Week Of Fetal Life Research Articles

Ectopic Cervical Thymus in Adult: An Incidental Finding.

Thymus is a paired organ which develops during the sixth week of fetal life, attains maximum size by three years and involutes in adult life. Anatomically it is situated in superior mediastinum. Thymus can be present at ectopic sites like neck, skull base, middle ear, submandibular gland and tonsil. Ectopic Cervical Thymus (ECT) is very rare in adults and can present as a solid mass, cyst or thymoma. ECT occurs due to failure of descent during embryonic development. ECT can mimic any pathologic mass, metastatic deposit or lymph node enlargement. We report a case of ECT discovered incidentally in an adult during histopathological examination of thyroid carcinoma. In addition, we described the role of immunohistochemistry markers to confirm the various thymic components.

Anatomical Variations of Spleen in South Indian Population

Background: Spleen is the large lymphoid organ that is situated in the left hypochondriac region and is usually wedge shaped. It has two ends, two surfaces and three margins. Superior margin of the spleen possesses characteristic notches. Normally spleen is not palpable. It develops in dorsal mesogastrium during the 5th week of fetal life from a mass of mesenchymal cells. Objectives: The present study explains the morphology of spleen 1.To determine the length of spleen 2.To determine the breadth of spleen 3.To determine the thickness of spleen 4.To determine the variations in notches & shape of spleen 5.To compare the morphometric measurements with previous studies Results: In our study, the length, breadth and thickness of spleen was 9.19 cm, 6.61 cm and 3.25 cm respectively. The length of spleen ranged between 5-8cm in 35% of spleens, 8.1-10cm in 35%, 10.1-12cm in 24%and >12.1cm in 6% of spleens studied. Majority of the length of spleens ranged between 5-8cm and 8.1-10cm. The breadth ranged between 3.5-5.5cm in 25% of spleens, 5.6-7.5cm in 45%, 7.6-9.5cm in 20% and 9.6-11.5cm in 10% of spleens studied. The maximum range of breadth of spleen was 5.6-7.5cm in our study. The thickness of spleen ranged between 1-4cm in 82% of spleens, 4.1-6cm in 10% of spleens and 6.1-8cm in 8% of spleen maximum being 1-4cm. 5 fissures and 6 lobules in one of the spleens were observed. These fissures were from the superior border. A deep fissure on the diaphragmatic surface was also observed. The shape of spleen was wedge shaped in 34 % of the spleens being the maximum and next was oval shaped spleens and heart shaped spleens and crescent shaped spleens were the least found in 1% only. The weight of the spleen ranged between 40-500gms, heaviest being 461.1 gms in one of the spleen and least being 47.8gms. Conclusion: The detailed knowledge on variations of spleen is important in clinical practice to avoid and prevent any complications and to obtain a good operative, as well as diagnostic intervention. Keywords: Splenic notches, Polysplenia, Wandering spleen

Case Series of Acute Abdomen with Midgut Malrotation Presenting in Adulthood

Introduction: Intestinal malrotation (IM) is a congenital anomaly due to partial or complete failure of the 270° counter-clockwise rotation of the midgut around the superior mesenteric vessels in 5th to 12th week of fetal life. Midgut malrotation usually presents as an emergency in the 1st month of life or within infancy. Adult cases are rarely reported and usually present with chronic nonspecific symptoms. Here, we present a case series of acute abdomen with midgut malrotation presenting in adulthood that came to the Department of Surgical Gastroenterology of a tertiary hospital in Salem, Tamil Nadu. Case Summary: Four patients presented with acute abdominal complaints, diagnosed, and proceeded with emergency laparotomy. Three patients had abdominal abnormalities unrelated to coexisting IM, and the other one showed sequelae of IM with Ladd's band and obstruction. Except the first patient, all other patients improved well postoperatively and were discharged without complications. Conclusion: IM should be considered in differential diagnosis of acute abdomen and bowel obstruction in adults. IM may be encountered as an incidental imaging/laparotomy finding or be the cause of acute abdomen.

