Illustration of a spinal arachnoid cyst pressing on the spinal cord.

Unlocking Relief: Understanding and Managing Spinal Arachnoid Cysts

Beau Callahan in Health & Wellness August 2025 • 5 min read.

"Learn about spinal arachnoid cysts, their symptoms, and the latest surgical interventions to alleviate discomfort and improve neurological function."

Spinal arachnoid cysts (SACs) are uncommon lesions within the spinal canal, often discovered incidentally and typically asymptomatic. However, these cysts can sometimes exert mass effect, leading to a variety of neurological symptoms that may require intervention. Understanding these cysts, their origins, and the available treatment options is crucial for those affected and the medical professionals who care for them.

A spinal arachnoid cyst involves the herniation of the arachnoid mater and can arise from congenital anomalies or secondary factors like trauma, infection, inflammation, or even iatrogenic causes such as lumbar punctures. These cysts develop due to small defects in the arachnoid mater, causing cerebrospinal fluid (CSF) to accumulate, leading to membrane herniation. While the exact reasons for SAC development are not fully understood, several hypotheses attempt to explain their formation and progression.

When SACs become symptomatic, they can manifest in various ways, including pain, motor weakness, urinary incontinence, myelopathy, and sensory changes. These symptoms result from mass effect and nerve root compression, which can present either subacutely or chronically. The size of a cyst may increase with exercise or any activity that raises intracranial pressure, explained by a defect allowing CSF flow into the cyst. Recognizing these symptoms and understanding how they relate to cyst behavior is key to effective management.

Navigating Diagnosis and Treatment Strategies

Illustration of a spinal arachnoid cyst pressing on the spinal cord.

Diagnosing spinal arachnoid cysts involves a combination of thorough clinical evaluation and advanced imaging techniques. Magnetic Resonance Imaging (MRI) is the preferred diagnostic tool due to its high sensitivity and specificity in visualizing these cysts. MRI can reveal homogeneous, low-intensity signals on T1-weighted sequences and high-intensity signals on T2-weighted sequences, consistent with CSF characteristics. Newer MRI flow studies, employing cinematic techniques, can pinpoint dural defects by identifying pulsating flow voids.

Treatment approaches vary depending on whether the cysts cause symptoms. Asymptomatic cysts found incidentally often require only conservative management and monitoring. Symptomatic cysts, however, typically necessitate surgical intervention to alleviate pressure on the spinal cord and nerves. Surgical techniques are tailored to the cyst’s location and characteristics:

Extradural Cysts: Surgical resection with closure of the dural connection is favored. In challenging cases, a cystoperitoneal shunt may be necessary.
Intradural Cysts: Fenestration into the subarachnoid space is commonly performed, offering a high success rate with minimal risk of reaccumulation.
Anterior Cysts: Cervical corpectomy is performed, followed by a durotomy and complete resection of the cyst.

A recent study reviewed thirteen consecutive patients who underwent surgical intervention for SACs. The study found that the majority of cases were located in the thoracic spine (54%), with most being dorsal or dorsolateral. Pain was the most common presenting symptom (80%), and most patients experienced symptom improvement or complete resolution after surgery. Notably, extradural SACs were completely resected, while intradural SACs underwent fenestration. Postoperative outcomes indicated that pain and weakness were the most likely symptoms to improve, whereas sensory symptoms were less responsive to surgical intervention. These findings highlight the importance of tailored surgical approaches based on cyst location and individual patient presentation.

Looking Ahead: Improving Outcomes in Spinal Arachnoid Cyst Management

The management of spinal arachnoid cysts requires a nuanced approach, carefully balancing diagnostic accuracy with tailored treatment strategies. While surgery remains a cornerstone of care for symptomatic cysts, ongoing research and technological advancements promise to refine techniques and improve patient outcomes. Future directions may include minimally invasive approaches, enhanced imaging modalities, and personalized therapies that address the underlying mechanisms of cyst formation and symptom generation. By staying informed and embracing innovation, healthcare providers can continue to optimize the care and quality of life for individuals affected by this challenging condition.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1016/j.wneu.2018.11.005, Alternate LINK

Title: Surgical Management Of Spinal Arachnoid Cysts In Adults

Subject: Neurology (clinical)

Journal: World Neurosurgery

Publisher: Elsevier BV

Authors: Umit Eroglu, Melih Bozkurt, Gokmen Kahilogullari, Ihsan Dogan, Onur Ozgural, Kushal J. Shah, Murat Zaimoglu, Eyyub S.M. Al-Beyati, Hasan Caglar Ugur, Aaron A. Cohen-Gadol

Published: 2019-02-01

Everything You Need To Know

What are spinal arachnoid cysts, and how do they form?

Spinal arachnoid cysts (SACs) are lesions within the spinal canal that can sometimes exert mass effect, leading to neurological symptoms. They involve the herniation of the arachnoid mater and can arise from congenital anomalies or secondary factors like trauma, infection, inflammation, or even iatrogenic causes such as lumbar punctures. These cysts develop due to small defects in the arachnoid mater, causing cerebrospinal fluid (CSF) to accumulate, leading to membrane herniation. The exact reasons for SAC development are not fully understood, but hypotheses attempt to explain their formation and progression.

How do symptomatic spinal arachnoid cysts manifest, and what are the potential consequences of leaving them untreated?

When spinal arachnoid cysts (SACs) become symptomatic, they can manifest as pain, motor weakness, urinary incontinence, myelopathy, and sensory changes. These symptoms result from mass effect and nerve root compression. It's also important to note that the size of a cyst may increase with exercise or any activity that raises intracranial pressure, due to a defect allowing CSF flow into the cyst. If left unmanaged, the nerve compression could lead to permanent neurological deficits.

What imaging techniques are used to diagnose spinal arachnoid cysts, and why is MRI the preferred method?

Magnetic Resonance Imaging (MRI) is the preferred diagnostic tool due to its high sensitivity and specificity in visualizing spinal arachnoid cysts. MRI can reveal homogeneous, low-intensity signals on T1-weighted sequences and high-intensity signals on T2-weighted sequences, consistent with CSF characteristics. Newer MRI flow studies, employing cinematic techniques, can pinpoint dural defects by identifying pulsating flow voids. X-rays and CT scans are less useful but are still used to eliminate other pathology like tumors.

What are the different treatment options for spinal arachnoid cysts, and how is the choice of treatment determined?

Treatment approaches for spinal arachnoid cysts (SACs) vary depending on whether the cysts cause symptoms. Asymptomatic cysts found incidentally often require only conservative management and monitoring. Symptomatic cysts typically necessitate surgical intervention to alleviate pressure on the spinal cord and nerves. Surgical techniques are tailored to the cyst’s location and characteristics, such as surgical resection, cystoperitoneal shunt, fenestration into the subarachnoid space, or cervical corpectomy depending on the location, size, and severity of the cyst.

What were the key findings of the recent study on surgical interventions for spinal arachnoid cysts, and what do these findings suggest about treatment strategies?

A recent study reviewed patients who underwent surgical intervention for spinal arachnoid cysts (SACs), finding that the majority of cases were located in the thoracic spine (54%). Pain was the most common presenting symptom (80%), and most patients experienced symptom improvement or complete resolution after surgery. Extradural SACs were completely resected, while intradural SACs underwent fenestration. Postoperative outcomes indicated that pain and weakness were the most likely symptoms to improve, whereas sensory symptoms were less responsive to surgical intervention. These findings highlight the importance of tailored surgical approaches based on cyst location and individual patient presentation.