The administration of stents in medical care has been extensive in the past few years. Stents are tiny web like structures made with wire; often with a mesh-like appearance. They are used in expanding a narrowed blood vessel in conditions such as coronary artery disease. The mechanical support provided by the stent plays a significant role in preventing the reoccurrence of arterial blockage. Stents are predominantly administered in arteries associated with the brain, thorax, abdomen, coronary and peripheral organs.
The incorporated stent exerts an outward pressure to open the lumen in dilating the blood vessel and the pressure exerted has to be monitored carefully during the procedure. There are many different types of stents available and all of them have specific parameters based on which they have been classified as avascular, non vascular, coronary and peripheral types. Stents are engineered to have low elasticity and high stress capability. Some stents are balloon incorporated for their release mechanism and others are delivered and expanded.
These type of stents are administered in conditions such as atherosclerosis, aneurysm and coronary artery diseases. Many procedures such as the balloon valvuloplasty, :Angioplasty prefer the incorporation of stents that can be expanded by using a balloon catheter in the region of blockage. With this, the risk of arterial re- narrowing is avoided. Application of coronary stents have become very extensive in contemporary cardiac procedures.
These stents are used in portal vein stenosis, a condition in which the artery supplying blood to the liver, pancreas and the abdominal region is obstructed. In most cases these obstructions occur in malignant tumors or cancers of the hepatic or biliary region. Many studies indicate that the administration of portal stents have facilitated significant progress in the functionality of the liver in relieving portal hypertension.
Non vascular stents
The use of stents was initially limited to vascular diseases. Recent studies indicate the increase in the use of stents in nonvascular conditions are related to gastrointestinal system, urinogenital system and also in the tracheo bronchial region.
Drug eluting stents
These stents are also used in cardiac conditions. They have a specific role in the treatment of coronary artery disease. They are used to reduce the inflammation and cell proliferation in the artery when the stent is introduced.
These stents are used predominantly to clear the obstruction that is present in the urethral passage . In most cases it is administered in renal or urethral malignancies to clear the urine. The only discomfort in these stents are that they tend to cause itching and irritation.
Restenosis refers to the re-narrowing of the coronary artery after an Angioplasty procedure. It literally means reoccurrence of the stenosis (narrowing of the blood vessel). Restenosis occurs within 3-6 moths in 40-50% of people who have undergone an Angioplasty.
During the procedure of angioplasty a balloon is inserted into the blocked artery and inflated so as to allow the blood to flow normally to all portions of the heart. During this procedure the surrounding tissues undergo trauma and become susceptible for damage. Restenosis may set in during thrombosis or due to fresh tissue growth at the site of the surgery. Restenosis does not indicate progression of the heart disease but may be an indication that the body's immune system is responding to the injury caused during angioplasty.
Modern medicine has seen the use of stents to keep the artery open. Usage of stents has brought down restenosis considerably. Usage of drug-eluting stent allows slow seepage of medication that reduces proliferation of cells thus reducing re-clogging.
Restenosis causes and treatment
Restenosis is mainly caused due to a surgery that unblocks or widens a blood vessel. Treatment depends on the clinical condition:
Cystoscopy is done to examine and diagnose disorders of the urinary bladder and urinary tract. In this procedure, the internal structure of the urinary bladder and the urinary tract can be examined by using the cystoscope. Cystoscopes are administered as both diagnostic and treatment tools. Cystoscopy is predominantly done for patients experiencing recurrent urinary tract or bladder infection, urinary incontinence, hematuria and pain because of obstruction in the urinary tract. The procedure is performed by a urologist by inserting a tube called cystoscope through the urethra to identify disorder.
The duration of the procedure depends upon the condition of the patient. The procedure usually lasts about 45 minutes and it is performed under local, spinal or general anesthesia. Pathological specimens of the urinary bladder can also be obtained by using cystoscopes. Patients are advised to abstain from taking food or water six hours prior to the procedure. In case of rigid cystoscopy, the inserted cystoscope is used to remove any kind of lesions present in the urinary tract or the bladder. In the flexible cystoscopy procedure, the internal lining of the urinary bladder and the urinary tract are examined for abnormalities.
With cystoscopy, small bladder stones or foreign objects can be removed; thereby eliminating surgical intervention. Cystoscopy is useful in examining enlarged prostate, kidney stones and urethral blockage. This procedure is used to place urethral catheters or stents.
Complications of Cystoscopy
The complications associated with the cystoscopy procedure are mostly due to a perforation in the urinary tract. These perforations are caused during the procedure and might lead to urinary tract infection and bleeding. In men epididymitis occurs if testicles are involved during the procedure. The other complications include difficulty in passing urine and abdominal pain. In order to avoid the onset of urinary tract infection after the procedure patients are advised to take fluids preferably water every hour.
Bibliography / Reference
Collection of Pages - Last revised Date: March 21, 2019