Microsurgical anatomy of the spinal cord in human fetuses.

PURPOSE: To determine the microsurgical features of the spinal cord and ventral and dorsal rootlets in fetal period. METHODS: Twelve formalin-fixed fetuses (six females and six males) with a mean gestational age of 27.0 ± 2.04 weeks (range between 25 and 32 weeks) were dissected to evaluate morphological properties of the spinal cord and rootlets. RESULTS: Length and width of each spinal cord segment, number of dorsal and ventral rootlets, length of dorsal root entry and ventral root exit zones of each spinal nerve, spinal cord termination level, and the whole spinal cord length were determined in all fetuses. Contrary to previous reports, the number of ventral rootlets was always more than that of dorsal rootlets in all segments. No statistically significant gender difference was found for all parameters. Rootlet number and segment width in cervical region were larger than those of thoracic, while the lengths of dorsal root entry and ventral root exit zones in thoracic region were longer than those of cervical. In lumbar region, dorsal and ventral rootlet numbers were increasing again, while lengths of dorsal root entry and ventral root exit zones were decreasing. Number of dorsal and ventral rootlets of C5 and C6 segments was statistically higher than other cervical segments. The mean spinal cord length was found as 105.55 ± 11.30 mm and there was a positive significant relationship with gestational age. Conus medullaris level was detected between L1 and L3 segments. CONCLUSION: Detailed microsurgical data about the fetal spinal cord and the dorsal and ventral rootlets presented in this study provide significant information which may be essential during surgical interventions in early postnatal period and childhood targeting the spinal cord and spinal nerve roots.

Cavernous sinus and abducens nerve in human fetuses near term.

A long tortuous course of the abducens nerve (ABN) crossing a highly curved siphon of the internal carotid artery is of interest to neurosurgeons for cavernous sinus surgery. Although a "straight" intracavernous carotid artery in fetuses can change into an adult-like siphon in infants, there is no information on when or how the unique course of ABN is established. Histological observations of 18 near-term fetuses (12 specimens of frontal sections and 6 specimens of sagittal sections) demonstrated the following: (I) the ABN consistently took a straight course crossing the lateral side of an almost straight intracavernous carotid artery; (II) the straight course was maintained when sympathetic nerves joined; (III) few parasellar veins of the developing cavernous sinus separated the ABN from the ophthalmic nerve; and (IV) immediately before the developing tendinous annulus for a common origin of extraocular recti, the ABN bent laterally to avoid a passage of the thick oculomotor nerve. Since the present observations strongly suggested morphologies at birth and in infants, major angulations of the ABN as well as the well-known course independent of the other nerves in the cavernous sinus seemed to be established during childhood. In the human body, the ABN might be a limited example showing a drastic postnatal change in course. Consequently, it might be important to know the unique course of ABN before performing endovascular interventions and skull base surgery for petroclival and cavernous sinus lesions without causing inadvertent neurovascular injuries to neonates or infants.

The investigation of the carrying angle of the elbow in fetal period.

PURPOSE: The aim of our study was to determine the carrying angle in human fetuses and to identify variations in carrying angle by gender, fetal age and elbow side in fetal period. METHODS: This study was carried out on 20 dead human fetuses (13 males, 7 females) fixed with formaldehyde, aged between 10-35 weeks of gestation, without external anomalies. Ages of the fetuses were determined according to the general growth parameters. First, the fetus arms were positioned in 180° extension and the forearms were placed in supination. Then the midpoints of the caput humeri, the elbow joint and the wrist were determined. The photographs were taken from the anterior aspect. The distances between the reference points and carrying angles were measured using ImageJ program in the photographs. RESULTS: The mean ± SD values of carrying angle were 14.18 ± 5.52 and 8.21 ± 4.82 degrees in males and in females, respectively. Although there was no difference between right and left sides within both genders, there was a significant difference between genders (p < 0.05). Gestational age and fetal carrying angle showed a medium negative correlation at the right arm and a weak negative correlation at the left arm. CONCLUSION: The existence of a significant difference between fetal carrying angles belong to different genders suggested that the sexual dimorphism of carrying angles may be starting at the early intrauterine period. The carrying angle should be explained with the studies performed in larger series in the prenatal and postnatal periods.

