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M. Yashar S. Kalani, Nikolay L. Martirosyan, Andrew S. Little, Udaya K. Kakarla and Nicholas Theodore

The authors describe a rare case of tumoral calcinosis (TC) of the thoracic spine in a 13-year-old boy with thoracic scoliosis. The patient presented with a 2-year history of back pain. He had no personal or family history of bone disease, deformity, or malignancy. Magnetic resonance imaging revealed a heterogeneously enhancing mass involving the T-7 vertebral body and the left pedicle. Computed tomography findings suggested that the mass was calcified and that this had resulted in scalloping of the vertebral body. The lesion was resected completely by using a left T-7 costotransversectomy and corpectomy. The deformity was corrected with placement of a vertebral body cage and pedicle screw fixation from T-5 to T-9. Pathological analysis of the mass demonstrated dystrophic calcification with marked hypercellularity and immunostaining consistent with TC. This represents the third reported case of vertebral TC in the pediatric population. Pediatric neurosurgeons should be familiar with lesions such as TC, which may be encountered in the elderly and in hemodialysis-dependent populations, and may not always require aggressive resection.

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M. Yashar S. Kalani, Kaan Yagmurlu, Nikolay L. Martirosyan, Daniel D. Cavalcanti and Robert F. Spetzler

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Vernard S. Fennell, Nikolay L. Martirosyan, Sheri K. Palejwala, G. Michael Lemole Jr. and Travis M. Dumont


Endovascular treatment of cerebrovascular pathology, particularly aneurysms, is becoming more prevalent. There is a wide variety in clinical background and training of physicians who treat cerebrovascular pathology through endovascular means. The impact of clinical training background on patient outcomes is not well documented.


The authors conducted a retrospective analysis of a large national database, the University HealthSystem Consortium, that was queried in the years 2009–2013. Cases of both unruptured cerebral aneurysms and subarachnoid hemorrhage treated by endovascular obliteration were studied. Outcome measures of morbidity and mortality were evaluated according to the specialty of the treating physician.


Elective embolization of an unruptured aneurysm was the procedure code and primary diagnosis, respectively, for 12,400 cases. Patients with at least 1 complication were reported in 799 cases (6.4%). Deaths were reported in 193 cases (1.6%). Complications and deaths were varied by specialty; the highest incidence of complications (11.1%) and deaths (3.0%) were reported by neurologists. The fewest complications were reported by neurosurgeons (5.4%; 1.4% deaths), with a higher incidence of complications reported in cases performed by neurologists (p < 0.0001 for both complications and deaths) and to a lesser degree interventional radiologists (p = 0.0093 for complications). Subarachnoid hemorrhage was the primary diagnosis and procedure for 8197 cases. At least 1 complication was reported in 2385 cases (29%) and deaths in 983 cases (12%). The number of complications and deaths varied among specialties. The highest incidence of complications (34%) and deaths (13.5%) in subarachnoid hemorrhage was in cases performed by neurologists. The fewest complications were in cases by neurosurgeons (27%), with a higher incidence of complications in cases performed by neurologists (34%, p < 0.0001), and a trend of increased complications with interventional radiologists (30%, p < 0.0676). The lowest incidence of mortality was in cases performed by neurosurgeons (11.5%), with a significantly higher incidence of mortality in cases performed by neurologists (13.5%, p = 0.0372). Mortality rates did not reach statistical significance with respect to interventional radiologists (12.1%, p = 0.4884).


Physicians of varied training types and backgrounds use endovascular treatment of ruptured and unruptured intracerebral aneurysms. In this study there was a statistically significant finding that neurosurgically trained physicians may demonstrate improved outcomes with respect to endovascular treatment of unruptured aneurysms in this cohort. This finding warrants further investigation.

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Alberto Maud, Gustavo J. Rodriguez, Paisith Piriyawat and Salvador Cruz-Flores

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Nikolay L. Martirosyan, Jeanne S. Feuerstein, Nicholas Theodore, Daniel D. Cavalcanti, Robert F. Spetzler and Mark C. Preul

The authors present a review of spinal cord blood supply, discussing the anatomy of the vascular system and physiological aspects of blood flow regulation in normal and injured spinal cords. Unique anatomical functional properties of vessels and blood supply determine the susceptibility of the spinal cord to damage, especially ischemia. Spinal cord injury (SCI), for example, complicating thoracoabdominal aortic aneurysm repair is associated with ischemic trauma. The rate of this devastating complication has been decreased significantly by instituting physiological methods of protection. Traumatic SCI causes complex changes in spinal cord blood flow, which are closely related to the severity of injury. Manipulating physiological parameters such as mean arterial blood pressure and intrathecal pressure may be beneficial for patients with an SCI. Studying the physiopathological processes of the spinal cord under vascular compromise remains challenging because of its central role in almost all of the body's hemodynamic and neurofunctional processes.

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M. Yashar S. Kalani, John E. Wanebo, Nikolay L. Martirosyan, Peter Nakaji, Joseph M. Zabramski and Robert F. Spetzler

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Cavernous malformations

Issam A. Awad

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Daniel D. Cavalcanti, M. Yashar S. Kalani, Nikolay L. Martirosyan, Justin Eales, Robert F. Spetzler and Mark C. Preul

Over the past half century molecular biology has led to great advances in our understanding of angio- and vasculogenesis and in the treatment of malformations resulting from these processes gone awry. Given their sporadic and familial distribution, their developmental and pathological link to capillary telangiectasias, and their observed chromosomal abnormalities, cerebral cavernous malformations (CCMs) are regarded as akin to cancerous growths. Although the exact pathological mechanisms involved in the formation of CCMs are still not well understood, the identification of 3 genetic loci has begun to shed light on key developmental pathways involved in CCM pathogenesis. Cavernous malformations can occur sporadically or in an autosomal dominant fashion. Familial forms of CCMs have been attributed to mutations at 3 different loci implicated in regulating important processes such as proliferation and differentiation of angiogenic precursors and members of the apoptotic machinery. These processes are important for the generation, maintenance, and pruning of every vessel in the body. In this review the authors highlight the latest discoveries pertaining to the molecular genetics of CCMs, highlighting potential new therapeutic targets for the treatment of these lesions.

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Nikolay L. Martirosyan, M. Yashar S. Kalani, Peter Nakaji and Robert F. Spetzler

The anterior interhemispheric approach is a workhorse for treatment of lesions in the third ventricle. In this case, we demonstrate the utility of this approach for resecting a complex third ventricular cavernous malformation. We discuss patient positioning, optimal location of the craniotomy, and surgical resection techniques for safe removal of these lesions. We also demonstrate the importance of gravity retraction using the falx to prevent injury to the dominant frontal lobe.

The video can be found here:

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M. Yashar S. Kalani, Nikolay L. Martirosyan, Peter Nakaji and Robert F. Spetzler

The supracerebellar infratentorial approach provides access to the dorsal midbrain, pineal region, and tentorial incisura. This approach can be used with the patient in a sitting, prone, park-bench, or supine position. For a patient with a supple neck and favorable anatomy, we prefer the supine position. The ipsilateral shoulder is elevated, the head turned to the contralateral side, the chin is tucked, and the neck extended toward the floor to open the craniocervical angle for added working room. Care must be taken to place the craniotomy laterally to make use of the ascending angle of the tentorium for ease of access to deep-seated lesions.

The video can be found here: