitamin D supplementation and medical therapy, including statins and antiplatelet and antihypertensive medications, demonstrates decreased IPH volume in a patient with no interval stroke (vitamin D baseline/1 year: 18.1/26.8 ng/mL; carotid IPH baseline/1 year: 0.151/0.115 cm3, or 24.1% decreased IPH volume). The patient remained asymptomatic in the year between the 2 scans. B, Patient 2: Baseline (upper arrow) versus 1-year follow-up (lower arrow) without vitamin D supplementation but with medical therapy, including statins and antiplatelet and antihypertensive medications, demonstrates minimally changed IPH volume (vitamin D baseline/1 year: 20.9/10.7 ng/mL; carotid IPH baseline/1 year: 1.041/0.996 cm3, or 4.3% decreased IPH volume). In addition, this patient had bilateral strokes in the year between the 2 scans.

BACKGROUND AND PURPOSE

MR imaging–detected carotid intraplaque hemorrhage indicates vulnerable plaque with high stroke risk. Angiotensin II stimulates intraplaque hemorrhage in animal models, and the angiotensin system is highly regulated by vitamin D. Our purpose was to determine whether low vitamin D levels predict carotid intraplaque hemorrhage in humans.

MATERIALS AND METHODS

In this cross-sectional study, 65 patients with carotid disease underwent carotid MR imaging and blood draw. Systemic clinical confounders