Natural Language Processing Algorithm Used for Staging Pulmonary Oncology from Free-Text Radiological Reports: "Including PET-CT and Validation Towards Clinical Use"

Natural language processing (NLP) can be used to process and structure free text, such as (free text) radiological reports. In radiology, it is important that reports are complete and accurate for clinical staging of, for instance, pulmonary oncology. A computed tomography (CT) or positron emission tomography (PET)-CT scan is of great importance in tumor staging, and NLP may be of additional value to the radiological report when used in the staging process as it may be able to extract the T and N stage of the 8th tumor-node-metastasis (TNM) classification system. The purpose of this study is to evaluate a new TN algorithm (TN-PET-CT) by adding a layer of metabolic activity to an already existing rule-based NLP algorithm (TN-CT). This new TN-PET-CT algorithm is capable of staging chest CT examinations as well as PET-CT scans. The study design made it possible to perform a subgroup analysis to test the external validation of the prior TN-CT algorithm. For information extraction and matching, pyContextNLP, SpaCy, and regular expressions were used. Overall TN accuracy score of the TN-PET-CT algorithm was 0.73 and 0.62 in the training and validation set (N = 63, N = 100). The external validation of the TN-CT classifier (N = 65) was 0.72. Overall, it is possible to adjust the TN-CT algorithm into a TN-PET-CT algorithm. However, outcomes highly depend on the accuracy of the report, the used vocabulary, and its context to express, for example, uncertainty. This is true for both the adjusted PET-CT algorithm and for the CT algorithm when applied in another hospital.

Post-mortem radiology in fetal and neonatal death: the diagnostic value of post-mortem MRI versus autopsy regarding non-cardiac thoracic and abdominal abnormalities

AIM

To compare the diagnostic value and accuracy of post-mortem magnetic resonance imaging (PMMRI) and autopsy for non-cardiac thoracic and abdominal abnormalities in fetal death.

MATERIALS AND METHODS

This single-institution retrospective study included all consecutive cases of fetal and perinatal death between January 2015 and December 2021 for which PMMRI followed by autopsy was conducted. These cases comprised fetuses at >18 weeks of gestation and preterm and term neonates who lived for <24 h. All PMMRI and autopsy reports were re-assessed and scored for seven non-cardiac thoracic and 52 abdominal abnormalities, and concordance between autopsy and PMMRI findings was determined as the primary outcome.

RESULTS

Eighty cases were included in this study. Fetal loss was caused by termination of pregnancy in 80% of cases. Further, the mean gestational age was 166 days (23 weeks and 5 days, range 126-283 days). The concordance between PMMRI and autopsy for non-cardiac thoracic and abdominal abnormalities was 83.1% (95% confidence interval [CI] 71.3-83.3) and 76.3% (95% CI 65.8-84.2%), respectively, with a substantial and moderate strength of agreement (Cohen's kappa = 0.63 and 0.51 respectively).

CONCLUSION

PMMRI exhibited good overall diagnostic value for non-cardiac thoracic and abdominal abnormalities, specifically large structural abnormalities. PMMRI may offer parents and physicians a valuable addition to autopsy for the detection of non-cardiac thoracic and abdominal abnormalities, or even an alternative option when parents do not consent to autopsy.

Active monitoring versus an abduction device for treatment of infants with centered dysplastic hips: study protocol for a randomized controlled trial (TReatment with Active Monitoring (TRAM)-Trial)

BACKGROUND

Developmental Dysplasia of the Hip (DDH) is one of the most common pediatric orthopedic disorders, affecting 1-3% of all newborns. The optimal treatment of centered DDH is currently under debate. This randomized controlled trial aims to study the (cost-)effectiveness of active monitoring versus abduction treatment for infants with centered DDH.

METHODS

This is a multicenter, parallel-group, open-label, non-inferiority randomized controlled trial studying the (cost-)effectiveness of active monitoring versus abduction treatment for infants with centered DDH in fourteen hospitals in the Netherlands. In total, 800 infants with centered DDH (Graf IIa-/IIb/IIc), aged 10-16 weeks, will be randomly allocated to the active monitoring or abduction treatment group. Infants will be followed up until the age of 24 months. The primary outcome is the rate of normal hips, defined as an acetabular index lower than 25 degrees on an antero-posterior radiograph, at the age of 12 months. Secondary outcomes are the rate of normal hips at the age of 24 months, complications, time to hip normalization, the relation between baseline patient characteristics and the rate of normal hips, compliance, costs, cost-effectiveness, budget impact, health-related quality of life (HRQoL) of the infant, HRQoL of the parents/caregivers, and parent/caregiver satisfaction with the treatment protocol.

DISCUSSION

The outcomes of this randomized controlled trial will contribute to improving current care-as-usual for infants with centered DDH.

TRIAL REGISTRATION

Dutch Trial Register, NL9714, registered September 6, 2021. https://clinicaltrialregister.nl/en/trial/29596.

Postmortem Diffusion-Weighted Magnetic Resonance Imaging of the Brain in Perinatal Death: An Animal Control Study to Detect the Influence of Postmortem Interval

OBJECTIVES

Diffusion-weighted imaging may be useful as part of a postmortem magnetic resonance imaging protocol. However, apart from the effect of temperature on apparent diffusion coefficient (ADC), normal postmortem ADC changes can influence the interpretation. Therefore, this study was conducted to evaluate the correlation between normal ADC changes and postmortem intervals (PMIs) and develop a reference standard for postmortem changes after temperature correction.

MATERIALS AND METHODS

Six premature lambs were scanned at different PMIs. ADC values were measured at different parenchymal locations. Correlation and linear regression between ADC values and PMI were analyzed for all locations, both uncorrected and corrected for temperature.

RESULTS

All locations showed a significant negative correlation between the PMI and ADC value, with (R2 = 0.581-0.837, P < 0.001) and without (R2 = 0.183-0.555, P < 0.001-0.018) temperature correction.

