Pituitary Apoplexy in Macroadenoma After Minor Surgery: An Unusual Case and Literature Review

Pituitary apoplexy is a rare and severe complication of pituitary adenoma that may present with new-onset headache, ocular palsy, visual disturbances, life-threatening electrolyte imbalance, and endocrinological disturbances due to pituitary hemorrhage and/or infarction. We report the case of a 58-year-old previously healthy patient who developed isolated mild oculomotor nerve palsy of the left eye following osteosynthesis of a traumatic right distal radius fracture. Initial cerebral magnetic resonance imaging showed a pituitary macroadenoma without characteristic signs of pituitary infarction or hemorrhage. The patient presented to the neurology department on the fifth postoperative day with malaise and fatigue due to pituitary insufficiency, deteriorated rapidly and required intensive care monitoring. Clinical stabilization was achieved through the administration of hydrocortisone, and transsphenoidal resection of the pituitary lesion was performed on the 10th day after acute symptom onset. Histological examination revealed a necrotic pituitary adenoma. Pituitary apoplexy may occur after minor surgery in patients with pituitary adenoma. Clinicians should pay particular attention to laboratory signs of pituitary insufficiency in new-onset oculomotor nerve palsy associated with sellar lesions, as cerebral imaging may miss pituitary apoplexy and therefore delay diagnosis and treatment. In our case, delayed decompressive transsphenoidal resection resulted in the normalization of the oculomotor nerve palsy while the pituitary insufficiency persisted. The potential impact of an earlier surgical intervention on the outcome of pituitary function remains uncertain.

Meningeal Metastasis Causing Chronic Subdural Hematoma in a Cancer Patient with Bilateral Papilledema and Suspected Cerebral Venous Thrombosis: A Case Report

Meningeal metastasis has been reported as a very rare cause of chronic subdural hematoma (CSH). Here, we report a female patient who had undergone initial burr hole drainage of a CSH at an outside hospital. Postoperatively, the patient additionally suffered from visual impairment due to bilateral papilledema and the patient was eventually transferred to our neurosurgical department for additional treatment. A craniotomy was performed and due to intraoperative suspicious findings, histopathologic samples were obtained that revealed a metastasis of thus far undiagnosed triple negative breast cancer. Furthermore, the patient was suspected to have a partial cerebral venous thrombosis (CVT). Our case report addresses this extremely rare clinical constellation. We provide a detailed overview on our patient's clinical and radiologic course, and discuss the potential association of CSH with meningeal metastasis and bilateral papilledema.

Radiation-Induced Brachial Plexopathy (RIBP) after Stereotactic Body Radiotherapy (SBRT): Pooled Analyses of Risks

PURPOSE/OBJECTIVE(S)

RIBP, with symptomatic upper extremity motor or sensory deficits, is a risk after SBRT. We herein model dosimetric factors associated with risks of RIBP of the inferior aspect of the brachial plexus following SBRT for apical lung tumors.

MATERIALS/METHODS

Literature searches (PubMed & Embase databases) were performed to identify reports published from 2000-2021, using search criteria of ["brachial plex*" and stereotactic]. From a PRISMA systematic review, studies were identified that included individual patient data on: (1) RIBP endpoints after SBRT for apical lung tumors; and (2) brachial plexus Dmax, or maximum point doses (i.e., D0.035cc or D0.03cc). These data were amenable to normal tissue complication probability (NTCP) modelling. Doses were converted using the linear-quadratic model with an alpha-beta ratio of 3 Gy. For the probit models, the parameter values were determined using the maximum likelihood method and the 95% confidence intervals (CI) were determined using the profile likelihood method. The ability of the NTCP models to distinguish patients with and without RIBP was evaluated using the area under the curve (AUC).

RESULTS

Two probit NTCP models were derived: one from 3 studies (185 patients with 192 targets and 11 events) and another from 4 studies (221 patients with 229 targets and 18 events). NTCP models (summarized in table) suggest ≈10% risks associated with brachial plexus maximum dose (Dmax) of ∼32-34 Gy in 3 fractions and ∼40-43 Gy in 5 fractions, with a clear dose response. These dose-responses with SBRT (with steep dose gradients beyond the target volume and thus only partial-irradiation of the brachial plexus) are far less steep than those reported following conventionally-fractionated or moderately-hypofractionated radiotherapy used for breast, lung and head and neck cancers (that tend to use radiotherapy fields that circumferentially irradiate the brachial plexus).

