Imaging features of the postoperative spine: a guide to basic understanding of spine surgical procedures.

Spinal surgical procedures are becoming more common over the years, and imaging studies can be requested in the postoperative setting, such as a baseline study when implants are used, or when there is a new postoperative issue reported by the patient or even as routine surveillance. Therefore, it helps the surgeon in the appropriate management of cases. In this context, there is increasing importance of the radiologist in the adequate interpretation of postoperative images, as well as in the choice of the most appropriate modality for each case, especially among radiographs, computed tomography, magnetic resonance imaging and nuclear medicine. It is essential to be familiar with the main types of surgical techniques and imaging characteristics of each one, including the type and correct positioning of hardware involved, to differentiate normal and abnormal postoperative appearances. The purpose of this pictorial essay is to illustrate and discuss the more frequently used spine surgical interventions and their imaging characteristics, with an emphasis on classical decompression and fusion/stabilization procedures. KEY POINTS: Plain radiographs remain the main modality for baseline, dynamic evaluation, and follow-ups. CT is the method of choice for assessing bone fusion, hardware integrity and loosening. MRI should be used to evaluate bone marrow and soft tissue complications. Radiologists should be familiar with most performed spinal procedures in order to differentiate normal and abnormal. CRITICAL RELEVANCE STATEMENT: This article discusses the main surgical procedures involved in the spine, which can be didactically divided into decompression, stabilization-fusion, and miscellaneous, as well as the role of diagnostic imaging methods and their main findings in this context.

Spontaneous intracranial hypotension and its complications.

Spontaneous intracranial hypotension (SIH) is a syndrome that was unknown until the advent of magnetic resonance imaging (MRI). It is a cause of orthostatic headache, which remains underdiagnosed and, rarely, can result in several complications including dural venous sinus thrombosis, subdural hematoma and subarachnoid hemorrhage. Some of these complications are potentially life-threatening and should be recognized promptly, mainly by imaging studies. We reviewed the MRI of nine patients with SIH and describe the complications observed in three of these patients. Two of them had subdural hematoma and one had a dural venous sinus thrombosis detected by computed tomography and MRI. We concluded that MRI findings are of great importance in the diagnosis of SIH and its complications, which often influence the clinical-surgical treatment of the patient.

Spontaneous intracranial hypotension and its complications / Hipotensão intracraniana espontânea e complicações

ABSTRACT Spontaneous intracranial hypotension (SIH) is a syndrome that was unknown until the advent of magnetic resonance imaging (MRI). It is a cause of orthostatic headache, which remains underdiagnosed and, rarely, can result in several complications including dural venous sinus thrombosis, subdural hematoma and subarachnoid hemorrhage. Some of these complications are potentially life-threatening and should be recognized promptly, mainly by imaging studies. We reviewed the MRI of nine patients with SIH and describe the complications observed in three of these patients. Two of them had subdural hematoma and one had a dural venous sinus thrombosis detected by computed tomography and MRI. We concluded that MRI findings are of great importance in the diagnosis of SIH and its complications, which often influence the clinical-surgical treatment of the patient.

RESUMO Hipotensão Intracraniana Espontânea (HIE) é uma síndrome desconhecida até o advento das imagens de Ressonância Magnética (RM). É uma causa de cefaleia ortostática que permanece subdiagnosticada e raramente resulta em complicações, como trombose de seios venosos durais, hematoma subdural e hemorragia subaracnoidea. Algumas dessas complicações são potencialmente ameaçadoras à vida e devem ser prontamente reconhecidas pelos estudos de imagem. Nós revisamos as RM de 9 pacientes com HIE e descrevemos as complicações observadas em 3 casos. Dois deles tiveram hematoma subdural e um teve trombose de seio venoso dural detectados por tomografia computadorizada e RM. Concluímos que achados de RM são de grande importância no diagnóstico de HIE e suas complicações, frequentemente influenciando o tratamento clínico-cirúrgico do paciente.

Risk factors for intensive care unit admission in patients with severe leptospirosis: a comparative study according to patients' severity.

BACKGROUND: The aim of this study is to investigate predictive factors for intensive care unit (ICU) admission among patients with severe leptospirosis. METHODS: This is a retrospective study with all patients with severe leptospirosis admitted to a tertiary hospital. Patients were divided in ICU and ward groups. Demographical, clinical and laboratory data of the groups were compared as well as acute kidney injury (AKI) severity, according to the RIFLE criteria (R = Risk, I = Injury, F = Failure, L = Loss, E = End-stage kidney disease). RESULTS: A total of 206 patients were included, 83 admitted to ICU and 123 to ward. Mean age was 36 ± 15.8 years, with 85.9% males. Patients in ICU group were older (38.8 ± 15.7 vs. 34.16 ± 15.9 years, p = 0.037), had a shorter hospital stay (4.13 ± 3.1 vs. 9.5 ± 5.2 days, p = 0.0001), lower levels of hematocrit (29.6 ± 6.4 vs. 33.1 ± 8.6%, p = 0.003), hemoglobin (10.2 ± 2.4 vs. 11.6 ± 1.9 g/dL, p < 0.0001), and platelets (94,427 ± 86,743 vs. 128,896 ± 137,017/mm(3), p = 0.035), as well as higher levels of bilirubin (15.0 ± 12.2 vs. 8.6 ± 9.5 mg/dL, p = 0.001). ICU group also had a higher frequency of severe AKI (RIFLE-"Failure": 73.2% vs. 54.2%, p < 0.0001) and a higher prevalence of dialysis requirement (57.3% vs. 27.6%, p < 0.0001). Mortality was higher among ICU patients (23.5% vs. 5.7%, p < 0.0001). Independent predictors for ICU admission were tachypnea (p = 0.027, OR = 13, CI = 1.3-132), hypotension (p = 0.009, OR = 5.27, CI = 1.5-18) and AKI (p = 0.029, OR = 14, CI = 1.3-150). Ceftriaxone use was a protective factor (p = 0.001, OR = 0.13, CI = 0.04-0.4). CONCLUSIONS: Independent risk factors for ICU admission in leptospirosis include tachypnea, hypotension and AKI. Ceftriaxone was a protective factor for ICU admission, suggesting that its use may prevent severe forms of the disease.