Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
Although most recognized for its correlation with the onset of glaucoma, the malformation is not limited to the eye, as Axenfeld syndrome when associated with the PITX2 genetic mutation usually presents congenital malformations of the face, teeth, and skeletal system.
The most characteristic feature affecting the eye is a distinct corneal posterior arcuate ring, known as an "embryotoxon". The iris is commonly adherent to the Schwalbe's line (posterior surface of the cornea).
Diagnosis
One of the three known genetic mutations which cause Rieger Syndrome can be identified through genetic samples analysis. About 40% of Axenfeld-Rieger sufferers have displayed mutations in genes PITX2, FOXC1, and PAX6. The difference between Type 1, 2, and 3 Axenfeld Syndrome is the genetic cause, all three types display the same symptoms and abnormalities.
The OMIM classification is as follows:
Detection of any of these mutations can give patients a clear diagnosis and prenatal procedures such as preimplantation genetic diagnosis, Chorionic villus sampling and Amniocentesis can be offered to patients and prospective parents.
While there is no cure for JBS, treatment and management of specific symptoms and features of the disorder are applied and can often be successful. Variability in the severity of JBS on a case-by-case basis determines the requirements and effectiveness of any treatment selected.
Pancreatic insufficiency and malabsorption can be managed with pancreatic enzyme replacement therapy, such as pancrelipase supplementation and other related methods.
Craniofacial and skeletal deformities may require surgical correction, using techniques including bone grafts and osteotomy procedures. Sensorineural hearing loss can be managed with the use of hearing aids and educational services designated for the hearing impaired.
Special education, specialized counseling methods and occupational therapy designed for those with mental retardation have proven to be effective, for both the patient and their families. This, too, is carefully considered for JBS patients.
MRI imaging can be used to detect whether the abducens nerve is present.
Since Duane-radial ray syndrome is a genetic disorder, a genetic test would be performed. One test that can be used is the SALL4 sequence analysis that is used to detect if SALL4 is present. If there is no pathogenic variant observed, a deletion/duplication analysis can be ordered following the SALL4 sequence analysis. As an alternative, another genetic test called a multi-gene panel can be ordered to detect SALL4 and any other genes of interest. The methods used for this panel vary depending on the laboratory.
Evaluation is in the form of a dye disappearance test followed by irrigation test. By using this sequence (with modifications) as a guide, the physician can frequently streamline diagnostic testing.
The dye disappearance test (DDT) is useful for assessing the presence or absence of adequate lacrimal outflow, especially in unilateral cases. It is more heavily relied upon in children, in whom lacrimal irrigation is impossible without deep sedation. Using a drop of sterile 2% fluorescein solution or a moistened fluorescein strip, the examiner instills fluorescein into the conjunctival fornices of each eye and then observes the tear film, preferably with the cobalt blue filter of the slit lamp. Persistence of significant dye and, particularly asymmetric clearance of the dye from the tear meniscus over a 5-minute period indicate an obstruction. If the DDT result is normal, severe lacrimal drainage dysfunction is highly unlikely. Variations of the DDT are the Jones tests.
Abdominal ultrasound is of some benefit, but not diagnostic. Features that suggest posterior urethral valves are bilateral hydronephrosis, a thickened bladder wall with thickened smooth muscle trabeculations, and bladder diverticula.
Voiding cystourethrogram (VCUG) is more specific for the diagnosis. Normal "plicae circularis" are variable in appearance and often not seen on normal VCUGs. PUV on voiding cystourethrogram is characterized by an abrupt tapering of urethral caliber near the verumontanum, with the specific level depending on the developmental variant. Vesicoureteral reflux is also seen in over 50% of cases. Very often the posterior urethra maybe dilated thus making the abrupt narrowing more obvious. the bladder wall may show trabeculations or sacculations or even diverticuli.
