Facet arthropathy evaluation: CT or MRI?

OBJECTIVE: To assess the reliability of lumbar facet arthropathy evaluation with computed tomography (CT) or magnetic resonance imaging (MRI) in patients with and without lumbar disc prosthesis and to estimate the reliability for individual CT and MRI findings indicating facet arthropathy. METHODS: Metal-artifact reducing CT and MRI protocols were performed at follow-up of 114 chronic back pain patients treated with (n = 66) or without (n = 48) lumbar disc prosthesis. Three experienced radiologists independently rated facet joint space narrowing, osteophyte/hypertrophy, erosions, subchondral cysts, and total grade facet arthropathy at each of the three lower lumbar levels on both CT and MRI, using Weishaupt et al's rating system. CT and MRI examinations were randomly mixed and rated independently. Findings were dichotomized before analysis. Overall kappa and (due to low prevalence) prevalence- and bias-adjusted kappa were calculated to assess interobserver agreement. RESULTS: Interobserver agreement on total grade facet arthropathy was moderate at all levels with CT (kappa 0.47-0.48) and poor to fair with MRI (kappa 0.20-0.32). Mean prevalence- and bias-adjusted kappa was lower for osteophyte/hypertrophy versus other individual findings (CT 0.58 versus 0.79-0.86, MRI 0.35 versus 0.81-0.90), higher with CT versus MRI when rating osteophyte/hypertrophy (0.58 versus 0.35) and total grade facet arthropathy (0.54 versus 0.31), and generally similar at levels with versus levels without disc prosthesis. CONCLUSION: Interobserver agreement on facet arthropathy was moderate with CT and better with CT than with MRI. Disc prosthesis did not influence agreement. A more reliable grading of facet arthropathy requires a more consistent evaluation of osteophytes/hypertrophy. KEY POINTS: • In this study, interobserver agreement on facet arthropathy (FA) severity-based on facet joint space narrowing, osteophyte/hypertrophy, erosions, and subchondral cysts-was better with CT versus MRI. • Metal-artifact reducing CT and MRI protocols helped to improve visibility and maintain agreement when evaluating severity of FA at levels with metallic disc prosthesis. • Agreement was poorer for severity of osteophytes/hypertrophy than for the other evaluated FA findings; improved agreement on total grade FA evaluated with CT or MRI thus requires more consistent grading of osteophytes/hypertrophy between different radiologists.

NOR-SASS (Norwegian Sonothrombolysis in Acute Stroke Study): Randomized Controlled Contrast-Enhanced Sonothrombolysis in an Unselected Acute Ischemic Stroke Population.

BACKGROUND AND PURPOSE: The NOR-SASS (Norwegian Sonothrombolysis in Acute Stroke Study) aimed to assess effect and safety of contrast-enhanced ultrasound treatment in an unselected acute ischemic stroke population. METHODS: Patients treated with intravenous thrombolysis within 4.5 hours after symptom onset were randomized 1:1 to either contrast-enhanced sonothrombolysis (CEST) or sham CEST. A visible arterial occlusion on baseline computed tomography angiography was not a prerequisite for inclusion. Pulse-wave 2 MHz ultrasound was given for 1 hour and contrast (SonoVue) as an infusion for ≈30 minutes. Magnetic resonance imaging and angiography were performed after 24 to 36 hours. Primary study end points were neurological improvement at 24 hours defined as National Institutes of Health Stroke Scale score 0 or reduction of ≥4 National Institutes of Health Stroke Scale points compared with baseline National Institutes of Health Stroke Scale and favorable functional outcome at 90 days defined as modified Rankin scale score 0 to 1. RESULTS: A total of 183 patients were randomly assigned to either CEST (93 patient) or sham CEST (90 patients). The rates of symptomatic intracerebral hemorrhage, asymptomatic intracerebral hemorrhage, or mortality were not increased in the CEST group. Neurological improvement at 24 hours and functional outcome at 90 days was similar in the 2 groups both in the intention-to-treat analysis and in the per-protocol analysis. CONCLUSIONS: CEST is safe among unselected ischemic stroke patients with or without a visible occlusion on computed tomography angiography and with varying grades of clinical severity. There was, however, statistically no significant clinical effect of sonothrombolysis in this prematurely stopped trial. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01949961.

Fat in the lumbar multifidus muscles - predictive value and change following disc prosthesis surgery and multidisciplinary rehabilitation in patients with chronic low back pain and degenerative disc: 2-year follow-up of a randomized trial.