Clinicopathological profile of paediatric vitellointestinal duct anomalies

Background: Vitellointestinal duct (VID) or Omphalomesenteric duct (OMD) is the embryonic connection between the yolk sac and the primitive midgut. Anomalies result from failure of the involution of the VID. Normally, it obliterates between the fifth and seventh weeks of fetal life. They include Meckel’s diverticulum (MD), fibrous band, fistula, sinus tract, cyst, and umbilical polyp. Symptomatic cases require surgical correction. They are characterised by different clinical presentations and histological appearances. This study gathers a single paediatric institutional experience of VID remnants, their demographic, clinical profile, varied histomorphology including the presence of ectopic tissues. Aims and Objectives: The objective of this study was to retrospectively review all the symptomatic cases of VID abnormalities at a tertiary pediatric referral hospital. The demographic profile, clinical presentation, and histopathology were reviewed and descriptively analyzed. We classified these anomalies based on embryology and histology. The findings of this study will provide insights to pathologists and treating clinicians less exposed to these rare lesions. Materials and Methods: Data was retrieved retrospectively from the pathology records of a tertiary paediatric referral institute for 3 years. Histological slides of VID anomalies were reviewed and a descriptive analysis of the findings was performed. A thorough review of the literature was also done on these very rare lesions and their findings compared to our results. Results: A total of 60 cases of VID anomalies were encountered during the study period. There was significant male preponderance. The most common age group at surgery was infancy. MD was the commonest VID anomaly. The least common was vitelline fistula and only a single case was encountered in the study period. Ectopic tissues were seen in 25% of the cases and included gastric and colonic mucosae and pancreatic tissue. Conclusion: The histopathology of VID anomalies provides an interesting diagnostic experience for the reporting pathologist. Awareness of the embryology, presentation and histology of these lesions aids in accurate diagnosis.

How Well Do We Know Neonatal Stroke: A Literature Review

Neonatal stroke can be characterized as a cerebrovascular injury that happens between 20 weeks of fetal life and 28 days post-pregnancy life. The assessed frequency of neonatal stroke is between one of every 1600 and one out of 3000 live births which recommends that the neonatal period is the most engaged lifetime time of hazard for stroke. Utilizing the advances in neuroimaging which have assisted with characterizing explicit neonatal stroke sickness states, several topics consisting of pathophysiology, manifestation, diagnosis, and management of neonatal stroke are systematically reviewed in this study. The results confirm several points, namely: (1) Neonatal stroke is characterized as one of six explicit sickness states based on clinical show and neuroimaging discoveries. (2) Intense indicative assortments normally present with seizures, while assumed neonatal stroke assortments typically present with hemiparetic cerebral paralysis. (3) Across all types of neonatal stroke, causative systems are ineffectively perceived, featuring the requirement for extra investigations just as an alert in allotting causation.

Growth rate of thyroid gland in human fetus

Objectives to determine the thyroid gland growth rate in the intermediate fetal period of human ontogenesis.
 Material and methods. The thyroid glands of 60 male and female fetuses aged from 14 to 27 weeks were the subject of this research. The material was divided according to fetus age in three groups: Group I from 14 to 18 weeks, Group II from 19 to 22 weeks and Group III from 23 to 27 weeks.
 Results. The study revealed the increase in all dimensions of thyroid gland related to the increase of fetus age. During the intermediate fetal period of ontogenesis, the growth varied from 19% (for the anteroposterior isthmus size) to 59% (for the right lobe height). The thyroid gland growth rate for different sex groups varied between 24% and 60% in female fetuses, in male fetuses from 20% to 57%. Besides, the thyroid lobes and isthmus of female fetuses grew at a higher rate than those of the male fetuses. The uneven growth of the anatomical structure was also registered when comparing different age groups within the intermediate fetal period. The highest rate of thyroid gland growth was observed starting from the 22nd week of fetal life; until the 19th week the growth rate ranged between 7% (isthmus) and 25% (right lobe). The study of the thyroid gland growth rate in female and male fetuses in different age groups revealed identical tendencies involving the active growth of thyroid gland dimensions starting from the 22nd week.

“NOT AT HOME” !!!

A Bochdalek hernia is a posterior congenital defect of the diaphragm, usually on the left hemidiaphragm, caused by a lack of closure of the pleuroperitoneal canal between the eighth and tenth week of foetal life during the embryonic development. It typically presents in the neonatal period with severe respiratory failure. Incidental diagnosis in an asymptomatic patient presenting in adult life is rare. We report a case of an asymptomatic eighteen year old male who was incidentally discovered to have congenital diaphragmatic hernia when he was operated for testicular torsion on an emergency basis.

Second Branchial Cleft Cyst: A Case Report

Objective: Branchial anomalies are congenital pathologies that are seen in the lateral region of the neck and are generally benign. The branchial clefts develop in the 2nd-7th weeks of fetal life as embryonal development. The branchial anomalies are caused by non-disappearance, abnormal development and, incomplete emerger of the branchial clefts and pockets during embryonal development. The branchial anomalies are generally seen as the cyst. The most common cyst was the second branchial cleft cyst with 95%. Their diameter is usually a few centimeters.
 Case: A 37-year old male patient was admitted to the hospital because of a swelling on the left side of his neck for four years. Physical examination revealed a mobile cystic mass in level 2 at the upper left jugular region of the neck. The cystic mass and the surrounding lymph nodes were excised and sent to the pathology laboratory. A cystic mass, approximately 5x4x3.5 cm in size, containing cystic areas was observed macroscopically. Microscopically, the cyst was lined with squamous epithelium and contained large lymphocyte groups in the subepithelial area. The case was reported as the branchial cleft cyst.
 Conclusion: Branchial cleft cysts should be excised before reaching large sizes, as they may cause pain and pressure on the surrounding tissue. In addition, it should be kept in mind that malignancy may develop from branchial cleft cysts, although rare.

Development of the interatrial wall during the ontogenesis of foetuses and children up to one year of age.

The foramen ovale, present in foetal interatrial septum, plays an important role during foetal life. During delivery, foramen ovale closes and becomes fossa ovalis, starting the pulmonary circulation. The aim of our study was to describe the growth of the interatrial wall and changes in location of the foramen ovale, and fossa ovalis during the ontogenesis in the human hearts. The study was performed on post-mortem material obtained from 92 human hearts from 22nd week of foetal life up to 1 year of age, fixed in a 4% formalin solution. The interatrial wall size in the studied development period was greater in the horizontal than in the vertical dimension. During ontogenesis up to 1 year old, the anterior and inferior parts of the interatrial wall increased their shares considerably by 8% and 6%, respectively. The percentage participation of foramen ovale in the interatrial wall construction in the foetal period formed more than 50% of its size and fairly decreased reaching in infants about 39%. Our study demonstrated that during ontogenesis, from the foetal period to infancy, the parts of the interatrial wall increase their dimensions unevenly. The foramen ovale growth is smaller, compared to the rest of the interatrial wall development. On the basis of our data we can assume that the foramen ovale centre tends to be found in the postero-inferior quadrant of the interatrial wall (foetuses) and in postero-superior quadrant of the interatrial wall - in infants.

The development of the human uterus: morphogenesis to menarche.

