Two-Dimensional Echocardiography Estimates of Fetal Ventricular Mass throughout Gestation.

BACKGROUND: Two-dimensional (2D) ultrasound quality has improved in recent years. Quantification of cardiac dimensions is important to screen and monitor certain fetal conditions. We assessed the feasibility and reproducibility of fetal ventricular measures using 2D echocardiography, reported normal ranges in our cohort, and compared estimates to other modalities. METHODS: Mass and end-diastolic volume were estimated by manual contouring in the four-chamber view using TomTec Image Arena 4.6 in end diastole. Nomograms were created from smoothed centiles of measures, constructed using fractional polynomials after log transformation. The results were compared to those of previous studies using other modalities. RESULTS: A total of 294 scans from 146 fetuses from 15+0 to 41+6 weeks of gestation were included. Seven percent of scans were unanalysable and intraobserver variability was good (intraclass correlation coefficients for left and right ventricular mass 0.97 [0.87-0.99] and 0.99 [0.95-1.0], respectively). Mass and volume increased exponentially, showing good agreement with 3D mass estimates up to 28 weeks of gestation, after which our measurements were in better agreement with neonatal cardiac magnetic resonance imaging. There was good agreement with 4D volume estimates for the left ventricle. CONCLUSION: Current state-of-the-art 2D echocardiography platforms provide accurate, feasible, and reproducible fetal ventricular measures across gestation, and in certain circumstances may be the modality of choice

Novel Applications and Refinements of Ultrasound Techniques in Perinatal and Infant Death Investigation

The decline in parental consent for perinatal autopsies has led to the development of less invasive autopsy techniques, primarily using imaging and in some cases acquiring tissue samples through laparoscopic techniques via small incisions. Whilst post-mortem MRI (PMMR) has been extensively tested, and shown to be a suitable modality for determining the cause of death/demise in the perinatal cohort, it is not widely available. This thesis explores the utility of a poorly explored, yet more accessible, cheaper, dynamic imaging modality widely used in ‘live’ paediatric imaging for the purposes of a less invasive autopsy – the perinatal post-mortem ultrasound (PMUS). I present a systematic review of the limited literature of PMUS diagnostic accuracy for perinatal death investigation encompassing 4 publications with 455 cases in total. This reveals an overall pooled whole body sensitivity rate of 73.3% [95% CI 59.9, 83.5] and specificity rate of 96.6% [95% CI 92.6, 98.4] . A comprehensive imaging protocol for whole body PMUS is also presented based on my own experience in scanning 272 perinatal deaths. An analysis in 130 of these cases with autopsy as a reference standard, showed that brain and abdominal diagnoses yielded the highest sensitivity rates (90.9% and 92.3% respectively), with spinal, cardiac and thoracic diagnoses yielding the lowest sensitivity rates (50%, 50% and 57.1% respectively). Imaging of the brain and heart however were the least likely to be of diagnostic quality (76.8% and 78.3% diagnostic cases respectively), particularly in macerated fetuses. In a subset of cases where PMUS and 1.5T PMMR were performed, there was no significant difference in whole body diagnostic accuracy rates (concordance rates for PMUS versus PMMR of 86.4% [95%CI 77.7, 92.0] versus 88.6% [95% CI 80.3, 93.7]), although PMMR yielded fewer non-diagnostic brain and cardiac examinations (2.9% and 2.9% non-diagnostic brain and cardiac PMMR cases versus 22.8% and 14.7% non-diagnostic PMUS cases). In the second part of my thesis, I describe the development of an ‘incisionless’ ultrasound guided biopsy method using a single entry site for the biopsy needle – the umbilical vein. This ‘INTACT’ biopsy method allowed for a ‘non-invasive’ autopsy with tissue sampling, with a biopsy success rate of 76.1% overall for all organs, with highest individual organ success rates >90% for heart and lungs. I conclude by discussing how best to incorporate PMUS into clinical practice and suggest areas for future researc

