Yttrium-90 Radioembolization to the Prostate Gland: Proof of Concept in a Canine Model and Clinical Translation

PurposeTo investigate the feasibility, safety, and absorbed-dose distribution of prostatic artery radioembolization (RE) in a canine model.Materials and MethodsFourteen male castrated beagles received dihydroandrosterone/estradiol to induce prostatic hyperplasia for the duration of the study. Each dog underwent fluoroscopic prostatic artery catheterization. Yttrium-90 (⁹⁰Y) microspheres (TheraSphere; Boston Scientific, Marlborough, Massachusetts) were delivered to 1 prostatic hemigland (dose escalation from 60 to 200 Gy), with the contralateral side serving as a control. Assessments for adverse events were performed throughout the follow-up (Common Terminology Criteria for Adverse Events v5.0). Positron emission tomography/magnetic resonance (MR) imaging provided a confirmation after the delivery of absorbed-dose distribution. MR imaging was performed before and 3, 20, and 40 days after RE. Tissue harvest of the prostate, rectum, bladder, urethra, penis, and neurovascular bundles was performed 60 days after RE.ResultsAll the animals successfully underwent RE. Positron emission tomography/MR imaging demonstrated localization to and good coverage of only the treated hemigland. No adverse events occurred. The MR imaging showed a significant dose-dependent decrease in the treated hemigland size at 40 days (25%–60%, P < .001). No extraprostatic radiographic changes were observed. Necropsy demonstrated no gross rectal, urethral, penile, or bladder changes. Histology revealed RE-induced changes in the treated prostatic tissues of the highest dose group, with gland atrophy and focal necrosis. No extraprostatic RE-related histologic findings were observed.ConclusionsProstate ⁹⁰Y RE is safe and feasible in a canine model and leads to focal dose-dependent changes in the gland without inducing unwanted extraprostatic effects. These results suggest that an investigation of nonoperative prostate cancer is warranted.     

Vogt-Koyanagi-Harada Disease Associated with Hepatitis B Vaccination

Purpose: To report a case of Vogt–Koyanagi–Harada (VKH) disease associated with hepatitis B vaccination.

Methods: Case report.

Results: A 43-year-old Caucasian male presented with a three-week history of blurry vision, pain, photophobia, and redness in both eyes. Three days prior to the onset of symptoms, he had received the hepatitis B virus vaccine. Clinical evaluation revealed multifocal placoid lesions in the posterior pole, choroidal thickening, and serous macular detachment. Targeted laboratory investigations were negative for infectious or autoimmune markers. After treatment with oral corticosteroids, the patient had resolution of symptoms with near-total recovery of visual function. The patient later reported systemic findings of hearing loss, tinnitus, and integumentary changes. A diagnosis of VKH disease was made and inflammation was managed with oral corticosteroids followed by methotrexate for long-term disease control.

Conclusions: VKH disease is an inflammatory condition primarily affecting the choroid, retinal pigment epithelium, and outer retina. The underlying etiology is unclear, but it can be associated with a viral prodrome suggesting an infectious trigger in a genetically susceptible individual. Our case suggests that hepatitis B vaccination may trigger a similar inflammatory response.     

Región selar: evaluación mediante resonancia magnética de lesiones tumorales y pseudotumorales de baja frecuencia

ObjectiveTo show the usefulness of magnetic resonance imaging in the anatomic and pathologic characterization of the sellar region, emphasizing the differential diagnosis of uncommon non-adenomatous tumors and pseudotumors studied in our institution.ConclusionThe sellar region is a complex anatomic space with diverse types of tissues from which a wide spectrum of diseases can arise. Magnetic resonance imaging's high tissue resolution and ability to characterize the patterns of tumor growth and biological behavior make it the best imaging technique to study this region.     

