Juan Gómez-amador - Academia.edu (original) (raw)

Papers by Juan Gómez-amador

Cureus, Jan 12, 2022

Collision tumors are rare neoplasms composed of two different types of histological tissues in th... more Collision tumors are rare neoplasms composed of two different types of histological tissues in the same organ. The most frequent association with cerebral cavernous malformations (CCMs) are meningiomas, gliomas, and gangliogliomas, while the most frequent sellar collision is between pituitary adenoma (PA) and craniopharyngiomas, and still very few cases have been reported. We present the case of a 43-year-old woman who started two months ago with a fall from her height followed by severe headache and bilateral hemianopsia. An isointense, enhancing sellar tumor, and a right frontal lesion compatible with CCM were observed on MRI. Surgery was performed through anterior interhemispheric and endoscopic transnasal approaches for the cavernoma and the sellar tumor, respectively, removing both lesions and sending them to pathology. The sellar tumor corresponded to a PA showing positive immunohistochemistry for prolactin and follicle-stimulating hormone (FSH). In the post-op period, the patient developed a seizure and diabetes insipidus, for which she received appropriate treatment. Our findings were conclusive with a collision tumor, since both lesions presented two different histological tissues. Different densities were observed in both lesions using imaging studies, which were later confirmed with histopathology and immunohistochemistry.

Journal of Neuro-oncology, Feb 16, 2018

Gliomas are the most common primary intrinsic tumor in the brain and are classified as low-or hig... more Gliomas are the most common primary intrinsic tumor in the brain and are classified as low-or high-grade according to the World Health Organization (WHO). Patients with high-grade gliomas (HGG) who undergo surgical resection with adjuvant therapy have a mean overall survival of 15 months and 100% recurrence. The renin-angiotensin system (RAS), the primary regulator of cardiovascular circulation, exhibits local action and works as a paracrine system. In the context of this local regulation, the expression of RAS peptides and receptors has been detected in different kinds of tumors, including gliomas. The dysregulation of RAS components plays a significant role in the proliferation, angiogenesis, and invasion of these tumors, and therefore in their outcomes. The study and potential application of RAS peptides and receptors as biomarkers in gliomas could bring advantages against the limitations of current tumoral markers and should be considered in the future. The targeting of RAS components by RAS blockers has shown potential of being protective against cancer and improving immunotherapy. In gliomas, RAS blockers have shown a broad spectrum for beneficial effects and are being considered for use in treatment protocols. This review aims to summarize the background behind how RAS plays a role in gliomagenesis and explore the evidence that could lead to their use as biomarkers and treatment adjuvants.

Journal of Clinical Neuroscience, Nov 1, 2019

Introduction: Vertigo is a common condition occurring in the general population and is usually se... more Introduction: Vertigo is a common condition occurring in the general population and is usually selflimited. Reports studying vertigo in patients with brain metastasis (BM), are scarce. Therefore, the aim of this study was to analyze if the presence of vertigo in cancer patients is associated with the presence of BM. Methods: This study was conducted in a cancer referral center, where patients with confirmed systemic cancer sent for a neuro-oncologic consultation from May 2012 to March 2018 were included for review. Results: Of 3220 patients, 723 were diagnosed with BM, and 204 had vertigo. Of these patients, 22.5% of those who had vertigo were diagnosed to have BM and 6% of those with BM had vertigo as an initial symptom (odds ratio [OR] 0.9; p = 0.9). An additional symptom was present in 104 patients with vertigo. Bivariate regression analysis disclosed a higher risk of having BM in patients with vertigo accompanied by headache (OR18.6; p < 0.0001), ataxia (OR12.1; p < 0.0001), seizures (OR10.9; p = 0.04), visual symptoms (OR10.4; p < 0.0001), speech impairment (OR6.3; p = 0.01), altered mental status (OR7.4; p < 0.0001), and focal weakness (OR7.4; p = 0.001), or focal sensitive complaint (OR6.9; p = 0.003). Vertigo with headache or ataxia remained statistically significant after multivariate analysis. Conclusion: In this cohort, a higher risk of having BM was associated with the presence of vertigo coexistent with headache, ataxia, seizures, visual symptoms, speech impairment, altered mental status, focal weakness, or focal sensitive complaint. On the basis of these results, these accompanying symptoms must be considered as red flags in patients with systemic cancer.