CONCLUSIONS

The postmortem interval is negatively correlated with ADC values in the brain. A correlation coefficient for the PMI can be calculated after temperature correction to predict ADC changes. However, further research is required to evaluate its clinical application in humans.

Treatment of decentered developmental dysplasia of the hip under the age of 1 year: an evidence-based clinical practice guideline - Part 2

Background and purpose

Materials and methods

Results

Interpretation

Treatment of centered developmental dysplasia of the hip under the age of 1 year: an evidence-based clinical practice guideline

Despite the high incidence of developmental dysplasia of the hip (DDH), treatment is very diverse. Therefore, the Dutch Orthopedic Society developed a clinical practice guideline with recommendations for optimal and uniform treatment of DDH. This article summarizes the guideline on centered DDH (i.e. Graf types 2A–C).

The guideline development followed the criteria of Appraisal of Guidelines for Research and Evaluation II. A systematic literature review was performed to identify randomized controlled trials and comparative cohort studies including children <1 year with centered DDH. Articles were included that compared (1) treatment with observation, (2) different abduction devices, (3) follow-up frequencies, and (4) discontinuation methods. Recommendations were based on Grading Recommendations Assessment, Development, and Evaluation, which included the literature, clinical experience and consensus, patient and parent comfort, and costs.

Out of 430 potentially relevant articles, 5 comparative studies were included. Final guideline recommendations were (1) initially observe 3-month-old patients with centered DDH, start abduction treatment if the hip does not normalize after 6–12 weeks; (2) prescribe a Pavlik harness to children <6 months with persisting DDH on repeated ultrasonography, consider alternative abduction devices for children >6 months; (3) assess patients every 6 weeks; and (4) discontinue the abduction device when the hip has normalized or when the child is 12 months.

This paper presents a summary of part 1 of the first evidence-based guideline for treatment of centered DDH in children <1 year. Part 2 presents the guideline on decentered DDH in a separate article.

Postmortem Fetal Temperature Estimation with Magnetic Resonance Imaging: Apparent Diffusion Coefficient Measurements in the Vitreous Body and Cerebrospinal Fluid

OBJECTIVES

Magnetic resonance imaging (MRI) is increasingly used in postmortem fetal imaging. Several factors influence the quality of MRI in this setting, such as small size, autolytic and maceration changes, and temperature. Knowing the fetal temperature at the time of scanning can improve the MRI interpretation. Temperature can be calculated using diffusion-weighted imaging with measurements of the apparent diffusion coefficient (ADC) in the cerebrospinal fluid (CSF). However, this is complicated by small ventricle size and hemorrhage and, therefore, may be unreliable in postmortem imaging. The current study evaluated the feasibility and reliability of using the ADC for temperature measurements of the vitreous body compared to that of CSF.

MATERIALS AND METHODS

Two lambs were scanned postmortem at five different time points over 28 hours. Furthermore, 10 stillborn fetuses were scanned once, at 4 to 62 hours after birth. The temperature was measured with a digital thermometer and calculated using the ADCs of the vitreous body (lambs and fetuses) and CSF (fetuses).

RESULTS

There was an excellent correlation between measured and calculated temperatures in vitreous bodies of lambs (r = 0.997, P < 0.001) and fetuses (r = 0.970, P < 0.001). The correlation between measured and calculated temperatures in the CSF was poor (r = 0.522, P = 0.122).

CONCLUSION

The calculation of the temperature based on the ADC of the vitreous body is feasible and reliable for postmortem fetal imaging.

Structured reporting in radiology: a systematic review to explore its potential

OBJECTIVES

Structured reporting (SR) in radiology reporting is suggested to be a promising tool in clinical practice. In order to implement such an emerging innovation, it is necessary to verify that radiology reporting can benefit from SR. Therefore, the purpose of this systematic review is to explore the level of evidence of structured reporting in radiology. Additionally, this review provides an overview on the current status of SR in radiology.

METHODS

A narrative systematic review was conducted, searching PubMed, Embase, and the Cochrane Library using the syntax 'radiol*' AND 'structur*' AND 'report*'. Structured reporting was divided in SR level 1, structured layout (use of templates and checklists), and SR level 2, structured content (a drop-down menu, point-and-click or clickable decision trees). Two reviewers screened the search results and included all quantitative experimental studies that discussed SR in radiology. A thematic analysis was performed to appraise the evidence level.

RESULTS

The search resulted in 63 relevant full text articles out of a total of 8561 articles. Thematic analysis resulted in 44 SR level 1 and 19 level 2 reports. Only one paper was scored as highest level of evidence, which concerned a double cohort study with randomized trial design.

CONCLUSION

The level of evidence for implementing SR in radiology is still low and outcomes should be interpreted with caution.

KEY POINTS

• Structured reporting is increasingly being used in radiology, especially in abdominal and neuroradiological CT and MRI reports. • SR can be subdivided into structured layout (SR level 1) and structured content (SR level 2), in which the first is defined as being a template in which the reporter has to report; the latter is an IT-based manner in which the content of the radiology report can be inserted and displayed into the report. • Despite the extensive amount of research on the subject of structured reporting, the level of evidence is low.

Holistic processing only? The role of the right fusiform face area in radiological expertise

Radiologists can visually detect abnormalities on radiographs within 2s, a process that resembles holistic visual processing of faces. Interestingly, there is empirical evidence using functional magnetic resonance imaging (fMRI) for the involvement of the right fusiform face area (FFA) in visual-expertise tasks such as radiological image interpretation. The speed by which stimuli (e.g., faces, abnormalities) are recognized is an important characteristic of holistic processing. However, evidence for the involvement of the right FFA in holistic processing in radiology comes mostly from short or artificial tasks in which the quick, ‘holistic’ mode of diagnostic processing is not contrasted with the slower ‘search-to-find’ mode. In our fMRI study, we hypothesized that the right FFA responds selectively to the ‘holistic’ mode of diagnostic processing and less so to the ‘search-to-find’ mode. Eleven laypeople and 17 radiologists in training diagnosed 66 radiographs in 2s each (holistic mode) and subsequently checked their diagnosis in an extended (10-s) period (search-to-find mode). During data analysis, we first identified individual regions of interest (ROIs) for the right FFA using a localizer task. Then we employed ROI-based ANOVAs and obtained tentative support for the hypothesis that the right FFA shows more activation for radiologists in training versus laypeople, in particular in the holistic mode (i.e., during 2s trials), and less so in the search-to-find mode (i.e., during 10-s trials). No significant correlation was found between diagnostic performance (diagnostic accuracy) and brain-activation level within the right FFA for both, short-presentation and long-presentation diagnostic trials. Our results provide tentative evidence from a diagnostic-reasoning task that the FFA supports the holistic processing of visual stimuli in participants’ expertise domain.

