Post-mortem CT in the investigation of homicides.

AIM: To investigate the reliability of post-mortem computed tomography (PMCT) in a case series of homicides involving blunt-force, sharp-force, and ballistic trauma. MATERIALS AND METHODS: The study investigates 16 homicide cases that underwent PMCT before autopsy. Two radiologists assessed the PMCT examinations and the data were compared to the forensic pathology findings. Data were organised in broad categories: foreign bodies, external injuries, soft-tissue and organ injuries, fractures, air in cavities, fluid collections, random pathology, and wound track. Findings were organised by systems: head and neck, thorax, abdomen and pelvis, extremities. Cohen's kappa statistics were used to assess observer agreement. RESULTS: Six gunshot-related homicides (37.5%), seven sharp-force-related homicides (43.75%), two blunt-force-related deaths (12.5%), and one homicide due to mechanical asphyxia (1.25%) were analysed. A total of 64 fractures were reported by the pathologists, 67 by radiologist 1 and 68 by radiologist 2. Agreement was deemed substantial in all cases. Pathologists failed to report gas in cavities while radiologists underreported superficial injuries. CONCLUSION: An overall observation was that less accurate findings were produced by the blinded radiologist in comparison to the non-blinded one. The extremeness of homicides obscured the interpretation of PMCT leading to the observed discrepancies. The combination of PMCT and autopsies is deemed optimal when investigating homicidal events.

Restoration of the degenerated cervical intervertebral space: how much should we distract? A magnetic resonance imaging study.

The aim of the study was to quantify normal cervical disc space measurements and to generate a normal values' database. Furthermore, during operative restoration of a degenerated intervertebral disc, it is difficult to calculate the amount of distraction required to restore the collapsed space to its normal height. A secondary purpose is personalizing the anatomical correction. Therefore, we expressed disc height based on measurements of its neighboring disc as an equation, by using simple linear regression. We reviewed MRI studies from asymptomatic healthy subjects (16 men-24 women, mean age 27.25 years). We measured midsagittal anterior, middle and posterior vertebral body and disc height, and disc diameter from C3 to T1 vertebra. We calculated mean disc height, disc height index (DHI) and disc convexity index per spinal level. C6-7 mean and anterior disc height were significantly greater than all respective measurements, except C5-6 (p<0.01). Middle C6-7-disc height was significantly greater compared to respective measurements in every other level (p<0.01). C5-6, C6-7 and C7-T1 mean disc height is significantly greater in men. Middle disc height is the greatest among disc heights in every spinal level. DHI does not differ between sexes, it increases from C3-4 to C5-6 with a slight decrease in C6-7, while its value significantly decreases in C7-T1 (p<0.0001). These measurements could be used for anatomical, individualized restoration of the degenerated intervertebral disc; thus, avoiding overdistraction. Our data could improve preoperative templating or implant design.

Abdominal fat volume estimation by stereology on CT: a comparison with manual planimetry.

OBJECTIVES: To deploy and evaluate a stereological point-counting technique on abdominal CT for the estimation of visceral (VAF) and subcutaneous abdominal fat (SAF) volumes. METHODS: Stereological volume estimations based on point counting and systematic sampling were performed on images from 14 consecutive patients who had undergone abdominal CT. For the optimization of the method, five sampling intensities in combination with 100 and 200 points were tested. The optimum stereological measurements were compared with VAF and SAF volumes derived by the standard technique of manual planimetry on the same scans. RESULTS: Optimization analysis showed that the selection of 200 points along with the sampling intensity 1/8 provided efficient volume estimations in less than 4 min for VAF and SAF together. The optimized stereology showed strong correlation with planimetry (VAF: r = 0.98; SAF: r = 0.98). No statistical differences were found between the two methods (VAF: P = 0.81; SAF: P = 0.83). The 95% limits of agreement were also acceptable (VAF: -16.5%, 16.1%; SAF: -10.8%, 10.7%) and the repeatability of stereology was good (VAF: CV = 4.5%, SAF: CV = 3.2%). CONCLUSIONS: Stereology may be successfully applied to CT images for the efficient estimation of abdominal fat volume and may constitute a good alternative to the conventional planimetric technique. KEY POINTS: Abdominal obesity is associated with increased risk of disease and mortality. Stereology may quantify visceral and subcutaneous abdominal fat accurately and consistently. The application of stereology to estimating abdominal volume fat reduces processing time. Stereology is an efficient alternative method for estimating abdominal fat volume.

