Pablo F. Recinos, Shaan M. Raza, George I. Jallo, and Violette Renard Recinos
Microsurgical removal is the preferred treatment for most deep-seated, intraaxial tumors in the pediatric population. The feasibility of surgery as an option has improved with advances in surgical technology and technique. Tubular retractors disperse retraction forces over a greater surface area than do conventional retractors, which can lower the risk of ischemic complications. The authors describe their experience utilizing a new tubular retractor system specifically designed for cranial applications in conjunction with frameless neuronavigation.
The Vycor ViewSite retractor was used in 4 pediatric patients (ages 15 months and 9, 10, and 16 years) with deep-seated intraaxial tumors. The lesions included a papillary tumor of the pineal region, a low-grade astrocytoma in the occipital lobe, a dysembryoplastic neuroepithelial tumor arising from the basal ganglia, and an intraventricular low-grade glioma. The extent of white matter damage along the surgical trajectory (based on T2 or FLAIR and diffusion restriction/apparent diffusion coefficient signals) and the extent of resection were assessed on postoperative imaging.
Satisfactory resection or biopsy was achieved in all patients. A comparison of pre- and postoperative MR imaging studies revealed evidence of white matter damage along the surgical trajectory in 1 patient. None of the patients demonstrated new neurological deficits postoperatively.
Obtaining surgical access to deep-seated, intraaxial tumors is challenging. In this small series of pediatric patients, the combination of the ViewSite tubular retractor and frameless neuronavigation facilitated the surgical approach. The combination of these technologies adds to the armamentarium to safely approach tumors in deep locations.
Case report and review of the literature
Pablo F. Recinos, Chanland Roonprapunt, and George I. Jallo
✓ Brainstem epidermoid cysts are rare lesions, with only 18 reported cases in the literature and only five purely intrinsic epidermoid cysts within this group. The authors present the case of a 3-year-old girl with a history of chronic headaches, progressive diplopia, and relapsing and remitting mild right hemiparesis who was found to harbor an intrinsic brainstem epidermoid cyst at the pontomedullary junction. Initial working diagnoses included intrinsic brainstem astrocytoma and cavernoma. After tumor enlargement and progressive symptoms, a diffusion-weighted (DW) magnetic resonance (MR) imaging sequence was performed and a definitive diagnosis of an intrinsic brainstem epidermoid cyst was made in the patient. The patient underwent a suboccipital craniotomy and complete resection of the cyst with the aid of intraoperative neurophysiological monitoring. Three years after the operation, the patient is neurologically intact and no evidence of tumor recurrence has been found. The rarity of brainstem epidermoid cysts can make their diagnosis difficult; thus a DW MR imaging sequence of the brain is a useful diagnostic modality. Intrinsic brainstem epidermoid cysts can be removed safely, in a manner similar to that used for the surgical treatment of focal tumors.
Pablo F. Recinos, Jonathan A. Pindrik, Mazen I. Bedri, Edward S. Ahn, George I. Jallo, and Violette Renard Recinos
The aim of this study was to examine the feasibility and safety of ventriculoperitoneal (VP) shunt placement using a periumbilical approach for distal peritoneal access. By using this minimally invasive approach, the authors hypothesized that the cosmetic outcomes would be better than could be achieved by using a traditional minilaparotomy and that clinical results would be comparable.
A periumbilical approach was used for distal catheter insertion during a first-time VP shunt placement in 20 patients (8 males and 12 females). Median age at time of surgery was 3.0 months (range 7 days–11.9 years) and mean follow-up time was 17.8 months (range 1.2–28.0 months). The median weight of the patients was 3.99 kg (range 1.95–57.0 kg). A single incision was made along the natural crease inferior to the umbilicus. The linea alba was exposed and a 1-mm incision made while the patient was temporarily held in a Valsalva maneuver. A peritoneal trocar was then inserted through the fascial incision and the distal catheter was passed into the peritoneal space.
The incision line in all patients healed well, did not require operative revision, and was described as minimally visible by the patients' families. Mean operative time was 35 minutes. Eight patients required revision surgery. One distal failure occurred when the distal shunt tubing retracted and became coiled in the neck; this was repaired by conversion to a minilaparotomy for distal replacement. There was 1 shunt infection (5%) requiring shunt removal and replacement. One patient had significant skin thinning around the valve and proximal catheter, which required replacement of the entire shunt system, and another patient underwent a conversion to a ventriculoatrial shunt due to poor peritoneal absorption. In the remaining 4 patients who required operative revision, the peritoneal portion of the shunt was not involved.
The periumbilical approach for peritoneal access during VP shunt placement is technically feasible, has low infection rates, and has cosmetically appealing results. It may be considered as an alternative option to standard VP shunt placement techniques.
Jessica Li, Pablo F. Recinos, Brent A. Orr, Peter C. Burger, George I. Jallo, and Violette Renard Recinos
The papillary tumor of the pineal region (PTPR) is a distinct entity that is particularly rare in the pediatric population. The authors document the youngest reported patient with this clinicopathological entity to date. A case of PTPR in a 15-month-old boy is described. Initially thought to be a tectal glioma, the tumor was later identified as a pineal region tumor after demonstrating growth on routine imaging. Diagnosis of PTPR was established by histopathological evaluation of biopsy samples, which revealed papillary, cystic, and solid tumor components. The patient's postoperative course was complicated by tumor growth despite several debulking procedures and chemotherapy, as well as persistent hydrocephalus requiring 2 endoscopic third ventriculostomies and eventual ventriculoperitoneal shunt placement. After a 15-month follow-up period, the patient has received proton-beam therapy and has a stable tumor size. The PTPR is a recently described tumor of the CNS that must be included in the differential diagnosis of pineal region masses. The biological behavior, prognosis, and appropriate treatment of PTPR have yet to be fully defined.
