Signal-to-noise per unit time optimization for in vivo single-voxel proton magnetic resonance spectroscopy of the brain: Theoretical formulation and experimental verification at two field strengths

Signal-to-noise ratio optimization, regarding repetition time selection, was explored mathematically and experimentally for single-voxel proton magnetic resonance spectroscopy. Theoretical findings were benchmarked against phantom measurements at 1.5 Tesla and localized in vivo proton brain spectra acquired at both 1.5 Tesla/3.0 Tesla. A detailed mathematical description of signal-to-noise ratio per unit time was derived, yielding an optimal repetition time of 1.256 times the metabolite longitudinal relaxation time. While long-repetition-time acquisitions minimize longitudinal relaxation time contributions, a repetition time of ~1.5s results in maximum signal-to-noise ratio per unit time, which can in turn be invested into smaller voxel sizes. The latter is of utmost importance in brain oncology, allowing accurate spectroscopic characterization of small lesions.Comment: 26 pages, 4 figures, submitted to Spectroscopy Letter

Case Report Adventitious Bursitis Overlying an Osteochondroma of the Humerus Facing the Thoracic Wall

One of the complications of osteochondromas is the development of a bursa over the cartilaginous cap. We report a 15-year-old boy with a rapidly expanded adventitious bursitis overlying an osteochondroma of the humerus facing the thoracic wall, a location not previously reported for such bursa formation. Magnetic resonance imaging readily showed adventitious bursitis overlying the osteochondroma, thereby dispelling concerns for malignant transformation

A rare case of complete C2–C3 dislocation with mild neurological symptoms

The authors report a rare case of complete C2–C3 dislocation with unexpectedly mild neurological symptoms in a 57 year old man involved in a motor vehicle accident, who had previously undergone posterior laminectomy from C3 through C7. A retrospective chart analysis and a thorough radiographic review were performed. X-rays and CT of the cervical spine demonstrated a complete dislocation at the C2–C3 level. Computed tomographic angiography revealed disruption of both vertebral arteries; however, blood flow was evident in the basilar artery. After radiologically guided placement in cervical traction with tongs that reduced the subluxation by approximately 50% the patient had spontaneous eye opening and was able to follow commands. A two-stage 360(o) stabilization and fusion was performed and the patient was finally discharged 24 days after admission with his neurological status essentially unchanged. In conclusion, our patient presented with surprisingly mild neurological symptoms. The previously performed laminectomy could have both predisposed to injury as well as protected his spinal cord from potentially fatal trauma

Historic Evolution of Open Cingulectomy and Stereotactic Cingulotomy in the Management of Medically Intractable Psychiatric Disorders, Pain and Drug Addiction

Stereotactic cingulotomy constitutes a psychosurgical procedure nowadays advocated in the treatment of medically intractable obsessive-compulsive disorder, chronic pain and drug addiction. From its theoretical conception to the first cingulectomies performed and modern stereotactic-guided cingulotomies, various target localization methods, different surgical techniques, and numerous lesioning devices have been utilized. In the current article, the authors performed a literature review related to cingular lesion placement in an effort to identify misconceptions of the past, recapitulate existing knowledge and recognize targets for further research. The initial animal and human electrophysiologic experimental data regarding the role of the cingulate cortex in various behavioral and cognitive functions were meticulously reviewed. The clinical indications, surgical technique and the clinical results and complications of open cingulectomies were examined. The anatomic target localization methodologies, surgical technique, and the outcome of the initial stereotactic cingulotomy procedures were reviewed, and the evolution of the imaging techniques, stereotactic devices, and lesioning strategies were followed. The modern advanced surgical techniques, clinical outcome and the procedure-associated complications were analyzed with particular emphasis on the emotional, behavioral, and cognitive procedure-induced changes. Large-scale prospective studies with strict inclusion and well-defined, objective outcome criteria are necessary for defining the role of stereotactic cingulotomy in the current psychosurgical armamentarium. Copyright (C) 2009 S. Karger AG, Base

Role of endoscopic third ventriculostomy in treatment of selected patients with normal pressure hydrocephalus

