Clinical analysis of syringomyelia resulting from spinal hemangioblastoma in a single series of 38 consecutive patients

Long-term outcome and prognostic factors of syringo-subarachnoid shunt for syringomyelia

BACKGROUND

Syringo-subarachnoid shunt (SSS) is often considered a rescue procedure or a second-line treatment option for syringomyelia. However, the clinical efficacy of SSS in treating this condition remains controversial.

OBJECTIVE

To evaluate the long-term outcome of the SSS and its relationship with the syrinx area, as well as to investigate the factors that influence the prognosis.

METHODS

This retrospective study included twenty-seven consecutive patients who underwent SSS between 2014 and 2020. The study evaluated several independent variables such as age, sex, duration of progressive symptoms, morphological characteristics of the syrinx, changes in the syrinx area, and Chiari malformation. The long-term follow-up (>2 years) Japanese Orthopaedic Association (JOA) score was used to assess neurological function and outcome. Statistical analysis was performed using a stepwise logistic regression test.

RESULTS

All patients were followed up for an average of 48.6 ± 14.8(26.8 to 78.0) months. Follow-up magnetic resonance imaging showed syrinx collapse to different degrees occurred in 96.3% (26 of 27) patients. The JOA score was improvedinonly6patients (22.2%), remained stable in 5 patients (18.5%),and deteriorated in 16 patients(59.3%).A logistic regression test showed that the tension syrinx (odds ratio 0.111) and early shunting intervention (odds ratio 0.138) were favorable independent prognostic factors.

CONCLUSIONS

It is important to note that the shrinkage of the syrinx does not necessarily translate to an improvement in clinical outcomes. Therefore, the decision to perform SSS should be made with caution and considered as a last resort.

Hemangioblastomas and Other Vascular Origating Tumors of Brain or Spinal Cord

Hemangioblastomas (HBs) are highly vascularized, slow-growing, rare benign tumors (WHO grade I). They account for about 2% of intracranial neoplasms; however, they are the most common primary cerebellar tumors in adults. Another frequent seat is the spinal cord (2-10% of primary spinal cord tumors). HBs are constituted by stromal and capillary vascular cells; macroscopically, HBs appear as nodular tumors, with or without cystic components. Although most of the HBs are sporadic (57-75%), they represent a particular component of von Hippel-Lindau disease (VHL), an autosomal dominant syndrome with high penetrance, due to a germline pathogenic mutation in the VHL gene, which is a tumor suppressor with chromosomal location on the short arm of chromosome three. VHL disease determines a variety of malignant and benign tumors, most frequently HBs, renal cell carcinomas, pheochromocytomas/paragangliomas, pancreatic neuroendocrine tumors, and endolymphatic sac tumors. Up to 20% of cases are due to de novo pathogenic variants without a family history. Many epidemiologic details of these tumors, especially the sporadic forms, are not well known. The median age of patients with sporadic HBS is about 40 years. More than two-third of VHL patients develop one or more central nervous system HBs during their lifetime; in case of VHL, patients at first diagnosis are usually younger than the patients with sporadic tumors. The most common presenting signs and symptoms are related to increased intracranial pressure, cerebellar signs, or spinal cord alterations in case of spinal involvement. Magnetic resonance imaging is the gold standard for the diagnosis, assessment, and follow-up of HBs, both sporadic and syndrome-related; angiography is rarely performed because the diagnosis is easily obtained with magnetic resonance. However, the diagnosis of an asymptomatic lesion does not automatically result in therapeutic actions, as the risks of treatment and the onset of possible neurological deficit need to be balanced, considering that HBs may remain asymptomatic and have a static or slow-growing behavior. In such cases, regular follow-up can represent a valid therapeutic option until the patients remain asymptomatic. There are no actual pharmacological therapies that are demonstrated to be effective for HBs. Surgery represents the primary therapeutic approach for these tumors. Observation or radiotherapy also plays a role in the long-term management of patients harboring HBs, especially in VHL; in few selected cases, endovascular treatment has been suggested before surgical removal. This chapter presents a systematic overview of epidemiology, clinical appearance, histopathological and neuroradiological characteristics of central nervous system HBs. Moreover, the genetic and molecular biology of sporadic and VHL HBS deserves special attention. Furthermore, we will describe all the available therapeutic options, along with the follow-up management. Finally, we will briefly report other vascular originating tumors as hemangioendotheliomas, hemangiomas, or angiosarcomas.

