Kaposiform haemangioendothelioma of the spine associated with fixed hyperlordotic deformity and Kasabach-Merritt Syndrome: a case report and literature review.

Kaposiform haemangioendothelioma (KHE) is a rare childhood disease classified by the International Society for the Study of Vascular Anomalies (ISSVA) as a locally aggressive vascular tumor. It has been reported to affect any site, with a predilection for the extremities and trunk. Although it typically manifests as an enlarging cutaneous or soft tissue lesion, less than 10% of cases have no skin involvement, with the retroperitoneum being the most frequently involved extracutaneous site. Approximately twenty cases of KHE with bony involvement have been reported in the literature to date, with only five of those cases involving the spine specifically.We present a, rare case of KHE who presented with progressive fixed hyperlordotic deformity, multiple non-specific spinal lesions, and abnormal blood tests, posing a clinical and radiological diagnostic challenge. Additionally, we conducted a thorough review of the literature to compare and contrast the various multimodality imaging manifestations of KHE involving the spine.

MRI of the cervical spine with 3D gradient echo sequence at 3 T: initial experience.

AIM: The aim of this study was to compare three-dimensional (3D) high resolution T2*-weighted gradient echo (3D FFE) magnetic resonance (MR) sequence with conventional 2D T2-weighted turbo spin echo (TSE) MR sequence for imaging of the cervical spine, especially to assess the detectability of the internal anatomy of the cervical spinal cord, i.e. to distinguish the grey and white matter. METHODS: Fifteen volunteers were examined at 3.0T MR unit. Signal-to-noise (SNR), contrast-to-noise (CNR) and image homogeneity were evaluated. In the visual analysis, the visibility of anatomical structures of the cervical spine and artifacts were assessed. The nonparametric method of paired sample t-test was adopted to evaluate the differences between the sequences. RESULTS: The 3D FFE sequence provided better results for CNR, cerebrospinal fluid (CSF) versus white matter, grey matter, disk and bone. Moreover, it yielded good results for the CNR grey matter versus white matter. The butterfly-shaped "H" is clearly displayed in the 3D FFE sequence. The statistical analysis revealed the statistically significant difference between the 2D TSE and 3D FFE sequences for the contrast of CSF versus spinal cord (both grey matter and white matter). CONCLUSION: The 3D FFE sequence in MR imaging of the cervical spinal cord is superior in delineation of spinal cord anatomical structures compared to 2D TSE sequence.

Frequency of developmental dysplasia of the hip in breech-presented Chinese neonates in Hong Kong.

OBJECTIVES. To clarify the use of ultrasonography by determining the frequency of developmental dysplasia of the hip among breech-presented Chinese neonates in Hong Kong. DESIGN. Prospective case series. SETTING. Regional hospital, Hong Kong. PATIENTS. All breech-presented Chinese neonates born during January 2008 to June 2009 were included (except premature neonates). They were examined clinically from birth till the age of 1 year. Ultrasound of the hips was performed at the age of 2 weeks, and X-ray of the pelvis at the age of 1 year. RESULTS. A total of 209 breech-presented neonates were born during the study period; 110 neonates completed all necessary investigations and follow-up. Among the latter, there were three neonates with developmental dysplasia of the hip warranting treatment, which amounted to a frequency of 2.7%. CONCLUSION. Developmental dysplasia of the hip among breech-presented Chinese babies is only slightly less common than in corresponding populations in other regions in the world. Since early diagnosis is important, ultrasonography screening in high-risk cases such as those with breech presentation may be useful.

Optimal timing for the administration of intranasal dexmedetomidine for premedication in children.