Anatomic and histological analyses of chiasma plantare and long flexor tendons of the foot on human fetuses.

PURPOSE: The aim of present study was to reveal slip transfers related to flexor hallucis longus (FHL) and flexor digitorum longus (FDL) by dissection and to investigate detailed structure of chiasma plantare composed of FHL-FDL tendons and quadratus plantae (QP), with precise composition of the long flexor tendons of lesser toes by histological sections in human fetuses. METHOD: Slip transfers related to FHL and FDL tendons were identified and the related morphometric measurements were taken with dissection in 28 formalin-fixed fetuses (25-40 weeks). Composition and restoration of chiasma plantare and long flexor tendons of lesser toes were traced histological by analyzing movements of the tissues on the sequential coronal sections in five fetuses in the third trimester. The numbers of layers constituting chiasma plantare and the muscles that formed layers were specified. Each of two to five flexor tendons arising from the chiasma plantare was analyzed regarding its formation and contribution of FHL slip. RESULTS: Slip transfers were found as FHL slip in 86% and cross-connections in 14%. The ratios of the slip width to that of FHL and FDL tendons were found higher than in adult literature. Variance in the involvement of slip to FDL and QP, formation and layering of chiasma plantare and formation of long flexor tendons from chiasma plantare were revealed and great similarities were found with data from dissection of adult in literature. CONCLUSION: Slip transfers between FHL and FDL tendons, and layering properties of chiasma plantare were largely finalized during intrauterine period, while structural changes in slip seem to continue in the later stages of life, possibly by the effects of growth and usage of the extremity. In addition to individual variations, investigating the contribution of FHL slip, FDL and QP to long flexor tendons by different methods in literature is also suggested to be responsible for some diversities of our histological study.

Quantitative anatomy of the ilium's primary ossification center in the human fetus.

PURPOSE: An understanding of the development of the ilium's primary ossification center may be useful in both determining the fetal stage and maturity, and for detecting congenital disorders. This study was performed to quantitatively examine the ilium's primary ossification center with respect to its linear, planar and volumetric parameters. MATERIALS AND METHODS: Using methods of CT, digital-image analysis and statistics, the size of the ilium's primary ossification center in 42 spontaneously aborted human fetuses of crown-rump length (CRL) ranged from 130 to 265 mm (aged 18-30 weeks) was studied. RESULTS: With no sex and laterality differences, the best fit growth dynamics for the ilium's primary ossification center was modelled by the following functions: y = - 63.138 + 33.413 × ln(CRL) ± 1.609 for its vertical diameter, y = - 59.220 + 31.353 × ln(CRL) ± 1.736 for its transverse diameter, y = - 105.681 + 1.137 × CRL ± 16.035 for its projection surface area, and y = 478.588 + 4.035 × CRL ± 14.332 for its volume. The shape of the ilium's primary ossification center did not change over the study period, because its transverse -to- vertical diameter ratio was stable at the level of 0.94 ± 0.07. Conclusions The size of the ilium's primary ossification center displays neither sex nor laterality differences. The ilium's primary ossification center grows logarithmically with respect to its vertical and transverse diameters, and linearly with respect to its projection surface area and volume. The shape of the ilium's primary ossification center does not change throughout the examined period. The obtained quantitative data of the ilium's primary ossification center is considered normative for respective prenatal weeks and may contribute to the prenatal ultrasound diagnostics of congenital defects.

