Evaluation of the frequency of tentorial hypoplasia and accompanying gyral herniation using MRI.

Purpose The cerebellar tentorium, the second-largest dural reflection in the brain, separates supratentorial and infratentorial structures. This study aimed to determine the frequency of tentorial hypoplasia (TH) and gyral herniation and their relationship with clinical findings. Methods The standard brain MRIs were examined retrospectively. The presence of TH and laterality were investigated. If hypoplasia was accompanied by a gyrus extending inferior to the line where the tentorium should be located, this was recorded as tentorial hypoplasia-herniated gyrus (TH-HG), while the cases with hypoplasia alone were noted as isolated TH. It was also determined which gyrus or gyri were herniated. The clinical findings of the patients were obtained, and the correlation between HG was explored. Results Standard brain MRIs of the 2051 patients were evaluated. Two hundred ten patients were excluded from the study due to different intracranial disorders, and 1841 patients, 739 (40.1%) males, and 1102 (59.9%) females, were included. Isolated TH or TH-HG was present in 56 patients, resulting in a prevalence of 3.04%. Of the patients with TH or TH-HG, 15 were men, and 41 were women. TH and TH-HG were significantly more common in women (p=0.038). TH-HG was unilateral in 22 (39.2%) patients and bilateral in 21 (37.5%). Left TH was found in 11 (19.6%) patients, left TH-HG in 29 (51.7%), right TH in eight (14.2%), and left TH-HG in 35 (62.5%). Conclusion Hypoplasia of the tentorium is a rare and unknown anomaly that can be easily diagnosed using MRI, and different gyral herniations may accompany TH.

An extrahepatic hydatid cyst with the fat-fluid level.

A hydatic cyst is a zoonosis caused by the larva of a tapeworm Echinococcus granulosus. The liver is the most commonly affected organ. Soft tissue localization has been reported in 2.3% of cases. Herein, we present a patient with a fat-containing hydatid cyst located in the left thigh. There are only a few reports in the literature on the presence of the fat-fluid level within a hydatid cyst. Previous studies have suggested that fat-containing hydatid cysts occur due to their cysto-biliary communication in the liver. In our case, we describe a fat-containing hydatid cyst in the extrahepatic location and discuss the pathophysiologic mechanism of fat inside it.

Absence of CSF flow within the cerebral aqueduct in spontaneous intracranial hypotension: a report of two cases.

Spontaneous intracranial hypotension (SIH) is a potentially debilitating condition resulting from a low cerebrospinal fluid (CSF) volume secondary to spinal CSF leakage. Characteristic clinical and radiological imaging findings are helpful in diagnosis. Herein, we present and discuss the magnetic resonance imaging (MRI) and CSF flow study of two patients with SIH and no CSF flow within the cerebral aqueduct, which is extremely rare in the literature.

Mass and non-mass breast MRI patterns: a radiologic approach to sick lobe theory.

BACKGROUND: According to sick lobe theory, one or more lobes of the breast are more prone to the development of carcinoma. However, the implications of this theory in breast magnetic resonance imaging (MRI) are unknown. PURPOSE: To evaluate the MRI appearance of mass type (multifocal and multicentric diseases) and non-mass type (non-mass enhancements) sick lobe patterns, together with the histopathology results. MATERIAL AND METHODS: MRI reports of 2015 patients in two tertiary breast imaging centers between June 2012 and June 2018 were retrospectively reviewed for multifocal-multicentric diseases and segmental, linear, and regional enhancements. A total of 113 patients were included. The specimens obtained by thick needle, vacuum, excisional biopsy/lumpectomy or mastectomy after breast MRI scans were pathologically assessed. The pathologic results were categorized as invasive carcinoma, precursor, and benign proliferative lesions according to the 2012 World Health Organization Classification of Tumors. RESULTS: The percentage of underlying benign and precursor invasive lesions was significantly different in patients with mass and non-mass MRI patterns. While the pathology results of mass type patterns were premalignant and malignant in all cases, nearly half of the underlying histologies were benign proliferative subtypes in patients with non-mass type patterns. CONCLUSION: In this study, the mass and non-mass patterns derived from sick lobe theory were related to different risks of malignancy in the pathological examinations.

An unusual phenotype of radial longitudinal deficiency (radial hemimelia) presenting in a young adult male.

Radial longitudinal deficiency is a rare skeletal anomaly characterized by a defect in the development of structures that form the radial half of the forearm. The disorder is associated with a large spectrum of preaxial abnormalities. It is shown that the thumb and preaxial carpal bones are almost always hypoplastic or absent in almost all types of radial longitudinal deficiency. Congenital dislocation of the dysplastic radial head may accompany this rare deformity. Herein, we present a 20-year-old male patient with radial longitudinal deficiency who had a markedly hypoplastic radius but had a thumb and carpal bones with normal size, shape, and joint relations. Further, the right radial longitudinal deficiency of our patient was unusually accompanied by left congenital radial head dislocation. Our case shows that, although rare, radial longitudinal deficiency can present without any carpal and thumb abnormalities. And the current case also shows that a contralateral sided congenital radial head dislocation may accompany radial longitudinal deficiency.

Local and systemic factors associated with marginal bone loss around dental implants: a retrospective clinical study.

OBJECTIVES: The aim of this study was to determine the influence of patient-related systemic factors, local bone and intraoral factors, and implant-related factors on peri-implant marginal bone loss (MBL). METHOD AND MATERIALS: The following data were collected from patients who received dental implants and were recalled for examinations at least 3 years after treatment completion: medical history, age, sex, habits, periodontal health, implant size and surface, surgical procedure, prosthesis type, implant failure, Plaque Index, and oral hygiene. MBL was investigated using both baseline and follow-up panoramic radiographs. RESULTS: The study included 1,126 dental implants placed in 304 patients (185 [60.9%] women and 119 [39.1%] men). The mean age was 54.30 ± 13.52 years (range 22 to 83 years). The mean follow-up period was 58.8 ± 11.2 months. The MBL was observed in 271 (24.1%) implants, of which 160 (14.2%) were ≤ 2 mm and 111 (9.9%) were > 2 mm. Respective mean MBL values on mesial and distal sides were 0.42 ± 1.03 mm and 0.42 ± 1.02 mm. Of the implants, 19 (1.7%) were lost, leading to an implant success rate of 98.3%. Age, history of hysterectomy, history of periodontitis, oral hygiene, abrasions, smoking, implant location, implant surface, implant length, surgical procedure type, and prosthesis type were all found to be statistically significant for MBL (P < .05). Certain combinations of these factors resulted in increased MBL. CONCLUSION: In the present study, local factors had more significant effects on MBL than did systemic factors, and combinations of these factors had greater effects on MBL.