Ultrazvučna procjena cirkumferencije fetalnog srca kao prediktor gestacijske dobi

Introduction: Ultrasound is a non-invasive imaging modality, safe for both the mother and the fetus, which uses a high frequency sound to generate images of body tissues and organs. It has been widely used for fetal evaluation and dating. Purpose: To determine normative values of fetal heart circumference (FHC) as a predictor of the gestational age (GA) in black population and compare it to those of the Caucasian population. Material and Methods: A prospective cross-sectional study was carried at the University of Maiduguri Teaching Hospital (UMTH), Nigeria. 324 women with a singleton pregnancy between 12-40 weeks, who conceived naturally, were scanned using a 2D ultrasound machine with a 3.5 MHz curvilinear probe. Two fetal heart diametersat right angle to each other were taken at the level of the four-heart chamber view, during diastole. Results: There is a strong positive linear correlation between the FHC and the GA (r2= 0.964, p<0.001). The equation of GA prediction is Y=0.246X + 5.06 (where y=GA, X=FHC). FHC weekly growth rate is 3.81mm. FHC is more accurate between 12-20 weeks GA and its accuracy decreases as the pregnancy progresses. There is a strong correlation between FHC and biparietal diameter (BPD) (r2=0.959), HC(r2=0.946) and FL (r2= 0.962). Conclusion: The study has derived a nomogram of FHC as a predictor of the GA in Nigerian population and has shown that the FHC is a good predictor of GA especially in the early second trimester. Also, there was a statistically significant difference between the FHC in our study population (blacks) and those of the Caucasian population.Uvod: Ultrazvuk je neinvazivni način snimanja, siguran za majku i fetus, koji upotrebljava visokofrekventne zvučne valove za stvaranje slika tjelesnih tkiva i organa. Uvelike se primjenjuje za fetalnu procjenu i datiranje. Svrha: Utvrditi normativne vrijednosti cirkumferencije fetalnog srca (FHC) kao prediktora gestacijske dobi (GA) u populaciji crnaca i usporediti je s onom kod bijelaca. Materijali i metode: Prospektivna presječna studija provedena je u Sveučilišnoj bolnici Maiduguri u Nigerija. 324 žene s jednoplodnom trudnoćom između 12 i 40 tjedna trudnoće, koje su začele prirodnim putem, pregledane su s pomoću 2D ultrazvučnog aparata sa zakrivljenom sondom od 3,5 MHz. Snimljena su dva promjera fetalnog srca pod desnim kutom na razini prikaza četiriju srčanih komora tijekom dijastole. Rezultati: Postoji snažna pozitivna linearna korelacija između cirkumferencije fetalnog srca (engl. fetal heart circumference – FHC) i gestacijske dobi (engl. gestational age – GA) (r2 = 0,964, p < 0,001). Jednadžba za predviđanje gestacijske dobi jest Y = 0,246X + 5,06 (gdje je y = GA, X = FHC). Tjedna stopa rasta FHC-a iznosi 3,81 mm. FHC je točniji između 12 i 20 tjedna gestacije i njegova se točnost smanjuje kako trudnoća odmiče. Postoji jaka korelacija između FHC-a i biparijetalnog promjera (engl. biparietal diameter – BPD) (r2 = 0,959), HC (r2 = 0,946) i duljine bedrene kosti (engl. femoral length – FL) (r2 = 0,962) Zaključak: Studija je rezultirala izradom nomograma FHC-a kao prediktora gestacijske dobi u nigerijskoj populaciji i pokazala je da je FHC dobar prediktor gestacijske dobi, posebno u ranom drugom tromjesečju. Također, postojala je statistički značajna razlika između FHC-a u našoj istraživanoj populaciji (crnci) i populaciji bijelaca

