The authors report on a 47-year-old woman with a symptomatic thoracic spinal arachnoid cyst (SAC) who underwent a novel procedure that involves direct puncture of the SAC to visualize, diagnose, and potentially treat these rare spinal lesions. The method described utilizes 3D fluoroscopy to gain access to the SAC, followed by injection of myelographic contrast into the cyst. A characteristic “jellyfish sign” was observed that represents the containment of the contrast within the superior aspect of the cyst and a clear block of cranial flow of contrast, resulting in an undulating pattern of movement of contrast within the cyst. Following balloon fenestration of the cyst, unimpeded flow of contrast was visualized cranially throughout the thoracic subarachnoid space. The patient was discharged the following day in good condition, and subsequently experienced 1 year free from symptoms. This is the first reported case of a successful direct puncture of an SAC with balloon fenestration, and the first noted real-time fluoroscopic “behavior” of CSF within an arachnoid cyst.
Ziev B. Moses, John H. Chi and Ram V. S. R. Chavali
Yoon-Hee Cha, John H. Chi and Nicholas M. Barbaro
✓ Spinal subdural hematomas (SDHs) are a rare cause of cord compression and typically occur in the setting of spinal instrumentation or coagulopathy. The authors report the first case of a spontaneous spinal SDH occurring in conjunction with low-molecular-weight heparin use in a patient with a history of spinal radiotherapy.
Case report, review of the literature, and management algorithm
John H. Chi, Geoffrey T. Manley and Dean Chou
Pregnancy is a recognized risk factor for quiescent vertebral hemangiomas becoming symptomatic; this usually occurs during the 3rd month of gestation. The natural history of these lesions is poorly understood, and treatment practices must consider the overall safety of the mother and fetus. The authors report a case of cervical vertebral hemangioma presenting during the 24th week of pregnancy and review the current literature.
A 26-year-old woman in her 24th week of pregnancy presented with upper-back pain and progressive spastic paresis in the legs. Neuroimaging studies revealed a diffuse C-7 vertebral body lesion with extradural extension and compression of the spinal cord consistent with a vertebral hemangioma. Successful decompression was accomplished, and the fetus experienced no adverse effects from the surgery.
In a review of the literature, 23 cases of pregnancy-related vertebral hemangioma dating back to 1927 were identified. Prepartum surgical decompression was performed in eight patients, postpartum surgery was performed in 12, and surgery was not performed in four. Overall, patients experienced excellent neurological recovery, regardless of the severity and duration of spastic paresis.
Observation should be considered for symptomatic patients at greater than 32 weeks gestation. Surgery should be considered for patients with severe neurological deficits at less than 32 weeks of gestation.
John H. Chi and Michael W. McDermott
Tuberculum sellae meningiomas are a classic tumor of the anterior fossa that present in patients with gradual visual deterioration secondary to optic apparatus compression. If untreated, complete blindness can occur. Treatment involves tumor removal and decompression of the optic chiasm via several operative approaches. Gross-total resection (Simpson Grade I or II) is the goal of treatment and can usually be accomplished safely. Special excision-related considerations include appreciation of arachnoid planes separating the tumor from neural tissue, adequate drilling of osseous elements for optimal exposure, and intraoperative preservation of the vascular supply to the optic apparatus. The authors reviewed their experience at the University of California, San Francisco, in cases of tuberculum sellae meningiomas treated between 1992 and 2002. In most patients, improvement of vision can be achieved with minimal postoperative complications and morbidity.
Yakov Gologorsky, John J. Knightly, John H. Chi and Michael W. Groff
The rates of lumbar spinal fusion operations have increased dramatically over the past 2 decades, and several studies based on administrative databases such as the Nationwide Inpatient Sample (NIS) have suggested that the greatest rise is in the general categories of degenerative disc disease and disc herniation, neither of which is a well-accepted indication for lumbar fusion. The administrative databases classify cases with the International Classification of Disease, Ninth Revision, Clinical Modification (ICD-9-CM). The ICD-9-CM discharge codes are not generated by surgeons but rather are assigned by trained hospital medical coders. It is unclear how accurately they capture the surgeon's indication for fusion. The authors sought to compare the ICD-9-CM code(s) assigned by the medical coder to the surgeon's indication based on a review of the medical chart.
