Validación de la resonancia magnética pélvica como método de elección para determinar la distancia al margen anal en el cáncer de recto / Validation of pelvic magnetic resonance imaging as the method of choice to determine the distance to the anal margin in rectal cancer

Introducción: La altura exacta del tumor en el recto y sus relaciones anatómicas contribuyen a determinar la estrategia terapéutica multidisciplinar basada en la combinación de radio-quimioterapia y cirugía radical. Nuestro objetivo es valorar cuál es el método diagnóstico más preciso en la medición preoperatoria de la distancia al margen anal, y si la resonancia magnética pélvica (RM) puede sustituir a los métodos instrumentales clásicos. Métodos: Estudio prospectivo de precisión diagnóstica entre colonoscopia (CF), rectoscopia rígida (RRp) y RM en pacientes con indicación de cirugía radical. La RRp intraoperatoria fue considerada la prueba de referencia. Se analizaron las correlaciones entre las distintas técnicas y su coeficiente de determinación, así como el coeficiente de correlación intraclase y el grado de acuerdo entre los distintos test. Resultados: Se incluyeron 96 pacientes con edad media (DE) de 68 (14,1) años y predominio de varones (65%). Un 72% recibió tratamiento neoadyuvante. La distancia media al margen anal, medida mediante CF=103,5mm, fue significativamente mayor al resto, que obtuvieron valores similares: RRp=81,1, RM=77,4, RRp intraoperatoria=82,9mm (p<0,001). Se objetivó una significativa correlación intraclase y hubo un elevado acuerdo entre todas las mediciones pre e intraoperatorias a excepción de la realizada mediante CF, que sobreestimó el resultado. La RM aportó información más individualizada y precisa. Conclusiones: Existe variabilidad entre los métodos de medición, siendo la colonoscopia el menos fiable. La RM ofrece valores objetivos, comparables, precisos e individualizados que pueden sustituir a los obtenidos por RR en tumores de cualquier localización del recto. (AU)

Introduction: Distance from anal verge of rectal tumors and their anatomical relationships contribute to determine the multidisciplinary therapeutic strategy based on the combination of radio-chemotherapy and radical surgery. Our aims are to investigate which is the most accurate method for the preoperative measuring of the distance from the anal verge in rectal tumors and if the pelvic MRI can substitute the classical instrumental methods. Methods: Prospective study of diagnostic precision between flexible colonoscopy (FC), preoperative rigid rectosigmoidoscopy (pRR) and pelvic MRI in patients scheduled to radical surgery. Rigid intraoperative rectoscopy (iRR) was considered the reference test. The correlations between the different techniques and their determination coefficient as well as the intraclass correlation coefficient and the degree of agreement between the different tests were analyzed. Results: 96 patients (65% males), mean age (SD): 68 (14.1) years were included. 72% received neoadjuvant treatment. The mean distance to the anal margin measured by FC=103.5mm, was significantly greater than others, which had similar values: pRR=81.1; MRI=77.4; iRR=82.9mm (P<.001). A significant intraclass correlation was observed and there was high agreement between all pre- and intraoperative measurements except for the performed by FC, which overestimated the results. MRI provided more individualized and accurate information. Conclusions: There is variability between the measurement methods, being colonoscopy the least reliable. MRI offers objective, comparable, accurate and individualized values that can replace those obtained by pRR for tumors of any location in the rectum. (AU)

Validation of pelvic magnetic resonance imaging as the method of choice to determine the distance to the anal margin in rectal cancer.

