Extradural Spinal Cord Compression Research Articles

LMIC-21. SERIES OF 9 CASES OF SPINAL CORD COMPRESSION IN CHILDREN: A SINGLE EXPERIENCE FROM THE PEDIATRIC NEURO-ONCOLOGY GROUP, IN A MIDDLE INCOME COUNTRIES

Abstract BACKGROUND Spinal cord compression secondary to pediatric neoplasms is a rare but serious event that can result in irreversible neurological sequelae, with paralysis, sensory losses and sphincter dysfunction. This retrospective study aims to describe the main causes, treatments and outcomes of a series of cases of spinal cord compression in patients admitted to the Childhood Cancer Treatment Institute- ITACI, University of São Paulo, Brazil. METHODS Based on data collected from the pediatric neuro oncology group, we analyzed nine cases of spinal cord compression in patients under 18 years, admitted from 2020 to 2023. RESULTS In our case series, 7 of the 9 children were female, with an average age of 104 months, the youngest being 3 months. Of the cases described, 77.7% had extradural spinal cord compression. Ewing’s sarcoma was the main neoplasm associated with extradural compression, representing 44.4%. Neuroblastoma, giant cell tumor and B acute lymphoblastic leukemia accounted for 11.1% of cases each. Cases of intradural compression were represented by low-grade glioma with cervical compression and germ cell tumor from with thoracolumbar lesion. Spinal cord compression was the first manifestation of malignancy in 8 of the 9 patients, who presented loss of motricity and sensitivity. All patients were treated with corticosteroid, therapy due to its benefits in reducing vasogenic edema caused by spinal cord compression. Additionally, 8 patients underwent surgical spinal decompression. A patient with Ewing sarcoma received cytoreductive chemotherapy and achieved complete motor recovery. CONCLUSIONS Spinal cord compression is associated with serious neurological sequelae when not treated appropriately. However, neurological recovery is possible with early diagnosis and adequate decompression treatment. We increased the importance of specialized services with a pediatric neuro-oncology group, in which several professionals work together to provide individualized care, even in developing countries, as demonstrated by the patients treated at our institution.

Computed tomography myelography description of pneumorrhachis secondary to a degenerative intervertebral disk disease in a cross‐breed dog

AbstractA 9‐year‐old, male, neutered, cross‐breed dog was presented for a 6‐month history of spinal pain, mild pelvic limbs proprioceptive ataxia and discrete ambulatory paraparesis. Computed tomography myelography identified focal gas accumulation in the left aspect of the vertebral canal at the level of T11–T12, resulting in moderate extradural spinal cord compression. Minor chronic intervertebral disk protrusion was also identified at this level with no evidence of spinal cord compression. An encapsulated space‐occupying gas accumulation was identified and removed during a left‐sided T11–T12 hemilaminectomy. On histopathological analysis, the capsule was formed by connective and inflammatory tissue. Early neurological deterioration following surgery was observed due to persistent extradural material causing spinal cord compression. Widening of the previous hemilaminectomy window was performed to remove the compressive material, and progressive improvement was noted during the following weeks. This is the first case of computed tomography myelography description of pneumorrhachis in a dog.

Evaluating the impact of the metastatic spinal cord compression coordinator in a regional cancer network: a prospective, non- randomized pilot study.