There is emerging evidence that early uterine development in humans is an important determinant of conditions such as ontogenetic progesterone resistance, menstrual preconditioning, defective deep placentation and pre-eclampsia in young adolescents. A key observation is the relative infrequency of neonatal uterine bleeding and hormone withdrawal at birth. The origin of the uterus from the fusion of the two paramesonephric, or Müllerian, ducts was described almost 200 years ago. The uterus forms around the 10th week of foetal life. The uterine corpus and the cervix react differently to the circulating steroid hormones during pregnancy. Adult uterine proportions are not attained until after puberty. It is unclear if the endometrial microbiome and immune response-which are areas of growing interest in the adult-play a role in the early stages of uterine development. The aim is to review the phases of uterine development up until the onset of puberty in order to trace the origin of abnormal development and to assess current knowledge for features that may be linked to conditions encountered later in life. The narrative review incorporates literature searches of Medline, PubMed and Scopus using the broad terms individually and then in combination: uterus, development, anatomy, microscopy, embryology, foetus, (pre)-puberty, menarche, microbiome and immune cells. Identified articles were assessed manually for relevance, any linked articles and historical textbooks. We included some animal studies of molecular mechanisms. There are competing theories about the contributions of the Müllerian and Wolffian ducts to the developing uterus. Endometrium features are suggestive of an oestrogen effect at 16-20 weeks gestation. The discrepancy in the reported expression of oestrogen receptor is likely to be related to the higher sensitivity of more recent techniques. Primitive endometrial glands appear around 20 weeks. Features of progestogen action are expressed late in the third trimester. Interestingly, progesterone receptor expression is higher at mid-gestation than at birth when features of endometrial maturation are rare. Neonatal uterine bleeding occurs in around 5% of neonates. Myometrial differentiation progresses from the mesenchyme surrounding the endometrium at the level of the cervix. During infancy, the uterus and endometrium remain inactive. The beginning of uterine growth precedes the onset of puberty and continues for several years after menarche. Uterine anomalies may result from fusion defects or atresia of one or both Müllerian ducts. Organogenetic differentiation of Müllerian epithelium to form the endometrial and endocervical epithelium may be independent of circulating steroids. A number of genes have been identified that are involved in endometrial and myometrial differentiation although gene mutations have not been demonstrated to be common in cases of uterine malformation. The role, if any, of the microbiome in relation to uterine development remains speculative. Modern molecular techniques applied to rodent models have enhanced our understanding of uterine molecular mechanisms and their interactions. However, little is known about functional correlates or features with relevance to adult onset of uterine disease in humans. Prepubertal growth and development lends itself to non-invasive diagnostics such as ultrasound and MRI. Increased awareness of the occurrence of neonatal uterine bleeding and of the potential impact on adult onset disease may stimulate renewed research in this area.

Refining the resolution of craniofacial dysmorphology in bipolar disorder as an index of brain dysmorphogenesis

As understanding of the genetics of bipolar disorder increases, controversy endures regarding whether the origins of this illness include early maldevelopment. Clarification would be facilitated by a ‘hard’ biological index of fetal developmental abnormality, among which craniofacial dysmorphology bears the closest embryological relationship to brain dysmorphogenesis. Therefore, 3D laser surface imaging was used to capture the facial surface of 21 patients with bipolar disorder and 45 control subjects; 21 patients with schizophrenia were also studied. Surface images were subjected to geometric morphometric analysis in non-affine space for more incisive resolution of subtle, localised dysmorphologies that might distinguish patients from controls. Complex and more biologically informative, non-linear changes distinguished bipolar patients from control subjects. On a background of minor dysmorphology of the upper face, maxilla, midface and periorbital regions, bipolar disorder was characterised primarily by the following dysmorphologies: (a) retrusion and shortening of the premaxilla, nose, philtrum, lips and mouth (the frontonasal prominences), with (b) some protrusion and widening of the mandible-chin. The topography of facial dysmorphology in bipolar disorder indicates disruption to early development in the frontonasal process and, on embryological grounds, cerebral dysmorphogenesis in the forebrain, most likely between the 10th and 15th week of fetal life.

SAT-478 A Case of Congenital Thyroid Hemi-Agenesis- Caution for Complications!

