The Pipeline embolization device has got FDA approval
The 'Flow divertors' are being promoted as an exciting new tool for endovascular treatment of aneurysms previously untreatable, i.e large/giant, serpentine, fusiform, dissecting, blisters etc.
Various exercises were done in the past for these lesions, some successful, some not. The most useful was the concept of flow diversion by some means, which usually entailed sacrificing one or more vessels. The new stent flow divertors -Silk form Balt and Pipeline from eV3 maintain the patency of the arteries while shrinking and healing the aneurysm wihtout the need for open surgery or coiling. The FDA approval of pipeline stent in this regard is a major milestone, even though the real usefulness and harms of the device are significantly unknown. Have a look at the screenshot of the FDA page below.
Various exercises were done in the past for these lesions, some successful, some not. The most useful was the concept of flow diversion by some means, which usually entailed sacrificing one or more vessels. The new stent flow divertors -Silk form Balt and Pipeline from eV3 maintain the patency of the arteries while shrinking and healing the aneurysm wihtout the need for open surgery or coiling. The FDA approval of pipeline stent in this regard is a major milestone, even though the real usefulness and harms of the device are significantly unknown. Have a look at the screenshot of the FDA page below.
Read More
Add your Comment
0
comments
Patient Resources: Subarachnoid Hemorrhage
Subarachnoid hemorrhage (SAH)
The brain is covered by three layers of membranes. From outside in they are: dura, arachnoid, and pia. The spaces between these layers and brain contain fluid and blood vessels. SAH means bleeding (or hemorrhage in medical terms) in the area/space between the brain and the arachnoid membrane. This area is called the subarachnoid space.
Causes of Subarachnoid hemorrhage
Ø Bleeding from an aneurysm
Ø Bleeding from an arteriovenous malformation (AVM)
Ø Bleeding disorder
Ø Use of blood thinning medicines
Ø Injury-related subarachnoid hemorrhage
Ø Unknown cause (idiopathic)
SAH caused by an aneurysm that breaks open (ruptures) occurs in about 40 - 50 out of 100,000 people over age 30. SAH due to rupture of aneurysm is most common in persons ages 20 to 60. It is slightly more common in women than men.
Risks include:
Ø Smoking
Ø High blood pressure
Ø Aneurysm in other blood vessels
Ø Fibromuscular dysplasia (FMD) and other connective tissue disorders
Ø History of polycystic kidney disease
Ø A strong family history of aneurysms
Symptoms
The main symptom is a severe headache that starts suddenly and is often worse near the back of the head. Patients often describe it as the "worst headache ever" (called Thunderclap headache) and unlike any other type of headache pain. The headache may start after a popping or snapping feeling in the head.
Other symptoms:
Ø Nausea and vomiting
Ø Eye discomfort in bright light (photophobia)
Ø Stiff neck
Ø Decreased consciousness and alertness
Ø Mood and personality changes, including confusion and irritability
Ø Muscle aches (especially neck pain and shoulder pain)
Ø Numbness in part of the body
Ø Weakness of one or more limbs
Ø Seizure
Ø Vision problems, including double vision, blind spots, or temporary vision loss in one eye; Eyelid drooping; Pupil size difference
Investigations:
If your doctor thinks you may have a subarachnoid hemorrhage, a CT scan of head (without contrast) should be done right away. In 5-10% of cases, the scan may be normal, especially if there has only been a small bleed. If the CT scan is normal, a lumbar puncture (spinal tap) may be performed. In this, a thin needle is inserted in the spine and small amount of fluid is aspirated and sent for laboratory exam to look for evidence of bleeding.
Following confirmation of bleeding (based upon clinical findings, CT scan or lumbar puncture) other tests will be done to look for the disease causing the bleeding.
Ø Angiography of blood vessels of the brain. Angiography means ‘study of the blood vessels’. It can be done with CT (CT angiography), MRI (MR Angiography) or DSA (Digital subtraction angiography). Of these, DSA is the best and preferred test but more invasive. DSA is done by doctors trained in subject called ‘neurointervention’ and have traditionally been performed by interventional neuro-radiologists (now neurosurgeons and neurologists also have are doing it).
Treatment
The goals of treatment are to:
Ø Save your life
Ø Prevent complications such as permanent brain damage (stroke)
Ø Repair the cause of bleeding
Ø Relieve symptoms
A person who is conscious may need to be on strict bed rest. The person will be told to avoid activities that can increase pressure inside the head, including:
Ø Bending over
Ø Straining
Ø Suddenly changing position
Ø Coughing
Treatment for coma or decreased alertness includes:
Ø Life support
Ø Methods to protect the airway
Ø Special positioning
Ø External ventricular drainage to decrease the rising pressure inside the skull (hydrocephalus)*
Treatment will also include:
Ø Medicines given through an intravenous line to control blood pressure
Ø Nimodipine to prevent artery spasm**
Ø Painkillers and anti-anxiety medications to relieve headache and reduce pressure in the skull
Ø Phenytoin or other medications to prevent or treat seizures
Ø Stool softeners or laxatives to prevent straining during bowel movements
Surgery may be done to:
Ø Remove large collections of blood***
Ø Relieve pressure on the brain****
Ø Repair the aneurysm if the hemorrhage is due to an aneurysm rupture*****
Ø If the patient is critically ill, surgery may have to wait until the person is more stable.
