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Phototherapeutic keratectomy (PTK) done by an ophthalmologist can restore and preserve useful visual function for a significant period of time in patients with anterior corneal dystrophies including EBMD.
Patients may complain of severe problems with dry eyes, or with visual obscurations. It can also be asymptomatic, and only discovered because of subtle lines and marks seen during an eye exam.
EBMD is a bilateral anterior corneal dystrophy characterized by grayish epithelial fingerprint lines, geographic map-like lines, and dots (or microcysts) on slit-lamp examination. Findings are variable and can change with time. While the disorder is usually asymptomatic, up to 10% of patients may have recurrent corneal erosions, usually beginning after age 30; conversely, 50% of patients presenting with idiopathic recurrent erosions have evidence of this dystrophy.
Diagnosis can be established on clinical grounds and this may be enhanced with studies on surgically excised corneal tissue and in some cases with molecular genetic analyses. As clinical manifestations widely vary with the different entities, corneal dystrophies should be suspected when corneal transparency is lost or corneal opacities occur spontaneously, particularly in both corneas, and especially in the presence of a positive family history or in the offspring of consanguineous parents.
Superficial corneal dystrophies - "Meesmann dystrophy" is characterized by distinct tiny bubble-like, punctate opacities that form in the central corneal epithelium and to a lesser extent in the peripheral cornea of both eyes during infancy that persists throughout life. Symmetrical reticular opacities form in the superficial central cornea of both eyes at about 4–5 years of age in "Reis-Bücklers corneal dystrophy". Patient remains asymptomatic until epithelial erosions precipitate acute episodes of ocular hyperemia, pain, and photophobia. Visual acuity eventually becomes reduced during the second and third decades of life following a progressive superficial haze and an irregular corneal surface. In "Thiel–Behnke dystrophy", sub-epithelial corneal opacities form a honeycomb-shaped pattern in the superficial cornea. Multiple prominent gelatinous mulberry-shaped nodules form beneath the corneal epithelium during the first decade of life in "Gelatinous drop-like corneal dystrophy" which cause photophobia, tearing, corneal foreign body sensation and severe progressive loss of vision. "Lisch epithelial corneal dystrophy" is characterized by feather shaped opacities and microcysts in the corneal epithelium that are arranged in a band-shaped and sometimes whorled pattern. Painless blurred vision sometimes begins after sixty years of life.
Corneal stromal dystrophies - "Macular corneal dystrophy" is manifested by a progressive dense cloudiness of the entire corneal stroma that usually first appears during adolescence and eventually causing severe visual impairment. In "Granular corneal dystrophy" multiple small white discrete irregular spots that resemble bread crumbs or snowflakes become apparent beneath Bowman zone in the superficial central corneal stroma. They initially appear within the first decade of life. Visual acuity is more or less normal. "Lattice dystrophy" starts as fine branching linear opacities in Bowman's layer in the central area and spreads to the preiphery. Recurrent corneal erosions may occur. The hallmark of "Schnyder corneal dystrophy" is the accumulation of crystals within the corneal stroma which cause corneal clouding typically in a ring-shaped fashion.
Posterior corneal dystrophies - "Fuchs corneal dystrophy" presents during the fifth or sixth decade of life. The characteristic clinical findings are excrescences on a thickened Descemet membrane (cornea guttae), generalized corneal edema and decreased visual acuity. In advanced cases, abnormalities are found in the all layers of the cornea. In "posterior polymorphous corneal dystrophy" small vesicles appear at the level of Descemet membrane. Most patients remain asymptomatic and corneal edema is usually absent. "Congenital hereditary endothelial corneal dystrophy" is characterized by a diffuse ground-glass appearance of both corneas and markedly thickened (2–3 times thicker than normal) corneas from birth or infancy.
Early stages may be asymptomatic and may not require any intervention. Initial treatment may include hypertonic eyedrops and ointment to reduce the corneal edema and may offer symptomatic improvement prior to surgical intervention.
Suboptimal vision caused by corneal dystrophy usually requires surgical intervention in the form of corneal transplantation. Penetrating keratoplasty, a common type of corneal transplantation, is commonly performed for extensive corneal dystrophy.
With penetrating keratoplasty (corneal transplant), the long-term results are good to excellent. Recent surgical improvements have been made which have increased the success rate for this procedure. However, recurrence of the disease in the donor graft may happen. Superficial corneal dystrophies do not need a penetrating keratoplasty as the deeper corneal tissue is unaffected, therefore a lamellar keratoplasty may be used instead.
Phototherapeutic keratectomy (PTK) can be used to excise or ablate the abnormal corneal tissue. Patients with superficial corneal opacities are suitable candidates for a this procedure.
The center of the cornea shows normal thickness, with an intact central epithelium, but the inferior cornea exhibits a peripheral band of thinning, to about 1–2 mm. The portion of the cornea that is immediately adjacent to the limbus is spared, usually a strip of about 1–2 mm. In PMD we can see high against the rule astigmatism along with horizontal bow ties. The inferior peripheral thinning is seen between the 4 o'clock and 8 o'clock positions.
PMD lacks apical corneal scarring, Rizutti's phenomenon, Munson's sign, and the central corneal thickness is usually normal.