CONCLUSION

A dose-response for risk of RIBP after SBRT is observed relative to brachial plexus Dmax. The less-steep dose-response compared to that seen from conventionally-fractionated or moderately-hypofractionated radiotherapy (with large irradiated plexus volumes) suggest a possible volume dependence of RIBP risks. Future work should focus on understanding possible volume effects.

Mammalian enamel: A universal tissue and diverse source of inspiration

The natural armors and weapons of the animal kingdom are serving as inspiration in the development of next-generation engineering materials. In this pursuit, seldom considered are the variations in properties across taxa that have evolved to meet their unique functional demands. Here, teeth from six different mammalian species were acquired and categorized according to their bite force quotient (BFQ), which accounts for the allometric scaling between bite force and body size. Selected chemical, microstructural, and mechanical properties of the enamel were quantified across the enamel thickness using spectroscopy and indentation techniques. Results showed that the chemical composition of enamel was significantly (P <  0.05) different between the Low and High BFQ groups, whereas the apatite crystallinity was not. The enamel of all animals exhibited a spatial gradient in mechanical properties that was consistent when evaluated using a normalized framework. Although the elastic modulus, hardness and indentation brittleness were significantly lower in the High BFQ group, the fracture resistance of enamel was significantly higher in this group, potentially reflective of bite force requirements related to diet and predation. Enamel rod decussation was present in all teeth, but there were differences in specific microstructural features. Overall, these results highlight that the diversity of tooth enamel across species should be considered in the pursuit of nature-inspired structural materials. STATEMENT OF SIGNIFICANCE: Natural weapons are serving as inspiration in the development of next-generation engineering materials. Tooth enamel is a viable candidate, but variations in the structure and properties of enamel across taxa have not been explored. Here, teeth from six different mammalian species were categorized according to their bite force quotient (BFQ), and the enamel was compared in terms of selected chemical, microstructural, and mechanical properties. We show that specific aspects of the chemical composition and properties of the Low and High BFQ groups are unique, which appears reflective of bite forces associated with diet and predation. Overall, the results highlight that the diversity of tooth enamel across species should be considered in the pursuit of nature-inspired structural materials.

Tetravalent Influenza Vaccine Is Not Associated With Neuroaxonal Damage in Multiple Sclerosis Patients

Background

Efficacy of vaccines and disease activity linked to immunization are major concerns among people with multiple sclerosis (pwMS).

Objective

To assess antibody responses to seasonal influenza antigens and vaccine-associated neuroaxonal damage utilizing serum neurofilament light chain (sNfL) in pwMS receiving dimethyl fumarate (DMF).

Methods

In this prospective study, the 2020/2021 seasonal tetravalent influenza vaccine was administered to 20 pwMS treated with DMF and 15 healthy controls (HCs). The primary endpoints were responder rate of strain-specific antibody production (seroconversion or significant (4-fold) increase in influenza-antibody titers for ≥2/4 strains) at 30 days post-vaccination and changes in sNfL levels.

Results

All patients treated with DMF fulfilled the responder criteria for immunization compared with 53% of the controls. However, higher proportions of HCs already had influenza-antibody titers ≥1:40 at baseline (53% vs. 41%, p = 0.174). sNfL levels were comparable among both groups at baseline and did not increase 34 days after vaccination. In addition, no clinical or radiological disease reactivation was found.

Conclusion

DMF-treated patients mount an adequate humoral immune response to influenza vaccines. Within the limits of the small cohort investigated, our data suggest that influenza immunization is not associated with clinical or subclinical disease reactivation.

Liver stiffness assessed by shear-wave elastography declines in parallel with immunoregulatory proteins in patients with chronic HCV infection during DAA therapy

BACKGROUND

A rapid decline of liver stiffness (LS) was detected by non-invasive methods in patients with chronic hepatitis C (HCV) infection during treatment with direct-acting antivirals (DAA).

OBJECTIVE

To investigate the influence of inflammation on LS.

METHODS

We prospectively examined LS by sonographic shear-wave elastography in 217 patients during DAA therapy from treatment initiation (BL) to 12 weeks after end of therapy (SVR12). Demographic data, laboratory findings and serum levels of cytokines were determined.