Previous studies have shown that 1 µg.kg(-1) intranasal dexmedetomidine produces significant sedation in children aged between 2 and 12 years. This investigation was designed to evaluate the onset time. One hundred children aged 1-12 years of ASA physical status 1-2 undergoing elective surgery were randomly allocated to five groups. Patients in groups A to D received intranasal dexmedetomidine 1 µg.kg(-1) . Patients in Group E received intranasal placebo (0.9% saline). Children from groups A, B, C, D and E had intravenous cannulation attempted at 30, 45, 60, 75 and 45 min respectively after intranasal drug or placebo administration. Vital signs, behaviour and sedation status of the children were assessed regularly until induction of anaesthesia. More children from groups A to D achieved satisfactory sedation at the time of cannulation when compared to group E (p < 0.001). The proportion of children who achieved satisfactory sedation was not significantly different among groups A to D. Overall 62% of the children who received intranasal dexmedetomidine had satisfactory sedation at the time of cannulation. The median (95% CI) time for onset of sedation was 25 (25-30) min. The median (95% CI) duration of sedation was 85 (55-100) min.

Antimicrobial activity of Chinese medicine herbs against common bacteria in oral biofilm. A pilot study.

Twenty traditional Chinese medicines (TCM) were evaluated for their antimicrobial activity against four common oral bacteria. TCMs were tested for sensitivity against Streptococcus mitis, Streptococcus sanguis, Streptococcus mutans and Porphyromonas gingivalis. Aliquots of suspension of each bacterial species were inoculated onto a horse blood agar plate with TCMs soaked separately on 6mm paper disks. The plates were incubated for 48h anaerobically and the mean diameters of growth inhibition of three different areas obtained. 0.2% (w/v) chlorhexidine was used as a positive control. Broth microdilution assay was used to determine minimum inhibitory concentration and minimum bactericidal concentration. Fructus armeniaca mume was effective against all four bacteria. Thirteen TCMs demonstrated antimicrobial activity against Porphyromonas gingivalis, including Cortex magnoliae officinalis, Cortex phellodendri, Flos caryophylli, Flos lonicerae japonicae, Fructus armeniaca mume, Fructus forsythiae suspensae, Herba cum radice violae yedoensitis, Herba menthae haplocalycis, Pericarpium granati, Radix et rhizoma rhei, Radix gentianae, Ramulus cinnamomi cassia and Rhizoma cimicifugae. Cortex phellodendri showed antimicrobial activity against Streptococcus mutans, while Radix et rhizoma rhei was effective against Streptococcus mitis and Streptococcus sanguis. Fructus armeniaca mume had inhibitory effects against Streptococcus mitis, Streptococcus sanguis, Streptococcus mutans and Porphyromonas gingivalis in vitro.

3D time of flight MR angiography: acquisition with small field of view and low phase encodes.

The aim of the study was to evaluate and compare the image quality of the 3D TOF MRA acquired with a small FOV and low phase encodes with those MR angiographic images acquired with standard pulse sequence parameters. Twenty patients who were referred to our institution for MR imaging of the brain and strictly satisfied the selection criteria were included in this study. Apart from the routine protocol for MR imaging of the brain, 3D TOF MRA of the circle of Willis with a small FOV and a standard FOV were performed. The image quality of all MRA was evaluated by two independent observers who were blind to the pulse sequence parameters. From the standard FOV MRA, 22.5, 12.5, and 5% of the patients were graded as mild, moderate, and severe stenosis of the internal carotid artery, respectively. On the contrary, no apparent stenosis was observed from the small FOV MRA with low phase encodes. Regarding the reduction in MR artifacts and acquisition time achieved with the small FOV 3D TOF MRA with low phase encodes, this might be a useful MR angiographic technique to be used in routine clinical practice.

Diffuse axonal injury: detection of changes in anisotropy of water diffusion by diffusion-weighted imaging.

Myelinated axons of white matter demonstrate prominent directional differences in water diffusion. We performed diffusion-weighted imaging on ten patients with head injury to explore the feasibility of using water diffusion anisotropy for quantitating diffuse axonal injury. We showed significant decrease in diffusion anisotropy indices in areas with or without signal abnormality on T2 and T2*-weighted images. We conclude that the water diffusion anisotropy index a potentially useful, sensitive and quantitative way of diagnosing and assessing patients with diffuse axonal injury.

