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41.
According to the eighth edition of the AJCC Cancer Staging Manual (AJCC8), a depth of invasion (DOI) >10 mm is classified as pT3, representing a locally advanced tumour requiring postoperative radiotherapy (PORT). When node-negative, however, evidence regarding whether PORT improves loco-regional control or survival is unclear. To clarify this, two cohorts of patients were studied: (1) patients classified as pT3N0 by the seventh edition of the AJCC manual (AJCC7), with DOI >10 mm and a tumour diameter >4 cm (17 patients who received PORT), and (2) patients classified as pT1N0 and pT2N0 by AJCC7, with DOI >10 mm and a tumour diameter <4 cm (55 patients who did not receive PORT). Loco-regional control and survival were analysed. PORT was found not to impact overall survival or disease-free survival. It was also found not to impact local, regional, or distant recurrence. Although the two subsets of patients considered here (DOI >10 mm with tumour diameter below or above 4 cm) were previously distinct, they are both considered pT3 in AJCC8. Data from this study indicate that the routine administration of PORT to patients with a DOI >10 mm may not be warranted in the absence of other risk features such as nodal disease or close margins.  相似文献   
42.
43.
The kidneys in paroxysmal nocturnal hemoglobinuria   总被引:6,自引:0,他引:6  
Long-term study of 21 PNH patients revealed an unexpectedly high incidence of functional and anatomic renal abnormalities. Most patients demonstrated varying degrees of hematuria and proteinuria distinct from hemoglobinuria. Evaluation of renal function revealed hyposthenuria, abnormal tubular function, and declining creatinine clearance. Radiologically these patients had enlarged kidneys, cortical infarcts, cortical thinning, and papillary necrosis which were confirmed by autopsy studies. Hypertension developed in eight patients. Urinary tract infection was uncommon. The renal findings bear striking similarity to those of sickle cell anemia. Contrary to the usual opinion, out studies clearly showed evidence of widespread renal pathology in PNH most likely due to repeated microvascular thrombosis similar to the venous thrombosis involving other organs in this disorder.  相似文献   
44.
Pyoderma gangrenosum(PG) is a rare ulcerating inflammatory neutrophilic dermatosis. Genital involvement has been rarely reported. We report such a case of 24- year- old, male patient living with HIV/AIDS(PLHIV) who presented with progressive genital ulceration, not responding to oral antibiotics and aciclovir, gradually increasing in size over 15-18 months. Repeated biopsies showed acute on chronic inflammation. The lesion partially responded to oral and topical corticosteroids but soon increased in size after tapering the dosage of the steroids.Then patient was given Imiquimod 5% cream to be applied over the lesion once daily for 2-4 weeks. Lesion cleared completely in 4 weeks and is in remission since last 6 months. The case report highlights the successful use of topical Imiquimod 5% cream in the treatment of penile PG.  相似文献   
45.

Introduction

The rotating hinge prosthesis was originally used and designed as a primary total knee arthroplasty implant, but was hampered due to poor outcomes and catastrophic failures. Newer rotating hinge implants can be utilized in complex revision total knee arthroplasties when appropriately indicated, but their outcome data is very difficult to interpret due to the strict and varied indications for use and subsequently small number of procedures performed. The goal of this review is to evaluate the current evidence on large cohort, rotating hinge knee prostheses used in the revision setting, in order to provide a clearer understanding of the indications, outcomes and complications.

Methods

The PubMed database was utilized to search the available literature regarding “hinged knee,” or “rotating hinge” devices. Exclusion criteria included papers focusing on primary arthroplasty, revision for oncologic issues, one-stage revision for infection or studies with less than fifty cases.

Results

Review of 115 abstracts after initial search, led to ten studies in the literature that met our inclusion and exclusion criteria. The data shows that rotating hinge knee implants have good survivorship ranging from 51% to 92.5% at 10 years post-operatively. Complication rates range from 9.2% to 63% with infection and aseptic loosening as the most common complications.

