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The type of treatment needed for dogs diagnosed with CM/SM depends on the severity of the condition and the age of the dog. Young dogs with clinical signs should be considered for surgical removal to minimize the progression of the disease as the dog ages. Older dogs with little or no clinical signs may be treated medically, rather than surgically. However, severe cases of CM/SM may require surgery regardless of age. The goal of surgery is syrynx decompression through restoration of normal cerebrospinal fluid circulation.
The surgical treatment of CM in dogs is described as "foramen magnum decompression FMD". Despite an approximately 80% success rate with this surgical technique, there is a 25% to 50% relapse, primarily due to excessive scar tissue formation at the decompression site. A cranioplasty may be performed instead, in which a plate, constructed using titanium mesh and bone cement, is fixed to the back of the skull following a standard FMD procedure. The procedure had been effective in humans. The postoperative relapse rate associated with the titanium cranioplasty procedure is less than 7%.
While there is no current cure, the treatments for Chiari malformation are surgery and management of symptoms, based on the occurrence of clinical symptoms rather than the radiological findings. The presence of a syrinx is known to give specific signs and symptoms that vary from dysesthetic sensations to algothermal dissociation to spasticity and paresis. These are important indications that decompressive surgery is needed for patients with Chiari Malformation Type II. Type II patients have severe brain stem damage and rapidly diminishing neurological response.
Decompressive surgery involves removing the lamina of the first and sometimes the second or third cervical vertebrae and part of the occipital bone of the skull to relieve pressure. The flow of spinal fluid may be augmented by a shunt. Since this surgery usually involves the opening of the dura mater and the expansion of the space beneath, a dural graft is usually applied to cover the expanded posterior fossa.
A small number of neurological surgeons believe that detethering the spinal cord as an alternate approach relieves the compression of the brain against the skull opening (foramen magnum), obviating the need for decompression surgery and associated trauma. However, this approach is significantly less documented in the medical literature, with reports on only a handful of patients. It should be noted that the alternative spinal surgery is also not without risk.
Complications of decompression surgery can arise. They include bleeding, damage to structures in the brain and spinal canal, meningitis, CSF fistulas, occipito-cervical instability and pseudomeningeocele. Rare post-operative complications include hydrocephalus and brain stem compression by retroflexion of odontoid. Also, an extended CVD created by a wide opening and big duroplasty can cause a cerebellar "slump". This complication needs to be corrected by cranioplasty.
In certain cases, irreducible compression of the brainstem occurs from in front (anteriorly or ventral) resulting in a smaller posterior fossa and associated Chiari malformation. In these cases, an anterior decompression is required. The most commonly used approach is to operate through the mouth (transoral) to remove the bone compressing the brainstem, typically the odontoid. This results in decompressing the brainstem and therefore gives more room for the cerebellum, thus decompressing the Chiari malformation. Arnold Menzes, MD, is the neurosurgeon who pioneered this approach in the 1970s at the University of Iowa. Between 1984 and 2008 (the MR imaging era), 298 patients with irreducible ventral compression of the brainstem and Chiari type 1 malformation underwent a transoral approach for ventral cervicomedullary decompression at the University of Iowa. The results have been excellent resulting in improved brainstem function and resolution of the Chiari malformation in the majority of patients.
Surgery is not always recommended for syringomyelia patients. For many patients, the main treatment is analgesia. Physicians specializing in pain management can develop a medication and treatment plan to ameliorate pain. Medications to combat any neuropathic pain symptoms such as shooting and stabbing pains (e.g. gabapentin or pregabalin) would be first-line choices. Opiates are usually prescribed for pain for management of this condition. Facet injections are not indicated for treatment of syringomyelia.
Drugs have no curative value as a treatment for syringomyelia. Radiation is used rarely and is of little benefit except in the presence of a tumor. In these cases, it can halt the extension of a cavity and may help to alleviate pain.