Chronological Progression and Management of Syringobulbia Caused by Spinal Hemangioblastoma: A Case Series and Review of the Literature

BACKGROUND

Syringomyelia often accompanies spinal hemangioblastoma (SHB). It often shows progression to the medulla oblongata, dubbed as "syringobulbia", which presents critical symptoms such as dysphagia and respiratory compromise. Appropriate management of chronological syringomyelia progression toward syringobulbia is not set in stone. This study aims to unravel the clinical and chronological behavior of syringobulbia and its management.

METHODS

A single-institution case series study of 5 patients operated for SHB with syringobulbia was conducted. Serial preoperative magnetic resonance imaging scans were analyzed in further details, especially focusing on the chronological progression of syringomyelia. A literature review was performed to describe clinical/imaging characteristics.

RESULTS

Chronological imaging analyses revealed that despite the relatively steady progression of syringomyelia over years, it accelerated when developing syringobulbia. Intramedullary signal change ("presyringomyelia") was observed in the area where syringomyelia subsequently occurred. Literature review yielded another 15 cases of SHB with syringobulbia, totaling 20 cases. Bulbar dysfunction was seen in 4 cases (20%). Gross total resection was performed in all cases except 1, which underwent just syringotomy. Rapid postoperative symptom improvement was observed in all cases, as well as immediate imaging resolution of syringomyelia.

CONCLUSIONS

The symptoms associated with syringobulbia often become life-threatening. Notably, its resolution may be near-synchronous to surgical resection of the spinal lesion. The speed of progression of syringomyelia is usually steady, but it may accelerate when extending to syringobulbia. Regular imaging follow-up is thus highly recommended to determine the best timing of intervention when presyringomyelia and syringomyelia are ascending toward the medulla oblongata.

Intramedullary Spinal Cord Lesions: A Single-Center Experience

Objective: Spinal cord tumors constitute a small part of spinal surgery owing to their rarity. This retrospective study describes their current management.Methods: Forty-eight patients were treated for an intramedullary tumor between 2014 and 2020 at a single institution. Patients’ files were retrospectively studied. We detailed clinical status according to neurological deficit and ambulatory ability using the modified McCormick Scale, radiological features like number of levels, associated syringomyelia, surgical technique with or without intraoperative electrophysiological monitoring, pathological findings, and postoperative outcome.Results: The median age of this population was 43 years, including 5 patients under 18 years. The median delay before first neurosurgical contact was 3 months after the first clinical complaint. Treatment was gross total resection in 43.8%, subtotal resection in 50.0%, and biopsy in 6.2%. A laminectomy was performed for all the patients except 2 operated using the laminoplasty technique. Pathological findings were ependymoma in 43.8%, hemangioblastoma in 20.8%, and pilocytic astrocytoma in 10.4%. Six patients were reoperated for a tumor recurrence less than 2 years after the first surgical resection. One patient was reoperated for a postoperative cervical kyphosis.Conclusion: Intramedullary tumors are still a challenging disease and they are treated by various surgical techniques. They must be managed in a specialized center including a trained surgical, radiological, electrophysiological, and pathological team. Arthrodesis must be discussed before performing extensive laminectomy to avoid postoperative kyphosis.

Clinical Prediction Modeling in Intramedullary Spinal Tumor Surgery

Artificial intelligence is poised to influence various aspects of patient care, and neurosurgery is one of the most uprising fields where machine learning is being applied to provide surgeons with greater insight about the pathophysiology and prognosis of neurological conditions. This chapter provides a guide for clinicians on relevant aspects of machine learning and reviews selected application of these methods in intramedullary spinal cord tumors. The potential areas of application of machine learning extend far beyond the analyses of clinical data to include several areas of artificial intelligence, such as genomics and computer vision. Integration of various sources of data and application of advanced analytical approaches could improve risk assessment for intramedullary tumors.

A Shunt Method for the Treatment of Syringomyelia Secondary to Trauma and Tuberculous Meningitis