A retrospective review was undertaken of all lumbar fusions performed at our institution by the department of neurosurgery between 8/1/2011 and 8/31/2013. Based on the authors' review, the indication for fusion for each case was categorized as spondylolisthesis, deformity, tumor, infection, nonpathological fracture, pseudarthrosis, adjacent-level degeneration, stenosis, degenerative disc pathology, or disc herniation. These surgeon diagnoses were compared with the primary ICD-9-CM codes that were submitted to administrative databases.
There were 178 lumbar fusion operations performed for 170 hospital admissions. There were 44 hospitalizations in which fusion was performed for tumor, infection, or nonpathological fracture; the remaining 126 were for degenerative diagnoses. For these degenerative cases, the primary ICD-9-CM diagnosis matched the surgeon's diagnosis in only 61 of 126 degenerative cases (48.4%). When both the primary and all secondary ICD-9-CM diagnoses were considered, the indication for fusion was identified in 100 of 126 cases (79.4%).
Characterizing indications for fusion based solely on primary ICD-9-CM codes extracted from large administrative databases does not accurately reflect the surgeon's indication. While these databases may accurately describe national rates of lumbar fusion surgery, the lack of fidelity in the source codes limits their role in accurately identifying indications for surgery. Studying relationships among indications, complications, and outcomes stratified solely by ICD-9-CM codes is not well founded.
Viren S. Vasudeva, John H. Chi and Michael W. Groff
Vertebral hemangiomas are common tumors that are benign and generally asymptomatic. Occasionally these lesions can exhibit aggressive features such as bony expansion and erosion into the epidural space resulting in neurological symptoms. Surgery is often recommended in these cases, especially if symptoms are severe or rapidly progressive. Some surgeons perform decompression alone, others perform gross-total resection, while others perform en bloc resection. Radiation, embolization, vertebroplasty, and ethanol injection have also been used in combination with surgery. Despite the variety of available treatment options, the optimal management strategy is unclear because aggressive vertebral hemangiomas are uncommon lesions, making it difficult to perform large trials. For this reason, the authors chose instead to report their institutional experience along with a comprehensive review of the literature.
A departmental database was searched for patients with a pathological diagnosis of “hemangioma” between 2008 and 2015. Medical records were reviewed to identify patients with aggressive vertebral hemangiomas, and these cases were reviewed in detail.
Five patients were identified who underwent surgery for treatment of aggressive vertebral hemangiomas during the specified time period. There were 2 lumbar and 3 thoracic lesions. One patient underwent en bloc spondylectomy, 2 patients had piecemeal gross-total resection, and the remaining 2 had subtotal tumor resection. Intraoperative vertebroplasty was used in 3 cases to augment the anterior column or to obliterate residual tumor. Adjuvant radiation was used in 1 case where there was residual tumor as well. The patient who underwent en bloc spondylectomy experienced several postoperative complications requiring additional medical care and reoperation. At an average follow-up of 31 months (range 3–65 months), no patient had any recurrence of disease and all were clinically asymptomatic, except the patient who underwent en bloc resection who continued to have back pain.
Gross-total resection or subtotal resection in combination with vertebroplasty or adjuvant radiation therapy to treat residual tumor seems sufficient in the treatment of aggressive vertebral hemangiomas. En bloc resection appears to provide a similar oncological benefit, but it carries higher morbidity to the patient.
John H. Chi, Heather J. Fullerton and Nalin Gupta
Congenital hydrocephalus has an estimated population incidence of 0.2 to 0.8/1000 live births. With improvements in techniques for cerebrospinal fluid shunting, treatment of hydrocephalus has become safe and routine, yet data describing mortality from congenital hydrocephalus or demonstrating improvements in mortality with the advent of modern treatment are scarce. The authors' analysis sought to rectify this situation.
The authors performed an electronic search of National Center for Health Statistics death certificate databases to identify deaths from 1979 to 1998 attributed to congenital hydrocephalus, spina bifida with hydrocephalus, and acquired hydrocephalus (both obstructive and communicating) in all children in the US aged 1 day to 20 years. Mortality rates were defined as deaths per 100,000 person-years and were analyzed for differences on the basis of age, race, sex, and year.