Hemodynamic evidence linking cognitive deficits in clinically isolated syndrome to regional brain inflammation.

BACKGROUND AND PURPOSE: To investigate the relation between hemodynamic measurements and memory function in patients with clinically isolated syndrome (CIS). METHODS: Forty CIS patients were administered tests of verbal short-term/working memory and passage learning. Using dynamic susceptibility contrast MRI cerebral blood volume (CBV), cerebral blood flow and mean transit time values were estimated in 20 cerebral regions of interest, placed in normal appearing white matter (NAWM) and normal appearing deep gray matter structures, bilaterally. RESULTS: CIS patients showed significantly impaired scores on working memory and secondary verbal memory that correlated inversely with elevated CBV values in the left frontal and periventricular NAWM, thalamus, right caudate and corpus callosum. CONCLUSIONS: Verbal memory in CIS correlates inversely with elevated CBV values of brain structures involved in memory. As these hemodynamic changes, detected in CIS, are indicative of inflammation, the observed cognitive disturbances may relate to widespread brain inflammatory processes that prevail in early multiple sclerosis.

The gymnasts' hip and groin: a magnetic resonance imaging study in asymptomatic elite athletes.

OBJECTIVE: Specific patterns of developmental adaptation of the proximal femur have been recognized in some sports. Gymnastics are characterized by repetitive axial loading and hip rotations in combination with extreme hip positions. It is unknown how and if these forces can affect an immature skeleton in the long term. We sought to evaluate this, by means of magnetic resonance imaging of the hip and groin of such elite asymptomatic athletes. MATERIALS AND METHODS: We performed a case-control comparative MR imaging study of both hips and groin of 12 (7 male, 5 female) skeletally mature young (mean age 18.6 years) asymptomatic international level gymnasts with a minimum of 10 years' training with age-matched non-athletes. At the time of recruitment, none of the athletes had a recorded musculoskeletal complaint or injury in the anatomical area around the hip. RESULTS: The study showed that elite gymnasts share four common morphological characteristics on MRI that deviate from normal and are considered to be the result of adaptational changes to the specific sport: high centre-column-diaphysis angle (coxa valga140° on average), ligamentum teres hypertrophy, friction of the iliotibial band with oedema surrounding the greater trochanter, and a high incidence (62.5 %) of radiological appearances of ischiofemoral impingement. CONCLUSION: Our study showed that elite gymnasts share four common morphological characteristics on MRI that deviate from normal. These findings were in asymptomatic subjects; hence, radiologists and sports physicians should be aware of them in order to avoid unnecessary treatment.

Age estimation based on the metamorphosis of the clavicle end: A test of Falys and Prangle method in two contemporary samples.

Upon finding skeletal unidentified remains, four are the questions that must be answered: age, sex, ancestry, and stature. Regarding age estimation, clavicle has received special attention because medial epiphysis is the last epiphysis, among long bones that ossifies. Falys and Prangle proposed a method of age estimation based on three degenerative characteristics-surface topography (TOP), Porosity (POR) and Osteophyte formation (OST)-evaluated on the sternal end of the clavicle according to the descriptions and the illustrations provided in the original article producing satisfactory results. The current study aims to test the applicability of the Falys' and Prangle's method on 174 individuals from two contemporary samples, one from Greece (Cretan osteological Collection and Athens Forensic Anthropology Lab collection) and one from Thailand (Osteological collection in Chiang Mai). Composite scores were calculated, inter and intra- observer error were estimated by kappa statistics and regression equations of the original study were tested in our sample and in subsamples divided by sex and population. The Greek sample gave more accurate estimates compared to the Thai sample. Regressions of known sex gave slightly better results in most cases. When individuals <40 years old were excluded, classification increased for both Thai and Greeks. The results of this pilot study indicate that there are morphological features on the clavicle that are highly correlated with age. Thus, there is a scope of expanding research on the morphological features of the collar bone.

Pediatric radiation dose and risk from bone density measurements using a GE Lunar Prodigy scanner.