Neurosurgical Review, May 28, 2016

According to the International Agency for Research Cancer, of the 10.9 million people diagnosed w... more According to the International Agency for Research Cancer, of the 10.9 million people diagnosed with cancer all around the world every year, approximately 50 % require radiotherapy, with 60 % of them being treated with curative intention (meaning high doses of radiation) [1]. Cranial radiation exposure is not uncommon in daily medical practice, and it represents a challenge when the patient needs to be treated with neurosurgical procedures. Radiation damage has recently been pointed out to be a result of apoptosis in the sphingomyelin pathway [2], and through histopathological studies, the main damage has been tracked to the endothelium microvasculature; this leads to subsequent disruption of the blood–brain barrier and the thickening and hyalinization of the vessel wall, and it is important to mention that this radiation-induced injury reflects to all tissues exposed to the radiation field, being most affected the superficial layers near the radiation beam. Although it is generally accepted that normal tissue damage is a dynamic and progressive process, it cannot be established a specific narrow interval in which histopathological changes are developed, mostly because these depend on several variables that involve physics factors (total dose, volume irradiated), patient characteristics (age, history of smoking, diabetes, hypertension), and even chance (Poisson statistics) [3]. The final outcome is represented by the rates of healing process, ischemic strokes, and microbleeds that may occur months to years after radiation exposure [3]. Other studies have shown an increased likelihood of cerebrospinal fluid (CSF) leakage and local infection in previously irradiated dura [4, 5]. Therefore, in the scenario of increased likelihood of healing process failure with imminent subsequent complications that a previous irradiated tissue represents, we must find an alternative to achieve an appropriate closure in one of the most important steps in all neurosurgical procedures: dural repair. Considering that in a great percentage of cases, no dural defect needs to be repaired, we focused on the most common radiation-induced intracranial lesion: secondary meningioma [6–10], where a gross-total resection with the minimum risk of recurrence is represented by a Simpson-grade 0 surgical resection, which implies the resection of two additional centimeters of marginal non-infiltrated peripheral dura, therefore always creating a dural defect to be repaired. Of course, we must bear in mind that any surgical procedure could potentially end requiring some dural repair, an issue not always considered at surgical planning, so alternatives should be well-known while treating patients with previous radiation exposure. Several authors [11–13] have reported additional benefits of using a vascularized pericranial flap (VPF) for the reconstruction of dural defects, mostly in neurosurgical * Hector Sebastián Velasco-Torres hsvtorres@gmail.com

Brain Sciences, Apr 28, 2023

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

World Neurosurgery, Feb 1, 2022

The surgical management of lesions within or around the brainstem is usually associated with sign... more The surgical management of lesions within or around the brainstem is usually associated with significant morbidity. Even though several safe entry zones have been described for brainstem lesions, especially cavernous malformations (CMs), their resection remains a challenge due to the convergence of highly functional nerve tracts and nuclei in this rather small structure. Moreover, the ventral location of some of these lesions usually calls for complex surgical approaches involving extensive bone drilling and significant manipulation of neurovascular structures. The expanded endoscopic endonasal approach has been subject to considerable advancements, widening the range of lesions accessible through this route. In this operative video, we describe the surgical nuances of an endoscopic endonasal transclival resection of a ventral pontine CM (Figure 1-2). A pedicled nasoseptal flap was harvested for reconstruction, gaining access to the sphenoid rostrum, which was resected. The sellar floor was removed to expose the middle third of the clivus, which was drilled out until posterior fossa dura mater was identified. A centered dural incision was performed to expose the ventral pons and the basilar artery. Using image-guidance, a limited pial incision over the most superficial aspect of the lesion allowed a prompt drainage of the hematoma and resection of the CM. The surgical cavity was directly inspected through the endoscope, confirming a complete resection. Reconstruction was carried out in a multi-layered fashion. The patient presented a postoperative CSF leak, which resolved with a lumbar drain. Neurologic status remained unchanged after surgery, with the patient displaying a favorable clinical outcome.

Annals of Vascular Surgery, 2017

Persistent trigeminal artery (PTA), also called primitive trigeminal artery, represents the most ... more Persistent trigeminal artery (PTA), also called primitive trigeminal artery, represents the most common embryonic remnant of fetal circulation in adulthood, (only after fetal pattern of posterior communicating artery [PComA]) with an estimated incidence of between 0.1% and 0.76%. The permanence of this fetal pattern constitutes an incidental finding in most cases, however, may be associated with aneurysms, arteriovenous malformations, trigeminal neuralgia, and other types of fetal circulation persistency. A patient with giant aneurysm in the communicating segment of the right internal carotid artery, associated with the presence of PTA and fetal pattern of PComA, also on the right side is reported.

