Lifetime Cost and Quality-Adjusted Life-Years Across Management Options for Small- and Medium-Sized Sporadic Vestibular Schwannoma

OBJECTIVE

Despite the growing emphasis on healthcare costs, limited data address this aspect of care within the vestibular schwannoma (VS) literature. We sought to determine which strategy confers the lowest lifetime cost and greatest quality-adjusted life-years (QALYs) for patients with small- to medium-sized sporadic VS tumors.

STUDY DESIGN

A Markov model was created to determine the most cost-effective management algorithm. Tumor characteristics, magnetic resonance imaging surveillance schedule, treatment outcomes, and health-related quality of life values were derived from previously published data. Cost estimates were based on CMS Fee Schedule reimbursement rates.

SETTING

Economic Evaluation Service within the Kern Center for the Science of Healthcare Delivery.

PATIENTS

Patients diagnosed with small- to medium-sized sporadic VS.

INTERVENTIONS

Upfront microsurgery following diagnosis, upfront radiosurgery following diagnosis, observation with microsurgery reserved for observed tumor growth, and observation with radiosurgery reserved for observed tumor growth.

RESULTS

Across patient ages at time of diagnosis ranging from 18 to 70 years, observation with subsequent radiosurgery used for tumor growth was the most cost-effective management algorithm while upfront microsurgery was the least. When presented with a hypothetical 50-year-old patient, the strategy with the lowest lifetime cost and highest QALYs was observation with subsequent radiosurgery reserved for tumor growth ($32,161, 14.11 QALY), followed by observation with microsurgery reserved for tumor growth ($34,503, 13.94 QALY), upfront radiosurgery ($43,456, 14.02 QALY), and lastly, upfront microsurgery ($47,252, 13.60 QALY). Sensitivity analyses varying mortality rates, estimated costs, health-related quality of life, and progression to nonserviceable hearing demonstrated consistent ranking among treatments.

CONCLUSIONS

When considering initial management of small- and medium-sized sporadic VSs, neither lifetime cost nor QALYs support upfront microsurgery or radiosurgery, even for younger patients. Initial observation with serial imaging, reserving radiosurgery or microsurgery for patients exhibiting tumor growth, confers the greatest potential for optimized lifetime healthcare cost and QALY outcomes.

Bacterial Brain Abscess: An Outline for Diagnosis and Management

Despite advances in the diagnosis and management of brain abscess, significant associated morbidity and mortality remain high. We retrospectively reviewed adults who presented with pyogenic brain abscess from January 1, 2009, through June 30, 2020. Overall, 247 patients were identified. The median age was 59 years, and 33.6% had a history of head and neck surgery or traumatic brain injury. Diagnostic brain magnetic resonance imaging (MRI) was performed in the bulk (93.1%) of patients. A total of 205 patients (83%) were managed with medical and surgical treatment. The most common definitive antibiotic regimen was monotherapy (48.2%). The median duration of antimicrobial therapy was 42 days. Compared with those who received combined therapy, patients with medical therapy alone had a higher mortality rate (21.4% vs 6%; P =. 003) with more neurologic sequelae (31% vs 27.1%; P = .5). Most patients with brain abscesses are older with multiple underlying comorbidities, and one-third had antecedent head and neck surgery. A prompt combined surgical and medical approach with prolonged antimicrobial therapy may cure the infection with avoidance of permanent residual neurologic deficits.

Anterior nucleus of the thalamus seizure detection in ambulatory humans

There is a paucity of data to guide anterior nucleus of the thalamus (ANT) deep brain stimulation (DBS) with brain sensing. The clinical Medtronic Percept DBS device provides constrained brain sensing power within a frequency band (power-in-band [PIB]), recorded in 10-min averaged increments. Here, four patients with temporal lobe epilepsy were implanted with an investigational device providing full bandwidth chronic intracranial electroencephalogram (cEEG) from bilateral ANT and hippocampus (Hc). ANT PIB-based seizure detection was assessed. Detection parameters were cEEG PIB center frequency, bandwidth, and epoch duration. Performance was evaluated against epileptologist-confirmed Hc seizures, and assessed by area under the precision-recall curve (PR-AUC). Data included 99 days of cEEG, and 20, 278, 3, and 18 Hc seizures for Subjects 1-4. The best detector had 7-Hz center frequency, 5-Hz band width, and 10-s epoch duration (group PR-AUC = .90), with 75% sensitivity and .38 false alarms per day for Subject 1, and 100% and .0 for Subjects 3 and 4. Hc seizures in Subject 2 did not propagate to ANT. The relative change of ANT PIB was maximal ipsilateral to seizure onset for all detected seizures. Chronic ANT and Hc recordings provide direct guidance for ANT DBS with brain sensing.

Outcomes following surgical management of vagus nerve stimulator-related infection: a retrospective multi-institutional study

OBJECTIVE

Surgical site infection (SSI) is a rare but significant complication after vagus nerve stimulator (VNS) placement. Treatment options range from antibiotic therapy alone to hardware removal. The optimal therapeutic strategy remains open to debate. Therefore, the authors conducted this retrospective multicenter analysis to provide insight into the optimal management of VNS-related SSI (VNS-SSI).