Introduction: Congenital Thyroid hemi-agenesis is an uncommon clinical entity. We present a case highlighting the importance of awareness of this condition and the need to evaluate and manage co-existing hypothyroidism and risk of malignancy. Case: A 20 year old female known to have Hashimoto’s thyroiditis (non-adherent to levothyroxine), and hemi-agenesis of left lobe of thyroid gland, presented with right-sided thyroid enlargement. She was clinically euthyroid. Physical exam: enlarged right sided thyroid gland with palpable anterior cervical lymphadenopathy. Left lobe could not be palpated. TFTs were notable for TSH 4.98 uIU/ml (0.358-3.74) and Free T4 0.79 ng/dl (0.76-1.46) consistent with sub-clinical hypothyroidism while Anti TPO antibody was positive at 8332.8 U/mL (0 - 60). CBC negative for leukocytosis. US thyroid: left-sided thyroid agenesis with intact isthmus and enlargement of right lobe of the thyroid 7.7 cm x 1.6 cm x 2.6 cm with 2 sub-centimeter hypoechoic solid nodules and 2 enlarged lymph nodes 1.5 cm and 2.3 cm (not found in US thyroid 2 years ago) Levothyroxine was re-started. ENT evaluation determined that her lymphadenopathy was benign and consistent with Hashimoto’s thyroiditis. Subsequent TFTs improved. Discussion: Thyroid Gland embryogenesis occurs in the 4th week of fetal life. Subsequent abnormal bilobal differentiation of the thyroid gland is presumed to be the etiology of congenital hemi-agenesis. Its prevalence in several studies is estimated to be between 0.05-0.25%. It is symptomatic pre-dominantly in females and may have familial origin with vast majority of cases having left hemi-agenesis with intact isthmus. It is helpful to know that most symptomatic patients have compensatory hypertrophy of the remnant lobe. It is important to remember that compensatory enlargement of the remnant lobe in the setting of hypothyroidism may be a sign of insufficient endogenous thyroxine production and/or replacement. Although rarely symptomatic, hemi-thyroid remnant may need to be evaluated for co-existing hyperthyroidism, hypothyroidism, carcinoma and multinodular goiter among others, with hypothyroidism thought to be the most common. US thyroid is a useful modality to help guide the evaluation of patients with hemi-agenesis. Awareness of this congenital condition is key in preventing unnecessary evaluations and interventions. Non-resolving lymphadenopathy in Hashimoto’s thyroiditis must be evaluated for lymphoma, however, based on studies, no additional risk of malignancy was identified in patients with underlying thyroid hemi-agenesis.

Morphometric study of the diaphragmatic surface of the liver in the human fetus.

This study aimed to examine age-specific reference intervals and growth dynamics of the best fit for liver dimensions on the diaphragmatic surface of the fetal liver. The research material consisted of 69 human fetuses of both sexes (32♂, 37♀) aged 18–30 weeks. Using methods of anatomical dissection, digital image analysis and statistics, a total of 10 measurements and 2 calculations were performed. No statistical significant differences between sexes were found (p>0.05). The parameters studied displayed growth models that followed natural logarithmic functions. The mean value of the transverse–to–vertical diameter ratio of the liver throughout the analyzed period was 0.71±0.11. The isthmic ratio decreased significantly from 0.81±0.12 in the 18–19th week to 0.62±0.06 in the 26–27th week, and then increased to 0.68±0.11 in the 28–30th week of fetal life (p<0.01). The morphometric parameters of the diaphragmatic surface of the liver present age-specific reference data. No sex differences are found. The transverse–to–vertical diameter ratio supports a proportionate growth of the fetal liver. Quantitative anatomy of the growing liver may be of relevance in both the ultrasound monitoring of the fetal development and the early detection of liver anomalies.

A plausible pathway of imprinted behaviors: Skin-to-skin actions of the newborn immediately after birth follow the order of fetal development and intrauterine training of movements

We hypothesize that the competence of a newborn in the first hours after birth is the direct result of behavior training that begins during the first 12 weeks of fetal life. Correlation of Widström’s 9 Instinctive Stages (behaviors of the full-term newborn during the first hours after birth) with the developmental movements during fetal life demonstrate that the fetus is invested in learning specific tasks, in a specific order, that are evolutionarily necessary for survival during the first hour and beyond.