Conclusion

Rotating hinge knee prostheses are most commonly indicated for infection, aseptic loosening, instability and bone loss in the literature. They have good outcome scores and survivorship, but continue to have high complication and revision rates. The implant is a good option when utilized appropriately for patients that are not candidates for less constrained devices.  相似文献   
46.
Magnetic resonance (MR) images of the brain in 285 patients between the ages of 2 and 25 years were retrospectively studied to determine the appearance of brain iron accumulation. The globus pallidus, red nucleus, substantia nigra, and dentate nucleus were evaluated with long TR/TE (repetition time/echo time) spin-echo sequences and staged. All four regions in most patients were initially hyperintense compared with white matter (stage I) before becoming isointense (stage II) and subsequently hypointense (stage III). The globus pallidus was the first to reach stage III, the red nucleus and substantia nigra were next, and the dentate nucleus was last. In general, decreased signal intensity (stage III) was not seen in these regions in patients less than 10 years old; in most patients it was seen by age 25 years. The dentate nucleus decreased in signal intensity more slowly and inconsistently; only one-third of patients had reached stage III by age 25 years. The temporal sequence of normal iron deposition as detected with MR imaging is helpful not only in the diagnosis of known iron-deposition diseases but also in the detection of iron-related pathologic changes.  相似文献   
47.
Osteomyelitis: detection with US   总被引:2,自引:0,他引:2  
Abiri  MM; Kirpekar  M; Ablow  RC 《Radiology》1989,172(2):509-511
To evaluate the role of ultrasound (US) in the detection of osteomyelitis, the authors prospectively studied 48 patients clinically suspected of having osteomyelitis. A sonographic diagnosis was made if fluid was seen directly in contact with bone, without intervening soft tissues. Twelve of the 48 patients were subsequently found to have osteomyelitis. In 10 of them, US demonstrated abnormal fluid adjacent to the bone. This fluid was thought to represent an inflammatory exudate dissecting in a subperiosteal and/or extraperiosteal location. Eight of the 48 patients had soft-tissue fluid collections. The rest of the patients either had no abnormalities or had cellulitis. The authors conclude that US can be useful in the detection of osteomyelitis.  相似文献   
48.
The effects of a paramagnetic contrast agent, gadolinium-DTPA (Gd-DTPA), on magnetic resonance (MR) imaging of acute cerebral ischemia was investigated in a feline model of middle cerebral artery occlusion. Imaging was performed both before and after administration of an intravenous dose of 0.2 mmol/kg of Gd-DTPA. The animals were then sacrificed for pathologic correlation. No changes in intensity or relaxation times were noted before or after Gd-DTPA administration in two animals with 2 hours of occlusion. Infarcts were noted before and after contrast enhancement in all six cats with ischemia of greater than 16-hours duration. Gd-DTPA caused significant increase in intensity of infarct but not in that of normal cerebral tissue. Rapid enhancement was visible in infarcts of 16-24 hours, but such enhancement was slower in infarcts of 72-168 hours, presumably owing to slowed inflow caused by increased vasogenic edema in the latter group. Contrast enhancement of acute cerebral ischemic lesions with Gd-DTPA offers no improvement in sensitivity of MR imaging, although the conspicuity of the lesion may be improved. Additionally, contrast media may provide potential temporal and pathophysiological data for better characterization of cerebral ischemia.  相似文献   
49.
Ectopic ureter and ureterocele: their varied sonographic manifestations   总被引:1,自引:0,他引:1  
The sonographic examinations of four patients with simple ectopic ureters and 11 with ectopic ureteroceles were reviewed to determine distinguishing characteristics. Ectopic ureters, in cases of extreme dilatation and tortuosity, sometimes mimic multiseptated, cystic abdominal masses. However, the proximal portions of some severely dilated ureters are surprisingly small. Ectopic ureters sometimes indent the lower vesical wall, simulating a ureterocele. Ectopic ureteroceles are dynamic structures, changing in shape and size according to intravesical pressure. The lower pole of a duplex kidney may be difficult to detect because of displacement by the dilated upper renal pelvis and ureter. The renal parenchyma associated with an ectopic ureter may be equally difficult or impossible to find because of diminutive dysplasia or, less commonly, acquired atrophy. Dysplasia is characterized sonographically by highly echogenic parenchyma, lack of corticomedullary differentiation, and occasionally massive enlargement by cysts. Ectopic ureters and ureteroceles can be identified by fetal sonography.  相似文献   
50.
Primary retroperitoneal teratoma is a rare entity in adults. It has a distinctive imaging appearance. We describe a case of a 22-year-old patient who was referred to our hospital with the complaint of abdominal distension. Radiological work-up disclosed a retroperitoneal teratoma. Laparotomy with tumour resection was performed. Pathological examination revealed a benign cystic teratoma. The patient is doing well at follow-up.  相似文献   
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