Vertebral Hemangiomas: Prevalence, new classification and natural history. magnetic resonance imaging-based retrospective longitudinal study.

BACKGROUND AND PURPOSE: To determine the prevalence of vertebral hemangiomas (VHs), establish a new classification of VHs based on their MRI-signal pattern, and study their natural history. METHODS: MRI of 1000 consecutive patients who underwent at least two MRI with an interval of at least 3 years. Growth rate and change of MRI-signal pattern during the follow-up period were the parameters included in studying the natural history of VHs. RESULTS: The prevalence of VHs was 41%. VHs were classified as type I-IV with fat-rich VHs (type I), constituted 79% of all VHs. VHs were more common among females 43% versus males 39%, p = .22. The most affected vertebra was L1. Occurrence rates for cervical (1%), thoracic (7%), and lumbar spine (10%) differed significantly (p < .001). The prevalence of VHs increased with age regardless of gender or spinal part involved (p < .001). Only 26% of VHs changed their size and 4% changed their signal during the average follow-up of 7 years. All VHs were slowly growing lesions (average expected growth of <3 mm/10 years). No significant difference between growth rate of VHs type I (0.25 mm/year) and other types of VHs. None of the VHs that were initially reported as "metastases cannot be rule out" showed alarming change in signal or size. CONCLUSIONS: VH can be classified into four types based on their MRI-signal pattern. Regardless of their type, VHs are slowly growing lesions. The presence of typical morphological pattern should enable radiologists to confidently differentiate them from vertebral metastases.

Prognosis of aphasia in stroke patients early after iv thrombolysis.

OBJECTIVE: Stroke patients with aphasia have a high long-term morbidity. Intravenous rt-PA (iv) thrombolysis is given more deliberately to these patients. Early outcome data is lacking. Aim of this study was to determine early benefit from rt-PA in patients with aphasia. METHODS: Data of stroke patients treated by iv thrombolysis was scrutinized for the presence of aphasia defined as ≥1 point for aphasia on the National Institute of Health Stroke Scale (NIHSS). Improvement was defined as a gain of ≥1 point within 24h. Cranial computed tomography (CT) scans were evaluated regarding early ischemic changes (EICs), infarct volume and localization. RESULTS: Fifty patients with aphasia were included. 16 (32%) of patients improved (4 (36%) minor, 7 (41%) moderate, 5 (23%) major stroke patients), while 44 (62%) remained unchanged. Of 28 patients with EICs, 10 (36%) improved compared to 7 out of 22 (32%) patients without (p=0.773). Aphasia outcome was significantly associated with infarct volume at admission and at 24h (Kruskal-Wallis, p=0.033, p≤0.001, respectively). CONCLUSION: EICs are not predictive of aphasia outcome and patients with improvement showed smaller infarct volumes. One third improved within 24h, while two thirds remained unchanged. This might justify a closer follow-up of aphasia in stroke patients at the acute stage.

Swirl sign in intracerebral haemorrhage: definition, prevalence, reliability and prognostic value.

BACKGROUND: Swirl sign has previously been described in epidural hematomas as areas of low attenuation, radiolucency or irregular density. The aims of this study were to describe swirl sign in ICH, study its prevalence, study the reliability of the subjective evaluation on computed tomography (CT), and to explore its prognostic value. METHODS: CTs of 203 patients with ICH were retrospectively evaluated for the presence of swirl sign. Association between swirl sign and different clinical and radiological variables was studied. RESULTS: Inter- and intraobserver agreement with regard to the occurrence of swirl sign was substantial (К 0.80) and almost perfect (К 0.87), respectively. Swirl sign was found in 30% of the study population. 61% of patients with swirl sign were dead at one month compared with 21% of those with no swirl sign (p < 0.001). Only 19% of patients with swirl sign exhibited favorable outcome at three months compared with 53% of those with no swirl sign (p < 0.001). Patients with swirl sign exhibited larger ICHs with average ICH-volume 52 ± 50 ml (median 42 ml) compared with 15 ± 25 ml (median 6) in patients whose CT did not show swirl sign (p < 0.001). Swirl sign was independent predictor of death at one month (p = 0.03; adjusted odds ratio 2.6, 95% CI 1.1 - 6), and functional outcome at three months (p = 0.045; adjusted odds ratio 2.6, 95% CI 1.02 - 6.5). CONCLUSIONS: As swirl sign showed to be an ominous sign, we recommend identification of this sign in cases of ICHs.

