<p>ANOVA statistics for (A) “Total score”, p<0.001 (B) “Block I score”, p<0.001 (C) “... more <p>ANOVA statistics for (A) “Total score”, p<0.001 (B) “Block I score”, p<0.001 (C) “Block II score”, p<0.001 (D) Separately analysis of block I: “Block I score from 1<sup>st</sup> to 4<sup>th</sup> year”, p<0.001; “Block I score from 4<sup>th</sup> to 7<sup>th</sup> year”, p = 0.66.</p
In developing countries, education to health-care professionals is a cornerstone in the battle ag... more In developing countries, education to health-care professionals is a cornerstone in the battle against neglected tropical diseases (NTD). Studies evaluating the level of knowledge of medical students in clinical and socio-demographic aspects of NTD are lacking. Therefore, a cross-sectional study was conducted among students from a 7 year-curriculum medical school in Peru to assess their knowledge of NTD by using a pilot survey comprised by two blocks of 10 short questions. Block I consisted of socio-demographic and epidemiological questions whereas block II included clinical vignettes. Each correct answer had the value of 1 point. Out of 597 responders (response rate: 68.4%), 583 were considered to have valid surveys (male:female ratio: 1:1.01; mean age 21 years, SD ± 2.42). Total knowledge showed a raising trend through the 7-year curriculum. Clinical knowledge seemed to improve towards the end of medical school whereas socio-demographic and epidemiological concepts only showed progress the first 4 years of medical school, remaining static for the rest of the curricular years (p = 0.66). Higher mean scores in socio-demographic and epidemiological knowledge compared to clinical knowledge were seen in the first two years (p<0.001) whereas the last three years showed higher scores in clinical knowledge (p<0.001). In conclusion, students from this private medical school gained substantial knowledge in NTD throughout the career which seems to be related to improvement in clinical knowledge rather than to socio-demographic and epidemiological concepts. This study assures the feasibility of measuring the level of knowledge of NTD in medical students and stresses the importance of evaluating education on NTD as it may need more emphasis in epidemiological concepts, especially at developing countries such as Peru where many people are affected by these preventable and treatable diseases.
Brain metastases are the most common type of brain tumor in adults, commonly arising from primary... more Brain metastases are the most common type of brain tumor in adults, commonly arising from primary tumor sites of the lung, breast, skin (melanoma), colon, and kidney. Isolated central nervous system (CNS) metastasis arising from urothelial carcinoma (UC) is a rare presentation yielding a poor prognosis. A 71-year-old male patient with a history of urothelial carcinoma, treated one year prior with partial cystectomy and adjuvant gemcitabine and cisplatin (GC) therapy, presented with worsening neurological symptoms, including progressively worsening dizziness, shuffling gait, drifting, expressive aphasia, and confusion. MRI revealed a left frontal 4.0 x 3.6 cm brightly contrast-enhancing tumor with possible hemorrhage, extensive vasogenic edema, and moderate mass effect. An additional smaller right cerebellar lesion was also noted. Outpatient CT of his chest, abdomen, and pelvis revealed no evidence of other malignant sites. He ultimately underwent a left craniotomy with a total resection of his left frontal mass. Pathological examination revealed a urothelial primary. Post-operative MRI revealed complete resection of the left frontal mass and the patient was discharged with no neurologic deficits on exam. In many cases, brain metastases may present years later following initial therapy of UC as the CNS may act as a sanctuary site during systemic chemotherapy. Chemotherapeutics such as gemcitabine with better penetration of the blood-brain barrier may be beneficial in delaying the onset of these metastases.