*External ventricular drainage for hydrocephalus: Inside the skull and surrounding the brain is fluid (Cerebrospinal fluid or CSF) which is being constantly produced, circulating and going out of the skull. With bleeding, the fluid is not able to go out. This increases the pressure inside the skull and compresses the brain. The brain has hollow cavities inside called as ventricles. The fluid starts accumulating inside the ventricles which start to balloon out. The condition is called as ‘hydrocephalus’. It develops on one fourth of the patients. To treat it a thin tube in inserted in the ventricle though the skull via a minor surgery and connected to a drainage bag outside. The duration required is usually a week to 10 days. Rarely the patients may need permanent drainage. In such situations, internal drainage procedure is done. In this, a tube is connected from the ventricles to the abdominal cavity and left behind.
** Artery spasm (vasospasm): In about one fourth of patients, the blood vessels of the brain undergo spasm (spontaneous and prolonged narrowing). This can cause decrease in the blood flow to some areas of brain and cause permanent damage. To prevent and treat this condition certain treatment options are available: medications like nimodipine which can be given intravenously of intra arterially, Triple H therapy, and balloon angioplasty (in this we take a small balloon via the artery and inflate at the site of narrowing so as to dilate it).
*** Craniotomy (cutting a hole in the skull): may be required if large blood clots have formed in the brain so as to decrease the pressure over the brain.
**** To relieve pressure over the brain, craniotomy may be done; intravenous medications are also given and control the pressure to a large extent.
*****Aneurysm repair
Aneurysm is a local abnormal swelling of the artery like a balloon. With time this balloon keeps increasing in size and weakens, eventually the wall of the aneurysm becomes very thin and friable and gives way causing leakage of the blood. The blood leakage is stopped by the spontaneous vasospasm and by the pressure of the blood clot surrounding the aneurysm. However the aneurysm can give way again and again. To prevent this, the aneurysm has to be repaired. This can be done by two means: 1) Open surgery – in this, after opening up the skull, small titanium clip is applied at the base (neck) of the aneurysm so as to stop any blood from entering the aneurysm; 2) Endovascular coiling – via the same route as the angiography procedure, a very thin tube (microcatheter) is navigated into the aneurysm and through it one or more spring like coils made of platinum are deposited inside the aneurysm to completely fill it.
Whatever method is chosen, it is imperative to secure the aneurysm as early as possible because repeat bleed form the aneurysm has extremely high chances of death (as high as 75%). Also, during the course of the disease, doctors will increase the blood pressure of the patient, doing which can re-rupture the aneurysm.
Management in non- aneurismal causes of SAH:
- If no vascular pathology is found on DSA, the patients usually have good recovery. They will be put on medications, have to avoid exertion of any sort and undergo repeat DSA after 6 weeks. Sometimes, a lesion will be picked up on the repeat DSA.
- Arterio-venous malformation (AVM) of the brain: An AVM is an abnormal tangle of blood vessels on the surface or inside the brain formed congenitally during development of the vascular system. Usually they cause bleeding in the brain substance (intra-parenchymal hemorrhage, also called ICH) or intraventricular hemorrhage ( bleeding the cavities of the brain), also known as IVH. Occasionally, however small AVMs can cause isolated SAH. These AVMs will be picked up on the DSA and accordingly treated. SAH due to AVM usually has good prognosis.
- Venous thrombosis: Clot formation inside the veins (which carry blood away from the brain) can raise pressure in the areas drained by that particular vein, and can cause rupture of small tributary veins. The DSA will show involvement of only the larger veins. These patients also usually have good prognosis.
- Call Fleming syndrome (also known as reversible vasoconstriction syndrome): These patients have SAH clinically and on CT. DSA will show narrowing of one or more blood vessels but no other significant treatable pathology is found. These patients will be managed with medicines and usually respond well. A DSA done after 6 weeks usually will show normalization of the blood vessels.
- Vasculitis: A group of diseases involve primarily the blood vessels. There is inflammation followed by narrowing or dilatation of the arteries. A variety of individual diseases with various etiologies are included. A battery of investigations will be done if clinical features and DSA suggest vasculitis, and accordingly treated with medicines.