INTRODUCTION: Distance from anal verge of rectal tumours and their anatomical relationships contribute to determine the multidisciplinary therapeutic strategy based on the combination of radio-chemotherapy and radical surgery. Our aims are to investigate which is the most accurate method for the preoperative measuring of the distance from the anal verge in rectal tumours and if the pelvic MRI can substitute the classical instrumental methods. METHODS: Prospective study of diagnostic precision between flexible colonoscopy (FC), preoperative rigid rectosigmoidoscopy (pRR) and pelvic MRI in patients scheduled to radical surgery. Rigid intraoperative rectoscopy (iRR) was considered the reference test. The correlations between the different techniques and their determination coefficient as well as the intraclass correlation coefficient and the degree of agreement between the different tests were analyzed. RESULTS: 96 patients (65% males), mean age (SD): 68 (14.1) years were included. 72% received neoadjuvant treatment. The mean distance to the anal margin measured by FC = 103.5 mm, was significantly greater than others, which had similar values: pRR = 81.1; MRI = 77.4; iRR = 82.9 mm (P < .001). A significant intraclass correlation was observed and there was high agreement between all pre- and intraoperative measurements except for the performed by FC, which overestimated the results. MRI provided more individualized and accurate information. CONCLUSIONS: There is variability between the measurement methods, being colonoscopy the least reliable. MRI offers objective, comparable, accurate and individualized values that can replace those obtained by pRR for tumours of any location in the rectum.

Validation of pelvic magnetic resonance imaging as the method of choice to determine the distance to the anal margin in rectal cancer. / Validación de la resonancia magnética pélvica como método de elección para determinar la distancia al margen anal en el cáncer de recto.

INTRODUCTION: Distance from anal verge of rectal tumors and their anatomical relationships contribute to determine the multidisciplinary therapeutic strategy based on the combination of radio-chemotherapy and radical surgery. Our aims are to investigate which is the most accurate method for the preoperative measuring of the distance from the anal verge in rectal tumors and if the pelvic MRI can substitute the classical instrumental methods. METHODS: Prospective study of diagnostic precision between flexible colonoscopy (FC), preoperative rigid rectosigmoidoscopy (pRR) and pelvic MRI in patients scheduled to radical surgery. Rigid intraoperative rectoscopy (iRR) was considered the reference test. The correlations between the different techniques and their determination coefficient as well as the intraclass correlation coefficient and the degree of agreement between the different tests were analyzed. RESULTS: 96 patients (65% males), mean age (SD): 68 (14.1) years were included. 72% received neoadjuvant treatment. The mean distance to the anal margin measured by FC=103.5mm, was significantly greater than others, which had similar values: pRR=81.1; MRI=77.4; iRR=82.9mm (P<.001). A significant intraclass correlation was observed and there was high agreement between all pre- and intraoperative measurements except for the performed by FC, which overestimated the results. MRI provided more individualized and accurate information. CONCLUSIONS: There is variability between the measurement methods, being colonoscopy the least reliable. MRI offers objective, comparable, accurate and individualized values that can replace those obtained by pRR for tumors of any location in the rectum.

Computer-tomographic verification of ultrasound-guided piriformis muscle injection: a feasibility study.

BACKGROUND: Approximately 6% to 8% of lumbar pain cases, whether associated with radicular pain or not, may be attributed to the presence of piriformis muscle syndrome. Available treatments, among others, include pharmacotherapy, physical therapy, and injections of different substances into the muscle. Various methods have been used to confirm correct needle placement during these procedures, including electromyography (EMG), fluoroscopy, computed tomography (CT), or magnetic resonance imaging (MRI). Ultrasonography (US) has now become a widely used technique and therefore may be an attractive alternative for needle guidance when injecting this muscle. OBJECTIVE: The objective of this study was to assess the reliability of US in piriformis injection of patients with piriformis syndrome. STUDY DESIGN: Feasibility study; 10 patients with piriformis muscle syndrome were injected with botulinum toxin A using a US-guided procedure. Then patients were administered 2 mL iodinated contrast and were then transferred to the CT scanner, where they underwent pelvic and hip imaging to assess intramuscular distribution of the iodinated contrast. SETTING: Multidisciplinary Pain Management Department in Spain. RESULTS: Of all 10 study patients (8 women, 2 men), 9 had intramuscular or intrafascial contrast distribution. Distribution did not go deeper than the piriformis muscle in any of the patients. The absence of contrast (intravascular injection) was not observed in any case. LIMITATIONS: The main limitation of our study is the use of ionizing radiation as confirmation technique. CONCLUSION: Ultrasound-guided puncture may be a reliable and simple procedure for injection of the piriformis muscle, as long as good education and training are provided to the operator. US has a number of advantages over traditional approaches, including accessibility and especially no ionizing radiation exposure for both health care providers and patients.

