MRI surveillance after translabyrinthine vestibular schwannoma resection and cochlear implantation: is it feasible?

PURPOSE

Cochlear implantation in patients with vestibular schwannomas is of increasing importance and interest. Two remaining challenges are the assessment of conduction of the cochlear nerve and the possibility of postoperative surveillance with magnetic resonance imaging. The aim of the current study was to assess follow-up imaging and determine the visibility of the internal auditory canal after vestibular schwannoma resection and cochlear implantation as well as in patients with persistent vestibular schwannomas and cochlear implants in place. Visibility of the internal auditory canal, cerebellopontine angle, and labyrinth were evaluated and graded.

METHODS

For this retrospective study, 15 MR examinations of 13 patients after translabyrinthine vestibular schwannoma resection and ipsilateral cochlear implantation were included. All patients had been implanted with an MED-EL cochlear implant. Magnetic resonance imaging was carried out on a 1.5T device. All patients were prepped according to the manufacturer's recommendations.

RESULTS

All 15 examinations were carried out without any adverse event during imaging, such as pain, magnet dislocation, or malfunction. The internal auditory canal and the cerebellopontine angle were sufficiently visible in all cases to allow for vestibular schwannoma follow-up.

CONCLUSION

Magnetic resonance imaging surveillance of the internal auditory canal following vestibular schwannoma resection and cochlear implantation is feasible and safe with modern implants with a 1.5T magnetic resonance imaging device using metal artifact reduction sequences. Necessary follow-up imaging should not be a contraindication for cochlear implantation in patients with vestibular schwannomas.

Intrathoracic pouch migration in one-anastomosis gastric bypass with and without hiatoplasty: A 3-dimensional-computed tomography volumetry study

BACKGROUND

Currently, 4.8% of bariatric operations worldwide are one-anastomosis gastric bypass (OAGB) procedures. If a hiatal hernia is detected in a preoperative gastroscopy, OAGB can be combined with hiatoplasty. Intrathoracic pouch migration (ITM) is common after bypass procedures because the fundus, a natural abutment, is separated from the pouch.

OBJECTIVE

The aim of this study was to find out whether OAGB or OAGB combined with hiatoplasty carries a higher risk of ITM and, therefore, also gastroesophageal reflux disease (GERD).

SETTING

University hospital.

METHODS

Fifty patients (group 1: 25× primary OAGB; group 2: 25× primary OAGB with hiatoplasty) were included in this study. History of weight, GERD, and quality of life were recorded in patient interviews and pouch volume and ITM were evaluated using 3-dimensional-computed tomography volumetry.

RESULTS

There were no differences in terms of patient characteristics, history of weight, pouch volume, or quality of life between both groups. ITM was found in group 1 in 60% (n = 15) and group 2 in 76% (n = 19) of all patients (P = .152). The ITM mean length was significantly lower in group 1 with .9 ± 1.1 cm than in group 2 with 1.8 ± 1.2 cm (P = .007). Regarding GERD, there was no difference between both groups; nevertheless, significantly more patients with ITM (38.2%; n = 13) had GERD compared with patients without ITM (6.3%; n = 1).

CONCLUSION

In primary OAGB, an additional hiatoplasty was not associated with higher rates of ITM or GERD; nevertheless, the length of ITM was higher after hiatoplasty. If ITM occurs, patients have a risk of developing GERD.

Neuroradiological differentiation of white matter lesions in patients with multiple sclerosis and Fabry disease

Objective

White matter lesions (WML) in multiple sclerosis (MS) differ from vascular WML caused by Fabry disease (FD). However, in atypical cases the discrimination can be difficult and may vary between individual raters. The aim of this study was to evaluate interrater reliability of WML differentiation between MS and FD patients.

Materials and methods

Brain MRI scans of 21 patients with genetically confirmed FD were compared to 21 matched patients with MS. Pseudonymized axial FLAIR sequences were assessed by 6 blinded raters and attributed to either the MS or the FD group to investigate interrater reliability. Additionally, localization of WML was compared between the two groups.