Purpose: Acute subdural hematomas are frequent, highly morbid, and affect all age groups. The mos... more Purpose: Acute subdural hematomas are frequent, highly morbid, and affect all age groups. The most common mechanism of injury is a low-velocity fall, and the incidence of the disease is growing due to increasingly aggressive antithrombotic and anticoagulant therapies. In this study, we aimed to share our experience with the endoscopic-assisted evacuation of acute subdural hematoma, a less invasive procedure compared to standard craniotomy. Methods: We retrospectively reviewed data of all consecutive patients aged 18 years and older who underwent endoscopic-assisted evacuation of acute-on-chronic subdural hematoma at our institution from 2015 to 2019. Preoperative, intraoperative, postoperative, and follow-up data were collected and reported. Statistical tests were done using Python statistical packages. Results: Of the 35 patients that underwent this procedure, 32 were 18 years and older. The median age was 69.5 years and 37.5% were female. Twenty patients (62.5%) were on antiplatelet therapy, and six patients (18.75%) were on anticoagulants upon presentation. A fall was the most common cause of trauma (71.88%). The median operative time was 107 minutes. The median length of stay in days and Glasgow Coma Scale (GCS) at discharge were 8.5 and 15, respectively. There were no surgical site infections or in-hospital mortality in this series. At the latest follow-up, the median GCS and modified Rankin Scale were 15 and 1, respectively. Conclusion: Evacuation of acute-on-chronic subdural hematomas can be performed safely and efficiently via a smaller craniotomy and with the assistance of an endoscope. This may represent a less invasive alternative than standard craniotomy/craniectomy in selected patients.
BACKGROUND Multifocal rosette forming glioneuronal tumors (RGNT) are challenging to manage. Gross... more BACKGROUND Multifocal rosette forming glioneuronal tumors (RGNT) are challenging to manage. Gross total resection (GTR) is often impossible and the data on adjunctive therapies is limited. In this paper, we review cases of multifocal RGNT in the literature with special focus on dissemination patterns and management. METHODS A literature review was conducted using PubMed and the key words "(multifocal OR multicentric OR satellite OR dissemination) AND glioneuronal". RESULTS Twenty-one cases of multifocal RGNT were identified. Follow-up was available in 18 cases at a median of 17 months. The progression free survival (PFS) and overall survival (OS) at 1 year were 84% and 94%, respectively. Out of all cases, 43% had CSF dissemination, 48% had intraparenchymal spread, and 10% had both. Cases with CSF dissemination led to palliative care and/or death in 20% of cases (n = 2). None of the cases with intraparenchymal spread progressed. Radiotherapy (RT) was used in 50% of cases with CSF dissemination, chemotherapy in 20% and CSF shunting in 36%. No tumors with intraparenchymal spread required adjunctive therapy or shunting. CONCLUSION RGNTs with CSF dissemination are more likely to behave aggressively and early adjunctive therapies should be discussed with patients. Tumors with intraparenchymal spread grow slowly and maximal safe resection followed by observation is likely sufficient in the short term. Long-term behavior is still unclear.
INTRODUCTION Although statistical errors have been shown to be prevalent in the medical literatur... more INTRODUCTION Although statistical errors have been shown to be prevalent in the medical literature there has been a paucity of studies focusing on the prevalence of such errors in neurosurgery. In this article, we audit the contemporary neurosurgical literature for a common statistical mistake, namely, misinterpretations of null hypothesis significance testing results near the p-value threshold by conveying the idea of a "trend". METHODS PubMed/Medline was used to identify all articles published in six major neurosurgical journals between 2000 and 2020. The abstracts of these articles were extracted and scrutinized to determine when the word "trend" was used to express "near-statistical significance". RESULTS A total of 45,244 articles were included. Of those 461 (1.02% [0.86-1.18]) employed the word "trend" to indicate near statistical significance, a total of 3.8 [2.93-4.75] errors per issue per year. The error under study occurred more frequently in JNS Spine and less frequently in Acta Neurochirurgica (p=0.007). On an annual basis, there was no linear correlation between the total number of papers published per journal and the number of errors in that journal (r=0.34, p = 0.01). CONCLUSION Misinterpretations of null hypothesis significance testing results near the p-value threshold is present in at least 1% of the neurosurgical literature. While we believe that most statistical errors in medicine in general and neurosurgery in particular may be unintentional in nature, additional measures should be enacted to prevent the subsequent adoption of such methodological practices amongst future researchers.