The pathogenesis and surgical treatment of syringomyelia (SM) secondary to trauma and tuberculous meningitis are not clear. We hypothesize that the main cause of SM is impaired cerebrospinal fluid circulation in the subarachnoid space due to spinal arachnoid adhesion induced by trauma or tuberculous meningitis. Using trans-segmental subarachnoid shuntsurgery, we re-established normal cerebrospinal fluid circulation in the subarachnoid space, which resolved the potential cause of SM formation. This study aimed to evaluate the efficacy of trans-segmental subarachnoid shunt surgery in the treatment of SM secondary to trauma or tuberculous meningitis. A total of 143 patients with SM after trauma and tuberculous meningitis were recruited between September 2014 and February 2017. Among these patients, 64 had posttraumatic SM, including 39 males and 25 females with an age range of 21–65 years and an average age of 40.02 years, and 79 patients had SM secondary to tuberculous meningitis, including 49 males and 30 females with an age range of 23–62 years and an average age of 44.95 years. All patients underwent trans-segmental subarachnoid shunt surgery and were subjected to magnetic resonance imaging (MRI) examination between 6 months and 1 year and between 2 and 2.5 years after surgery. Clinical efficacy was assessed by the Tator method. The main symptoms or signs were evaluated by improvement, stabilizationor aggravation of symptoms. Patients were followed-up twice, once at 6 months to 1 year after surgery and once at 2 to 2.5 years after surgery. A total of 143 patients were followed-up for the first time, among whom, the clinical symptoms were improved in 59 patients(41.26%), stable in 51 patients (35.66%) and aggravated in 36 patients (23.08%). MRI exaination showed that the spinal cord cavities completely disappeared in 27 patients (18.88%), shrank significantly in 71 patients (49.65%), did not change or shrink significantly in 32 patients (22.38%) and expanded in 13 patients (9.09%). A total of 122 patients were followed-up for the second time, and the clinical symptoms were improved in 69 patients (56.56%), stable in 25 patients (20.49%) and aggravated in 28 patients (22.95%). Compared to the condition in the first follow-up, 14 patients who were stable were improved, 5 patients who were aggravated were improved, and the symptoms did not change significantly among other patients. The imaging examination did not show any significant change compared to that of the first follow-up. We suggest that trauma or tuberculous meningitis can induce spinal arachnoid adhesion, leading to impaired cerebrospinal fluid circulation in the subarachnoid space, which then causes SM. Trans-segmental subarachnoid shunt surgery is a noninvasive, safe and effective treatment for SM secondary to trauma and tuberculous meningitis.

Spinal Hemangioblastomas and Neuropathic Pain

BACKGROUND

Spinal hemangioblastomas (SHs) are rare and benign tumors. Primary symptoms include pain, hypoesthesia, and neuropathic pain (NP). Clinical symptoms may be as a result of tumor mass effect, peritumoral effect, syrinx, or venous congestion. No studies have focused on NP in SHs. The objective of this study was to review the rate and causes of NP in patients with SHs.

METHODS

The present study comprises a retrospective analysis of 13 patients with spinal hemangioblastomas. For the retrospective analysis of the patients, we analyzed the absence or presence of NP in the pre- and postoperative periods and its relationship with the level, location, and size of the tumor, as well as the size and location of the syrinx.

RESULTS

Postoperative NP was detected in 6 out of 13 patients. All 6 patients' tumors were located at the dorsal aspect of the spinal cord. There was a predominance of rostral syrinx location in patients with NP. Tumor size and level and syrinx size and level were not found to affect the occurrence of NP.

CONCLUSIONS

The present study shows that NP is observable in both pre- and postoperative periods. Proximity of the tumor to the dorsal root entry zone, and especially the presence of rostral syrinx, are the main factors affecting postoperative NP symptomatology. It is concluded that the combination of these factors and iatrogenic injury of anatomic pathways of NP within the spinal cord are responsible for postoperative NP.

Intramedullary Masses of the Spinal Cord: Radiologic-Pathologic Correlation

Spinal cord tumors are a challenge for patients and neurosurgeons because of the high risk of neurologic deficits from the disease process and surgical interventions. Spinal cord tumors are uncommon, and approximately 2%-3% of primary intra-axial tumors of the central nervous system occur in the spinal cord. Primary intra-axial tumors are usually derived from neuroepithelial tissue, especially glial cells. This often leads to a classic intramedullary mass differential diagnosis of ependymoma or astrocytoma, which together constitute up to 70% of spinal cord tumors. For example, ependymomas occur predominantly in adults, and astrocytomas (specifically pilocytic astrocytomas) occur predominantly in children. While that is an excellent starting point, in order to refine the differential diagnosis, the authors review the radiologic-pathologic features of specific neoplastic categories and entities recognized by the World Health Organization (WHO) in the 2016 WHO Classification of Tumours of the Central Nervous System and a few additional congenital-developmental entities. Radiologists can add value by providing a reasonable preoperative differential diagnosis for the patient and neurosurgeon, in many cases by favoring the most common conditions, and in other cases by identifying radiologic features that may point toward a less common entity. Some of the less common entities include intramedullary myxopapillary ependymoma, spinal subependymoma, and spinal hemangioblastoma. Whenever possible, the characteristic imaging features and locations of these tumors are explained or traced back to the underlying cell of origin and findings seen at histopathologic examination.See discussion on this article by Buch.