The authors identified 10,406 deaths attributed to childhood hydrocephalus within the 20-year study period. The overall mortality rate was 0.71 per 100,00 person-years. Mortality rates were highest in infants, with 3979 deaths; they were similar between girls and boys. Compared with white infants, black infants had higher relative risk (RR) for death caused by congenital hydrocephalus (RR 1.46, p value < 0.0001) and acquired hydrocephalus (RR 2.58, p value < 0.0001) but not for that caused by hydrocephalus with spina bifida (RR 0.65, p value < 0.0001). From 1979 to 1998, the mortality rate due to congenital hydrocephalus declined 66.3%, from spina bifida with hydrocephalus it declined by 30.4%, and from acquired hydrocephalus it declined by 67.5%.
Mortality rates from childhood hydrocephalus have declined in US children over the previous 20 years. Black race is associated with higher mortality rates in infants for both congenital and acquired hydrocephalus, whereas sex has no effect.
John H. Chi, Sanjay S. Dhall, Adam S. Kanter and Praveen V. Mummaneni
Thoracic disc herniations can be surgically treated with a number of different techniques and approaches. However, surgical outcomes comparing the various techniques are rarely reported in the literature. The authors describe a minimally invasive technique to approach thoracic disc herniations via a transpedicular route with the use of tubular retractors and microscope visualization. This technique provides a safe method to identify the thoracic disc space and perform a decompression with minimal paraspinal soft tissue disruption. The authors compare the results of this approach with clinical results after open transpedicular discectomy.
The authors performed a retrospective cohort study comparing results in 11 patients with symptomatic thoracic disc herniations treated with either open posterolateral (4 patients) or mini-open transpedicular discectomy (7 patients). Hospital stay, blood loss, modified Prolo score, and Frankel score were used as outcome variables.
Patients who underwent mini-open transpedicular discectomy had less blood loss and showed greater improvement in modified Prolo scores (p = 0.024 and p = 0.05, respectively) than those who underwent open transpedicular discectomy at the time of early follow-up within 1 year of surgery. However, at an average of 18 months of follow-up, the Prolo score difference between the 2 surgical groups was not statistically significant. There were no major or minor surgical complications in the patients who received the minimally invasive technique.
The mini-open transpedicular discectomy for thoracic disc herniations results in better modified Prolo scores at early postoperative intervals and less blood loss during surgery than open posterolateral discectomy. The authors' technique is described in detail and an intraoperative video is provided.
Ziev B. Moses, Gabriel N. Friedman, David L. Penn, Isaac H. Solomon and John H. Chi
Optimal diagnosis and management strategies for intradural spinal arachnoid cysts (SACs) are still unresolved given the rare nature of this entity, with few large case series and virtually no statistical analyses of patient characteristics in the literature. Here, the authors studied a large patient cohort with these lesions to determine whether pre- or postoperative attributes could be used to aid in either diagnosis or prognosis.
A chart review was completed at a single institution for the period from 2002 to 2016 to determine the preoperative characteristics and postoperative outcomes of 21 patients with exclusively intradural SACs. Patients were assessed for symptoms such as weakness, pain, sensory changes, bowel and/or bladder dysfunction, and gait changes. Postoperatively, patients were analyzed for symptom improvement, complication occurrence, and duration of follow-up.
Approximately two-thirds of the patients in this series had developed SACs idiopathically, and the mean duration of symptoms prior to diagnosis was 15 months among all patients. A slight majority (57%) underwent CT myelography in the course of diagnosis, and a quarter of the patients had a syrinx. There was a statistically significant association between location of the SAC and number of presenting signs and symptoms; that is, patients with cysts in the lumbosacral region had more symptoms than those with cysts at the cervical or thoracic levels (p = 0.031). Overall, outcomes were largely positive, with approximately 60%–70% of patients experiencing postoperative improvement in symptoms, with motor weakness showing the highest response rate (71%) and pain symptoms the least likely to subside (50%). In the cohort with preoperative pain, those who had undergone expansile duraplasty were significantly more likely to experience relief of their pain symptoms (p = 0.028), which may have been a result of the superior restoration of cerebrospinal fluid pathways allowing for more adequate reduction in compression.
In this large case series on intradural SACs, new light has been shed on aspects of both pre- and postoperative care for patients with these rare lesions. Specifically, the authors revealed that lumbosacral intradural SACs may be associated with a higher disease burden and that patients who undergo expansile duraplasty may have an increased likelihood of experiencing postoperative pain relief.