In the absence of symptoms, syringomyelia is usually not treated. In addition, a physician may recommend not treating the condition in patients of advanced age or in cases where there is no progression of symptoms. Whether treated or not, many patients will be told to avoid activities that involve straining.
Since the natural history of syringomyelia is poorly understood, a conservative approach may be recommended. When surgery is not yet advised, patients should be carefully monitored. Periodic MRI's and physical evaluations should be scheduled at the recommendation of a qualified physician.
Surgery
Surgical intervention is warranted in patients who present with new onset neurological signs and symptoms or have a history of progressive neurological manifestations which can be related to this abnormality. The surgical procedure required for the effective treatment of diastematomyelia includes decompression (surgery) of neural elements and removal of bony spur. This may be accomplished with or without resection and repair of the duplicated dural sacs. Resection and repair of the duplicated dural sacs is preferred since the dural abnormality may partly contribute to the "tethering" process responsible for the symptoms of this condition.
Post-myelographic CT scanning provides individualized detailed maps that enable surgical treatment of cervical diastematomyelia, first performed in 1983.
Observation
Asymptomatic patients do not require surgical treatment. These patients should have regular neurological examinations since it is known that the condition can deteriorate. If any progression is identified, then a resection should be performed.
Treatment for brain AVMs can be symptomatic, and patients should be followed by a neurologist for any seizures, headaches, or focal neurologic deficits. AVM-specific treatment may also involve endovascular embolization, neurosurgery or radiosurgery.
Embolization, that is, cutting off the blood supply to the AVM with coils, particles, acrylates, or polymers introduced by a radiographically guided catheter, may be used in addition to neurosurgery or radiosurgery, but is rarely successful in isolation except in smaller AVMs. Gamma knife may also be used.
The first step after diagnosis is finding a neurosurgeon who is experienced in the treatment of syringomyelia. Surgery is the treatment for syringomyelia. Evaluation of the condition is necessary because syringomyelia can remain stationary for long periods of time, and in some cases progress rapidly.
Surgery of the spinal cord has certain characteristic risks associated with it, and the benefits of a surgical procedure on the spine have to be weighed against the possible complications associated with any procedure. Surgical treatment is aimed at correcting the condition that allowed the syrinx to form. It is vital to bear in mind that the drainage of a syrinx does not necessarily mean the elimination of the syrinx-related symptoms but rather is aimed at stopping progression. In cases involving an Arnold-Chiari malformation, the main goal of surgery is to provide more space for the cerebellum at the base of the skull and upper cervical spine without entering the brain or spinal cord. This often results in flattening or disappearance of the primary syrinx or cavity, over time, as the normal flow of cerebrospinal fluid is restored. If a tumor is causing syringomyelia, removal of the tumor is the treatment of choice, if this is considered to be safe.
Surgery results in stabilization or modest improvement in symptoms for most patients. Delay in treatment may result in irreversible spinal cord injury. Recurrence of syringomyelia after surgery may make additional operations necessary; these may not be completely successful over the long term.
In some patients it may also be necessary to drain the syrinx, which can be accomplished using a catheter, drainage tubes, and valves. This system is also known as a shunt. Shunts are used in both the communicating and noncommunicating forms of the disorder. First, the surgeon must locate the syrinx. Then, the shunt is placed into it with the other end draining cerebrospinal fluid (CSF) into a cavity, usually the abdomen. This type of shunt is called a ventriculoperitoneal shunt and is particularly useful in cases involving hydrocephalus. By draining syrinx fluid, a shunt can arrest the progression of symptoms and relieve pain, headache, and tightness. Syringomyelia shunts are not always successful and can become blocked as with other central nervous system shunts.
The decision to use a shunt requires extensive discussion between doctor and patient, as this procedure carries with it greater risk of injury to the spinal cord, infection, blockage, or hemorrhage and may not necessarily work for all patients. Draining the syrinx more quickly does not produce better outcomes, but a shunt may be required if the fluid in the syrinx is otherwise unable to drain.
In the case of trauma-related syringomyelia, the surgeon operates at the level of the initial injury. The syrinx collapses at surgery, but a tube or shunt is usually necessary to prevent re-expansion.
