Quantitative cerebral perfusion imaging in children and young adults with Moyamoya disease: comparison of arterial spin-labeling-MRI and H(2)[(15)O]-PET.

BACKGROUND AND PURPOSE: Cerebral perfusion assessment is important in the preoperative evaluation and postoperative follow-up of patients with Moyamoya disease. The objective of this study was to evaluate the correlation of quantitative CBF measurements performed with arterial spin-labeling-MR imaging and H2[(15)O]-PET in children and young adults with Moyamoya disease. MATERIALS AND METHODS: Thirteen children and young adults (8 female patients; age, 9.7 ± 7.1 years; range, 1-23 years) with Moyamoya disease underwent cerebral perfusion imaging with H2[(15)O]-PET (Discovery STE PET/CT, 3D Fourier rebinning filtered back-projection, 128 × 128 × 47 matrix, 2.34 × 2.34 × 3.27 mm(3) voxel spacing) and arterial spin-labeling (3T scanner, 3D pulsed continuous arterial spin-labeling sequence, 32 axial sections, TR = 5.5 seconds, TE = 25 ms, FOV = 24 cm, 128 × 128 matrix, 1.875 × 1.875 × 5 mm(3) voxel spacing) within less than 2 weeks of each other. Perfusion of left and right anterior cerebral artery, MCA, and posterior cerebral artery territories was qualitatively assessed for arterial spin-labeling-MR imaging and H2[(15)O]-PET by 2 independent readers by use of a 3-point-Likert scale. Quantitative correlation of relative CBF with cerebellar normalization between arterial spin-labeling-MR imaging and H2[(15)O]-PET was evaluated in a volume-based approach for each vascular territory after 3D image coregistration. RESULTS: Interreader agreement was good (κ = 0.67-0.69), and strong and significant correlations were found between arterial spin-labeling-MR imaging and H2[(15)O]-PET for both qualitative perfusion scoring (ρ = 0.77; P < .001) and quantitative perfusion assessment of relative CBF with cerebellar normalization (r = 0.67, P < .001). CONCLUSIONS: In children and young adults with Moyamoya disease, quantitative evaluation of CBF is possible with the use of arterial spin-labeling-MR imaging without ionizing radiation or contrast injection with a good correlation to H2[(15)O]-PET after cerebellar normalization.

[Balloon dacryocystoplasty: interventional radiological therapy of congenital dacryostenosis]. / Ballondakryozystoplastie: Interventionell-radiologische Therapie konnataler Dakryostenosen.

PURPOSE: To evaluate the results of balloon dacryocystoplasty in the treatment of complicated development of connatal obstructed nasolacrimal duct system. MATERIALS AND METHODS: Dacryocystography under general anaesthesia was performed on 46 children with epiphora from birth and recurrent infection of the nasolacrimal duct system. 54 nasolacrimal ducts (8 children bilaterally) were treated with balloon catheter dilatation and antibiotic irrigation of the nasolacrimal sac. In all cases previous conservative treatment with eye drops and superficial massage of the lacrimal sac had failed. 11 children without clinical improvement were irrigated before catheter dilatation by an ophthalmologist. The ages ranged from 6 weeks to 7.5 years (mean 23.5 months). 39 dilatations were carried out as an out-patient procedure. The clinical results were confirmed by a questionnaire filled in by the parents. RESULTS: 15 incomplete obstructions and 39 occlusions of the Hasner valve (n = 45) or of the nasolacrimal duct system (n = 9) were demonstrated with dacryocystography. Dilatation with a 2.5 mm ballon was successfully performed in all cases and the mean radiation time was 2.1 minutes. No relevant complications occurred. The mean follow up time was 18.4 months (3 - 41 months). 39 of 46 children showed no symptoms, 6 children seldomly experienced onset of epiphora. The symptoms did not improve in only one child. The cumulative clinical success rate is 98 %. CONCLUSION: Following diagnostic dacryocystography, balloon catheter dilatation is a low risk and very successful treatment of complicated connatal obstructed nasolacrimal duct system.

[Circumscribed median nerve compression caused by a leiomyoma. Preoperative localization with spiral CT]. / Punktuelle Läsion des Nervus medianus bei Einschnürung durch ein Leiomyom. Präoperative Lokalisation mittels Spiral-CT.

