Multilayer Dura Reconstruction After Thoracoscopic Microdiscectomy: Technique and Results

Rotational Latissimus Dorsi Flap for Lateral Repair of Thoracic Cerebrospinal Fluid-Pleural Fistula: Case Report

BACKGROUND AND IMPORTANCE

Giant calcified thoracic discs are challenging surgical pathologies that tend to be more centrally located and calcified. This complicates the removal process and potentiates the formation of dural defects, resulting in persistent cerebrospinal fluid (CSF) leaks and the formation of pleural fistulas. The typical intervention for this is CSF diversion through external ventricular drain or lumbar drain placement, followed by direct repair. However, if all these measures fail, subsequent salvage techniques have not been described previously.

CLINICAL PRESENTATION

A 45-year-old man with past medical history of obesity (body mass index: 58), hypertension, and type 2 diabetes mellitus presented to the emergency department with thoracic myelopathy symptoms. MR demonstrated a giant calcified thoracic discs at T7-T8 with severe spinal cord compression. Intraoperatively, the disc was found fused to the dura and removal caused a large ventrolateral dural dehiscence. CSF diversion and direct repair were attempted unsuccessfully, so a salvage procedure with a rotational pedicled latissimus dorsi flap was performed. The patient's latissimus dorsi was exposed and resected from attachments, maintaining thoracodorsal blood supply, while removing thoracodorsal innervation. The flap was then rotated into the previous corpectomy site. The dural defect was repaired with a sealant patch, overlayed with a parietal pleural flap and the latissimus dorsi flap. By the patient's last follow-up, he had full functional independence at home.

CONCLUSION

We present a surgical case highlighting the challenges of managing postoperative CSF-pleural fistula occurring after giant calcified thoracic disc removal and the successful use of a novel rotational latissimus dorsi flap to definitively repair the fistula after unsuccessful primary interventions.

Image-guided transthoracic transpedicular microdiscectomy for a giant thoracic disc herniation: patient series

BACKGROUND

This case series reports on five consecutive patients who underwent image-guided transpedicular transthoracic microdiscectomy. The authors retrospectively reviewed five patients who had undergone Stealth image-guided transpedicular transthoracic microdiscectomy between 2015 and 2021.

OBSERVATIONS

Image guidance with O-arm verified critical anatomical landmarks in the setting of large central calcified and/or soft tissue disc prolapse. This allowed limited rib head resection, pedicle removal, and corpectomy to give adequate access and not require interbody fusion. The authors performed a partial posterior corpectomy anterior to the affected disc prolapse and microsurgical delivery of the affected disc anteriorly into the corpectomy cave away from the thecal sac. Electronic and radiographic records were analyzed at their initial presentation and at follow-up. The median patient age was 51 years (range, 44-56 years), with 80% of the patients being males. Four of five patients had significant improvement of their presenting clinical symptoms. One patient had a complicated postoperative recovery with a pneumothorax and subsequent bilateral pneumonia requiring intensive care. Another patient developed delayed postoperative worsening of paraparesis.

LESSONS

The use of Stealth image guidance with O-arm for transthoracic microdiscectomy for complex calcified thoracic disc herniation is an effective operative technical adjunct to verify anatomical landmarks and limit the microsurgical procedure.

Thoracoscopic Microdiscectomy with Preservation of Rib and Costovertebral Joint

INTRODUCTION

Thoracic disc herniations (TDH) may cause major morbidity. While thoracoscopic microdiscectomy (TMD) is an excellent technique, postoperative band-like pain is an important drawback.

MATERIAL AND METHODS

We performed 181 consecutive TMDs (including 39 high-risk cases) with preservation of rib and costovertebral joint (CVJ). We shave a few mm of the rib, drill straight to target, and avoid opening the canal before the TDH is completely free and (in case of giant TDHs) internally debulked, creating initial decompression and limiting epidural venous oozing. Subsequently, we gently mobilize and remove the residual TDH while avoiding leverage.

RESULTS

Skin-to-skin time was <90' in 64, 90-120' in 48, >120' in 20, unknown in 10, and 162' mean in 39 high-risk procedures. Blood loss was <100 mL in 76, <250 mL in 48, and 537 mL mean in 39 high-risk procedures. The technique was successfully applied in all (including nine dural repairs) without a single conversion. We observed an increased neurological deficit in two (1.1%) and inadequate decompression in merely one (wrong level). Complications (mainly pulmonary) were few and managed conservatively, except for a segmental artery pseudoaneurysm treated endovascularly. We observed a substantial decrease in acute and chronic postoperative pain.

DISCUSSION

The technique is fast, straightforward, minimizes bone resection and blood loss, improves orientation, safely and effectively deals with any TDH, and prevents postoperative band-like pain as the CVJ is preserved.

CONCLUSION

We hope this technique will find broader acceptance among a new generation of spine surgeons to benefit patients suffering TDH-related myelopathy or merely intractable pain.