One approach used for treatment is embolization. A six-vessel angiogram is employed to determine the vascular supply to the fistula. Detachable coils, liquid embolic agents like NBCA, and onyx, or combinations of both are injected into the blood vessel to occlude the DAVF. Preoperative embolization can also be used to supplement surgery.
DAVFs are also managed surgically. The operative approach varies depending on the location of the lesion.
Stereotactic radiosurgery
Stereotactic radiosurgery is used obliterating DAVFs post-embolization, and is considered an important adjunct. Use of this method, however, is limited to benign DAVFs that have failed other treatments.
There is no cure for this condition. Treatment is supportive and varies depending on how symptoms present and their severity. Some degree of developmental delay is expected in almost all cases of M-CM, so evaluation for early intervention or special education programs is appropriate. Rare cases have been reported with no discernible delay in academic or school abilities.
Physical therapy and orthopedic bracing can help young children with gross motor development. Occupational therapy or speech therapy may also assist with developmental delays. Attention from an orthopedic surgeon may be required for leg length discrepancy due to hemihyperplasia.
Children with hemihyperplasia are thought to have an elevated risk for certain types of cancers. Recently published management guidelines recommend regular abdominal ultrasounds up to age eight to detect Wilms' tumor. AFP testing to detect liver cancer is not recommended as there have been no reported cases of hepatoblastoma in M-CM patients.
Congenital abnormalities in the brain and progressive brain overgrowth can result in a variety of neurological problems that may require intervention. These include hydrocephalus, cerebellar tonsillar herniation (Chiari I), seizures and syringomyelia. These complications are not usually congenital, they develop over time often presenting complications in late infancy or early childhood, though they can become problems even later. Baseline brain and spinal cord MRI imaging with repeat scans at regular intervals is often prescribed to monitor the changes that result from progressive brain overgrowth.
Assessment of cardiac health with echocardiogram and EKG may be prescribed and arrhythmias or abnormalities may require surgical treatment.
Treatments of NTDs depends on the severity of the complication. No treatment is available for anencephaly and infants usually do not survive more than a few hours. Aggressive surgical management has improved survival and the functions of infants with spina bifida, meningoceles and mild myelomeningoceles. The success of surgery often depends on the amount of brain tissue involved in the encephalocele. The goal of treatment for NTDs is to allow the individual to achieve the highest level of function and independence. Fetal surgery in utero before 26 weeks gestation has been performed with some hope that there is benefit to the final outcome including a reduction in Arnold–Chiari malformation and thereby decreases the need for a ventriculoperitoneal shunt but the procedure is very high risk for both mother and baby and is considered extremely invasive with questions that the positive outcomes may be due to ascertainment bias and not true benefit. Further, this surgery is not a cure for all problems associated with a neural tube defect. Other areas of research include tissue engineering and stem cell therapy but this research has not been used in humans.
Benign tumors may not require treatment but may need to be monitored for any change in the growth. Growth of the tumors in the nose, lips, or eyelids can be treated with steroid drugs to slow its progress. Steroids can be taken orally or injected directly into the tumor. Applying pressure to the tumor can also be used to minimize swelling at the site of the hemangioma. A procedure that uses small particles to close off the blood supply is known as sclerotherapy. This allows for tumor shrinkage and less pain. It is possible for the tumor to regrow its blood supply after the procedure has been done. If the lesion caused by the cavernous hemangioma is destroying healthy tissue around it or if the patient is experiencing major symptoms, then surgery can be used to remove the tumor piecemeal. A common complication of the surgery is hemorrhage and the loss of blood. There is also the possibility of the hemangioma reoccurring after its removal. Additionally, the risk of a stroke or death is also possible.
Treatment for those with lissencephaly is symptomatic and depends on the severity and locations of the brain malformations. Supportive care may be needed to help with comfort and nursing needs. Seizures may be controlled with medication and hydrocephalus may require shunting. If feeding becomes difficult, a gastrostomy tube may be considered.
