Search PubMed⌕ Search

Biomedical subjects

T C Origitano

Publications and source records attributed to T C Origitano.

At least 19 recordsLinked to original sources
PubMed2004

Obliteration of a tentorial dural arteriovenous fistula causing spinal cord myelopathy using the cranio-orbito zygomatic approach.

BACKGROUND: Intracranial dural arteriovenous fistulas account for 10 to 15% of all intracranial arteriovenous malformations. Tentorial dural arteriovenous fistulas with spinal medullary venous drainage causing spinal cord myelopathy are very rare, but have been previously described. We describe a case using a cranio-orbito zygomatic approach with intraoperative angiography for the surgical treatment of a tentorial artery dural arteriovenous fistula causing spinal cord myelopathy. CASE PRESENTATION: A 42-year-old male presented complaining of a 1-year history of incoordination and dizziness and a 2-month history of progressive myelopathy with bowel and bladder incontinence. The patient had magnetic resonance imaging (MRI) performed along with cerebral and spinal angiography that revealed a right tentorial artery dural arteriovenous fistula with spinal medullary venous involvement down to T11. Angiographic embolization was attempted, but selective catheterization was unsuccessful. The patient underwent a cranio-orbito zygomatic approach with obliteration of the dural arteriovenous fistula. An intraoperative angiogram confirmed complete obliteration of the dural arteriovenous fistula. CONCLUSION: Intracranial dural arteriovenous fistulas are a rare cause of spinal cord myelopathy. When a patient presents with suspicion of spinal dural fistula and negative spinal angiography, an intracranial origin should be suspected and a cerebral angiogram performed. Skull base approaches along with intraoperative angiography provide an alternative modality for obliteration of the dural arteriovenous fistula nidus, thereby eliminating the venous congestion and hence the spinal cord ischemia.

Adult↗
PubMed2001

Endovascular treatment of transverse-sigmoid sinus dural arteriovenous malformations presenting as pulsatile tinnitus.

Transverse-sigmoid sinus dural arteriovenous malformations (DAVM) are uncommon vascular lesions for which complete cure may be difficult to obtain. A wide variety of treatments for these lesions include observation, arterial compression, surgical resection, and endovascular embolization. We propose that transverse-sigmoid sinus DAVM can be completely cured by occluding the ipsilateral dural sinus with detachable balloon and Guglielmi detachable coils (GDC) coils before arterial feeder embolization with histoacryl. Three patients who presented with pulsatile tinnitus and normal magnetic resonance imaging (MRI) studies underwent angiography, which demonstrated transverse-sigmoid sinus DAVM. All three patients wer treated with retrograde transvenous sinus embolization with complete occlusion of the transverse-sigmoid sinus with detachable balloons and GDC coils with preservation of the vein of Labbé. Subsequently, the various feeders from the external carotid artery were embolized. The tentorial arteries arising from the ipsilateral internal carotid arteries were not embolized in any of the cases, which were still contributing to the DAVM. Complete cure with thrombosis of the tentorial branch of the internal carotid artery (ICA) was seen on follow-up angiogram 1 day after embolization in one patient and on 4-week and 6-week follow-up angiograms in the other two patients. Complete occlusion of the transverse sinus proximal to the vein of Labbé, in spite of incomplete arterial feeder embolization, can result in complete cure of the transversesinus dural AVF if adequate time is given for the remaining feeders to occlude, once the fistula is obliterated.

Journal Article↗
PubMed2001

Carotid-cavernous fistulas: pathogenesis and routes of approach to endovascular treatment.

The etiology, classification, clinical presentation, complications, and intravascular routes to image and treat carotid-cavernous fistulas percutaneously are described. Endoarterial and transvenous approaches (through the jugular, inferior petrosal, or cavernous veins) are discussed in relation to the etiology, size, and characteristics of the fistulas, as well as in relation to the planned therapeutic approach and its possible complications. Possible outcomes, with particular attention to the internal carotid circulation, side effects, and complications also are discussed in relation to etiology and type of fistula. Four exemplary cases are presented.

Case Reports↗
PubMed2000

Frameless stereotactic localization in cranial base surgery.