UNLABELLED: Effective radiation doses associated with bone mineral density examinations performed on children using a GE Lunar Prodigy fan-beam dual-energy X-ray absorptiometry (DXA) scanner were found to be comparable to doses from pencil-beam DXA devices, i.e., lower than 1 µSv. Cancer risks associated with acquisitions obtained in this study are negligible. INTRODUCTION: No data were found in the literature on radiation doses and potential risks following pediatric DXA performed on GE Lunar DXA scanners. This study aimed to estimate effective doses and associated cancer risks involved in pediatric examinations performed on a GE Lunar Prodigy scanner. METHODS: Four physical anthropomorphic phantoms representing newborn, 1-, 5-, and 10-year-old patients were employed to simulate DXA exposures. All acquisitions were carried out using the Prodigy scanner. Dose measurements were performed for spine and dual femur using the phantoms simulating the 5- and 10-year-old child. Moreover, doses associated with whole-body examinations were measured for the four phantoms used in the current study. RESULTS: The gender-average effective dose for spine and hip examinations were 0.65 and 0.36 µSv, respectively, for the phantom representing the 5-year-old child and 0.93 and 0.205 µSv, respectively, for the phantom representing the 10-year-old child. Effective doses for whole-body examinations were 0.25, 0.22, 0.19, and 0.15 µSv for the neonate, 1-, 5-, and 10-year old child, respectively. The estimated lifetime cancer risks were negligible, i.e., 0.02-0.25 per million, depending on the sex, age, and type of DXA examination. A formula is presented for the estimation of effective dose from examinations performed on GE Lunar Prodigy scanners installed in other institutions. CONCLUSIONS: The effective doses and potential cancer risks associated with pediatric DXA examinations performed on a GE Lunar Prodigy fan-beam scanner were found to be comparable to doses and risks reported from pencil-beam DXA devices.

Effect of two sitting postures on lumbar sagittal alignment and intervertebral discs in runners.

PURPOSE: We evaluated in vivo changes in lumbar lordosis and intervertebral discs in runners and assessed the relationship between these changes and degenerative disc disease in runners with and without a history of low back pain. MATERIALS AND METHODS: Using open upright magnetic resonance (MR) imaging, we prospectively studied changes in lumbar lordosis and intervertebral discs of 25 elite long-distance runners in two sitting postures (neutral and extended) before and after 1 h of running and compared the results with disc height and dehydration/degeneration. Seventeen of the 25 runners had a history of low back pain. RESULTS: After 1 h of running, mean lordosis in neutral posture reduced by 4°; reduction was significant in runners with a history of low back pain. A significant reduction in mean lordosis in extension was not observed. Mean disc height significantly reduced in both postures, without, however, any statistical significance between runners with and without a history low back pain in any posture. Variable degrees of disc dehydration/degeneration were observed in 23 runners (57 discs), more commonly at L5-S1. A significant difference of disc dehydration/degeneration between runners with and without a history of low back pain was not observed. CONCLUSIONS: Intervertebral discs undergo significant strain after 1 h of running that in the long term may lead to low back pain and degenerative disc disease. Runners, especially those with low back pain and degenerative disc disease, should be evaluated after training to preserve the normal lumbar lordosis.

MRI diffusion phantoms: ADC and relaxometric measurement comparisons between polyacrylamide and agarose gels.

PURPOSE: The aim of this study is to compare polyacrylamide and agarose gels, as components of a simple MRI phantom, for the measurements of Apparent Diffusion Coefficient (ADC), T1 and T2 relaxation times. MATERIALS AND METHODS: Five (5) test tubes with polyacrylamide gels of different monomer concentrations and six (6) test tubes of different agarose gel concentrations were used as a phantom for ADC, T1 and T2 measurements, which were expressed as 2D color parametric maps, on a 1.5 T clinical MRI system. ADC and T2 maps were calculated utilizing a Weighted Linear (WL) regression fitting algorithm. T1 maps were calculated utilizing a standard non-linear fitting algorithm. RESULTS: In agarose gels, ADC measurements are independent of the agarose concentration, whereas the T1 and T2 relaxation times decrease with increasing agarose concentration. On the contrary, in polyacrylamide gels, ADC measurements decrease quadratically while increasing the monomer concentration, whereas the T1 and T2 relaxation times reveal a linear decrease with increasing monomer concentration. CONCLUSION: Polyacrylamide gels can serve as a better means for simulating ADC values, as compared with the agarose gels used in this study.

