Sacral extradural arachnoid cyst in association with split cord malformation

Intrasacral meningoceles: Clinical presentation, surgical management, and postoperative outcome: The Giannina Gaslini Hospital's experience

INTRODUCTION

Intrasacral meningoceles are cysts associated with herniating arachnoid with no nerve root within due to an area of weakness of the dura mater. They are thought to be congenital, but they are usually not symptomatic until adulthood. Surgical treatment is generally indicated in the presence of symptoms.

METHODS

We selected cases belonging to the IB category of Nabors et al.'s classification who underwent surgery between 2008 and 2021 at Giannina Gaslini Hospital. Exclusion criteria were prior history of trauma, infections, or operations. Patients' clinical details, associated conditions, surgical techniques, peri- and postoperative complications, and outcomes were collected retrospectively from clinical charts. We compared our series to literature: keywords "intrasacral meningocele" were used on the search engine MEDLINE - Pubmed.

RESULTS

We identified 23 cases: 5 of the 14 symptomatic patients had a complete resolution, and 5 had a substantial clinical improvement after surgery. Cyst recurrence and major postoperative complication occurred in none. Among 59 articles considered for evaluation, 50 were excluded and remaining 9 articles underwent full-text analysis.

DISCUSSION AND CONCLUSION

The pathogenesis of instrasacral meningoceles is still not completely understood and the spectrum of symptoms is wide. A posterior surgical approach with sacral laminectomy is preferred, although in selected cases it is possible to perform a supplemental anterior approach (sometimes endoscopic). In our surgical series, the largest one published in the literature, a good clinical outcome was achieved in most patients with no cyst's recurrence, pointing out the importance of surgical interruption of communication between cyst and subdural space.

Review/Perspective On the Diagnosis and Surgical Management of Spinal Arachnoid Cysts

Background:

Spinal arachnoid cysts (SAC) are typically congenital, spontaneous, traumatic (i.e., including iatrogenic/surgical), or inflammatory in origin. In descending order, they occur in the thoracic, lumbar, and cervical spine, and originate from focal entrapment of the arachnoid membrane. Arachnoid cysts represent 1–2% of all cystic spinal masses/tumors. The majority are extradural arachnoid cysts (EDAC) while 10% of all arachnoid cysts are intradural (IDAC) including subarachnoid, or extra-arachnoidal/subdural. Only rarely are they intramedullary in location. The clinical symptoms/signs of IDAC/EDAC include; intracranial hypotension (i.e., due to continued cerebrospinal fluid drainage), radiculopathy, and/or myelopathy.

Methods:

Magnetic Resonance Images (MR) and Myelo-Computed Tomography (Myelo-CT) studies classically document the predominant dorsal location of IDAC/EDAC. They also show their extent and severity contributing to root, cord, and/or cauda equina compression. In the cervical/thoracic spine, MR/Myelo-CT studies classically show the “double cord” or “windsock” signs, while the “fake arachnoiditis sign” may be seen in the lumbar spine. The latter sign signals the presence of a circumferential extra-arachnoidal-subdural cyst that centrally “traps” the cauda equina. Note, that this resembles and is often misinterpreted as adhesive archnoiditis.

Results:

Patients with significant SAC-related neurological deficits typically warrant early surgery. That surgery includes; partial/total resection/fenestration of cyst walls, and occlusion of communicating fistulas with or without accompanying shunts.

Conclusion:

It is critical to recognize the clinical (i.e., intracranial hypotension, radiculopathy, and/or myelopathy) and radiographic MR/Myelo-CT signs (i.e., “double cord,” “windsock signs”, or “fake arachnoiditis sign”) of IDAC, EDAC, or intramedullary spinal arachnoid cysts to appropriately offer treatment. For those with significant neurological deficits, early surgery (i.e. optimally 0-< 24 hours after the onset of symptoms/signs consisting of laminectomies, partial/total cyst resection/fenestration, and ligation/occlusion of the subarachnoid-cyst fistula with or without shunt placement), is essential to avoid significant permanent neurological sequelae.

Clinical Profile and Treatment Outcome of Spinal Epidural Arachnoid Cysts: A Systematic Review of Case Studies and Reports

Background A spinal epidural arachnoid cyst (SEAC) is a rare clinical entity. We performed a systematic review of the literature to obtain information regarding demographics, clinical presentation, treatment modalities, and outcome of SEACs.

Methods A literature search was performed by using the databases PubMed/Medline, PubMed Central, Embase, Cochrane Library, Ovid MEDLINE, and Ovid Medline In-Process. A total of 170 articles were found on literature search. We found 575 cases of SEAC since 1904 for inclusion in the review including three cases which were operated by us. We studied the patient characteristics, clinical features, and management strategies, and evaluated their outcome.

Results The average age of presentation was 30 years with a male:female ratio of 1.03:1. They are commonly seen in the thoracic region (42.3%). The length of cyst was more than two vertebral levels in 85.81%. Mean symptom duration was 29 months, with most common presentation being that of compressive myelopathy. A good clinical outcome was present in symptomatic patients who had a shorter symptom duration and underwent complete surgical excision of the SEAC. Age, sex, length of lesion, and presence of dural defect did not have a bearing on the surgical outcome.

Conclusion For thoracic compressive myelopathy in a young patient, SEAC should be kept as a differential diagnosis. Surgical complete excision of the cyst with meticulous closure of the dural defect is the standard in management for a good clinical outcome.

Congenital Spinal Cysts: An Update and Review of the Literature

Congenital spinal cysts are rare and encompass a wide variety of diseases including arachnoid, enterogenous, teratomatous, neurenteric, foregut, bronchogenic, epithelial, ependymal, dermoid, and epidermoid cysts. Here, we elucidate the epidemiology, pathology, pathogenesis, and diagnostic findings of the most common congenital spinal cysts, followed by a discussion of their presentation and treatment options. Differentiating the cause of each lesion is crucial for targeted clinical and surgical management for the patient. Our review describes how arachnoid cysts can be observed, fenestrated, percutaneously drained, or shunted; however, the primary goal for neurenteric, dermoid, and epidermoid cysts is removal. Further, we discuss how patient presentation is dependent on the rate of growth and location of compression on the spinal cord and nerve roots. However, although many of these lesions are discovered incidentally on imaging, the spectrum of possible symptoms include pain, weakness, ataxia, bladder incontinence, and progressive or acute neurologic deficits. We present and review the histology and imaging of a variety of cysts and discuss how although the goal of treatment is resection, the risks of surgery must be considered against the benefits of complete resection in each case.

Historical Perspective of Split Cord Malformations: A Tale of Two Cords

INTRODUCTION

Our appreciation and understanding of what is now known as the split cord malformation (SCM) have a long history. The oldest known example of SCM is from roughly AD 100. Other isolated examples can be found in the large body of work of the pathologists of the 1800s, where the SCMs were found incidentally during autopsies.

CONCLUSIONS

SCM has a rich history and has intrigued physicians for over 200 years. Many well-known figures from the past such as Chiari and von Recklinghausen, both pathologists, made early postmortem descriptions of SCM. With the advent of MRI, these pathological embryological derailments can now often be detected and appreciated early and during life. Our understanding and ability to treat these congenital malformations as well as the terminology used to describe them have changed over the last several decades.