Mastery of the three-dimensional anatomic relationships of the cranial base/paranasal sinuses is required to reduce the incidence of iatrogenic surgical complications, facilitate complete tumor extirpation, and enhance functional outcomes. Real-time intraoperative localization technology is one method available to assist the cranial base surgeon. We report our institutional experience with the StealthStationtrade mark treatment guidance platform. Eighty-eight consecutive patients with pathology of the cranial base/paranasal sinuses were operated on with the aid of real-time frameless stereotactic localization. Preoperative image data sets were acquired with either CT or MRI scans. Patient demographics, accuracy of the data sets, surgical approaches, pathology, complications, and further applications of this technology are presented. Procedures were performed on 47 women and 41 men ranging in age from 6 to 85 years. In these 88 procedures, 44 MRI and 44 CT scans with a mean accuracy of 1.57 and 1.23 mm, respectively, were used. Approaches to the cranial base included midface degloving (25), endoscopic (23), craniofacial (13), maxillectomy (12), rhinotomy without maxillectomy (5), transoral (5), pterional (2), transcondylar (1), and transcervical (2). Indications for surgery included severe inflammatory disease of the paranasal sinuses with epidural or subdoral abscess, or both (7), cerebrospinal fluid fistula or encephalocele, or both (11), and 40 benign and 30 malignant tumors. Complications occurred in 10 of 88 patients (11%). Real-time intraoperative localization can be applied to cranial base surgery in a variety of scenarios. The instantaneous transfer of imaging data to the surgical field is useful in localizing pathology, enhancing operative safety, and reducing morbidity, thereby improving outcomes. This technology will certainly play an integral role in minimizing complications and improving surgical outcomes as cranial base surgery moves into the next millennium.

Journal Article↗
PubMed1999

Optimal clip application and intraoperative angiography for intracranial aneurysms.

BACKGROUND: The actual incidence of residual aneurysm after clipping is unknown. The natural history of residual aneurysm can be regrowth and hemorrhage. Intraoperative angiography offers a cost-effective, safe interdiction to the problem of residual aneurysm and parent vessel stenosis. METHODS/RESULTS: Forty consecutive patients harboring 54 aneurysms underwent 42 operative procedures to clip 52 aneurysms, during which 220 intraoperative angiographic runs were performed. Ninety-three percent of the procedures were performed on patients with acute subarachnoid hemorrhage. There were 4 giant (>2.5 cm, 4/52 = 8%, all anterior circulation), 21 large (1.0-2.5 cm, 21/52 = 40%, 16/ 21 = 76% anterior circulation, 6/21 = 28% posterior circulation), and 27 small (<1.0 cm, 27/52-52%, 22/27 = 81% anterior circulation, 5/27 = 18% posterior circulation) aneurysms. Intraoperative angiography led to clip adjustment in 18/52 = 34% of aneurysms (4/18 = 22% for parent artery stenosis, 8/18 = 44% for residual aneurysm and 6/18 = 33% for both). Of the 18 adjustments made, 16 = 88% were made on giant or large aneurysms and two were small (one was a complex anterior communicating and one was a vertebral junction aneurysm). Follow-up angiography was performed on 26/42 = 62% of operative cases. Postoperative angiography confirmed intraoperative angiography in all cases. Two complications occurred during 220 angiographic runs: one embolic stroke and one incident of equipment failure. CONCLUSION: A grading scale was applied to test the relationship between anatomical site and size as they relate to the necessity for clip adjustment for complete aneurysm obliteration and/or parent artery compromise. Significance was related to site (basilar bifurcation, anterior communicating, middle cerebral bifurcation, and ophthalmic) and size (>1.0 cm), both as independent and codependent variables. An analysis of the cost-effectiveness of intraoperative angiography was demonstrated.

Adult↗
PubMed1998

PLA2 activity regulates Ca2+ storage-dependent cellular proliferation.

The objective of this study is to determine the role of arachidonic acid (AA) in cell proliferation by inhibiting AA synthetic enzyme phospholipase A2 (PLA2) and to determine its involvement in the role of the second messenger intracellular calcium (Ca2+). Methods used to determine the effects on proliferation of cell cultures of primary meningioma and astrocytoma U373-MG included treatment with micromolar concentrations of PLA2 inhibitors 4-bromophenacylbromide and quinacrine. Effects of these drugs on proliferation were further investigated by the application of concentrations that inhibit growth by 50% while antagonizing these agents with AA replacement. Free cytosolic Ca2+ was measured with the use of fluorescent dye Fura-2 during PLA2 agonist/antagonist studies. These Ca2+ measurements were performed in the absence of extracellular Ca2+ to identify the contribution of intracellular Ca2+ sources. PLA2 inhibition resulted in decreased growth of cultured astrocytoma and meningioma cells in a dose-dependent manner in the micromolar range. This inhibitory effect was antagonized by the addition of AA. PLA2 inhibition caused an elevation of basal-cytosolic-free [Ca2+] while depleting internal Ca2+ stores. These Ca2+ changes were also antagonized by the addition of AA. In conclusion, these results demonstrate that AA, a PLA2 enzyme product, is involved in regulating the growth rate of these cell types. The PLA2 pathway also regulates the maintenance of the internal Ca2+ stores. Ca2+ is known to be a growth-related intracellular second messenger. These results suggest that the growth regulatory functions of AA are mediated by Ca2+-dependent mechanisms.