METHODS

Under institutional review board approval and utilizing an institutional database with 641 patients who had undergone 808 VNS-related placement surgeries and 31 patients who had undergone VNS-related hardware removal surgeries, the authors retrospectively analyzed VNS-SSI.

RESULTS

Sixteen cases of VNS-SSI were identified; 12 of them had undergone the original VNS placement procedure at the authors' institutions. Thus, the incidence of VNS-SSI was calculated as 1.5%. The mean (± standard deviation) time from the most recent VNS-related surgeries to infection was 42 (± 27) days. Methicillin-sensitive staphylococcus was the usual causative bacteria (58%). Initial treatments included antibiotics with or without nonsurgical procedures (n = 6), nonremoval open surgeries for irrigation (n = 3), generator removal (n = 3), and total or near-total removal of hardware (n = 4). Although 2 patients were successfully treated with antibiotics alone or combined with generator removal, removal of both the generator and leads was eventually required in 14 patients. Mild swallowing difficulties and hoarseness occurred in 2 patients with eventual resolution.

CONCLUSIONS

Removal of the VNS including electrode leads combined with antibiotic administration is the definitive treatment but has a risk of causing dysphagia. If the surgeon finds dense scarring around the vagus nerve, the prudent approach is to snip the electrode close to the nerve as opposed to attempting to unwind the lead completely.

Intraoperative lateral rectus electromyographic recordings optimized by deep intraorbital needle electrodes

OBJECTIVE

We demonstrate the advantages and safety of long, intraorbitally-placed needle electrodes, compared to standard-length subdermal electrodes, when recording lateral rectus electromyography (EMG) during intracranial surgeries.

METHODS

Insulated 25 mm and uninsulated 13 mm needle electrodes, aimed at the lateral rectus muscle, were placed in parallel during 10 intracranial surgeries, examining spontaneous and stimulation-induced EMG activities. Postoperative complications in these patients were reviewed, alongside additional patients who underwent long electrode placement in the lateral rectus.

RESULTS

In 40 stimulation-induced recordings from 10 patients, the 25 mm electrodes recorded 6- to 26-fold greater amplitude EMG waveforms than the 13 mm electrodes. The 13 mm electrodes detected greater unwanted volume conduction upon facial nerve stimulation, typically exceeding the amplitude of abducens nerve stimulation. Except for one case with lateral canthus ecchymosis, no clinical or radiographic complications occurred in 36 patients (41 lateral rectus muscles) following needle placement.

CONCLUSIONS

Intramuscular recordings from long electrode in the lateral rectus offers more reliable EMG monitoring than 13 mm needles, with excellent discrimination between abducens and facial nerve stimulations, and without significant complications from needle placement.

SIGNIFICANCE

Long intramuscular electrode within the orbit for lateral rectus EMG recording is practical and reliable for abducens nerve monitoring.

Insular epilepsy surgery: lessons learned from institutional review and patient-level meta-analysis

OBJECTIVE

Insular lobe epilepsy is a challenging condition to diagnose and treat. Due to anatomical intricacy and proximity to eloquent brain regions, resection of epileptic foci in that region can be associated with significant postoperative morbidity. The aim of this study was to review available evidence on postoperative outcomes following insular epilepsy surgery.

METHODS

A comprehensive literature search (PubMed/MEDLINE, Scopus, Cochrane) was conducted for studies investigating the postoperative outcomes for seizures originating in the insula. Seizure freedom at last follow-up (at least 12 months) comprised the primary endpoint. The authors also present their institutional experience with 8 patients (4 pediatric, 4 adult).

RESULTS

A total of 19 studies with 204 cases (90 pediatric, 114 adult) were identified. The median age at surgery was 23 years, and 48% were males. The median epilepsy duration was 8 years, and 17% of patients had undergone prior epilepsy surgery. Epilepsy was lesional in 67%. The most common approach was transsylvian (60%). The most commonly resected area was the anterior insular region (n = 42, 21%), whereas radical insulectomy was performed in 13% of cases (n = 27). The most common pathology was cortical dysplasia (n = 68, 51%), followed by low-grade neoplasm (n = 16, 12%). In the literature, seizure freedom was noted in 60% of pediatric and 69% of adult patients at a median follow-up of 29 months (75% and 50%, respectively, in the current series). A neurological deficit occurred in 43% of cases (10% permanent), with extremity paresis comprising the most common deficit (n = 35, 21%), followed by facial paresis (n = 32, 19%). Language deficits were more common in left-sided approaches (24% vs 2%, p < 0.001). Univariate analysis for seizure freedom revealed a significantly higher proportion of patients with lesional epilepsy among those with at least 12 months of follow-up (77% vs 59%, p = 0.032).

CONCLUSIONS

These findings may serve as a benchmark when tailoring decision-making for insular epilepsy, and may assist surgeons in their preoperative discussions with patients. Although seizure freedom rates are quite high with insular epilepsy treatment, the associated morbidity needs to be weighed against the potential for seizure freedom.