Calcitonin effect on Achilles tendon healing. An experimental study on rabbits.

OBJECTIVE: A positive potential effect of Calcitonin (CT) on Achilles tendon healing was investigated as well as the ability of MRI to follow the tendon healing process. MATERIALS AND METHODS: A standardized tenotomy of the Achilles tendon was performed on forty-two rabbits. Twenty-one animals received daily 21 IU /kg Calcitonin intramuscularly (treatment group CT) during the experiment and the remaining received saline solution (control group P). Seven animals from each group were killed at one, two and three weeks postoperatively. All animals had serial MRI scans and tendon samples underwent biomechanical and histological testing. RESULTS: For both groups, animals of the same subgroup showed statistically significant difference in signal intensity values of MRI between the 1st and 3rd week (p<0.001) and between the 2nd and 3rd week (p<0.001). Signal intensity values of MRI didn't show any differences between animals under treatment and controls measured at 1st (p=0.23), 2nd (p=0.23) and 3rd (p=0.53) postoperative week. Tendon samples from group CT showed statistically significant difference in ultimate tensile strength compared to controls at 2 (p<0,0005) and 3 (p<0,0005) weeks post-surgery. Histology showed a positive Calcitonin effect at all tendon healing stages. CONCLUSION: It is suggested that Calcitonin enhances Achilles tendon healing process.

Alpha-1 antichymotrypsin gene signal peptide a/t polymorphism and primary intracerebral hemorrhage.

BACKGROUND/AIMS: Alpha-1 antichymotrypsin (ACT), a serine proteinase inhibitor, has been implicated in vascular pathology. The TT genotype of the ACT signal peptide A/T polymorphism has been reported to confer susceptibility to primary intracerebral hemorrhage (PICH). We conducted a prospective study to test possible association of ACT signal peptide A/T polymorphism with PICH in a Greek cohort with enough power (80%) to detect a twofold increase in the odds ratio. METHODS: We prospectively recruited 147 patients with PICH. ACT signal peptide A/T genotypes were determined in patients and 206 healthy, age- and sex-matched control subjects from the neurology outpatient clinic using the polymerase chain reaction restriction fragment length polymorphism method. RESULTS: Our study did not show an association between ACT signal peptide A/T polymorphism and PICH. We also failed to find any influence on age at onset, the location and volume of PICH as well as on clinical severity at admission or 6-month outcome. CONCLUSION: Our data failed to confirm an association between ACT signal peptide A/T polymorphism and PICH. However, we cannot exclude the possibility that the TT genotype confers susceptibility at less than a twofold increase.

The impact of spin coupling signal loss on fat content characterization in multi-echo acquisitions with different echo spacing.

PURPOSE: This study aimed to assess the effect of echo spacing in transverse magnetization (T2) signal decay of gel and fat (oil) samples. Additionally, we assess the feasibility of using spin coupling as a determinant of fat content. METHODS: Phantoms of known T2 values, as well as vegetable oil phantoms, were scanned at 1.5T scanner with a multi echo FSE sequence of variable echo spacing above and below the empirical threshold of 20ms for echo train signal modulation (6.7, 13.6, 26.8, and 40ms). T2 values were calculated from monoexponential fitting of the data. Relative signal loss between the four acquisitions of different echo spacing was calculated. RESULTS: Agreement in the T2 values of water gel phantom was observed in all acquisitions as opposed to fat phantom (oil) samples. Relative differences in signal intensity between two successive sequences of different echo spacing on composite fat/water regions of interest was found to be linearly correlated to fat fraction of the ROI. CONCLUSION: The sample specific degree of signal loss that was observed between different fat samples (vegetable oils) can be attributed to the composition of each sample in J coupled fat components. Hence, spin coupling may be used as a determinant of fat content.

Imaging findings in a case of stand up paddle surfer's myelopathy.

