Normative reference data for intracranial volume in children: The results of CT volumetry

BACKGROUND

Intracranial volume (ICV) is an important indicator of the development of the brain and skull in children. At present, there is a lack of ICV growth standards based on large infant and children samples. Our aim was to assess the normal range of the ICV variation in Russian children using a modern automatic system for constructing the endocranial cavity (Endex) and to provide growth standards of the ICV for clinical practice.

METHODS

High-resolution head CT scans were obtained from 673 apparently healthy children (380 boys and 293 girls) aged 0-17 years and transformed into the ICV estimates using the Endex software. The open-source software RefCurv utilizing R and the GAMLSS add-on package with the LMS method was then used for the construction of smooth centile growth references for ICV according to age and sex.

RESULTS

We demonstrated that the ICVs estimates calculated using the Endex software are perfectly comparable with those obtained by a conventional technique (i.e. seed feeling). Sex-specific pediatric growth charts for ICV were constructed.

CONCLUSIONS

This study makes available for use in clinical practice ICV growth charts for the age from 0 to 17 based on a sample of 673 high-resolution CT images.

Multivariate Analysis of Vocal Fold Vibrations in Normal Speakers Using High-Speed Digital Imaging

INTRODUCTION

Little is known about the normal variations in vocal fold vibrations. We conducted a prospective study on normal subjects using high-speed digital imaging (HSDI) to elucidate key parameters regarding age/gender-related normal variations.

METHODS

Forty-six healthy adult volunteers were divided into young (aged ≤35 years) male, young female, elderly (aged ≥65 years) male, and elderly female subgroups. HSDI data of sustained phonation of /i/ at a comfortable pitch and loudness were obtained, and vibratory parameters were calculated using the visual-perceptual rating, laryngotopography, digital kymography, and glottal area waveform. Multivariate analysis was then performed on these parameters to clarify the subgroup-specific key parameters.

RESULTS

Four key parameters were identified from a total of 83: one from visual perceptual rating and three from laryngotopography. Subgroup analyses showed that posterior-to-anterior longitudinal phase difference (PD) and high fundamental frequency (F0) were specific to young female participants. A low F0 was specific to young male participants. Large anterior-to-posterior longitudinal PD and its left-right difference were specific to elderly male participants. There were no key parameters for elderly female participants.

CONCLUSIONS

Methods that can assess F0 and longitudinal PD, such as visual-perceptual rating and laryngotopography, were effective in the evaluation of normal vocal fold vibrations and their variations.

Multiple portal veins in the hepatoduodenal ligament: Evidence of "duodenal reverse rotation" hypothesis?

Duplication of the portal vein is a rare variation, and reports of this condition are quite limited. The present report describes a woman of advanced age who was incidentally diagnosed with duplicated portal veins. The portal vein from the splenic vein distributed to the left lobe of the liver, and that from the superior mesenteric vein ran between the pancreas and duodenum to distribute to the right lobe. The former portal vein connected with the round ligament, and its presumptive origin was the left vitelline vein. The latter was presumably from the right vitelline vein. Between the 2 portal veins, 2 anastomotic veins were identified; one anastomosis was posterior to the pancreatic head, and the other was intrahepatic. The common bile duct was located posterolateral to the portal veins. The relationships of these veins to the round ligament and common bile duct support the reverse rotation hypothesis of the duodenum in the development of portal vein variations.

Normal variations of the superior vena cava and azygos venous system depiction by CT scan in the adult Thai population

BACKGROUND

Identification of normal variations to the thoracic central venous system anatomy is essential in radiological intervention and cardiothoracic surgery to prevent complications.

PURPOSE

To estimate the prevalence and pattern of normal variations of superior vena cava (SVC) and azygos venous system as well as factors associated with normal variations of SVC.

MATERIAL AND METHODS

Venous-phase chest CT of 1336 patients were retrospectively reviewed. Age, sex, and underlying disease were recorded. SVC diameter and cross-sectional area were measured to evaluate for associations with normal variations.

RESULTS

The prevalence of normal anatomical variations of SVC and azygos venous system were 0.3% and 1.5%, respectively. Duplicated SVC was the most common variations. The most common variation for the azygos venous system was the connection between the hemiazygos and accessory hemiazygos veins draining into the left brachiocephalic vein (12/1336 cases, 0.9%). The median (interquartile range [IQR]) cross-sectional area compared between normal SVC (297.2 mm2) and duplicated SVC (223.5 mm2) showed a statistically significant difference (P = 0.033).

CONCLUSION

This study determined the prevalence of rare normal variations of the azygos venous system, a connection between the hemiazygos and accessory hemiazygos veins draining into the left brachiocephalic vein. The prevalence of normal variations of the SVC and azygos venous system in the adult Thai population was similar with that of previous publications. Cross-sectional area was the only factor with a significant association with SVC variations.