1355 Accessory Spleen: An Unusual Pancreatic Mass Posing a Diagnostic Dilemma

INTRODUCTION: There are two main causes of accessory spleen; failure of fusion of the splenic anlage during the fifth week of fetal life and following autotransplantation after a splenectomy. They are structurally identical to the spleen and are most commonly found in the splenic hilum or pancreatic tail. Although rarely noted on radiograph due to low spatial resolution, their detection is increasing with more advanced modalities. This can result in the finding of a pancreatic mass that poses a diagnostic dilemma. CASE DESCRIPTION/METHODS: The patient is a 62-year-old man with a history of hepatitis B infection. On routine surveillance he had ultrasound findings of a liver calcification with inability to determine the presence of cirrhosis and a mildly elevated alpha-fetoprotein level. He was sent for an MRI, which revealed a 2.3 × 1.9 cm mass in the pancreatic tail showing mild hyperintense T2 signal and hypointense T1 signal. A CT from 2011 showed a slight contour bulge to the pancreatic tail in the same region, without appreciation of a discrete lesion. He underwent EGD with endoscopic ultrasound (EUS). A 21.4 × 13.7 mm well-circumscribed, homogeneous lesion was found in the pancreatic tail and biopsied. The pathology shows an immunohistochemical-staining pattern consistent with splenic tissue, confirming the diagnosis of an intrapancreatic accessory spleen (IPAS). No further intervention was needed and the patient was sent home. DISCUSSION: Pancreatic cancer has a 5-year survival rate of 9%, therefore it is imperative that all pancreatic masses are investigated thoroughly and promptly. In cases of an IPAS, its differentiation from a pancreatic mass is difficult as splenic tissue can mimic pancreatic tumors, especially on MRI. It is essential to differentiate between the two as IPAS are only clinical relevant when there is torsion, rupture, hemorrhage, or the patient carries a diagnosis of idiopathic thrombocytopenic purpura requiring the removal of all splenic tissue. Imaging modalities such as ultrasound, CT, MRI, and scintigraphy can aid in the diagnosis of IPAS. However, these have limitations and have not shown to provide a definitive diagnosis. EUS with fine needle aspiration is being increasingly used to characterize pancreatic lesions. In this case, it enabled adequate tissue sampling while avoiding unnecessary procedures. This case illustrates another use for EUS in an otherwise difficult diagnostic scenario.

Splenunculi-frequency and characteristics in patients at a tertiary care hospital of Wayanad district

Background: Splenunculi, in other words a supernumerary spleen or accessory spleen is a small well defined mass of splenic tissue found separate from the main spleen. It is a congenital entity. The splenunculi generally are the result of failure of fusion of the primordial splenic buds in the dorsal mesogastrium during the 5th week of fetal life. Splenunculi are generally asymptomatic. Rarely they can be a cause of left upper abdominal pain. The study was to evaluate the frequency and characteristics of splenunculi in patients undergoing Computerised tomography of the abdomen in our hospital. Methods: An observational study was carried out in a hospital in Wayanad District between May 2019 to October 2019 (6 months). 256 consecutive patients were included in the study who belonged to the age groups between 11 and 90 years. Patients with a history of abdominal trauma, previous abdominal surgery, abdominal malignancies and haematological disorders were excluded from the study. Each study was systematically analysed for the presence or absence of splenunculi. If present, the number, location, size and shape were assessed and tabulated. Results: A total of 273 abdominal CT scans done from May 2019 to October 2019 were analyzed. 256 cases were included in the study. The most common age group was between 50-70 years. Among the 256 subjects, 70 had splenunculi (27%). Majority of the splenunculi were solitary (76%). One subject had four and another had five splenunculi. Most of the splenunculi were less than 5mm and were oval in shape. The commonest location was at the splenic hilum and lower pole of the spleen (36% each). Conclusion: The frequency of splenunculi was more compared to other studies. The most common location was at the splenic hilum and lower pole. Majority of the splenunculi were solitary and less than 5mm in size.