Extradural metastatic spinal cord compression (MSCC) is a debilitating and potentially irreversible complication of cancer. Delay in treatment could lead to irreversible neurological damage, adverse quality of life and a burden on health care resources. Lack of effective communication between teams has been identified as one of the reasons for delay in treatment. The MSCC coordinator (often a nurse, radiotherapy radiographer or a doctor) is responsible for coordinating the diagnosis and management of patients with MSCC. The role has been shown to streamline service, ensure timely decision-making and improved survival outcomes. However, available data are anecdotal or from limited series presented as abstracts in conferences. In this study, we assessed the impact (time to treatment) of the newly introduced role on the treatment pathway compared to similar period in the preceding year. This was a multi-centre, prospective, pilot study carried out in Kent, UK between 1st April to 30th June 2021. Patients were considered eligible if they had MRI-confirmed cauda equina or cord compression. The data prospectively collected include: (I) time from diagnostic imaging to radiotherapy treatment; (II) number of referrals to hospital palliative care (HPC), occupational/physiotherapy (OPH) and community hospice referrals (CHP). A comparative retrospective data for (I) was collected for the same time period in the preceding year. The study outcome assessed was reduction in time from radiological diagnosis of MSCC to receiving radiotherapy. Fifty-eight patients in 2020 and 24 patients in 2021 were included in the dataset. The MSCC coordinator role (introduced in 2021) led to reduction in the time from imaging to treatment (P=0.045). Compared to 2020, there was a shorter mean/median time to treatment, seeing more patients being treated within 24 hours. All hospitals except East Kent Hospitals saw more patients being treated within 24 hours. 7 referrals each made to HPC, OPH and CHP respectively. Introduction of MSCC coordinator role led to improved time from imaging to radiotherapy treatment. The new service led to engagement with rehabilitative and palliative services. Future work should be done to assess the long-term impact of this role on utilization of support services and patient recovery.

Extradural Synovial Cyst of the Cervical Spine in a Saint Bernard

Background: Extradural synovial cysts (ESC) originate from an extrusion of the synovium in unstable or degenerated joints. In the spine, this condition can cause neurological signs such as hyperesthesia, proprioceptive ataxia and paresis. Since extradural presentations of synovial cysts are unusual in dogs, the aim of this manuscript is to report a case of extradural synovial cyst of the cervical spine, as well as the clinical findings, diagnosis, surgical treatment and clinical evolution after therapy.Case: A 3-year-old spayed Saint Bernard weighing 60 kg was presented to a Veterinary Medical Teaching Hospital with a history of acute paraparesis that evolved to non-ambulatory tetraparesis five days after the appearance of the first clinical signs. Neurological examination revealed non-ambulatory tetraparesis, normal muscle tone and segmental spinal reflexes in the thoracic and pelvic limbs, as well as cervical pain associated with limited neck movement. According to the neurological examination, the likely lesion location was the C1-C5 spinal cord segment. The differential diagnosis list included intervertebral disc disease, caudal cervical spondylomyelopathy, neoplasm, infectious or noninfectious inflammatory disease, and cystic diseases. Complete blood (cell) count and serum biochemistry tests were within reference limits. The cerebrospinal fluid analysis revealed 35 mg/dL of protein (< 30 mg/dL) and 27 cells (up to 5 cells/mm3) with a predominance of lymphocytes. In plain radiography, bone proliferations of the C4 (caudal) C5 (cranial) articular processes were observed and, in myelography, extradural spinal cord compression was evident between C4-C5 on the right side. The animal underwent dorsal laminectomy for spinal cord decompression. An extradural synovial cyst and proliferated articular processes were removed. At 1,281 days after surgery, the dog was clinically normal and presented no neurological deficits.Discussion: The etiology of synovial cysts has not been well established. However, it is believed that osteoarthritic degeneration associated with joint mobility could cause a rupture in the articular capsule, leading to a synovial membrane protrusion, which would fill with synovial fluid and compress spinal structures. ESC in the cervical region have been reported, often associated with cervical neoplasm. The case we report had no evidence of bone or intervertebral disc compression in myelographic and radiographic exams, abnormalities that would appear in cervical neoplasm. The patient underwent dorsal laminectomy to confirm the presumptive diagnosis and decompress the spine. In the histopathological exam, the cystic material consisted of connective fibrous tissue with a synovial cell lining layer, compatible with synovial cysts. The fluid drained during surgery was also analyzed, showing similarities to synovial fluid drained from other conventional joints. Cerebrospinal fluid analysis revealed mononuclear pleocytosis, a common finding in ESC. The ESC should be included in the differential diagnosis of dogs with cervical myelopathy, especially in young animals and large breeds. A myelographic exam is an important but not definitive auxiliary tool for diagnosis and the therapeutic plan. Dorsal laminectomy is an effective technique for treating ESC.

