Hepatitis C virus infection in Irish drug users and prisoners - a scoping review.

BACKGROUND: Hepatitis C infection is a major public health concern globally. In Ireland, like other European countries, people who use drugs (PWUD) and prisoners carry a larger HCV disease burden than the general population. Recent advances in HCV management have made HCV elimination across Europe a realistic goal. Engaging these two marginalised and underserved populations remains a challenge. The aim of this review was to map key findings and identify gaps in the literature (published and unpublished) on HCV infection in Irish PWUD and prisoners. METHODS: A scoping review guided by the methodological framework set out by Levac and colleagues (based on previous work by Arksey & O'Malley). RESULTS: A total of 58 studies were identified and divided into the following categories; Epidemiology, Guidelines and Policy, Treatment Outcomes, HCV-related Health Issues and qualitative research reporting on Patients' and Health Providers' Experiences. This review identified significantly higher rates of HCV infection among Irish prisoners and PWUD than the general population. There are high levels of undiagnosed and untreated HCV infection in both groups. There is poor engagement by Irish PWUD with HCV services and barriers have been identified. Prison hepatology nurse services have a positive impact on treatment uptake and outcomes. Identified gaps in the literature include; lack of accurate epidemiological data on incident infection, untreated chronic HCV infection particularly in PWUD living outside Dublin and those not engaged with OST. CONCLUSION: Ireland like other European countries has high levels of undiagnosed and untreated HCV infection. Collecting, synthesising and identifying gaps in the available literature is timely and will inform national HCV screening, treatment and prevention strategies.

Ipilimumab-induced hypophysitis: MR imaging findings.

Ipilimumab is a promising new immunotherapeutic antineoplastic agent with clinical activity in the treatment of metastatic melanoma and renal cell carcinoma. With advances in immunotherapy, however, a host of new side effects related to the mechanism of action of these drugs has appeared. At our institution, 3 patients presented with hypophysitis, which was attributed to an autoimmune process based on the documented relationship of the drug to other autoimmune phenomena and significant and rapid improvement with discontinuation of the drug and addition of steroids. We present the imaging findings in 3 patients with presumed ipilimumab-induced hypophysitis.

Spinal epidural aspergillosis in a patient with HIV resulting from long-standing (3 years) lung infection.

SUMMARY: We present an unusual case of a man with human immunodeficiency virus (HIV) with pulmonary aspergillosis and spinal invasion and compression of the spinal cord occurring during a long period (3 years), as documented by MR imaging and surgical intervention. Invasive pulmonary aspergillosis with cord compression has been reported in the past, but, to the best of our knowledge, none of these have been in a patient with HIV.

Diffusion-weighted imaging and status epilepticus during vagus nerve stimulation.

PURPOSE: Transient abnormalities have been reported on diffusion-weighted imaging (DWI) during status epilepticus. Vagus nerve stimulation (VNS) is a therapy for epilepsy that has previously demonstrated alteration in regional cerebral blood flow on functional neuroimaging. We describe the peri-ictal DWI abnormalities in a patient with status epilepticus. METHODS: A 21-year-old woman with pharmacoresistant localization-related epilepsy was treated with VNS and underwent brain magnetic resonance imaging (MRI) with DWI for clinical purposes. RESULTS: Transient and reversible hyperintense signal abnormalities were noted on DWI at the site of seizure onset, in addition to the thalamus and midbrain bilaterally. A concomitant decrease in the apparent diffusion coefficient mimicked ischemia, yet complete clinical, and electrographic resolution occurred following successful termination of status. CONCLUSIONS: High-energy brain MRI sequences using DWI were safely performed in our epilepsy patient with a vagus nerve stimulator who experienced status epilepticus. This case highlights the bilateral and robust involvement of subcortical structures present immediately following status epilepticus. Additionally, bilateral abnormalities in the thalamus and midbrain in addition to the region of seizure origin, were observed in our patient implanted with a vagus nerve stimulator. Modulation of regional cerebral blood flow is one potential mechanism of action for VNS in humans; therefore, these regions of involvement could reflect the effects of status epilepticus, activation or facilitation by VNS, or both.

CT findings associated with Eagle syndrome.

Eagle syndrome is an aggregate of symptoms caused by an elongated ossified styloid process, the cause of which remains unclear. This is a rare finding that often goes undetected in the absence of radiographic studies. In this case, we present the diagnostic CT and lateral view plain film radiography findings of a 39-year-old woman with clinical evidence of Eagle syndrome. Eagle syndrome can occur unilaterally or bilaterally and most frequently results in symptoms of dysphagia, headache, pain on rotation of the neck, pain on extension of the tongue, change in voice, and a sensation of hypersalivation (1, 2). We present rare and diagnostic radiographic evidence of this on both plain film radiographs and CT scans. Although well documented in otolaryngology literature and dentistry literature, this syndrome has not been reported in the radiology literature.

Pathognomonic MR imaging findings in Balo concentric sclerosis.

Irregular, concentric zones of increased signal on T2-weighted cranial MR imaging studies may strongly suggest Balo concentric sclerosis (BCS), a rare but recognized variant of multiple sclerosis. Differentiating BCS from multiple sclerosis or neoplasm can be difficult clinically, but MR imaging findings noted in this case may be pathognomonic.

MRI measurement of brain tumor response: comparison of visual metric and automatic segmentation.