Duodenal Stenosis with Diaphragmatic Hernia—A Rare Combination—Delayed Diagnoses with Barium Study

AbstractDuodenal stenosis is part of a spectrum of disorders due to non-cannulization of the fetal gut lumen occurring in 11 to 13 weeks of fetal life. The diagnosis is often made in the neonatal period owing to bilious vomiting. The authors present a case of a 9-year-old boy who was diagnosed by an upper gastrointestinal study that showed a hugely dilated stomach filled with food residue and a dilated first part of the duodenum with an abrupt narrowing in the second part of the duodenum in keeping with duodenal stenosis. There was no associated malrotation (a known association), but the delayed images showed a surprising finding of herniation of large bowel loops into the thorax suggestive of a congenital diaphragmatic hernia (Bochdalek type). Both these findings were confirmed on surgery, and the patient underwent duodenoduodenostomy and diaphragmatic hernia repair and is doing well on follow-up. This case is unusual due to the rare association of duodenal stenosis with congenital diaphragmatic hernia and delayed diagnosis. Both these pathologies most often present in the neonatal period, and delayed diagnosis is most often seen with associated trisomy 21 that was not the case in our patient.

Correlation of calvicular length with femur length for estimation of gestational age in fetus in a tertiary institute

Introduction: Accurate determination of gestational age has become important for deciding the appropriate time for termination of the pregnancy as well as to monitor the fetal growth during the entire period of pregnancy. The clavicle begins ossification between the fifth and sixth week of fetal life. Measurement of the clavicle is of special interest since it permits not only the estimation of gestational age, but also the detection of severe congenital anomalies. The purpose of this study is to correlate the fetal clavicular with gestational age during pregnancy [2,3].

Mathematical models of human cerebellar development in the fetal period

The evaluation of cerebellar growth in the fetal period forms a part of a widely used examination to identify any features of abnormalities in early stages of human development. It is well known that the development of anatomical structures, including the cerebellum, does not always follow a linear model of growth. The aim of the study was to analyse a variety of mathematical models of human cerebellar development in fetal life to determine their adequacy. The study comprised 101 fetuses (48 males and 53 females) between the 15th and 28th weeks of fetal life. The cerebellum was exposed and measurements of the vermis and hemispheres were performed, together with statistical analyses. The mathematical model parameters of fetal growth were assessed for crown-rump length (CRL) increases, transverse cerebellar diameter and ventrodorsal dimensions of the cerebellar vermis in the transverse plane, and rostrocaudal dimensions of the cerebellar vermis and hemispheres in the frontal plane. A variety of mathematical models were applied, including linear and non-linear functions. Taking into consideration the variance between models and measurements, as well as correlation parameters, the exponential and Gompertz models proved to be the most suitable for modelling cerebellar growth in the second and third trimesters of pregnancy. However, the linear model gave a satisfactory approximation of cerebellar growth, especially in older fetuses. The proposed models of fetal cerebellar growth constructed on the basis of anatomical examination and objective mathematical calculations could be useful in the estimation of fetal development.

The sequence of lanugo pattern development on the trunk wall in human fetuses.

Due to a growing interest in developmental disorders, and in the long-term skin appendage diseases, both in the cosmetic industry and among specialists in dermatology (broadly defined), there is an increasing number of papers on hair development. The publications by the present team of authors are part of this trend. The aim of the study was to describe the topography and typology of skin pilosity patterns in human fetuses. A total of 278 fetuses (141 male and 137 female) were qualified for the study. The gestational age ranged from 69 to 226 days after conception. All fetuses were taken from a local collection. The study revealed that the first single hairs occur on the posterior wall of the trunk in the 17th week of fetal life, and on the anterior wall between the 18th and 19th week. It was found that in human fetuses lanugo appears statistically significantly later on the skin of the anterior of the trunk than on its posterior. The difference in absolute time is almost 2 weeks of fetal life. No other differences were found in the development cycle of lanugo on the anterior and posterior walls of the trunk. A full pattern was first observed on the posterior wall of the trunk in a fetus in the 19th week, and on the anterior wall in the 21st week. It was found that the process of lanugo development was completed on the posterior wall in the 23rd week, and on the surface of the abdomen in the 26th week. The lanugo developmental cycle, consisting in the appearance of the first single hairs, then partial hair and subsequently the formation of final patterns, is the same on both walls of the trunk.