Long-term outcome following surgical and radiation treatment of vertebral angiomatosis in a cat

Eric C. Hans Department of Surgery, MedVet Medical & Cancer Center for Pets, 300 E Wilson Bridge Rd, Worthington, OH 43085.

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Robert M. Dudley Department of Surgery, MedVet Medical & Cancer Center for Pets, 300 E Wilson Bridge Rd, Worthington, OH 43085.

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Adam T. Watson Department of Radiology, MedVet Medical & Cancer Center for Pets, 300 E Wilson Bridge Rd, Worthington, OH 43085.

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Mark Chalkley Idexx Laboratories, 300 E Wilson Bridge Rd, Ste 200, Worthington, OH 43085.

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Kari D. Foss Department of Neurology, MedVet Medical & Cancer Center for Pets, 300 E Wilson Bridge Rd, Worthington, OH 43085.

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Ann Bancroft Department of Rehabilitation, MedVet Medical & Cancer Center for Pets, 300 E Wilson Bridge Rd, Worthington, OH 43085.

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Deborah M. Prescott Department of Radiation Oncology, MedVet Medical & Cancer Center for Pets, 300 E Wilson Bridge Rd, Worthington, OH 43085.

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Abstract

CASE DESCRIPTION A 2-year-old 5.2-kg (11.4-lb) neutered male domestic shorthair cat was referred because of a 6-week history of progressive paraparesis.

CLINICAL FINDINGS Neurologic examination revealed moderate ambulatory paraparesis with marked spinal hyperesthesia at the thoracolumbar junction. The lesion was localized to the T3-L3 spinal cord segment. Clinicopathologic testing, thoracic radiography, and abdominal ultrasonography revealed no abnormalities to explain the observed clinical signs. Advanced spinal imaging with MRI revealed an extradural right-lateralized mass originating from the L2 vertebral pedicle and causing severe spinal cord compression.

TREATMENT AND OUTCOME Surgical decompression was achieved by performance of a right-sided hemilaminectomy at L2. Histologic examination of biopsy samples obtained from the mass revealed an ill-defined zone of mature vascular proliferation extending through the preexisting vertebral bone, consistent with vertebral angiomatosis. After surgical recovery, adjuvant radiation therapy was initiated with a total dose of 48 Gy administered in 16 fractions of 3 Gy each over a 3-week period. Neurologic function rapidly improved to full ambulation with only minimal monoparesis of the right pelvic limb. Results of neurologic and MRI examination performed 26 months after surgery indicated no change in neurologic status or evidence of recurrence.

CLINICAL RELEVANCE To the authors' knowledge, this report was the first to describe the long-term outcome for vertebral angiomatosis in a cat. Surgical decompression and radiation therapy provided an excellent outcome in this case. Vertebral angiomatosis should be considered as a differential diagnosis for any young cat with thoracolumbar myelopathy secondary to a mass associated with the vertebral pedicle.

Abstract

CASE DESCRIPTION A 2-year-old 5.2-kg (11.4-lb) neutered male domestic shorthair cat was referred because of a 6-week history of progressive paraparesis.

CLINICAL FINDINGS Neurologic examination revealed moderate ambulatory paraparesis with marked spinal hyperesthesia at the thoracolumbar junction. The lesion was localized to the T3-L3 spinal cord segment. Clinicopathologic testing, thoracic radiography, and abdominal ultrasonography revealed no abnormalities to explain the observed clinical signs. Advanced spinal imaging with MRI revealed an extradural right-lateralized mass originating from the L2 vertebral pedicle and causing severe spinal cord compression.

TREATMENT AND OUTCOME Surgical decompression was achieved by performance of a right-sided hemilaminectomy at L2. Histologic examination of biopsy samples obtained from the mass revealed an ill-defined zone of mature vascular proliferation extending through the preexisting vertebral bone, consistent with vertebral angiomatosis. After surgical recovery, adjuvant radiation therapy was initiated with a total dose of 48 Gy administered in 16 fractions of 3 Gy each over a 3-week period. Neurologic function rapidly improved to full ambulation with only minimal monoparesis of the right pelvic limb. Results of neurologic and MRI examination performed 26 months after surgery indicated no change in neurologic status or evidence of recurrence.