Surgical and Radiotherapeutic Management of Malignant Extradural Spinal Cord Compression

Malignant spinal cord compression is one of the most dreaded complications of advanced malignancy, with patients presenting with progressive paralysis, paresthesia and/or autonomic dysfunction. The choice of management should be guided by the expected prognosis and outcome, not just from a neurological function point-of-view but also from the metastatic cancer itself. The main indications for surgery are: impending cord compression, spinal instability from tumour progression, bony retropulsion, for tissue diagnosis and for pain resistant to conventional therapies. Here, surgical principles, traditional and novel techniques and complications will be reviewed. For radiotherapy, multiple randomised studies have shown that for most patients a single fraction of external radiation has the same functional outcomes compared with multi-fractionation protocols. The experience of a specialised centralised interdisciplinary team will also be discussed.

Chronic extradural compression of spinal cord leads to syringomyelia in rat model

BackgroundSyringomyelia is a common spinal cord lesion. However, whether CSF blockage is linked to the formation and enlargement of syringomyelia is still controversial. The current model of syringomyelia needs modification to more closely mimic the clinical situation.MethodsWe placed cotton strips under the T13 lamina of 40 8-week-old rats and blocked CSF flow by extradural compression. After 4 and 8 weeks, MRI was performed to evaluate the morphology of syringomyelia and the ratio of spinal cord diameter to syrinx diameter calculated. Locomotor function was evaluated weekly. Spinal cord sections, staining and immunohistochemistry were performed 8 weeks after surgery, the ratio of the central canal to the spinal cord area was calculated, and ependymal cells were counted. In another experiment, we performed decompression surgery for 8 rats with induced syringomyelia at the 8th week after surgery. During the surgery, the cotton strip was completely removed without damaging the dura mater. Then, the rats received MRI imaging during the following weeks and were sacrificed for pathological examination at the end of the experiment.ResultsSyringomyelia formed in 82.5% (33/40) of rats at the 8-week follow-up. The Basso, Beattie and Bresnahan (BBB) scores of rats in the experimental group decreased from 21.0±0.0 to 18.0 ±3.9 in the first week after operation but returned to normal in later weeks. The BBB score indicated that the locomotor deficit caused by compression is temporary and can spontaneously recover. MRI showed that the syrinx is located in the center of the spinal cord, which is very similar to the most common syringomyelia in humans. The ratio of the central canal to the spinal cord area reached (2.9 ± 2.0) × 10−2, while that of the sham group was (5.4 ± 1.5) × 10−4. The number of ependymal cells lining the central canal was significantly increased (101.9 ± 39.6 vs 54.5 ± 3.4). There was no syrinx or proliferative inflammatory cells in the spinal cord parenchyma. After decompression, the syringomyelia size decreased in 50% (4/8) of the rats and increased in another 50% (4/8).ConclusionExtradural blockade of CSF flow can induce syringomyelia in rats. Temporary locomotor deficit occurred in some rats. This reproducible rat model of syringomyelia, which mimics syringomyelia in humans, can provide a good model for the study of disease mechanisms and therapies.

Quality Improvement Initiative to Enhance Multidisciplinary Management of Malignant Extradural Spinal Cord Compression.