Natural Language Processing in Dutch Free Text Radiology Reports: Challenges in a Small Language Area Staging Pulmonary Oncology

Reports are the standard way of communication between the radiologist and the referring clinician. Efforts are made to improve this communication by, for instance, introducing standardization and structured reporting. Natural Language Processing (NLP) is another promising tool which can improve and enhance the radiological report by processing free text. NLP as such adds structure to the report and exposes the information, which in turn can be used for further analysis. This paper describes pre-processing and processing steps and highlights important challenges to overcome in order to successfully implement a free text mining algorithm using NLP tools and machine learning in a small language area, like Dutch. A rule-based algorithm was constructed to classify T-stage of pulmonary oncology from the original free text radiological report, based on the items tumor size, presence and involvement according to the 8th TNM classification system. PyContextNLP, spaCy and regular expressions were used as tools to extract the correct information and process the free text. Overall accuracy of the algorithm for evaluating T-stage was 0,83 in the training set and 0,87 in the validation set, which shows that the approach in this pilot study is promising. Future research with larger datasets and external validation is needed to be able to introduce more machine learning approaches and perhaps to reduce required input efforts of domain-specific knowledge. However, a hybrid NLP approach will probably achieve the best results.

T-staging pulmonary oncology from radiological reports using natural language processing: translating into a multi-language setting

Background

In the era of datafication, it is important that medical data are accurate and structured for multiple applications. Especially data for oncological staging need to be accurate to stage and treat a patient, as well as population-level surveillance and outcome assessment. To support data extraction from free-text radiological reports, Dutch natural language processing (NLP) algorithm was built to quantify T-stage of pulmonary tumors according to the tumor node metastasis (TNM) classification. This structuring tool was translated and validated on English radiological free-text reports. A rule-based algorithm to classify T-stage was trained and validated on, respectively, 200 and 225 English free-text radiological reports from diagnostic computed tomography (CT) obtained for staging of patients with lung cancer. The automated T-stage extracted by the algorithm from the report was compared to manual staging. A graphical user interface was built for training purposes to visualize the results of the algorithm by highlighting the extracted concepts and its modifying context.

Results

Accuracy of the T-stage classifier was 0.89 in the validation set, 0.84 when considering the T-substages, and 0.76 when only considering tumor size. Results were comparable with the Dutch results (respectively, 0.88, 0.89 and 0.79). Most errors were made due to ambiguity issues that could not be solved by the rule-based nature of the algorithm.

Conclusions

NLP can be successfully applied for staging lung cancer from free-text radiological reports in different languages. Focused introduction of machine learning should be introduced in a hybrid approach to improve performance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13244-021-01018-1.

Redefining the structure of structured reporting in radiology

Structured reporting is advocated as a means of improving reporting in radiology to the ultimate benefit of both radiological and clinical practice. Several large initiatives are currently evaluating its potential. However, with numerous characterizations of the term in circulation, “structured reporting” has become ambiguous and is often confused with “standardization,” which may hamper proper evaluation and implementation in clinical practice. This paper provides an overview of interpretations of structured reporting and proposes a clear definition that differentiates structured reporting from standardization. Only a clear uniform definition facilitates evidence-based implementation, enables evaluation of its separate components, and supports (meta-)analyses of literature reports.

Can high school students help to improve breast radiologists in detecting missed breast cancer lesions on full-field digital mammography?

Aim: To investigate whether full-field digital mammography (FFDM) and contrast-enhanced mammography (CEM), evaluated by non-experienced high school students, improves detection of missed breast cancer lesions on FFDM, in the same cohort of patients. Methods: Non-experienced first- and second year high school students examined fourteen cases of patients diagnosed with breast cancer. These cases consisted of missed breast cancer lesions on FFDM by a breast radiologist. Sensitivity of assessment of the students on FFDM and CEM was analysed and compared with the initial results of the breast radiologists. Results: A total of 134 high school students participated in this study. Mean age was 12.8 years (range 10-14). Based on FFDM, mean overall sensitivity of the students was 29.2% (18.9 - 39.6%). When recombined CEM images were used, mean overall sensitivity of students improved to 82.6% (74.0 - 91.2%) (p=0.001). Mean overall sensitivity of FFDM exams evaluated by radiologists was 75.7% (64.2 - 87.3%), which was lower when compared to student's evaluations on recombined CEM exams, yet not statistically significant (p=0.098). Conclusions: Contrast-enhanced mammography evaluated by non-experienced high school students might improve detection rate of breast cancer when compared to evaluations of only full-field digital mammography by radiologists.

Chest X-ray evaluation training: impact of normal and abnormal image ratio and instructional sequence

CONTEXT

Medical image perception training generally focuses on abnormalities, whereas normal images are more prevalent in medical practice. Furthermore, instructional sequences that let students practice prior to expert instruction (inductive) may lead to improved performance compared with methods that give students expert instruction before practice (deductive). This study investigates the effects of the proportion of normal images and practice-instruction order on learning to interpret medical images. It is hypothesised that manipulation of the proportion of normal images will lead to a sensitivity-specificity trade-off and that students in practice-first (inductive) conditons need more time per practice case but will correctly identify more test cases.