Results

The median age of patients was 46 years (IQR 35–58). Interrater reliability was moderate with a Fleiss' Kappa of 0.45 (95%CI 0.3–0.59). Overall, 85% of all ratings in the MS group and 75% in the FD group were correct. However, only 38% of patients with MS and 33% of patients with FD were correctly identified by all 6 raters. WML involving the corpus callosum (p < 0.001) as well as juxtacortical (p < 0.001) and infratentorial lesions (p = 0.03) were more frequently observed in MS patients.

Conclusion

Interrater reliability regarding visual differentiation of WML in MS from vascular WML in FD on standard axial FLAIR images alone is only moderate, despite the distinctive features of lesions in each group.

Rectal preparation significantly improves prostate imaging quality: Assessment of the PI-QUAL score with visual grading characteristics

PURPOSE

To investigate the effects of a rectal preparation regimen, that consisted of a rectal cleansing enema and an endorectal gel filling protocol, on prostate imaging quality (PI-QUAL).

METHODS

Multiparametric MRI (mpMRI) was performed in 150 consecutive patients divided into two groups of 75 patients. One group received a rectal preparation with a cleansing enema and endorectal gel filling (median age 65.3 years, median PSA level 6 ng/ml). The other patient group did not receive such a preparation (median age 64 years, median PSA level 6 ng/ml). Two uroradiologists independently rated general image quality and lesion visibility on diffusion-weighted imaging (DWI), T2-weighted (T2w), and dynamic contrast-enhanced (DCE) images using a five-point ordinal scale. In addition, two uroradiologists assigned PI-QUAL scores, using the dedicated scoring sheet. Data sets were compared using visual grading characteristics (VGC) and receiver operating characteristics (ROC)/ area under the curve (AUC) analysis.

RESULTS

VGC revealed significantly better general image quality for DWI (AUC R1 0.708 (0.628-0.779 CI, p < 0.001; AUC R2 0.687 (0.606-0.760 CI, p < 0.001) and lesion visibility for both readers (AUC R1 0.729 (0.607-0.831 CI, p < 0.001); AUC R2 0.714 (0.590-0.818CI, p < 0.001) in the preparation group. For T2w imaging, rectal preparation resulted in significantly better lesion visibility for both readers (R1 0.663 (0.537-0.774 CI, p = 0.014; R2 0.663 (0.537-0.774 CI, p = 0.014)). Averaged PI-QUAL scores were significantly improved with rectal preparation (AUC R3/R4 0.667, CI 0.581-0.754, p < 0.001).

CONCLUSION

Rectal preparation significantly improved prostate imaging quality (PI-QUAL) and lesion visibility. Hence, a rectal preparation regimen consisting of a rectal cleansing enema and an endorectal gel filling could be considered.

Omalizumab-induced aspirin tolerance in N-ERD patients is independent of atopic sensitization

BACKGROUND

NSAID-exacerbated respiratory disease (N-ERD) comprises the triad of chronic rhinosinusitis with nasal polyps (CRSwNP), asthma and intolerance to inhibitors of the cyclooxygenase-1-enzyme. The impact of omalizumab on prevention of aspirin-induced hypersensitivity in N-ERD patients with and without atopic sensitization has not been thoroughly addressed.

OBJECTIVE

To investigate the effect of omalizumab treatment on aspirin tolerance in atopic and non-atopic N-ERD patients.

METHODS

This single-center, prospective trial evaluated overall omalizumab-induced aspirin tolerability in N-ERD patients by performing aspirin challenge testing before and after 6 months of anti-IgE therapy. The impact of omalizumab on CRSwNP, asthma as well as serum and tissue biomarkers in patients with and without comorbid atopic sensitizations was further analyzed.

