Randy S. D’Amico

Smart wearable body sensors for patient self-assessment and monitoring

BackgroundInnovations in mobile and electronic healthcare are revolutionizing the involvement of both doctors and patients in the modern healthcare system by extending the capabilities of physiological monitoring devices. Despite significant progress within the monitoring device industry, the widespread integration of this technology into medical practice remains limited. The purpose of this review is to summarize the developments and clinical utility of smart wearable body sensors.MethodsWe reviewed the literature for connected device, sensor, trackers, telemonitoring, wireless technology and real time home tracking devices and their application for clinicians.ResultsSmart wearable sensors are effective and reliable for preventative methods in many different facets of medicine such as, cardiopulmonary, vascular, endocrine, neurological function and rehabilitation medicine. These sensors have also been shown to be accurate and useful for perioperative monitoring and rehabilitation medicine.ConclusionAlthough these devices have been shown to be accurate and have clinical utility, they continue to be underutilized in the healthcare industry. Incorporating smart wearable sensors into routine care of patients could augment physician-patient relationships, increase the autonomy and involvement of patients in regards to their healthcare and will provide for novel remote monitoring techniques which will revolutionize healthcare management and spending.

Neurosurgical oncology: advances in operative technologies and adjuncts

Abstract Modern glioma surgery has evolved around the central tenet of safely maximizing resection. Recent surgical adjuncts have focused on increasing the maximum extent of resection while minimizing risk to functional brain. Technologies such as cortical and subcortical stimulation mapping, intraoperative magnetic resonance imaging, functional neuronavigation, navigable intraoperative ultrasound, neuroendoscopy, and fluorescence-guided resection have been developed to augment the identification of tumor while preserving brain anatomy and function. However, whether these technologies offer additional long-term benefits to glioma patients remains to be determined. Here we review advances over the past decade in operative technologies that have offered the most promising benefits for glioblastoma patients.

Pre-operative intracranial meningioma embolization

Pre-operative embolization is a routinely utilized therapeutic adjunct to the resection of hypervascular lesions of the head and neck. In particular, pre-operative cerebral angiography and tumor embolization has become standard practice at many centers in the management of select intracranial meningiomas. However, controversy remains regarding its specific indications and clinical utility. In this article, we examine the principles of meningioma embolization, emphasizing the indications, risks and benefits associated with its use in the pre-operative setting.

The addition of Sunitinib to radiation delays tumor growth in a murine model of glioblastoma

Abstract Objectives: Recent preclinical studies suggest that treating glioblastoma (GBM) with a combination of targeted chemotherapy and radiotherapy may enhance the anti-tumor effects of both therapies. However, the effects of these treatments on glioma growth and progression are poorly understood. Methods: In this study, we have tested the effects of combination therapy in a mouse glioma model that utilizes a PDGF-IRES-Cre-expressing retrovirus to infect adult glial progenitors in mice carrying conditional deletions of Pten and p53. This model produces tumors with the histological features of GBM with 100% penetrance, making it a powerful system to test novel treatments. Sunitinib is an orally active, small molecule inhibitor of multiple receptor tyrosine kinases critical for tumor growth and angiogenesis, including PDGF receptors. We investigate the addition of Sunitinib to radiotherapy, and use bioluminescence imaging to characterize the effects of treatment on glioma growth and progression. Results: Treating our PDGF-driven mouse model with either Sunitinib or high-dose radiation alone delayed tumor growth and had a modest but significant effect on survival, while treating with low-dose radiation alone failed to control glioma growth and progression. The addition of Sunitinib to low-dose radiation caused a modest, but significant delay in tumor growth. However, no significant survival benefit was seen as tumors progressed in 100% of animals. Histological analysis revealed a reduction in vascular proliferation and a marked increase in brain invasion. An additional study combining Sunitinib with high-dose radiation revealed a fatal toxicity despite individual monotherapies being well tolerated. Discussion: These results show that the addition of Sunitinib to radiotherapy fails to significantly alter survival in GBM despite enhancement of the effects of radiation. Furthermore, an enhanced risk of toxicity associated with combined therapy must be considered in the design of future clinical studies.