NOVO U PROSUDBI VIŠEPLODNIH TRUDNOĆA 3D/4D ULTRAZVUKOM

Introduction of ultrasound has revolutionized the antenatal diagnosis of multiple pregnancies. Indeed, two-dimensional sonography (2D) is still the primary modality for the diagnosis and evaluation of multiple pregnancies. However, 2D sonography may be replaced by three- (3D) and four-dimensional (4D) sonography whenever appropriate. New technique should be accepted as a complementary to 2D sonography, because additional information which assists in the clinical management could sometimes be provided. 3D sonography improves counting of gestational sacs, without any risk of undercounting even for less experienced ultrasonographers. The rate of determinations of appropriate chorionicity by 3D is almost 100% in the second and in the third trimester, as it enables the achievement of »perfectly« oriented picture, which is not always the case with 2D. 3D US improves the visualization of both twins, while the use of volumetric calculations might improve the diagnosis of discordant growth. It also improves the diagnostic capability by offering more diagnostic information in the detection and the evaluation of fetal malformations of the cranium, face, spine, extremities and body surface. 3D and 3D power Doppler permit depiction of curvatures of the umbilical cord and visualization of the number of loops involved in entanglement. The main benefits of 4D sonography include: accurate recognition of an isolated motor activity of a single fetus; distinguishing between spontaneous and stimulated motor activity; and spatial visualization of the inter-twin area. By 4D US, types of movements, isolated movements of each twin or high order multiples, inter-twin contacts and interactions can be easily recognized from early gestation. Studies have shown that twins were at approximately 4-fold increased risk for cerebral palsy compared with singletons, which is important, but not yet solved issue. 4D US is undoubtedly a new powerful imaging tool whose potential in scientific and clinical area should be searched for. In the meantime true clinical value of this new modality should be neither underestimated nor overestimated.Uvođenje ultrazvuka predstavljalo je veliku pomoć u antenatalnoj dijagnozi višeplodnih trudnoća. Dvodimenzionalni (2D) ultrazvuk je doista još uvijek najvažnija metoda u dijagnostici i praćenju višeplodnih trudnoća, a on se može dopuniti trodimenzionalnim (3D) ili četverodimenzionalnim (4D) ultrazvukom kad god je to neophodno. Novije ultrazvučne tehnike valja prihvatiti kao komplementarne 2D tehnici, jer mogu doprinijeti dobivanju nekih novih spoznaja koje katkada mogu pomoći u kliničkoj procjeni. Primjenom 3D ultrazvuka poboljšava se određivanje broja gestacijskih vrećica, bez bojazni da će se njihov broj podcijeniti čak i u slučaju kad pretragu izvodi neiskusan pretraživač. Određivanje korioniciteta pomoću 3D ultrazvuka će dostići gotovo 100% točnost u drugom i trećem tromjesečju, obzirom da 3D omogućuje dobivanje odlično orijentirane slike, što se međutim ne postiže uvijek pomoću 2D ultrazvuka. 3D poboljšava prikaz obaju dvojaka, dok će primjena volumetrijskih mjerenja poboljšati dijagnozu diskordantnog rasta. Osim toga 3D poboljšava mogućnost otkrivanja prirođenih malformacija, jer se njime mogu prikazati mnoge pojedinosti na različitim dijelovima tijela, te se tako pomoću 3D ultrazvuka češće otkrivaju malformacije kranijuma, lica, kralježnice, ekstremiteta i površine tijela. 3D ultrazvuk i 3D osnaženi dopler omogućuju prikaz petlji pupkovine te broj petlji koje sudjeluju u omatanju pupkovine. Najvažnije prednosti 4D ultrazvuka uključuju: mogućnost prenatalnog otkrivanja pojedinačnih pokreta jednoga od dvojaka, razlikovanje spontane i stimulirane motoričke aktivnosti te zoran prikaz prostora između dvojaka. Osim toga pomoću 4D ultrazvuka se može odrediti vrsta pokreta, pokreti svakog ploda iz višeplodnih trudnoća pojedinačno, a međusobni kontakti i interakcije plodova se mogu vrlo jednostavno prikazati već od najranije gestacijske dobi. Istraživanjima je dokazano četverostruko povećanje rizika pojave cerebralne paralize u djece rođene iz višeplodnih trudnoća u usporedbi s onima rođenim iz jednoplodnih trudnoća, što je važno, no još uvijek neriješeno pitanje. 4D ultrazvuk je nesumnjivo nova metoda prikaza čije mogućnosti u znanstvenom i kliničkom području valja i dalje istraživati. U međuvremenu vrijednost ove nove metode ne bi trebalo ni podcijeniti niti precijeniti