- Dissection of the artery: Artery is made of multiple layers. Sometimes, blood flowing inside the blood vessel can injure the innermost layer and travel through the various layers and eventually come out outside producing SAH. There are many causes of dissections, many times no cause is found. The patients can present differently with different treatment options and prognosis.
Expectations (prognosis):
How well a patient with SAH does will depend on many different factors:
- Location of bleeding
- Amount of bleeding
- Older age
- More severe symptoms at onset of disease
- Complications:
- repeat bleeding: very poor prognosis
- vasospasm
- hydrocephalus
- infarcts ( permanent areas of damage) in the brain
- Complications of surgery or embolization
- Medication side effects
- Seizures: the patient is put on medications before they develop seizures. These medications may continue for few months after discharge as well.
- Pre-existing or fresh diseases of other parts of the body: These patients are prone to develop involvement of the lungs and kidneys. The ICU team of doctors and nurses keep regular vigil with regular investigations for the same.
Read More
Add your Comment
0
comments
Patient Resources: Neurointervention and Interventional Neuroradiology
Neurointervention (Interventional Neuroradiology, Endovascular Neurosurgery, Interventional Neurology) refers to a set of minimally invasive techniques of treating certain diseases encountered in the medical practices of neuroradiologists, neurologists and neurosurgeons.
It is one of the most technologically advanced medical field and demands very high levels of disease understanding, in-depth subject knowledge, highly skilled sets of hands, courage, academic orientation and ability to look into the future.
Doctors from various backgrounds learn this art and super-specialize. These include radiologists, neurosurgeons and neurologists and they are called interventional neuroradiologists, endovascular neurosurgeons and interventional neurologists respectively, each of these terms though mean the same.The training of neurointerventionists involves radiological work, clinical neurology, ICU management and the cathlab work. It is a truly interdisciplinary medical field. The initial discovery of neuro-angiography was made of Egas Moniz, a neurophysician, as well as by Japanese neurosurgeons. However, the field was developed, techniques perfected and guidelines setup by neuroradiologists. With the advent of better equipments and infusion of high end technology, the ability to do therapeutic procedures has increased drastically over the last 25 years. This has brought about the interest of neurologists and neurosurgeons resulting in a truly dynamic amalgamation of various fields and thoughts.
What do interventional neuroradiologists do?
It is one of the most technologically advanced medical field and demands very high levels of disease understanding, in-depth subject knowledge, highly skilled sets of hands, courage, academic orientation and ability to look into the future.
Doctors from various backgrounds learn this art and super-specialize. These include radiologists, neurosurgeons and neurologists and they are called interventional neuroradiologists, endovascular neurosurgeons and interventional neurologists respectively, each of these terms though mean the same.The training of neurointerventionists involves radiological work, clinical neurology, ICU management and the cathlab work. It is a truly interdisciplinary medical field. The initial discovery of neuro-angiography was made of Egas Moniz, a neurophysician, as well as by Japanese neurosurgeons. However, the field was developed, techniques perfected and guidelines setup by neuroradiologists. With the advent of better equipments and infusion of high end technology, the ability to do therapeutic procedures has increased drastically over the last 25 years. This has brought about the interest of neurologists and neurosurgeons resulting in a truly dynamic amalgamation of various fields and thoughts.
What do interventional neuroradiologists do?
- They work in cathlabs (angiography suits)
- They enter the blood vessel to the brain as well as inside the brain with minimally invasive techniques via small needles in the arm or thigh and perform various procedures. These procedure include: DSA (Digital Substraction Angiography), Coiling of aneurysms, embolization of arteriovenous malformations and dural arteriovenous fistula of brain and spine, angioplasty and stenting of various blood vessels to prevent stroke, acute stroke treatment, embolization of tumors.
- Direct puncture and embolization of vascular malformations of face and skull
- Direct puncture in spine to perform a variety of procedure: vertebroplasty, kyphoplasty, discography, procedures to relieve back pain etc.
- They work closely with clinicians, surgeons, anesthesists, intensivists in the overall management of patients with brain hemorrhage, acute or chronic stroke, neck and back ache and vascular lesions of the head and neck and spine.
Various diagnostic angiograms (DSA) for head, neck and spine (Cerebral DSA, Carotid DSA, Spinal DSA) - Aneurysm coiling: simple, balloon assisted, stent assisted
- Spasmolysis: treatment for vasospam developing in the course of subarachnoid hemorrhage
- Arterio-venous malformation embolization
- Dural arterio-venous fistula embolizaation
- Angioplasty and stenting for intracranial arterial stenosis
- Preoperative or curative embolization of tumors located in head, face, neck and spine
- Treatment of epistaxis (bleeding from nose)
- Treatment of uncontrolled bleeding after trauma/injury to head, neck and face
- Carotid artery angioplasty with stenting
- Vertebral artery angioplasty with stenting
- Intra-arterial thrombolysis in cases of acute stroke
- Inferior petrosal sinus sampling for Cushing's syndrome and disease
- Intracranial venous stenting for stenosis and intracranial venous hypertension
- Acute intracranial dural venous sinus thrombosis treatment
- Neck and chest venous angioplasty and stenting for multiple sclerosis
- Direct percutaneous embolization for cranio facial vascular malformations and tumors
- Vertebroplasty
- Kyphoplasty
- Cisternography
- Myelography
- Discography
- Spinal biopsy
- Vertebral hemangioma embolization
- Neck and back pain relief procedures: facetal block, nerve block, epidural injections, foraminal block, RFA ablation, ozone therapy etc.