Pituitary Tumor Surgery: Comparison of Endoscopic and Microscopic Techniques at a Single Center

OBJECTIVE

To understand the transition from microscopic surgery (MS) to endoscopic surgery (ES) on the pituitary across the United States, we assessed a single institution practicing both procedures to discern advantages and disadvantages for each.

PATIENTS AND METHODS

Retrospective institutional chart review of 534 patients in a large practice over a 6-year period (January 1, 2014, to December 31, 2019) comparing a single MS neurosurgeon with a single ES neurosurgeon operating on the same days.

RESULTS

In this series, 14% (n=75) of patients had a prior operation, there were no carotid artery injuries, the overall risk for a postoperative infection was 0.4% (n=2), and risk for a postoperative cerebrospinal fluid leak requiring treatment was 2.0% (n=11). Mean ± SD hospital stay was 1.3±0.04 days; readmission for any reason within 30 days occurred in 3.4% (n=18) of patients. The mean volumetric resection for MS was 86.9%±1.7% and for ES was 91.7%±1.3% (P=.03). There was a higher rate of notable events (P=.015) with MS, but MS had 16% lower cost and operative times were 48 minutes shorter than for ES (83±7 vs 131±6 minutes). The ES required substantially fewer postoperative secondary treatments such as radiation therapy (P=.003).

CONCLUSION

Pituitary surgery is a very safe and effective procedure regardless of technique. The MS has shorter operative times and overall lower cost. The ES results in increased volumetric resection and fewer secondary treatments. Both techniques can be valuable to a large practice, and understanding these niches is important when selecting optimal approaches to pituitary surgery for a given patient.

Anterior Nucleus of the Thalamus Deep Brain Stimulation with Concomitant Vagus Nerve Stimulation for Drug-Resistant Epilepsy

BACKGROUND

The Food and Drug Administration approved the deep brain stimulation of the anterior nucleus of the thalamus (ANT-DBS) as an adjunctive therapy for drug-resistant epilepsy (DRE) in the United States in 2018. The DBS Therapy for Epilepsy Post-Approval Study is further evaluating the safety and effectiveness of ANT-DBS among different patients' groups. For this study, devices for vagus nerve stimulation (VNS) must be removed prior to enrolment.

OBJECTIVE

To investigate the outcomes of concomitant ANT-DBS and VNS treatment for DRE.

METHODS

A retrospective analysis was performed for 33 patients who underwent ANT-DBS using previous VNS to define distinct subgroups: standard ANT-DBS (9 subjects), ANT-DBS with functional VNS (12 subjects), and ANT-DBS with the VNS implantable pulse generator explanted or turned off at the time of the DBS (12 subjects). Effectiveness and safety data were analyzed across the whole population and among subgroups.

RESULTS

A mean decrease in seizure frequency of 55% was observed after a mean follow-up of 25.5 mo. Approximately 67% of patients experienced ≥50% reduction in seizure frequency. Seizure reduction percentage was not significantly different among groups. Approximately 50% of subjects with no appreciable improvement and 75% of those who showed benefit after VNS (including improvement in seizure frequency, seizure severity, and seizure duration or quality of life) achieved a seizure reduction ≥50% after ANT-DBS surgery. There were no complications related to concomitant VNS and ANT-DBS.

CONCLUSION

ANT-DBS for DRE provides excellent results despite previous and ongoing VNS therapy. Removal of VNS does not appear to be necessary before ANT-DBS.

Sinonasal Osteosarcoma: Report of 14 New Cases and Systematic Review of the Literature

Objective  The objective of this study is to describe the clinical presentation, tumor characteristics, natural history, and treatment patterns of sinonasal osteosarcoma. Methods  Fourteen patients who had been treated for osteosarcoma of the nasal cavity and paranasal sinuses at a tertiary care center were reviewed. In addition, a systematic review of the literature for osteosarcoma of the sinonasal cavity was performed. Results  In a systematic review, including 14 patients from the authors' institution, 53 total studies including 88 patients were assessed. Median follow-up was 18 months (interquartile range: 8-39 months). The most common presenting symptoms were facial mass or swelling (34%), and nasal obstruction (30%). The most common paranasal sinus involved by tumor was the maxillary sinus (64%), followed by the ethmoid sinuses (52%). The orbit (33%), dura (13%) and infratemporal fossa (10%) were the most common sites of local invasion. The majority of patients underwent surgery followed by adjuvant therapy (52.4%). Increasing age was associated with decreased overall survival rate (unit risk ratio [95% confidence interval (CI)] = 1.02 [1.003-1.043]; p  = 0.0216) and T4 disease was associated with decreased disease-specific survival rate (hazard ratio [HR] = 2.87; p  = 0.0495). The 2- and 5-year overall survival rates were 68 and 40%, respectively, while 2- and 5-year disease-specific survival rates were 71% and 44%, respectively. Conclusion  Sinonasal osteosarcomas are uncommon tumors and can pose a significant therapeutic challenge. Increasing age and T4 disease are associated with worse prognosis. This disease usually warrants consultation by a multidisciplinary team and consideration of multimodality therapy.