Multivariate Analysis of Vocal Fold Vibrations in Normal Speakers Using High-Speed Digital Imaging

INTRODUCTION

Little is known about the normal variations in vocal fold vibrations. We conducted a prospective study on normal subjects using high-speed digital imaging (HSDI) to elucidate key parameters regarding age/gender-related normal variations.

METHODS

Forty-six healthy adult volunteers were divided into young (aged ≤35 years) male, young female, elderly (aged ≥65 years) male, and elderly female subgroups. HSDI data of sustained phonation of /i/ at a comfortable pitch and loudness were obtained, and vibratory parameters were calculated using the visual-perceptual rating, laryngotopography, digital kymography, and glottal area waveform. Multivariate analysis was then performed on these parameters to clarify the subgroup-specific key parameters.

RESULTS

Four key parameters were identified from a total of 83: one from visual perceptual rating and three from laryngotopography. Subgroup analyses showed that posterior-to-anterior longitudinal phase difference (PD) and high fundamental frequency (F₀) were specific to young female participants. A low F₀ was specific to young male participants. Large anterior-to-posterior longitudinal PD and its left-right difference were specific to elderly male participants. There were no key parameters for elderly female participants.

CONCLUSIONS

Methods that can assess F₀ and longitudinal PD, such as visual-perceptual rating and laryngotopography, were effective in the evaluation of normal vocal fold vibrations and their variations.

Prevalence of metaphyseal injury and its mimickers in otherwise healthy children under two years of age

BACKGROUND

Metaphyseal lesions in infants and toddlers are believed to have a high specificity for inflicted injury.

OBJECTIVES

To examine the prevalence of metaphyseal injury and its mimickers in otherwise healthy children younger than 2 years of age.

MATERIALS AND METHODS

During 2010-2015, all children 2 years old and younger seen at the Accident and Emergency (A&E) Department due to an injury who had radiographs taken were included. Information on mechanism and clinical findings were drawn from the medical notes. All radiographs were reviewed by two of five researchers together with an experienced paediatric radiologist, registering fracture site and type, and metaphyseal appearances.

RESULTS

Four hundred and eight children (212 boys) (mean age: 17.7 months, range: 3-24 months) were included, of whom 149 (77 boys) had a total of 162 fractures (incidence of 5.4 per 1,000 children). Only one metaphyseal lesion, without a history of trauma, was seen. Of the 860 metaphyses analysed, 140 (16.3%) were defined as either irregular (74/860, 8.6%) or as having a metaphyseal collar (66/860, 7.7%). Sixty-four of the 66 collars (97.0%) and 54/104 irregularities (60.8%) were located around the wrist and the ankle, while 25/74 irregularities (33.8%) were found around the knee joint.

CONCLUSION

Metaphyseal lesions with a history of trauma did not occur in otherwise healthy neonates and infants younger than 2 years of age, indicating that this type of fracture has a particular trauma mechanism. Metaphyseal irregularities/collars are frequently seen and should not be mistaken for a classic metaphyseal lesion.

Lacrimal gland uptake on F-18 florbetapir amyloid positron emission tomography scan

In 2012, the Food and Drug Administration (FDA) approved the use of F-18 florbetapir to estimate β-amyloid neuritic plaque density when indicated. A normal scan will show increased radiotracer uptake in the white matter. Mild uptake in salivary glands, skin, muscles, and bones is considered normal. Being a new and infrequently performed study, familiarity with normal biodistribution and variants is important. We hereby present 2 cases with F-18 florbetapir uptake in lacrimal glands. Patients had no symptoms or known systemic conditions to explain this uptake. We speculate that lacrimal gland uptake of F-18 florbetapir could represent a normal variant.

Cancer associated proteins in blood plasma: Determining normal variation

Protein biomarkers have the potential to improve diagnosis, stratification of patients into treatment cohorts, follow disease progression and treatment response. One distinct group of potential biomarkers comprises proteins which have been linked to cancer, known as cancer associated proteins (CAPs). We determined the normal variation of 86 CAPs in 72 individual plasma samples collected from ten individuals using SRM mass spectrometry. Samples were collected weekly during 5 weeks from ten volunteers and over one day at nine fixed time points from three volunteers. We determined the degree of the normal variation depending on interpersonal variation, variation due to time of day, and variation over weeks and observed that the variation dependent on the time of day appeared to be the most important. Subdivision of the proteins resulted in two predominant protein groups containing 21 proteins with relatively high variation in all three factors (day, week and individual), and 22 proteins with relatively low variation in all factors. We present a strategy for prioritizing biomarker candidates for future studies based on stratification over their normal variation and have made all data publicly available. Our findings can be used to improve selection of biomarker candidates in future studies and to determine which proteins are most suitable depending on study design.

Initial assessment and management of the newborn

This article summarizes the initial assessment of normal newborns and describes a few of the common variations that may occur. These variations require a pediatric provider to reassure anxious new parents and provide follow-up communication with the subsequent primary care provider.