Long-term growth and alignment after occipitocervical and atlantoaxial fusion with rigid internal fixation in young children

OBJECT The long-term consequences of atlantoaxial (AA) and occipitocervical (OC) fusion and instrumentation in young children are unknown. Anecdotal reports have raised concerns regarding altered growth and alignment of the cervical spine after surgical intervention. The purpose of this study was to determine the long-term effects of these surgeries on the growth and alignment of the maturing spine. METHODS A multiinstitutional retrospective chart review was conducted for patients less than or equal to 6 years of age who underwent OC or AA fusion with rigid instrumentation at 9 participating centers. All patients had at least 3 years of clinical and radiographic follow-up data and radiographically confirmed fusion. Preoperative, immediate postoperative, and most recent follow-up radiographs and/or CT scans were evaluated to assess changes in spinal growth and alignment. RESULTS Forty children (9 who underwent AA fusion and 31 who underwent OC fusion) were included in the study (mean follow-up duration 56 months). The mean vertical growth over the fused levels in the AA fusion patients represented 30% of the growth of the cervical spine (range 10%-50%). Three different vertical growth patterns of the fusion construct developed among the 31 OC fusion patients during the follow-up period: 1) 16 patients had substantial growth (13%-46% of the total growth of the cervical spine); 2) 9 patients had no meaningful growth; and 3) 6 patients, most of whom presented with a distracted atlantooccipital dislocation, had a decrease in the height of the fused levels (range 7-23 mm). Regarding spinal alignment, 85% (34/40) of the patients had good alignment at follow-up, with straight or mildly lordotic cervical curvatures. In 1 AA fusion patient (11%) and 5 OC fusion patients (16%), we observed new hyperlordosis (range 43°-62°). There were no cases of new kyphosis or swan-neck deformity, evidence of subaxial instability, or unintended subaxial fusion. No preoperative predictors of these growth patterns or alignment were evident. CONCLUSIONS These results demonstrate that most young children undergoing AA and OC fusion with rigid internal fixation continue to have good cervical alignment and continued growth within the fused levels during a prolonged follow-up period. However, some variability in vertical growth and alignment exists, highlighting the need to continue close long-term follow-up.

The Safety of Surgery in Elderly Patients with Primary and Recurrent Glioblastoma

BACKGROUND Glioblastoma (GBM) occurs more commonly in elderly patients. However, these patients are often excluded from clinical trials. The absence of solid evidence has resulted in a nihilistic view of GBM in the elderly and a traditionally conservative treatment approach. In particular, the safety of surgical resection for both primary and recurrent GBM is poorly understood in elderly patients. METHODS In a retrospective cohort of patients aged ≥65 years, we examined selection for biopsy, surgical resection, and reoperation for recurrent disease. We also analyzed complication rates after initial resection and reoperation for recurrent disease. We identified 319 elderly patients with pathologically proven GBM who underwent a total of 274 craniotomies at our institution between 2000 and 2012. Events were reported according to the methods used in the Glioma Outcomes Project. RESULTS The overall rate of complications after resection was 21.9%, with a rate of neurological complications of 7.7%. The rates of neurological, regional, and systemic complications were not significantly different after initial craniotomy and reoperation for GBM in elderly patients. Reoperations were not associated with an increased risk of complications. Low cardiovascular risk, improved functional status, and hemispheric GBM were associated with selection for more aggressive surgical treatment. Younger age and improved functional status were associated with a reduced likelihood of complications. CONCLUSIONS We conclude that in select patients, age alone should not preclude the decision to pursue aggressive surgical management.

Medial lenticulostriate artery aneurysm presenting with isolated intraventricular hemorrhage

Background: Isolated intraventricular hemorrhage (IVH) secondary to lenticulostriate artery aneurysm rupture is extremely rare. Thus, the diagnostic imaging modalities and therapeutic interventions utilized in the management of such cases are not clearly defined. Case Description: Here we describe a case of isolated or primary IVH (PIVH) in a 71-year-old woman presenting with severe headache. Emergent catheter cerebral angiography, performed after nondiagnostic computed tomography angiography (CTA), revealed the bleeding source to be a 4 × 2.6 mm distal medial lenticulostriate artery aneurysm that ruptured directly into the lateral ventricle. The poorly accessible location of the aneurysm for both endovascular and direct surgical treatment argued for conservative management. A good clinical outcome was obtained with rapid angiographic resolution of the ruptured aneurysm. Conclusion: Thus, lenticulostriate artery aneurysm rupture must be given diagnostic consideration in cases of isolated IVH. Emergent catheter cerebral angiography should be performed in cases such as this when noninvasive imaging is unrevealing. Conservative management may be a reasonable therapeutic option in patients with this kind of aneurysm, and spontaneous resolution can be observed.