CLINICAL RELEVANCE To the authors' knowledge, this report was the first to describe the long-term outcome for vertebral angiomatosis in a cat. Surgical decompression and radiation therapy provided an excellent outcome in this case. Vertebral angiomatosis should be considered as a differential diagnosis for any young cat with thoracolumbar myelopathy secondary to a mass associated with the vertebral pedicle.

A 2-year-old 5.2-kg (11.4-lb) neutered male domestic shorthair cat was referred because of a 6-week history of progressive pelvic limb ataxia and paraparesis. The owner reported that the cat's initial clinical signs were those of spinal discomfort, which progressed to marked paraparesis and ataxia when walking. Prior to referral, the cat had received a 2-week tapering dosage of orally administered dexamethasone, which temporarily alleviated the clinical signs; however, after this treatment was discontinued, the previous clinical signs recurred and the paraparesis continued to progress.

On initial neurologic examination, the cat was judged as having appropriate mentation and was ambulatory, with moderate paraparesis and a plantigrade posture in each pelvic limb. Conscious proprioceptive placing was lacking in both pelvic limbs. Patellar reflexes were considered hyperreflexive, consistent with an upper motor neuron lesion. Moderate hyperesthesia was elicited on focal palpation of the thoracolumbar junction. Results of cranial nerve examination and thoracic limb examination were unremarkable. Considered together, findings were consistent with T3-L3 myelopathy, and differential diagnoses included neoplasia (primarily lymphoma), feline infectious peritonitis, immune-mediated inflammatory disease, or intervertebral disk herniation.

A CBC, serum biochemical analysis, thoracic radiography, and abdominal ultrasonography were recommended as initial diagnostic tests, followed by advanced spinal imaging if no cause for the paresis could be identified. Clinicopathologic findings included a mild normocytic, normochromic, nonregenerative anemia (RBC count, 7.08 × 106/μL; reference range, 7.12 × 106/μL to 11.46 × 106/μL); mild hypocholesterolemia (serum cholesterol concentration, 77 mg/dL; reference range, 91 to 305 mg/dL); and mild hypophosphatemia (serum phosphorus concentration, 2.7 mg/dL; reference range, 2.9 to 6.3 mg/dL). Test results for FeLV and FIV infection were negative. Findings on thoracic radiography and abdominal ultrasonography were unremarkable.

The cat was anesthetized for MRI examination of the thoracolumbar portion of the spinal cord with a 1.5-T scanner.a The MRI protocol included multiplanar T2-weighted FRFSE, short tau inversion recovery, and pre- and postcontrast T1-weighted FSE sequences. A fusiform right-lateralized extradural mass measuring approximately 2.5 cm in length and 0.6 cm in width was identified in the neural canal at L2 (Figure 1). The mass appeared to be causing compression and leftward spinal cord displacement and occupied approximately 80% of the neural canal. The mass was well circumscribed and largely hypointense to the spinal cord on T2-weighted FRFSE and T1-weighted FSE sequences, with small areas of hyperintensity at its caudal aspect. It was contiguous with L2, extending into the vertebral pedicle and left side of the vertebral body. Moderate heterogeneous contrast enhancement of the soft tissue and vertebra portions of the mass was evident.

Figure 1—
Figure 1—

Representative MRI images of the thoracolumbar spinal region in a 2-year-old neutered male domestic shorthair cat evaluated because of progressive paraparesis. Images include a precontrast sagittal T2-weighted FRFSE view (A), precontrast axial T1-weighted FSE view (B), postcontrast axial T1-weighted FSE view (C), and postcontrast dorsal T1-weighted FSE view (D). A T1- and T2-weighted hypointense right-lateralized extradural mass (arrows) was identified originating from the L2 vertebral body and extending into the right pedicle. The mass occupied most of the neural canal, causing severe compression and left lateral displacement of the spinal cord. Moderate heterogeneous contrast enhancement was observed.

