Early outcomes and periprocedural complications of transarterial embolization of brain arteriovenous malformations with Onyx®.

BACKGROUND: Brain arteriovenous malformation (BAVM) is a rare pathology diagnosed mostly in young adults. However, due to its hemorrhagic complications, it constitutes an important clinical problem. Treatment modalities available include endovascular, surgery and radiosurgery. The aim of the study was to assess the efficacy and safety of endovascular treatment of BAVM with Onyx® by reporting one-center experience. MATERIAL AND METHODS: Between 2006 and 2013, 54 patients with BAVM were embolized with Onyx. The group consisted of 24 males and 30 females, aged 10 to 65 years (mean 42.6±15.4). Clinical manifestations of BAVMs were: hemorrhage in 27 (50.0%), headaches in 12 (22.2%), seizures in 7 (13.0%) and focal neurologic deficits in 2 (3.7%) patients. Six (11.1%) patients were asymptomatic. A majority of BAVMs were of II and III grade in Spetzler-Martin scale (19 and 22 cases respectively). RESULTS: A total number of 108 endovascular procedures were performed (mean 2.00±0.98 sessions/patient). Complete obliteration of malformation was achieved in 25 (46.3%) patients, mostly with grade II and III BAVMs. In 29 (53.7%) patients, embolization led to a decrease in size of BAVM that made it feasible for other treatment modality. Morbidity and mortality rates were 5.6% and 1.8% respectively. The rate of hemorrhagic complications was 9.3%. CONCLUSION: Embolization of BAVM with Onyx® is an effective and safe method of treatment. However, regarding type and consequences of complications, the technique needs further improvement.

Are T2-weighted images more useful than T1-weighted contrast-enhanced images in assessment of postoperative sella and parasellar region?

BACKGROUND: The proper diagnosis and management of patients after surgery for pituitary tumors are of great importance in clinical practice. The purpose of this study was to investigate the magnetic resonance features of the postoperative sella with fast spin echo T2-weighted imaging and to evaluate the benefits of this sequence compared to the classically performed contrast-enhanced T1-weighted imaging at 1.5T unit. MATERIAL/METHODS: The study group consisted of 101 patients who underwent resection of pituitary tumors. There were 58 women (57.4%), aged 22 to 75 (mean age, 52.67 years) and 43 men (42.6%), aged 21 to 79 (mean age, 49 years). In all patients preoperative and multiple postoperative MR studies were performed. Post-contrast T1 and pre-contrast T2 images were interpreted by 2 independent readers (neuroradiologists). RESULTS: Contrast-enhanced T1-weighted imaging was significantly superior to T2-weighted imaging in assessment of infundibulum (p<0.05). There was no statistically significant difference for each of readers between T1- and T2-weighted images regarding to the following features: visualization of residual pituitary gland (p = 0.062 and p = 0.368), contours of pituitary (p = 0.959 and p = 0.265), optic chiasm (p = 0.294 and p = 0.843), and visualization of presence of residual tumor (p = 0.204 and p = 0.169). T2-weighted images were significantly superior to contrast-enhanced T1-weighted imaging with regard to visualization of contours of residual tumors (p<0.05). CONCLUSIONS: T2-weighted images may help to discriminate tumorous from non-tumorous involvement of the postoperative sella and the sphenoid sinus. T2-weighted images are also very useful for a long time after the resection in the postoperative evaluation of the implanted muscle with fascia.

Analysis of metabolic changes of brain in HIV-1 seropositive patients with proton magnetic resonance spectroscopy.

BACKGROUND: Asymptomatic central nervous system involvement may occur in the early stages of the HIV infection. The aim of the study was to evaluate early brain metabolic changes by means of proton MR spectroscopy (H1MRS) in the HIV-1 seropositive patients without neurological deficits or significant abnormalities in the plain MR study. MATERIAL/METHODS: The H1MRS examinations were performed with the use of a MR GE Signa 1,5T system. There were 39 subjects examined, aged 21 to 57 years (mean age 35 years) were examined, including 25 patients infected with HIV-1 and 14 healthy volunteers who constituted a control group. The examinations were performed using the Single Voxel Spectroscopy technique with the PRESS sequence, with following parameters: TR=1500 ms, TE=35 ms, number of acquisitions =128, time of acquisition =3 min. 43 sec. Voxels of 8 cm(3) (20×20×20 mm) in size were located in the following 5 regions: posterior cingulate gyrus, grey matter of the frontal area, left basal ganglia, white matter of the left parietal area and white matter of the frontal area. The NAA/Cr, Cho/Cr, mI/Cr ratios in the defined regions of interest were statistically analyzed. RESULTS: There was a statistically significant decrease (p<0.05) in the NAA/Cr ratios in the posterior cingulate area and white matter of the left parietal area in HIV-1 seropositive patients, as compared to the control group. Other metabolite ratios in all the above mentioned locations showed no statistically significant differences, as was also the case for NAA/Cr ratios in grey matter of the frontal area, left basal ganglia and white matter of the frontal area. CONCLUSIONS: The reduction of NAA/Cr values revealed in H1MRS studies suggests loss of neurons/neuronal activity in the posterior cingulate area and white matter of the left parietal area, in patients with HIV-1 at the stage before clinical manifestations of retroviral infection and structural changes in the plain MR study. This may reflect a direct neurotropic activity of HIV.

Diagnostic value of gadolinium-enhanced MR imaging of active sacroiliitis in seronegative spondyloarthropathy.

BACKGROUND: SERONEGATIVE SPONDYLOARTHROPATHY (SPA) IS A GROUP OF DISEASES INCLUDING: ankylosing spondylitis, psoriatic spondyloarthrithis, reactive arthritis, spondyloarthrithis associated with inflammatory bowel disease, and undifferentiated spondyloarthritis. One of the diagnostic criteria of SpA is the presence of sacroiliitis. Periarticular bone marrow oedema (histologically corresponding to osteitis) is a primary symptom of the active stage of inflammation, which can be identified by MR using T2-weighted images. Its presence is essential for the therapeutic decision. The aims of this study were: 1. to compare the diagnostic value of T2-weighted images with T1 gadolinium-enhanced fat saturation (FS) images. 2. to establish if T1 gadolinium-enhanced images increase the diagnostic value of the MRI examination. MATERIAL/METHODS: With the use of a 1.5T MRI scanner, 35 patients aged 19-67 years were examined. They were classified as having SpA or suspicious of SpA. The following findings were assessed: bone marrow oedema, synovitis, capsulitis/enthesistis. They were evaluated and compared on T2 and T1 gadolinium-enhanced FS images. RESULTS: Active sacroiliitis was identified in 21 patients, chronic in 1 patient. Two patients had signs of synovitis without any features of bone marrow oedema. One patient had fracture of the sacral bone. Ten patients had no signs of sacroiliitis. There was no significant difference in the diagnostic value between FSE T2 images and T1 gadolinium-enhanced images with FS in the evaluation of bone marrow oedema and capsulitis/enthesitis. However, T1 gadolinium-enhanced images were more sensitive than FSE T2 images in visualising synovitis. CONCLUSIONS: MRI is a very sensitive method to identify active sacroiliitis in SpA. MRI without contrast administration is sufficient to identify bone marrow oedema as a crucial finding in active sacroiliitis. The gadolinium-enhanced images make the diagnosis easier, especially in patients with minimal bone marrow oedema because they reveal or better depict synovitis, while they do not improve visualisation of capsulitis/enthesitis.