RESUMO
Patients with cochlear implants (CIs) commonly undergo neurosurgical interventions for concurrent pathologies. The neurosurgeon must be aware of the limitations these devices place on treating these patients and all pertinent interactions CIs have with common neurosurgical instruments and procedures. A literature search was performed utilizing the terms "cochlear implant" and "neurosurgery" or "neurosurgical" and all associated iterations. We reviewed the abstracts of 146 generated reports and eight published papers discussing the interaction and limitations of CI use in different neurosurgical procedures. Five realms were identified in which a CI may potentially interfere with standard neurosurgical care: Magnetic resonance imaging (MRI), radiotherapy, deep brain stimulation (DBS), intraventricular shunt placement, and intraoperative neuromonitoring (IONM). First, MRI use with CIs is limited due to thermal injury risk, imaging disruption, and implant damage. Secondly, high-dose >50 Gy single-fraction linear accelerator-based radiosurgery has been demonstrated to result in a loss of radio frequency link range in CIs, interfering with their function. Next, during surgery for DBS, the need for MRI and microelectrode recording requires CI magnet removal by neurotology and the surgeon must communicate with a non-hearing patient. Tunneling of shunts must accommodate CI position retroauricularly, if ipsilateral, and programmable valves must be placed >2 cm from the CI to prevent interference. Intraoperative neuromonitoring may produce voltages that interfere with CIs, and while monopolar cautery may pose the same risk, no study has proven this to date. Generally, bipolar cautery is safe and favored >1 cm from CIs. MRI use is limited in CI patients, although MRI-safer devices are in production. DBS electrodes may be successfully placed after CI magnet removal. Programmable shunt valves may be placed >2 cm away from CIs and radiosurgery <50 Gy has not demonstrated harm to these devices. IONM and monopolar cautery have not been demonstrated to directly affect CIs; however, more research is needed.
RESUMO
Intervertebral cage mispositioning is an uncommon complication of a posterior lumbar corpectomy. Most frequently, cages are placed obliquely, laterally, or protruding. However, there are few reports of implanted cages that fail to contact the adjacent vertebral endplate and thus no descriptions of successful revisions. The objective of this case report is to report a unique case of minimally invasive rescue vertebroplasty with cement augmentation following a lumbar corpectomy that resulted in graft-endplate noncontact in a medically complicated patient A 60-year-old male with a history of active intravenous (IV) drug use, untreated hepatitis C virus (HCV) infection, and chronic malnourishment presented with low back pain. He had a history of vertebral osteomyelitis managed with intravenous antibiotics, although he was noncompliant with infusions. The diagnosis of L2-L3 discitis-osteomyelitis with intradiscal abscess causing cord compression was made using inpatient lumbar imaging. The initial intervention was accomplished with L2 and L3 vertebral corpectomy with decompression and expandable cage placement as well as a T10-pelvis posterior fixation. Despite the resolution of presenting symptoms, routine postoperative radiographs identified noncontact between the inferior surface of the cage and the superior endplate of the L4 vertebral body. Salvage therapy was pursued via fluoroscopy-guided vertebroplasty with cement augmentation to correct cage malposition. Secondary surgical intervention was successful in bringing the intervertebral cage into contact with the adjacent vertebral body. Lower extremity strength improved, and back pain was resolved. The postoperative motor examination remained unchanged after the rescue procedure. Accurate intraoperative cage placement can be difficult in patients with poor bone quality, especially in the setting of ongoing infection and cachexia. For this reason, routine postoperative imaging is crucial to assessing graft complications. In patients who are poor candidates for revision surgery, we demonstrate that an interventional radiology-based approach may be successful in correcting cage mispositioning and preventing further changes during healing and fusion.
RESUMO
Background: Antigametocyte-specific immune responses may regulate Plasmodium falciparum gametocyte density, providing the rationale for pursuing transmission-blocking vaccines (TBVs) that target gametocytes in the human host. Methods: To identify novel antigametocyte TBV antigens, we interrogated the gametocyte proteome with our whole proteome differential screening method using plasma from a treatment-reinfection study conducted in western Kenya. At the start of the high-transmission season, 144 males (12-35 years) were enrolled and treated with quinine and doxycycline, peripheral venous blood samples were obtained, volunteers were observed, and weekly blood films were obtained for 18 weeks to quantify gametocytemia. Using plasma pooled from individuals with low versus high gametocyte carriage, we differentially screened a P falciparum gametocyte stage complementary deoxyribonucleic acid expression library. Results: We identified 8 parasite genes uniquely recognized by gametocyte-resistant but not by gametocyte-susceptible individuals. Antibodies to one of these antigens, PfsEGXP, predicted lower gametocytemia measured over the 18-week transmission season (P = .021). When analyzed dichotomously, anti-PfsEGXP responders had 31% lower gametocyte density over 18 weeks of follow-up, compared with nonresponders (P = .04). Conclusions: PfsEGXP is one of the first reported gametocyte-specific target of antibodies that predict decreased gametocyte density in humans and supports our novel TBV antigen discovery platform.