Astrocytoma↗
PubMed1998

Familial cervical spondylosis. Case report.

Cervical spondylosis is a disease that is often attributed to aging and considered the result of degenerative changes in the spine. The idea that there is a genetic predisposition to develop diseases of the skeletal elements of the spine has been discussed previously, but has never been proven conclusively. The authors report three cases of severe cervical spondylosis in patients who are first-degree relatives: a mother and her two sons. All three individuals had cervical disc herniations and stenosis at C3-4, C4-5, C5-6, and C6-7, and all three required decompressive procedures. The location and degree of cervical spondylosis were as similar among these three patients as they have been in identical twins reported in other studies. Such familial inheritance of cervical spondylosis has been reported only once. The existence of familial cervical spondylosis is not an unrealistic proposal because other studies have shown that genetics determines the shape of one's spine and that similar spines tend to degenerate in similar ways. Therefore, genetic counseling for a family such as the one reported here may prove to be of great benefit to warn siblings that they are at high risk for cervical spine injury. However rare it might be, familial cervical spondylosis may be a phenomenon that any spine surgeon should suspect in a family with cervical spine abnormalities found in several members.

Adult↗
PubMed1997

Venous drainage of the inferolateral temporal lobe in relationship to transtemporal/transtentorial approaches to the cranial base.

OBJECTIVE: Intimate to the application of lateral transtemporal approaches to the cranial base are the identification, manipulation, and/or the sacrifice of the venous anatomy of the inferolateral temporal lobe and the superior petrosal sinus and the transection of the tentorium. This study demonstrates the relationship and variability of the venous drainage of the lateral and inferior surfaces of the temporal lobe. METHODS: Twenty-one specially prepared, injected cadaver specimens yielded 40 temporal lobes for examination. The venous systems in these specimens were traced from their origins on the temporal lobe (venous drainage complexes) to the transverse/petrosal sinuses, and the geometry of these venous complexes (venous configuration) was noted. The measurements of each complex's entry to the sinuses were noted. RESULTS: Four distinct venous drainage complexes were identified: 1) the lateral complex, 2) the anteroinferior complex, 3) the medial-inferior complex, and 4) the posteroinferior complex. Three basic venous configurations were found: 1) the candelabra of veins uniting to form one large draining vein, 2) multiple independent draining veins, and 3) venous lakes running in the tentorium before entering the sinuses. The lateral complex, incorporating the classic "vein of Labbé," was present in 100% of the specimens. However, in the majority of cases, it did not represent the dominant venous drainage of the lateral and inferior surfaces of the temporal lobe. CONCLUSION: An understanding of the complexity and diversity of the venous drainage complexes and their configurations is necessary to avoid venous complications during lateral cranial base surgery.

Cerebral Veins↗
PubMed1996

Lazaroids inhibit proliferation of cultured human astrocytoma cells.

Lazaroids (or 21-aminosteroids) are potent lipid peroxidation inhibitors and are more potent antioxidants than steroids which have been shown to suppress tumor proliferation. The effects of two lazaroid compounds (U-75389G and U-83836E) were tested on the proliferation of a human brain astrocytoma cell line U-373MG. Both lazaroids had dose-dependent growth-inhibitory effects on the proliferation of U-373MG. For purposes of comparison, two steroids (methylprednisolone and dexamethasone) and a highly potent antioxidant (alpha-tocopherol) were tested under similar experimental conditions and were found to have antiproliferative effects as well, although at higher dose ranges. As cell growth-inhibitors, lazaroids are more effective than alpha-tocopherol while they are advantageous over glucocorticoids for their actions are devoid of the usual glucocorticoid side-effects.

Antineoplastic Agents↗
PubMed1996

The need for neurological surgery programs to be departments.

The Decade of the Brain has brought recognition of the contributions neurological surgery has made to modern medicine, and neurological surgery training programs are a cornerstone of these achievements. While neurosurgeons are celebrating their achievements, however, a number of social, political, and administrative issues threaten to undermine the future of these programs. We discuss the ramifications of departmental status to the future of neurological surgery. These include the implications for operative experience-for example, carotid endarterectomy, spine instrumentation, acoustic tumors-the economic impact of a department versus a division, the ability to direct research, administrative input at the institutional level, and self-determination. We discuss the requirements for programmatic change and recommendations for national support.

Education, Medical↗
PubMed1996

CT angiographic-guided frameless stereotactic-assisted clipping of a distal posterior inferior cerebellar artery aneurysm: technical case report.

