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The U.S. Preventive Services Task Force recommends a single screening ultrasound for abdominal aortic aneurysm in males age 65 to 75 years who have a history of smoking. There is an estimated number needed to screen of approximately 850 people. It is unclear if screening is useful in women aged 65 to 75 who have smoked and they recommend against screening in women who have never smoked.
Repeat ultrasounds should be carried out in those who have an aortic size greater than 3.0 cm. In those whose aorta is between 3.0 and 3.9 cm this should be every three years, if between 4.0 and 4.4 cm every two year, and if between 4.5 and 5.4 cm every year.
In the United Kingdom one time screening is recommended in all males over 65 years of age. Australia has no guideline on screening.
Abdominal aortic aneurysms are commonly divided according to their size and symptomatology. An aneurysm is usually defined as an outer aortic diameter over 3 cm (normal diameter of the aorta is around 2 cm), or more than 50% of normal diameter. If the outer diameter exceeds 5.5 cm, the aneurysm is considered to be large.
A ruptured AAA is a clinical diagnosis involving the presence of the triad of abdominal pain, shock, and a pulsatile abdominal mass. If these conditions are present, indicating AAA rupture, no further clinical investigations are needed before surgery.
There are three methods of scanning that detect angiomyolipoma: ultrasound, CT and MRI. Ultrasound is standard and is particularly sensitive to the fat in angiomyolipoma but less so to the solid components. However it is hard to make accurate measurements with ultrasound, particularly if the angiomyolipoma is near the surface of the kidney (Maclean Grade III). Computed tomography (CT) is very detailed and fast and allows accurate measurement. However, it exposes the patient to radiation and the dangers that a contrast dye used to aid the scanning may itself harm the kidneys. Magnetic resonance imaging (MRI) is safer than CT but many patients (particularly those with the learning difficulties or behavioural problems found in tuberous sclerosis) require sedation or general anaesthesia and the scan cannot be performed quickly. Some other kidney tumours contain fat, so the presence of fat isn't diagnostic. It can be difficult to distinguish a fat-poor angiomyolipoma from a renal cell carcinoma (RCC). Both minimal fat AMLs and 80% of the clear cell type of RCC display signal drop on an out-of-phase (OOP) MRI sequence compared to in-phase (IP). Thus, a lesion growing at greater than 5 mm per year may warrant a biopsy for diagnosis.
Incidental discovery of angiomyolipomas should trigger consideration of tuberous sclerosis complex (TSC) and lymphangioleiomyomatosis, especially if they are large, bilateral and/or multiple. Screening for TSC includes a detailed physical exam, including dermatologic and ophthalmologic evaluations, by TSC expert clinicians and a CT or MRI of the brain. Screening for LAM includes a high resolution CT of the lung and pulmonary function testing.
Since it is a rare disease, it remains a diagnosis of exclusion of other conditions with similar symptoms. The diagnosis is supported by the results of imaging studies such as computed tomography or magnetic resonance imaging, ultrasound of the abdomen (with or without doppler imaging) or intravenous urography.
Specialist vascular ultrasonographers should routinely look for left ovarian vein reflux in patients with lower limb varices especially if not associated with long or short saphenous reflux. The clinical pattern of varices differs between the two types of lower limb varices.
CT scanning is used to exclude abdominal or pelvic pathology. CT-Angiography/Venography can often demonstrate left ovarian vein reflux and image an enlarged left ovarian vein but is less sensitive and much more expensive than duplex Doppler ultrasound examination. Ultrasound requires that the ultrasonographer be experienced in venous vascular ultrasound and so is not always readily available. A second specialist ultrasound exam remains preferable to a CT scan.
As a wide range of pelvic and abdominal pathology can cause symptoms consistent with those symptoms due to left ovarian vein reflux, prior to embolisation of the left ovarian vein, a careful search for such diagnoses is essential. Consultation with general surgeons, gynaecologists, and possibly CT scanning should always be considered.