BACKGROUND: Evidence is lacking on whether fat infiltration in the multifidus muscles affects outcomes after total disc replacement (TDR) surgery and if it develops after surgery. The aims of this study were 1) to investigate whether pre-treatment multifidus muscle fat infiltration predicts outcome 2 years after treatment with TDR surgery or multidisciplinary rehabilitation, and 2) to compare changes in multifidus muscle fat infiltration from pre-treatment to 2-year follow-up between the two treatment groups. METHODS: The study is secondary analysis of data from a trial with 2-year follow-up of patients with chronic low back pain (LBP) and degenerative disc randomized to TDR surgery or multidisciplinary rehabilitation. We analyzed (aim 1) patients with both magnetic resonance imaging (MRI) at pre-treatment and valid data on outcome measures at 2-year follow-up (predictor analysis), and (aim 2) patients with MRI at both pre-treatment and 2-year follow-up. Outcome measures were visual analogue scale (VAS) for LBP, Oswestry Disability Index (ODI), work status and muscle fat infiltration on MRI. Patients with pre-treatment MRI and 2-year outcome data on VAS for LBP (n = 144), ODI (n = 147), and work status (n = 137) were analyzed for prediction purposes. At 2-year follow-up, 126 patients had another MRI scan, and change in muscle fat infiltration was compared between the two treatment groups. Three radiologists visually quantified multifidus muscle fat in the three lower lumbar levels on MRI as <20% (grade 0), 20-50% (grade 1), or >50% (grade 2) of the muscle cross-section containing fat. Regression analysis and a mid-P exact test were carried out. RESULTS: Grade 0 pre-treatment multifidus muscle fat predicted better clinical results at 2-year follow-up after TDR surgery (all outcomes) but not after rehabilitation. At 2-year follow-up, increased fat infiltration was more common in the surgery group (intention-to-treat p = 0.03, per protocol p = 0.08) where it was related to worse pain and ODI. CONCLUSIONS: Patients with less fat infiltration of multifidus muscles before TDR surgery had better outcomes at 2-year follow-up, but findings also indicated a negative influence of TDR surgery on back muscle morphology in some patients. The rehabilitation group maintained their muscular morphology and were unaffected by pre-treatment multifidus muscle fat. TRIAL REGISTRATION: NCT 00394732 (retrospectively registered October 31, 2006).

Do more MRI findings imply worse disability or more intense low back pain? A cross-sectional study of candidates for lumbar disc prosthesis.

OBJECTIVE: To examine whether combined magnetic resonance imaging (MRI) findings are related to the degree of disability and low back pain (LBP) in candidates for lumbar disc prosthesis surgery. MATERIALS AND METHODS: This cross-sectional study included 170 disc prosthesis candidates (mean age 41 years; 88 women) with chronic non-radicular LBP and localized disc degeneration. Experienced radiologists rated Modic changes and disc findings at L4-S1 on pre-treatment MRIs. An MRI total score (0-10) for findings at L4/L5 plus L5/S1 was calculated for Modic type I and/or II changes, a posterior high intensity zone (HIZ) in the disc, dark/black nucleus pulposus signal, and ≥40 % disc height decrease. We analyzed the relationship of the MRI total score to the Oswestry Disability Index (ODI) (n = 170) and LBP intensity scores (0-100 visual analogue scale, n = 165) using multiple linear regression and adjusting for age, gender, body mass index, smoking, and anxiety/depression. RESULTS: The MRI total score was not related to ODI (regression coefficient 0.12, p = 0.79) or LBP intensity (regression coefficient 0.64, p = 0.37). When individual MRI findings were analyzed, patients with HIZ at L5/S1 had slightly lower ODI scores (4.7 points, p = 0.02). In post hoc analyses, results remained unchanged after adding facet arthropathy to the MRI total score and adjusting also for physical workload and physical leisure-time activity. CONCLUSIONS: The combined MRI findings were not related to the degree of disability or the intensity of LBP. These degenerative MRI findings cannot explain variation in pre-treatment disability and pain in patients with chronic LBP accepted for disc prosthesis surgery.

Reliability of MRI findings in candidates for lumbar disc prosthesis.