Cochlear implantation after radiosurgery for vestibular schwannoma

OBJECTIVE

The object of this study was to ascertain outcomes of cochlear implantation (CI) following stereotactic radiosurgery (SRS) for vestibular schwannoma (VS).

METHODS

The authors conducted a retrospective chart review of adult patients with VS treated with SRS who underwent CI between 1990 and 2019 at a single tertiary care referral center. Patient demographics, tumor features, treatment parameters, and pre- and postimplantation audiometric and clinical outcomes are presented.

RESULTS

Seventeen patients (18 ears) underwent SRS and ipsilateral CI during the study period. Thirteen patients (76%) had neurofibromatosis type 2 (NF2). Median age at SRS and CI were 44 and 48 years, respectively. Median time from SRS to CI was 60 days, but notably, 4 patients underwent SRS and CI within 1 day and 5 patients underwent CI more than 7 years after SRS. Median marginal dose was 13 Gy. Median treatment volume at the time of SRS was 1400 mm3 (range 84-6080 mm3, n = 15 patients). Median post-CI PTA was 28 dB HL, improved from 101 dB HL preoperatively (p < 0.001). Overall, 11 patients (12 ears) exhibited open-set speech understanding. Sentence testing was performed at a median of 10 months (range 1-143 months) post-CI. The median AzBio sentence score for patients with open-set speech understanding was 76% (range 19%-95%, n = 10 ears). Two ears exhibited Hearing in Noise Test (HINT) sentence scores of 49% and 95%, respectively. Four patients achieved environmental sound awareness without open-set speech recognition. Two had no detectable auditory percepts.

CONCLUSIONS

Most patients who underwent CI following SRS for VS enjoyed access to sound at near-normal levels, with the majority achieving good open-set speech understanding. Implantation can be performed immediately following SRS or in a delayed fashion, depending on hearing status as well as other factors. This strategy may be applied to cases of sporadic or NF2-associated VS.

ABBREVIATIONS

AAO-HNS = American Academy of Otolaryngology-Head and Neck Surgery; ABI = auditory brainstem implant; CI = cochlear implantation; CN = cranial nerve; CNC = consonant-nucleus-consonant; CPA = cerebellopontine angle; EPS = electrical promontory stimulation; ESA = environmental sound awareness; HINT = Hearing in Noise Test; IAC = internal auditory canal; NF2 = neurofibromatosis type 2; OSP = open-set speech perception; PTA = pure tone average; SRS = stereotactic radiosurgery; VS = vestibular schwannoma; WRS = word recognition score.

Combined Anterior Transmaxillary (Caldwell-Luc) With an Endoscopic Endonasal Transpterygoid Approach for Resection of a Large Juvenile Nasopharyngeal Angiofibroma: 2-Dimensional Operative Video

Juvenile nasopharyngeal angiofibroma (JNA) is a highly vascular benign tumor that originates in the sphenopalatine foramen and often spreads to adjacent compartments.1 Microsurgical resection with preoperative embolization remains the treatment of choice.2 We present a case of a large JNA involving multiple compartments. The patient is a 20-yr-old male who presented with long-term right nasal congestion. The MRI demonstrated a large enhancing mass that extended from the right nasal cavity and nasopharynx into the right pterygopalatine fossa (PPF), infratemporal fossa (ITF), and parapharyngeal space. Preoperative angiogram for embolization showed a highly vascular tumor with blood supply mainly from the internal maxillary artery and about 10% from a persistent mandibular branch of the internal carotid artery. Based on the UPMC JNA staging system, this tumor was a stage IV.2 A combined anterior transmaxillary (Caldwell-Luc) with an endoscopic endonasal transpterygoid approach was performed. The addition of the anterior transmaxillary approach increases the surgical freedom for traditional bipolar devices and improves the view and trajectory to more lateral structures like the PPF and ITF.3 Gross total resection was achieved without complications. The patient was discharged home with a partial V2 numbness (right superior gum) that improved with time. The endoscopic endonasal approach is a safe and effective technique even for large JNA. A multidisciplinary team consisting of an interventional radiologist, a skull base neurosurgeon, and an otorhinolaryngologist with expertise in endoscopic surgery may play a role for optimal surgical results. The patient consented for the procedure and for the video production.

