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Many factors determine the optimal way to deliver a baby. A vertex presentation is the ideal situation for a vaginal birth, however, occiput posterior positions tend to proceed more slowly, often requiring an intervention in the form of forceps, vacuum extraction, or Cesarean section. In a large study, a majority of brow presentations were delivered by Cesarean section, however, because of 'postmaturity', factors other than labour dynamics may have played a role. Most face presentations can be delivered vaginally as long as the chin is anterior; there is no increase in fetal or maternal mortality. Mento-posterior positions cannot be delivered vaginally in most cases (unless rotated) and are candidates for Cesarean section in contemporary management.
Usually performing the Leopold maneuvers will demonstrate the presentation and possibly the position of the fetus. Ultrasound examination delivers the precise diagnosis and may indicate possible causes of a malpresentation. On vaginal examination, the leading part of the fetus becomes identifiable after the amniotic sac has been broken and the head is descending in the pelvis.
While a transverse lie prior to labor can be manually versed to a longitudinal lie, once the uterus starts contracting the uterus normally will not allow any version procedure. A shoulder presentation is an indication for a caesarean section. Generally, as it is diagnosed early, the baby is not damaged by the time of delivery. With the rupture of the membranes, there is an increased risk of a cord prolapse as the shoulder may not completely block the birth canal. Thus the caesarean section is ideally performed before the membranes break.
The delivery of the second twin in a transverse lie with a shoulder presentation represents a special situation that may be amenable to a vaginal delivery. As the first twin has just been delivered and the cervix is fully dilated the obstetrician may perform an internal version, that is inserting one hand into the uterus, find the baby’s feet, and then bring the baby into a breech position and deliver the baby as such.
When a baby is born bottom first there is more risk that the birth will not be straight forward and that the baby could be harmed. For example, when the baby's head passes through the mother’s pelvis the umbilical cord can be compressed which prevents delivery of oxygenated blood to the baby. Due to this and other risks, babies in breech position are usually born by a planned caesarean section in developed countries.
Caesarean section reduces the risk of harm or death for the baby but does increase risk of harm to the mother compared with a vaginal delivery. It is best if the baby is in a head down position so that they can be born vaginally with less risk of harm to both mother and baby. The next section is looking at External cephalic version or ECV which is a method that can help the baby turn from a breech position to a head down position.
Vaginal birth of a breech baby has its risks but caesarean sections are not always available or possible, a mother might arrive in hospital at a late stage of her labour or may choose not to have a caesarean section. In these cases, it is important that the clinical skills needed to deliver breech babies are not lost so that mothers and babies are as safe as possible. Compared with developed countries, planned caesarean sections have not produced as good results in developing countries - it is suggested that this is due to more breech vaginal deliveries being performed by experienced, skilled practitioners in these settings.
In twin pregnancies, it is very common for one or both babies to be in the breech position. Most often twin babies do not have the chance to turn around because they are born prematurely. If both babies are in the breech position and the mother has gone into labour early, a cesarean section may be the best option. About 30-40% of twin pregnancies result in only one baby being in the breech position. If this is the case, the babies can be born vaginally. After the first baby who is not in the breech position is delivered, the baby who is presented in the breech position may turn itself around, if this does not happen another procedure may performed called the breech extraction. The breech extraction is the procedure that involves the obstetrician grabbing the second twin's feet and pulling him/her into the birth canal. This will help with delivering the second twin vaginally. However, if the second twin is larger than the first, complications with delivering the second twin vaginally may arise and a cesarean section should be performed. At times, the first twin (the twin closest to the birth canal) can be in the breech position with the second twin being in the cephalic position (vertical). When this occurs, risks of complications are higher than normal. In particular, a serious complication known as Locked twins. This is when both babies interlock their chins during labour. When this happens a cesarean section should be performed immediately.
Management of shoulder dystocia has become a focus point for many obstetrical nursing units in North America. Courses such as the Canadian More-OB program encourage nursing units to do routine drills to prevent delays in delivery which adversely affect both mother and fetus. A common treatment mnemonic is ALARMER
- Ask for help. This involves preparing for the help of an obstetrician, for anesthesia, and for pediatrics for subsequent resuscitation of the infant that may be needed if the methods below fail.
- L hyperflexion (McRoberts' maneuver)
- Anterior shoulder disimpaction (pressure)
- Rubin maneuver
- M delivery of posterior arm
- Episiotomy
- Roll over on all fours
Typically the procedures are performed in the order listed above and the sequence ends whenever a technique is successful. Intentional clavicular fracture is a final attempt at nonoperative vaginal delivery prior to Zavanelli's maneuver or symphysiotomy, both of which are considered extraordinary treatment measures.