Fetal intraluminal portion of the sphincter of Oddi: a histological study using human fetuses

The sphincter of Oddi surrounds a common duct after joining of the bile and pancreatic ducts in the adult ampulla of Vater, but the fetal development of the submucosal portion of the sphincter is still obscure possibly because previous studies used horizontal or frontal sections. We examined serial sagittal histological sections of 12 human fetuses with 36-65 mm crown rump length or CRL (approximately 9-11 weeks) and semi-serial sections of the other 3 fetuses with 210-250 mm (25-30 weeks). Except for 1 fetus (36 mm CRL), fourteen fetuses carried the "intraluminal portion" protruding and floating in the duodenal lumen. Twelve of them had the sphincter extending to the anal side in the duodenal lumen, whereas two extended to the stomach side. The distal end of the sphincter seemed to detach from the duodenal mucosa at and around 9 weeks, and subsequently the common duct seemed to elongate freely without mucosal attachment in mid-term fetuses and, finally, become embedded again in the duodenal mucosa in the postnatal life. A possible discrepancy in growth rate between the sphincter muscle and duodenal mucosa was likely to allow the specific intermediate morphology, i.e., the intraluminal common duct. The fetal accessory papilla did not show such morphology. A minority of cases whose common duct extended to the stomach side might connect with abnormal union of the bile and pancreatic ducts

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Caracterização morfológica e imuno-histoquímica de lesões em casos de aborto bovino bacteriano e viral no sul de Minas Gerais / Morphological and immunohistochemical characterization of the lesions in cases of bacterial and viral bovine abortion in southern Minas Gerais, Brazil

O presente estudo avaliou a participação de agentes bacterianos e virais em abortos em bovinos de propriedades rurais do sul de Minas Gerais. Foi realizada análise histopatológica e imuno-histoquímica dos casos de aborto recebidos pelo Setor de Patologia Veterinária da Universidade Federal de Lavras no período de 1999 a 2013. De 60 fetos analisados, em 30 (50%) foram observadas lesões microscópicas. Destes, oito apresentavam lesões compatíveis com infecção por agentes bacterianos e três apresentaram lesões sugestivas de agentes virais. Dos abortos bacterianos, um feto tinha lesões compatíveis com leptospirose, caracterizadas por icterícia e colestase, nefrite intersticial linfoplasmocítica e nefrose tubular. Sete fetos apresentaram pneumonia ou broncopneumonia purulenta; num deles havia também pleurite e peritonite fibrinosas; e em dois desses fetos houve imunomarcação para Brucella abortus. Dos três fetos com lesões sugestivas de aborto viral ocorreu imunomarcação anti-Herpesvírus bovino em um. Os resultados demonstram a ocorrência de abortos de origem bacteriana e viral na Região do estudo e que medidas profiláticas devem ser adotadas nas propriedades. O trabalho demonstra também que a imuno-histoquímica (IHQ); associada à histopatologia; é uma ferramenta útil e viável para o diagnóstico, especialmente quando provas microbiológicas e/ou sorológicas não estão disponíveis.

The paper evaluates the participation of bacterial and viral agents in bovine abortions in farms of southern Minas Gerais state, Brazil. Histopathological and immunohistochemical analysis was performed in aborted fetuses of cattle received by the Setor de Patologia Veterinária, Universidade Federal de Lavras, from 1999 to 2013. From 60 fetuses studied, 30 (50%) had microscopic lesions. From these, eight had lesions consistent with bacterial agents and three had lesions suggestive of viral agents. In the bacterial abortions, one fetus presented lesions compatible with leptospirosis, characterized by jaundice, cholestasis, lymphoplasmacytic intersticial nephritis, and tubular nephrosis. Seven fetuses had purulent pneumonia or bronchopneumonia and one of them had also fibrinous pleuritis and peritonitis; two of them presented positive immunostaining for Brucella abortus. One of the three fetuses with lesions of viral infection revealed positive imunostaining for bovine herpesvirus. The results showed that abortions of bacterial and viral origin occur in the Region of this study and prophylactic measures should be adopted on the farms. This study also demonstrates that immunohistochemistry associated with histopathology is a useful and viable tool for the diagnosis, especially when microbiological and/or serological tests are not available.