METHODS

Third-year medical students (n = 103) learned radiograph interpretation by practising cases with, respectively, 30% or 70% normal radiographs prior to expert instruction (practice-first order) or after expert instruction (instruction-first order). After training, students performed a test (60% normal) and sensitivity (% of correctly identified abnormal radiographs), specificity (% of correctly identified normal radiographs), diagnostic performance (% of correct diagnoses) and case duration were measured.

RESULTS

The conditions with 30% of normal images scored higher on sensitivity but the conditions with 70% of normal images scored higher on specificity, indicating a sensitivity and specificity trade-off. Those who participated in inductive conditions took less time per practice case but more per test case. They had similar test sensitivity, but scored lower on test specificity.

CONCLUSIONS

The proportion of normal images impacted the sensitivity-specificity trade-off. This trade-off should be an important consideration for the alignment of training with future practice. Furthermore, the deductive conditions unexpectedly scored higher on specificity when participants took less time per case. An inductive approach did not lead to higher diagnostic performance, possibly because participants might already have relevant prior knowledge. Deductive approaches are therefore advised for the training of advanced learners.

Diagnostic accuracy of preoperative ultrasonography in predicting contralateral inguinal hernia in children: a systematic review and meta-analysis

Objectives

The incidence of children developing metachronous contralateral inguinal hernia (MCIH) is 7–15%. Contralateral groin exploration during unilateral hernia repair can prevent MCIH development and subsequent second surgery and anaesthesia. Preoperative ultrasonography is a less invasive strategy and potentially able to detect contralateral patent processus vaginalis (CPPV) prior to MCIH development.

Methods

We queried MEDLINE, Embase and Cochrane library to identify studies regarding children aged < 18 years diagnosed with unilateral inguinal hernia without clinical signs of contralateral hernia, who underwent preoperative ultrasonography of the contralateral groin. We assessed heterogeneity and used a random-effects model to obtain pooled estimates of sensitivity, specificity and area under the receiver operating characteristic curve (AUC).

Results

Fourteen studies (2120 patients) were included, seven (1013 patients) in the meta-analysis. In studies using surgical exploration as reference test (n = 4, 494 patients), pooled sensitivity and specificity were 93% and 88% respectively. In studies using contralateral exploration as reference test following positive and clinical follow-up after negative ultrasonographic test results (n = 3, 519 patients), pooled sensitivity was 86% and specificity 98%. The AUC (0.984) shows high diagnostic accuracy of preoperative ultrasonography for detecting CPPV, although diagnostic ultrasonographic criteria largely differ and large heterogeneity exists. Reported inguinal canal diameters in children with CPPV were 2.70 ± 1.17 mm, 6.8 ± 1.3 mm and 9.0 ± 1.9 mm.

Conclusion

Diagnostic accuracy of preoperative ultrasonography to detect CPPV seems promising, though may result in an overestimation of MCIH prevalence, since CPPV does not invariably lead to MCIH. Unequivocal ultrasonographic criteria are mandatory for proper diagnosis of CPPV and subsequent prediction of MCIH.

Key Points

• Diagnostic accuracy of preoperative ultrasonography for detection of CPPV in children with unilateral inguinal hernia is high.

• Preoperative ultrasonographic evaluation of the contralateral groin assumedly results in an overestimation of MCIH prevalence.

• Unequivocal ultrasonographic criteria are mandatory for proper diagnosis of CPPV and risk factor identification is needed to predict whether CPPV develops into clinically apparent MCIH.

Electronic supplementary material

The online version of this article (10.1007/s00330-018-5625-6) contains supplementary material, which is available to authorized users.

Does the Use of a Checklist Help Medical Students in the Detection of Abnormalities on a Chest Radiograph?

The interpretation of chest radiographs is a complex task that is prone to diagnostic error, especially for medical students. The aim of this study is to investigate the extent to which medical students benefit from the use of a checklist regarding the detection of abnormalities on a chest radiograph. We developed a checklist based on literature and interviews with experienced thorax radiologists. Forty medical students in the clinical phase assessed 18 chest radiographs during a computer test, either with (n = 20) or without (n = 20) the checklist. We measured performance and asked participants for feedback using a survey. Participants that used a checklist detected more abnormalities on images with multiple abnormalities (M = 50.1%) than participants that could not use a checklist (M = 41.9%), p = 0.04. The post-experimental survey shows that on average, participants considered the checklist helpful (M = 3.25 on a five-point scale), but also time consuming (M = 3.30 on a five-point scale). In conclusion, a checklist can help medical students to detect abnormalities in chest radiographs. Moreover, students tend to appreciate the use of a checklist as a helpful tool during the interpretation of a chest radiograph. Therefore, a checklist is a potentially important tool to improve radiology education in the medical curriculum.

What We Do and Do Not Know about Teaching Medical Image Interpretation

Educators in medical image interpretation have difficulty finding scientific evidence as to how they should design their instruction. We review and comment on 81 papers that investigated instructional design in medical image interpretation. We distinguish between studies that evaluated complete offline courses and curricula, studies that evaluated e-learning modules, and studies that evaluated specific educational interventions. Twenty-three percent of all studies evaluated the implementation of complete courses or curricula, and 44% of the studies evaluated the implementation of e-learning modules. We argue that these studies have encouraging results but provide little information for educators: too many differences exist between conditions to unambiguously attribute the learning effects to specific instructional techniques. Moreover, concepts are not uniformly defined and methodological weaknesses further limit the usefulness of evidence provided by these studies. Thirty-two percent of the studies evaluated a specific interventional technique. We discuss three theoretical frameworks that informed these studies: diagnostic reasoning, cognitive schemas and study strategies. Research on diagnostic reasoning suggests teaching students to start with non-analytic reasoning and subsequently applying analytic reasoning, but little is known on how to train non-analytic reasoning. Research on cognitive schemas investigated activities that help the development of appropriate cognitive schemas. Finally, research on study strategies supports the effectiveness of practice testing, but more study strategies could be applicable to learning medical image interpretation. Our commentary highlights the value of evaluating specific instructional techniques, but further evidence is required to optimally inform educators in medical image interpretation.