Early do-not-resuscitate orders in intracerebral haemorrhage; frequency and predictive value for death and functional outcome. A retrospective cohort study.

INTRODUCTION: In former studies from North America early Do-Not-Resuscitate orders (DNR orders) in patients with intracerebral haemorrhage (ICH) had negative prognostic impact on mortality. The influence of DNR orders on functional outcome and whether DNR orders are grounded on relevant patient characteristics is unknown. We aimed to determine the frequency and predictive factors of DNR-orders and its association to prognosis, in ICH patients, in Scandinavia. METHODS: In 197 consecutive ICH patients admitted to Skåne University Hospital, Malmö, Sweden, between January 2007 and June 2009, information of the presence of DNR orders within 48 hours, clinical and radiological characteristics was retrieved by review of patient medical journal and computed tomography scans. Determinants of DNR-orders, one-month case fatality and bad functional outcome (modified Rankin Scale, grade 4-6) were assessed by logistic regression analysis. RESULTS: DNR orders were made in 41% of the cases. After adjustment for confounding factors, age ≥ 75 years (Odds Ratio (95% confidence interval) 4.2(1.8-9.6)), former stroke (5.1(1.9-3.1)), Reaction Level Scale grade 2-3 and 4 (7.0(2.8-17.5) and (4.1(1.2-13.5), respectively) and intraventricular haemorrhage (3.8(1.6-9.4)) were independent determinants of early DNR orders. Independent predictors of one-month case fatality was age ≥ 75 years (3.7(1.4-9.6)) volume ≥ 30 ml (3.5(1.3-9.6)) and DNR orders (3.5(1.5-8.6)). Seizure (6.0(1.04-34.2) and brain stem hemorrhage (8.0(1.1-58.4)) were related to bad functional outcome, whereas early DNR order was not (3.5(0.99-12.7)). CONCLUSIONS: Well known prognostic factors are determinants for DNR orders, however DNR orders are independently related to one-month case fatality. In addition to improvements of the local routines, we welcome a change of attitude with an enhanced awareness of the definition of, and a more careful approach with respect to DNR orders.

Spinal epidural lipomatosis: a common imaging feature in Scheuermann disease.

STUDY DESIGN: Retrospective study. OBJECTIVES: To find out if spinal epidural lipomatosis (SEL) occurs more commonly among patients with Scheuermann disease than in the general population. SUMMARY AND BACKGROUND: On the basis of our own radiologic and operative observation, SEL seems to occur frequently in patients with Scheuermann disease. METHODS: Magnetic resonance imaging of 87 individuals (72% male, average age 19±6 y) from 2 centers (29 consecutive patients with Scheuermann disease and 58 controls) were retrospectively evaluated by 2 neuroradiologists. Spinal epidural fat (EF) at seventh thoracic vertebra (EF7), maximum EF (EFmax), dural sac diameter at T7 and at the level of maximum EF (DS7 and DSmax) were measured. EF ratios at T7 (EFR7) and at maximum EF (EFRmax) were calculated as EF/DS. Body mass index (BMI) for study population and kyphosis severity for the patients were recorded. Mann-Whitney, Spearman correlation, and χ tests were performed dependent on the variable in question. RESULTS: EF7, DS7, EFmax, EFR7, and EFRmax was significantly higher among patients with Scheuermann disease (EFmax 5.7±2.4 mm) than among controls (EFmax 3.8±1.1 mm), P<0.001. Twelve patients with Scheuermann disease (41%) fulfilled our proposed criteria for the diagnosis of SEL (EFmax>6 mm+EFRmax>0.51) compared with 2 (3%) among controls (P<0.001). Patients with Scheuermann disease exhibited higher BMI than controls (24.9±5 kg/m vs. 22.9±4 kg/m, P=0.138). Logistic regression showed that the occurrence of SEL among patients with Scheuermann disease was independent of BMI (P=0.880). The degree of kyphosis in patients with Scheuermann's disease (62±20°) was correlated to the amount of the EF. CONCLUSIONS: As SEL occurs more frequently among patients with Scheuermann disease, spine magnetic resonance imaging should be routinely performed to screen each of these patients to avoid impending neurological injury during surgery, especially in those exhibiting SEL.