Stand up paddle (SUP) surfing, a variant of ocean surfing, is becoming very popular because it can be performed at any level of difficulty and thus attracts athletes from a wide range of ages. Unlike ocean surfing, limited data exist on injuries related to SUP surfing. We report the first case of a 28-year-old athlete who developed myelopathy during his first SUP surfing session. Clinical examination revealed severe neurological deficit, which had not subsided fully at the 28-month follow-up.

Electron density of tissues and breast cancer radiotherapy: a quantitative CT study.

PURPOSE: To obtain more accurate data on the electron density of tissues to be used in the treatment planning of breast cancer patients. METHODS AND MATERIALS: Single kVp quantitative computed tomography was applied in 70 women, 20 to 77 years old, to study the electron density of the breast, the thoracic wall close and parallel to the breast, and the lung parenchyma. RESULTS: The electron density of the entire breast decreases with increasing age in premenopausal women and remains practically constant in postmenopausal women (8% less than that of water). No difference was found in the electron densities of the right and left breast. The electron density of the lung parenchyma in proximity to the breast is lower than the density in the entire lung parenchyma. CONCLUSIONS: Whenever no accurate data is available on individual patients, the electron density values to be used in treatment planning for breast and thoracic wall have to take into account both age and menstrual status. The regional differences in electron density of the lung also have to be considered.

Tremolite whitewashing and pleural calcifications.

Radiologic screening of 688 inhabitants of the Metsovo area in Northwest Greece revealed that 323 (46.9 percent) had pleural calcifications. The percentage of positive examinations rose with age. Calcifications were observed in all four villages of the area where a material ("luto" soil) had been extensively used for whitewashing until 1940 to 1950. In four other villages in the immediate vicinity, where "luto" had never been used, pleural calcifications were not observed. Results suggest that Metsovo tremolite may have caused pleural calcifications to all individuals born in Metsovo before 1940. This is the first study indicating that environmental asbestos exposure can cause abnormalities in everyone exposed to it.

A phase II trial of carboplatin and vindesine in patients with non-small cell lung cancer. A Hellenic Cooperative Oncology Group study.

In an effort to investigate a regimen less toxic and more convenient than cisplatin combinations, 50 patients with non-small cell lung cancer (NSCLC) were treated in a Phase II study with carboplatin and vindesine. Carboplatin 300 mg/m2 every 28 days and vindesine 3 mg/m2 every 2 weeks were administered on an outpatient basis. Eight patients had a partial response of their disease (16%, confidence limits 7-29%). Mean duration of response was 4.5+ months (1 +/- 8). Toxicity, mainly of grade I-II, was noticed in 4-28% of the patients. The most common side effect was mild to moderate leukopenia (28%). The combination of carboplatin and vindesine at the above doses was very well tolerated. Although the response rate was relatively low, the survival in this patient population was similar to other cisplatin-containing regimens.

Bone mineral status after renal transplantation. Assessment by noninvasive techniques.

RATIONALE AND OBJECTIVES: Bone mineral status in recipients of renal grafts is related to preexisting renal osteodystrophy and immunosuppressive treatment. The authors assessed bone mineral status after renal transplantation. METHODS: Bone mineral status of 20 male graft recipients was evaluated using the following noninvasive techniques: 1) neutron activation analysis, to measure hand bone phosphorus (HBP); 2) single photon absorptiometry, to measure forearm bone mineral content (BMC); and 3) single energy spectrum quantitative computed tomography, to measure spinal trabecular bone equivalent density (TBED). RESULTS: The mean (+/- SD, P) HBP, BMC, and TBED were found to be respectively, 4.8% (+/- 8.3%, P = .02), 6.6% (+/- 14.6%, P = .07) and 52% (+/- 8.5%, P < .001) lower than that measured in matched normal controls. Renal graft recipients demonstrated mean HBP and BMC decrements that were similar to those observed in matched patients on extrarenal dialysis, although the decrement in TBED was significantly greater in the graft recipients (P < .001). Repeated measurements performed during a 3-year period showed no statistically significant changes. CONCLUSIONS: Renal transplantation was associated with minor degree of osteopenia in the primarily cortical bone tissue. We speculate that the remarkably low TBED values in graft recipients does not reflect a mean 52% decrement of spinal bone minerals, but rather may be attributed in part to the deposition of adipose tissue in the spine as a result of corticosteroid treatment.