Digital subtraction in gadolinium-enhanced MR imaging of the brain: a method to reduce contrast dosage.

The aim of the study was to investigate the feasibility of using digital subtraction in contrast-enhanced MR imaging of the brain to reduce the MR contrast dosage without jeopardizing patient care. Fifty-two patients with intracranial lesions, either intra-axial or extra-axial, detected by computerized tomography were selected for contrast-enhanced MR imaging with half-dose and full-dose of gadopentetate dimeglumine. The half-dose unsubtracted, full-dose unsubtracted, and half-dose subtracted MR images were visually assessed by counting the number of enhancing brain lesions in the images and quantitatively analyzed by computing their lesion contrast-to-background ratios (CBR). The visual conspicuity of the half-dose subtracted MR images was comparable to that of the full-dose unsubtracted MR images ( p>0.05), whereas the CBR of the half-dose subtracted images was approximately two to three times higher than that of the full-dose unsubtracted images. The half-dose subtracted T1-weighted spin-echo images might be able to replace the conventional standard-dose T1-weighted spin-echo images in MR imaging of the brain.

Subacute hepatic failure after the perinatal period with haemochromatotic siderosis at the age of 11 months: an unusual perspective on neonatal haemochromatosis.

UNLABELLED: Neonatal haemochromatosis is a rare disease characterized by the early onset of liver failure, a rapidly deteriorating clinical course and high mortality. An unusual case is presented of subacute hepatic failure in which autopsy findings at the age of 11 mo showed a haemochromatotic pattern of siderosis. Despite the similarity in the pattern of iron distribution to neonatal haemochromatosis, the clinical course was highly atypical in that the infant had later and milder presentation at 1 mo of age and slow progression into liver failure. This case illustrates the heterogeneous nature of the haemochromatotic phenotype in newborns and infants. CONCLUSION: The entity "neonatal haemochromatosis" may reflect a spectrum of diseases with diverse aetiologies. Fulminant liver disease in the newborn period can also result in similar pattern of iron distribution.

Acute vertebral body compression fractures: discrimination between benign and malignant causes using apparent diffusion coefficients.

Diffusion weighted MRI was performed on patients with acute vertebral body compression. The usefulness of the apparent diffusion coefficient (ADC) in differentiating between benign and malignant fractures was evaluated. A total of 49 acute vertebral body compression fractures were found in 32 patients. 25 fractures in 18 patients were due to osteoporosis, 18 fractures in 12 patients were histologically proven to be due to malignancy, and 6 fractures in 2 patients were due to tuberculosis. Signal intensities on T(1) weighted, short tau inversion recovery (STIR) and diffusion weighted images were compared. ADC values of normal and abnormal vertebral bodies were calculated. Except for two patients with sclerotic metastases, benign acute vertebral fractures were hypointense and malignant acute vertebral fractures were hyperintense with respect to normal bone marrow on diffusion weighted images. Mean combined ADCs (ADC(cmb); average of the combined ADCs in the x, y and z diffusion directions) were 0.23 x 10(-3) mm(2) s(-1) in normal vertebrae, 0.82 x 10(-3) mm(2) s(-1) in malignant acute vertebral fractures and 1.94 x 10(-3) mm(2) s(-1) in benign acute vertebral fractures. The differences between ADC(cmb) values were statistically significant (p<0.001). The ADC is useful in differentiating benign from malignant acute vertebral body compression fractures, but there may be overlapping ADC values between malignant fractures and tuberculous spondylitis.

Discrimination of an infected brain tumor from a cerebral abscess by combined MR perfusion and diffusion imaging.

