Many concepts in medicine carry one meaning in everyday language and a far more specific one in clinical practice. Dissection is precisely such a concept. Derived from the Latin dissecare — “to cut apart” — this term carries two distinct yet interconnected meanings in medicine: one refers to a surgical technique, the other to a serious pathological process.
Dissection as a Surgical Technique
In the operating theatre, dissection refers to the process of separating tissues layer by layer without disrupting their architecture. A surgeon carefully separating vessels and nerve fibers one by one to reach an aneurysm neck, peeling a brain tumor away from healthy tissue, or gently passing through muscle layers during a spinal procedure — all of these are different expressions of dissection. Good dissection is not cutting; it is understanding. It is knowing a structure well enough to separate it without harming it. For this reason, surgical dissection is more than a technical skill — it is an art in which anatomical knowledge and tactile experience converge.
Dissection as a Pathological Process
The second and far more critical meaning of dissection describes the pathological process that develops when blood infiltrates between the layers of a vessel wall. In this context, dissection is a disease.
A normal vessel wall consists of three fundamental layers from inside out: the intima, the media, and the adventitia. When a tear or crack develops in the intima for any reason, pressurized blood seeps through this opening into the vessel wall and advances between the layers, creating a false lumen — a second channel running alongside the true vascular pathway. The entirety of this process is called arterial dissection.
In Which Vessels Does It Occur?
Arterial dissection can develop in any vessel in the body; however, the clinically most significant locations are the major arteries of the head and neck. Carotid artery dissection and vertebral artery dissection are among the leading causes of ischemic stroke in young adults in particular. Intracranial dissections are less common, but because they can lead to subarachnoid hemorrhage, they can follow a far more dangerous course.
Why Does It Develop?
The triggers of dissection span a wide spectrum. Trauma is the most frequently encountered cause: a traffic accident, a sports injury, a sudden neck movement, or even a severe coughing fit can trigger dissection. Connective tissue diseases such as fibromuscular dysplasia, Marfan syndrome, and Ehlers-Danlos syndrome structurally weaken the vessel wall and lay the groundwork for dissection. In some cases, no identifiable cause can be found — this is referred to as spontaneous dissection.
What Is the Clinical Picture?
Arterial dissection can present with two distinct clinical pictures.
In the ischemic picture, the false lumen expands and narrows or completely occludes the true vascular channel. In addition, thrombus fragments forming at the dissection site can be carried to cerebral vessels, causing embolic infarction. Both mechanisms result in ischemic stroke.
In the hemorrhagic picture, the dissection extends beyond the adventitia and into the subarachnoid space, causing subarachnoid hemorrhage. This second presentation is far more common in intracranial dissections and constitutes an emergency requiring immediate intervention.
How Is the Diagnosis Made?
MR angiography and CT angiography are the first-line modalities in diagnosing dissection. On MR imaging, the accumulation of blood within the vessel wall — the intramural hematoma — is the most reliable sign of dissection. On digital subtraction angiography, a double lumen appearance, an intimal flap, and irregular vessel calibration are among the characteristic findings.
How Is Treatment Planned?
The treatment approach is individualized according to the location of the dissection, the clinical picture, and the patient’s overall condition. In the ischemic picture, anticoagulant or antiplatelet therapy takes the lead. In the hemorrhagic picture, endovascular or surgical intervention becomes necessary. Among endovascular options, flow diverter stent placement, trapping, and reconstructive stenting can be considered. On the surgical side, trapping and bypass procedures are preferred in appropriate cases.
Conclusion
Dissection is a multilayered concept that reflects two distinct faces of medicine — both as a surgical technique and as a serious vascular pathology. Viewed in its pathological sense, early recognition, accurate imaging, and an individualized treatment strategy are the indispensable conditions for successful management.
Prof. Dr. Mehmet Şenoğlu — Neurosurgeon, İzmir
Disclaimer: The information in this article is intended for general informational purposes only. It does not constitute personal medical advice and cannot replace a face-to-face consultation with a physician.