RESULTS

Out of 33 patients included in the study, 56% developed complete aspirin tolerance and 18% tolerated higher dosages after 24 weeks. Polyp size and disease-specific symptoms (NPS:-1.9±0.3,p<0.001;SNOT-20:-16.7±3.7,p<0.001;ACT:+3.2±0.7,p<0.001) improved in all patients irrespective of atopic sensitization. Effectiveness of omalizumab was accompanied by an increase in mean total serum IgE (307.8±42kU/L,p<0.001) and a decrease in ECP (-10.6±6.7 μg/L ) and in relative eosinophilia (-2.5±0.7%, p<0.01). While there was a significant reduction of tissue IgE (p<0.05) in all patients after 4 weeks, the number of local eosinophils decreased only in atopic individuals (p<0.05).

CONCLUSION

Omalizumab induced complete aspirin tolerance in the majority (56%) of patients independent of atopic sensitization and demonstrated clinical efficacy in the treatment of CRSwNP and asthma. Inhibition of IgE can therefore be a promising treatment option in preventing NSAID hypersensitivity reactions in N-ERD patients.

Severe gastroparesis after orthotopic heart transplantation

We present a case of severe gastroparesis in a recipient of orthotopic heart transplantation. Although a rare condition after heart transplantation, it is a potential cause of significant morbidity, including vomiting, aspiration and pneumonia. Moreover, impaired gastric emptying alters the pharmacokinetics of immunosuppressive medication with increased risk of severe side effects. Herein, we describe a diagnostic and therapeutic strategy that was successfully applied in a patient with gastroparesis.

Titanium and Platinum-Fluoroplastic Stapes Prostheses Visualization on Cone Beam Computed Tomography and High-Resolution Computed Tomography

Objective: The aim of this study was to evaluate whether stapes prostheses can be visualized with less metal artifacts and therefore more accurately on cone beam computed tomography in comparison to computed tomography imaging. Recent studies have shown that cone beam computed tomography has advantages when imaging metal artifacts. Patients with hearing loss or vertigo, who have undergone stapedotomy, often present a challenge for otologic surgeons. Imaging studies can deliver crucial additional information. Methods: A retrospective analysis of imaging studies and clinical data in a tertiary care center were carried out. Forty-one patients with forty-five implanted ears were evaluated in the study. All included patients had been implanted with a platinum-fluoroplastic (n = 19) or titanium (n = 26) piston and subsequently had undergone imaging months or years after surgery for various reasons. Patients underwent computed tomography or cone beam computed tomography of the temporal bone depending on availability. Piston visualization, prosthesis length, vestibular intrusion and audiologic results were compared between the groups. Piston position on imaging studies were compared to intraoperative findings. Results: Functional length measurements of all prostheses were carried out with a mean error of -0.17 mm (±0.20). Platinum-fluoroplastic protheses were significantly underestimated in length compared to titanium prostheses. To analyze the material-dependent difference in the measurement errors of the imaging techniques the interaction was tested in an ANOVA model and showed no statistically significant result (p = 0.24). The blinded neuroradiologist viewed two implants, both platinum-fluoroplastic pistons, as located outside of the vestibule due to an underestimation of the prothesis length and the missing radiodensity of the lower end of the prosthesis. Conclusion: Surgeons and radiologists should be aware of the different types and radiologic features of stapes prostheses and the missing radiodensity of some protheses parts. Cone beam computed tomography is an imaging alternative with a potential advantage of reduced radiation in patients after stapes surgery suffering from vertigo or hearing loss to evaluate piston position.

[Acute abdomen - a practical approach]

CLINICAL PROBLEM

Acute abdomen describes a critical clinical condition which includes a heterogeneous group of clinical presentations. Several diseases require immediate surgical treatment. Therefore, fast radiological assessment is demanded.

STANDARD RADIOLOGICAL METHODS

Stable patients presenting at the emergency department with acute abdominal pain require an abdominal x‑ray, an ultrasound examination and/or a computed tomography (CT) scan, depending on the location and character of their pain. These standard radiological methods provide a quick differentiation between simple and complicated pathologies. Unstable patients should undergo immediate CT and, if positive, be sent directly to surgery.