To determine if a quality improvement (QI) initiative could enhance multidisciplinary management of acute malignant extradural spinal cord compression (ESCC) at our institution. The medical records of all 40 patients who received palliative radiotherapy for malignant ESCC from 2015 to 2017 were reviewed to determine the time course of key National Comprehensive Cancer Network guideline-supported workup and management steps. On the basis of the findings, a multidisciplinary group of physician stakeholders developed a clinical pathway to facilitate expedited care. The efficacy of this clinical pathway and the educational content provided to all relevant departments were then evaluated by comparing outcomes with data from a similarly reviewed follow-up cohort of 25 patients from 2018 to 2019. Patients treated for malignant ESCC after our QI intervention were more likely to undergo magnetic resonance imaging (MRI) of the entire spine (64% v 44%; P = .013) and have a radiation oncology (RO) consultation before surgery (100% v 27%; P = .002). Median time from MRI to RO consultation decreased from 3 to 1 days (P = .03). On subgroup analysis, initial trends toward delays in RO consultation for patients planning for surgery (median, 3 days) or for lack of prior cancer diagnosis (median, 4 days) were reduced to delays of 0 and 1 day, respectively, after the QI intervention. No significant differences were observed in time to surgical consultation or surgery itself. This QI study was able to stimulate better use of diagnostic imaging and earlier involvement of RO in multidisciplinary decision making, suggesting an effective approach to improving multidisciplinary care in other scenarios as well.

Initial presentation of Hodgkin’s Lymphoma as Extradural Spinal Cord Compression: A case report

A 23 year old female presented with acute onset paraparesis. She denied any history of fever, weight loss or drenching night sweats. Neither did she have any obvious lymphadenopathy on general examination. Chest Xray was however suggestive of mediastinal widening and her MRI spine showed metastases with superior mediastinal SOL. Biopsy of this SOL ultimately revealed classical Hodgkin lymphoma. Thus this was a very unusual initial presentation of Hodgkin lymphoma presenting as Epidural Spinal Cord Compression. Hasenclever IPS score was 2. Patient was treated with radiotherapy followed by ABVD chemotherapy and achieved remission in 3months.

Clinical, diagnostic imaging, surgical findings and long-term outcome in a Cavalier King Charles Spaniel with thoracolumbar vertebral articular process hyperplasia

A 2-year-old female spayed Cavalier King Charles Spaniel presented with 10-day history of progressive painful T3–L3 myelopathy. MRI of the spine revealed an extradural dorsal spinal cord compression at the...

Activation of A2A Receptor by PDRN Reduces Neuronal Damage and Stimulates WNT/β-CATENIN Driven Neurogenesis in Spinal Cord Injury.

Spinal cord injury (SCI) is a complex clinical and progressive condition characterized by neuronal loss, axonal destruction and demyelination. In the last few years, adenosine receptors have been studied as a target for many diseases, including neurodegenerative conditions. The aim of this study was to investigate the effects of an adenosine receptor agonist, PDRN, in an experimental model of SCI. Moreover, since adenosine receptors stimulation may also activate the Wnt pathway, we wanted to study PDRN effects on Wnt signaling following SCI. Spinal trauma was induced by extradural compression of spinal cord at T5-T8 level in C57BL6/J mice. Animals were randomly assigned to the following groups: Sham (n = 10), SCI (n = 14), SCI+PDRN (8 mg/kg/i.p.; n = 14), SCI+PDRN+DMPX (8 and 10 mg/kg/i.p., respectively; n = 14). DMPX was used as an adenosine receptor antagonist to evaluate whether adenosine receptor block might prevent PDRN effects. PDRN systemically administered 1 h following SCI, protected from tissue damage, demyelination, and reduced motor deficits evaluated after 10 days. PDRN also reduced the release of the pro-inflammatory cytokines TNF-α and IL-1β, reduced BAX expression and preserved Bcl-2. Furthermore, PDRN stimulated Wnt/β-catenin pathway and decreased apoptotic process 24 h following SCI, whereas DMPX administration prevented PDRN effects on Wnt/β-catenin signaling. These results confirm PDRN anti-inflammatory activity and demonstrate that a crosstalk between Wnt/β-catenin signaling is possible by adenosine receptors activation. Moreover, these data let us hypothesize that PDRN might promote neural repair through axonal regeneration and/or neurogenesis.

