The authors describe a patient with delayed thoracic spinal cord compression due to fibrous scar tissue around an epidural electrode used in spinal cord stimulation (SCS). One year after implantation of the system the stimulation became ineffective, and 1 year later the patient developed progressive paraparesis. There was no evidence of device-related complications on plain radiographs and CT scans, so the system was removed to perform MRI studies. These studies showed a dorsal myelopathy secondary to scar tissue around the electrode. At surgery thick scar tissue was resected, and the patient's neurological symptoms improved. The histological examination confirmed fibrosis, and microbiological studies excluded chronic infection. As far as the authors are aware, this complication has never been reported before at the thoracic level. Scarring around SCS electrodes should be considered as a late complication and as a possible cause of the tolerance phenomenon.
Marta Cicuendez, Pablo M. Munarriz, Ana M. Castaño-Leon, and Igor Paredes
Luis Jiménez-Roldán, Jose F. Alén, Pedro A. Gómez, Ramiro D. Lobato, Ana Ramos, Pablo M. Munarriz, and Alfonso Lagares
There were two main purposes to this study: first, to assess the feasibility and reliability of 2 quantitative methods to assess bleeding volume in patients who suffered spontaneous subarachnoid hemorrhage (SAH), and second, to compare these methods to other qualitative and semiquantitative scales in terms of reliability and accuracy in predicting delayed cerebral ischemia (DCI) and outcome.
A prospective series of 150 patients consecutively admitted to the Hospital 12 de Octubre over a 4-year period were included in the study. All of these patients had a diagnosis of SAH, and diagnostic CT was able to be performed in the first 24 hours after the onset of the symptoms. All CT scans were evaluated by 2 independent observers in a blinded fashion, using 2 different quantitative methods to estimate the aneurysmal bleeding volume: region of interest (ROI) volume and the Cavalieri method. The images were also graded using the Fisher scale, modified Fisher scale, Claasen scale, and the semiquantitative Hijdra scale. Weighted κ coefficients were calculated for assessing the interobserver reliability of qualitative scales and the Hijdra scores. For assessing the intermethod and interrater reliability of volumetric measurements, intraclass correlation coefficients (ICCs) were used as well as the methodology proposed by Bland and Altman. Finally, weighted κ coefficients were calculated for the different quartiles of the volumetric measurements to make comparison with qualitative scales easier. Patients surviving more than 48 hours were included in the analysis of DCI predisposing factors and analyzed using the chi-square or the Mann-Whitney U-tests. Logistic regression analysis was used for predicting DCI and outcome in the different quartiles of bleeding volume to obtain adjusted ORs. The diagnostic accuracy of each scale was obtained by calculating the area under the receiver operating characteristic curve (AUC).
Qualitative scores showed a moderate interobserver reproducibility (weighted κ indexes were always < 0.65), whereas the semiquantitative and quantitative scores had a very strong interobserver reproducibility. Reliability was very high for all quantitative measures as expressed by the ICCs for intermethod and interobserver agreement. Poor outcome and DCI occurred in 49% and 31% of patients, respectively. Larger bleeding volumes were related to a poorer outcome and a higher risk of developing DCI, and the proportion of patients suffering DCI or a poor outcome increased with each quartile, maintaining this relationship after adjusting for the main clinical factors related to outcome. Quantitative analysis of total bleeding volume achieved the highest AUC, and had a greater discriminative ability than the qualitative scales for predicting the development of DCI and outcome.
The use of quantitative measures may reduce interobserver variability in comparison with categorical scales. These measures are feasible using dedicated software and show a better prognostic capability in relation to outcome and DCI than conventional categorical scales.