Journal of Clinical Monitoring and Computing, Sep 1, 2016

This paper reports the case of a patient with optic nerve schwannoma and the first use of neuroph... more This paper reports the case of a patient with optic nerve schwannoma and the first use of neurophysiological intraoperative monitoring of visual evoked potentials during the removal of such tumor with no postoperative visual damage. Schwannomas are benign neoplasms of the peripheral nervous system arising from the neural crest-derived Schwann cells, these tumors are rarely located in the optic nerve and the treatment consists on surgical removal leading to high risk of damage to the visual pathway. Case report of a thirty-year-old woman with an optic nerve schwannoma. The patient underwent surgery for tumor removal on the left optic nerve through a left orbitozygomatic approach with intraoperative monitoring of left II and III cranial nerves. We used Nicolet Endeavour CR IOM (Carefusion, Middleton WI, USA) to performed visual evoked potentials stimulating binocularly with LED flash goggles with the patient´s eyes closed and direct epidural optic nerve stimulation delivering rostral to the tumor a rectangular current pulse. At follow up examinations 7 months later, the left eye visual acuity was 20/60; Ishihara score was 8/8 in both eyes; the right eye photomotor reflex was normal and left eye was mydriatic and arreflectic; optokinetic reflex and ocular conjugate movements were normal. In this case, the epidural direct electrical stimulation of optic nerve provided stable waveforms during optic nerve schwannoma resection without visual loss.

Surgical Neurology International, 2017

Background: Intraventricular cavernous malformations are unusual intracranial vascular malformati... more Background: Intraventricular cavernous malformations are unusual intracranial vascular malformations; their deep anatomical location complicates their surgical management. Microsurgical approaches are the gold standard approaches for the resection of ventricular lesions, however, they imply considerable neurovascular risks. Case Description: A 51-year-old patient presented with acute headache, diplopia, vertigo, blurred vision, and a depressed level of consciousness. A ventricular hemorrhage was treated with a ventriculostomy and the patient was discharged without hydrocephalus. After 11 days, he developed ataxia, diplopia, and a depressed level of consciousness. The patient was diagnosed with hydrocephalus secondary to the previous third ventricle hemorrhage. An endoscopic exploration using a 30° rigid ventricular endoscope was performed; after the third ventriculostomy, an intraventricular cavernous malformation located on the floor of the third ventricle and the aqueduct of Sylvius was resected. Conclusions: Three days after the surgery, magnetic resonance imaging demonstrated a gross total resection and adequate third ventriculostomy flow. One year after the surgery, the patient was asymptomatic. Neuroendoscopy has evolved towards minimally invasiveness, and in selected cases is an equally effective surgical approach to ventricular lesions. It provides minimal cerebral cortex disruption and vascular manipulation.

Archivos de Neurociencias, Jan 29, 2023

It is important to understand the patient's vascular anatomy before treating cerebral aneurysms. ... more It is important to understand the patient's vascular anatomy before treating cerebral aneurysms. The middle artery of the corpus callosum is one of the least common variations of the anterior communicating artery (AComA) complex. We describe the case of a 59-year-old woman who suffered a subarachnoid hemorrhage due to an AComA complex aneurysm that had ruptured. Fluorescein injection during the aneurysm clipping procedure revealed a partial obstruction of the middle artery, requiring clip repositioning. The vascular variations that patients may exhibit must be considered in aneurysm clipping surgery.