Difficulties in distinguishing between an atlas fracture and a congenital posterior atlas arch defect in postmortem analysis.

We found one atlas from a sample of 148 skeletons (0.67%) that presented different anatomical variations which made it difficult to determine whether the vertebra had an atlas fracture, an unusual Type B posterior atlas arch defect, or a combination of both. We carried out a stereomicroscopy, radiographic, and computerized tomography scan study that revealed that the dry atlas we found presented a very uncommon congenital Type B posterior atlas arch defect, simulating a fracture. In short, the present paper has revealed that differentiating Type B posterior atlas arch defects from fractures in post-mortem dry vertebrae is more difficult than expected. Thus we believe that it can be easier than expected to mistake Type B posterior arch defects for fractures and vice versa in postmortem studies.

Análisis de nuestra experiencia mediante el uso de resonancia magnética dinámica pelviana en la evaluación del síndrome de defecación obstructiva / Analysis of experience in the use of dynamic pelvic magnetic resonance imaging in the assessment of obstructive defaecation syndrome

Introducción El diagnóstico etiológico del síndrome de defecación obstructiva (DO) requiere, entre otros, de métodos de imagen El objetivo del presente estudio es analizar y comparar descriptivamente con la exploración clínica los hallazgos de la resonancia magnética pelviana dinámica (RMPD) en pacientes con DO. Material y métodos Se efectúa un estudio prospectivo comparativo entre la exploración física y la RMPD, analizando los resultados de forma descriptiva. Se incluyeron 30 pacientes (2 hombres y 28 mujeres), con una mediana de edad de 60 años (rango 23-76), con sintomatología de DO a los que se efectuó anamnesis y exploración física detalladas y una RMPD. Se analizaron alteraciones funcionales (anismo) y morfológicas (rectocele, enterocele, intususcepción, etc.).ResultadosLa exploración física no objetivó anomalías en 6 pacientes (20%). En 21 (70%) se diagnosticó un rectocele y en 2 (6,7%) un prolapso mucoso rectal. La RMPD evidenció laxitud del suelo pelviano en 22 casos (73,3%), enterocele en 4 (13,3%), sigmoidocele en 2 (6,7%), intususcepción en 8 (26,7%), prolapso mucoso rectal en 4 (13,3%), anismo en 3 (10%) y cistocele en 4 (13,3%). El rectocele fue el diagnóstico más frecuente, dándose en 26 pacientes (86,6%).Conclusiones La resonancia magnética ofrece una evaluación pelviana global con gran definición de los tejidos, no utiliza radiaciones ionizantes, es bien tolerada y nos aporta información complementaria para llegar al diagnóstico y plantear el mejor tratamiento en el síndrome de DO. Son necesarios estudios comparativos amplios frente a videodefecografía, considerada actualmente la técnica gold standard, que demuestren su superioridad o no respecto a esta (AU)

Introduction The aetiological diagnosis of obstructive defaecation syndrome (ODS) requires, among others, imaging tests. The purpose of this study is to descriptively analyse and compare the findings of dynamic pelvic magnetic resonance imaging (DPMRI) with the clinical examinations in patients with ODS. Material and methods A prospective comparative study was made between the physical examination and the DPMRI, with a descriptive analysis of the results. A total of 30 patients were included (2 males and 28 females), with a median age of 60 (range 23-76) years, with symptoms of ODS. An anamnesis and detailed physical examination and a DPMRI were performed on all of them. Functional (anismus) and morphological changes (rectocele, enterocele, intussusception, etc.), were analysed. Results The physical examination did not detect anomalies in 6 (20%) patients. A rectocele was diagnosed in 21 (70%) of the cases, and 2 (6.7%) a rectal mucosal prolapse. The DPMRI showed evidence of pelvic floor laxity in 22 (73.3%) cases, an enterocele in 4 (13.3%), a sigmoidocele in 2 (6.7%), intussusception in 8 (26.7%), rectal mucosal prolapse in 4 (13.3%), anismus in 3 (10%), and a cystocele in 4 (13.3%). The rectocele was the most frequent diagnosis, being given in 26 (86.6%) patients. Conclusions Magnetic resonance imaging provides an overall pelvic assessment with good definition of the tissues, and does not use ionising radiation, is well tolerated, and provides us with complementary information to arrive at the diagnosis, and establish the best treatment for ODS. Larger studies comparing videodefaecography (VD), currently considered the Gold Standard technique, are needed to be able to demonstrate whether it is superior or not to DPMRI (AU)

[Analysis of experience in the use of dynamic pelvic magnetic resonance imaging in the assessment of obstructive defaecation syndrome]. / Análisis de nuestra experiencia mediante el uso de resonancia magnética dinámica pelviana en la evaluación del síndrome de defecación obstructiva.

