The Development of Neurological Damage in a Patient With Thrombotic Thrombocytopenic Purpura and Legionnaires' Disease: A Case Report.

This case report aims to highlight a rare and severe presentation of Legionnaires' disease complicated by thrombotic thrombocytopenic purpura (TPP). The patient, a 75-year-old male with a history of COVID-19 infection, presented with bilateral pneumonia positive for Legionella pneumophila. He developed signs of TTP, cerebral hemorrhage, and renal failure. Despite treatment, the patient's condition deteriorated, leading to flaccid paralysis, absent reflexes, and multiple brain hemorrhages. This case suggests a potential autoimmune mechanism for the neurological symptoms seen in this combination of Legionnaires' disease and TTP. Thus, it would be worthwhile to further investigate and understand the relationship between these two conditions. Further research into underlying mechanisms will contribute to improving therapeutic approaches for this rare presentation. Additionally, the patient's previous COVID-19 infection could have contributed to thrombotic complications due to its association with respiratory infections, warranting further investigation.

CyberKnife Xsight versus fiducial-based target-tracking: a novel 3D dosimetric comparison in a dynamic phantom.

BACKGROUND: The CyberKnife Xsight lung-tracking system (XLTS) provides an alternative to fiducial-based target-tracking systems (FTTS) for non-small-cell lung cancer (NSCLC) patients without invasive fiducial insertion procedures. This study provides a method for 3D independent dosimetric verification of the accuracy of the FTTS compared to the XLTS without relying on log-files generated by the CyberKnife system. METHODS: A respiratory motion trace was taken from a 4D-CT of a real lung cancer patient and applied to a modified QUASAR™ respiratory motion phantom. A novel approach to 3D dosimetry was developed using Gafchromic EBT3 film, allowing the 3D dose distribution delivered to the moving phantom to be reconstructed. Treatments were planned using the recommended margins for one and three fiducial markers and XLTS 2-view, 1-view and 0-view target-tracking modalities. The dose delivery accuracy was analysed by comparing the reconstructed dose distributions to the planned dose distributions using gamma index analysis. RESULTS: For the 3%/2 mm gamma criterion, gamma passing rates up to 99.37% were observed for the static deliveries. The 3-fiducial and 1-fiducial-based deliveries exhibited passing rates of 93.74% and 97.82%, respectively, in the absence of target rotation. When target rotation was considered, the passing rate for 1-fiducial tracking degraded to 91.24%. The passing rates observed for XLTS 2-view, 1-view and 0-view target-tracking were 92.78%, 96.22% and 76.08%, respectively. CONCLUSIONS: Except for the XLTS 0-view, the dosimetric accuracy of the XLTS was comparable to the FTTS under equivalent treatment conditions. This study gives us further confidence in the CyberKnife XLTS and FTTS systems.

Conus Medullaris Infarction in a Patient With Familial Mediterranean Fever: A Case Report.

BACKGROUND: Spontaneous spinal cord infarctions are rare, especially in the conus medullaris (CM). They are a particularly uncommon presentation in patients with familial Mediterranean fever (FMF). CASE DESCRIPTION: Our patient is a 50-year-old man with FMF, controlled with colchicine for 20 years, who presented to the emergency department when he developed the inability to ambulate without assistance. He also had bowel and bladder incontinence after experiencing burning in his thighs, scrotum, and penis that radiated down his legs. A magnetic resonance imaging scan with and without gadolinium showed T2 hyperintensity changes in the CM and L2 vertebral body, with enhancement of the CM and cauda equina. The patient received high-dose steroids while hospitalized without clinical benefit. He noted improved strength over the past several months, particularly in his left leg, but has persistent sensory disturbances in his buttocks, scrotum, and plantar surfaces. He continues to experience bowel and bladder incontinence. CONCLUSION: Although CM infarction is rare in patients with FMF, it should be considered in the differential diagnosis when there is a high index of suspicion. The presence of vertebral body infarction with T2 changes on magnetic resonance imaging will indicate similar pathology in the CM.

Automatic segmentation of male pelvic anatomy on computed tomography images: a comparison with multiple observers in the context of a multicentre clinical trial.

BACKGROUND: This study investigates the variation in segmentation of several pelvic anatomical structures on computed tomography (CT) between multiple observers and a commercial automatic segmentation method, in the context of quality assurance and evaluation during a multicentre clinical trial. METHODS: CT scans of two prostate cancer patients ('benchmarking cases'), one high risk (HR) and one intermediate risk (IR), were sent to multiple radiotherapy centres for segmentation of prostate, rectum and bladder structures according to the TROG 03.04 "RADAR" trial protocol definitions. The same structures were automatically segmented using iPlan software for the same two patients, allowing structures defined by automatic segmentation to be quantitatively compared with those defined by multiple observers. A sample of twenty trial patient datasets were also used to automatically generate anatomical structures for quantitative comparison with structures defined by individual observers for the same datasets. RESULTS: There was considerable agreement amongst all observers and automatic segmentation of the benchmarking cases for bladder (mean spatial variations < 0.4 cm across the majority of image slices). Although there was some variation in interpretation of the superior-inferior (cranio-caudal) extent of rectum, human-observer contours were typically within a mean 0.6 cm of automatically-defined contours. Prostate structures were more consistent for the HR case than the IR case with all human observers segmenting a prostate with considerably more volume (mean +113.3%) than that automatically segmented. Similar results were seen across the twenty sample datasets, with disagreement between iPlan and observers dominant at the prostatic apex and superior part of the rectum, which is consistent with observations made during quality assurance reviews during the trial. CONCLUSIONS: This study has demonstrated quantitative analysis for comparison of multi-observer segmentation studies. For automatic segmentation algorithms based on image-registration as in iPlan, it is apparent that agreement between observer and automatic segmentation will be a function of patient-specific image characteristics, particularly for anatomy with poor contrast definition. For this reason, it is suggested that automatic registration based on transformation of a single reference dataset adds a significant systematic bias to the resulting volumes and their use in the context of a multicentre trial should be carefully considered.

Retroperitoneal seminoma with 'burned out' phenomenon in the testis.

The rare 'burned out' phenomenon in germ cell tumors is known as the presence of an extragonadal germ cell tumor without traces of neoplasm in the testis. This condition is different and less common from the primary extragonadal germ cell malignancies. These malignancies are treated surgically with or without adjuvant chemotherapy or radiotherapy and their prognosis is better than that of other types of primary extragonadal tumors.