Systematic viewing in radiology: seeing more, missing less?

To prevent radiologists from overlooking lesions, radiology textbooks recommend "systematic viewing," a technique whereby anatomical areas are inspected in a fixed order. This would ensure complete inspection (full coverage) of the image and, in turn, improve diagnostic performance. To test this assumption, two experiments were performed. Both experiments investigated the relationship between systematic viewing, coverage, and diagnostic performance. Additionally, the first investigated whether systematic viewing increases with expertise; the second investigated whether novices benefit from full-coverage or systematic viewing training. In Experiment 1, 11 students, ten residents, and nine radiologists inspected five chest radiographs. Experiment 2 had 75 students undergo a training in either systematic, full-coverage (without being systematic) or non-systematic viewing. Eye movements and diagnostic performance were measured throughout both experiments. In Experiment 1, no significant correlations were found between systematic viewing and coverage, r = -.10, p = .62, and coverage and performance, r = -.06, p = .74. Experts were significantly more systematic than students F2,25 = 4.35, p = .02. In Experiment 2, significant correlations were found between systematic viewing and coverage, r = -.35, p < .01, but not between coverage and performance, r = .13, p = .31. Participants in the full-coverage training performed worse compared with both other groups, which did not differ between them, F2,71 = 3.95, p = .02. In conclusion, the data question the assumption that systematic viewing leads to increased coverage, and, consequently, to improved performance. Experts inspected cases more systematically, but students did not benefit from systematic viewing training.

Skeletal maturity of children with multiple osteochondromas: is diminished stature due to a systemic influence?

BACKGROUND

Multiple ostechondromas (MO) is an autosomal dominant inherited disease caused by mutated exostosin genes. It mostly affects the long bones and can lead to growth disturbances, especially disproportionate short stature. Both the local effect on growth plates and the systemic influence of the gene disorder on growth mechanisms might explain the diminished stature.

PURPOSE

The hypothesis of this study is that the diminished stature in adults with MO is due to a systemic influence, leading to early skeletal maturation and early closure of the growth plate. Therefore, in these patients the skeletal age in adolescence is hypothesized to be higher than the calendar age.

METHODS

Radiographs of the left hand were collected from 50 MO-affected children. The skeletal age was calculated using these radiographs according to the Greulich-Pyle bone scale and was compared to the calendar age at the time of radiography.

RESULTS

Children aged 3-12 years had a significantly lower skeletal age compared to their calendar age (p = 0.030). Children aged 12-17 years had a significantly higher skeletal age (p = 0.019), especially boys. Skeletal maturation in children with MO therefore differs from their peers.

CONCLUSION

In this study, the skeletal age in younger children with MO is lower than their calendar age. For adolescents, particularly boys, this is reversed, suggesting an earlier or faster closure of the growth plates. These findings support a systemic influence of the gene defect on growth rate.

Abusive head trauma: differentiation between impact and non-impact cases based on neuroimaging findings and skeletal surveys

OBJECTIVES

To determine whether imaging findings can be used to differentiate between impact and non-impact head trauma in a group of fatal and non-fatal abusive head trauma (AHT) victims.

METHODS

We included all AHT cases in the Netherlands in the period 2005-2012 for which a forensic report was written for a court of law, and for which imaging was available for reassessment. Neuroradiological and musculoskeletal findings were scored by an experienced paediatric radiologist.

RESULTS

We identified 124 AHT cases; data for 104 cases (84%) were available for radiological reassessment. The AHT victims with a skull fracture had fewer hypoxic ischaemic injuries than AHT victims without a skull fracture (p=0.03), but the relative difference was small (33% vs. 57%). There were no significant differences in neuroradiological and musculoskeletal findings between impact and non-impact head trauma cases if the distinction between impact and non-impact head trauma was based on visible head injuries, as determined by clinical examination, as well as on the presence of skull fractures.

CONCLUSIONS

Neuroradiological and skeletal findings cannot discriminate between impact and non-impact head trauma in abusive head trauma victims.

The male reproductive system in classic galactosemia: cryptorchidism and low semen volume

Previous studies examining reproductive parameters in men with galactosemia have inconsistently demonstrated abnormalities. We hypothesized that men with galactosemia may demonstrate evidence of reproductive dysfunction. Pubertal history, physical examination, hormone levels and semen analyses were examined in 26 males with galactosemia and compared to those in 46 controls. The prevalence of cryptorchidism was higher in men with galactosemia than in the general population [11.6% vs. 1.0% (95%CI: 0.75-1.26; p <0.001)]. Testosterone (461±125 vs. 532± 33 ng%; p=0.04), inhibin B (144±66 vs. 183±52 pg/mL; p=0.002) and sperm concentration (46±36 vs. 112±75×10(6) spermatozoa/mL; p=0.01) were lower and SHBG was higher (40.7±21.5 vs 26.7±14.6; p=0.002) in men with galactosemia compared to controls. Semen volume was below normal in seven out of 12 men with galactosemia. Men with galactosemia have a higher than expected prevalence of cryptorchidism and low semen volumes. The subtle decrease in testosterone and inhibin B levels and sperm count may indicate mild defects in Sertoli and Leydig cell function, but does not point towards severe infertility causing reproductive impairment. Follow-up studies are needed to further determine the clinical consequences of these abnormalities.