The most accurate method of diagnosis is prenatal screening through real-time fetal images. However, since maternal body habitus leads to diagnostic difficulties using this method, MRI and sonography are the most commonly used technique since there is no exposure to ionizing radiation. At the beginning of the second trimester, the central nervous system (CNS) and anatomic structures of the fetus can be clearly visualized and the characteristic malformations of iniencephaly, such as a shortened trunk, marked lordosis in the cervicothoracic vertebrae, absence or partial absence of the occipital squama, abnoramal fusion of vertebrae, closed vertebral arches, formation of an encephalocele (for iniencephaly apertus), and dorsiflexion of the head in respect to the spine, can be precisely diagnosed as well as the severity and location established. Once established, further decisions can be made with regard to terminating the pregnancy or providing a plan of adequate postnatal care.
Although the definition is imprecise, it occurs in approximately 0.3-1% of vaginal births.
Via a photo shown on a Facebook page, the mother of a child previously diagnosed with this condition recognised the symptoms and reported them to the family involved, resulting in an immediate diagnosis that medical professionals had overlooked in all earlier consultations.
Since many of the characteristics of iniencephaly, such as congenital retroflexion of the spine and fusion of the cervical vertebrae, are shared with other disorders, key differences are important to note.
While anencephaly experiences a partial to total lack of the neurocranium, iniencephaly does not. In anencephaly, the retroflexed head is not covered with skin while in iniencephaly, the retroflexed head is covered with skin entirely. Cervical vertebrae are malformed and reduced in iniencephaly while they are almost normal in anencephaly.
Even though KFS does experience malformed cervical vertebra due to failure of segmentation during early fetal development, there is not retroflexion of the head as seen in iniencephaly. While iniencephaly clausus is fatal, KFS is not and can be surgically corrected. Therefore, it is crucial to correctly diagnose KFS and not mistake it for iniencephaly clausus.
Diagnosis can be characterized by typical facial and cranial deformities.
Observatory signs of trigonocephaly are:
- a triangular shaped forehead seen from top view leading to a smaller anterior cranial fossa
- a visible and palpable midline ridge
- hypotelorism inducing ethmoidal hypoplasia
Imaging techniques (3D-CT, Röntgenography, MRI) show:
- epicanthal folds in limited cases
- teardrop shaped orbits angulated towards the midline of the forehead ('surprised coon' sign) in severe cases
- a contrast difference between a röntgenograph of a normal and a trigonocephalic skull
- anterior curving of the metopic suture seen from lateral view of the cranium on a röntgenograph
- a normal cephalic index (maximum cranium width / maximum cranium length) however, there is bitemporal shortening and biparietal broadening
The neuropsychological development is not always affected. These effects are only visible in a small percentage of children with trigonocephaly or other suture synostoses. Neuropsychological signs are:
- problems in behaviour, speech and language
- mental retardation
- neurodevelopmental delays such as ADHD (Attention Deficit Hyperactivity Disorder), ODD (Oppositional Defiant Disorder), ASD (Autism Spectrum Disorder) and CD (Conduct Disorder). Many of these delays become evident at school age.
This condition can be corrected by surgery if the child is young enough. The use of a cranial remolding orthosis can also benefit the child if the child begins wearing it at an early age.
Radiographic analysis by performing a computed axial tomographic scan is the gold standard for diagnosing craniosynostosis.
Plain radiography of the skull may be sufficient for diagnosing a single suture craniosynostosis and should therefore be performed, but the diagnostic value is outweighed by that of the CT-scan. Not only can the sutures be identified more accurately, thus objectively demonstrating a fused suture, but also evaluation of the brain for structural abnormalities and excluding other causes of asymmetric growth are possible at the same time. In addition to this, CT-scanning can visualize the extent of skull deformity, thereby enabling the surgeon to start planning surgical reconstruction.
If locked twins are diagnosed in early delivery, before either twin is born, both fetuses can be delivered by Caesarean section. If one fetus has been partially born, attempts can be made to disimpact the twins manually, such as by the Zavanelli maneuver, with a view to performing an assisted delivery with ventouse or forceps. If the diagnosis is made only after the first locked twin has died in the birth canal, or if it is not expected to survive, the first twin may be decapitated and its head pushed up to allow safe delivery of the second twin.
At least one case has been reported where hexoprenaline was used to relax the uterine smooth muscle and thereby temporarily inhibit labour so that the fetal heads could be disimpacted.
Since locked twins are often diagnosed in the late stages of delivery, it is often too late to intervene to save the life of the first twin and thus there is a high rate of stillbirth, estimated to be over 50%.
Brachycephaly can be corrected with a cranial remolding orthoses (helmet) which provide painless total contact over the prominent areas of the skull and leave voids over the flattened areas to provide a pathway for more symmetrical skull growth. Treatment generally takes 3–4 months, but varies depending on the infant's age and severity of the cranial asymmetry.
However studies by scientists in the Netherlands have found there was no significant difference over time between infants treated with helmets and infants left untreated. All parents of infants treated with helmets confirmed negative side effects including skin irritation and sweating.
This study focused only on patients with mild to moderate cases, the participation rate was only 21%, and there was a 73% reporting of fitting issues, calling into question the validity of the study. Incorrectly fit devices cannot be expected to yield results. Additionally, independent published research that examined the effectiveness of helmet therapy conclude that as many as 95% of
patients demonstrate an improvement in head shape symmetry following helmet therapy, and the American Orthotics and Prosthetics Association (AOPA) has serious concerns about the relevance and validity of this study.
