Stability and sensitivity of water T2 obtained with IDEAL-CPMG in healthy and fat-infiltrated skeletal muscle.

Quantifying muscle water T2 (T2 -water) independently of intramuscular fat content is essential in establishing T2 -water as an outcome measure for imminent new therapy trials in neuromuscular diseases. IDEAL-CPMG combines chemical shift fat-water separation with T2 relaxometry to obtain such a measure. Here we evaluate the reproducibility and B1 sensitivity of IDEAL-CPMG T2 -water and fat fraction (f.f.) values in healthy subjects, and demonstrate the potential of the method to quantify T2 -water variation in diseased muscle displaying varying degrees of fatty infiltration. The calf muscles of 11 healthy individuals (40.5 ± 10.2 years) were scanned twice at 3 T with an inter-scan interval of 4 weeks using IDEAL-CPMG, and 12 patients with hypokalemic periodic paralysis (HypoPP) (42.3 ± 11.5 years) were also imaged. An exponential was fitted to the signal decay of the separated water and fat components to determine T2 -water and the fat signal amplitude muscle regions manually segmented. Overall mean calf-level muscle T2 -water in healthy subjects was 31.2 ± 2.0 ms, without significant inter-muscle differences (p = 0.37). Inter-subject and inter-scan coefficients of variation were 5.7% and 3.2% respectively for T2 -water and 41.1% and 15.4% for f.f. Bland-Altman mean bias and ±95% coefficients of repeatability were for T2 -water (0.15, -2.65, 2.95) ms and f.f. (-0.02, -1.99, 2.03)%. There was no relationship between T2 -water (ρ = 0.16, p = 0.07) or f.f. (ρ = 0.03, p = 0.7761) and B1 error or any correlation between T2 -water and f.f. in the healthy subjects (ρ = 0.07, p = 0.40). In HypoPP there was a measurable relationship between T2 -water and f.f. (ρ = 0.59, p < 0.001). IDEAL-CPMG provides a feasible way to quantify T2 -water in muscle that is reproducible and sensitive to meaningful physiological changes without post hoc modeling of the fat contribution. In patients, IDEAL-CPMG measured elevations in T2 -water and f.f. while showing a weak relationship between these parameters, thus showing promise as a practical means of quantifying muscle water in patient populations.

Primary Calvarial Lymphoma: A Case Report.

Calvarial lymphoma is radiologically similar in many respects to meningiomas, solid fibrous tumours, osteomyelitis, and metastatic carcinomas. Even though it is an extremely rare phenomenon, the initial suspicion and detection of calvarial lymphoma are paramount to establishing a correct diagnosis which helps to determine an appropriate management strategy. We present an illustrative rare case of primary calvarial lymphoma along with a literature review focusing on the best management strategy for this rare entity. A 45-year-old female presented to our center in March 2022. She had a history of forehead swelling, which was progressively increasing in size over time. The metastatic workup and bone marrow biopsy were negative. Initially, extensive surgery was planned to resect the lesion, but after a discussion with the multidisciplinary team, a biopsy of the lesion was taken, which revealed a large B-cell lymphoma. It is prudent to consider calvarial lymphoma in the differential diagnosis of a progressively growing skull lesion, which may obviate the need for large resective surgery. A biopsy plus chemoradiation may be all that is required.

Dermoid Cyst in the Posterior Fossa Associated With Dermal Sinus and Abscess Formation: A Case Report.

Posterior fossa dermoid cysts are rare intracranial tumors. Most are congenital and develop during early pregnancy but manifest later in life. We report a case of a congenital posterior fossa dermoid cyst in a 22-year-old patient presenting with fever and multiple neurological complaints. Imaging studies revealed a bony defect in the occipital bone suggestive of sinus formation, heterogeneous hypointensity on T1-weighted image (T1WI), and post-contrast peripheral enhancement suggestive of an infectious process and abscess formation. The histopathological examination was typical for a dermoid cyst containing adnexal structures. This report reviews the case with its unique location and unusual radiological features. Further, the clinical presentation, diagnosis modalities, and treatment outcomes are discussed.

Posterior Reversible Encephalopathy Syndrome Following Intracranial Hypotension Due to Cerebrospinal Fluid (CSF) Leakage: A Report of Two Cases.