Diagnosis can also be made by cystoscopy, where a small camera is inserted into the urethra for direct visualization of the posteriorly positioned valve. A limitation of this technique is that posterior valve tissue is translucent and can be pushed against the wall of the urethra by inflowing irrigation fluid, making it difficult to visualize. Cystoscopy may also demonstrate the bladder changes.
Centers in Europe and Japan have also had excellent results with cystosonography, although it has not been approved for use in the United States yet.
When accompanied by the combination of situs inversus (reversal of the internal organs), chronic sinusitis, and bronchiectasis, it is known as Kartagener syndrome (only 50% of primary ciliary dyskinesia cases include situs inversus).
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.
Several diagnostic tests for this condition have been proposed. These include nasal nitric oxide levels, light microscopy of biopsies for ciliary beat pattern and frequency and electron microscopic examination of dynein arms. Genetic testing has also been proposed but this is difficult given that there are multiple genes involved.
It is possible to diagnose prenatally with amniocentesis, but it may not show a correct negative result. Amniocentesis can only diagnose anophthalmia when there is a chromosomal abnormality. Chromosomal abnormalities are only a minority of cases of anophthalmia.
Ultrasounds can be used to diagnose anophthalmia during gestation. Due to the resolution of the ultrasound, however, it is hard to diagnose it until the second trimester. The earliest to detect anophthalmia this way is approximately 20 weeks. 3D and 4D ultrasounds have proven to be more accurate at viewing the fetus's eyes during pregnancy and are another alternative to the standard ultrasound.
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.
It is named after the German ophthalmologist Theodor Axenfeld who studied anterior segment disorders, especially those such as Rieger Syndrome and the Axenfeld Anomaly.
Axenfeld-Rieger syndrome is characterized by abnormalities of the eyes, teeth, and facial structure. Rieger Syndrome, by medical definition, is determined by the presence of malformed teeth, underdeveloped anterior segment of the eyes, and cardiac problems associated with the Axenfeld anomaly. The term "Rieger syndrome" is sometimes used to indicate an association with glaucoma. Glaucoma occurs in up to 50% of patients with Rieger Syndrome. Glaucoma develops during adolescence or late-childhood, but often occurs in infancy. In addition, a prominent Schwalbe's line, an opaque ring around the cornea known as posterior embryotoxon, may arise with hypoplasia of the iris. Below average height and stature, stunted development of the mid-facial features and mental deficiencies may also be observed in patients.
Anterior segment mesenchymal dysgenesis is a failure of the normal development of the tissues of the anterior segment of the eye. It leads to anomalies in the structure of the mature anterior segment, associated with an increased risk of glaucoma and corneal opacity.
Peters' (frequently misspelled Peter's) anomaly is a specific type of mesenchymal anterior segment dysgenesis, in which there is central corneal leukoma, adhesions of the iris and cornea, and abnormalities of the posterior corneal stroma, Descemet's membrane, corneal endothelium, lens, and anterior chamber.
The most extensive epidemiological survey on this congenital malformation has been carried out by Dharmasena et al and using English National Hospital Episode Statistics, they calculated the annual incidence of anophthalmia, microphthalmia and congenital malformations of orbit/lacrimal apparatus from 1999 to 2011. According to this study the annual incidence of congenital microphthalmia in the United Kingdom was 10.8 (8.2 to 13.5) in 1999 and 10.0 (7.6 to 12.4) in 2011.
If suspected antenatally, a consultation with a paediatric surgeon/ paediatric urologist maybe indicated to evaluate the risk and consider treatment options.
Treatment is by endoscopic valve ablation. Fetal surgery is a high risk procedure reserved for cases with severe oligohydramnios, to try to limit the associated lung underdevelopment, or pulmonary hypoplasia, that is seen at birth in these patients. The risks of fetal surgery are significant and include limb entrapment, abdominal injury, and fetal or maternal death. Specific procedures for "in utero" intervention include infusions of amniotic fluid, serial bladder aspiration, and creating a connection between the amniotic sac and the fetal bladder, or vesicoamniotic shunt.