Optimization of radiation exposure and image quality of the cone-beam O-arm intraoperative imaging system in spinal surgery.

STUDY DESIGN: Retrospective study. OBJECTIVES: To optimize the radiation doses and image quality for the cone-beam O-arm surgical imaging system in spinal surgery. SUMMARY OF BACKGROUND: Neurovascular compromise has been reported after screw misplacement during thoracic pedicle screw insertion. The use of O-arm with or without navigation system during spinal surgery has been shown to lower the rate of screw misplacement. The main drawback of such imaging surgical systems is the high radiation exposure. METHODS: Chest phantom and cadaveric pig spine were examined on the O-arm with different scan settings: 2 were recommended by the O-arm manufacturer (120 kV/320 mAs, and 120 kV/128 mAs), and 3 low-dose settings (80 kV/80 mAs, 80 kV/40 mAs, and 60 kV/40 mAs). The radiation doses were estimated by Monte Carlo calculations. Objective evaluation of image quality included interobserver agreement in the measurement of pedicular width in chest phantom and assessment of screw placement in cadaveric pig spine. RESULTS: The effective dose/cm for 120 kV/320 mAs scan was 13, 26, and 69 times higher than those delivered with 80 kV/80 mAs, 80 kV/40 mAs, and 60 kV/40 mAs scans, respectively. Images with 60 kV/40 mAs were unreliable. Images with 80 kV/80 mAs were considered reliable with good interobserver agreement when measuring the pedicular width (random error 0.38 mm and intraclass correlation coefficient 0.979) and almost perfect agreement when evaluating the screw placement (κ value 0.86). CONCLUSIONS: The radiation doses of the O-arm system can be reduced 5 to 13 times without negative impact on image quality with regard to information required for spinal surgery.

Hyperdense middle cerebral artery sign in multidetector computed tomography: definition, occurrence, and reliability analysis.

BACKGROUND: The hyperdense middle cerebral artery sign (HMCAS) is one of the early changes seen on the computed tomography in acute ischemic stroke of MCA territory. AIMS: To evaluate the reliability of subjective evaluation of HMCAS on CT performed at multidetector CT (MDCT) and evaluated in the Picture Archiving Communication Systems, to define objective criteria for HMCAS and to find out if there are any predictors for the occurrence of HMCAS. MATERIALS AND METHODS: CTs of 121 consecutive patients (mean age of 70 years) treated with thrombolytic therapy were retrospectively evaluated by two neuroradiologists both subjectively and objectively with respect to HMCAS. RESULTS: HMCAS was subjectively found in 32% of study population. The interobserver and intraobserver agreement were substantial (K value of 0.69 and 0.80, respectively) and increased to almost perfect (K value of 0.86) when the reader provided with clinical information. The HMCAS was found twice as often in male patients. Patients with HMCAS were three years younger than those whose baseline CT did not show HMCAS. A 100% sensitivity achieved when objective criteria were defined as combination of MCA attenuation >or= 46 HU and MCA ratio > 1.2 (using oval ROIs) and MCA attenuation >or= 50 HU and MCA ratio of > 1.4 (using pixel sized ROIs). CONCLUSION: Performing CT examinations on MDCT and assessment of the images in PACS might have contributed to improvement of the reliability of evaluating HMCAS on CT by enabling an objective evaluation of this sign with measurements of attenuation value in the course of MCA using oval or pixel sized ROIs as well as estimation of MCA ratio.