RESULTS

Values of LS decreased from 1.86 m/s to 1.68 m/s (p = 0.01) which was most pronounced in patients who had F4 fibrosis at BL (3.27 m/s to 2.37 m/s; p <  0.001). Initially elevated values of aminotransferases, ferritin, IgG (p <  0.001 each) and international normalized ratio (p <  0.003) declined, thrombocyte count (p = 0.007) increased. Correlations of these laboratory parameters with BL levels of LS measurement (LSM) were most apparent in patients with F1-F3 fibrosis. Tumor necrosis factor (TNF)-α (p = 0.031), interleukin (IL)-10 (p = 0.005) and interferon y inducible protein (IP)-10 (p <  0.001) decreased in parallel with LSM under DAA therapy and corelated with BL values.

CONCLUSION

Decrease of systemic inflammatory parameters correlated with LSM under DAA therapy. We conclude that regression of LSM is attributable to the decline of inflammation rather than reflecting fibrosis.

Evaluation of a novel flow diverter, the DiVeRt system, in an animal model

BACKGROUND

Using a surgical aneurysm model, this study assessed the performance of a new flow diverter (FD), the DiVeRt, and evaluated the angiographic and histologic features at different periods after stent deployment.

METHODS

Fifteen New Zealand White rabbits were treated 3 days prior to intervention and until euthanization with dual antiplatelets. DiVeRt was implanted in bilateral carotid aneurysms (n=30) as well as in the aorta (n=15). The rate of technical success, assessment of aneurysm occlusion (measured by the O'Kelly-Marotta grading (OKM) scale), and stent patency were examined using angiography and histologic examinations in three groups at 1, 3, and 6 months follow-up (FU). In each FU group one control animal was included and treated with the XCalibur stent (n=3).

RESULTS

Overall, DiVeRt placement was successful and without apparent intraprocedural complications. In total, four stents in the carotid artery were occluded and in-stent stenosis was registered in two carotid (7%) and one aortic (6%) vessels. Complete or near complete aneurysm occlusion (OKM scale D1 and C3) was seen in 100% in the 1-month FU group, 70% in the 2-month FU group, and 100% in the 3-month FU group. Histology showed loose, organizing fibrous tissue matrix within the sac and adequate neck endothelialization in all vessels. All branches covered by the DiVeRt remained patent.

CONCLUSIONS

The DiVeRt system appears to be feasible and effective for the treatment of aneurysms with high rates of complete aneurysm occlusion, excellent vessel patency, and evidence of high biocompatibility. Occurrences of parent artery occlusion at follow-up did not result in clinical consequences.

Fluorescence Emission Triggered by Radioactive β decay in Optimized Hyperbolic Cavities

Luminescence arising from β -decay of radiotracers has garnered much interest recently as a viable in-vivo imaging technique. The emitted Cerenkov radiation can be directly detected by high sensitivity cameras or used to excite highly efficient fluorescent dyes. Here, we investigate the enhancement of visible and infrared emission driven by β -decay of radioisotopes in the presence of a hyperbolic nanocavity. By means of a transfer matrix approach, we obtain quasi-analytic expressions for the fluorescence enhancement factor at the dielectric core of the metalodielectric cavity, reporting a hundred-fold amplification in periodic structures. A particle swarm optimization of the layered shell geometry reveals that up to a ten-thousand-fold enhancement is possible thanks to the hybridization and spectral overlapping of whispering-gallery and localized-plasmon modes. Our findings may find application in nuclear-optical medical imaging, as they provide a strategy for the exploitation of highly energetic gamma rays, Cerenkov luminescence, and visible and near-infrared fluorescence through the same nanotracer.

Neck-MRI experience for investigation of survived strangulation victims

For the medicolegal evaluation of victims of survived strangulation, a neck-magnetic resonance imaging (MRI) can be performed for assessing lesions in the inner soft tissues (fat, muscles or lymph nodes, for example). In our institute, such MRI examinations have been performed for a test period of 4 years with the aim of evaluating the use of this tool by forensic pathologists and identifying medicolegal indicators for the performance of neck-MRI in surviving victims of strangulation. We retrospectively reviewed medicolegal reports from all victims examined during the test period. We extracted objective lesions (e.g. petechiae, bruising and abrasions) and reported clinical symptoms (e.g. vision disorder, dysphasia) from the reports. These findings were compared to those reported from the neck-MRI. In total, 112 victims were clinically examined after suspected strangulation. Eleven of these victims underwent an MRI examination of the neck. Eighty-four of the victims presented objective lesions during the clinical examination, with eight showing signs of both petechiae and bruising. Neck-MRI was performed in four of these eight victims and three of them showed lesions visible in MRI. Of 76 victims with bruising as the only objective finding, 66 victims described clinical symptoms. Of those 66 victims, seven were examined by MRI and two demonstrated lesions in MRI. When MRI was performed, relevant findings were detected in 45% of the cases. This leads to the suspicion that many more findings could have been detected in the other victims, if an MRI had been performed in those cases. Our results lead us to the conclusion that an MRI examination of victims of suspected strangulation is useful, and strict indications for its application should be established.