World Neurosurgery, Jul 1, 2023

Archivos de neurociencias, Nov 30, 2021

Background: Alveolar soft part sarcoma (ASPS) is a rare, slow-growing soft tissue tumor with unce... more Background: Alveolar soft part sarcoma (ASPS) is a rare, slow-growing soft tissue tumor with uncertain etiology; it is considered among the least common sarcomas, representing 0.2-1% of these cases in large studies. These tumors usually appear during childhood or young patients, with predominance in females. Case description: We introduce the case of an ASPS in a 62-year-old man, who presented with 7 months of progressive headache and diplopia. MRI showed an infiltrative lesion in the anterior fossa that extended to the right orbital roof. Metastases were ruled out. The patient underwent resection of the tumor with good visual and neurologic recovery. Histologic characterization showed a pattern of homogeneous eosinophilic cells with a solid and vascularized pattern; cells with large and binucleated nucleoli; vessels with endothelial and myoepithelial hyperplasia; numerous apoptotic bodies and mitotic figures were also present, but no necrosis was found. On immunohistochemistry, cells exhibited positivity to CD56, membranous NSE, and slight myogenin reactivity; vessels were strongly positive for myogenin, myoglobin, CD34, CD31, factor VIII, vimentin, and nestin as well as for HBM45, CD20, GFAP, and S-100; cytokeratin showed fine extracellular and intracellular filaments; GATA and TTF1 were negative. Some clear cells were observed to be positive for CD68. The piece was diagnosed as a non-meningeal alveolar sarcoma of soft tissues with a solid pattern. Discussion and conclusion: This case corresponds to the second tumor of this kind presented at our institution, the first one reported, and perhaps, one of the oldest patients to develop it worldwide.

Archivos - Instituto nacional de neurología y neurocirugía, Jun 1, 2015

Artículo de revisión RESUMEN La determinación de muerte encefálica (ME) es una de las situaciones... more Artículo de revisión RESUMEN La determinación de muerte encefálica (ME) es una de las situaciones más difíciles con las que puede enfrentarse un médico a lo largo de su práctica profesional, no sólo por lo complejo de la exploración neurológica, con la que a menudo no está familiarizado, sino por todo lo que implica declarar que una persona ha dejado de vivir. Se realizó una revisión de las últimas guías en lo que concierne al diagnóstico de muerte encefálica (ME) tanto en pacientes pediátricos como en adultos, incluimos métodos auxiliares, movimientos que pueden estar presentes en estos pacientes y cuadros prácticos con el objetivo de apoyar con esta herramienta a los médicos de cualquier especialidad en caso de que se encuentren ante un paciente con ME.

Journal of Cerebrovascular and Endovascular Neurosurgery, Jan 3, 2023

Intracranial aneurysms arise in 1-2% of the population and usually present as hemorrhagic strokes... more Intracranial aneurysms arise in 1-2% of the population and usually present as hemorrhagic strokes. Spontaneous thrombosis of a ruptured intracranial aneurysm occurs in 1-3% and most commonly in giant aneurysms, with complete thrombosis in just 13-20% of the cases. Thrombosis of smaller aneurysms is rare. Here we present a case of a patient who presented with a ruptured intracranial aneurysm that subsequently thrombosed, discovering a neighboring de-novo aneurysm during follow-up. We hypothesized that after thrombosis, the hemodynamic characteristics that contributed to the formation of the first aneurysm were replicated.

Surgical Neurology International, Jan 27, 2023

is is an open-access article distributed under the terms of the Creative Commons Attribution-Non... more is is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, transform, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.

International Journal of Surgery Case Reports, 2018

BACKGROUND: McCune-Albright's syndrome (MAS) is a rare disorder that is characterized by café-au-... more BACKGROUND: McCune-Albright's syndrome (MAS) is a rare disorder that is characterized by café-au-lait macules, fibrous dysplasia of the skull and endocrinopathies like excessive secretion of growth hormone by a hyper-functional pituitary adenoma (PA). CASE: We describe the case of a 43-year-old male with history of Gigantism in 1990 secondary to a GH-secreting pituitary macroadenoma that was treated via microscopic transsphenoidal surgery at that time. He was reported as asymptomatic for 26 years until he developed headache and right temporal hemianopia with left amaurosis. Also ptosis and proptosis was found caused by a re-growth of the tumor on the follow up MRI. A second surgical procedure was performed via a dorsolateral craniotomy. Gross total resection was also achieved with a Neuropathology report of a pituitary adenoma tissue accompanied by extended dystrophic calcification and bone formation. CONCLUSION: This is a rare case of MAS. Gigantism within the context of a pituitary calcification raises special diagnostic and therapeutic challenges. The cause of the excessive secretion of GH in MAS is not well understood concluding that it seems to be a different etiology of patients with Acromegaly and Gigantism in non-MAS patients.