Standard treatment is after delivery. There is tentative evidence about treatment for severe disease before delivery while the baby is inside the womb. As of 2014 the evidence; however, remains insufficient to determine benefits and harms.
Treatment of spina bifida during pregnancy is not without risk. To the mother, this includes scarring of the uterus. To the baby, there is the risk of preterm birth.
Broadly, there are two forms of prenatal treatment. The first is open fetal surgery, where the uterus is opened and the spina bifida repair performed. The second is via fetoscopy. These techniques may be an option to standard therapy.
Treatment for Sturge–Weber syndrome is symptomatic. Laser treatment may be used to lighten or remove the birthmark. Anticonvulsant medications may be used to control seizures. Doctors recommend early monitoring for glaucoma, and surgery may be performed on more serious cases. When one side of the brain is affected and anticonvulsants prove ineffective, the standard treatment is neurosurgery to remove or disconnect the affected part of the brain (hemispherectomy). Physical therapy should be considered for infants and children with muscle weakness. Educational therapy is often prescribed for those with mental retardation or developmental delays, but there is no complete treatment for the delays.
Brain surgery involving removing the portion of the brain that is affected by the disorder can be successful in controlling the seizures so that the patient has only a few seizures that are much less intense than pre-surgery. Surgeons may also opt to "switch-off" the affected side of the brain.
Latanoprost (Xalatan), a prostaglandin, may significantly reduce IOP (intraocular pressure) in patients with glaucoma associated with Sturge–Weber syndrome. Latanoprost is commercially formulated as an aqueous solution in a concentration of 0.005% preserved with 0.02% benzalkonium chloride (BAC). The recommended dosage of latanoprost is one drop daily in the evening, which permits better diurnal IOP control than does morning instillation. Its effect is independent of race, gender or age, and it has few to no side effects. Contraindications include a history of CME, epiretinal membrane formation, vitreous loss during cataract surgery, history of macular edema associated with branch retinal vein occlusion, history of anterior uveitis, and diabetes mellitus. It is also wise to advise patients that unilateral treatment can result in heterochromia or hypertrichosis that may become cosmetically objectionable.
Examples of possible complications include shunt malfunction, shunt failure, and shunt infection, along with infection of the shunt tract following surgery (the most common reason for shunt failure is infection of the shunt tract). Although a shunt generally works well, it may stop working if it disconnects, becomes blocked (clogged), infected, or it is outgrown. If this happens the cerebrospinal fluid will begin to accumulate again and a number of physical symptoms will develop (headaches, nausea, vomiting, photophobia/light sensitivity), some extremely serious, like seizures. The shunt failure rate is also relatively high (of the 40,000 surgeries performed annually to treat hydrocephalus, only 30% are a patient's first surgery) and it is not uncommon for patients to have multiple shunt revisions within their lifetime.
Another complication can occur when CSF drains more rapidly than it is produced by the choroid plexus, causing symptoms - listlessness, severe headaches, irritability, light sensitivity, auditory hyperesthesia (sound sensitivity), nausea, vomiting, dizziness, vertigo, migraines, seizures, a change in personality, weakness in the arms or legs, strabismus, and double vision - to appear when the patient is vertical. If the patient lies down, the symptoms usually vanish quickly. A CT scan may or may not show any change in ventricle size, particularly if the patient has a history of slit-like ventricles. Difficulty in diagnosing overdrainage can make treatment of this complication particularly frustrating for patients and their families. Resistance to traditional analgesic pharmacological therapy may also be a sign of shunt overdrainage "or" failure.
The diagnosis of cerebrospinal fluid buildup is complex and requires specialist expertise. Diagnosis of the particular complication usually depends on when the symptoms appear - that is, whether symptoms occur when the patient is upright or in a prone position, with the head at roughly the same level as the feet.