METHODICAL INNOVATIONS AND ASSESSMENT

The ongoing technical developments in the field of computed tomography allow a quick and detailed characterization of pathologic conditions of the abdominal organs. A structured approach, based on the analysis of typical radiological signs and patterns, combined with the evaluation of extra-abdominal findings helps to assign the observed imaging findings to specific diseases.

RECOMMENDATION

A systematic 4‑point approach for structured analysis of specific and nonspecific imaging features and common pitfalls aids to choose the correct radiological method and help to narrow the broad spectrum of potential differential diagnoses.

Swallowing MRI-a reliable method for the evaluation of the postoperative gastroesophageal situs after Nissen fundoplication

Purpose

To evaluate the diagnostic performance of swallowing MRI of the gastroesophageal junction (GEJ) in the postoperative care of patients after laparoscopic antireflux surgery (LARS)

Material and methods

In this institutional review board-approved prospective study, 79 symptomatic patients (mean age, 52.3 years; range, 26–80 years) were evaluated after laparoscopic Nissen fundoplication. MRI findings were correlated with revision surgery, endoscopy, and high-resolution manometry (HRM) as standard of reference. MRI was performed on a 3.0-T unit using T2-weighted half-Fourier acquisition single-shot turbo spin echo (HASTE) sequences for anatomical assessment of the GEJ followed by dynamic MR swallowing (fast low-angle shot sequences). Four independent readers (two radiologists, two surgeons) rated 83 MR scans according to defined criteria, such as wrap disruption, slipping, recurrent hiatal hernia, and esophageal motility disorder.

Results

Wrap disruption was correctly diagnosed concordantly with the standard of reference in 87.8%, slipping in 81.5%, and recurrent hiatal hernia in 84.9% of the cases. For esophageal motility disorder, MRI interpretation was consistent with manometry in 66.2% of the subjects. Interobserver analysis showed substantial agreement for recurrent hiatal hernia (k = 0.703), moderate agreement for wrap disruption (k = 0.585), and fair agreement for motility disorder and slipping (k = 0.234 and k = 0.200, respectively).

Conclusion

MR swallowing readily depicts the major failure mechanisms of LARS and has good reliability even in non-experienced readers.

Key Points

• MR swallowing accurately readily depicts the major failure mechanisms of laparoscopic antireflux surgery and has good reliability even in non-experienced readers.

• It should be included in the preoperative workup for revision surgery after fundoplication.

• It will be of great benefit to surgeons in considering and planning a reoperation.

In Vivo Confocal Microscopy in Dry Eye Disease Associated With Chronic Graft-Versus-Host Disease

PURPOSE

To compare densities of corneal epithelial dendritic cells (DCs), corneal subbasal nerves, and conjunctival epithelial immune cells (EICs) between patients with dry eye disease (DED) with and without graft-versus-host disease (GVHD) using in vivo confocal microscopy (IVCM).

METHODS

This study included 54 patients who had moderate to severe DED either associated with (n = 33) or without (n = 21) chronic GVHD. In addition to evaluating clinical parameters of DED, images obtained by laser-scanning IVCM of the central cornea and superior tarsal conjunctiva were analyzed to measure densities of corneal epithelial DCs, corneal subbasal nerves, and conjunctival EICs.

RESULTS

Although there were no significant differences between GVHD and non-GVHD groups in symptom scores, the GVHD group had significantly worse corneal fluorescein staining, tear break-up time, and Schirmer's scores than the non-GVHD group. Corneal epithelial DC density, corneal subbasal nerve density, and conjunctival EIC density were 148 ± 135 cells/mm2, 16.3 ± 6.1 mm/mm2, and 670 ± 267 cells/mm2, respectively, in the GVHD group; and 122 ± 99 cells/mm2, 18.3 ± 5.1 mm/mm2, and 572 ± 271 cells/mm2, respectively, in the non-GVHD group. After adjusting for clinical parameters, including the DED severity, none of the IVCM parameters was significantly different between the GVHD versus non-GVHD groups (P = 0.82, P = 0.21, and P = 0.60, respectively).