Supplemental Digital Content is available in the text Object: Surgical site infection (SSI) after... more Supplemental Digital Content is available in the text Object: Surgical site infection (SSI) after cranioplasty can result in unnecessary morbidity. This analysis was designed to determine the risk factors of SSI after cranioplasty in patients who received a decompressive craniectomy with the autologous bone for traumatic brain injury (TBI). Methods: A retrospective review was performed at two level 1 academic trauma centers for adult patients who underwent autologous cranioplasty after prior decompressive craniectomy for TBI. Demographic and procedural variables were collected and analyzed for associations with an increased incidence of surgical site infection with two-sample independent t tests and Mann Whitney U tests, and with a Bonferroni correction applied in cases of multiple comparisons. Statistical significance was reported with a P value of < 0.05. Results: A total of 71 patients were identified. The mean interval from craniectomy to cranioplasty was 99 days (7–283), and 3 patients developed SSIs after cranioplasty (4.2%). Postoperative drain placement (P > 0.08) and administration of intrawound vancomycin powder (P = 0.99) were not predictive of infection risk. However, a trend was observed suggesting that administration of prophylactic preoperative IV vancomycin is associated with a reduced infection rate. Conclusions: The SSI rate after autologous cranioplasty in TBI patients is lower than previously reported for heterogeneous groups and indications, and the infection risk is comparable to other elective neurosurgical procedures. As such, the authors recommend attempting to preserve native skull and perform autologous cranioplasty in this population whenever possible.
In this initial series, we evaluated the use of microvascular decompression (MVD) under an awake ... more In this initial series, we evaluated the use of microvascular decompression (MVD) under an awake anesthesia protocol ("awake" MVD) to assess whether intraoperative pain evaluation can identify and mitigate insufficient decompression of the trigeminal nerve, improving surgical outcomes, and possibly expand the indications of MVD in patients with comorbidities that would preclude the use of general endotracheal anesthesia (GEA). An Institutional Review Board-approved prospective study of 10 consecutive adults who underwent MVD for trigeminal neuralgia (TN) was conducted. The primary outcome measure was postoperative TN pain quantified on the Barrow Neurological Institute (BNI) Pain Severity Scale. The median patient age was 65.5 years, with a female:male ratio of 6:4. All 10 patients tolerated the procedure well and did not require GEA intraoperatively or postoperatively. Nine patients had a successful surgical outcome (BNI score I, n = 5; BNI score II, n = 4). One patient d...
BACKGROUND The surgical management of supratentorial intracerebral hemorrhages (ICH) remains cont... more BACKGROUND The surgical management of supratentorial intracerebral hemorrhages (ICH) remains controversial due to large trials failing to show clear benefits. Several minimally invasive techniques have emerged as an alternative to a conventional craniotomy with promising results. OBJECTIVE To report our experience with endoport-assisted surgery in the evacuation of supratentorial ICH and its effects on outcome compared to matched medical controls. METHODS Retrospective data were gathered of patients who underwent endoport-assisted evacuation between January 2014 and October 2016 by a single surgeon. Patients who were managed medically during the same period were matched to the surgical cohort. Previously published cohorts investigating the same technique were analyzed against the present cohort. RESULTS Sixteen patients were identified and matched to 16 patients treated medically. Location, hemorrhage volume, and initial Glasgow Coma Scale (GCS) score did not differ significantly be...
Assess the potential added benefit to patient outcomes of "awake" neurological testing ... more Assess the potential added benefit to patient outcomes of "awake" neurological testing when compared with standard neurophysiologic testing performed under general endotracheal anesthesia. Prospective study of 30 consecutive adult patients who underwent awake high flow extracranial to intracranial (HFEC-IC) bypass. Clinical neurological and neurophysiologic findings were recorded. Primary outcome measures were the incidence of stroke/cerebrovascular accident (CVA), length of stay, discharge to rehabilitation, 30-day modified Rankin scale score, and death. An analysis was also performed of a retrospective control cohort (n = 110 patients who underwent HFEC-IC for internal carotid artery (ICA) aneurysms under standard general endotracheal anesthesia). Five patients (16.6%) developed clinical awake neurological changes (4, contralateral hemiparesis; 1, ipsilateral visual changes) during the 10-minute ICA occlusion test. These patients had 2 kinks in the graft, 1 vasospasm, 1 ...