Dysfunction of the median nerve is quite common and mostly observed related to carpal tunnel and pronator syndromes. We report a rare case of median nerve compression caused by a leiomyoma in the distal forearm. Spiral CT with MPR (multiplanar reconstruction) clearly located the lesion preoperatively.

Computed tomographic angiography findings in 103 patients following vascular events in the posterior circulation: potential and clinical relevance.

We studied the diagnostic value of computed tomographic angiography (CTA) in the posterior circulation as a noninvasive substitute for intra-arterial digital subtraction angiography (DSA). We prospectively investigated 103 patients with acute stroke in the posterior circulation. All patients underwent CTA and Doppler ultrasound, and DSA was performed in 22 patients. Vascular findings were classified in categories according to the type of lesion and the location in the vertebral, basilar, or posterior cerebral artery. In the first part of the analysis we examined the correlation between CTA and intra-arterial DSA (n=22), and in the second part that between CTA and Doppler ultrasound (n=103). Intra-arterial DSA identified 11 stenoses, 13 occlusions, and 3 hypoplasias. The correlation between DSA and CTA was best for the basilar artery (all lesions were identified with CTA). Of the 14 lesions detected in the vertebral artery by DSA 13 were also detected by CTA, but the specific type of lesion was identified in only 7 cases. The correlation between CTA and Doppler ultrasound was lower. In conclusion, CTA is thus a reliable method for detecting lesions in the posterior circulation and may replace DSA in many cases. However, particularly in the vertebral artery DSA remains the superior technique.

The epidemiology of serious eye injuries from the United States Eye Injury Registry.

BACKGROUND: Trauma remains a major problem throughout the world. The prognosis of severe eye injuries is commonly bleak. This paper focuses on the epidemiology of eye trauma, the role of ocular epidemiology, and identification and reduction of risk factors. METHODS: An analysis of the first 8,952 patients reported with severe eye injuries, defined as those eye injuries resulting in permanent and significant (measurable and observable on routine eye examination) structural and/or functional changes to the eye, from the United States Eye Injury Registry as of 31 July 1998. RESULTS: The age of patients entered was from the 1st year of life to 103 years. Fifty-eight percent of those injured were less than 30 years of age. The male to female ratio was 4.6:1, reaching 7.4:1 in the fourth decade of life. Almost half of the injuries involved the retina, and 77% of the injured eyes required one or more surgical procedures, including a large proportion which have undergone vitreoretinal surgical procedures. CONCLUSION: Injuries remain the most serious public health problem facing developed nations. Yet, a persistent inadequacy exists both in the standardized documentation of eye injuries and in their treatment. With appropriate surgical and medical intervention, a majority of the reported injured eyes recovered functional levels of visual acuity. It appears that glasses, including prescription glasses and even non-prescription sunglasses, can offer measurable protection which results in a lower incidence of severe eye injuries to those wearing glasses.

Intracranial stenoocclusive disease: double-detector helical CT angiography versus digital subtraction angiography.

BACKGROUND AND PURPOSE: To our knowledge, no large-scale studies comparing the accuracy of CT angiography (CTA) to intraarterial digital subtraction angiography (DSA) of intracranial stenosis have been reported. We attempted to determine the diagnostic value of intracranial CT angiography (CTA) of normal vasculature and variants as well as of stenoocclusive disease. METHODS: One-hundred and twelve patients underwent CTA and intraarterial angiography, and 2205 vascular segments were examined to ascertain presence, visibility, and degree of arterial stenoses (n = 105) as well as anatomic variants. Source, maximum intensity projection (MIP), and MIP-generated multiplanar reformatted (MPR) images were evaluated. RESULTS: All 55 anatomic variants were identified correctly. Visibility of small-vessel segments was increased from 75% to 83% by using source images. MPR was helpful in differentiating distal vertebral hypoplasia from stenosis and in overcoming artifacts. All 43 occlusive segments were graded correctly (sensitivity = 100%, predictive value = 93.4%) as follows: severely stenotic ([n = 23], sensitivity = 78%, predictive value = 81.8%); moderately stenotic ([n = 36], sensitivity = 61%, predictive value = 84.6%); and mildly stenotic ([n = 3], sensitivity = 66%, predictive value = 28%). Normal segments (n = 2100) had a sensitivity of 99.5%, and CTA evinced a specificity of 99% for detecting stenoocclusive disease. Approximately one-third of wrong assessments were related to the petrous segment of the carotid artery. CONCLUSION: CTA with double-detector technology and advanced postprocessing algorithms, including MPR, is about as reliable as MRA in depicting the vasculature of the anterior and posterior circulation and in grading intracranial stenoocclusive lesions, with the exception of the petrous segment of the carotid artery. CTA might be superior to MRA in the evaluation of poststenotic low-flow segments.