Citation: Journal of the American Veterinary Medical Association 253, 12; 10.2460/javma.253.12.1604

Given the MRI findings, surgery was recommended to alleviate the focal spinal cord compression and obtain biopsy samples for establishment of a histologic diagnosis. Differential diagnoses for the mass at that time included a tumor of primary bone origin (ie, osteosarcoma), although round cell neoplasia (ie, lymphosarcoma) was still given high consideration because of its common diagnosis in cats. Alternative treatment options, including radiation therapy alone or palliative care with continued medical treatment, were also discussed with the owner. The owner elected to proceed with surgical decompression.

Surgical decompression was performed via a right-sided hemilaminectomy from L1 through L3. The pedicle of L2 appeared abnormally thickened, and on entry to the neural canal, a large amount of proliferative tissue was visible ventrally, displacing the spinal cord. Grossly abnormal tissue was debulked until the spinal cord resumed a normal position within the neural canal. Several biopsy samples of the mass were obtained and submitted in formalin for histologic examination. Routine surgical closure was performed, and the cat recovered unremarkably from anesthesia.

Postoperative analgesia was provided as a continuous rate infusion of fentanyl (3 μg/kg/h [1.4 μg/lb/h], IV) overnight. The following morning, fentanyl administration was discontinued and oral transmucosal buprenorphine hydrochloride administration (0.02 mg/kg [0.01 mg/lb], q 8 h for 7 days) was initiated along with oral prednisolone administration (0.5 mg/kg [0.23 mg/lb], PO, q 12 h). The dosage of prednisolone was tapered over several weeks and then discontinued. Neurologic examination the morning after surgery revealed that the cat was nonambulatory, with good motor function in the left pelvic limb and minimal motor function in the right pelvic limb.

Histologic examination of the biopsy samples revealed extensive proliferations of redundant small-caliber blood-filled vessels of variable subtypes, including high numbers of capillaries and lesser numbers of small arterioles and venules, coursing through and widely separating the preexisting bony trabeculae. These vessels were lined by small, uniform endothelial cells and peripherally supported by pericyte-like cells or fibroblasts in some fields (Figure 2). Mild anisocytosis and anisokaryosis were present with no mitotic figures identified in 10 hpf (2.37 mm2). This benign vascular proliferation was diagnosed as vertebral angiomatosis of L2. These abnormal vascular proliferations extended to the margins of all biopsy samples.

Figure 2—
Figure 2—

Representative photomicrograph of a biopsy sample obtained from the extradural mass in the cat of Figure 1 at the time of surgical decompression. Numerous moderately dense and often tortuous, small-caliber, capillary-rich blood vessels were visible, supported by loose fibrous connective tissue. Constituent blood vessels widely separated the bony trabeculae of the preexisting vertebral body (not shown). H&E stain; bar = 50 μm.

Citation: Journal of the American Veterinary Medical Association 253, 12; 10.2460/javma.253.12.1604

Although vertebral angiomatosis is a benign vasculoproliferative disorder,1–3 clinical recurrence remained a concern because of the marginal nature of the surgical decompression. Adjuvant radiation therapy for additional local disease control was discussed with the owner, and both the beneficial and potential adverse effects were thoroughly explained. After consultation with a board-certified veterinary radiation oncologist, the owner elected to proceed with radiation therapy.

Radiation treatment was initiated 3 weeks after surgery. A radiation dose of 48 Gy was administered in 16 fractions of 3 Gy each over a 3-week period by use of 6-MV photons from a linear accelerator.b The cat remained hospitalized for much of the radiation treatment period, and no complications were noted during that period.

Clinically, strength improved in both pelvic limbs during the perioperative period. Rehabilitative therapy was recommended to assist with neurologic recovery. During the 3-week period of radiation treatment, the cat concurrently received rehabilitative treatment consisting of pelvic limb therapeutic massage and passive range-of-motion exercises, weight-shifting activities, assisted walking on a treadmill, and stepping over cavalettis, all under the guidance of a certified canine rehabilitation practitioner. When radiation therapy concluded, the cat was ambulatory with moderate monoparesis of the right pelvic limb. The owner continued therapeutic exercises at home.