Posterior reversible encephalopathy syndrome (PRES) in cases of intracranial hypotension is a life-threatening condition. Early suspicion, appropriate treatment, and tight control of possible contributing factors that may facilitate PRES in cerebrospinal fluid (CSF) leak patients may bring a more favorable outcome, lowering the morbidity and mortality rate. Two cases of PRES with features of intracranial hypotension are presented. We also discussed the possible pathogenesis of PRES in patients with intracranial hypotension. We emphasize the importance of the early diagnosis and treatment of ICH by repairing the leakage and further prompt attention to tight blood pressure control in those patients to avoid PRES development.

Pneumocephalus resulting from chest infection complicated by pleural-subarachnoid fistula.

Pleural-subarachnoid fistula is a rare type of Cerebrospinal fluid fistula with less than 60 cases reported in the literature. Here we present a case of 55-year-old female patient, known case of acute myeloid leukemia on chemotherapy, who developed pleural-subarachnoid fistula due to invasive atypical apical lung fungal infection. All of the reported cases in the literature were secondary to trauma or post-surgery. To our knowledge, this is the first reported case of pleural-subarachnoid fistula developed as sequela of fungal infection.

Atypical haemorrhagic colloid cyst: 2 case reports surgical management and review of literature.

INTRODUCTION: Colloid cysts are benign cystic lesions located at the anterior part of the third ventricle mostly at the foramen of Monro and contain colloid material. Hemorrhage in a colloid cyst is exceedingly rare. Only 15 clinically diagnosed cases of haemorrhagic cysts were reported in the literature and 5 more cases on autopsy. Here we report two rare cases of a haemorrhagic colloid cyst describing the atypical radiological findings, the undertaken surgical procedures and histopathological results. PRESENTATION OF CASES: We presented 2 cases of haemorrhagic third ventricle colloid cysts. First case is a 27-year-old male patient, presented with dizziness, nausea, vomiting and blurring of vision. He was operated by transcortical endoscopic transventricular excision of a third ventricular cyst and the insertion of external ventricular drain. The second patient is a 21-year-old male, presented with history of worsening headache for 1 month associated with blurring of vision. The patient had a transcortical microscopic, transventricular cyst excision. DISCUSSION: Many questions regarding the best way to diagnose and manage such lesions remain unanswered. Hence, we summarize the relevant diagnostic images and best surgical techniques. CONCLUSION: We concluded that, though exceedingly rare, colloid cyst can bleed and cause rapid deterioration in neurological status, thus, presence of atypical features should alert the physicians to consider atypical colloid cyst that would be valuable in surgical decision making whether endoscopic or microscopic.

A rare case of Erdheim-Chester disease in the breast.

Erdheim-Chester disease (ECD) is rare non-Langerhans histiocytosis with distinctive radiologic and pathologic entities. We report a rare case of which ECD was involving the breast with only eight similar cases reported in the English literature. Our patient was a 52-year-old female patient with ECD involving the breast, mesentery, left kidney, retroperitoneum and the skeleton. The diagnosis was based on distinctive imaging and histopathological findings. The patient received a new novel treatment as part of a clinical trial in the United States and showed clinical and radiological improvement. SIMILAR CASES PUBLISHED: 8

Prognostic value of mammographic breast density in patients with metastatic breast cancer.

Breast density is a modifiable trait linked with breast cancer predisposition. However, the relation between mammographic breast density and survival outcome is not yet clarified. The present study aims to study the prognostic value of mammographic density in patients diagnosed with metastatic breast cancer. In this observational study, breast cancer patients with metastatic disease at diagnosis were enrolled. Two-view mammograms were performed at diagnosis, and breast density was quantitatively assessed. Progression-free survival (PFS) was correlated with breast density and other prognostic variables in univariate and multivariate analyses. PFS, stratified by different prognostic factors, was assessed in low compared to high density patients to check for possible differential survival outcome in patients' subgroups. Among the sixty enrolled patients, median PFS in low density patients was significantly better than those with high density (18.4 months, 95 % CI 14.88-22.15 vs. 9.3 months, 95 % CI 8.51-13.60, respectively, p = 0.002). Significant correlation of breast density with PFS persisted after adjustment by body mass index (p = 0.003) and after multivariate analysis incorporating other prognostic variables (HR 6.16, 95 % CI (2.17-17.48), p = 0.001). PFS was better in low density patients older than 40 years at diagnosis (p = 0.001), with HER2-negative disease (p = 0.015), hormonal receptor-positive phenotype (p = 0.020), patients with single site of metastasis (p = 0.006), and patients with bone-only metastases (p = 0.042). Breast density assessed at the time of diagnosis was significantly correlated with PFS of metastatic breast cancer patients. Survival outcome is improved in certain patients' subgroups with low breast density.