Anterior Dural Tear in Thoracic and Lumbar Spinal Fractures: Single-Center Experience with Coating Technique and Literature Review of the Available Strategies

Differently from the posterior, the anterior dural tears associated with spinal fractures are rarely reported and debated. We document our experience with a coating technique for repairing ventral dural lacerations, providing an associated literature review on the available strategies to seal off such dural defects. A PubMed search on watertight repair techniques of anterior dural lacerations focused on their association with spinal fractures was performed. Studies on animal or cadaveric models, on cervical spine, or based on seal/gelfoam or “not suturing” strategies were excluded. 10 studies were finally selected and our experience of three patients with thoracic/lumbar spinal fractures with associated ventral dural tear was integrated into the analysis of the surgical techniques. Among the described repair techniques for ventral dural lacerations a preference for primary suturing, mostly trans-dural, was noted (n = 6/10 papers). Other documented strategies were the plugging of the dural opening with a fat graft sutured to its margins, or stitched to the dura adjacent to the defect, and the closure of the dural tear with two patches, both trans-dural and epidural. Our coating techniques of the whole dural sac with the heterologous patch were revealed as safe and effective alternatives strategies, even when patch flaps wrapping nerve roots have to be cut and a fat graft has to be stitched in the patch respectively for sealing off antero-lateral and wide anterior dural tears. Compared to all the documented strategies for obtaining a watertight closure of an anterior dural laceration, the coating techniques revealed advantages of preserving neural structures, being adaptable to anterior and antero-lateral dural tears of any size.

Transdural Thoracic Disk Herniation with Longitudinal Slitlike Dural Defect Causing Intracranial Hypotension: Report of 2 Cases

BACKGROUND

Intracranial hypotension (IH) has a widely variable clinical and radiologic presentation. Secondary IH may be caused by degenerative spine disorders and in particular by thoracic disk herniations (TDHs).

METHODS

We present 2 patients with a transdural TDH, a secondary IH, and superficial siderosis in 1.

RESULTS

Case 1 presented with headache, cognitive decline, staggering gait, bilateral subdural effusions, cerebral sagging, an extradural spinal cerebrospinal fluid (CSF) collection suggesting secondary IH, and a calcified TDH at T9-T10. Case 2 presented with intermittent pain at the craniocervical junction provoked exclusively by specific physical activities, superficial siderosis mainly in the posterior fossa, an extradural spinal CSF collection, and a calcified TDH at T7-T8 yet no intracranial signs of IH. In both cases, using strict thoracoscopic technique, we removed a transdural TDH and reconstructed an underlying longitudinal slitlike dural defect with smooth lining. Follow-up magnetic resonance imaging scans confirmed a dramatically improved situation without residual extradural intraspinal CSF collection or signs of IH.

CONCLUSIONS

This paper adds to the evidence that some cases of IH and even superficial siderosis are caused by transdural erosion of a TDH that may be otherwise asymptomatic. The dura may degenerate due to chronic compression, and a longitudinal slitlike dural defect with smooth lining may develop, causing continuous (Case 1) or intermittent (Case 2) intraspinal CSF leakage. To the best of our knowledge, such dural defects closely resembling the ones observed in idiopathic spinal cord herniation have never been demonstrated on intraoperative endoscopic video in IH patients.

Complications Associated with Surgery for Thoracic Disc Herniation: A Systematic Review and Network Meta-Analysis

BACKGROUND

A systematic review and network meta-analysis (Prospero ID CRD42018106936) were performed.

OBJECTIVE

The selection of the appropriate surgical approach for the management of thoracic disc herniation (TDH) is often challenging because of the frequency and variability of the associated complications. We evaluated the safety of the surgical approaches for TDH by estimating the mortality (Q1) and morbidity (Q2), and frequency of the most common complications (Q3).

METHODS

We searched the medical literature for randomized controlled trials and observational studies reporting on the management of TDH. Postoperative complications were the outcome of interest. The absolute and relative risk estimates, along with the rank probability scores, were estimated for each approach, through a network meta-analysis. The results were read in the light of the quality of the available evidence.

RESULTS

Fifteen studies with a total of 1036 patients fulfilled our eligibility criteria. Three deaths were reported. The overall morbidity was as high as 29%, largely attributed to medical (21%; 95% confidence interval [CI], 10%-38%), surgical site (11%; 95% CI, 5%-22%), cerebrospinal fluid-related (8%; 95% CI, 3%-8%), and neurologic complications (5%; 95% CI, 1%-24%). The anterior and lateral approaches were associated with a higher risk for medical and surgical complications compared with the posterolateral approach.

CONCLUSIONS

Surgery for TDH is associated with minimal mortality but significant morbidity, with large variations among the available approaches. An understanding of the perioperative complications rates is important to develop complication avoidance strategies and to aid accurate patient-to-doctor communication.