In most cases, a fetus with CPAM is closely monitored during pregnancy and the CPAM is removed via surgery after birth. Most babies with a CPAM are born without complication and are monitored during the first few months. Many patients have surgery, typically before their first birthday, because of the risk of recurrent lung infections associated with CPAMs. Some pediatric surgeons can safely remove these lesions using very tiny incisions using minimally invasive surgical techniques (thoracoscopy). However, some CPAM patients live a full life without any complication or incident. It is hypothesized that there are thousands of people living with an undetected CPAM. Through ultrasound testing employed in recent years, many more patients are aware that they live with this condition. Rarely, long standing CPAMs have been reported to become cancerous.
Very large cystic masses might pose a danger during birth because of the airway compression. In this situation, a special surgical type of delivery called the EXIT procedure may be used.
In rare extreme cases, where fetus's heart is in danger, fetal surgery can be performed to remove the CPAM. If non-immune hydrops fetalis develop, there is a near universal mortality of the fetus without intervention. Fetal surgery can improve the chances of survival to 50-60%. Recently, several studies found that a single course of prenatal steroids (betamethasone) may increase survival in hydropic fetuses with microcystic CPAMs to 75-100%. These studies indicate that large microcystic lesions may be treated prenatally without surgical intervention. Large macrocyst lesions may require in utero placement of a Harrison thoracoamniotic shunt.
Most individuals with myelomeningocele will need periodic evaluations by a variety of specialists:
- Physiatrists coordinate the rehabilitation efforts of different therapists and prescribe specific therapies, adaptive equipment, or medications to encourage as high of a functional performance within the community as possible.
- Orthopedists monitor growth and development of bones, muscles, and joints.
- Neurosurgeons perform surgeries at birth and manage complications associated with tethered cord and hydrocephalus.
- Neurologists treat and evaluate nervous system issues, such as seizure disorders.
- Urologists to address kidney, bladder, and bowel dysfunction – many will need to manage their urinary systems with a program of catheterization. Bowel management programs aimed at improving elimination are also designed.
- Ophthalmologists evaluate and treat complications of the eyes.
- Orthotists design and customize various types of assistive technology, including braces, crutches, walkers, and wheelchairs to aid in mobility. As a general rule, the higher the level of the spina bifida defect, the more severe the paralysis, but paralysis does not always occur. Thus, those with low levels may need only short leg braces, whereas those with higher levels do best with a wheelchair, and some may be able to walk unaided.
- Physical therapists, occupational therapists, psychologists, and speech/language pathologists aid in rehabilitative therapies and increase independent living skills.
In terms of management, unless the syndrome results in other medical problems, treatment for endocrine dysfunction associated with pituitary malfunction is symptomatic and thus supportive;however, in some cases, surgery may be needed.
Operations to correct the malformations of the skull should be performed within the first year of infancy in patients affected by Carpenter Syndrome. Performing surgery at a young age increases the likelihood of obtaining a greatly improved appearance of the head because modifying bone is much easier to do when the skull is still constantly growing and changing.
In surgery the doctor breaks the fused sutures to allow for brain growth. Doctors remove the cranial plates of the skull, reshape them and replace them back onto the skull in an attempt to reshape the head to appear more normal. Although the sutures are broken during surgery they will quickly refuse, and in some cases holes form in the plates allowing cerebral spinal fluid to escape into cyst like structures on the external surface of the head.
If an individual with Carpenter Syndrome has a serious heart defect they will require surgery to correct the malformation of the heart. Other elective surgeries may also be performed. Some parents opt to have their child’s webbed fingers or toes separated which improves their appearance but not necessarily the functionality of the digits. In order to address the occupational challenges of the disease, many children with Carpenter Syndrome go through speech and occupational therapy in order to achieve more independence in everyday tasks and activities (RN, 2007).
In order to address the vision problems that are associated with bicoronal craniosynostosis, the individual must seek consultation from an ophthalmologist. If the palate is severely affected dental consultation may be necessary to correct the malformation. Obesity is often associated with Carpenter Syndrome, so a lifelong diet plan is often utilized to maintain a healthy weight. In addition surgery must be performed if the testes fail to descend (Paul A. Johnson, 2002). If the procedure is not performed the individual will become infertile.