Quantitative description of the morphology and ossification center in the axial skeleton of 20-week gestation formalin-fixed human fetuses using magnetic resonance images.

OBJECTIVES: Human tissues are usually studied using a series of two-dimensional visualizations of in vivo or cutout specimens. However, there is no precise anatomical description of some of the processes of human fetal development. The purpose of our study is to develop a quantitative description of the normal axial skeleton by means of high-resolution three-dimensional magnetic resonance (MR) images, collected from six normal 20-week-old human fetuses fixed in formaldehyde. METHODS: Fetuses were collected after spontaneous abortion and subsequently fixed with formalin. They were imaged using a 1.5 T MR scanner with an isotropic spatial resolution of 200 µm. The correct tissue discrimination between ossified and cartilaginous bones was confirmed by comparing the images achieved by MR scans and computerized axial tomographies. The vertebral column was segmented out from each image using a specially developed semi-automatic algorithm. RESULTS: Vertebral body dimensions and inter-vertebral distances were larger in the lumbar region, in agreement with the beginning of the ossification process from the thoracolumbar region toward the sacral and cephalic ends. CONCLUSION: In this article, we demonstrate the feasibility of using MR images to study the ossification process in formalin-fixed fetal tissues. A quantitative description of the ossification centers of vertebral bodies and arches is presented.

The motor branches of median and ulnar nerves that innervate superficial flexor muscles: a study in human fetuses.

PURPOSE: We aimed to describe the distribution of the motor branches of the median and ulnar nerves that innervate the superficial flexor muscles in detail, as well as to determine any communication between these two nerves in a series of 100 human fetuses. METHODS: This study was performed on 200 upper limbs from 100 fetuses. However, the motor branches of the median nerve were determined on 50 upper limbs because of the developmental properties of medial epicondylar muscles. RESULTS: The motor branch, which innervates the pronator teres, is classified into two types and four subtypes. The flexor carpi radialis branch arose as a single branch in 30% of the cases. The innervation of the flexor digitorum superficialis was also performed by a single muscular branch in 88% of the cases and by two branches in 12% of the cases. The ulnar nerve was classified into two types according to the number of muscular branches in the forearm. Martin-Gruber anastomosis was observed in 7.5% of the cases. CONCLUSIONS: These results show differences from classical definitions regarding the muscular branching patterns of the median and ulnar nerves. We suggest revisiting the classical descriptions of innervation patterns of pronator teres, palmaris longus and flexor carpi radialis muscles, since the variations observed in their innervation patterns are more diverse than has been described.

Nuchal translucency and lymphatic system maldevelopment.

We describe the histological examination of 18 aborted fetuses that had increased nuchal translucency (NT) between 11(+0) and 13(+6) weeks' gestation. The aim of this study was to assess the corresponding NT anatomic features by immunohistochemical (IHC) investigation. A morphological study was performed using lymphatic and blood endothelial specific markers, as well as smooth muscle actin (SMA). We found that all 18 cases were D2-40 positive, CD31 positive, and CD34 negative, suggesting the presence of nuchal lymph vessel ectasia. We found that 12/18 cases were SMA staining positive and 6/18 cases were SMA negative, suggesting that 6/18 cases had nuchal cystic lymphangiectasia, whereas 12/18 had cystic hygromas. The present data seem to confirm the reasonable hypothesis that lymphangiogenesis plays a relevant role in nuchal edema, increased NT, and that increased NT is the result of a lymphatic malformation or a delayed development of the lymphatic system.

Nasal bone length in human fetuses by X-ray.