Neoplastic Myelopathies.

This article discusses the diagnosis and management of neoplasms that affect the spinal cord as well as spinal cord disorders that can occur due to cancer treatments. Neoplastic myelopathies are uncommon neurologic disorders but cause significant morbidity when they occur. Primary spinal cord tumors can be classified into intramedullary, intradural extramedullary, or extradural tumors. Diffuse gliomas and ependymal tumors are the most common intramedullary tumors. Diffuse gliomas include the World Health Organization (WHO) grade II and grade III astrocytomas, the grade II and grade III oligodendrogliomas, the grade IV glioblastomas, and newly recognized pediatric diffuse midline gliomas with H3 K27M mutation. The majority of diffuse and anaplastic astrocytomas are IDH-mutant tumors, whereas only 10% of glioblastomas are IDH-mutant. Oligodendrogliomas are typically IDH-mutant and are characterized by the molecular signature of 1p/19q codeletion. Nine distinct molecular subgroups of ependymomas have been identified based on their genetic features and location. NF2 mutations are frequently found in spinal cord ependymomas. Metastatic tumors are the most common tumors of the spine and can be extradural, leptomeningeal, or, rarely, intramedullary. Extradural metastatic spinal cord compression is a neurologic emergency and should be promptly diagnosed as pretreatment neurologic status dictates the posttreatment outcome. Neoplastic myelopathies encompass many diagnoses ranging from benign and malignant spinal tumors to paraneoplastic syndromes heralding cancers. The knowledge of the clinical features and management of neoplastic myelopathies is essential to practicing neurologists as early diagnosis and treatment can prevent devastating neurologic sequelae.

Extragonadal germ cell tumor of the posterior mediastinum in a child complicated with spinal cord compression: a case report

BackgroundGerm cell tumors (GCTs) in children are rare neoplasms with diverse pathological findings according to the site and age of presentation. The most common symptoms in children with mediastinal GCTs, which are nonspecific, are dyspnea, chest pain, cough, hemoptysis, vena cava occlusion syndrome, and fatigue/weakness. Because of these nonspecific symptoms, it is difficult to suspect a mediastinal mass. A posterior mediastinal tumor causing spinal cord compression is an important example of an oncologic emergency arising from a neurogenic tumor.Case presentationChildren with posterior mediastinum GCTs can be easily mistaken as having a neurogenic tumor because of site of tumor origin. We treated our 7-year-old patient with emergency decompression surgery and high-dose steroid pulse therapy to prevent secondary injury to the spinal cord. Primary injury was a result of spinal cord compression due to the initial manifestation of GCT in the posterior mediastinum. Cisplatin-based chemotherapy was also administered. The patient was followed up regularly for 3 years and is undergoing rehabilitation without any signs of recurrence.ConclusionsWe present an extremely rare case of a child with paraparesis caused by extradural spinal cord compression as the initial manifestation of GCT in the posterior mediastinum. The child was treated with emergency decompression surgery and high-dose pulse steroid therapy to prevent secondary injury to the spinal cord.

Free radical scavenger edaravone produces robust neuroprotection in a rat model of spinal cord injury

