Cranial CT with 64-, 16-, 4- and single-slice CT systems–comparison of image quality and posterior fossa artifacts in routine brain imaging with standard protocols

Posterior fossa artifacts constitute a characteristic limitation of cranial CT. To identify practical benefits and drawbacks of newer CT systems with reduced collimation in routine cranial imaging, we aimed to investigate image quality, posterior fossa artifacts and parenchymal delineation in non-enhanced CT (NECT) with 1-, 4-, 16- and 64-slice scanners using standard scan protocols. We prospectively enrolled 25 consecutive patients undergoing NECT on a 64-slice CT. Three groups with 25 patients having undergone NECT on 1-, 4- and 16-slice CT machines were matched regarding age and sex. Standard routine CT parameters were used on each CT system with helical acquisition in the posterior fossa; the parameters varied regarding collimation and radiation dose. Three blinded readers independently assessed the cases regarding image quality, infra- and supratentorial artifacts and delineation of brain parenchymal structures on a five-point ordinal scale. Reading orders were randomized. A proportional odds model that accounted for the correlated nature of the data was fit using generalized estimating equations. Posterior fossa artifacts were significantly reduced, and the delineation of infratentorial brain structures was significantly improved with the thinner collimation used for the newer CT systems (p<0.001). No significant differences were observed for midbrain structures (p>0.5). The thinner collimation available on modern CT systems leads to reduced posterior fossa artifacts and to a better delineation of brain parenchyma in the posterior fossa.     

Exercise,Intestinal Absorption,and Rehydration

ＫＥＹＰＯＩＮＴＳ1.Ｔｈｅｐｒｏｘｉｍａｌｓｍａｌｌｉｎｔｅｓｔｉｎｅ(ｄｕｏｄｅｎｕｍ＆ｊｅｊｕｎｕｍ)ｉｓｔｈｅｐｒｉｍａｒｙｓｉｔｅｏｆｆｌｕｉｄａｂｓｏｒｐｔｉｏｎ .Ｉｔａｂｓｏｒｂｓａｂｏｕｔ 50 %ｔｏ 60 %ｏｆａｎｙｇｉｖｅｎｆｌｕｉｄｌｏａｄ .Ｔｈｅｃｏｌｏｎｏｒｌａｒｇｅｉｎｔｅｓ ｔｉｎｅａｂｓｏｒｂｓａｐｐｒｏｘｉｍａｔｅｌｙ 80ｔｏ 90 %ｏｆｔｈｅｆｌｕｉｄｉｔｒｅ ｃｅｉｖｅｓ ,ｂｕｔａｃｃｏｕｎｔｓｆｏｒｏｎｌｙａｂｏｕｔ 15%ｏｆｔｈｅｔｏｔａｌｆｌｕｉｄｌｏａｄ .2 .Ｉｎｔｅ…     

Gorham-Stout disease and generalized lymphatic anomaly—clinical, radiologic, and histologic differentiation

Purpose

Gorham-Stout disease (GSD) is a rare vascular disorder of lymphatic origin characterized by progressive osteolysis. Generalized lymphatic anomaly (GLA) is a multisystem disorder that also commonly affects bone. We hypothesized that Gorham-Stout disease is different from other osseous lymphatic anomalies. We proposed to discriminate these entities by analyzing findings on skeletal imaging.

Methods

Clinical data, imaging studies, and histopathologic findings were retrospectively reviewed in patients presenting to our Vascular Anomalies Center with lymphatic anomalies of bone.

Findings

Within a cohort of 51 patients with lymphatic disorder and radiological evidence of bony involvement, two distinct categories emerged. Nineteen patients met the imaging criteria for GSD: progressive osteolysis with resorption and cortical loss. Thirty-two were categorized as GLA: Discrete radiolucencies and increasing numbers of bone affected over time, but without evidence of progressive osteolysis. The ribs were the most common site in both groups, followed by the cranium, clavicle, and cervical spine in GSD, and thoracic spine, humerus, and femur in GLA. Fewer bones were involved in GSD, with relative sparing of the appendicular skeleton. Associated infiltrative soft tissue abnormality was seen in 18 in GSD, but only six with GLA. Macrocystic lymphatic malformations were identified in 14 with GLA, but none with GSD.

Conclusions

There are significant radiological differences between GSD and GLA, although there are some overlapping features. The major distinguishing characteristic is the progressive osteolysis seen in GSD. Findings suggestive of GLA are more extensive involvement, particularly of the appendicular skeleton, presence of discretemacrocystic lymphatic malformations and visceral organ lesions.     