BACKGROUND: To construct a normal range for the prenatal nasal bone length (NBL) in Brazilians irrespective to the knowledge of the ethnic genetic background. STUDY DESIGN: We studied 35 human fetuses (20 males, 15 females) ranging from 14 to 22 weeks of gestation. Gestational age (GA), crown-rump length (CRL), foot length (FL) and body mass (BM) were measured. The X-ray of the head lateral view was made with the specimens placed directly on the film and the NBL was measured. The NBL was correlated with the GA, the CRL, the FL, and the BM using log-transformed data and the allometric model log y=log a+b log x. RESULTS: Correlations of the NBL growth with GA, CRL, FL, and BM were positive and significant (P<0.05), but NBL vs. BM showed the smallest R indicating this correlation as of little practical use. No sexual dimorphism in the NBL growth in the second trimester fetuses was observed. The NBL grew with positive allometry relative to GA, CRL and BM, but it was allometrically slightly negative relative to the FL in both genders. The NBL be allometrically positive against GA, CRL and BM means the bone grew with growth rates higher than those indices in the period analyzed, but not against FL. CONCLUSION: NBL could be considered an auxiliary measurement in the assessment of the 2nd trimester fetal development because its strong correlation with GA, CRL and FL, even when nothing is known about the ethnicity of the population.

Evaluation of 2407 fetuses in a Turkish population.

OBJECTIVES: Congenital anomalies and intrauterine fetal death (IUFD) are frequent problems in pregnancies. Detection of the etiology is important for genetic counseling, and presenting the geographic distribution of the causes of disorders is necessary for a national policy on precautions. Here, we report the findings of terminated fetuses due to IUFD and congenital anomalies in Turkish population. METHODS: Physical examinations of fetuses and genetic evaluations of families were done. X-ray studies and autopsy were done in the event of necessity. Findings of these studies were combined with prenatal ultrasound results. All cases were classified according to ICD-10. RESULTS: The number of fetuses examined was 2407. Out of these, 1268 fetuses had congenital anomalies. Neurologic anomalies and musculoskeletal system malformations were the most frequent disorders. Specific diagnoses were possible in 64% of all multiple malformation syndromes. Abnormal findings were detected in 18.8% of IUFD fetuses. Nine percent had congenital anomalies and 5.2% had cord complications. The percentage of twins and triplets was 7.5% and 13% of them had anomalies. CONCLUSION: Postmortem evaluation is useful to detect findings necessary for genetic counseling. Our protocol is effective especially in fetuses with congenital anomalies but it can detect only some of the fetal reasons in IUFD cases. A more detailed protocol is needed to investigate IUFD cases.

Upregulated and prolonged differentiation potential of the ependymal cells lining the ventriculus terminalis in human fetuses.

The ventriculus terminalis (VT) is a dilated cavity within the conus medullaris of the spinal cord. Although the VT was discovered in the mid-nineteenth century, little is known about its characteristics during development in human fetuses. Ependymal cells lining the cavities within the CNS retain high differentiation potential, and are believed to be responsible for the postnatal neurogenesis. To evaluate the differentiation capacity of the ependymal cells lining the VT during development, we examined glial fibrillary acidic protein (GFAP) and proliferating cell nuclear antigen (PCNA) expression in the spinal cord of 18-24-week-old human fetuses. GFAP is a marker for the degree of ependymal cell differentiation in the human fetus, and PCNA is a well-known marker for cell division. Morphological characteristics of the VT were also examined. At the lower portion of the conus medullaris, the central canal abruptly expands dorsally to become the VT. Then the VT widens bilaterally while its anteroposterior diameter reduces gradually in a caudal direction. Finally, the VT becomes a narrow, transverse slit at the level of the lowermost conus medullaris. Compared with those lining the central canal, more numerous ependymal cells lining the VT showed more intensive GFAP and PCNA expression throughout all gestational ages examined. This suggests that, in the developing human spinal cord, ependymal cells lining the VT retain their differentiation potential, including a higher proliferative capacity, until a later stage of development than those lining the central canal.