There are several ways to classify craniosynostosis.
- For example, one can consider the number of closed sutures. If only one of the four sutures is prematurely closed (single suture craniosynostosis), the craniosynostosis is referred to as 'simple' (or 'isolated'). Whereas when two or more sutures are no longer open, the craniosynostosis is 'complex'.
- A second classification scheme gives a clinical description of the resulting shape of the skull. This will be further discussed under phenotype.
- A third classification involves the presence or absence of an identified craniofacial syndrome. Craniosynostosis where no extracranial deformations are present, is called non-syndromic or 'isolated' craniosynostosis. When there are extracranial deformations present, for instance involving the limbs, heart, central nervous system or the respiratory tract, you may speak of a syndromic form of craniosynostosis. More than 180 identified syndromes show deformations due to craniosynostosis. The following syndromes are associated with fibroblast growth factor receptors:
In addition, the following syndromes have been identified:
A Cochrane review concluded that "simple maternal hydration appears to increase amniotic fluid volume and may be beneficial in the management of oligohydramnios and prevention of oligohydramnios during labour or prior to external cephalic version."
In severe cases oligohydramnios may be treated with amnioinfusion during labor to prevent umbilical cord compression. There is uncertainty about the procedure's safety and efficacy, and it is recommended that it should only be performed in centres specialising in invasive fetal medicine and in the context of a multidisciplinary team.
In case of congenital lower urinary tract obstruction, fetal surgery seems to improve survival, according to a randomized yet small study.
Diagnosing colpocephaly prenatally is difficult because in many cases signs start to appear after birth. Prenatal diagnosis is made by detecting enlargement of either or both occipital horns of the lateral ventricles. Usually prenatal ultrasounds don't show cephalic abnormalities and in cases that they do show abnormality is of low accuracy, making it difficult to diagnose colpocephaly. Often, abnormalities in prenatal ultrasounds can be misdiagnosed as hydrocephalus.
Diagnosis may be delayed for several months because the infant's early behavior appears to be relatively normal. Transillumination, an examination in which light is passed through body tissues, can be used to diagnose hydranencephaly. An accurate, confirmed diagnosis is generally impossible until after birth, though prenatal diagnosis using fetal ultrasonography (ultrasound) can identify characteristic physical abnormalities that exist. Through thorough clinical evaluation, via physical findings, detailed patient history, and advanced imaging techniques, such as angiogram, computerized tomography (CT scan), magnetic resonance imaging (MRI), or more rarely transillumination after birth are the most accurate diagnostic techniques. However, diagnostic literature fails to provide a clear distinction between severe obstructive hydrocephalus and hydranencephaly, leaving some children with an unsettled diagnosis.
Preliminary diagnosis may be made in utero via standard ultrasound, and can be confirmed with a standard anatomy ultrasound. This sometimes proves to provide a misdiagnosis of differential diagnoses including bilaterally symmetric schizencephaly (a less destructive developmental process on the brain), severe hydrocephalus (cerebrospinal fluid excess within the skull), and alobar holoprosencephaly (a neurological developmental anomaly). Once destruction of the brain is complete, the cerebellum, midbrain, thalami, basal ganglia, choroid plexus, and portions of the occipital lobes typically remain preserved to varying degrees. Though the cerebral cortex is absent, in most cases the fetal head remains enlarged due to the continued production by the choroid plexus of cerebrospinal fluid that is inadequately reabsorbed causing increased intracranial pressure.
After birth, MR imaging can be done to look for cephalic abnormalities. This is the most commonly used method for diagnosing colpocephaly. Physicians look for abnormally large occipital horns of the lateral ventricles and diminished thickness of white matter. Spinal tapping is not a preferred method for diagnosis because newborn babies with colpocephaly or hydrocephaly have open fontanelles which makes it difficult to collect CSF. Also, colpocephaly is not associated with increased pressure.
Scaphocephaly is a type of cephalic disorder which occurs when there is a premature fusion of the sagittal suture. The sagittal suture joins together the two parietal bones of skull. Scaphocephaly is the most common of the craniosynostosis conditions and is characterized by a long, narrow head.
The term is from Greek "skaphe" meaning 'light boat or skiff' and "kephale" meaning 'head') describes a specific shape of a long narrow head that resembles an inverted boat.
Anencephaly can often be diagnosed before birth through an ultrasound examination. The maternal serum alpha-fetoprotein (AFP screening) and detailed fetal ultrasound can be useful for screening for neural tube defects such as spina bifida or anencephaly.
Simple surgical excision is curative. The recommended treatment is that the skin is peeled off the extra-auricular tissue and protruding cartilage remnants are trimmed. Normal appearance is achieved in majority of cases. The reconstruction successful in true cases of accessory auricle, as it also is in individuals with auricular appendages.