<p>ANOVA statistics for (A) “Total score”, p<0.001 (B) “Block I score”, p<0.001 (C) “... more <p>ANOVA statistics for (A) “Total score”, p<0.001 (B) “Block I score”, p<0.001 (C) “Block II score”, p<0.001 (D) Separately analysis of block I: “Block I score from 1<sup>st</sup> to 4<sup>th</sup> year”, p<0.001; “Block I score from 4<sup>th</sup> to 7<sup>th</sup> year”, p = 0.66.</p
In developing countries, education to health-care professionals is a cornerstone in the battle ag... more In developing countries, education to health-care professionals is a cornerstone in the battle against neglected tropical diseases (NTD). Studies evaluating the level of knowledge of medical students in clinical and socio-demographic aspects of NTD are lacking. Therefore, a cross-sectional study was conducted among students from a 7 year-curriculum medical school in Peru to assess their knowledge of NTD by using a pilot survey comprised by two blocks of 10 short questions. Block I consisted of socio-demographic and epidemiological questions whereas block II included clinical vignettes. Each correct answer had the value of 1 point. Out of 597 responders (response rate: 68.4%), 583 were considered to have valid surveys (male:female ratio: 1:1.01; mean age 21 years, SD ± 2.42). Total knowledge showed a raising trend through the 7-year curriculum. Clinical knowledge seemed to improve towards the end of medical school whereas socio-demographic and epidemiological concepts only showed progress the first 4 years of medical school, remaining static for the rest of the curricular years (p = 0.66). Higher mean scores in socio-demographic and epidemiological knowledge compared to clinical knowledge were seen in the first two years (p<0.001) whereas the last three years showed higher scores in clinical knowledge (p<0.001). In conclusion, students from this private medical school gained substantial knowledge in NTD throughout the career which seems to be related to improvement in clinical knowledge rather than to socio-demographic and epidemiological concepts. This study assures the feasibility of measuring the level of knowledge of NTD in medical students and stresses the importance of evaluating education on NTD as it may need more emphasis in epidemiological concepts, especially at developing countries such as Peru where many people are affected by these preventable and treatable diseases.
Brain metastases are the most common type of brain tumor in adults, commonly arising from primary... more Brain metastases are the most common type of brain tumor in adults, commonly arising from primary tumor sites of the lung, breast, skin (melanoma), colon, and kidney. Isolated central nervous system (CNS) metastasis arising from urothelial carcinoma (UC) is a rare presentation yielding a poor prognosis. A 71-year-old male patient with a history of urothelial carcinoma, treated one year prior with partial cystectomy and adjuvant gemcitabine and cisplatin (GC) therapy, presented with worsening neurological symptoms, including progressively worsening dizziness, shuffling gait, drifting, expressive aphasia, and confusion. MRI revealed a left frontal 4.0 x 3.6 cm brightly contrast-enhancing tumor with possible hemorrhage, extensive vasogenic edema, and moderate mass effect. An additional smaller right cerebellar lesion was also noted. Outpatient CT of his chest, abdomen, and pelvis revealed no evidence of other malignant sites. He ultimately underwent a left craniotomy with a total resection of his left frontal mass. Pathological examination revealed a urothelial primary. Post-operative MRI revealed complete resection of the left frontal mass and the patient was discharged with no neurologic deficits on exam. In many cases, brain metastases may present years later following initial therapy of UC as the CNS may act as a sanctuary site during systemic chemotherapy. Chemotherapeutics such as gemcitabine with better penetration of the blood-brain barrier may be beneficial in delaying the onset of these metastases.