Fat-free muscle mass in magnetic resonance imaging predicts acute-on-chronic liver failure and survival in decompensated cirrhosis

Muscle mass seems to be a prognostic marker in patients with liver cirrhosis. However, reported methods to quantify muscle mass are heterogeneous, consented cutoff values are missing, and most studies have used computed tomography. This study evaluated fat-free muscle area (FFMA) as a marker of sarcopenia using magnetic resonance imaging (MRI) in patients with decompensated cirrhosis with transjugular intrahepatic portosystemic shunt (TIPS). The total erector spinae muscle area and the intramuscular fat tissue area were measured and subtracted to calculate the FFMA in 116 patients with cirrhosis by TIPS and MRI. The training cohort of 71 patients compared computed tomography-measured transversal psoas muscle thickness with FFMA. In 15 patients MRI was performed before and after TIPS, and in 12 patients follistatin serum measurements were carried out. The results on FFMA were confirmed in a validation cohort of 45 patients. FFMA correlated with follistatin and transversal psoas muscle thickness and showed slightly better association with survival than transversal psoas muscle thickness. Gender-specific cutoff values for FFMA were determined for sarcopenia. Decompensation (ascites, overt hepatic encephalopathy) persisted after TIPS in the sarcopenia group but resolved in the nonsarcopenia group. Sarcopenic patients showed no clinical improvement after TIPS as well as higher mortality, mainly due to development of acute-on-chronic liver failure. FFMA was an independent predictor of survival in these patients.

CONCLUSION

This study offers an easy-to-apply MRI-based measurement of fat-free muscle mass as a marker of sarcopenia in decompensated patients; while TIPS might improve sarcopenia and thereby survival, persistence of sarcopenia after TIPS is associated with a reduced response to TIPS and a higher risk of acute-on-chronic liver failure development and mortality. (Hepatology 2018;67:1014-1026).

Guidelines on radioiodine therapy for differentiated thyroid carcinoma

Aim: For the examination of the impact on clinical practice of the guidelines for differentiated thyroid carcinoma (DTC), treatment data from the ongoing Multicenter Study Differentiated Thyroid Carcinoma (MSDS) were analyzed. Patients, methods: Patients were randomized to adjuvant external beam radiotherapy (RTx) or no RTx in addition to standard therapy in TNM stages pT4 pN0/1/x M0/x (UICC, 5th ed. 1997). All patients were to receive the same treatment regimen consisting of thyroidectomy, ablative radioiodine therapy (RIT), and a diagnostic 131I whole-body scintigraphy (WBS) 3-4 months after RIT. Results: Of 339 eligible patients enrolled between January 2000 and March 2004, 273 could be analyzed. Guideline recommendations by the German Society for Nuclear Medicine from 1999 and 1992 were complied with within 28% and 82% with regard to the interval between surgery and RIT (4 vs. 4–6 weeks), in 33% and 84% with regard to 131I activity for RIT (1-3 vs. 1-4 GBq; ± 10%), and in 16% and 60% with regard to 131I activity for WBS (15319-300 vs. 15319-400 MBq; ± 10%). Conclusions: The 1999 guideline revision appears to have had little impact on clinical practice. Further follow-up will reveal if guideline compliance had an effect on outcomes.

