Endoscopic Endonasal Approach for Resection of a Recurrent Craniopharyngioma: Techniques to Maximize Surgical Exposure and Extent of Resection.

Craniopharyngiomas are challenging tumors of the central nervous system that originate from epithelial remnants of the Rathke pouch.1-3 Despite maximum safe resection, these tumors present a high tendency to recur (∼20%-40%), even after apparent gross total resection.1,2 The management of recurrent craniopharyngiomas is more challenging, associated with a higher risk of permanent morbidity and complications.1,3 The endoscopic endonasal approach is an option for recurrent tumors, especially in the presence of a previous transcranial approach.1,3-7 In Video 1, we present a case of a 63-year-old man with a recurrent craniopharyngioma with a 2-month history of visual decline, confusion, impaired memory, and episodes of urinary incontinence. On physical examination, he presented slow speech, word-finding difficulties, and left homonymous hemianopsia. Magnetic resonance imaging evidenced a large suprasellar, retrochiasmatic mass with solid (calcified) and cystic components with interval progression compared with previous scans. Treatment options were discussed, and the patient consented to undergo maximum safe resection through an extended endoscopic endonasal approach. Surgical techniques are presented side by side with anatomic dissections to illustrate key steps of the procedure. The patient tolerated the procedure well, with gross total resection of the tumor and without complications or postoperative cerebrospinal fluid leaks. He was subsequently discharged home on postoperative day 5 with continued hormonal replacement therapy. On follow-up, the patient presented marked improvement in his cognitive function. The patient gave informed consent for the use of their images.

Machine Learning Models to Forecast Outcomes of Pituitary Surgery: A Systematic Review in Quality of Reporting and Current Evidence.

BACKGROUND: The complex nature and heterogeneity involving pituitary surgery results have increased interest in machine learning (ML) applications for prediction of outcomes over the last decade. This study aims to systematically review the characteristics of ML models involving pituitary surgery outcome prediction and assess their reporting quality. METHODS: We searched the PubMed, Scopus, and Web of Knowledge databases for publications on the use of ML to predict pituitary surgery outcomes. We used the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) to assess report quality. Our search strategy was based on the terms "artificial intelligence", "machine learning", and "pituitary". RESULTS: 20 studies were included in this review. The principal models reported in each article were post-surgical endocrine outcomes (n = 10), tumor management (n = 3), and intra- and postoperative complications (n = 7). Overall, the included studies adhered to a median of 65% (IQR = 60-72%) of TRIPOD criteria, ranging from 43% to 83%. The median reported AUC was 0.84 (IQR = 0.80-0.91). The most popular algorithms were support vector machine (n = 5) and random forest (n = 5). Only two studies reported external validation and adherence to any reporting guideline. Calibration methods were not reported in 15 studies. No model achieved the phase of actual clinical applicability. CONCLUSION: Applications of ML in the prediction of pituitary outcomes are still nascent, as evidenced by the lack of any model validated for clinical practice. Although studies have demonstrated promising results, greater transparency in model development and reporting is needed to enable their use in clinical practice. Further adherence to reporting guidelines can help increase AI's real-world utility and improve clinical practice.

Smell Outcomes in Olfactory Groove Meningioma Resection Through Unilateral versus Bilateral Transcranial Approaches: A Systematic Review and Meta-analysis.

OBJECTIVE: Olfactory disturbance is a common complication that occurs following the surgical resection of olfactory groove meningiomas (OGMs). There is little evidence on the best transcranial approach that minimizes rates of postoperative olfactory disturbance. The objective of this systematic review and meta-analysis is to compare smell outcomes after OGM resection in unilateral versus bilateral transcranial approaches. METHODS: A systematic review of the literature and meta-analysis was conducted using PUBMED, SCOPUS, and EMBASE in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The primary endpoint was incidence of new olfactory disturbance defined as anosmia or hyposmia, or both. Patients were classified as undergoing either a unilateral or bilateral approach. Data on presence of new postoperative olfactory deficits were used to generate standardized mean differences and 95% confidence intervals. RESULTS: Ten studies met the inclusion criteria for quantitative analysis, comprising 342 patients. A total of 216 patients underwent unilateral approaches while 126 underwent resection via bilateral approach. In the unilateral approach cohort, 17.1% experienced new postoperative olfactory disturbance following resection, compared with 19.2% of patients in the bilateral approach cohort. Forest plot did not reveal any significant difference in the incidence of new olfactory disturbance following either unilateral or bilateral approaches. CONCLUSIONS: Our data suggest that there is no significant difference between the investigated transcranial approaches and postoperative olfactory disturbances. Accordingly, our study suggests that further investigation with introduced experimental control could provide more insight into the capabilities and drawbacks of each route in relation to olfactory outcomes.

Can Diffusion-Weighted Imaging Serve as an Imaging Biomarker for Acute Bacterial Rhinosinusitis?

