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Jacques J Morcos

Publications and source records attributed to Jacques J Morcos.

11 recordsLinked to original sources
PubMed2026

The investigation of human cerebrospinal fluid exosome in spinal cord injury.

Spinal cord injury (SCI) leads to severe neurological and functional impairments, yet reliable biomarkers for assessing injury severity and predicting recovery remain limited. Cerebrospinal fluid (CSF) is in direct contact with the central nervous system and provides a valuable source for detecting molecular changes after SCI. Although exosomal microRNAs (miRNAs) and proteins are increasingly recognized as mediators of intercellular communication, the role of human CSF exosomes in SCI has not been systematically investigated. To identify exosome-based biomarkers and potential therapeutic targets, we analyzed CSF and serum exosomes from patients with acute SCI using RNA sequencing and proteomic profiling. Weighted gene co-expression network analysis identified 6 gene modules significantly associated with injury severity and neurological recovery at 3 months. Proteomic analysis revealed a 5-protein panel that distinguished complete from incomplete SCI and a 4-protein panel that predicted neurological improvement. Additionally, 15 CSF-specific and 9 serum-specific exosomal miRNAs were identified independent of injury severity. Among 10 tested miRNAs associated with neurological recovery, 7 regulated astrocyte proliferation, and 6 promoted neurite extension and synapse formation. Overall, this study provides a comprehensive characterization of CSF exosomal miRNAs and proteins in human SCI and identifies molecular signatures associated with injury severity and recovery.

Humans↗
PubMed2006

An atypical presentation of adenoid cystic carcinoma of the lacrimal gland.

PURPOSE: To report a case of lacrimal gland adenoid cystic carcinoma (ACC) with an atypical initial presentation and to postulate an anatomical explanation for this unusual biologic behavior. DESIGN: Interventional case report. METHODS: An orbital magnetic resonance imaging study of a 58-year-old man who complained of progressive diplopia and orbital discomfort disclosed a soft tissue mass in the left cavernous sinus and orbital apex. The left lacrimal gland and the contiguous bone appeared normal. RESULTS: Biopsy of the intracranial mass revealed ACC of unknown origin which was judged to be unresectable. He underwent two cycles of intraarterial cytoreductive chemotherapy followed by a left medial maxillectomy with sphenoethmoidectomy, orbital exenteration, and chemoradiation. ACC tumor cells were identified in nerve fiber bundles surrounding and within the lacrimal gland. CONCLUSIONS: In patients presenting with an infiltrative mass in the cavernous sinus or orbital apex, metastatic disease from an occult lacrimal gland primary should be considered, even with a normal-appearing lacrimal gland.

Carcinoma, Adenoid Cystic↗
PubMed2006

Aneurysm of the anterior inferior cerebellar artery-posterior inferior cerebellar artery variant: case report with anatomical description in the cadaver.

OBJECTIVE AND IMPORTANCE: The authors report a very rare case of an aneurysm at the distal segment of the anterior inferior cerebellar artery-posterior inferior cerebellar artery (AICA-PICA) variant along with a description of the surgical anatomy of this variation in a cadaveric specimen. CLINICAL PRESENTATION: A 44-year-old woman experienced the sudden onset of severe headache and vomiting. Computed tomographic scanning revealed subarachnoid and intraventricular hemorrhage. Cerebral angiography demonstrated a saccular aneurysm arising from the tonsillomedullary segment of the right PICA and a second aneurysm arising from the cortical segment of the common trunk of an AICA-PICA variation. INTERVENTION: Via bilateral suboccipital craniotomy, both aneurysms were clipped. CONCLUSION: Only two cases of aneurysms arising from an AICA-PICA variation have been reported in the literature and no detailed description of the surgical anatomy of this variation has been carried out in previous publications. To our knowledge, the present report is the first description of a clinical case along with a detailed surgical anatomic study in a cadaver.

Adult↗
PubMed2005

Transpetrosal approaches to the posterior fossa.