Purpose: Acute subdural hematomas are frequent, highly morbid, and affect all age groups. The mos... more Purpose: Acute subdural hematomas are frequent, highly morbid, and affect all age groups. The most common mechanism of injury is a low-velocity fall, and the incidence of the disease is growing due to increasingly aggressive antithrombotic and anticoagulant therapies. In this study, we aimed to share our experience with the endoscopic-assisted evacuation of acute subdural hematoma, a less invasive procedure compared to standard craniotomy. Methods: We retrospectively reviewed data of all consecutive patients aged 18 years and older who underwent endoscopic-assisted evacuation of acute-on-chronic subdural hematoma at our institution from 2015 to 2019. Preoperative, intraoperative, postoperative, and follow-up data were collected and reported. Statistical tests were done using Python statistical packages. Results: Of the 35 patients that underwent this procedure, 32 were 18 years and older. The median age was 69.5 years and 37.5% were female. Twenty patients (62.5%) were on antiplatelet therapy, and six patients (18.75%) were on anticoagulants upon presentation. A fall was the most common cause of trauma (71.88%). The median operative time was 107 minutes. The median length of stay in days and Glasgow Coma Scale (GCS) at discharge were 8.5 and 15, respectively. There were no surgical site infections or in-hospital mortality in this series. At the latest follow-up, the median GCS and modified Rankin Scale were 15 and 1, respectively. Conclusion: Evacuation of acute-on-chronic subdural hematomas can be performed safely and efficiently via a smaller craniotomy and with the assistance of an endoscope. This may represent a less invasive alternative than standard craniotomy/craniectomy in selected patients.
BACKGROUND Multifocal rosette forming glioneuronal tumors (RGNT) are challenging to manage. Gross... more BACKGROUND Multifocal rosette forming glioneuronal tumors (RGNT) are challenging to manage. Gross total resection (GTR) is often impossible and the data on adjunctive therapies is limited. In this paper, we review cases of multifocal RGNT in the literature with special focus on dissemination patterns and management. METHODS A literature review was conducted using PubMed and the key words "(multifocal OR multicentric OR satellite OR dissemination) AND glioneuronal". RESULTS Twenty-one cases of multifocal RGNT were identified. Follow-up was available in 18 cases at a median of 17 months. The progression free survival (PFS) and overall survival (OS) at 1 year were 84% and 94%, respectively. Out of all cases, 43% had CSF dissemination, 48% had intraparenchymal spread, and 10% had both. Cases with CSF dissemination led to palliative care and/or death in 20% of cases (n = 2). None of the cases with intraparenchymal spread progressed. Radiotherapy (RT) was used in 50% of cases with CSF dissemination, chemotherapy in 20% and CSF shunting in 36%. No tumors with intraparenchymal spread required adjunctive therapy or shunting. CONCLUSION RGNTs with CSF dissemination are more likely to behave aggressively and early adjunctive therapies should be discussed with patients. Tumors with intraparenchymal spread grow slowly and maximal safe resection followed by observation is likely sufficient in the short term. Long-term behavior is still unclear.
INTRODUCTION Although statistical errors have been shown to be prevalent in the medical literatur... more INTRODUCTION Although statistical errors have been shown to be prevalent in the medical literature there has been a paucity of studies focusing on the prevalence of such errors in neurosurgery. In this article, we audit the contemporary neurosurgical literature for a common statistical mistake, namely, misinterpretations of null hypothesis significance testing results near the p-value threshold by conveying the idea of a "trend". METHODS PubMed/Medline was used to identify all articles published in six major neurosurgical journals between 2000 and 2020. The abstracts of these articles were extracted and scrutinized to determine when the word "trend" was used to express "near-statistical significance". RESULTS A total of 45,244 articles were included. Of those 461 (1.02% [0.86-1.18]) employed the word "trend" to indicate near statistical significance, a total of 3.8 [2.93-4.75] errors per issue per year. The error under study occurred more frequently in JNS Spine and less frequently in Acta Neurochirurgica (p=0.007). On an annual basis, there was no linear correlation between the total number of papers published per journal and the number of errors in that journal (r=0.34, p = 0.01). CONCLUSION Misinterpretations of null hypothesis significance testing results near the p-value threshold is present in at least 1% of the neurosurgical literature. While we believe that most statistical errors in medicine in general and neurosurgery in particular may be unintentional in nature, additional measures should be enacted to prevent the subsequent adoption of such methodological practices amongst future researchers.