Diabetes, Exercise and Competitive Sports

KEYPOINTS Peoplewithdiabetesmellitus—rapidlyapproachingone-thirdoftheUSpopulation—eithercannotproduce insulin(Type1DM)ortheinsulintheyproduceisin effectiveinstimulatingtheuptakeofbloodsugar(glu cose)intothebody’scells(Type2DM).According ly,ifdiabetesisuntreated,bloodsugarrisestodan gerouslyhighlevelsthatcaneventuallycauseblind ness,nervedamage,andothercomplications.Bloodsugarcanbecontrolledbytheappropriatead ministrationofinsulinandotherdrugsand/orbythe manipulationofdietarycarbohydra…     

Naming, blaming and shaming?

Few doctors at the centre of complaints or disciplinary proceedings wish to be publicly named. Publication of a doctor's name can adversely affect his or her reputation, patients, and family members, even if the allegation is ultimately not upheld. Yet, there is a strong public interest in freedom of speech and transparency of complaints and disciplinary processes. In determining whether to grant name suppression, complaints agencies and disciplinary tribunals are required to balance competing public and private interests. In New Zealand, the Health and Disability Commissioner has responsibility for investigating complaints about the quality of medical care. The Commissioner's current practice is not to publicly name doctors under investigation, or even those who are found to have breached a patient's rights. This approach fits well the non-punitive, rehabilitative focus of New Zealand's medical regulatory system. In the rare cases where a matter reaches the threshold for disciplinary action, the balance tips in favour of disclosure.     

Ultra-triathlon—Pacing,performance trends,the role of nationality,and sex differences in finishers and non-finishers

Ultra-triathlons are defined as triathlons longer than the traditional Ironman distance and became more popular in the last two decades; however, scarce scientific evidence of these events are available. Therefore, we aimed to investigate the trends of performance, pacing, nationality, sex differences, and rate of non-finishers in ultra-triathlons. Data from 1985 to 2018 were collected including Double Iron, Triple Iron, Quintuple Iron, and Deca Iron ultra-triathlons. Different pacing patterns by event and sex were observed (P < .05); athletes spent less %time in swimming and cycling, and more %time in running as the distance of event was longer; women spent more %time in cycling and less% time in running in Double and Triple. Performance analysis showed a negative trend over time for men and women since 1985. Switzerland, France, and Germany were the fastest nations in ultra-triathlons. The frequency of North Americans competing in Europe was very low (<5%), whereas Europeans often competed in North America (~25%). The rate of non-finishers between sexes was similar in all races with the exception of Deca Iron ultra-triathlon, which was much greater (~20%) for women. Non-finishers had slower race times in swimming and cycling splits than finishers. In conclusion, ultra-triathletes should redistribute their energy among swimming, cycling, and running depending on their sex and distance of race. Performance in ultra-triathlons has been decreasing in men and women over the years, but sex difference in performance remained. Europeans were the fastest ultra-triathletes and compete in Europe and North America. Additionally, non-finishers were slower swimmers and cyclists than finishers.     

Fibrous dysplasia and McCune–Albright syndrome: Imaging for positive and differential diagnoses,prognosis, and follow-up guidelines

Purpose

The radiologist plays a critical role at all steps of the management of patients with fibrous dysplasia (FD) and McCune–Albright syndrome (MAS). The development of a standardized approach to the management of FD/MAS is crucial given the low incidence and multiple clinical presentations of these conditions. Our aim was to develop recommendations for bone imaging in FD/MAS management.

Materials and methods

The establishment of National Reference Centers in France as part of a Health Ministry program for orphan diseases has triggered the development of recommendations for the clinical management of FD/MAS. We used a well-established robust methodological approach involving an extensive literature review by a multidisciplinary working group (20 healthcare professionals) and scoring by a peer-review group (20 healthcare professionals different from the 20 previous ones). There were four phases: a systematic literature review, drafting of initial recommendations, peer-review of this initial draft, and drafting of the final recommendations.

Results

Fifty-seven specific recommendations are provided as key points for the diagnosis, prognosis, and follow-up of patients with FD/MAS. Issues of special interest are highlighted in the discussion, and areas in which future research is needed are identified.

Conclusion

We believe the dissemination of these recommendations within the radiology community may facilitate communication between radiologists and other healthcare providers, thereby substantially improving the management of patients with these rare but potentially disabling conditions.