Mortality from aortic rupture is up to 90%. 65–75% of patients die before they arrive at hospital and up to 90% die before they reach the operating room.
Most myelolipomas are unexpected findings on CT scans and MRI scans of the abdomen. They may sometimes be seen on a plain X-ray films.
Fine needle aspiration may be performed to obtain cells for microscopic diagnosis.
Diagnosis is often suspected in patients "in extremis" (close to death) with abdominal trauma or with relevant risk-factors. Diagnosis is confirmed quickly in the Emergency room by ultrasound or CT scan.
The diagnosis of retroperitoneal fibrosis cannot be made on the basis of results of laboratory studies. CT is the best diagnostic modality: a confluent mass surrounding the aorta can be seen on a CT scan. Although biopsy is not usually recommended, it is appropriate when malignancy or infection is suspected. Biopsy should also be done if the location of fibrosis is atypical or if there is an inadequate response to initial treatment.
The long-term follow-up in individuals who survive aortic dissection involves strict blood pressure control. The relative risk of late rupture of an aortic aneurysm is 10 times higher in individuals who have uncontrolled hypertension, compared to individuals with a systolic pressure below 130 mmHg.
The risk of death is highest in the first two years after the acute event, and individuals should be followed closely during this time period. About 29% of late deaths following surgery are due to rupture of either a dissecting aneurysm or another aneurysm. In addition, a 17% to 25% incidence exists of new aneurysm formation, typically due to dilatation of the residual false lumen. These new aneurysms are more likely to rupture, due to their thinner walls.
Serial imaging of the aorta is suggested, with MRI being the preferred imaging technique.
A measurement of blood D-dimer level may be useful in diagnostic evaluation. A level less than 500 ng/ml may be considered evidence against a diagnosis of aortic dissection, although this guideline is only applicable in cases deemed "low risk" and within 24 hours of symptom onset. The American Heart Association does not advise using this test in making the diagnosis, as evidence is still tentative.
Everolimus is FDA approved for the treatment of angiomyolipomas. Treatment should be considered for asymptomatic, growing AML measuring larger than 3 cm in diameter.
Angiomyolipoma do not normally require surgery unless there is life-threatening bleeding. Some centres may perform preventative selective embolisation of the angiomyolipoma if it is more than 4 cm in diameter, due to the risk of haemorrhage.
People with tuberous sclerosis are advised to have yearly renal scans, though it is possible that patients with very stable lesions could be monitored less frequently. The research in this area is lacking. Even if no angiomyolipoma is found, one can develop at any life stage. The angiomyolipoma can grow rapidly.
In tuberous sclerosis, typically many angiomyolipomas affecting each kidney. It is not uncommon for more than one intervention to be required during lifetime. Since kidney function may already be impaired (up to half the kidney may be lost before function loss is detectable), it is vital to preserve as much kidney as possible when removing any lesion. Large angiomyolipomas are treated by embolisation which reduces the risk of haemorrhage and can also shrink the lesion. A side effect of this treatment is postembolisation syndrome: severe pain and fever however this is easily managed and lasts only a few days.
A ruptured aneurysm in an angiomyolipoma leads to blood loss that must be stopped (though embolisation) and compensated for (through intravenous fluid replacement). Therefore, removal of the affected kidney (nephrectomy) is strongly discouraged though may occur if the emergency department is not knowledgeable about tuberous sclerosis.
Embolisation involves inserting a catheter along the blood vessels to the tumour. The blood vessels are then blocked, typically by injecting ethanol or inert particles. The procedure can be very painful, so analgesics are used. The destroyed kidney tissue often causes post-embolisation syndrome, which manifests as nausea, vomiting, fever and abdominal pain, and lasts a few days. Embolisation (in general) has an 8% rate of morbidity and a 2.5% rate of mortality, so is not considered lightly.
Patients with kidney loss should be monitored for hypertension (and treated for it if discovered) and avoid nephrotoxic drugs such as certain pain relievers and IV contrast agents. Such patients who are unable to communicate effectively (due to age or intellectual disability) are at risk of dehydration. Where multiple or large angiomyolipomas have caused chronic kidney disease, dialysis is required.