Diseases typically dealt by neurointerventionists:
- Brain hemorrhage
- Stroke ('Brain attack'/paralysis)
- Acute stroke
- Recurrent stroke or transient ischemic attacks
- Arterial dissection
- Vascular malformations of brain and spine ( AVM and Dural AVF)
- Cranio-facial vascular malformations
- Venous sinus thrombosis, occlusion or stenosis
- Multiple sclerosis
- Brain and spinal tumors
- Back and neck pain
Read More
Add your Comment
0
comments
Why we need computers ?
"Computers are incredibly fast, accurate and stupid; humans are incredibly slow, inaccurate and brilliant; together they are powerful beyond imagination." -- Albert Einstein
Read More
Add your Comment
0
comments
dual volume reconstruction from 3d rotational dsa
We all know the significance of 3D views in angiographic evaluation, whether it be CTA, MRA or DSA.
3D DSA provides the best quality images of course, because of the superior spatial resolution, contrast resolution, selective vessel catheterisation, high contrast densities achieved etc. It has been used extensively and is now indispensable, in fact, a must for patients undergoing evaluation of aneurysms.
However, all these techniques have limitations when it comes to evaluation of the follow up imaging of clipped or coiled aneurysms.
CTA is OK for clipped aneurysms but not for coiled ones while CE-MRA hold good for the opposite.
3D DSA can also be marred by the artefacts. In fact, 2D DSA runs often are the best!. However, the recent advancements in the 3D reconstruction technology have made things easier.
Now we have 3d road mapping, fusion DSA, DynaCT etc. A noticeable one is the dual volume reconstruction in which the two acquired data volumes (the mask run and the contrast run) are reconstructed separately and then fused together, with each volume being modifiable individually to give the desired contrast, windowing and colour coding.
Illustrative examples:
Case 1: Immediate post coiling 3D angiogram to look for residue
Post coiling 3D angiogram with dual volume recon on an Acom aneurysm showing the coil mass in silver and the contrast filled arteries in golden brown. The aneurysm is well coiled with no residue. However the base of the coil mass is irregular indicating freshly done procedure. With time, base is likely to be covered up with endothelium and the arterial outline would become smooth.
Case 2: 2D and 3D angiograms in a post clipping regrown aneurysm
Routine angiograms showing a ventral ICA aneurysm with a surgical clip overlying the neck region. The exact relation ship of the clip with the aneurysm and the parent vessel is impossible to make out
Routine DSA image native view showing the clip and the arterial tree in relation to the bones.
3D run volume rendered image showing the aneurysm and the parent artery well with excellent depiction of the aneurysm morphology. However the clip is not seen as it has got subtracted. Note however that there is a groove over the neck of the aneurysm.
Dual volume reconstruction images with dual colour coding showing the clip and the aneurysm with their interrelationship very nicely. the clip is totally free for the parent vessel and is abutting a very small portion of the aneurysm. It should be relatively easy to coil this aneurysm.
Case 3: Angiogram in a case of previously coiled Acom and left MCA aneurysms
2D DSA and 3D DSA run with volume rendering showing coiled left MCA and Acom aneurysms. There are contrast filled outpouchings seen at both locations again. However, it is difficult to evaluate the aneurysms, parent arteries and the coil mass inter-relationship. We do not know whether these are regrown aneurysms or new ones adjacent to the previously coiled ones.
Dual volume images show clearly that the MCA aneurysm has regrown and a fresh 'kissing’ aneurysm has come up at Acom adjacent to the previous one. clear visualisation of the parent artery, the arterial branches, aneurysm neck and the coil mass is apparent .
Read More
Add your Comment
0
comments
Fenestrated Posterior Inferior Cerebellar Artery with Concomitant Vertebro-Basilar Junction Fenestration and Vertebral Artery Aneurysm
My recently published paper
S. Kumar, E. M. Justin & N. K. Mishra. Fenestrated Posterior Inferior Cerebellar Artery with Concomitant Vertebro-Basilar Junction Fenestration and Vertebral Artery Aneurysm. Clin Neuroradiol DOI 10.1007/s00062-011-0070-9
Download from
http://www.mediafire.com/?3obcqo32olo3n9i
Read More
Add your Comment
0
comments