Use of Sundt Clip Graft for the Treatment of Intracranial Aneurysms: 2-Dimensional Operative Video

Dr Thoralf Sundt III joined the department of neurosurgery at Mayo Clinic in 1969 and served as chairman from 1980 until his death in 1992. Dr Sundt was a pioneer in the field of cerebrovascular neurosurgery and among his many contributions to neurosurgical technology was the introduction of the Sundt clip graft (Codman, Raynham, Massachusetts), which was developed in partnership with Dr George Kees. This device is a vessel-encircling Teflon or Dacron graft loaded on a circular metallic spring initially designed to repair injuries to vessel walls during intracranial aneurysm surgery,1 which was not an uncommon complication resulting from the use of contemporary aneurysm clips.2 When used for this purpose, the clip graft has demonstrated both safety and efficacy in a modern series of surgical treatment of intracranial aneurysm.3 An additional application of the clip graft is the direct clipping of aneurysms, particularly side-wall aneurysms, though Dr Sundt recognized that the potential to occlude perforating arteries adjacent to the aneurysm neck would limit the general use of the clip graft for aneurysm clipping.2 In the following video, we present archival footage of Dr Sundt utilizing the Sundt clip graft during intracranial aneurysm surgery. The 3 cases are of the treatment of posterior communicating, middle cerebral, and anterior communicating artery aneurysms and depict the potential applications of the clip graft during aneurysm surgery. We also present footage of animal experiments Dr Sundt performed to validate the use of the clip graft. This footage likely represents some of the first microscopic neurosurgical recordings ever made. The patients consented to the procedure and to presentation of video recordings at the time of initial surgery. Image of Sundt at 0:11, Reproduced with permission from the American Association of Neurological Surgeons, 5550 Meadowbrook Dr, Rolling Meadows, IL 60008. Figures at 2:26 and 2:28, from Park PJ, Meyer FB, The Sundt clip graft, Neurosurgery, 2010;66(6 suppl operative):300-305, by permission of the Congress of Neurological Surgeons. Figure at 2:35, ©2009 Mayo, Clingman. Used with permission.

Does pituitary compression/empty sella syndrome contribute to MRI-negative Cushing's disease? A single-institution experience

OBJECTIVE

Cushing's disease arises from functioning adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas. These tumors can be very small and evade detection by MRI. Empty sella syndrome is a phenomenon by which an arachnoid outpouching of CSF into the sella leads to compression of the pituitary, likely due to intracranial hypertension (a common issue in Cushing's disease), further leading to difficulty in visualizing the pituitary gland that may contribute to difficulty in finding a tumor on MRI, so-called MRI-negative Cushing's disease. The authors sought to examine the association between empty sella syndrome and MRI-negative Cushing's disease.

METHODS

A single-institution database of Cushing's disease cases from 2000 to 2017 was reviewed, and 197 cases were included in the analysis. One hundred eighty patients had a tissue diagnosis of Cushing's disease and 17 had remission with surgery, but no definitive tissue diagnosis was obtained. Macroadenomas (tumors > 1 cm) were excluded. The degree of empty sella syndrome was graded on the degree of CSF visualized in the sella on midline sagittal T1-weighted MRI.

RESULTS

Of the 197 cases identified, 40 (20%) presented with MRI-negative disease, and empty sella syndrome was present in 49 cases (25%). MRI-negative disease was found in 18 (37%) of 49 empty sella cases versus 22 (15%) of 148 cases without empty sella syndrome present. Empty sella syndrome was significantly associated with MRI-negative disease (OR 3.32, 95% CI 1.61-6.74, p = 0.0018). Decreased thickness of the pituitary gland was also associated with MRI-negative disease (mean thickness 5.6 vs 6.8 mm, p = 0.0002).

CONCLUSIONS

Empty sella syndrome is associated with an increased rate of MRI-negative Cushing's disease. Pituitary compression causing a relative reduction in the volume of the pituitary for imaging is a plausible cause for not detecting the tumor mass with MRI.

Sinonasal adenocarcinoma: Population-based analysis of demographic and socioeconomic disparities

BACKGROUND

Sinonasal adenocarcinoma (SNAC) is a rare tumor. The impact of health disparities on survival, stage at presentation, and utilization of surgery is not well understood in patients with SNAC.

METHODS

The Surveillance, Epidemiology, and End Results database was queried for cases of SNAC from 1973 to 2015. Cases were analyzed to assess for disparities in presentation, treatment, and survival.

RESULTS

SNAC was identified in 630 patients. In a multivariate model of overall survival, an age increase of 10 years (Hazard Ratio (HR) = 1.37, p < 0.001), male sex (HR = 1.26, p = 0.045), and more recent decade of diagnosis (HR = 0.74, p < 0.001) were significantly related to time-to-death. There is a higher rate of SNAC-related death in counties with more rural populations (p = 0.027).

CONCLUSION

Future interventions targeting rural and less well-educated populations may improve care with the goal of increasing the span of healthy life and reducing survival disparities related to SNAC.

Acute Sialadenitis After Skull Base Surgery: Systematic Review and Summative Practice Recommendations

BACKGROUND

Sialadenitis is a rare complication of skull base neurosurgery, in which the submandibular gland undergoes acute inflammation with edema after surgery. Although attributable to transient obstruction or manual compression, presentation may be rapidly life-threatening as a result of airway obstruction. Understanding risk factors is limited at present, and no practical management guidelines have been reported. Our objective was to survey the literature and to characterize the associated risk factors, treatment considerations, and overall trends in outcomes for patients experiencing post skull base neurosurgery sialadenitis.

