Dolichoectasia means stretched out and bigger. It is used to identify arteries with severe tunica intima (and possibly tunica media) degeneration, which affects the vessel and causes the artery to dilate and distend. It is a disorder in which the vertebral and basilar arteries elongate, dilate, and become tortuous. Although this condition is infrequent and usually asymptomatic, it can occasionally cause compression of the brainstem, cerebral bleeding, or ischemic symptoms.
Dolichoectasia is more common in older people, and it is also linked to other typical cardiovascular risk factors. Multiple pathologic processes contribute to the formation of dolichoectatic arteries, and as a result, metalloproteinase activation and irregular tumultuous blood flow appear which cause irrevocable damage to the internal elastic lamina.
Dolichoectasia also rarely causes the compression of the third ventricle or the cerebral aqueduct, which appears as non-communicating hydrocephalus. This disease mostly affects the posterior circulation of the body.
VBD (Vertebrobasilar dolichoectasia ) develops without causing any symptoms. Clinical presentations differ greatly in cases with evident symptoms. Ischemic stroke is the most prevalent symptom, followed by compression of the brainstem and cranial nerves, hydrocephalus, and cerebral hemorrhage.
Ischemic stroke is the most prominent clinical sign of VBD and the leading cause of death. VBD has a two-way vertebrobasilar blood flow with a diminished forward flow. Although peak velocity appears to be constant in ultrasonic flow, the mean velocity is lowered. Reduced blood flow leads to hypoperfusion, which results in ischemic symptoms. Intraluminal thrombosis is also seen among patients with dolichoectasia. The other symptoms which can result from ischemia include endothelial injury, the formation of atherosclerosis, pulling and twisting of the branching vessels, and contralateral infarction.
The compression of the cranial nerves and the brainstem leads to the symptoms such as weakness, dizziness, choking on water, cranial nerve injury, or neurogenic hypertension inside the cranial fossa. VBD can cause obstructive hydrocephalus, which is a rare consequence. Most of the time, it is caused by problems with the flow of cerebrospinal fluid that come from direct or indirect pressure underneath the midbrain aqueduct.
The exact causes of dolichoectasia are not known completely. But some of the prevalent causes are as follows:
- Atherosclerosis caused by hypertension: Because VBD is more common in older male hypertensive patients, a long-held theory says that hypertension-induced atherosclerosis is a primary contributor to VBD occurrence. VBD-induced morphological and hemodynamic changes are also considered the cause of atherosclerosis.
- Factors of heredity/congenital factors: Dolichoectasia occurs in certain people due to their family history. This disease is mostly inherited from family members.
- The other factors that can cause dolichoectasia include, infection, such as syphilis infection, hyperlipidemia, or Hypercholesterolemia.
VBD is mostly found in the deepest areas of the brain. As most of the lesions are found over the whole length of the vertebrobasilar arteries, which supply numerous vital blood vessels, successful treatment remains a challenge. There is presently no exact and effective treatment for VBD and those that are available focus on specific symptoms or VBD consequences. The following treatment options are preferred for this disease:
Surgical treatment remains the most promising, despite the lack of a precise and successful treatment for VBD. When VBD occurs, the basilar and vertebral arteries expand tortuously along their whole length. In this therapy, removing the enlarged arteries and replacing them with new blood vessels takes place.
Ischemic stroke treatment:
Dolichoectasia is treated in certain cases by managing the ischemic stroke. In this case, antiplatelet medicines can help manage dolichoectasia by lowering the risk of recurrent ischemic stroke.
Treatment of brainstem and cranial nerve compression:
By treating cranial nerve and brainstem compression, VBD is managed. Microvascular decompression is the most successful therapy for VBD since all compression symptoms are caused by throbbing nerve root compression.
Treatment of Hemorrhage:
To treat hemorrhage, close monitoring and stringent blood pressure control are essential for patients with VBD, and antiplatelet medicines are used with caution. When VBD progresses, immediate surgical intervention is required.
The other way of managing dolichoectasia is by treating hydrocephalus. In this case, a unilateral ventriculoperitoneal shunt is adequate for the management.
Dolichoectasia vs Aneurysm
Dolichoectasia is an uncommon arteriopathy characterized by artery extension and enlargement as well as laminar blood flow disruption. It primarily affects the spinal and basilar arteries. Fusiform aneurysm development is possible in advanced cases.
Elongated dilations of cerebral arteries are known as fusiform aneurysms. Dolichoectasia is a term that can be used interchangeably to represent a less severe range of arterial dilatation and/or tortuosity. Aneurysms of the fusiform and dolichoectatic types can develop on their own or in conjunction with genetic problems, connective tissue illnesses, and atherosclerosis.