Resection of the petrous temporal bone to various degrees provides different levels of access to lesions of the posterior fossa. Although their nomenclature can be confusing, the numerous variants of the transpetrosal approaches can be classified broadly into anterior and posterior groups. The posterior transpetrosal approaches include the retrolabyrinthine, translabyrinthine, and transcochlear, whereas the ones in the anterior group are extensions of the basic middle fossa approach. Both the anterior and posterior approaches have the potential of exposing the cerebellopontine angle and the petroclival region. The posterior approaches are based on the standard mastoidectomy and involve resection of the petrous bone to various degrees. This results in progressively increased exposure anteriorly, but comes at the expense of hearing in the translabyrinthine approach and of hearing and facial strength in the transcochlear approach. In contrast, the middle fossa approaches spare the lateral petrous bone and involve resection of the medial petrous bone to various degrees. All of the middle fossa approaches are designed to preserve hearing. Extensions of the middle fossa approaches involve resection of bone within the Kawase rhomboid and division of the tentorium to provide exposure of the posterior fossa.

Adult↗
PubMed2005

Arterial vascularization of primary motor cortex (precentral gyrus).

BACKGROUND: The precentral gyrus (PG) is the primary motor area and is one of the most eloquent brain regions of neurosurgical interest. Although the arterial supply to the PG is generally known, contributions from different arterial branches such as the anterior cerebral artery (ACA), posterior cerebral artery (PCA), and middle cerebral artery (MCA) have not been comprehensively studied. The aim of the present study was to provide detailed information about the arteries of the PG. METHODS: Twenty adult human brains (40 hemispheres) were obtained, and ACA, MCA, and PCA were separately cannulated and injected with latex. The PG was identified. RESULTS: The ACA supplied the medial one third and the MCA supplied the lateral two thirds of the PG. The PCA did not reach the PG in any of the hemispheres. In 16 hemispheres (40%), the callosomarginal artery and, in 13 hemispheres (32.5%), the pericallosal artery were dominant for the medial one third of the PG. In 11 hemispheres (27.5%), equal dominance was observed. MCA branches at the lateral tip of the PG were classified into precentral, central, and postcentral groups. In 29 hemispheres (72.5%), the central group, and in 4 hemispheres (10%), the precentral group were dominant for the lateral two thirds of the PG. In 7 hemispheres (17.5%), the precentral and central groups were equally dominant. No dominance was identified for the postcentral group. CONCLUSION: In each hemisphere, the PG was supplied by different vascularization patterns of ACA and MCA. The present study is the first to describe and discuss these details. Therefore, awareness of this pattern will provide a great contribution to surgical interventions.

Adult↗
PubMed2005

Cerebral revascularization in skull base tumors.

Skull base tumors involving the carotid artery pose a difficult surgical challenge. The potential for bypass grafting for cerebral revascularization carries inherent risks but may aid in tumor resection and control in those who warrant carotid sacrifice but have inappropriate natural cerebrovascular reserve. We include a review of the literature discussing the indications for carotid resection as part of skull base tumor surgery, indications for cerebral revascularization, balloon test occlusion, graft types and operative technique, complications, and results.

Journal Article↗
PubMed2005

Split cord malformation with associated type IV spinal cord perimedullary arteriovenous fistula. Case report.

The authors describe the case of a 62-year-old woman with a Type II split cord malformation (SCM). At the initial time of workup, the authors observed an associated Klippel-Feil deformity at the level of the SCM and a low-lying conus medullaris; however, they discovered an associated Type IV perimedullary spinal cord arteriovenous fistula (AVF) only after the patient continued to deteriorate following a spinal cord untethering procedure. Although prominent blood vessels have been reported within the median cleft of SCMs, an angiographically and surgically proven perimedullary AVF has not previously been described. The potential coexistence of SCM and perimedullary AVF has significant clinical implications and its recognition is critically important prior to surgical treatment.

Arteriovenous Fistula↗
PubMed2003

An alternative extradural exposure to the anterior clinoid process: the superior orbital fissure as a surgical corridor.