Isolamento de Campylobacter jejuni em feto ovino abortado: relato de caso / Isolation of Campylobacter jejuni from ovine aborted fetus: case report

Relata-se o isolamento de Campylobacter jejuni de um feto ovino abortado no terço final da gestação. Em uma semana, observaram-se quatro casos de aborto em ovelhas com quatro meses de gestação. Imediatamente após o terceiro aborto, um dos fetos foi submetido a exame patológico, quando se realizou a colheita do conteúdo do abomaso para análise bacteriológica. A necropsia, somente foram evidenciadas alterações autolíticas. Apenas na microaerofilia encontrou-se crescimento bacteriano puro com características morfo-tintoriais de Campylobacter sp., identificado fenotípica e molecularmente como C. jejuni. Alerta-se para a possibilidade de quadros de abortos em ovinos serem causados por esse patógeno.

Human prenatal nasal bone lengths: normal standards and length values in fetuses with cleft lip and cleft palate.

OBJECTIVE: The aim of this study was to present prenatal autopsy standards for nasal bone length in normal fetuses, as well as to compare nasal bone lengths in human fetuses with cleft lip and palate with those standards. MATERIAL AND METHODS: The material consisted of human fetuses investigated in connection with diagnosed and legally approved abortions and spontaneous abortions; 40 were normal and 26 had cleft lip and palate (7 isolated cleft lip, 12 isolated cleft palate, and 7 combined cleft lip and palate). Menstrual ages (MA) ranged from 12 to 25 weeks, crown-rump length (CRL) from 55 to 210 mm and foot length (FL) from 7 to 44 mm. All fetuses were radiographed in lateral projection, and, using these images, the nasal bone lengths were measured with a digital caliper. Regression analyses were performed. RESULTS: Standards for normal nasal bone length at different ages are expressed as menstrual age, crown-rump length, or foot length. Comparisons with normal standards showed that the isolated cleft lip group had a significantly smaller nasal bone length than the normal fetuses had. Fetuses with isolated cleft palate and fetuses with combined cleft lip and palate showed no significant deviation from normal standards. CONCLUSION: Normal nasal bone standards can contribute to information on deviations in nasal bone length for aborted fetuses with known and unknown genotypes. The differences in nasal bone lengths in fetuses with different lip and palate clefting can contribute to understanding the pathogenesis of cleft lip and palate.

Polygonal deformation of the dural sac in lumbar epidural lipomatosis: anatomic explanation by the presence of meningovertebral ligaments.

BACKGROUND AND PURPOSE: In patients with epidural lipomatosis, axial lumbar spine CT and MR images occasionally reveal a geometric, polygonal or stellar, shape of the dural sac. The purpose of this study was to define the anatomic structures responsible for this radiologic appearance. We hypothesized that meningovertebral ligaments could anchor the dura mater to the osteofibrous walls of the spinal canal and account for the geometric deformation of the dural sac. METHODS: The epidural spaces were examined in 15 adult cadaveric and seven aborted fetal lumbar spines. For macroscopic studies, 70 adult vertebral segments were separated and dissected by removing the extradural fat. For microscopic examination, axial histologic sections were obtained from 35 fetal and five adult undissected vertebral segments. RESULTS: Meningovertebral ligaments were observed in the median, paramedian, and lateral aspects of the anterior and posterior epidural spaces of both adult and fetal lumbar spines. These ligaments anchor the outer surface of the dura mater to the osteofibrous walls of the lumbar canal. They may form an irregular longitudinal septum partitioning the epidural space. Histologic examination demonstrated the fibroelastic composition of these ligaments and suggested their possible perivascular morphogenetic origin. CONCLUSION: The morphologic and topographic features of the meningovertebral ligaments explain the polygonal, stellar, or Y-shaped deformation of the dural sac observed on axial CT and MR images in patients with lumbar epidural lipomatosis.