Primary ovarian insufficiency in classic galactosemia: role of FSH dysfunction and timing of the lesion

FSH inactivity due to secondary hypoglycosylation has been suggested as a potential mechanism for primary ovarian insufficiency in classic galactosemia. To investigate the role of FSH and to gain insight in the timing of the damage, ovarian stimulation tests were performed and data on ovarian imaging collected. Fifteen patients with primary ovarian insufficiency underwent ovarian stimulation with gonadotropins. Only one patient showed a normal increase in estradiol level, all the others had a low or no estradiol response. Anti-Müllerian hormone measurement in all girls and women showed levels below the detection limit of 0.10 μg/l. Ovarian volumes were evaluated by MRI in 14 patients and compared to age matched controls, prepubertal controls and postmenopausal controls. The ovarian volumes of the galactosemic girls were smaller than those of the age matched controls (p = 0.001) and the prepubertal ovaries (p = 0.008), and did not differ significantly from postmenopausal ovarian volumes (p = 0.161). In conclusion we found no evidence that FSH inactivity plays a role in primary ovarian insufficiency in classic galactosemia. Moreover, ovarian imaging results point to an early onset of ovarian failure in this disease.

Hepatobiliary and pancreatic imaging in children-techniques and an overview of non-neoplastic disease entities

Imaging plays a major role in the diagnostic work-up of children with hepatobiliary or pancreatic diseases. It consists mainly of US, CT and MRI, with US and MRI being the preferred imaging modalities because of the lack of ionizing radiation. In this review the technique of US, CT and MRI in children will be addressed, followed by a comprehensive overview of the imaging characteristics of several hepatobiliary and pancreatic disease entities most common in the paediatric age group.

Birth-related mid-posterior rib fractures in neonates: a report of three cases (and a possible fourth case) and a review of the literature

BACKGROUND

Posterior rib fractures in young children have a high positive predictive value for non-accidental injury (NAI). Combined data of five studies on birth trauma (115,756 live births) showed no cases of rib fractures resulting from birth trauma. There have, however, been sporadic cases reported in the literature.

OBJECTIVE

We present three neonates with both posterior rib fractures and ipsilateral clavicular fractures resulting from birth trauma. A review of the literature is also presented. The common denominator and a possible mechanical aetiology are discussed.

MATERIALS AND METHODS

In total, 13 cases of definitive birth-related posterior rib fractures were identified.

RESULTS

Nearly all (9/10) posterior rib fractures were (as far as reported in the original publications) in the midline. In 12 of the 13 children, birth weight was high and in 7 children birth was complicated by shoulder dystocia. An interesting finding was that in cases where a clavicular fracture was present, this was on the ipsilateral side.

CONCLUSION

Radiologists, when presented with a neonate with posterior rib fractures, should be aware of this rare differential diagnosis.

Multifocal osteomyelitis in a child: a rare manifestation of cat scratch disease: a case report and systematic review of the literature

We present a case of a 9-year-old immunocompetent girl who presented with pain in her left elbow and a painful swelling at her left clavicle. She had no lymphadenopathy or fever. Four hot spots were seen at her left clavicle, proximal and distal left humerus and lumbo-sacral spine on a bone scan. A magnetic resonance imaging showed an inflammatory process with bone destruction at her clavicle. Serological testing and polymerase chain reaction performed on a bone biopsy identified a Bartonella henselae infection. She was treated with rifampin and trimethoprim-sulphamethoxazole. After a relapse half a year later, the patient recovered fully. Multifocal osteomyelitis is a rare manifestation of cat scratch disease in children.

Major brain lesions by intrauterine herpes simplex virus infection: MRI contribution

The majority of neonatal Herpes Simplex Virus (HSV) infections are acquired at birth as a consequence of direct fetal contact with the infected birth canal or through an ascending infection after premature rupture of the amniotic membranes. Intrauterine transmission of HSV infection from mother to the fetus is rare; in only 5% of the cases it occurs from haematogenous transplacental dissemination. We present a case of transplacental intrauterine HSV infection after a primary maternal HSV infection in the first trimester of pregnancy. The diagnosis was assessed by viral culture and serologic tests. Ultrasound imaging revealed fetal brain damage in the third trimester. Finally, the MRI showed the devastating extensiveness of the HSV infection, which was beyond the expectation based on the ultrasound images.

Sonographic genital ambiguity in a fetus due to a mosaic 45,X/46,X,idic(Y)(qter-p11.32::p11.32-qter) karyotype

Nowadays, improved ultrasound techniques enable the detection of more subtle congenital abnormalities at an earlier stage of fetal development. Current cytogenetic techniques can characterize a chromosomal abnormality in greater detail. These advancements in both diagnostic possibilities have helped to answer many questions but have also created new issues and dilemmas in counselling. This is illustrated by this case report of a 35-year-old woman, who presented at the end of the second trimester of her first pregnancy. Sonographic examination indicated an abnormal external genital in a male fetus. A differential diagnosis of hypospadia was made. During follow-up, an amniocentesis was performed, and this showed a 45,X/46,X,idic(Y)(qter-p11.32::p11.32-qter) karyotype as the cause of the sonographic findings. Cytogenetic characterization of the isodicentric Y chromosome and pre- and post-natal findings in the child are reported. Cases with a similar karyotype reported in the literature are reviewed.

[Radiography of the medial ends of the clavicles by the method of the Dutch Immigration and Naturalisation Service is unsuitable for determining adulthood]

OBJECTIVE

A critical examination of the radiological technique used by the Dutch Immigration and Naturalisation Service (IND) for determining the adulthood of persons around the age of 18.

DESIGN

Descriptive.

METHOD

Radiographs of the hands and clavicles were reassessed in 29 asylum seekers (15 boys, 9 girls and 5 persons of unknown gender) in whom the IND suspected a discrepancy between the true age and the age stated. In each case, 1 hand radiograph and 3 clavicular views were taken: 1 posteroanterior standard view as well as 2 oblique views, in order to assess the epiphyses at the medial ends of the clavicles. Additionally, the radiographs of one of these subjects were shown to 241 radiologists and radiologists-in-training.

RESULTS

On all the hand X-rays, the epiphyses were closed. Based on this, the skeletal age of the girls was at least 15 years and 11 months and that of the boys at least 17 years and 3 months. The medial ends of the clavicles could not be assessed on the standard views due to overprojection of the spinal column. In 55 of the 58 films in which the thorax was turned, the direction of the X-rays was not appropriate for assessing the growth plates. The other 3 could not be assessed as there were no existing objective radiological criteria. The assessments of the stage of development as an indication of skeletal age in the cases presented differed greatly from one another.