Acute rhinosinusitis is defined as symptomatic inflammation of the mucosal lining of the nasal cavity and paranasal sinuses lasting less than four weeks. It is most commonly secondary to viral infection but is often challenging to distinguish from bacterial etiologies. Even with recommendations from several specialty societies, there continues to be a frequent practice of overprescribing oral antibiotics for acute rhinosinusitis, thus leading to multidrug-resistant organisms, and rendering oral medication useless when actually clinically warranted. We observed a potential non-invasive imaging biomarker that could predict which patients would benefit from anti-microbial therapy. Often computed tomography (CT) imaging is obtained by the provider before consultation with the otolaryngologist, sometimes leading to unnecessary radiation to the patient. In addition, there are no clear CT findings to make the diagnosis of acute rhinosinusitis. The diagnosis is challenging for all clinicians involved, and therefore, additional signs on other imaging modalities would be helpful. We present a series of four patients with incidentally discovered culture-positive acute rhinosinusitis. Patients with incidentally discovered culture-positive acute rhinosinusitis were found to also have magnetic resonance imaging (MRI) that showed corresponding restricted diffusion on diffusion-weighted imaging (DWI). An imaging biomarker for acute bacterial rhinosinusitis may improve the appropriate use of antibiotic therapy. DWI MRI should be further investigated as a potential candidate screening modality.

Endoscopic endonasal transclival approach to the ventral brainstem: Radiologic, anatomic feasibility and nuances, surgical limitations and future directions.

The endoscopic endonasal transclival approach (EETA) is less invasive than traditional open approaches; however, there is currently limited data on the pre-operative features that may predict success of the EETA. Surgical landmarks and exposure of the EETA and expanded EETA are assessed. We retrospectively measured multiple anatomic features in 154 adult dry skulls, 22 C1 and C2 dry bone vertebrae, and 500 paranasal sinus computed tomography (CT) scans. We also dissected 13 formalin-fixed, silicone-injected adult cadaveric heads. Relevant qualitative and quantitative data were obtained with CT (n = 10) and cadaveric dissection (n = 13). They are expressed as mean (SD), as appropriate and compared with unpaired t tests. Categorical variables were compared with χ2 tests. We determined the prevalence of clival and sphenoid sinus anatomic variations and assessed potential exposure of the craniovertebral region, based on the relative position of the nasal bone tip, posterior point of the hard palate, and their relation to the position of C1 and C2. Depending on anatomic features, EETA should allow visualization of the ventral brainstem. The mean (SD) dimensions of the surgical window for EETA were 43.2 (5.1) × 18.3 (1.1) mm, in the craniocaudad and horizontal dimensions, respectively. The craniocaudad dimension enlarged to 60.2 (4.7) mm with expanded EETA. The EETA allowed satisfactory exposure for odontoid and C1 anterior arch resection (expanded EETA) in all specimens, regardless of the orientation of the palate. The combination of preoperative radiographic assessment and intraoperative considerations allows safe and effective application and facilitate selection of the most appropriate approach.

Vestibular perception and the vestibulo-ocular reflex in young and older adults.

OBJECTIVES: Quantification of the perceptual thresholds to vestibular stimuli may offer valuable complementary information to that provided by measures of the vestibulo-ocular reflex (VOR). Perceptual thresholds could be particularly important in evaluating some subjects, such as the elderly, who might have a greater potential of central as well as peripheral vestibular dysfunction. The authors hypothesized that perceptual detection and discrimination thresholds would worsen with aging, and that there would be a poor relation between thresholds and traditional measures of the angular VOR represented by gain and phase on rotational chair testing. DESIGN: The authors compared the detection and discrimination thresholds of 19 younger and 16 older adults in response to earth-vertical, 0.5 Hz rotations. Perceptual results of the older subjects were then compared with the gain and phase of their VOR in response to earth-vertical rotations over the frequency range from 0.025 to 0.5 Hz. RESULTS: Detection thresholds were found to be 0.69 ± 0.29 degree/sec (mean ± standard deviation) for the younger participants and 0.81 ± 0.42 degree/sec for older participants. Discrimination thresholds in younger and older adults were 4.83 ± 1.80 degree/sec and 4.33 ± 1.57 degree/sec, respectively. There was no difference in either measure between age groups. Perceptual thresholds were independent of the gain and phase of the VOR. CONCLUSIONS: These results indicate that there is no inevitable loss of vestibular perception with aging. Elevated thresholds among the elderly are therefore suggestive of pathology rather than normal consequences of aging. Furthermore, perceptual thresholds offer additional insight, beyond that supplied by the VOR alone, into vestibular function.

Human discrimination of rotational velocities.

Vestibular reflexes are critically important for stabilizing gaze and maintaining posture, but comparatively little is known about conscious perceptions of vestibular stimuli and how they may relate to balance function. We used psychophysical methods to determine the ability of normal subjects and a vestibular-deficient subject to discriminate among velocities of earth-vertical sinusoidal rotations. Discrimination thresholds in normal subjects rose from 2.26 deg/s at a peak velocity of 20 deg/s up to 5.16 deg/s at 150 deg/s. The relationship between threshold and peak angular velocity was well described by the power law function DeltaI = 0.88I(0.37), where I is the magnitude of the stimulus and DeltaI is the discrimination threshold. The subject with bilateral vestibular hypofunction had thresholds more than an order of magnitude worse than normals. The performance of normal subjects is much better than that predicted by Weber's Law, which states that discrimination thresholds increase proportionally with stimulus magnitude (i.e., DeltaI/I = C, where C is the "Weber fraction"). This represents a remarkable exception to other sensory systems and may reflect the vestibular system's ability to stabilize gaze and maintain posture even at high stimulus intensities. Quantifying this relationship may help elucidate the role of higher-level processes in maintaining balance and provide information to diagnose and guide therapy of patients with central causes for imbalance.