The aim of this study was to investigate the signal characteristics of the abscess wall and tumor wall on diffusion-weighted and perfusion-weighted images and thus to evaluate the feasibility of using combined MR diffusion and perfusion imaging to differentiate pyogenic cerebral abscess from infected brain tumor. The tumor wall of various types of cystic or necrotic brain tumor was significantly hyperintense relative to that of cerebral abscess wall on both diffusion-weighted images and regional cerebral blood volume maps. Sixteen patients who had cerebral masses with large cystic or necrotic cavities were imaged to generate diffusion-weighted images and regional cerebral blood volume maps using single-shot echoplanar imaging (EPI) pulse sequences. Apart from qualitative analysis, apparent diffusion coefficients (ADC) as well as regional cerebral blood volume (rCBV) ratios were calculated from the abscess wall and peripheral tumor wall and comparison was made by using Student's t-test. The tumor wall of various types of cystic or necrotic brain tumor had significantly lower ADCs relative to those of the abscess wall (P<0.005) and thus appeared relatively hyperintense on diffusion-weighted images. The mean rCBV ratio relative to normal white matter (2.90+/-0.62) of the peripheral tumor wall of various types of cystic or necrotic brain tumor were significantly larger than the mean rCBV ratio (0.45+/-0.11) of the pyogenic cerebral abscess wall (P<0.001) by Student's t-test. It is concluded that the combined MR diffusion and perfusion imaging might be capable of differentiating an infected brain tumor from a pyogenic cerebral abscess.

Reduction of radiation dose to patients undergoing barium enema by dose audit.

Nowadays, new fluoroscopic machines are usually equipped with a dose-area product (DAP) meter for dose measurement. In our hospital, DAP meters have been used in the Diagnostic Radiology Department for dose audit since June 1997. Demographic patient data, name of radiologist, fluoroscopic duration and DAP readings of every case were recorded by radiographers. In early 1999, questionnaires were distributed to radiologists who had performed fluoroscopic examinations during the auditing period. 23 radiologists with varying years of experience completed the questionnaire and their practice was analysed. Since familiarization with the examination technique would affect radiologists' practice, these radiologists were divided into two groups for analysis. Radiologists with less than 3 years of experience were grouped together as junior radiologists, whilst others were grouped as senior radiologists. Results of the questionnaire indicated that radiologists generally found DAP meters useful for dose evaluation in the process of technique refinement. Radiologists aware of being under continuous surveillance of their practice showed significant reduction of doses (junior radiologists 25%, p<0.005; senior radiologists 36%, p<0.05) and fluoroscopic times (junior radiologists 36%, p<0.001; senior radiologists 18%, p<0.05) compared with radiologists who were unaware that they were under surveillance but with similar radiological experience. This effect is believed to be because of increased awareness of radiation dose through audit. In addition, this "audit effect" may also affect junior radiologists in decision-making regarding the number of radiographs (p<0.05), but no effect was found for senior radiologists (p>0.5).

Late temporal lobe necrosis in patients with nasopharyngeal carcinoma: evaluation with combined multi-section diffusion weighted and perfusion weighted MR imaging.

Late temporal lobe necrosis is a well-known and serious complication in patients with nasopharyngeal carcinoma (NPC) following radiotherapy. Owing to the close proximity to the skull base, the medial temporal lobes are inevitably included in the target volume of irradiation. Patients with NPC provide a unique opportunity in study of delay radiation effect in normal human brain. The objective of this study was to evaluate late temporal lobe radiation injury by combined multi-section diffusion weighted and perfusion weighted MR imaging. We prospectively studied 16 patients with typical clinical symptoms of late temporal lobe necrosis or other abnormalities in the temporal lobes incidentally detected by conventional MR imaging. All patients had a previous history of radiotherapy for histologically proven NPC. Conventional T1- and T2-weighted images, fast gradient echo with echo-planar diffusion-weighted and perfusion-weighted MR imaging were performed. Apparent diffusion coefficient (ADC) map and relative cerebral blood volume (rCBV) map were computed via commercially available software. MR diffusion and perfusion images were then analyzed and graded by two independent observers with focusing on the diffusion and perfusion mismatch. The temporal lobe lesions displayed marked high diffusion on the ADC map. The rCBV map also revealed marked hypoperfusion in these temporal lobe lesions in all patients. The areas of abnormality on the rCBV map were significantly larger than the lesions on the ADC map in 14 patients (observer 1) and 13 patients (observer 2). Since late temporal lobe necrosis is probably caused by damage of the endothelium of vessels and ischemia, perfusion and diffusion mismatch might imply injured tissue but potentially salvageable brain tissue. A mismatch may be potentially used to predict the response to treatment in-patients with late temporal lobe necrosis.