We used a multimodal approach to evaluate the effects of edaravone in a rat model of spinal cord injury (SCI). SCI was induced by extradural compression of thoracic spinal cord. In experiment 1, 30 min prior to compression, rats received a 3 mg/kg intravenous bolus of edaravone followed by a maintenance infusion of 1 (low-dose), 3 (moderate-dose), or 10 (high-dose) mg/kg/h edaravone. Although both moderate- and high-dose edaravone regimens promoted recovery of spinal motor-evoked potentials (MEPs) at 2 h post-SCI, the effect of the moderate dose was more pronounced. In experiment 2, moderate-dose edaravone was administered 30 min prior to compression, at the start of compression, or 10 min after decompression. Although both preemptive and coincident administration resulted in significantly improved spinal MEPs at 2 h post-SCI, the effect of preemptive administration was more pronounced. A moderate dose of edaravone resulted in significant attenuation of lipid peroxidation, as evidenced by lower concentrations of the free radical malonyldialdehyde in the spinal cord 3 h post-SCI. Malonyldialdehyde levels in the high-dose edaravone group were not reduced. Both moderate- and high-dose edaravone resulted in significant functional improvements, evidenced by better Basso-Beattie-Bresnahan (BBB) scores and better performance on an inclined plane during an 8 week period post-SCI. Both moderate- and high-dose edaravone significantly attenuated neuronal loss in the spinal cord at 8 weeks post-SCI, as evidenced by quantitative immunohistochemical analysis of NeuN-positive cells. In conclusion, early administration of a moderate dose of edaravone minimized the negative consequences of SCI and facilitated functional recovery.

Paraparesis secondary to erratic migration of Dioctophyma renale in a dog

ABSTRACT: A 4 years old mongrel stray bitch, weighing 16kg was submitted to physical examination to demonstrated inability of locomotion with the pelvic limbs. Extradural spinal cord compression was observed in myelotomography of the thoracolumbar segment. The patient was submitted to exploratory hemilaminectomy of T13-L1 and L1-L2, in an attempt to decompress the medullar segments. During the surgery was observed one adult parasite, identified as Dioctophyma renale , located in the extradural space and causing spinal cord compression. The patient was submitted to postoperative physical therapy, presenting clinical improvement 15 days after surgery, remaining on prone position and able to move the pelvic limbs, but not yet able to walk unassisted. It started walking naturally 60 days after the surgery. With the present clinical report, the erratic migration of the parasite Dioctophyma renale should be added to the list of differential diagnoses for patients with paraparesis and extramedullary lesion pattern, especially in endemic areas.

Interventions for the treatment of metastatic extradural spinal cord compression in adults.

Interventions for the treatment of metastatic extradural spinal cord compression in adults.

Computed tomographic myelography of a foal with discospondylitis and extradural spinal cord compression due to a vertebral abscess

SummaryA one‐month‐old Quarter Horse colt presented with progressive gait abnormalities and weakness. The foal was ataxic at presentation. Radiography identified focal endplate irregularities and lysis at C6–7. Radiographic diagnosis was discospondylitis. Computed tomographic myelography was performed immediately following euthanasia and identified an extradural compressive spinal cord lesion corresponding to the site of discospondylitis. Post mortem examination findings included abscess formation at the C6–7 intervertebral space with osteomyelitis extending into the adjacent physes and subchondral bone of caudal C6 and cranial C7. The vertebral abscess extended into the ventral spinal canal at C6–7 and was identified as the cause of extradural spinal cord compression. Salmonella sp. was cultured and isolated from purulent exudate at the intervertebral space. Computed tomographic myelography has not been previously reported for assessment of discospondylitis in horses and was successful at accurately characterising spinal cord compression in addition to osteolytic changes associated with discospondylitis.

Factors that delay treatment of symptomatic metastatic extradural spinal cord compression.

Treatment delays of metastatic extradural spinal cord compression (MESCC) sometimes have been reported, but reasons for its delay have remained unclear. The purpose of this study was to assess which clinical factors are associated with treatment delays in neurologically symptomatic MESCC in the hospital settings. We reviewed medical records of MESCC patients in our institute who had at least one progressive neurological symptom (weakness, sensory changes, urinary retention, or nerve root pain), were diagnosed by magnetic resonance imaging (MRI), and were treated with at least radiotherapy. The number of days prior to treatment initiation were counted and defined as follows: from the patients' first physician visit to our hospital until MRI diagnosis [T1 (days)], from MRI diagnosis to treatment [T2 (days)], and from patients' first visit to treatment [T1+2 (days)]. Nine clinical factors that could potentially delay treatment were analyzed for each period. Forty-three episodes of MESCC met the inclusion criteria. Median days in T1+2 was 3 days (range: 0-22). T1 and T1+2 were significantly higher in patients with normal walking status than in those with deterioration or inabilities to walk (T1+2, 7 days versus 3 days, median, p<0.001). The number of days was higher in all periods when it included weekends (T1+2, 7 days versus 2 days, median, p<0.001). Our findings suggest that normal walking status at the first physician visit and inclusion of weekends during the pretreatment periods were factors that resulted in treatment delays even for MESCC patients with emergency neurological symptoms.