Newton Cho, Vincent D. W. Nga, Raheel Ahmed, Jerry C. Ku, Pablo M. Munarriz, Prakash Muthusami, James T. Rutka, and Peter Dirks
Pediatric rolandic arteriovenous malformations (AVMs) present a treatment challenge given the lifetime risk of hemorrhage, rehemorrhage, and associated long-term morbidity. Microsurgical resection has been recommended as the optimal treatment for AVMs in general, but there is no dedicated literature on the outcomes of resection of pediatric rolandic AVMs. Here, the study objective was to review the outcomes of microsurgical resection of pediatric rolandic AVMs in the modern era, together with the utilization of surgical adjuncts including navigation, intraoperative angiography, and neurophysiological monitoring.
The authors performed a retrospective review of patients 18 years of age and younger with cerebral AVMs microsurgically treated between January 2000 and May 2016 at The Hospital for Sick Children. Only those patients with an AVM whose nidus was located within the rolandic region were analyzed. A descriptive analysis was performed to identify patient demographics, preoperative AVM characteristics, and postoperative obliteration rates and neurological complications.
A total of 279 AVMs were evaluated in the study period. Twenty-three of these AVMs were rolandic, and the median age in the 11 microsurgically treated cases was 11 years (range 1–17 years). AVM hemorrhage was the most common presentation, occurring in 8 patients (73%). Lesions were either Spetzler-Martin grade II (n = 8, 73%) or grade III (n = 3, 27%). The postoperative obliteration rate of AVMs was 100%. The mean imaging follow-up duration was 33 months (range 5–164 months). There was no documented recurrence of an AVM during follow-up. One patient developed a transient postoperative hemiparesis, while another patient developed right fingertip hyperesthesia.
Microsurgical resection of rolandic pediatric AVMs yields excellent AVM obliteration with minimal neurological morbidity in selected patients. The incorporation of surgical adjuncts, including neurophysiological monitoring and neuronavigation, allows accurate demarcation of functional cortex and enables effective resection.
Santiago Cepeda, Ana María Castaño-León, Pablo M. Munarriz, Igor Paredes, Irene Panero, Carla Eiriz, Pedro A. Gómez, and Alfonso Lagares
Traumatic intracerebral hemorrhage (TICH) represents approximately 13%–48% of the lesions after a traumatic brain injury (TBI), and hemorrhagic progression (HP) occurs in 38%–63% of cases. In previous studies, decompressive craniectomy (DC) has been characterized as a risk factor in the HP of TICH; however, few studies have focused exclusively on this relationship. The object of the present study was to analyze the relationship between DC and the growth of TICH and to reveal any correlation with the size of the craniectomy, degree of cerebral parenchymal herniation (CPH), or volumetric expansion of the TICH.
The authors retrospectively analyzed the records of 497 adult patients who had been consecutively admitted after suffering a severe or moderate closed TBI. An inclusion criterion was presentation with one or more TICHs on the initial or control CT. Demographic, clinical, radiological, and treatment variables were assessed for associations.
Two hundred three patients presenting with 401 individual TICHs met the selection criteria. TICH growth was observed in 281 cases (70.1%). Eighty-two cases (20.4%) underwent craniectomy without TICH evacuation. In the craniectomy group, HP was observed in 71 cases (86.6%); in the noncraniectomy group (319 cases), HP occurred in 210 cases (65.8%). The difference in the incidence of HP between the two groups was statistically significant (OR 3.41, p < 0.01). The mean area of the craniectomy was 104.94 ± 27.5 cm2, and the mean CPH distance through the craniectomy was 17.85 ± 11.1 mm. The mean increase in the TICH volume was greater in the groups with a craniectomy area > 115 cm2 and CPH > 25 mm (16.12 and 14.47 cm3, respectively, p = 0.01 and 0.02). After calculating the propensity score (PS), the authors followed three statistical methods—matching, stratification, and inverse probability treatment weighting (IPTW)—thereby obtaining an adequate balance of the covariates. A statistically significant relationship was found between HP and craniectomy (OR 2.77, p = 0.004). This correlation was confirmed with the three methodologies based on the PS with odds greater than 2.
DC is a risk factor for the growth of TICH, and there is also an association between the size of the DC and the magnitude of the volume increase in the TICH.