Follow-up examination was performed 1 month after radiation therapy had ended. Physical examination revealed that the cat was in good health with no appreciable adverse effects of radiation therapy. Neurologic examination results at that time characterized the cat as fully ambulatory with only mild monoparesis of the right pelvic limb. No signs of spinal pain were noted, and the cat required no medications at that time. Additional follow-up examinations were performed every 3 months up to 1 year after surgery. At the 12-month examination, the owner reported no signs of paresis in the cat, which was described as highly active at home (typical ambulatory and jumping ability). Only a slight residual right pelvic limb monoparesis was found on neurologic examination.

Long-term follow-up information was available through a neurologic and MRI examination performed 26 months after surgery. The cat had no evidence of clinical recurrence at that time, and the owner reported no concerns at home. The cat's quality of life was described as excellent. Neurologic examination revealed only a mild delay in postural reactions of the right pelvic limb and the same slight monoparesis as noted at the 12-month examination. Results of MRI confirmed no recurrence of the angiomatosis at L2 (Figure 3). The MRI protocol was similar to the one used at the time of the initial diagnosis, with the addition of a postcontrast T1-weighted fat suppression sequence. Other MRI findings at this time were mild leftward displacement of the spinal cord from L1 through L3 secondary to epidural fat accumulation. Minimal spinal cord compression was noted. The right-sided hemilaminectomy site was unremarkable in appearance. Adjacent to this site, non–contrast-enhanced osteoproliferative bone was identified, consistent with a benign reaction. No contrast enhancement was identified in the region of the previous angiomatosis lesion. A heterogeneous intramedullary T2-weighted hyperintensity was identified within the spinal cord, spanning T10 through L3, and was most severe at the site of the previous angiomatosis lesion. This finding was attributed to the previous radiation therapy.

Figure 3—
Figure 3—

Representative MRI images of the thoracolumbar spinal region in the cat of Figure 1, obtained 26 months after surgical decompression and radiation therapy for treatment of vertebral angiomatosis of L2. Images include postcontrast axial (A) and dorsal (B) T1-weighted fat suppression views and axial (C) and sagittal (D) T2-weighted FRFSE views. Resolution of spinal cord compression was evident in all planes, with no evidence that the angiomatosis had recurred. A mild leftward shift of the spinal cord was identified that was believed to be attributable to accumulation of fat within the neural canal. A benign osteoproliferation was present along the right side of the vertebral column adjacent to the previous laminectomy site (arrows). The complete lack of contrast enhancement in this region excluded the possibility of angiomatosis recurrence. An intramedullary T2-weighted hyperintensity, most appreciated in the sagittal plane (asterisks), was found extending from T10 to L3.

Citation: Journal of the American Veterinary Medical Association 253, 12; 10.2460/javma.253.12.1604

Discussion

Vertebral angiomatosis is a rarely reported cause of thoracolumbar myelopathy in cats.1–3 Prior to this report, this condition had been described in only 5 cats. The diagnosis was made at postmortem examination for 2 of those cats and following surgical biopsy for the other 3 cats.1–3 Of the 3 surgically treated cats, 1 died immediately after surgery and the other 2 had neurologic improvement; however, the clinical follow-up period for those cats was limited to 4 months. No adjuvant treatment was performed for any of the 5 cats.

For the cat of the present report, the combination of surgical decompression and adjuvant radiation therapy resulted in an excellent functional outcome with no evidence of recurrence 26 months after the initial diagnosis of vertebral angiomatosis. The diagnosis of vertebral angiomatosis was determined by histologic examination of biopsy samples obtained during surgical decompression of the spinal cord. Extensive unencapsulated proliferations of mature small-caliber blood vessels were identified, consistent with previously reported histologic features of vertebral angiomatosis in cats.2 These vascular proliferations, although aggressive and expansile, are not recognized as a true neoplasm because multiple cell types (smooth muscle myocytes, fibroblasts, and pericytes) are often present.2 Consequently, this type of lesion has also been characterized in some reports1,2 as a vascular malformation. Similar lesions have been histologically described in the human medical literature4–8 with terms such as skeletal angiomatosis, vertebral hemangioma, lymphangiomatosis, and hamartoma. In people, such lesions are believed to develop secondary to a vascular malformation.5,8,9