Robotic assisted partial nephrectomy has been proposed as a surgical treatment of a ruptured angiomyolipoma combining the advantages both of a kidney preservation procedure and the benefits of a minimal invasive procedure without compromising the safety of the patient.
The risk of the development of a lymphocele is positively correlated to the extent of the removal of lymphatic tissue during surgery (lymphadenectomy). Surgery destroys and disrupts the normal channels of lymph flow. If the injury is minor, collateral channels will transport lymph fluid, but with extensive damage, fluid may accumulate in an anatomic space resulting in a lymphocele. Typical operations leading to lymphocysts are renal transplantation and radical pelvic surgery with lymph node removal because of prostatic or gynecologic cancer. Other factors that may predispose of lymphocele development are preoperative radiation therapy, heparin prophylaxis (used to prevent deep vein thrombosis), and tumor characteristics. After radical surgery for cervical and ovarian cancer studies with follow-up CT found lymphoceles in 20% and 32%, respectively. Typically they develop within 4 months after surgery.
It has been suggested that suction drains placed during surgery and non-peritonisation (not closing the posterior peritoneum) may reduce the possibility of lymphocele development.
Smaller lymphoceles can be managed expectantly, and many lesions will regress over time. For symptomatic lesions a number of approaches are available and include fine needle aspiration with US or CT guidance, catheter insertion and drainage (with possible use of sclerosants), and surgical drainage. Sex and masturbation may cause the lymphocele to grow if it is in the genital area. It is suggested to avoid these activities for around one to one and a half months. Some exercises may also help to shrink it.
Myelolipomas are usually found to occur alone in one adrenal gland, but not both. They can vary widely in size, from as small as a few millimetres to as large as 34 centimeters in diameter. The cut surface has colours varying from yellow to red to mahogany brown, depending on the distribution of fat, blood, and blood-forming cells. The cut surface of larger myelolipomas may contain haemorrhage or infarction.
The risk of meningioma can be reduced by maintaining a normal body weight, and by avoiding unnecessary dental x-rays.
Treatment consists of painkillers and surgical ablation of the dilated vein. This can be accomplished with open abdominal surgery (laparotomy) or keyhole surgery (laparoscopy). Recently, the first robot-assisted surgery was described.
Another approach to treatment involves catheter-based embolisation, often preceded by phlebography to visualise the vein on X-ray fluoroscopy.
Ovarian vein coil embolisation is an effective and safe treatment for pelvic congestion syndrome and lower limb varices of pelvic origin. Many patients with lower limb varices of pelvic origin respond to local treatment i.e. ultrasound guided sclerotherapy. In those cases, ovarian vein coil embolisation should be considered second line treatment to be used if veins recur in a short time period i.e. 1–3 years. This approach allows further pregnancies to proceed if desired. Coil embolisation is not appropriate if a future pregnancy is possible. This treatment has largely superseded operative options.
Coil embolisation requires exclusion of other pelvic pathology, expertise in endovascular surgery, correct placement of appropriate sized coils in the pelvis and also in the upper left ovarian vein, careful pre- and post-procedure specialist vascular ultrasound imaging, a full discussion of the procedure with the patient i.e. informed consent. Complications, such as coil migration, are rare but reported. Their sequelae are usually minor.
If a Nutcracker compression (see below) is discovered, stenting of the renal vein should be considered before embolization of the ovarian vein. Reducing outflow obstruction should always be the main objective.
Although often described as benign, a teratoma does have malignant potential. In a UK study of 351 infants and children diagnosed with "benign" teratoma reported 227 with MT, 124 with IT. Five years after surgery, event-free survival was 92.2% and 85.9%, respectively, and overall survival was 99% and 95.1%. A similar study in Italy reported on 183 infants and children diagnosed with teratoma. At 10 years after surgery, event free and overall survival were 90.4% and 98%, respectively.