CONCLUSION

The radiographs that were taken to establish whether or not the asylum seekers were underage were unsuitable for the purpose for which they were taken.

Pulmonary disease assessment in cystic fibrosis: comparison of CT scoring systems and value of bronchial and arterial dimension measurements

PURPOSE

To retrospectively compare thin-section computed tomographic (CT) scores obtained with five scoring systems for assessment of pulmonary disease in children with cystic fibrosis and to determine additional value of bronchial and arterial dimension measurements.

MATERIALS AND METHODS

Scores obtained with five thin-section CT scoring systems were compared. A score of 0 indicated the absence of abnormalities; a higher score meant that more structural abnormalities were seen. Three observers assigned scores and then reassigned scores after intervals varying from 1-2 weeks to 1-2 months at review of thin-section CT scans obtained in 25 children with cystic fibrosis. Interobserver and intraobserver reliability was calculated with intraclass correlation coefficients. Quantitative measurements of bronchial and arterial dimensions were obtained. Thin-section CT scores were correlated (Spearman correlation) with bronchial and arterial dimensions and with results of pulmonary function tests (PFTs), such as forced expiratory volume in 1 second (FEV(1)).

RESULTS

Scores with all five scoring systems were reproducible, with intraclass correlation coefficients of 0.74 and higher (P <.05), and showed significant correlations with FEV(1) (R = -0.73 to -0.69, P <.01). Ratio of bronchial diameter to accompanying pulmonary arterial diameter was correlated with thin-section CT scores but not with FEV(1). Ratio of bronchial wall thickness to accompanying pulmonary arterial diameter was not correlated with thin-section CT scores or PFT results.

CONCLUSION

Thin-section CT scores were reproducible and were correlated with PFT results. Measurements of bronchial dimensions were not significantly related to scores or PFT results.

Ultrasonography of musculoskeletal infections in children

Ultrasonography is an important modality for evaluation of musculoskeletal infections in children because it is rapid, nonionising and very sensitive for (infectious) fluid collections and joint effusions. Moreover, the images are not degraded by metallic or motion artefacts (as with CT and MRI) and finally, ultrasonography offers the possibility of fine-needle aspiration to confirm the infectious nature of a fluid collection without unnecessary contamination of adjacent anatomical compartments. Ultrasonography should be combined with radiography because both imaging techniques are complimentary. The purpose of this article is to emphasise the role of ultrasonography in the diagnosis of various diseases in childhood, including cellulitis, subcutaneous abscess, necrotizing fasciitis, pyomyositis, infectious bursitis and arthritis, osteomyelitis, foreign bodies and infectious lymphadenitis. Along with conventional radiography, ultrasonography is a very valuable modality for early diagnosis and follow-up of musculoskeletal infections in children.

Prenatal testicular torsion: diagnosis and natural course. An ultrasonographic study

The aim of this study was to demonstrate the ultrasonographic features of prenatal torsion of the testis at presentation and during follow-up, with histological correlation post-orchidectomy. Between January 1985 and December 1999, 13 neonates with antenatal torsion of the testis were examined postnatally, at presentation and during follow-up, with high-resolution ultrasonography, including colour Doppler ultrasonography. Bilateral testis volume was evaluated [lengthxwidthxdepthx(pi/6)]. Ultrasonographic findings were correlated with histological findings (n=8) and findings at surgery. Moreover, in 1 patient the affected testis was postoperatively examined with ultrasonography in vitro. These findings were correlated with preoperative ultrasonography and corresponding histological slices. All patients (n=13) presented with a painless congenital scrotal mass. On the affected side no flow was found with colour Doppler ultrasonography. Testis volume on the affected and normal side showed mean values of 2.1 and 0.5 cc, respectively. On ultrasonography all patients showed scrotal swelling and a heterogeneous testis with hypoechoic central areas (necrosis). The tunica albuginea was thickened in all patients, with focal (n=2) or rim-like (n=11) hyperechoic reflections (calcifications) at the transitional zone between testis and tunica albuginea. In 9 patients follow-up ultrasonography showed progressive testis atrophy on the affected side. In 10 patients a contralateral hydrocele was found. Prenatal torsion shows a characteristic ultrasonographic pattern. In newborns with a scrotal mass, these ultrasonographic findings should suggest this diagnosis and delay in immediate surgery and/or oncological work-up may be appropriate.

Benign fibrous histiocytoma of the posterior arch of C1 in a 6-year-old boy: a case report

STUDY DESIGN

Presented is a unique case report of a rare bone tumor: a benign fibrous histiocytoma (BFH) located in the posterior arch of C1 in a 6-year-old child.

OBJECTIVE

To describe a benign fibrous histiocytoma of bone and the differential diagnostic considerations based on the authors' case report.

SUMMARY OF BACKGROUND DATA

A BFH is a rare tumor composed of varying degree of fibroblast-like spindle cells, foam cells, and multinucleated giant cells. Approximately 86 cases have been reported in literature. Its exact nature remains somewhat controversial. A lesion may be designated a benign fibrous histiocytoma based on clinical, radiographic, and microscopic criteria.

MATERIALS AND METHODS

The clinical symptoms, plain radiographs, computerized tomography (CT), magnetic resonance images (MRI), bone scintigraphy, and histologic section of the lesion are discussed, evaluated, and compared with other benign bone lesions.

RESULTS

This case is, to the best of the authors' knowledge, the first benign fibrous histiocytoma to be reported in the cervical spine of a child. Various benign lesions such as nonossifying fibroma, giant-cell tumor, fibrous dysplasia, aneurysmal bone cyst, osteoblastoma, and eosinophilic granuloma are included in the differential diagnosis.