Supplemental Digital Content is available in the text Object: Surgical site infection (SSI) after... more Supplemental Digital Content is available in the text Object: Surgical site infection (SSI) after cranioplasty can result in unnecessary morbidity. This analysis was designed to determine the risk factors of SSI after cranioplasty in patients who received a decompressive craniectomy with the autologous bone for traumatic brain injury (TBI). Methods: A retrospective review was performed at two level 1 academic trauma centers for adult patients who underwent autologous cranioplasty after prior decompressive craniectomy for TBI. Demographic and procedural variables were collected and analyzed for associations with an increased incidence of surgical site infection with two-sample independent t tests and Mann Whitney U tests, and with a Bonferroni correction applied in cases of multiple comparisons. Statistical significance was reported with a P value of < 0.05. Results: A total of 71 patients were identified. The mean interval from craniectomy to cranioplasty was 99 days (7–283), and 3 patients developed SSIs after cranioplasty (4.2%). Postoperative drain placement (P > 0.08) and administration of intrawound vancomycin powder (P = 0.99) were not predictive of infection risk. However, a trend was observed suggesting that administration of prophylactic preoperative IV vancomycin is associated with a reduced infection rate. Conclusions: The SSI rate after autologous cranioplasty in TBI patients is lower than previously reported for heterogeneous groups and indications, and the infection risk is comparable to other elective neurosurgical procedures. As such, the authors recommend attempting to preserve native skull and perform autologous cranioplasty in this population whenever possible.
In this initial series, we evaluated the use of microvascular decompression (MVD) under an awake ... more In this initial series, we evaluated the use of microvascular decompression (MVD) under an awake anesthesia protocol ("awake" MVD) to assess whether intraoperative pain evaluation can identify and mitigate insufficient decompression of the trigeminal nerve, improving surgical outcomes, and possibly expand the indications of MVD in patients with comorbidities that would preclude the use of general endotracheal anesthesia (GEA). An Institutional Review Board-approved prospective study of 10 consecutive adults who underwent MVD for trigeminal neuralgia (TN) was conducted. The primary outcome measure was postoperative TN pain quantified on the Barrow Neurological Institute (BNI) Pain Severity Scale. The median patient age was 65.5 years, with a female:male ratio of 6:4. All 10 patients tolerated the procedure well and did not require GEA intraoperatively or postoperatively. Nine patients had a successful surgical outcome (BNI score I, n = 5; BNI score II, n = 4). One patient d...
BACKGROUND The surgical management of supratentorial intracerebral hemorrhages (ICH) remains cont... more BACKGROUND The surgical management of supratentorial intracerebral hemorrhages (ICH) remains controversial due to large trials failing to show clear benefits. Several minimally invasive techniques have emerged as an alternative to a conventional craniotomy with promising results. OBJECTIVE To report our experience with endoport-assisted surgery in the evacuation of supratentorial ICH and its effects on outcome compared to matched medical controls. METHODS Retrospective data were gathered of patients who underwent endoport-assisted evacuation between January 2014 and October 2016 by a single surgeon. Patients who were managed medically during the same period were matched to the surgical cohort. Previously published cohorts investigating the same technique were analyzed against the present cohort. RESULTS Sixteen patients were identified and matched to 16 patients treated medically. Location, hemorrhage volume, and initial Glasgow Coma Scale (GCS) score did not differ significantly be...
Assess the potential added benefit to patient outcomes of "awake" neurological testing ... more Assess the potential added benefit to patient outcomes of "awake" neurological testing when compared with standard neurophysiologic testing performed under general endotracheal anesthesia. Prospective study of 30 consecutive adult patients who underwent awake high flow extracranial to intracranial (HFEC-IC) bypass. Clinical neurological and neurophysiologic findings were recorded. Primary outcome measures were the incidence of stroke/cerebrovascular accident (CVA), length of stay, discharge to rehabilitation, 30-day modified Rankin scale score, and death. An analysis was also performed of a retrospective control cohort (n = 110 patients who underwent HFEC-IC for internal carotid artery (ICA) aneurysms under standard general endotracheal anesthesia). Five patients (16.6%) developed clinical awake neurological changes (4, contralateral hemiparesis; 1, ipsilateral visual changes) during the 10-minute ICA occlusion test. These patients had 2 kinks in the graft, 1 vasospasm, 1 ...
Uploads
Papers by Jorge Urquiaga