Long-term outcomes following surgical treatment of spinal arachnoid cysts: a population-based consecutive cohort study

BACKGROUND CONTEXT

Spinal arachnoid cysts (SACs) are rare, cerebrospinal fluid-filled sacs lined by an arachnoid membrane in the spinal canal. Symptoms can develop due to pressure on the spinal cord or adjacent spinal nerves by the cyst itself or by interrupted flow of cerebrospinal fluid. If noninvasive management fails or neurological deterioration occurs, surgical treatment is recommended. However, data is lacking on long-term outcomes after surgery.

PURPOSE

To determine long-term outcomes in patients surgically treated for SACs.

STUDY DESIGN

Population-based cohort-study.

PATIENT SAMPLE

All consecutive patients treated for either intra- or extradural SACs with surgery between 2005 and 2020 at the author's institution were included.

OUTCOME MEASURES

American Spinal Injury Association Impairment Scale (AIS) and modified Japanese Orthopedic Association score (mJOA).

METHODS

Data was primarily extracted from electronic patient medical notes. Telephone interviews were performed to assess long-term postoperative outcomes. All analyses were conducted using the statistical software program R version 4.0.5. Statistical significance was set at p<.05.

RESULTS

Thirty-four patients were included. Cyst excision was performed in 11 (32%) cases, and fenestration in the remaining 23 (68%). The median follow-up time was 8.0 years. Surgery resulted in a significant long-term improvement in both AIS (p=.012) and mJOA (p=.005). Sensory deficit was the symptom that most often improved (81%), followed by pain (74%) and motor function (64%). AIS deteriorated in two patients, of which one case was attributed to a surgical complication. Local cyst recurrence requiring reoperation was seen in 4 (12%) cases, all of them following cyst fenestration. One patient (3%) required reoperation for progression of the cyst progression at a different level.

CONCLUSION

This study reports outcomes of surgically treated SACs with the longest follow-up time to date. Microsurgical cyst excision or fenestration were safe treatment options, and the neurological improvements seen in the immediate postoperative phase were maintained at long-term follow-up.

Clinical and imaging features of spinal extradural arachnoid cysts: a retrospective study of 50 cases

PURPOSE

Spinal extradural arachnoid cysts (SEDACs) are thought to arise from leakage of CSF through a spinal dural defect. This study investigates the demographics and imaging spectrum of SEDACs at our academic institution and compares them with those reported in the literature.

METHODS

Fifty cases with documented MRI diagnosis of SEDAC, Nabors criteria type I meningeal cyst (MC), were identified from retrospective review of imaging records between 1999 and 2020. Patient demographics, presenting symptoms, cyst characteristics, and management outcomes were studied. Statistical analysis was performed to determine associations between maximum cyst size and presenting symptoms along with other imaging findings.

RESULTS

In all 50 subjects, SEDACs were solitary (single) and sporadic (non-familial). The majority were incidental (62%), located posteriorly (92%) and laterally (80%) in the thoracic and thoracolumbar regions (34%, 30%). They were associated with mild mass effect upon the thecal sac (50%) and bone remodeling (92%). Among symptomatic SEDACs, back pain and radiculopathy were the most reported (68%). Larger cysts were located caudally in the spinal canal, and were associated with greater thecal mass effect, bone remodeling, and septations. Four out of six subjects who underwent surgical management had complete or partial remission. One had cyst recurrence.

CONCLUSION

In this largest series of SEDACs, most were discovered incidentally, stable over time, and located in the thoracic spine dorsal to the thecal sac. When symptomatic, back pain and radiculopathy were the most common presenting symptoms. Treatment with complete surgical excision may yield the best results for symptomatic lesions.

Multiple extradural spinal arachnoid cysts: A case report

Background:

Extradural spinal arachnoid cysts (SACs) rarely cause neural compression and disability.

Case Description:

A 38-year-old female presented with a history of two episodes of falling due to transient weakness in the lower limbs. The neurological examination showed normal motor and sensory function, but hyperreflexia. The thoracic magnetic resonance imaging revealed multiple extradural SACs between the T3-L1 levels. Following complete surgical resection of the most symptomatic cyst, she did well. The histopathological examination confirmed a Type I extradural SAC.

Conclusion:

Here, we discussed one case and reviewed the literature on the diagnosis and treatment of multiple extradural SACs.

Intradiploic epidermoid cyst with intracranial hypertension syndrome: Report of two cases and literature review

INTRODUCTION

Intradiploic epidermoid intracranial cysts (IEIC) derive from ectodermal cells and are covered with stratified squamous epithelium. They are extremely rare, and most common locations are in the occipital, frontal and parietal bones. They have a very slow growth and can be asymptomatic until becoming evident by the deformation produced. The treatment is based on the removal of the lesion, and subsequent histopathological confirmation.

PRESENTATION OF CASE

Two cases are reported, with intracranial hypertension syndrome, which is very uncommon because of the slow growth of this type of pathology; however, decompensations occurring in the space-occupying lesions at intracranial level explain this type of clinical presentation.

DISCUSSION

The most common presentation of intracranial intradiploic epidermoid cysts (IEIC) is asymptomatically, which is made evident by the prominence at the level of the soft tissues and then presenting less frequently local pain and cephalea; rarely the size of the lesion can cause focal neurological signs.

CONCLUSION

These benign lesions, although they are of low incidence, are seen very rarely in intradiploic locations and above all, of significant size, may produce significant mass effect in patients, which was initially tolerated because of its slow growth, however, they may become decompensate and cause intracranial hypertension syndrome.