INTRODUCTION: Limited reliability data exist for localised magnetic resonance imaging (MRI) findings relevant to planning of treatment with lumbar disc prosthesis and later outcomes. We assessed the reliability of such findings in chronic low back pain patients who were accepted candidates for disc prosthesis. METHODS: On pretreatment MRI of 170 patients (mean age 41 years; 88 women), three experienced radiologists independently rated Modic changes, disc findings and facet arthropathy at L3/L4, L4/L5 and L5/S1. Two radiologists rerated 126 examinations. For each MRI finding at each disc level, agreement was analysed using the kappa statistic and differences in prevalence across observers using a fixed effects model. RESULTS: All findings at L3/L4 and facet arthropathy at L5/S1 had a mean prevalence <10% across observers and were not further analysed, ensuring interpretable kappa values. Overall interobserver agreement was generally moderate or good (kappa 0.40-0.77) at L4-S1 for Modic changes, nucleus pulposus signal, disc height (subjective and measured), posterior high-intensity zone (HIZ) and disc contour, and fair (kappa 0.24) at L4/L5 for facet arthropathy. Posterior HIZ at L5/S1 and severely reduced subjective disc height at L4/L5 differed up to threefold in prevalence between observers (p < 0.0001). Intraobserver agreement was mostly good or very good (kappa 0.60-1.00). CONCLUSION: In candidates for disc prosthesis, mostly moderate interobserver agreement is expected for localised MRI findings.

Predictors of outcome after surgery with disc prosthesis and rehabilitation in patients with chronic low back pain and degenerative disc: 2-year follow-up.

PURPOSE: A prospective study to evaluate whether certain baseline characteristics can predict outcome in patients treated with disc prosthesis or multidisciplinary rehabilitation. METHODS: Secondary analysis of 154 patients with chronic low back pain (LBP) for at least 1 year and degenerative discs originally recruited for a randomized trial. Outcome measures were Oswestry Disability Index (ODI) dichotomized to < or ≥15 points improvement and whether subjects were working at 2-year follow-up. A multiple logistic regression analysis was used. RESULTS: In patients treated with disc prosthesis, long duration of LBP and high Fear-Avoidance Beliefs for work (FABQ-W) predicted worse ODI outcome [odds ratio (OR) = 1.9, 95% confidence interval (CI) 1.2-3.2 and OR = 1.7, CI 1.2-2.4 for every 5 years or 5 points]. Modic type I or II predicted better ODI outcome (OR = 5.3, CI 1.1-25.3). In patients treated with rehabilitation, a high ODI, low emotional distress (HSCL-25), and no daily narcotics predicted better outcome for ODI (OR = 2.5, CI 1.4-4.5 for every 5 ODI points, OR = 2.1, CI 1.1-5.1 for every 0.5 HSCL points and OR = 23.6, CI 2.1-266.8 for no daily narcotics). Low FABQ-W and working at baseline predicted working at 2-year follow-up after both treatments (OR = 1.3, CI 1.0-1.5 for every 5 points and OR = 4.1, CI 1.2-13.2, respectively). CONCLUSIONS: Shorter duration of LBP, Modic type I or II changes and low FABQ-W were the best predictors of success after treatment with disc prosthesis, while high ODI, low distress and not using narcotics daily predicted better outcome of rehabilitation. Low FABQ-W and working predicted working at follow-up.

Reliability of change in lumbar MRI findings over time in patients with and without disc prosthesis--comparing two different image evaluation methods.

OBJECTIVES: To assess the reliability of change in lumbar magnetic resonance imaging (MRI) findings evaluated retrospectively by direct comparison of images and by non-comparison. MATERIALS AND METHODS: Pre-treatment and 2-year follow-up MRI was performed in 126 patients randomized to disc prosthesis surgery or non-surgical treatment. Two experienced radiologists independently evaluated progress and regress for Modic changes, disc findings, and facet arthropathy (FA) at L3/L4, L4/L5, and L5/S1, both by non-comparison and by comparison of initial and follow-up images. FA was evaluated at all levels, and other findings at non-operated levels. We calculated prevalence- and bias-adjusted kappa (PABAK) values for interobserver agreement. The impact of an adjacent prosthesis (which causes artefacts) and image evaluation method on PABAK was assessed using generalized estimating equations. RESULTS: Image comparison indicated good interobserver agreement on progress and regress (PABAK 0.63-1.00) for Modic changes, posterior high-intensity zone, disc height, and disc contour at L3-S1 and for nucleus pulposus signal and FA at L3/L4; and moderate interobserver agreement (PABAK 0.46-0.59) on decreasing nucleus signal and increasing FA at L4-S1. Image comparison indicated lower (but fair) interobserver agreement (PABAK 0.29) only for increasing FA at L5/S1 in patients with prosthesis in L4/L5 and/or L5/S1. An adjacent prosthesis had no overall impact on PABAK values (p ≥ 0.22). Comparison yielded higher PABAK values than non-comparison (p < 0.001). CONCLUSIONS: Regarding changes in lumbar MRI findings over time, comparison of images can provide moderate or good interobserver agreement, and better agreement than non-comparison. An adjacent prosthesis may not reduce agreement on change for most findings.