There are three specific endoscopic treatments of posterior urethral valves:
- Vesicostomy followed by valve ablation - a stoma, or hole, is made in the urinary bladder, also known as "low diversion", after which the valve is ablated and the stoma is closed.
- Pyelostomy followed by valve ablation - stoma is made in the pelvis of the kidney as a slightly "high diversion", after which the valve is ablated and the stoma is closed
- Primary (transurethral) valve ablation - the valve is removed through the urethra without creation of a stoma
The standard treatment is primary (transurethral) ablation of the valves. Urinary diversion is used in selected cases, and its benefit is disputed.
Following surgery, the follow-up in patients with posterior urethral valve syndrome is long term, and often requires a multidisciplinary effort between paediatric surgeons/ paediatric urologists, pulmonologists, neonatologists, radiologists and the family of the patient. Care must be taken to promote proper bladder compliance and renal function, as well as to monitor and treat the significant lung underdevelopment that can accompany the disorder. Definitive treatment may also be indicated for the vesico-ureteral reflux.
Lachiewicz–Sibley syndrome is a rare autosomal dominant disorder characterized by preauricular pits and renal disease. Persons with this disease may have hypoplasic kidneys or proteinuria. This disease was first described in a Caucasian family of British and Irish descent that emigrated to Ohio in the 19th century before settling in Nebraska. Many of the members of this family still live in Nebraska, although the relatives are now scattered throughout the country.
Unlike branchio-oto-renal (BOR) syndrome, Lachiewicz–Sibley syndrome is characterized by only preauricular pitting and renal disease. Persons with BOR syndrome also present with hearing loss, branchial fistulas or cysts, malformed ears, and lacrimal stenosis. Other anomalies in BOR syndrome may include a long narrow face, a deep overbite, and facial paralysis.
It was characterized in 1985.
In teratology, proboscis is a blind-ended, tubelike structure, commonly located in the midface.
Proboscis formation are classified in four general types: holoprosencephalic proboscis, lateral nasal proboscis, supernumerary proboscis, and disruptive proboscis.
- Holoprosencephalic proboscis is found in holoprosencephaly. In cyclopia or ethmocephaly, proboscis is an abnormally formed nose. In cyclopia, a single median eye is associated with arrhinia (absence of the nose) and usually with proboscis formation above the eye. In ethmocephaly, two separate hypoteloric eyes are associated with arrhinia and supraocular proboscis formation. In cebocephaly, no proboscis formation occurs, but a single-nostril nose is present.
- Lateral nasal proboscis (proboscis lateralis) is a tubular proboscis-like structure and represents incomplete formation of one side of the nose; it is found instead of a nostril. The olfactory bulb is usually rudimentary on the involved side. The lacrimal duct (tear duct), nasal bone, nasal cavity, vomer, maxillary sinus, cribriform plate, and ethmoid cells are often missing on the involved side. Ocular hypertelorism may be present. The proboscis lateralis is a rare nasal anomaly.
- Supernumerary proboscis (Accessory proboscis) is found when both nostrils are formed and a proboscis occurs additionally. Accessory proboscis arise from a supernumerary olfactory placode.
- Disruptive proboscis occur if an early embryonic hamartoneoplastic lesion arises in the primitive prosencephalon.
Surgery (orchiopexy) to retrieve the testes and position them in the scrotum is the primary treatment. Occasionally they are unsalvageable if located high in the retroperitoneum. During this surgery, the uterus is usually removed and attempts made to dissect away Müllerian tissue from the vas deferens and epididymis to improve the chance of fertility. If the person has male gender identity himself and the testes cannot be retrieved, testosterone replacement will be usually necessary at puberty should the affected individual choose to pursue medical attention. Lately, laparoscopic hysterectomy is offered to patients as a solution to both improve the chances of fertility and to prevent the occurrences of neoplastic tissue formation.