[3-phase spiral CT of the liver, Value of non-contrast arterial and portal venous studies in the diagnosis of focal liver lesions]. / 3-Phasen-Spiral-CT der Leber. Stellenwert von nativer, arterieller und portalvenöser Untersuchungsserie für die Diagnostik fokaler Leberläsionen.

PURPOSE: To assess the value of noncontrast, arterial and portal venous phase of triphasic helical CT in detecting and characterising focal liver lesions. MATERIAL AND METHODS: 120 patients with focal liver disease underwent triphasic helical CT examinations with a collimation of 6.5 mm at a table feed of 6.5 mm/s. The liver scans were obtained before the administration of 120 ml of non-ionic contrast material (flow 2 or 3 ml/s), at the arterial phase, and at the portal venous phase (20 s, respectively 60 s after injection). Patients were divided into four groups according to the underlying disease and enhancement pattern. The studies were evaluated retrospectively. RESULTS: A total of 269 lesions was seen. The noncontrast phase (NCP) revealed 86% of lesions, the arterial phase (AP) 95% and the portal venous phase (PVP) 91%. In the first group of hypovascular lesions (colorectal carcinoma) all lesions (73/73) were detected in the PVP. In the second group of hypervascular lesions (breast cancer, melanoma) the combination of AP and PVP revealed 73 of 74 lesions. In the third group of patients with unknown primary and detected lesions by sonography all 89 lesions were detected with the combination of AP and PVP. In the fourth group of patients with cirrhosis 3 of 33 lesions were detected exclusively during the AP and 3 other lesions exclusively during the NCP. To make a definitive diagnosis of focal liver lesions the value of the three phases was as follows: to characterise lesions the PVP was sufficient in 62%, the combination of PVP and AP in 27%, and the combination of all three phases in 11%. CONCLUSIONS: If hypovascular lesions are suspected examination during PVP is sufficient. In cases of hypervascular lesions and lesions of unknown primary AP and PVP should be combined. Unenhanced scans are of additional diagnostic value only in patients with liver cirrhosis.

[CT angiography of cerebral venous circulation: anatomical visualization and diagnostic pitfalls in interpretation]. / CT-Angiographie des venösen Zerebralkreislaufes: anatomische Darstellbarkeit und Fehlerquellen in der Beurteilung.

PURPOSE: To show the frequency of visualisation of the dural sinuses and cerebral veins with CT-angiography (CTA) with special reference to anatomical variants. METHODS: 34 CTA (1 mm slice thickness, 120 ml nonionic KM, 2 ml/s flow, 40 s prescanning delay) were performed in 30 patients to examine the cerebral venous system. In an anatomic study of cadavers (n = 10) without known disease of the cerebral veins the great sinuses were opened and examined. RESULTS: The superior sagittal, the transverse, the sigmoid and the straight sinus could be evaluated in all cases (100%). The cortical and deep cerebral veins as well as the small sinuses were visualised in 12-97% of the examinations. A sinovenous thrombosis was diagnosed in 4 of the 30 patients. Asymmetric superior sagittal sinus bifurcation (12/30), a hypoplastic sinus transversus (2/30) and a persistent sinus occipitalis (4/30) were found as anatomical variants. In 10 of the 30 patients we discovered 17 dural sinus filling defects produced by large arachnoid granulations. Similar findings could be demonstrated in the pathologico-anatomic examination series. CONCLUSION: CT angiography is suitable for detailed evaluation of the cerebral veins. Anatomic variants, arachnoid granulations, as well as fibrous bands and septa, which may lead to misinterpretation in conventional CT, can be clearly demonstrated. The sensitivity and specificity of CT in diagnosis of sinovenous thrombosis were increased thereby.