In 1996, the United States Food and Drug Administration published regulations requiring the addition of folic acid to enriched breads, cereals, flour and other grain products. It is important to note that during the first four weeks of pregnancy (when most women do not even realize that they are pregnant), adequate folate intake is essential for proper operation of the neurulation process. Therefore, women who could become pregnant are advised to eat foods fortified with folic acid or take supplements in addition to eating folate-rich foods to reduce the risks of serious birth defects.
In Canada, mandatory fortification of selected foods with folic acid has been shown to reduce the incidence of neural tube defects by 46%.
Women who may become pregnant are advised to get 400 micrograms of folic acid daily. Women who have previously given birth to a child with a neural tube defect may benefit from a supplement containing 4.0 mg/5.0 mg in the UK mg daily, following advice provided by their doctor.
When surgery is indicated, the choice of treatment is based on the classification. Table 4 shows the treatment of cleft hand divided into the classification of Manske and Halikis.
Techniques described by Ueba, Miura and Komada and the procedure of Snow-Littler are guidelines; since clinical and anatomical presentation within the types differ, the actual treatment is based on the individual abnormality.
Table 4: Treatment based on the classification of Manske and Halikis
The timing of surgical interventions is debatable. Parents have to decide about their child in a very vulnerable time of their parenthood. Indications for early treatment are progressive deformities, such as syndactyly between index and thumb or transverse bones between the digital rays. Other surgical interventions are less urgent and can wait for 1 or 2 years.
At the beginning of the surgery a tourniquet will be applied to the limb. A tourniquet compresses and control the arterial and venous circulation for about 2 hours. The constriction band must be dissected very carefully to avoid damaging the underlying neurovasculature. When the constriction band is excised, there will be a direct closure. This allows the fatty tissue to naturally reposition itself under the skin.
“With complete circumferential constriction bands, it is recommended that a two-stage correction approach be used. At the first operation, one-half of the circumference is excised and the other one-half can be excised after three to six months. This will avoid any problems to the distal circulation in the limb, which may already be compromised. Lymphedema, when present, will significantly improve within a few weeks of the first surgery.”
For the direct closure of the defect after dissecting a constriction band there are two different techniques:
1. Triangular flaps; For this technique the circumference between the two borders must be measured. Depending on the difference the number of triangular flaps can be decided. With a triangular flap you can create more skin.
2. Z/W-plasty; “Z-plasty is a plastic surgery technique that is used to improve the functional and cosmetic appearance of scars. It can elongate a contracted scar or rotate the scar tension line. The middle line of the Z-shaped incision (the central element) is made along the line of greatest tension or contraction, and triangular flaps are raised on opposite sides of the two ends and then transposed.”
In rare cases, if diagnosed in utero, fetal surgery may be considered to save a limb that is in danger of amputation or other deformity. This operation has been successfully performed on fetuses as young as 22 weeks. The Melbourne's Monash Medical Centre in Australia, as well as multiple facilities in the United States of America, have performed successful amniotic band release surgery.
Surgical correction is recommended when a constriction ring results in a limb contour deformity, with or without lymphedema.
In the treatment of a brain cavernous hemangioma, neurosurgery is usually the treatment chosen. Research needs to be conducted on the efficacy of treatment with stereotactic radiation therapy, especially on the long-term. However, radiotherapy is still being studied as a form of treatment if neurosurgery is too dangerous due the location of the cavernoma. Genetic researchers are still working on determining the cause of the illness and the mechanism behind blood vessel formation. Clinical trials are being conducted to better assess when it is appropriate to treat a patient with this malformation and with what treatment method. Additionally, long term studies are being conducted because there is no information related to the long-term outlook of patients with cavernoma. A registry exists known as The International Cavernous Angioma Patient Registry collects information from patients diagnosed with cavernoma in order to facilitate discovery of non-invasive treatments.