Mapping in-vivo optic nerve head strains caused by intraocular and intracranial pressures

Although it is well documented that abnormal levels of either intraocular (IOP) or intracranial pressure (ICP) can lead to potentially blinding conditions, such as glaucoma and papilledema, little is known about how the pressures actually affect the eye. Even less is known about potential interplay between their effects, namely how the level of one pressure might alter the effects of the other. Our goal was to measure in-vivo the pressure-induced stretch and compression of the lamina cribrosa due to acute changes of IOP and ICP. The lamina cribrosa is a structure within the optic nerve head, in the back of the eye. It is important because it is in the lamina cribrosa that the pressure-induced deformations are believed to initiate damage to neural tissues leading to blindness. An eye of a rhesus macaque monkey was imaged in-vivo with optical coherence tomography while IOP and ICP were controlled through cannulas in the anterior chamber and lateral ventricle, respectively. The image volumes were analyzed with a newly developed digital image correlation technique. The effects of both pressures were highly localized, nonlinear and non-monotonic, with strong interactions. Pressure variations from the baseline normal levels caused substantial stretch and compression of the neural tissues in the posterior pole, sometimes exceeding 20%. Chronic exposure to such high levels of biomechanical insult would likely lead to neural tissue damage and loss of vision. Our results demonstrate the power of digital image correlation technique based on non-invasive imaging technologies to help understand how pressures induce biomechanical insults and lead to vision problems.

Influence of model based iterative reconstruction algorithm on image quality of multiplanar reformations in reduced dose chest CT

Background

Model-based iterative reconstruction (MBIR) reduces image noise and improves image quality (IQ) but its influence on post-processing tools including maximal intensity projection (MIP) and minimal intensity projection (mIP) remains unknown.

Purpose

To evaluate the influence on IQ of MBIR on native, mIP, MIP axial and coronal reformats of reduced dose computed tomography (RD-CT) chest acquisition.

Material and Methods

Raw data of 50 patients, who underwent a standard dose CT (SD-CT) and a follow-up RD-CT with a CT dose index (CTDI) of 2–3 mGy, were reconstructed by MBIR and FBP. Native slices, 4-mm-thick MIP, and 3-mm-thick mIP axial and coronal reformats were generated. The relative IQ, subjective IQ, image noise, and number of artifacts were determined in order to compare different reconstructions of RD-CT with reference SD-CT.

Results

The lowest noise was observed with MBIR. RD-CT reconstructed by MBIR exhibited the best relative and subjective IQ on coronal view regardless of the post-processing tool. MBIR generated the lowest rate of artefacts on coronal mIP/MIP reformats and the highest one on axial reformats, mainly represented by distortions and stairsteps artifacts.

Conclusion

The MBIR algorithm reduces image noise but generates more artifacts than FBP on axial mIP and MIP reformats of RD-CT. Conversely, it significantly improves IQ on coronal views, without increasing artifacts, regardless of the post-processing technique.

[Not Available]

Based on the Federal Health Survey from 1998, the Augsburg heart attack registry, and the ninth coordinated population prediction, we have estimated the occurrence of heart attacks in Germany up to the year 2050. From the mere demographic perspective - regardless of medical and social influences - we can expect that the need for cardiac care will increase considerably. If we assume that the risk or the frequency of having a heart attack will remain the same, then the number of heart attacks in people aged 25 to over 90 and 35 to under 90 will increase, although the population size of these age groups will decline. The population over 75 years of age will with certainty determine the course of the incidence and prevalence of heart attacks. In addition to standardised incidence and/or prevalence rates, estimations of the absolute number of incidents and/or prevalent cases of the respective target illness have to be included in morbidity predictions in order to avoid misinterpretations.

Advances in post-mortem CT-angiography

Performing a post-mortem multidetector CT (MDCT) scan has already become routine in some institutes of forensic medicine. To better visualize the vascular system, different techniques of post-mortem CT-angiography have been explored, which can essentially be divided into partial- and whole-body angiography techniques. Probably the most frequently applied technique today is the so-called multiphase post-mortem CT-angiography (MPMCTA) a standardized method for investigating the vessels of the head, thorax and abdomen. Different studies exist, describing its use for medicolegal investigations, and its advantages as well as its artefacts and pitfalls. With the aim to investigate the performance of PMCTA and to develop and validate techniques, an international working group was created in 2012 called the "Technical Working Group Post-mortem Angiography Methods" (TWGPAM). Beyond its primary perspective, the goals of this group include creating recommendations for the indication of the investigation and for the interpretation of the images and to distribute knowledge about PMCTA. This article provides an overview about the different approaches that have been developed and tested in recent years and an update about ongoing research in this field. It will explain the technique of MPMCTA in detail and give an outline of its indications, application, advantages and limitations.