We found it difficult to advise the cat's owner on expected prognosis, primarily because of the lack of available long-term outcome data for vertebral angiomatosis in cats. Short-term clinical improvement has reportedly been achieved with surgical decompression alone.1,2 The long-term risk of clinical recurrence following surgical decompression alone is unknown; however, the location of vertebral angiomatosis precludes complete surgical resection and intuitively puts the patient at risk of clinical recurrence. Our primary concern was that the biological behavior of vertebral angiomatosis would mimic that of a low-grade vascular neoplasm with continued proliferation, resulting in recurrent spinal cord compression and neurologic deficits.

In people, vertebral hemangiomas have been characterized as benign vascular malformations that aggressively expand the vertebral body, resulting in spinal cord compression and corresponding neurologic deficits.9–12 Clinical recurrence is possible when vertebral hemangiomas are treated by surgical decompression alone.9,12 In 1 study,9 surgical decompression alone was associated with clinical recurrence in 3 of 6 affected patients, whereas surgery combined with radiation therapy resulted in no clinical recurrence. Clinical recurrence in that study9 was noted as early as 12 months after surgery.

Adjuvant radiation therapy is the standard of care for people with a vertebral hemangioma lesion following incomplete or subtotal surgical decompression.9–11 Radiation therapy is readily available to veterinary patients and is often used for cats and dogs with spinal neoplasia with or without concurrent surgical decompression.13–15 Extrapolation of human findings to veterinary patients should be done with caution; however, given the demonstrated sensitivity of vertebral vascular malformations to radiation therapy in people, the use of adjuvant radiation therapy was proposed for the cat of the present report to improve long-term disease control.

Radiation therapy is not a benign treatment method, so it is important that the potential for immediate and delayed injury to the spinal cord be discussed with owners, the most serious injury being irreversible radiation myelopathy. Clinical signs of radiation myelopathy can range from minor motor and sensory deficits to complete paralysis, with a typical onset between 9 and 18 months after treatment.16–20 Without knowledge of the true benefit of radiation therapy for vertebral angiomatosis, we chose a radiation dose to minimize the risk of developing delayed spinal cord injury. Radiation tolerance for healthy spinal cord tissue has been reported for dogs, with approximately a 1% risk of developing permanent radiation myelopathy when receiving a total of 44 Gy in 4-Gy fractions.18–20 In people, total radiation doses of 45 to 50 Gy in 2-Gy daily fractions are associated with only a 0.2% risk of permanent radiation myelopathy.16 The cat of the present report received a total of 48 Gy in 3-Gy fractions, and although the normal tissue tolerance for the spinal cord has yet to be reported for cats, we estimated from the reported tolerances of these other species that the risk of permanent myelopathy would be extremely low. At > 2 years after radiation therapy, the cat of the present report had no worsening in neurologic function to suggest clinical recurrence or delayed radiation-induced myelopathy. We recommended that the cat receive routine neurologic examinations for the remainder of its life to monitor for recurrence of vertebral angiomatosis or myelopathies related to radiation therapy.

Additional investigation is required to understand the extent to which radiation therapy may prevent clinical recurrence of vertebral angiomatosis, compared with surgical decompression alone. As previously stated, clinical recurrence from similar vasculoproliferative lesions is possible in people as early as 12 months after surgery alone. Given the marginal nature of surgical resection for diseases involving the vertebral column, combined with the relatively low risk of delayed radiation-induced myelopathy, radiation therapy should be discussed as an adjuvant treatment option with owners of cats with vertebral angiomatosis until more information is available. Studies of long-term clinical outcome are needed to best determine the ideal treatment strategy for vertebral angiomatosis in cats.