OBJECTIVE: Dolenc has pioneered the extradural approach to the anterior clinoid process (ACP) in approaching the cavernous sinus, clinoidal space, and orbital apex. A key step is the division of the frontotemporal dural fold (FTDF). Less experienced surgeons may not be as versatile in their three-dimensional understanding of the superior orbital fissure and thus may risk injury to its contents. Through our cadaveric and subsequent clinical experience, we have devised a modification of the approach that permits safer handling of the contents of the superior orbital fissure. METHODS: In five consecutive injected cadaveric heads (10 sides), we performed on one side a traditional extradural exposure of the ACP. On the other side, we performed our alternative dissection. Instead of exposing the ACP from medial to lateral and dividing the frontotemporal dural fold along the assumed path of safety, we followed the edge of the lesser wing from lateral to medial, uncovered the superior orbital fissure, and peeled the outer layer of the cavernous sinus medial to the foramen rotundum along the greater wing, thus uncovering the inferolateral surface of the ACP. This allowed dural division under full visualization. RESULTS: The alternative method proved easier and more reliable in every case. We applied this technical modification in seven patients with no complications. Specifically, there was no injury to the oculomotor, lacrimal, frontal, or trigeminal nerves or branches. We present detailed anatomic expositions of the injected specimens. CONCLUSION: This technical modification of the extradural approach of Dolenc is a simple, safe, and valuable adjunct to the exposure of the ACP. We recommend its use particularly by relatively inexperienced surgeons.

Brain Diseases↗
PubMed2003

Penetration of the optic nerve by an internal carotid artery-ophthalmic artery aneurysm: case report and literature review.

OBJECTIVE AND IMPORTANCE: Although it is well known that large or giant internal carotid artery-ophthalmic artery aneurysms can cause visual deficits, penetration and schism of the optic nerve by an aneurysm are very rare. CLINICAL PRESENTATION: A 48-year-old man presented with an acute onset of right visual deterioration after an episode of severe headache. Magnetic resonance imaging demonstrated penetration of the right optic nerve by an intracranial aneurysm. Cerebral angiography revealed an internal carotid artery-ophthalmic artery aneurysm of 12 x 7 mm. The aneurysm was directed superomedially and appeared to have a "waist" within the penetration. INTERVENTION: Intraoperatively, we observed that part of the aneurysm wall was visible through the optic nerve fibers at the junction with the optic chiasm. CONCLUSION: Although there was no direct evidence of subarachnoid hemorrhage on imaging scans or with operative exploration, we think that the patient must have experienced sentinel hemorrhaging, leading to visual deterioration. We describe the case in detail and review the world literature.

Aneurysm↗
PubMed2002

Detection of microemboli by transcranial Doppler ultrasonography in aneurysmal subarachnoid hemorrhage.

OBJECTIVE: To determine the frequency and characteristics of microembolic signals (MES) in subarachnoid hemorrhage (SAH). METHODS: Twenty-three patients with aneurysmal SAH were monitored with transcranial Doppler ultrasonography for the presence of MES and vasospasm. Each middle cerebral artery was monitored for 30 minutes three times each week. Patients were excluded if they had traumatic SAH or cardiac or arterial sources of emboli. Monitoring was initiated 6.3 days (1-16 d) after SAH and lasted 6.6 days (1-13 d). Eleven individuals without SAH or other cerebrovascular diseases who were treated in the same unit served as control subjects. Each patient underwent monitoring of both middle cerebral arteries a mean of three times; therefore, 46 vessels were studied (a total of 138 observations). Control subjects underwent assessment of each middle cerebral artery once, for a total of 22 control vessels. RESULTS: MES were detected for 16 of 23 patients (70%) and 44 of 138 patient vessels (32%) monitored, compared with 2 of 11 control subjects (18%) and 2 of 22 control vessels (9%) (P < 0.05). MES were observed for 83% of patients with clinical vasospasm and 54% of those without clinical vasospasm. Ultrasonographic vasospasm was observed for 71 of 138 vessels monitored; MES were observed for 28% of vessels with vasospasm and 36% of those without vasospasm. Aneurysms proximal to the monitored artery were identified in 38 of 138 vessels, of which 34% exhibited MES, which is similar to the frequency for vessels without proximal aneurysms (31%). Coiled, clipped, and unsecured aneurysms exhibited similar frequencies of MES. CONCLUSION: MES were common in SAH, occurring in 70% of cases of SAH and one-third of all vessels monitored. Although MES were more frequent among patients with clinical vasospasm, this difference did not reach statistical significance. We were unable to demonstrate a relationship between ultrasonographic vasospasm and MES, and the presence of a proximal secured or unsecured aneurysm did not alter the chance of detection of MES. Further studies are required to determine the origin and clinical relevance of MES in SAH.

Humans↗