James K. C. Liu, Varun R. Kshettry, Pablo F. Recinos, Kambiz Kamian, Richard P. Schlenk, and Edward C. Benzel
Surgical education has been forced to evolve from the principles of its initial inception, in part due to external pressures brought about through changes in modern health care. Despite these pressures that can limit the surgical training experience, training programs are being held to higher standards of education to demonstrate and document trainee competency through core competencies and milestones. One of the methods used to augment the surgical training experience and to demonstrate trainee proficiency in technical skills is through a surgical skills laboratory. The authors have established a surgical skills laboratory by acquiring equipment and funding from nondepartmental resources, through institutional and private educational grants, along with product donations from industry. A separate educational curriculum for junior- and senior-level residents was devised and incorporated into the neurosurgical residency curriculum. The initial dissection curriculum focused on cranial approaches, with spine and peripheral nerve approaches added in subsequent years. The dissections were scheduled to maximize the use of cadaveric specimens, experimenting with techniques to best preserve the tissue for repeated uses. A survey of residents who participated in at least 1 year of the curriculum indicated that participation in the surgical skills laboratory translated into improved understanding of anatomical relationships and the development of technical skills that can be applied in the operating room. In addition to supplementing the technical training of surgical residents, a surgical skills laboratory with a dissection curriculum may be able to help provide uniformity of education across different neurosurgical training programs, as well as provide a tool to assess the progression of skills in surgical trainees.
Mari L. Groves, Patricia L. Zadnik, Pablo F. Recinos, Violette Renard, and George I. Jallo
The authors present a case of a 27-year-old patient who presented with spastic gait and worsening difficulty walking over a 6 month period. Spinal MR imaging revealed a heterogeneously enhancing intramedullary spinal cord tumor (IMSCT) with associated syrinx in the cervical spine. The lesion was resected through posterior en bloc laminotomy, durotomy, and microscopic resection of the intramedullary component followed by laminoplasty reconstruction. Surgical resections with a goal of gross total resection can significantly improve overall survival and progression free survival in patients with low-grade IMSCT. The procedure is presented in an edited, high-definition format with accompanying narrative.
The video can be found here: http://youtu.be/Ui9bn82PtP8.
Juan C. Fernandez-Miranda, James J. Evans, Paul A. Gardner, Carl H. Snyderman, and Pablo F. Recinos
Joao Paulo Almeida, Zachary Cappello, Hamid Borghei-Razavi, Pablo F. Recinos, Raj Sindwani, and Varun R. Kshettry
Petroclival chondrosarcomas are a formidable surgical challenge given the close relationship to critical neurovascular structures. The endoscopic endonasal approach can be utilized for many petroclival chondrosarcomas. However, tumors that extend to the inferior petrous apex require working behind the internal carotid artery (ICA). We present a case of a 33-year-old with a 1-year history of complete abducens palsy, with imaging showing an enhancing mass centered at the left petroclival fissure and inferior petrous apex behind the paraclival carotid artery and extending down into the nasopharynx abutting the cervical ICA. In this video, we describe the surgical steps of the endoscopic endonasal translacerum approach with ICA skeletonization and mobilization. We also highlight the relevant surgical anatomy with anatomical dissections to supplement the surgical video. The patient did well without complications. Postoperative MRI demonstrated complete resection and pathology revealed grade II chondrosarcoma. He underwent adjuvant proton beam radiotherapy.
The video can be found here: https://youtu.be/80QXALJW9ME.
Danielle F. Eytan, Varun R. Kshettry, Raj Sindwani, Troy D. Woodard, and Pablo F. Recinos
Endoscopic endonasal treatment of petrous apex cholesterol granulomas allows for a natural drainage pathway into the nasopharynx. Because of the limited number of case series in the literature, there is limited evidence of recurrence rates and outcomes following endoscopic endonasal management. The purpose of this study was to determine the surgical outcomes of endoscopic endonasal approaches in the treatment of cholesterol granulomas of the petrous apex.
A systematic literature review was performed using PubMed for articles published from January 1980 to April 2014 to identify all studies reporting outcomes for endoscopic endonasal surgical management of cholesterol granulomas of the petrous apex. Operative approach, use of a stent, symptom outcome, restenosis, cyst recurrence, reoperation, and complications were extracted from included studies.
A total of 53 patient cases were included from 22 relevant studies. The mean age was 41 years, and 26 patients (49%) were female. Stents were used in 45.1% of cases. Symptom resolution or improvement was seen in 98.6% of cases at follow-up (mean follow-up 20 months). Complications were reported in 13.2% of cases, with the most common complication being epistaxis. Restenosis on follow-up office endoscopic examination occurred in 9 of 45 cases (20.0%). Only 4 of these restenosis cases resulted in symptomatic cyst recurrence, resulting in an overall recurrence rate of 7.5%. The mean time from surgery to cyst recurrence was 13.5 months. The rate of symptomatic cyst recurrence was 10.7% in cases without the use of a stent compared with 4.3% in cases with stent placement (p = 0.6).
Based on current literature, endoscopic endonasal approaches result in a high rate of symptom improvement or resolution. Complication rates are lower than prior case series that have utilized open approaches. Asymptomatic restenosis can be managed conservatively, since it is associated with symptomatic cyst recurrence less than half of the time. This study revealed a nonsignificant trend toward a decrease in symptomatic cyst recurrence when a stent was used, but further work is needed to clarify its impact.