Comparison of T1-weighted spin-echo and 3D T1-weighted multi-shot Echo Planar pulse sequences in imaging the brain at it.

The purpose of this study was to evaluate the ability of three dimensional T1-weighted multi-shot Echo Planar Imaging (3D T1w EPI) MR pulse sequence to provide comparable to T1w Spin Echo (SE) results in various diseases of the brain, during shorter acquisition times. Thirty-six patients (aged 30-74 years) with various indications were included in the study. All examinations were performed with a 1T MR scanner with a maximum gradient strength of 15 mT/m. The SE sequence lasted 3 min 50s and the 3D T1w EPI 59s. The quantitative analysis included number of enhancing lesions, signal-to-noise ratio of the enhancing lesions and contrast-to-noise ratio (CNR) between enhancing lesions and white matter in both sequences before and after i.v. administration of 0.1 mmol/kg gadopentetate dimeglumine. In addition, the percentage increase of enhancement was measured in each lesion of each sequence. The qualitative analysis included a) conspicuity of the lesions and b) presence of artifacts. The T1w SE sequence was significantly better compared to 3D T1w EPI in all quantitative measurements with the exception of CNR of enhancing lesions before contrast administration and the percentage enhancement. The conspicuity of the lesions did not differ between the two sequences. The EPI sequence presented with significantly more artifacts. We conclude that the 3D T1w EPI sequence could not be used instead of the conventional T1w SE, in routine imaging of the brain. Its overall diagnostic capability, could be useful only in uncooperative patients.

Magnetic resonance cholangiopancreatography: comparison between respiratory-triggered turbo spin echo and breath hold single-shot turbo spin echo sequences.

The purpose of this study was to compare the relative conspicuity of the pancreaticobiliary tree on respiratory-triggered three-dimensional turbo spin echo (3D TSE RT) and breath hold single-shot turbo spin echo (SSTSE BH) acquisitions respectively in MRCP imaging. Both techniques were applied to 61 patients with clinically suspected pancreaticobiliary disease using a 1.0 T MR system. All images were reviewed blindly. Qualitative comparison was made by grading subjectively the conspicuity of extrahepatic, intrahepatic, and main pancreatic ducts. Quantitative comparison included calculations of signal-to-noise ratio of the common bile duct, main pancreatic duct, gallbladder, liver, and contrast-to-noise ratio, relative contrast between common bile duct, gallbladder, and liver. 3D TSE RT provided significantly higher signal-to-noise ratio of the common bile duct (mean value 163.19) and main pancreatic duct (mean value 95.37) compared to SSTSE BH (mean values 76.24 and 26.22, respectively). 3D TSE RT was inferior to SSTSE BH for the depiction of intrahepatic ducts and pancreatic duct (head portion). 3D TSE RT and SSTSE BH sequences provide complimentary information in the visualization of the biliary and pancreatic ducts. Further comparative clinical studies are needed to redefine the sensitivity, specificity, and accuracy of MRCP using both sequences.

Quantitative computed tomography for bone mineral measurement: technical aspects, dosimetry, normal data and clinical applications.

A single KVp quantitative CT (QCT) technique was used for measuring the spinal trabecular bone density. The trabecular bone equivalent density (TBED) was expressed as the density of a K2HPO4 solution that exhibits a linear attenuation coefficient identical to that of trabecular bone. A field non-uniformity correcting factor was obtained from experiments on phantoms. The effective equivalent dose of the whole examination (four sections and a scout view) is 370 muSv. The in vivo short-term precision (reproducibility coefficient of variation) ranges from 1.4% to 4.1% depending on the TBED values of the normal subjects. The TBED was measured in 206 normal Greeks aged 30-69 years. Average TBED decreased with increasing age for both sexes. Analysis considering separately each vertebra showed a tendency to a caudal spinal TBED reduction. No correlation was found between the TBED values and the body habitus, milk consumption, smoking habits in men, and number of full-term pregnancies. A significant difference (p less than 0.01) was found between the TBED values of the normals and those of 50 women suffering from post-menopausal osteoporosis, 37 alcoholic men, and 12 gastrectomized men (Billroth II). Quantitative CT has been established as a method of measuring TBED in health and disease, and the results from this study confirm these applications.