The gold standard diagnostic test for PMD is corneal topography. However, it may not as specific as corneal pachymetry, because corneal topography only evaluates the degree and distribution of surface irregularities on the cornea, not the thickness of the cornea. Corneal topography may show a "crab claw-like" appearance, a finding that is seen in both keratoconus and in pellucid marginal degeneration. Thus, if corneal topography is used for diagnosis, it should be in conjunction with clinical findings of peripheral, inferior corneal thinning.
The incidence and prevalence of PMD are unknown, and no studies have yet investigated its prevalence or incidence. However, it is generally agreed that PMD is a very rare condition. Some uncertainty regarding the incidence of PMD may be attributed to its confusion with keratoconus. PMD is not linked to race or age, although most cases present early in life, between 20 and 40 years of age. While PMD is usually considered to affect men and women equally, some studies suggest that it may affect men more frequently.
Several diseases have been observed in patients with PMD. However, no causal relationships have been established between any of the associated diseases and the pathogenesis of PMD. Such diseases include: chronic open-angle glaucoma, retinitis pigmentosa, retinal lattice degeneration, scleroderma, kerato-conjunctivitis, eczema, and hyperthyroidism.
Lisch epithelial corneal dystrophy (LECD), also known as band-shaped and whorled microcystic dystrophy of the corneal epithelium, is a rare form of corneal dystrophy first described in 1992 by Lisch et al. In one study it was linked to chromosomal region Xp22.3, with as yet unknown candidate genes.
The main features of this disease are bilateral or unilateral gray band-shaped and feathery opacities. They sometimes take on a form of a whirlpool, repeating the known pattern of corneal epithelium renewal. Abrasion of the epithelium in 3 patients brought only temporary relief, with abnormal epithelium regrowth in several months.
Epithelial cells in the zones of opacity were shown to have diffuse cytoplasmic vacuoles with as yet unestablished content.
Band keratopathy is a corneal disease derived from the appearance of calcium on the central cornea. This is an example of metastatic calcification, which by definition, occurs in the presence of hypercalcemia.
Band keratopathy is seen when there is calcification of the epithelial basement membrane, Bowman's membrane, and the anterior stroma with destruction of Bowman's membrane. The calcium salts are intracellular when the process is due to alteration of systemic calcium metabolism, whereas they are extracellular when due to local disease.
Cases of lymphangioma are diagnosed by histopathologic inspection. In prenatal cases, cystic lymphangioma is diagnosed using an ultrasound; when confirmed amniocentesis may be recommended to check for associated genetic disorders.
Oculocutaneous Albinism Type I or –Type 1A (OCA1A) is an autosomal recessive skin disease associated with albinism. This type of albinism is caused when the gene OCA1 does not function properly.
The location of OCA1 may be written as "11q1.4-q2.1", meaning it is on chromosome 11, long arm, somewhere in the range of band 1, sub-band 4, and band 2, sub-band 1.
Amniotic band syndrome is considered an accidental event and it does not appear to be genetic or hereditary, so the likelihood of it occurring in another pregnancy is remote. The cause of amnion tearing is unknown and as such there are no known preventative measures.
Amniotic band syndrome is often difficult to detect before birth as the individual strands are small and hard to see on ultrasound. Often the bands are detected indirectly because of the constrictions and swelling upon limbs, digits, etc. Misdiagnosis is also common, so if there are any signs of amniotic bands, further detailed ultrasound tests should be done to assess the severity. 3D ultrasound and MRI can be used for more detailed and accurate diagnosis of bands and the resulting damage/danger to the fetus.
The prognosis for lymphangioma circumscriptum and cavernous lymphangioma is generally excellent. This condition is associated with minor bleeding, recurrent cellulitis, and lymph fluid leakage. Two cases of lymphangiosarcoma arising from lymphangioma circumscriptum have been reported; however, in both of the patients, the preexisting lesion was exposed to extensive radiation therapy.
In cystic hygroma, large cysts can cause dysphagia, respiratory problems, and serious infection if they involve the neck. Patients with cystic hygroma should receive cytogenetic analysis to determine if they have chromosomal abnormalities, and parents should receive genetic counseling because this condition can recur in subsequent pregnancies.
Complications after surgical removal of cystic hygroma include damage to the structures in the neck, infection, and return of the cystic hygroma.
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.
Lymphatic malformations may be detected in the human fetus by ultrasound if they are of sufficient size. Detection of a cystic malformation may prompt further investigation, such as amniocentesis, in order to evaluate for genetic abnormalities in the fetus. Lymphatic malformations may be discovered postnatally or in older children/adults, and most commonly present as a mass or as an incidental finding during medical imaging.
Verification of the diagnosis may require more testing, as there are multiple cystic masses that arise in children. Imaging, such as ultrasound or MRI, may provide more information as to the size and extent of the lesion.
CPAMs are often identified during routine prenatal ultrasonography. Identifying characteristics on the sonogram include: an echogenic (bright) mass appearing in the chest of the fetus, displacement of the heart from its normal position, a flat or everted (pushed downward) diaphragm, or the absence of visible lung tissue.