Depending on which tissue(s) it contains, a teratoma may secrete a variety of chemicals with systemic effects. Some teratomas secrete the "pregnancy hormone" human chorionic gonadotropin (βhCG), which can be used in clinical practice to monitor the successful treatment or relapse in patients with a known HCG-secreting teratoma. This hormone is not recommended as a diagnostic marker, because most teratomas do not secrete it. Some teratomas secrete thyroxine, in some cases to such a degree that it can lead to clinical hyperthyroidism in the patient. Of special concern is the secretion of alpha-fetoprotein (AFP); under some circumstances AFP can be used as a diagnostic marker specific for the presence of yolk sac cells within the teratoma. These cells can develop into a frankly malignant tumor known as yolk sac tumor or endodermal sinus tumor.
Adequate follow-up requires close observation, involving repeated physical examination, scanning (ultrasound, MRI, or CT), and measurement of AFP and/or βhCG.
Treatment varies according to severity, ranging from monitoring of the hematoma (in haemodynamic stability) to emergency surgery (when patients develop hypovolemic shock requiring seminephrectomy or nephrectomy). Vascular causes lead to surgery due to severity of hemorrhage. Robotic-assisted partial nephrectomy has been proposed as a surgical treatment of a ruptured angiomyolipoma causing retroperitoneal hemorrhage, combining the advantages of a kidney preservation procedure and the benefits of a minimally invasive procedure without compromising the safety of the patient.
JCT often is described as benign, however one case of metastasis has been reported, so its malignant potential is uncertain. In most cases the tumor is encapsulated.
Clinically, hypertension, especially when severe or poorly controlled, combined with evidence of a kidney tumor via imaging or gross examination suggest a JCT. However, other kidney tumors can cause hypertension by secreting renin. JCTs have a variable appearance and have often being misdiagnosed as renal cell carcinomas; dynamic computed tomography is helpful in the differential diagnosis.
Post-operatively, the presence of renin granules in pathology specimens as well as immunohistochemical analyses could help differentiating this tumor from other primary renal tumors such as hemangiopericytoma, glomus tumor, metanephric adenoma, epithelioid angiomyolipoma, Wilms tumor, solitary fibrous tumor, and some epithelial neoplasms.
Depending on the grade of the sarcoma, it is treated with surgery, chemotherapy and/or radiotherapy.
Surgical decompression can be achieved by opening the abdominal wall and abdominal fascia anterior in order to physically create more space for the abdominal viscera. Once opened, the fascia can be bridged for support and to prevent loss of domain by a variety of medical devices (Bogota bag, artificial bur, and vacuum devices using negative pressure wound therapy ).
Extraspinal ependymoma, usually considered to be a glioma (a type of non-germ cell tumor), may be an unusual form of mature teratoma.
In the absence of severe urinary tract obstruction (which generally requires surgery with omental wrapping), treatment is generally with glucocorticoids initially, followed by DMARDs either as steroid-sparing agents or if refractory on steroids. The SERM tamoxifen has shown to improve the condition in various small trials, although the exact mechanism of its action remains unclear.
Associations include:
- Riedel's thyroiditis
- previous radiotherapy
- sarcoidosis
- inflammatory abdominal aortic aneurysm
- drugs
Observation with close imaging follow-up may be used in select cases if a meningioma is small and asymptomatic. In a retrospective study on 43 patients, 63% of patients were found to have no growth on follow-up, and the 37% found to have growth at an average of 4 mm / year. In this study, younger patients were found to have tumors that were more likely to have grown on repeat imaging; thus are poorer candidates for observation. In another study, clinical outcomes were compared for 213 patients undergoing surgery vs. 351 patients under watchful observation. Only 6% of the conservatively treated patients developed symptoms later, while among the surgically treated patients, 5.6% developed persistent morbid condition, and 9.4% developed surgery-related morbid condition.
Observation is not recommended in tumors already causing symptoms. Furthermore, close follow-up with imaging is required with an observation strategy to rule out an enlarging tumor.