An automatic magnetic resonance imaging (MRI) multispectral segmentation method and a visual metric are compared for their effectiveness to measure tumor response to therapy. Automatic response measurements are important for multicenter clinical trials. A visual metric such as the product of the largest diameter and the largest perpendicular diameter of the tumor is a standard approach, and is currently used in the Radiation Treatment Oncology Group (RTOG) and the Eastern Cooperative Oncology Group (EGOG) clinical trials. In the standard approach, the tumor response is based on the percentage change in the visual metric and is categorized into cure, partial response, stable disease, or progression. Both visual and automatic methods are applied to six brain tumor cases (gliomas) of varying levels of segmentation difficulty. The analyzed data were serial multispectral MR images, collected using MR contrast enhancement. A fully automatic knowledge guided method (KG) was applied to the MRI multispectral data, while the visual metric was taken from the MRI films using the T1 gadolinium enhanced image, with repeat measurements done by two radiologists and two residents. Tumor measurements from both visual and automatic methods are compared to "ground truth," (GT) i.e., manually segmented tumor. The KG method was found to slightly overestimate tumor volume, but in a consistent manner, and the estimated tumor response compared very well to hand-drawn ground truth with a correlation coefficient of 0.96. In contrast, the visually estimated metric had a large variation between observers, particularly for difficult cases, where the tumor margins are not well delineated. The inter-observer variation for the measurement of the visual metric was only 16%, i.e., observers generally agreed on the lengths of the diameters. However, in 30% of the studied cases no consensus was found for the categorical tumor response measurement, indicating that the categories are very sensitive to variations in the diameter measurements. Moreover, the method failed to correctly identify the response in half of the cases. The data demonstrate that automatic 3D methods are clearly necessary for objective and clinically meaningful assessment of tumor volume in single or multicenter clinical trials.

Novel Methods of Evaluating the Growth Response Patterns of Treated Brain Tumors.

Unique methods for determining exact borders of intra-axial brain tumors using magnetic resonance imaging-based, computer-assisted, and automated systems are currently under development at the H. Lee Moffitt Cancer Center & Research Institute. Detection of tumor growth rate changes may be obtained more accurately and easily, leading to improved patient care through early institution of effective, new chemotherapy and radiotherapy regimens.

Neuroimaging of intracranial meningiomas.

MR imaging has completely revolutionized the diagnosis of intracranial processes. Topics discussed in this article include the neuroanatomic basis for imaging characteristics, angiographic findings, and the pathologic basis for the imaging appearance of meningiomas.

Midline disk herniations of the lumbar spine.

Most lumbar disk displacements occur through the lateral fibers of the posterior longitudinal ligament, whereas only a small percentage occur through the strong midline fibers. The midline disk herniation is identified as a focal midline dural sac compression and is better seen on the lateral myelogram and computed tomography scan. Of the 22 patients in this study, 14 had midline lumbar disk herniations at L4-5. Their presenting symptoms including back pain with sciatica, were similar to those of lateral disk herniations. On physical examination, however, patients commonly had only positive root tension signs with few nerve root deficits. The incidence of cauda equina syndrome was 27%. The results of treatment were much poorer in these patients than results reported with lateral herniations; 41% were good, 27% fair, and 32% poor. Surgical decompression yielded the best results. A wide exposure is usually needed to provide adequate decompression.

Medial temporal atrophy as a magnetic resonance imaging marker for Alzheimer's disease.

Medial temporal lobe atrophy (MTLA) on brain magnetic resonance imaging (MRI) may help differentiate Alzheimer's disease (AD) from multiinfarct dementia (MID) and other dementias. MTLA was seen in 6 of 11 patients with clinically diagnosed AD, 16 of 20 with mixed dementia (with both AD and MID), 1 of 5 with psychiatric disease, and in none of 32 with MID or 8 with other dementias (p less than 0.0001). Increased patchy periventricular signal, or "unidentified bright objects" were seen in 2 of 11 patients with AD, 10 of 20 patients with AD and MID, and 26 of 32 patients with MID. A larger series with autopsy correlation may verify that MTLA is a reasonably specific marker for AD, and unidentified bright objects are a sensitive, but not specific, marker for vascular dementias.

Magnetic resonance imaging evaluation of congenital dislocation of the hips.

Magnetic resonance (MR) images were obtained preoperatively and postoperatively for 12 pediatric patients with congenital dislocation of the hip (CDH). The images were compared with arthrograms and computed tomography scans. The MR images were more accurate in defining soft-tissue anatomy, hip position, and obstructive factors to relocation. MR imaging is an efficient diagnostic tool in CDH.

Progressive necrotizing myelopathy associated with leukemia: clinical, pathologic, and MRI correlation.

We describe a patient with progressive, irreversible, necrotizing myelopathy associated with myelomonocytic leukemia. The neuropathologic lesions consisted of diffuse necrosis, most pronounced in the cervical cord and affecting both the gray and white matter. These areas corresponded to areas of increased T2 on magnetic resonance imaging scans of the patient. We felt that there was no causal relationship of these lesions to any single antileukemic agent the patient received, and no other local or systemic causes were found to explain the lesions at necropsy. It is suggested that our case is an example of paraneoplastic necrotizing myelopathy. To our knowledge, this is the third case of necrotizing myelopathy associated with leukemia reported in the English medical literature, and the first one demonstrating usefulness of magnetic resonance imaging in diagnosis of necrotizing myelopathy.