Objective: The purpose of our study was to evaluate the results of endoscopic third ventriculostomy (ETV) in the management of patients with idiopathic normal pressure hydrocephalus (INPH). Methods: Our prospective study included seven patients (five men and two women; ages ranging between 68 and 78 years) with two or more typical NPH symptoms of short duration (<6 months), with no other morbidity factors, with a Mini-Mental State Examination (MMSE) score ≥18, aqueductal cerebrospinal fluid (CSF) stroke volume ≥42 μL, and positive lumbar drain test. The etiology of NPH was idiopathic in all of these cases. Their preoperative work-up included brain magnetic resonance imaging (MRI) and cine-MR, MMSE test, and CSF lumbar drain test, in all cases. The clinical status of all participants was graded using the Japanese intractable hydrocephalus system. An ETV was performed in all participants. Follow-up included periodic clinical evaluations, MMSE, and MRI with cine-MR studies. The follow-up time range was 12-72 months. Results: The mean postoperative clinical grade was 3.1, while the preoperative was 6.1. Gait disturbance and urinary incontinence were the most responsive symptoms. The mean postoperative MMSE score was 23.6, while the preoperative score was 20.3. The mean postoperative aqueductal CSF stroke volume, 6 months after the procedure, was 31.6 μL, while the preoperative volume was 48.8 μL. Conclusions: ETV may be a safe alternative surgical option for a limited number of carefully selected INPH patients

Clinical and imaging evaluation of the response to intravenous steroids in patients with Graves&rsquo; orbitopathy and analysis on who requires additional therapy

Theodora Tsirouki,1 Alexandra Bargiota,2 Stelios Tigas,3 Agathi Vasileiou,2 Eftichia Kapsalaki,4 Zoe Giotaki,3 Ioannis Asproudis,5 Agathokles Tsatsoulis,3 Georgios Koukoulis,2 Evangelia E Tsironi1 1Department of Ophthalmology, University Hospital of Larissa, Larissa, 2Department of Endocrinology, University Hospital of Larissa, Larissa,&nbsp;3Department of Endocrinology, University Hospital of Ioannina, Ioannina, 4Department of Diagnostic Radiology, University Hospital of Larissa, Larissa, 5Department of Ophthalmology, University Hospital of Ioannina, Ioannina, Greece Objective: The aim of this study was to evaluate the safety and efficacy of an individualized steroid regimen in patients with moderate-to-severe Graves&rsquo; orbitopathy (GO) by monitoring clinical and imaging parameters. Methods: In total, 47 patients with active, moderate-to-severe GO were enrolled in this study. All the patients received the proposed treatment regimen by European Group on GO of 4.5 g of intravenous (IV) methylprednisolone for 12 weeks. At the end of the IV treatment, patients with persistent active GO (Group 1) who were assessed by clinical examination and orbital imaging with short tau inversion recovery-sequence magnetic resonance imaging (STIR MRI) received additional treatment with oral prednisolone, and those with inactive GO (Group 2) received no further treatment. Results: Of the 42 patients who completed the study, 22 (52.4%) patients formed Group 1 and 20 (47.6%) patients Group 2. At the 12th week, the overall response to IV treatment was 76.2%, and clinical activity score (CAS) improvement was 69%. At the 24th week, the overall response was 92.8%, and CAS improvement was 97.6%, without statistically significant difference in CAS and total eye score between these two groups (P=0.157 and P=0.856, respectively). Ophthalmic manifestations were improved, being absent or minimal in 78.6% of patients at the 24th week follow-up. Recurrence of disease activity occurred in 9.5% of patients up to 24 weeks after the completion of treatment, and major adverse events occurred in 6.4% of patients. Conclusion: In patients with moderate-to-severe GO, IV steroid treatment, followed by oral treatment, when needed, is an effective regimen with low rates of adverse events and recurrences. STIR MRI is a significant tool for recognizing patients who need additional steroid treatment. Keywords: Graves&rsquo; orbitopathy, magnetic resonance imaging, MRI, glucocorticoids&nbsp