Localized cerebral energy failure in DNA polymerase gamma-associated encephalopathy syndromes.

Mutations in the catalytic subunit of the mitochondrial DNA-polymerase gamma cause a wide spectrum of clinical disease ranging from infantile hepato-encephalopathy to juvenile/adult-onset spinocerebellar ataxia and late onset progressive external ophthalmoplegia. Several of these syndromes are associated with an encephalopathy that characteristically shows episodes of rapid neurological deterioration and the development of acute cerebral lesions. The purpose of this study was to investigate the nature, distribution and natural evolution of central nervous system lesions in polymerase gamma associated encephalopathy focusing particularly on lesions identified by magnetic resonance imaging. We compared radiological, electrophysiological and pathological findings where available to study potential mechanisms underlying the episodes of exacerbation and acute cerebral lesions. We studied a total of 112 magnetic resonance tomographies and 11 computed tomographies in 32 patients with polymerase gamma-encephalopathy, including multiple serial examinations performed during both the chronic and acute phases of the disease and, in several cases, magnetic resonance spectroscopy and serial diffusion weighted studies. Data from imaging, electroencephalography and post-mortem examination were compared in order to study the underlying disease process. Our findings show that magnetic resonance imaging in polymerase gamma-related encephalopathies has high sensitivity and can identify patterns that are specific for individual syndromes. One form of chronic polymerase gamma-encephalopathy, that is associated with the c.1399G > A and c.2243G > C mutations, is characterized by progressive cerebral and cerebellar atrophy and focal lesions of the thalamus, deep cerebellar structures and medulla oblongata. Acute encephalopathies, both infantile and later onset, show similar pictures with cortical stroke-like lesions occurring during episodes of exacerbation. These lesions can occur both with and without electroencephalographic evidence of concurrent epileptic activity, and have diffusion, spectroscopic and histological profiles strongly suggestive of neuronal energy failure. We suggest therefore that both infantile and later onset polymerase gamma related encephalopathies are part of a continuum.

Facet Arthropathy Following Disc Replacement Versus Rehabilitation: A Prospective Study With 8-Year Follow-Up.

STUDY DESIGN: A prospective study of patients originally randomized to total disc replacement (TDR) or multidisciplinary rehabilitation. OBJECTIVE: To assess the long-term development of facet arthropathy (FA) after TDR versus nonoperative treatment, and to analyze the association between FA and clinical outcome. SUMMARY OF BACKGROUND DATA: FA may appear or increase following TDR, but the natural course of FA is unclear, and no previous study has evaluated the long-term development of FA following TDR compared with nonoperative treatment. METHODS: The study included 126 patients with chronic low back pain and degenerative changes in the lumbar intervertebral discs. The patients underwent pretreatment and 8-year follow-up magnetic resonance imaging (MRI) and 8-year follow-up computed tomography (CT) of the lumbar spine. The primary outcome measure was FA development (yes/no) on MRI at index level L4/L5 or L5/S1, defined as increased FA grade value from pretreatment to follow-up according to Weishaupt grading system. Secondary outcomes included the association between FA (on MRI and CT) and Oswestry Disability Index (ODI) or back pain as well as reoperations. RESULTS: Increased index level FA grade was more frequent after TDR versus nonoperative treatment (36%, 25/69 vs. 2%, 1/57 of patients, P < 0.001), but was not related to change in ODI or back pain. At follow-up, index level FA grades were higher after TDR versus nonoperative treatment (odds ratio 4.0 MRI and 5.9 CT), but were not related to ODI less than or equal to 22. Four patients (6%) treated with TDR and no patients treated nonoperatively were operated for lateral recess stenosis with posterior decompression at the index level during follow-up. CONCLUSION: Index level FA development was more likely after TDR compared with nonoperative treatment but was not associated with the 8-year clinical outcome. Index level FA may have contributed to reoperations in the TDR group. LEVEL OF EVIDENCE: 2.

Fractal dimension analysis of MR images reveals grey matter structure irregularities in schizophrenia.