CONCLUSION

Benign fibrous histiocytoma is a rare skeletal tumor. Because of this and its nonpathognomonic microscopic features, the diagnosis can be somewhat troublesome. However, by systematically reviewing patient's symptoms, tumor location, and radiographic and microscopic characteristics, other benign lesions can be eliminated. The diagnosis of a BFH is one of exclusion.

[Diagnostic image (119). A neonate with abnormal distention and vomiting. Meconium ileus and cystic fibrosis]

A female neonate developed abdominal distension with vomiting. She was suffering from meconium ileus and cystic fibrosis.

MRI findings of the pituitary gland in short children born small for gestational age (SGA) in comparison with growth hormone-deficient (GHD) children and children with normal stature

BACKGROUND

Disturbances in the GH/IGF-I axis are reported in 25-60% of short children born small for gestational age (SGA). We hypothesized that these abnormalities might be related to abnormalities in the pituitary region. Therefore, the results of magnetic resonance imaging (MRI) of short SGA children were compared to MRI results of other groups of short children and to normal controls.

PATIENTS AND METHODS

MRI was performed in four groups of short children: SGA children without GH deficiency (SGA group; n = 17), SGA children with isolated GH deficiency (SGA + IGHD group; n = 10), non-SGA children with isolated GH deficiency (IGHD group; n = 24) and non-SGA children with multiple pituitary hormone deficiencies (MPHD group; n = 15). MRI was also performed in children with normal stature (control group; n = 13). Pituitary height (PH) and thickness of the pituitary stalk (PS) were measured and their relationship with the maximum GH peak during a GH stimulation test, serum IGF-I and IGFBP-3 levels was evaluated.

RESULTS

Short SGA children either with or without IGHD did not show major anatomical abnormalities in the hypothalamic-pituitary region in contrast to 58% of the non-SGA IGHD children and 87% of the MPHD children who had anatomical abnormalities. PH in SGA children without GHD was normal whereas it was significantly lower in SGA children with IGHD. The lowest PHs were measured in non-SGA children with MPHD. A moderate decrease in PH was associated with significantly lower maximum serum GH peaks and lower serum IGF-I and IGFBP-3 levels.

CONCLUSION

Measuring PHs in children with less severe GHD, who underwent MRI as part of the diagnostic process, might support the diagnosis of GHD even in the absence of anatomical abnormalities. Our study demonstrates that there is no indication to perform MRI of the pituitary region in short children born SGA without GHD.

Development of a perigraft seroma around modified Blalock-Taussig shunts: imaging evaluation

OBJECTIVE

The modified Blalock-Taussig shunt is a synthetic shunt between the subclavian and pulmonary artery, frequently used in the treatment of children with pulmonary hypoperfusion caused by congenital heart disease. The development of a perigraft seroma is a known complication of this procedure. We sought to describe the imaging features of a perigraft seroma and to define an optimal diagnostic strategy in patients with a suspected perigraft seroma.

MATERIALS AND METHODS

Between January 1993 and December 1998, 96 children underwent 105 modified Blalock-Taussig shunt procedures. In eight children, 11 cases of perigraft seromas were identified. The mean age of these children at the time of operation was 3 years (range, 6 days to 5 years 8 months). Pre- and postoperative chest radiographs were routinely performed in the children in whom seromas had been found. Additional postoperative radiologic investigations consisted of thoracic sonography (in 11 cases), CT (in eight cases), and MR imaging (in two cases). In all cases of perigraft seroma, the modified Blalock-Taussig shunts were constructed through a posterolateral thoracotomy at the fourth intercostal space.

RESULTS

On average, the chest radiographs showed the first signs of the seroma on day 10 after the surgery (range, day 1-day 30). Using thoracic sonography, it was possible to visualize the perigraft seroma and the modified Blalock-Taussig shunt in eight (73%) of 11 cases. CT and MR imaging performed equally well in revealing perigraft seromas.

CONCLUSION

As was found in these critically ill children, sonography has an advantage over CT and MR imaging because of its portability and, therefore, capability for bedside use. We recommend the use of sonography as the initial imaging modality in suspected cases of perigraft seroma development.

Prenatal prediction of pulmonary hypoplasia: clinical, biometric, and Doppler velocity correlates

OBJECTIVES

To determine the value of pulmonary artery Doppler velocimetry relative to fetal biometric indices and clinical correlates in the prenatal prediction of lethal lung hypoplasia (LH) in prolonged (>1 week) oligohydramnios.

METHODS

Forty-two singleton pregnancies with oligohydramnios associated with premature rupture of membranes ([PROM]; n = 31) or bilateral renal pathology (n = 11) were examined using color-coded Doppler ultrasound in a cross-sectional study design. Mean gestational age was 28.0 +/- 4.3 weeks (range: 20-36 weeks). Thoracic, cardiac, and abdominal circumference and the largest vertical amniotic fluid pocket were measured. Pulsed Doppler measurements of the arterial pulmonary branches were made at the level of the cardiac 4-chamber view. Diagnosis of LH was based on clinical, radiologic, and pathologic criteria. Clinicians were blinded to the prenatal measurements.

RESULTS

The prevalence of lethal LH was 43%. In the PROM subset, combination of onset of PROM at <or =20 weeks, duration of oligohydramnios at > or =8 weeks, and degree of oligohydramnios at < or =1 cm presented the highest clinical prediction rate for lethal LH. For both the total group and the PROM subset, the highest prediction rate for lethal LH was presented by thoracic circumference/abdominal circumference ratio, peak systolic velocity in the proximal branch, and time-averaged and end-diastolic velocity in the middle branch of the pulmonary artery. In the PROM subset, the combination of all 3 clinical, biometric, and Doppler parameters revealed the most favorable combination to predict lethal LH (positive predictive value: 100%; accuracy: 93%; and sensitivity: 71%).

CONCLUSION

Doppler velocimetry may detect changes in pulmonary artery waveforms in the presence of LH but fails to be the ultimate test for the prenatal prediction of lethal LH. The best prediction can be achieved by combining clinical, biometric, and Doppler parameters.