METHODS

A search of the Ovid EMBASE, SCOPUS, and PubMed databases from inception through August 2020 was performed via Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Systematic review identified 13 publications describing 18 cases of acute sialadenitis after skull base surgery. We describe the 19th reported case. Commonalities include the need for aggressive respiratory support as intubation or emergent tracheostomy is almost universally required. Risk factors are poorly understood but may include extreme flexion and/or rotation of the head and neck. Outcomes are favorable overall, although secondary complications have been described.

CONCLUSIONS

Sialadenitis is a rare but potentially life-threatening complication of skull base neurosurgery, owing to acute loss of airway and the potential for a diverse array of secondary complications.

Preoperative embolization of jugular paraganglioma tumors using particles is safe and effective

BACKGROUND

Jugular paragangliomas represent a surgical challenge due to their vascularity and proximity to vital neurovascular structures. Preoperative embolization aids in reducing intraoperative blood loss, transfusion requirements, and improves surgical visualization. Several embolization agents have been used.

OBJECTIVE

The aim of this study is to evaluate the safety and efficacy of PVA in pre-operative embolization of jugular paragangliomas.

METHODS

A retrospective review of all patients who underwent jugular paraganglioma resection with pre-operative embolization between 2000 and 2020 was performed. Pre-operative data including baseline patient and tumor characteristics were documented. Outcomes of preoperative embolization including extent of devascularization and post-embolization complications were recorded. Early and long-term postoperative outcomes were reported.

RESULTS

Twenty-nine patients met study criteria with a median age of 38 years. Average tumor size was 3.4±1.8 cm. The most commonly encountered arterial feeder was the ascending pharyngeal artery followed by the posterior auricular artery. More than 50% reduction in tumor blush was achieved in 25 patients (86.2%). None of the patients experienced new or worsening cranial neuropathy following embolization. Gross total or Near total resection was achieved in 13 patients (44.8%). A STR or NTR was chosen in these patients to preserve cranial nerve function or large vessel integrity. Average intraoperative estimated blood loss was 888 ml, 9 patients (31%) required intra-operative transfusion of blood products. Extent of resection and post-operative complications did not correlate with extent of devascularization.

CONCLUSION

Pre-operative embolization of jugular paraganglioma tumors with PVA particles is an effective strategy with a high safety profile.

Long-term outcomes of grade I/II skull base chondrosarcoma: an insight into the role of surgery and upfront radiotherapy

PURPOSE

To clarify the need for post-operative radiation treatment in skull base chondrosarcomas (SBCs).

METHODS

A retrospective analysis of patients with grade I or II SBC. Patients were divided according to post-surgical treatment strategies: (A) planned upfront radiotherapy and (B) watchful waiting. Tumor control and survival were compared between the treatment groups. The median follow-up after resection was 105 months (range, 9-376).

RESULTS

Thirty-two patients (Grade 1, n = 16; Grade 2, n = 16) were included. The most frequent location was petroclival (21, 64%). A gross total resection (GTR) was achieved in 11 patients (34%). Fourteen (44%) underwent upfront radiotherapy (group A) whereas 18 (56%) were followed with serial MRI alone (group B). The tumor control rate for the entire group was 77% and 69% at 10- and 15-year, respectively. Upfront radiotherapy (P = 0.25), extent of resection (P = 0.11) or tumor grade (P = 0.83) did not affect tumor control. The majority of Group B patients with recurrent tumors (5/7) obtained tumor control with repeat resection (n = 2), salvage radiotherapy (n = 2), or a combination of both (n = 1). The 10-year disease-specific survival was 95% with no difference between the group A and B (P = 0.50).

CONCLUSION

For patients with grade I/II SBC, a reasonable strategy is deferral of radiotherapy after maximum safe resection until tumor progression or recurrence. At that time, most patients can be successfully managed with salvage radiotherapy or surgery. Late recurrences may occur, and life-long follow-up is advisable.

A new method for quantification and 3D visualization of brain tumor adhesion using slip interface imaging in patients with meningiomas

OBJECTIVES

To develop an objective quantitative method to characterize and visualize meningioma-brain adhesion using MR elastography (MRE)-based slip interface imaging (SII).

METHODS

This retrospective study included 47 meningiomas (training dataset: n = 35; testing dataset: n = 12) with MRE/SII examinations. Normalized octahedral shear strain (NOSS) values were calculated from the acquired MRE displacement data. The change in NOSS at the tumor boundary (ΔNOSS_bdy) was computed, from which a 3D ΔNOSS_bdy map of the tumor surface was created and the probability distribution of ΔNOSS_bdy over the entire tumor surface was calculated. Statistical features were calculated from the probability histogram. After eliminating highly correlated features, the capability of the remaining feature for tumor adhesion classification was assessed using a one-way ANOVA and ROC analysis.

RESULTS

The magnitude and location of the tumor adhesion can be visualized by the reconstructed 3D ΔNOSS_bdy surface map. The entropy of the ΔNOSS_bdy histogram was significantly different between adherent tumors and partially/completely non-adherent tumors in both the training (AUC: 0.971) and testing datasets (AUC: 0.900). Based on the cutoff values obtained from the training set, the ΔNOSS_bdy entropy in the testing dataset yielded an accuracy of 0.83 for distinguishing adherent versus partially/non-adherent tumors, and 0.67 for distinguishing non-adherent versus completely/partially adherent tumors.