Imaging features of pancreatoblastoma.

BACKGROUND: Pancreatoblastoma is a rare tumour of childhood. Reports of the imaging appearances are limited. OBJECTIVE: To define the imaging features of pancreatoblastoma by analysis of four previously unreported cases and review of the literature. MATERIALS AND METHODS: Findings at CT (n = 4), US (n = 3) and MRI (n = 2) were retrospectively reviewed in four patients with pancreatoblastoma. A Medline search was performed to identify relevant literature. RESULTS: Pancreatoblastoma arises most frequently in the body and/or tail, or involves the entire pancreas. Ultrasonography, CT and MRI show variable imaging features, but should in most cases permit preoperative distinction of pancreatoblastoma from other tumours that occur in this region in infancy and childhood. Detection of metastases in the liver, lymph nodes and peritoneal cavity is not significantly better with any one of these three modalities. CONCLUSION: Preoperative imaging with US, CT and/or MRI will usually suggest a correct diagnosis of pancreatoblastoma. Contrary to previous reports, the tumour arises in the pancreatic head in a minority of cases.

MR diffusion-weighted imaging of kidney: differentiation between hydronephrosis and pyonephrosis.

The objective of the study was to evaluate the capability and reliability of the magnetic resonance (MR) diffusion-weighted imaging (DWI) in differentiation between hydronephrosis and pyonephrosis. Single-shot echoplanar MR diffusion-weighted imaging was performed in 12 patients who had dilatation of the renal pelvis and calyces detected by ultrasonography (US). Microbiological tests confirmed that there were four cases of pyonephrosis and eight cases of hydronephrosis. Signal intensities of the collecting (pelvicalyceal) systems on the diffusion-weighted images and apparent diffusion coefficient (ADC) maps were noted. ADC values of the pelvicalyceal system in all patients were computed and compared using Student's t test. On diffusion-weighted images, the pelvicalyceal system of the hydronephrotic kidney was hypointense while the pelvicalyceal system of the pyonephrotic kidney was markedly hyperintense. The mean ADCs of the hydronephrotic and pyonephrotic renal pelvis were 2.98 +/- 0.65 x 10(-3) and 0.64 +/- 0.35 x 10(-3) mm(2)/s, respectively. The extremely low ADC of the renal pelvis of the pyonephrotic kidney accounted for its signal hyperintensity on diffusion-weighted images as well as signal hypointensity on ADC maps. In conclusion, the MR diffusion-weighted imaging may be a reliable tool to differentiate pyonephrosis from hydronephrosis.

Spontaneous intracranial hypotension with diffuse dural enhancement of the spinal canal and transient enlargement of the pituitary gland.

Spontaneous intracranial hypotension is a rare phenomenon characterized by postural headache, neck rigidity, nausea and vomiting. Imaging findings on magnetic resonance imaging (MRI) is characteristic with diffuse intracranial pachymeningeal thickening and enhancement following intravenous gadolinium. We present a case of spontaneous intracranial hypotension with two unusual imaging findings; pachymeningeal enhancement of the spinal canal and enlargement of the pituitary gland in addition to the diffuse intracranial pachymeningeal enhancement. In this case report, we will discuss the clinical features, MRI findings and underlying pathophysiology of this rare condition.

Primary multifocal leptomeningeal gliomatosis.

A 23-year-old female university student was presented with recent onset of non-specific headache and dizziness. She had no neurological deficit on neurological examination and magnetic resonance imaging of the brain revealed diffuse enhancement in the basal cisterns and cerebral sulci. She was treated as tuberculous meningitis but she did not improve and developed respiratory arrest. Autopsy showed primary multifocal leptomeningeal gliomatosis.