Surgical management of vertebral synovial cysts in a rabbit (Oryctolagus cuniculus)

An approximately 8-month-old female Miniature Lop rabbit (Oryctolagus cuniculus) was evaluated because of an acute onset of progressive paraparesis. The rabbit was ambulatory paraparetic, and results of neurologic examination were consistent with a myelopathy localizing to the T3-L3 spinal cord segments. Evaluation with CT myelography revealed focal extradural spinal cord compression bilaterally at the level of the articular process joints of T12-L1. A Funkquist type A dorsal laminectomy was performed at T12-L1, and the vertebral column was stabilized with pins and polymethylmethacrylate-based cement. Multiple vertebral synovial cysts were confirmed on histologic evaluation of the surgically excised tissues. The rabbit was nonambulatory with severe paraparesis postoperatively and was ambulatory paraparetic at a recheck examination 7 weeks after surgery. Fourteen weeks after surgery, the rabbit appeared stronger; it walked and hopped slowly but still fell and dragged its hindquarters when moving faster. Thirty-seven weeks after surgery, the neurologic status was unchanged. Although thoracolumbar myelopathy in rabbits is commonly secondary to vertebral fracture, vertebral synovial cysts should be considered a differential diagnosis for rabbits with slowly progressive paraparesis. Decompressive surgery and stabilization can result in a good outcome for rabbits with this condition.

Spontaneous regression of lumbar Hansen type 1 disk extrusion detected with magnetic resonance imaging in a dog

A 3-year-old French Bulldog was evaluated because of acute signs of back pain and spastic paraparesis. Neuroanatomic localization indicated a lesion in the T3-L3 spinal cord segment. Magnetic resonance imaging revealed extradural spinal cord compression at the ventral right aspect of the intervertebral disk space L3-4. On the basis of these findings, a diagnosis of sequestrated Hansen type 1 disk extrusion without extradural hemorrhage was made. The dog was treated conservatively with cage rest, restricted exercise on a leash, and NSAIDs. Results of follow-up examination 5 weeks later indicated complete resolution of clinical signs, and results of repeated MRI indicated a 69% reduction in the volume of the herniated disk material. Findings for the dog of this report indicated spinal cord compression attributable to extruded intervertebral disk material resolved. Functional improvements in dogs with such problems may be partly attributable to spontaneous regression of intervertebral disk extrusions.

Paraparesis as initial manifestation of a Prototheca zopfii infection in a dog

A case of protothecosis causing non-ambulatory paraparesis in a dog without clinical evidence of disseminated infection is described. A five-year-old female Labrador retriever was referred with a 10-day history of progressive non-ambulatory paraparesis and lumbar pain as the only physical and neurological abnormalities. Lumbar myelography revealed severe extradural spinal cord compression extending from L4 to L7 vertebrae, and a right hemilaminectomy was performed. Surgical findings included an adherent whitish hard ill-defined mass. Cytology and biopsy results disclosed the presence of algae enclosed in a matrix of chronic inflammatory infiltrate. Culture confirmed the presence of Prototheca species. Neurological improvement occurred within a month, and the dog received antifungal treatment without evidence of clinical disseminated disease for 6 months, but died after a generalised tonic-clonic seizure. Post-mortem examination revealed multiple foci of inflammatory granulomatous infiltrate and algae-like structures in the brain, lumbar intumescence and cauda equina. Prototheca zopfii was identified using molecular biology methods.