CONCLUSIONS

SII-derived ΔNOSS_bdy values are useful for quantification and classification of meningioma-brain adhesion. The reconstructed 3D ΔNOSS_bdy surface map presents the state and location of tumor adhesion in a "clinician-friendly" manner, and can identify meningiomas with a high risk of adhesion to adjacent brain parenchyma.

KEY POINTS

• MR elastography (MRE)-based slip interface imaging shows promise as an objective tool to preoperatively discriminate meningiomas with a high risk of intraoperative adhesion. • Measurement of the change of shear strain at meningioma boundaries can provide quantitative metrics depicting the state of adhesion at the tumor-brain interface. • The surface map of tumor adhesion shows promise in assisting precise adhesion localization, using a comprehensible, "clinician-friendly" 3D visualization.

Clinical, biological, radiological, and pathological comparison of sparsely and densely granulated somatotroph adenomas: a single center experience from a cohort of 131 patients with acromegaly

PURPOSE

Growth hormone-producing pituitary adenomas are divided into two clinically relevant histologic subtypes, densely (DG-A) and sparsely (SG-A) granulated. Histologic subtype was evaluated in a large cohort of patients with acromegaly, separating DG-A and SG-A, and correlated with clinicopathological characteristics.

METHODS

Patients with acromegaly undergoing surgery as initial therapy between 1995 and 2015 were identified. Histologic subtype was determined by keratin expression pattern with CAM5.2 and correlated with clinical and imaging parameters, somatostatin receptor subtype 2 (SST2) expression, post-surgical remission rate, and application of a prognostic scoring system incorporating proliferation and invasiveness.

RESULTS

One hundred thirty-one patients were included. Tumors were classified as DG-A (75, 57.3%), SG-A (29, 22.1%), intermediate (I-A) (9, 6.9%), and unclassified (18, 13.7%) when CAM5.2 was negative. DG-A and I-A were combined for analysis (DG/I-A) and compared to SG-A. Age, gender, proliferation, and post-surgical remission did not differ. SG-A were larger [2 vs. 1.5 cm (median), p = 0.03], more frequently invasive [65.5% vs. 32.9%, p = 0.004], associated with higher MRI T2-weighted signal ratio [1.01 vs. 0.82 (median), p = 0.01], showed lower SST2 expression (p < 0.0001), and scored higher in the prognostic classification (p = 0.004). Surgical remission occurred in 41.7% DG/I-A and 41.4% SG-A (p = 1.0). On multivariate analysis, absence of invasion (p = 0.009) and lower pre-operative IGF-1 index (p = 0.0002) were associated with post-surgical remission.

CONCLUSION

CAM5.2 allowed distinction between DG/I-A and SG-A in most but not all cases. Histologic subtype did not predict surgical outcome. Absence of invasion and lower pre-operative IGF-1 index were the only significant predictors of post-surgical remission in this cohort.

Aneurysmal Bone Cysts of the Paranasal Sinuses: The Mayo Clinic Experience and Review of the Literature

OBJECTIVE/HYPOTHESIS

Aneurysmal bone cysts (ABCs) are benign, lytic bone lesions, which rarely present in the paranasal sinuses. There is no published consensus on the appropriate diagnostic or treatment approach. Our objective was to elucidate the clinical behavior, treatment, and outcomes for patients with ABCs of the paranasal sinuses (psABCs).

STUDY DESIGN

Retrospective case series and system review of the literature.

METHODS

A retrospective chart review was performed to identify patients evaluated at the authors' institution with psABC and consolidated with literature reports of psABC.

RESULTS

Eighty-nine patients met inclusion criteria. The most common presenting symptom was painless facial swelling (n = 35, 39%). The ethmoid sinuses were the most common site involved (n = 55, 62%). Surgical approach was reported in 74 cases including 20 endoscopic and 54 with an open or combined approach. Fifty-nine patients (71%) underwent gross total resection. Follow up data was reported for 67 patients. Fifteen patients (22%) were found to have recurrence or progression at follow up; 10/15 (66%) patients within the first 12 months, 14/15 (93%) within the first 24 months, and 1/15 (7%) greater than 24 months after treatment. Patients were more likely to have recurrence/progression if they presented with nasal discharge (P = .05), proptosis (P = .01), or orbital involvement (P = .03).

CONCLUSIONS

psABCs typically present with painless swelling or nasal obstruction. Orbital involvement is a negative prognostic indicator with these patients more likely to have recurrence after treatment. Recurrence or progression of disease is most likely to occur within 2 years after treatment. Therefore, patients should be monitored closely during this time.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E2525-E2533, 2021.