CONCLUSIONS

In GVHD-associated DED, cellular changes in the cornea and conjunctiva observed by IVCM were similar to those seen in patients who have non-GVHD dry eye with the same level of disease severity. Therefore, corneal and conjunctival IVCM findings in GVHD-associated DED are possibly reflective of the local disease (DED) severity rather than the underlying systemic disease process.

Reduced Corneal Endothelial Cell Density in Patients With Dry Eye Disease

PURPOSE

To evaluate corneal endothelial cell density (ECD) in patients with dry eye disease (DED) compared to an age-matched control group.

DESIGN

Cross-sectional, controlled study.

METHODS

This study included 90 eyes of 45 patients with moderate to severe DED (aged 53.7 ± 9.8 years) and 30 eyes of 15 normal controls (aged 50.7 ± 9.8 years). All subjects had a complete ophthalmic evaluation including symptom assessment using the Ocular Surface Disease Index (OSDI) and corneal fluorescein staining. In addition, laser scanning in vivo confocal microscopy was performed to measure the density of the following parameters in the central cornea: endothelial cells, subbasal nerves, and subbasal immune dendritic cells.

RESULTS

Corneal ECD was significantly lower in the DED group (2595.8 ± 356.1 cells/mm(2)) than in the control group (2812.7 ± 395.2 cells/mm(2), P = .046). The DED group showed significantly lower corneal subbasal nerve density (17.1 ± 6.9 mm/mm(2)) compared to the control group (24.7 ± 4.4 mm/mm(2), P < .001). Dendritic cell density was significantly higher in the DED group than in the controls (111.7 ± 137.3 vs 32.0 ± 24.4 cells/mm(2), respectively, P = .002). There were statistically significant correlations between corneal ECD and dry eye severity parameters including the OSDI score (rs = -0.26, P = .03), and corneal fluorescein staining (rs = -0.28, P = .008).

CONCLUSIONS

There is a significant reduction in corneal ECD in DED that correlates with clinical severity of the disease.

Effects of corneal nerve density on the response to treatment in dry eye disease

PURPOSE

To evaluate whether levels of corneal subbasal nerve fiber length (SNFL) in dry eye disease (DED) could prognosticate the level of improvement in signs and symptoms after treatment.

DESIGN

Phase IV, double-masked, randomized clinical trial.

PARTICIPANTS

Sixty patients with meibomian gland dysfunction-associated DED and 27 age-matched controls.

METHODS

Patients with DED were randomized to receive topical artificial tears, loteprednol etabonate 0.5%, or loteprednol etabonate 0.5%/tobramycin 0.3% twice daily for 4 weeks. At baseline, in vivo confocal microscopy of central cornea was performed in both eyes. Patients with DED were divided into 2 subgroups: those with low baseline SNFL and those with near-normal baseline SNFL for this purpose (the cutoff point: the mean SNFL in controls minus 2 standard deviations). Clinical signs and symptoms at baseline and after 4 weeks of treatment were compared between the subgroups with low and near-normal SNFL for all therapeutic groups.

MAIN OUTCOME MEASURES

Symptom questionnaires, corneal fluorescein staining (CFS), conjunctival staining with lissamine green, tear break-up time, Schirmer's test, and SNFL.

RESULTS

In patients with DED, baseline SNFL (17.06±5.78 mm/mm(2)) was significantly lower than in controls (23.68±3.42 mm/mm(2), P = 0.001). In the artificial tear and loteprednol groups, although no significant improvement in any sign or symptom was noted in patients with low baseline SNFL (<16.84 mm/mm(2)), subjects with near-normal baseline SNFL (≥16.84 mm/mm(2)) showed significant improvement in both symptoms and CFS score (all P < 0.05). In the loteprednol/tobramycin group, no significant change was evident for any sign or symptom in either subgroup of low or near-normal baseline SNFL.

CONCLUSIONS

Significant improvements in CFS and patient symptomatology after DED treatment were evident only in the subgroup with near-normal corneal SNFL. Consideration of SNFL may assist in explaining the variability of patients' response to DED therapy.