BACKGROUND: The development of frameless stereotaxis allows for repetitive intraoperative localization with millimeter accuracy. High-resolution computed tomographic (CT) angiography provides multiplanar, three-dimensional imaging of cerebral vascular lesions. The image data set generated during CT angiography can be used for localization in frameless stereotaxis when performed with appropriate fiducials in place. METHODS: The feasibility of melding these two technologies was tested on a patient with a small (5 mm), distal ruptured posterior inferior cerebellar artery aneurysm, which was visualized by CT angiography and localized by frameless stereotaxis. RESULTS: Visualization by CT angiography and intraoperative localization by frameless stereotaxis were successful. CONCLUSIONS: The practical application of this technology meld is demonstrated in this sample case. Applications to distal anterior cerebral artery aneurysms, abnormal flow-related aneurysms associated with arteriovenous malformations, and mycotic aneurysms are discussed.

Angiography↗
PubMed1996

Endoscopic closure of postsurgical anterior cranial fossa cerebrospinal fluid leaks.

OBJECTIVE: The primary objective of this study is to present an alternative technique to closure of anterior cranial fossa cerebrospinal fluid (CSF) leaks. This study also serves to review our experience with our technique and presents some technical "tricks" we have learned through experience. METHODS: The design of this study is a clinical chart review. The setting is an academic medical center. RESULTS: Eight patients were referred for closure of postsurgical CSF leaks. Seven of eight patients underwent closure with one attempt and closure was achieved after a second attempt in one patient. Follow-up ranged from 1.5 to 4.0 years. There were no complications. No patient developed an acute or delayed episode of meningitis. CONCLUSION: The technique of endoscopic closure of a CSF leak is a safe and effective means for closure of a postsurgical anterior cranial fossa CSF fistula when performed by an experienced operator.

Adenoma↗
PubMed1995

Vasospasm after resection of skull base tumors.

Vasospasm after resection of skull base tumors is a rare complication that often produces serious ischemic sequelae. In four of the authors' recent cases, vasospasm complicated the patient's postoperative course. A review of the literature produced a number of cases that can help determine possible causes of vasospasm after tumor resection, ways to prevent it, and methods to evaluate it when it occurs. The cause appears to be multifactorial and the surgical approach may contribute to the pathogenesis of vasospasm. Physicians must have a high degree of suspicion to detect vasospasm at an early stage of skull base surgery. Cerebral blood flow measurement and transcranial Doppler are useful monitoring tools.

Adenocarcinoma↗
PubMed1995

Reconstructing complex cranial defects with a preformed cranial prosthesis.

Large cranial defects (70 cm(2) or more) of complex geometric shapes (bifrontal or involving supraorbital ridges) that are associated with significant cutaneous contracture or soft tissue loss are challenging to reconstruct. We have treated 10 patients with complex cranial defects through a staged approach. Reconstructing the defect involved several steps. Before each surgery, we constructed a craniofacial prosthesis from polymethyl methacrylate to fit the patient's individual defect. When indicated, adjacent skin was expanded with a subcutaneous tissue expander. Finally, we carried out a cranioplasty and placed the prosthesis. Operative closure of the defect was facilitated by microplate and screw fixation with minimal prothesis contouring. Secure, vital, nontension skin closure was performed with the delayed, expanded local flap. Exposure to free polymer and exothermic reaction was avoided. Cosmetic results in these patients with high-volume, geometrically complex defects were excellent. No complications occurred, and the overall operative time was shortened.

Journal Article↗
PubMed1995

In vitro growth inhibition of growth factor-stimulated meningioma cells by calcium channel antagonists.

Studies have shown that a majority of meningiomas contain receptors for platelet-derived growth factor and epidermal growth factor and that these growth factors promote the proliferation of meningioma cells in culture. Although the mechanism of action has not been elucidated, intracellular calcium appears to be part of the signal transduction mechanism. Because alterations in intracellular calcium could interrupt this pathway and decrease cellular proliferation, we investigated the effects of calcium channel-blocking agents on the growth of meningioma cells in vitro. Primary meningioma cell cultures were established, and the cells were characterized by light and electron microscopy and by immunohistochemical studies. Then, the cultures were given growth factors and/or various calcium channel antagonists, and growth rates were measured. A dose-response decrease in cell growth was seen when verapamil, nifedipine, or diltiazem (voltage-dependent calcium channel-blocking agents) was added to serum-containing media. Also, these drugs blocked the growth stimulation of epidermal growth factor and platelet-derived growth factor in a similar fashion. Dantrolene, which inhibits the release of sequestered intracellular calcium, was also an effective blocker of the mitogenic stimulation of these growth factors.

Adult↗