Extent of Resection in Glioma–A Review of the Cutting Edge

Modern glioma surgery has evolved from the principal belief that safe, maximal tumor resection improves symptom management, quality of life, progression-free survival, and overall survival in both low-grade and high-grade glioma. However, in the absence of level I data, the overwhelming support for this idea is derived largely from retrospective series. As a result, the influence of increasing extent of resection and reducing tumor burden on the efficacy of postoperative chemotherapy and radiotherapy, and survival, remains inadequately defined. This situation is particularly true because gliomas represent a widely heterogeneous group of tumors with varying behaviors and prognoses rooted in their complex molecular profile. The neurosurgical community has made a large effort to define the clinical benefits of maximizing tumor resection, with particular attention paid to the ever-evolving understanding of glioma molecular heterogeneity. Important new technologies have been developed concurrently to mitigate neurologic risks related to the pursuit of maximizing extent of resection. These advances reflect the modern goal of glioma surgery to find the optimal balance between tumor removal and neurologic compromise. We review the current literature supporting safe, maximal resection for gliomas.

Severity of presentation is associated with time to recovery in spinal epidural lipomatosis

We present a patient with prednisone-induced spinal epidural lipomatosis (SEL) and relatively acute neurologic deterioration followed by rapid recovery after surgical decompression. SEL is a rare disease characterized by hypertrophy of epidural fat, most commonly associated with exogenous steroid use. To our knowledge, an analysis of the dynamics of steroid dose related to time to onset has never been performed, or of patient presentation features with respect to patient outcome. We retrospectively reviewed the literature for English language series and case reports of SEL associated with prednisone use from 1975-2013. Data were compiled for 41 patients regarding the prescribed dose of prednisone and length of treatment, as well as the severity of symptoms on the Ranawat scale, time to onset, time to recovery, and degree of recovery of neurological symptoms. Fishers exact test and analysis of variance were used for comparing proportions, and p values <0.05 were considered statistically significant. We found that the mean cumulative dose of prednisone trended towards an association with a lack of recovery (p=0.06) and may be related to rate of recovery. Prescribed prednisone dose varied inversely with the time before onset of neurological symptoms, but failed to reach statistical significance. Higher severity of presenting symptoms on the Ranawat scale were found to be associated with a higher likelihood of delayed recovery (p=0.035). Patients with symptoms lower on the Ranawat scale more frequently experienced complete neurologic recovery, though this did not reach significance. The acuity of neurological deterioration was not related to the time to recovery or ultimate degree of recovery. Severity of presentation on the Ranawat scale is associated with rate of recovery and may be related to degree of recovery in SEL patients. Cumulative dose of prednisone may be related to degree and rate of recovery. Prescribed dose of prednisone may be related to time to onset of neurological symptoms. Acuity of neurological deterioration is not related to rate or degree of recovery.

Sodium Fluorescein Facilitates Guided Sampling of Diagnostic Tumor Tissue in Nonenhancing Gliomas

BACKGROUND Accurate tissue sampling in nonenhancing (NE) gliomas is a unique surgical challenge due to their intratumoral histological heterogeneity and absence of contrast enhancement as a guide for intraoperative stereotactic guidance. Instead, T2/fluid-attenuated inversion-recovery (FLAIR) hyperintensity on MRI is commonly used as an imaging surrogate for pathological tissue, but sampling from this region can yield nondiagnostic or underdiagnostic brain tissue. Sodium fluorescein is an intraoperative fluorescent dye that has a high predictive value for tumor identification in areas of contrast enhancement and NE in glioblastomas. However, the underlying histopathological alterations in fluorescent regions of NE gliomas remain undefined. OBJECTIVE To evaluate whether fluorescein can identify diagnostic tissue and differentiate regions with higher malignant potential during surgery for NE gliomas, thus improving sampling accuracy. METHODS Thirteen patients who presented with NE, T2/FLAIR hyperintense lesions suspicious for glioma received fluorescein (10%, 3 mg/kg intravenously) during surgical resection. RESULTS Patchy fluorescence was identified within the T2/FLAIR hyperintense area in 10 of 13 (77%) patients. Samples taken from fluorescent regions were more likely to demonstrate diagnostic glioma tissue and cytologic atypia (P < .05). Fluorescein demonstrated a 95% positive predictive value for the presence of diagnostic tissue. Samples from areas of fluorescence also demonstrated greater total cell density and higher Ki-67 labeling than nonfluorescent biopsies (P < .05). CONCLUSION Fluorescence in NE gliomas is highly predictive of diagnostic tumor tissue and regions of higher cell density and proliferative activity.