The fractal dimension (FD) was used to reveal brain structure irregularities in patients with schizophrenia. FD provides a unique way of quantifying the shape complexity of cortical folding of the human brain. MR images were obtained from seven patients with schizophrenia that were compared with six healthy control subjects. The MR images were first segmented, and the FD was calculated for the grey/white matter boundary for the whole brain and the hemispheres separately, using the box-counting and Minkowski-Bouligand methods. The results showed that the patients had larger FD values than the controls, for the whole brain volume and right hemisphere.

Clinical Importance of Temporal Bone Features for the Efficacy of Contrast-Enhanced Sonothrombolysis: a Retrospective Analysis of the NOR-SASS Trial.

Contrast-enhanced sonothrombolysis (CEST) seems to be a safe and promising treatment in acute ischemic stroke. It remains unknown if temporal bone features may influence the efficacy of CEST. We investigated the association between different temporal bone features on admission computed tomography (CT) scan and the outcome in acute ischemic stroke patients included in the randomized Norwegian Sonothrombolysis in Acute Stroke Study (NOR-SASS). Patients diagnosed as stroke mimics and those with infratentorial stroke or with incorrect insonation were excluded. We retrospectively assessed temporal bone heterogeneity (presence of diploë), diploë ratio, thickness, and density on admission CT scans. National institute of Health Stroke Scale (NIHSS) at 24 h and modified Rankin Scale (mRS) at 3 months were correlated with CT findings both in CEST and sham CEST patients. A total of 99 patients were included of which 52 were assigned to CEST and 47 to sham CEST. Approximately 20% patients had a heterogeneous temporal bone in both the CEST and sham CEST group. All temporal bone CT features studied were associated with female sex. In the CEST group, temporal bone heterogeneity (p = 0.006) and higher temporal bone diploë ratio (p = 0.002) were associated with higher NIHSS at 24 h. There was no association between temporal bone features and mRS at 3 months. Approximately 20% of acute ischemic stroke patients have heterogeneous temporal bone and may be resistant to standard 2-MHz transcranial Doppler ultrasound treatment. Sonothrombolysis resistance may easily be predicted by admission CT for better selection.

Excellent response of intramedullary Erdheim-Chester disease to vemurafenib: a case report.

BACKGROUND: Erdheim-Chester disease is a rare histiocytosis characterized by multi-systemic organ involvement. Immune-modulating agents such as interferon-alpha have limited success and the disorder is progressive and causes high morbidity and mortality. Treatment with the BRAF-inhibitor vemurafenib has recently produced substantial improvement in three patients with Erdheim-Chester disease expressing the p. V600E BRAF mutation. The disorder commonly affects the central nervous system and it is not yet known whether vemurafenib can reverse intra-axial infiltration and the resulting neurological impairment. CASE PRESENTATION: In this work, we report for the first time an excellent clinical response to vemurafenib in a Norwegian patient with debilitating progressive spastic paraparesis due to intra-axial infiltration of the thoracic spinal cord. The patient had been unresponsive to interferon-alpha. Low dose vemurafenib (720 mg daily) for a period of three months resulted in significant tumor shrinkage by >60% and regression of contrast enhancement and fluorodeoxyglucose uptake on positron-emission tomography. The patient's spastic paraparesis and gait function improved dramatically. She currently walks unaided and reports a substantially improved quality of life. CONCLUSION: Our findings show that vemurafenib therapy, even at low doses, can be effective for the treatment of intra-axial central nervous system involvement in BRAF-positive Erdheim-Chester disease.

MRI characterisation of adult onset alpha-methylacyl-coA racemase deficiency diagnosed by exome sequencing.

BACKGROUND: Correct diagnosis is pivotal to understand and treat neurological disease. Herein, we report the diagnostic work-up utilizing exome sequencing and the characterization of clinical features and brain MRI in two siblings with a complex, adult-onset phenotype; including peripheral neuropathy, epilepsy, relapsing encephalopathy, bilateral thalamic lesions, type 2 diabetes mellitus, cataract, pigmentary retinopathy and tremor. METHODS: We applied clinical and genealogical investigations, homozygosity mapping and exome sequencing to establish the diagnosis and MRI to characterize the cerebral lesions. RESULTS: A recessive genetic defect was suspected in two siblings of healthy, but consanguineous parents. Homozygosity mapping revealed three shared homozygous regions and exome sequencing, revealed a novel homozygous c.367 G>A [p.Asp123Asn] mutation in the α-methylacyl-coA racemase (AMACR) gene in both patients. The genetic diagnosis of α-methylacyl-coA racemase deficiency was confirmed by demonstrating markedly increased pristanic acid levels in blood (169 µmol/L, normal <1.5 µmol/L). MRI studies showed characteristic degeneration of cerebellar afferents and efferents, including the dentatothalamic tract and thalamic lesions in both patients. CONCLUSIONS: Metabolic diseases presenting late are diagnostically challenging. We show that appropriately applied, homozygosity mapping and exome sequencing can be decisive for establishing diagnoses such as late onset α-methylacyl-coA racemase deficiency, an autosomal recessive peroxisomal disorder with accumulation of pristanic acid. Our study also highlights radiological features that may assist in diagnosis. Early diagnosis is important as patients with this disorder may benefit from restricted dietary phytanic and pristanic acid intake.