Pituitary, Sep 12, 2020

Background The type of sellar barrier observed between a pituitary tumor and cerebrospinal fluid ... more Background The type of sellar barrier observed between a pituitary tumor and cerebrospinal fluid (CSF) on preoperative magnetic resonance imaging (MRI) may predict intraoperative CSF leak during endonasal pituitary surgery. This is the first multicentric prospective cohort trial to study the sellar barrier concept and CSF leak rate during endoscopic pituitary surgery. Methods This multi-center, international study enrolled patients operated for pituitary adenomas via fully endoscopic endonasal surgery over a period of 4 months. The independent variable was the subtype of sellar barrier observed on preoperative MRI (strong, mixed or weak); the dependent variable was the presence of an intraoperative CSF leak. The primary goal was to determine the association between a particular type of sellar barrier and the risk of intraoperative CSF leak. Appropriate statistical methods were then applied for data analysis. Results Over the study period, 310 patients underwent endoscopic endonasal surgery for pituitary tumor. Preoperative imaging revealed a weak sellar barrier in 73 (23.55%), a mixed sellar barrier in 75 (24.19%), and a strong sellar barrier in 162 (52.26%) patients. The overall rate of intraoperative CSF leak among all patients was 69 (22.26%). A strong sellar-type barrier was associated with significantly reduced rate of intraoperative CSF leak (RR = 0.08; 95% CI 0.03-0.19; p < 0.0001), while a weak sellar barrier associated with higher rates of CSF leak (RR = 8.54; 95% CI 5.4-13.5; p < 0.0001). Conclusions The preoperative MRI of pituitary patients can suggest intraoperative CSF leak rates, utilizing the concept of the sellar barrier. Patients with a weak sellar barrier carry a higher risk for an intraoperative CSF leak, whereas a strong sellar barrier on MRI seems to mitigate intraoperative CSF leak. We propose that preoperatively assessment of the sellar barrier can prepare surgeons for intraoperative CSF leak repair.

Operative Neurosurgery, Jul 13, 2018

BACKGROUND Due to the critical neurovascular structures that surround the pulvinar, deciding the ... more BACKGROUND Due to the critical neurovascular structures that surround the pulvinar, deciding the best surgical approach can be challenging, with multiple options available. OBJECTIVE To analyze and compare the ipsilateral vs the contralateral version of the 2 main approaches to the cisternal pulvinar surface: paramedian supracerebellar infratentorial (PSCI) and interhemispheric occipital transtentorial (IOT). METHODS The PSCI and IOT approaches were performed on 7 formalin-fixed adult cadaveric heads to evaluate qualitatively and quantitatively the microsurgical exposure of relevant anatomic structures. We quantitatively measured the corridor distance to our target with each approach. RESULTS The ipsilateral PSCI approach provided an easier access and a better exposure of the anteromedial portion of the cisternal pulvinar surface. The contralateral approach provided a wider and more accessible exposure of the posterolateral portion of the cisternal pulvinar surface. When protrusion of the posterior parahippocampal gyrus above the free edge of the tentorium was present, the contralateral PSCI approach provided an unobstructed view to both areas. The IOT approach provided a better view of the anteromedial portion of the cisternal pulvinar surface, especially with a contralateral approach. CONCLUSION Multiple approaches to the pulvinar have been described, modified, and improved. Based on this anatomic study we believe that although the corridor distance with a contralateral approach is longer, the surgical view and access can be better. We recommend the use of a PSCI contralateral approach especially when a significant protrusion of the posterior parahippocampal gyrus is present.

Journal of Cerebrovascular and Endovascular Neurosurgery

Objective: To describe the roadmapping technique and our three-year experience in the management ... more Objective: To describe the roadmapping technique and our three-year experience in the management of intracranial aneurysms in the hybrid operating room.Methods: We analyzed all patients who underwent surgical clipping for cerebral aneurysms with the roadmapping technique from January 2017 to September 2019. We report demographic, clinical, and morphological variables, as well as clinical and radiological outcomes. We further describe three illustrative cases of the technique.Results: A total of 13 patients were included, 9 of which (69.2%) presented with subarachnoid hemorrhage, with a total of 23 treated aneurysms. All patients were female, with a mean age of 47.7 years (range 31-63). All cases were anterior circulation aneurysms, the most frequent location being the ophthalmic segment of the internal carotid artery (ICA) in 11 cases (48%), followed by posterior communicating in 8 (36%), and ICA bifurcation in 2 (8%). Intraoperative clip repositioning was required in 9 aneurysms (3...