CPAMs are classified into three different types based largely on their gross appearance. Type I has a large (>2 cm) multiloculated cysts. Type II has smaller uniform cysts. Type III is not grossly cystic, referred to as the "adenomatoid" type. Microscopically, the lesions are not true cysts, but communicate with the surrounding parenchyma. Some lesions have an abnormal connection to a blood vessel from an aorta and are referred to as "hybrid lesions."
Microcystic lymphatic malformations are a cutaneous condition characterized by aggregations of ill-defined, abnormal, microscopic lymphatic channels.
13q deletion syndrome can only be definitively diagnosed by genetic analysis, which can be done prenatally or after birth. Increased nuchal translucency in a first-trimester ultrasound may indicate the presence of 13q deletion.
The earliest point at which a CPAM can be detected is by prenatal ultrasound. The classic description is of an echogenic lung mass that gradually disappears over subsequent ultrasounds. The disappearance is due to the malformation becoming filled with fluid over the course of the gestation, allowing the ultrasound waves to penetrate it more easily and rendering it invisible on sonographic imaging. When a CPAM is rapidly growing, either solid or with a dominant cyst, they have a higher incidence of developing venous outflow obstruction, cardiac failure and ultimately "hydrops fetalis". If "hydrops" is not present, the fetus has a 95% chance of survival. When hydrops is present, risk of fetal demise is much greater without "in utero" surgery to correct the pathophysiology. The greatest period of growth is during the end of the second trimester, between 20–26 weeks.
A measure of mass volume divided by head circumference, termed cystic adenomatoid malformation volume ratio (CVR) has been developed to predict the risk of "hydrops". The lung mass volume is determined using the formula (length × width × anteroposterior diameter ÷ 2), divided by head circumference. With a CVR greater than 1.6 being considered high risk. Fetuses with a CVR less than 1.6 and without a dominant cyst have less than a 3% risk of hydrops. After delivery, if the patient is symptomatic, resection is mandated. If the infant is asymptomatic, the need for resection is a subject of debate, though it is usually recommended. Development of recurrent infections, rhabdomyosarcoma, adenocarcinomas "in situ" within the lung malformation have been reported.
Surgical correction is recommended when a constriction ring results in a limb contour deformity, with or without lymphedema.
Serous cystic neoplasms can come to clinical attention in a variety of ways. The most common symptoms are very non-specific and include abdominal pain, nausea and vomiting. In contrast to many of the other tumors of the pancreas, patients rarely develop jaundice (a yellowing of the skin and eyes caused by obstruction of the bile duct), or weight loss. These signs and symptoms are not specific for a serous cystic neoplasm, making it more difficult to establish a diagnosis. Doctors will therefore often order additional tests.
Once a doctor has reason to believe that a patient may have serous cystic neoplasm, he or she can confirm that suspicion using one of a number of imaging techniques. These include computerized tomography (CT), endoscopic ultrasound (EUS), and magnetic resonance cholangiopancreatography (MRCP). These tests will reveal a cystic mass within the pancreas. The cysts do not communicate with the larger pancreatic ducts. In some cases a fine needle aspiration (FNA) biopsy can be obtained to confirm the diagnosis. Fine needle aspiration biopsy can be performed through an endoscope at the time of endoscopic ultrasound, or it can be performed through the skin using a needle guided by ultrasound or CT scanning.
A growing number of patients are now being diagnosed before they develop symptoms (asymptomatic patients). In these cases, the lesion in the pancreas is discovered accidentally (by chance) when the patient is being scanned (x-rayed) for another reason.
A baby with a prenatally diagnosed cystic hygroma should be delivered in a major medical center equipped to deal with neonatal complications, such as a neonatal intensive care unit. An obstetrician usually decides the method of delivery. If the cystic hygroma is large, a cesarean section may be performed. After birth, infants with a persistent cystic hygroma must be monitored for airway obstruction. A thin needle may be used to reduce the volume of the cystic hygroma to prevent facial deformities and airway obstruction. Close observation of the baby by a neonatologist after birth is recommended. If resolution of the cystic hygroma does not occur before birth, a pediatric surgeon should be consulted.
Cystic hygromas that develop in the third trimester, after thirty weeks gestation, or in the postnatal period are usually not associated with chromosome abnormalities. There is a chance of recurrence after surgical removal of the cystic hygroma. The chance of recurrence depends on the extent of the cystic hygroma and whether its wall was able to be completely removed.
Treatments for removal of cystic hygroma are surgery or sclerosing agents which include:
- Bleomycin
- Doxycycline
- Ethanol (pure)
- Picibanil (OK-432)
- Sodium tetradecyl sulfate
The diagnosis of constriction ring syndrome can be confirmed with an ultrasonography. The clinical manifestations can be extremely variable. It could be a single or multiple manifestation. This can be confirmed at the end of the first trimester or at the beginning of the second trimester. But not every patient will be diagnosed at that moment, most will get this diagnosis at birth.
It can occur in a number of situations which include:
- Amniotic band syndrome : particularly if unilateral
- Cornelia de Lange Syndrome
- Fetal hydantoin syndrome
- Incontinentia pigmenti