The etiopathogenesis of vertebral angiomatosis in cats is not fully understood. A predilection appears to exist for angiomatosis formation in young versus older cats, likely indicating a developmental component.1–3 Similar to previously reported cases, the cat of the present report was only 2 years old at the time of diagnosis, thereby highlighting the importance of long-term disease control. Interestingly, the angiomatosis lesion in the cat of the present report involved L2; however, the previously reported cases involved the caudal thoracic vertebrae.1–3 As such, vertebral angiomatosis should not be excluded from consideration when investigating a myelopathy in the lumbar spinal region of a cat.

To the authors' knowledge, the present report represents the first detailed description of the initial and follow-up MRI findings for vertebral angiomatosis in a cat. Imaging modalities reported previously in the diagnosis of vertebral angiomatosis have included radiography, myelography, and CT.1–3 However, in right lateral and ventrodorsal thoracic radiographs of the cat of the present report, L2 had an unremarkable appearance. Vertebral angiomatosis lesions may not be apparent on survey radiographs, and CT or MRI should be recommended to obtain an imaging diagnosis for cats with thoracolumbar myelopathy. We used MRI to make the initial diagnosis and repeated the scan 26 months later to evaluate the cat for recurrence. The MRI findings at the time of initial diagnosis were those of a right-lateralized, extradural, fusiform mass with hypointensity on both T1- and T2-weighted sequences, with moderate heterogeneous contrast enhancement. The connection of the mass with the vertebral pedicle suggested a primary bone tumor origin, although no MRI features could distinguish this mass from other benign or malignant tumor types.

Repeated MRI after treatment confirmed resolution of spinal cord compression and the lack of recurrence given that no contrast enhancement was observed in the L2 region. All osseous changes in this region were considered benign and consistent with the previous surgery. An intramedullary T2-weighted hyperintensity was identified and attributed to the previous radiation therapy. Reported histopathologic spinal cord changes following radiation therapy include various degrees of reactive gliosis, demyelination, and necrosis.18,19,21 The clinical importance of the observed intramedullary hyperintensity was unknown; however, given the static neurologic examination results between 12 and 26 months after surgery and radiation therapy, this finding was unlikely to have affected future functional outcome for the cat.

Use of MRI is important when investigating thoracolumbar myelopathy in cats because differential diagnoses and their associated prognoses can differ considerably.22–24 In a retrospective study,24 the most prevalent causes of myelopathy in cats ≤ 2 years of age were feline infectious peritonitis, storage disease (of unspecified nature), or trauma. These age distinctions are clinically relevant when considering MRI findings such as those at initial evaluation of the cat of the present report. Because vertebral neoplasms are less common in cats ≤ 2 years of age than in older cats,23,24 vertebral angiomatosis should be considered whenever MRI reveals a mass in a young cat with imaging characteristics similar to those described in the present report.

Acknowledgments

Funding for follow-up MRI examination was provided by the MedVet Charitable Foundation.

The authors declare that there were no conflicts of interest with respect to the research, authorship, or publication of this report.

The authors thank Josh Warnemunde for assistance with image preparation.

ABBREVIATIONS

FRFSE

Fast recovery fast spin echo

FSE

Fast spin echo

Footnotes

a.

1.5-T GE Signa Echospeed Plus, GE Healthcare, Milwaukee, Wis.

b.

Varian Clinac 2100C, Varian Medical Systems Inc, Palo Alto, Calif.

References

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  • 2. Wells MY, Weisbrode SE. Vascular malformations in the thoracic vertebrae of three cats. Vet Pathol 1987;24:360361.

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  • 4. Malik R, Malik R, Tandon S, et al. Skeletal angiomatosis—rare cause of bone destruction: a case report with review of literature. Indian J Pathol Microbiol 2008;51:515518.

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  • 5. Spjut HJ, Lindbom A. Skeletal angiomatosis. Acta Pathol Microbiol Scand 1962;55:4958.

  • 6. Steiner GM, Farman J, Lawson JP. Lymphangiomatosis of bone. Radiology 1969;93:10931098.