Pituitary adenomas in the setting of multiple endocrine neoplasia type 1: a single-institution experience

OBJECTIVE

Multiple endocrine neoplasia type 1 (MEN1) is a rare, autosomal-dominant tumor disorder characterized by the development of pituitary tumors and other endocrine neoplasms. Diagnosis is made clinically based on the development of 2 or more canonical lesions (parathyroid gland, anterior pituitary, and enteropancreatic tumors) or in family members of a patient with a clinical diagnosis of MEN1 and the occurrence of one of the MEN1-associated tumors. The goal of this study was to characterize pituitary tumors arising in the setting of MEN1 at a single institution. The probability of tumor progression and the likelihood of surgical intervention in patients with asymptomatic nonfunctional pituitary adenomas were also analyzed.

METHODS

A retrospective review of a prospectively maintained institutional database was performed for patients with MEN1 diagnosed from 1970 to 2017. Data included patient demographics, tumor characteristics, treatment strategies, and outcomes.

RESULTS

A review of the database identified 268 patients diagnosed with MEN1, of whom 158 (59%) were female. Among the 268 patients, 139 (51.8%) had pituitary adenomas. There was a higher prevalence in women than in men (65% vs 35%, p < 0.005). Functional adenomas (57%) were more common. Prolactin-secreting adenomas were the most common functional tumors. Macroadenomas were seen in 27% of patients and were more likely to be symptomatic and locally aggressive (p < 0.001). Forty-nine patients (35%) underwent transsphenoidal resection at some point during their disease course. In 52 patients who were initially observed with MEN1 asymptomatic nonfunctional adenomas, only 5 (10%) progressed to need surgery. In MEN1 patients, an initial parathyroid lesion is most likely followed in order by pituitary, pancreatic, adrenal, and, finally, rare carcinoid tumors.

CONCLUSIONS

Asymptomatic nonfunctional pituitary adenomas in patients with MEN1 may be followed safely with MRI. In this series, parathyroid tumors developed at the lowest median age of all cardinal tumors, and development of additional cardinal MEN1 lesions followed a predictable pattern. This pattern of disease progression could have significant implications for disease surveillance in clinical practice and may help to target clinical resources to the lesions most likely to develop next. This may aid with early detection and treatment and warrants further study.

Collision of Craniopharyngioma and Pituitary Adenoma: Comprehensive Review of an Extremely Rare Sellar Condition

OBJECTIVE

The collision of pituitary adenoma and craniopharyngioma is extremely rare and thus there remains a paucity of data.

METHODS

We described a patient from our institution. We also performed a systematic review and subsequent quantitative synthesis of the literature (n = 21) and our institutional case to yield an integrated cohort, and a descriptive analysis was carried out.

RESULTS

Twenty-two patients (15 males and 7 females) were included in the integrated cohort. The median age was 47.0 years (range, 8-75 years). The tumor subtypes were 5 somatotropic, 5 lactotropic, 4 nonfunctioning, 3 gonadotropic, 2 corticotropic, 1 plurihormonal, and 1 silent subtype 3 for pituitary adenomas, and 19 adamantinomatous, 2 papillary, and 1 unknown subtype for craniopharyngiomas. Three different radiographic patterns were observed: solid mass with cystic component (n = 5), coexistence of two distinct solid components (n = 3), and a mixed-intensity solid mass (n = 5). The first 2 were consistent with histologically separate collision, whereas the third was consistent with histologically admixed collision. Among 19 patients in whom the postoperative course was recorded, a secondary intervention was required in 14 (73.7%) because of tumor progression or residual. The recurrence rate after gross total resection was 33.3%. Postoperative hormone replacement was required in 33.3%. The 10-year cumulative overall survival was 73.1%.

CONCLUSIONS

Most craniopharyngiomas were adamantinomatous. There are 2 types of collisions: separated and admixed. Tumor control, overall survival, and endocrinologic remission are more challenging to achieve than for solitary tumors, but gross total resection of both tumors is important for satisfactory tumor control.

Fluorescence guided surgery for pituitary adenomas

PURPOSE

Resection of pituitary adenomas presents a number of unique challenges in neuro-oncology. The proximity of these lesions to key vascular and endocrine structures as well as the need to interpret neuronavigation in the context of shifting tumor position increases the complexity of the operation. More recently, substantial advances in fluorescence-guided surgery have been demonstrated to facilitate the identification of numerous tumor types and result in increased rates of complete resection and overall survival.

METHODS

A review of the literature was performed, and data regarding the mechanism of the fluorescence agents, their administration, and intraoperative tumor visualization were extracted. Both in vitro and in vivo studies were assessed. The application of these agents to pituitary tumors, their advantages and limitations, as well as future directions are presented here.

RESULTS

Numerous laboratory and clinical studies have described the use of 5-ALA, fluorescein, indocyanine green, and OTL38 in pituitary lesions. All of these drugs have been demonstrated to accumulate in tumor cells. Several studies have reported the successful use of the majority of the agents in inducing intraoperative tumor fluorescence. However, their sensitivity and specificity varies across the literature and between functioning and non-functioning adenomas.

CONCLUSIONS

At present, numerous studies have shown the feasibility and safety of these agents for pituitary adenomas. However, further research is needed to assess the applicability of fluorescence-guided surgery across different tumor subtypes as well as explore the relationship between their use and postoperative clinical outcomes.