Leukoencephalopathy with brainstem and spinal cord involvement caused by a novel mutation in the DARS2 gene.

Leukoencephalopathy with brainstem and spinal cord involvement and elevated lactate (LBSL) is a rare, autosomal recessive disorder caused by mutations in the gene encoding a mitochondrial aspartyl-tRNA synthetase, DARS2. The disease is characterized by progressive spastic ataxia and magnetic resonance imaging (MRI) shows a highly characteristic leukoencephalopathy with multiple long tract involvement. We describe the clinical and radiological features of two new cases of LBSL and report a novel pathogenic mutation in the DARS2 gene. Both patients had typical clinical and radiological findings, although no elevated lactate was found. The severity of MRI changes did not correlate with clinical course and severity suggesting that, although of highly specific diagnostic value, MRI does not necessarily reflect clinical activity and should not be used to assess disease severity or prognosis in LBSL.

Adjacent level degeneration and facet arthropathy after disc prosthesis surgery or rehabilitation in patients with chronic low back pain and degenerative disc: second report of a randomized study.

STUDY DESIGN: Randomized clinical trial with 2-year follow-up. OBJECTIVE: To assess the development of adjacent level degeneration (ALD) and index level facet arthropathy (FA) in patients treated with disc prosthesis compared with patients treated with rehabilitation. SUMMARY OF BACKGROUND DATA: There is controversy about the natural history of disc degeneration and the development of ALD and FA in patients who undergo disc prosthesis surgery. METHODS: The study included 116 patients with a history of low back pain for at least 1 year, Oswestry Disability Index 30 points or more, and degenerative changes in 1 or 2 lower lumbar spine levels. Magnetic resonance imaging was performed before treatment and at the 2-year follow-up. ALD and index level FA were determined on the basis of the majority assessment of 3, independent, experienced radiologists. ALD was assessed by evaluating Modic changes, posterior high intensity zone in the disc, nucleus pulposus signal, disc height, disc contour, and FA. Data were analyzed with Fischer exact test and t test. RESULTS: ALD developed with similar frequencies in patients who were (n = 59) and were not (n = 57) treated with surgery. In patients treated with surgery, index level FA appeared or increased in 20 patients (34%) and decreased in 1 patient. In patients treated with rehabilitation, 2 (4%) had new or increased FA at the index/degenerated disc level and 1 had decreased FA (P < 0.001). The development of ALD and FA was not related to clinical outcome. CONCLUSION: In this first study that compared the courses of degeneration after treatment with disc prosthesis surgery or rehabilitation, ALD was observed at similar frequencies at the 2-year follow-up. However, the surgery group had increased FA at the implant level.

Mr morphometry analysis of grey matter volume reduction in schizophrenia: association with hallucinations.

The authors used voxel-based morphometry (VBM) to study GM volume differences in the whole brain volume between a group of patients with schizophrenia and a healthy control group. There were 12 patients and 12 control subjects. The subjects were scanned in a 1.5 T MR scanner. The patients had all been evaluated by a senior psychiatrist on the brief psychiatric rating scale (BPRS). The VBM data was correlated with reports of rate and frequency of hallucinations based on their scores on the BPRS hallucination item. There were significant grey matter volume reductions in the schizophrenia patient group in the left superior (transverse) temporal gyrus, the left middle frontal gyrus, and in the right cuneus. Areas of grey matter volume reduction that correlated negatively with hallucinations were found in the left superior (transverse) temporal gyrus, left thalamus, and left and right cerebellum. This article proposes that significant reductions in grey matter volume may be instrumental in generating spontaneous neuronal activity that is associated with speech perception experiences in the absence of an external acoustic stimulus that may cause hallucinations.