Volumetric growth of the lungs in human fetuses: an anatomical, hydrostatic and statistical study

PURPOSE: The prenatal assessment of lung volume is becoming increasingly important in determining survival in both preterm infants and newborns affected by pulmonary hypoplasia. This study aimed to examine the lung volumes in the human fetus at varying gestational ages. MATERIALS AND METHODS: Using anatomical, hydrostatic (water displacement according to Archimedes’ patent) and statistical methods (one-way ANOVA test for paired data and post-hoc Bonferroni test, Kolmogorov–Smirnov test, Levene’s test, Student’s t test, regression analysis), volumes of the right and left lungs were measured in 67 human fetuses of both sexes (35 males, 32 females) aged 16–25 weeks, derived from spontaneous abortions and stillbirths. RESULTS: No male–female differences concerning the right and left pulmonary volumes were found. The mean volume of the right lung increased from 1.43 ± 0.25 to 8.45 ± 2.66 cm(3), according to the cubic function y = –1.592 + 0.0007 × age(3) ± 0.851 (R(2) = 0.84). The volumetric growth of the left lung, from 1.24 ± 0.22 to 6.78 ± 3.03 cm(3), followed the cubic model y = –1.110 + 0.0005 × age(3) ± 0.794 (R(2) = 0.78). The total pulmonary volume increased from 2.67 ± 0.47 to 15.22 ± 5.58 cm(3), in accordance with the cubic model y = –2.729 + 0.0012 × age(3) ± 1.598 (R(2) = 0.83). The mean volumes of the right and left lungs accounted for 54.9 ± 2.0 and 45.1 ± 2.0 %, respectively, of the total lung volume. CONCLUSIONS: No sex differences are found between the lung volumes in the fetus. The growth of fetal lung volume follows a three-degree polynomial function. Throughout the analyzed period the two lungs grow proportionately to each other, with the volumetric predominance of the right lung. The lung volumes in the fetus are of great relevance in the evaluation of the normal pulmonary growth and the diagnosis of pulmonary hypoplasia

Transabdominal ultrasonographic evaluation of fetal well-being in the late-term mare and cow

In the equine practice, attempts have been made to examine the fetus in the second and third trimester of pregnancy but all of the available methods have limitations. Until now, transabdominal ultrasonography has been regarded as the most informative examination. This method allows us to measure fetal heart rate, fetal activity as well as the quality and quantity of the fetal fluids. A modified biophysical profile for horses was used by several researchers in the USA from the 1990s as a gold standard. However, it is not sensitive enough and, in the authors’ experience, professionals can face difficulties during its application (e.g. for measuring aortic diameter and fetal breathing movements). In cows, this method was first used for this purpose by a Canadian research group in 2007. They reported that transabdominal ultrasound was promising but showed low sensitivity in this species. The present studies show that birth weight cannot be predicted from fetal aortic diameter measurement in cows as suggested by other researchers. Transabdominal ultrasound needs special equipment (2–3.5 MHz convex transducer) and basic ultrasonographic knowledge; however, we suggest that in most cases it can be performed with the dam placed in a stock and without shaving the examination area. The method provides useful information within 30–40 minutes, enabling the examiner to determine whether or not the fetus is alive and to recognise placentitis or twins. This technique also allows measuring the combined thickness of the uteroplacental unit, and the authors’ ongoing study showed higher normal values in Lipizzaner mares compared to values in other breeds. In conclusion, with the help of advanced techniques, simple and low-cost methods should be developed for the evaluation of the pregnant dam and its fetus to assess fetal viability in the veterinary practice