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  • 24. Marioni-Henry K, Vite CH, Newton AL, et al. Prevalence of diseases of the spinal cord of cats. J Vet Intern Med 2004;18:851858.

  • Figure 1—

    Representative MRI images of the thoracolumbar spinal region in a 2-year-old neutered male domestic shorthair cat evaluated because of progressive paraparesis. Images include a precontrast sagittal T2-weighted FRFSE view (A), precontrast axial T1-weighted FSE view (B), postcontrast axial T1-weighted FSE view (C), and postcontrast dorsal T1-weighted FSE view (D). A T1- and T2-weighted hypointense right-lateralized extradural mass (arrows) was identified originating from the L2 vertebral body and extending into the right pedicle. The mass occupied most of the neural canal, causing severe compression and left lateral displacement of the spinal cord. Moderate heterogeneous contrast enhancement was observed.

  • Figure 2—

    Representative photomicrograph of a biopsy sample obtained from the extradural mass in the cat of Figure 1 at the time of surgical decompression. Numerous moderately dense and often tortuous, small-caliber, capillary-rich blood vessels were visible, supported by loose fibrous connective tissue. Constituent blood vessels widely separated the bony trabeculae of the preexisting vertebral body (not shown). H&E stain; bar = 50 μm.

  • Figure 3—

    Representative MRI images of the thoracolumbar spinal region in the cat of Figure 1, obtained 26 months after surgical decompression and radiation therapy for treatment of vertebral angiomatosis of L2. Images include postcontrast axial (A) and dorsal (B) T1-weighted fat suppression views and axial (C) and sagittal (D) T2-weighted FRFSE views. Resolution of spinal cord compression was evident in all planes, with no evidence that the angiomatosis had recurred. A mild leftward shift of the spinal cord was identified that was believed to be attributable to accumulation of fat within the neural canal. A benign osteoproliferation was present along the right side of the vertebral column adjacent to the previous laminectomy site (arrows). The complete lack of contrast enhancement in this region excluded the possibility of angiomatosis recurrence. An intramedullary T2-weighted hyperintensity, most appreciated in the sagittal plane (asterisks), was found extending from T10 to L3.

  • 1. Kloc PA, Scrivani PV, Barr SC, et al. Vertebral angiomatosis in a cat. Vet Radiol Ultrasound 2001;42:4245.

  • 2. Wells MY, Weisbrode SE. Vascular malformations in the thoracic vertebrae of three cats. Vet Pathol 1987;24:360361.

  • 3. Schur D, Rademacher N, Vasanjee S, et al. Spinal cord compression in a cat due to vertebral angiomatosis. J Feline Med Surg 2010;12:179182.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 4. Malik R, Malik R, Tandon S, et al. Skeletal angiomatosis—rare cause of bone destruction: a case report with review of literature. Indian J Pathol Microbiol 2008;51:515518.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 5. Spjut HJ, Lindbom A. Skeletal angiomatosis. Acta Pathol Microbiol Scand 1962;55:4958.

  • 6. Steiner GM, Farman J, Lawson JP. Lymphangiomatosis of bone. Radiology 1969;93:10931098.

  • 7. Wallis LA, Asch T, Maisel BW. Diffuse skeletal hemangiomatosis. Report of two cases and review of literature. Am J Med 1964;37:545563.

  • 8. Young JWR, Galbraith M, Cunningham J, et al. Progressive vertebral collapse in diffuse angiomatosis. Metab Bone Dis Relat Res 1983;5:5360.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 9. Jiang L, Liu XG, Yuan HS, et al. Diagnosis and treatment of vertebral hemangiomas with neurologic deficit: a report of 29 cases and literature review. Spine J 2014;14:944954.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 10. Tarantino R, Donnarumma P, Nigro L, et al. Surgery in extensive vertebral hemangioma: case report, literature review, and a new algorithm proposal. Neurosurg Rev 2015;38:585592.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 11. Vasudeva VS, Chi JH, Groff MW. Surgical treatment of aggressive vertebral hemangiomas. Neurosurg Focus 2016;41:E7.

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