Analysis of brain activity involved in chewing‐side preference during chewing: an fMRI study

The aim of this study was to investigate the activation characteristics of cerebral cortex in participants with CSP during rhythmic chewing movement. Sixteen right‐handed participants with left (two males: 29·0 ± 8·4 years old, six females: 32·3 ± 4·8 years old) or right (four males: 31·0 ± 6·1 years old, four females: 30·8 ± 4·7 years old) CSP were scanned by functional magnetic resonance imaging during rhythmic chewing. The on‐off sequence of scanning was 30 s of rhythmic chewing and 30 s of rest (off) a total of five times. The results showed that blood oxygen level‐dependent signals in the contralateral (to the CSP) primary sensorimotor cortex increased more than in the ipsilateral primary sensorimotor cortex in participants with both left and right CSP (P ≤ 0·001). Moreover, the BOLD signal within the right substantia nigra of midbrain, brainstem was more significantly (P ≤ 0·001) activated than its left counterpart in participants with left CSP, while no activation was observed in those with right CSP. The similar activation of the cerebellum was in participants with right CSP. The inferior parietal lobule, inferior frontal gyrus and left insular cortex were significantly (P ≤ 0·001) activated in participants with CSP. These findings suggest a relationship between hemispheric dominance and CSP in the primary sensorimotor cortex responsible for rhythmic chewing movement. The brainstem and the cerebellum might also play important role in the regulation of CSP. Furthermore, the IFG, IPL and insular may contribute to higher cognitive information processing for participants with CSP.     

Muscle functional MRI analysis of trunk muscle recruitment during extension exercises in asymptomatic individuals

The present study examined the activity levels of the thoracic and lumbar extensor muscles during different extension exercise modalities in healthy individuals. Therefore, 14 subjects performed four different types of extension exercises in prone position: dynamic trunk extension, dynamic–static trunk extension, dynamic leg extension, and dynamic–static leg extension. Pre‐ and post‐exercise muscle functional magnetic resonance imaging scans from the latissimus dorsi, the thoracic and lumbar parts of the longissimus, iliocostalis, and multifidus were performed. Differences in water relaxation values (T2‐relaxation) before and after exercise were calculated (T2‐shift) as a measure of muscle activity and compared between extension modalities. Linear mixed‐model analysis revealed higher lumbar extensor activity during trunk extension compared with leg extension (T2‐shift of 5.01 ms and 3.55 ms, respectively) and during the dynamic–static exercise performance compared with the dynamic exercise performance (T2‐shift of 4.77 ms and 3.55 ms, respectively). No significant differences in the thoracic extensor activity between the exercises could be demonstrated. During all extension exercises, the latissimus dorsi was the least activated compared with the paraspinal muscles. While all extension exercises are equivalent effective to train the thoracic muscles, trunk extension exercises performed in a dynamic–static way are the most appropriate to enhance lumbar muscle strength.     

Carotid Artery-Related Perioperative Stroke Following Anterior Cervical Spine Surgery: A Series of 3 Cases and Literature Review

Background

Vascular complications following anterior cervical spine surgery are rare but potentially devastating. Complications associated with the carotid artery are even more disastrous but largely anecdotal, with no more than 4 reported cases.

Is repeat head CT necessary in patients with mild traumatic intracranial hemorrhage

BackgroundPatients with traumatic intracranial hemorrhage (TIH) frequently receive repeat head CT scans (RHCT) to assess for progression of TIH. The utility of this practice has been brought into question, with some studies suggesting that in the absence of progressive neurologic symptoms, the RHCT does not lead to clinical interventions.MethodsThis was a retrospective review of consecutive patients with CT-documented TIH and GCS ≥ 13 presenting to an academic emergency department from 2009 to 2013. Demographic, historical, and physical exam variables, number of CT scans during admission were collected with primary outcomes of: neurological decline, worsening findings on repeat CT scan, and the need for neurosurgical intervention.ResultsOf these 1126 patients with mild traumatic intracranial hemorrhage, 975 had RHCT. Of these, 54 (5.5% (4.2–7.2 95 CI) had neurological decline, 73 (7.5% 5.9–9.3 95 CI) had hemorrhage progression on repeat CT scan, and 58 (5.9% 4.5–7.6 95 CI) required neurosurgical intervention. Only 3 patients (0.3% 0.1–0.9% 95 CI) underwent neurosurgical intervention due to hemorrhage progression on repeat CT scan without neurological decline. In this scenario, the number of RHCT scans needed to be performed to identify this one patient is 305.ConclusionsRHCT after initial findings of TIH and GCS ≥ 13 leading to a change to operative management in the absence of neurologic progression is a rare event. A protocol that includes selective RHCT including larger subdural hematomas or patients with coagulopathy (vitamin K inhibitors and anti-platelet agents) may be a topic for further study.