Anomalies resembling Pelger–Huët anomaly that are acquired rather than congenital have been described as pseudo Pelger–Huët anomaly. These can develop in the course of acute myelogenous leukemia or chronic myelogenous leukemia and in myelodysplastic syndrome. It has also been described in Filovirus disease.
In patients with these conditions, the pseudo–Pelger–Huët cells tend to appear late in the disease and often appear after considerable chemotherapy has been administered. The morphologic changes have also been described in myxedema associated with panhypopituitarism, vitamin B12 and folate deficiency, multiple myeloma, enteroviral infections, malaria, muscular dystrophy, leukemoid reaction secondary to metastases to the bone marrow, and drug sensitivity, sulfa and valproate toxicities are examples. In some of these conditions, especially the drug-induced cases, identifying the change as Pelger–Huët anomaly is important because it obviates the need for further unnecessary testing for cancer.
Peripheral blood smear shows a predominance of neutrophils with bilobed nuclei which are composed of two nuclear masses connected with a thin filament of chromatin. It resembles the pince-nez glasses, so it is often referred to as pince-nez appearance. Usually the congenital form is not associated with thrombocytopenia and leukopenia, so if these features are present more detailed search for myelodysplasia is warranted, as pseudo-Pelger–Huët anomaly can be an early feature of myelodysplasia.
A pelvic examination may reveal a double vagina or double cervix that should be further investigated and may lead to the discovery of a uterine septum. In most patients, however, the pelvic examination is normal. Investigations are usually prompted on the basis of reproductive problems.
Helpful techniques to investigate a septum are transvaginal ultrasonography and sonohysterography, MRI, and hysteroscopy. More recently 3-D ultrasonography has been advocated as an excellent non-invasive method to delineate the condition. Prior to modern imaging hysterosalpingography was used to help diagnose the uterine septum, however, a bicornuate uterus may deliver a similar image.
An important category of septate uterus is the hybrid type a variant that may be misdiagnosed as bicornuate uterus when seen by laparoscopy Professor El Saman From Egypt was the first to describe this anomaly and warned gynecologist about this common misdiagnosis, whenever there is a uterine fundus depression on laparoscopy gynecologists should compare the depth of this depression with the depth of the dividing internal interface. Hybrid septate uterus benefit from hysteroscopic metroplasty under laparoscopic control.
Treatment usually consists of observation unless the patient has concern, there is pain, drainage, or other symptoms related to the lesion. Surgical removal of the affected gland would be recommended in those cases. Another treatment option would be aspiration, which can be repeated multiple times. This is commonly performed in those who are debilitated or in those whose benefit from surgery would be outweighed by the risks. Prognosis is usually good; rarely this condition may devolve into lymphoma, or could actually represent 'occult' lymphoma from the outset.
Other forms of uterine malformation need to be considered in the work-up for uterine septum. An arcuate uterus contains a residual cranial septum that is smaller than an incomplete septum but definitions between the two conditions are not standardized, - a cause for discrepancies in the literature.
A bicornuate uterus is sometimes confused with a septate uterus as in each situation the cavity is partitioned, however, in the former case the uterine body is cranially doubled (two uterine horns) while in the latter a single uterine body is present. The former represents a malformation of incomplete fusion of the Müllerian systems, and the latter of incomplete absorption. A hysterosalpingogram may not be able to distinguish between the two conditions. The differentiation, however, is important as a septum can be corrected by hysteroscopy, while a bicornuate uterus would be corrected by a metroplasty via laparotomy if necessary.
Although the finding itself is rare, MGDA can be associated with midline cranial defects and abnormal carotid circulation, such as carotid stenosis/aplasia or progressive vascular obstruction with collateralization (also known as moyamoya disease). The vascular defects may lead to ischemia, stroke, or seizures and so a finding of MGDA should be further investigated with radiographic imaging.