INTRODUCTION: The aetiological diagnosis of obstructive defaecation syndrome (ODS) requires, among others, imaging tests. The purpose of this study is to descriptively analyse and compare the findings of dynamic pelvic magnetic resonance imaging (DPMRI) with the clinical examinations in patients with ODS. MATERIAL AND METHODS: A prospective comparative study was made between the physical examination and the DPMRI, with a descriptive analysis of the results. A total of 30 patients were included (2 males and 28 females), with a median age of 60 (range 23-76) years, with symptoms of ODS. An anamnesis and detailed physical examination and a DPMRI were performed on all of them. Functional (anismus) and morphological changes (rectocele, enterocele, intussusception, etc.), were analysed. RESULTS: The physical examination did not detect anomalies in 6 (20%) patients. A rectocele was diagnosed in 21 (70%) of the cases, and 2 (6.7%) a rectal mucosal prolapse. The DPMRI showed evidence of pelvic floor laxity in 22 (73.3%) cases, an enterocele in 4 (13.3%), a sigmoidocele in 2 (6.7%), intussusception in 8 (26.7%), rectal mucosal prolapse in 4 (13.3%), anismus in 3 (10%), and a cystocele in 4 (13.3%). The rectocele was the most frequent diagnosis, being given in 26 (86.6%) patients. CONCLUSIONS: Magnetic resonance imaging provides an overall pelvic assessment with good definition of the tissues, and does not use ionising radiation, is well tolerated, and provides us with complementary information to arrive at the diagnosis, and establish the best treatment for ODS. Larger studies comparing videodefaecography (VD), currently considered the Gold Standard technique, are needed to be able to demonstrate whether it is superior or not to DPMRI.

The safety of magnetic resonance imaging in patients with programmable implanted intrathecal drug delivery systems: a 3-year prospective study.

BACKGROUND: It is common clinical practice to perform magnetic resonance imaging (MRI) in patients with indwelling programmable intrathecal drug delivery (IDD) systems, although the safety of the procedure has never been documented. We performed a single-center, 3-year, prospective evaluation in patients with a programmable implanted IDD to assess patient discomfort, IDD technical failures, and adverse effects during and after exposure to MRI. METHODS: Forty-three consecutive patients with an implanted programmable IDD system (SynchroMed® EL Implantable Infusion Pump, Model 8626L-18, and SynchroMed® II Model 8637-20, 8637-40; Medtronic, Inc., Minneapolis, MN) requiring a scheduled MRI evaluation were studied during a 3-year period. All MRI scans were performed with a 1.5-tesla clinical use magnet and a specific absorption rate of no more than 0.9 W/kg. Radiograph control was used to confirm postexposure pump rotor movement and detect system dislocations. IDD system failures, patient satisfaction, and discomfort were recorded. RESULTS: None of the patients experienced signs of drug overinfusion that could lead to hemodynamic, respiratory, or neurologic alterations. Radiologic evaluation after MRI revealed no spatial displacements of the intrathecal catheter tip or body pump, and programmer telemetry confirmed the infusion recovery. Patients' satisfaction after the procedure was high. CONCLUSION: Performing an MRI scan with the proposed protocol in patients with an implanted Medtronic programmable IDD system resulted in virtually no technical or medical complications.

Autoevaluación de una vía clínica para mejora del proceso quirúrgico carcinoma de recto / Self-evaluation of a clinical pathway to improve the results of rectal cancer

Objetivo Analizar si la autoevaluación de una vía clínica mejora los resultados del tratamiento del cáncer de recto (CR).Pacientes y método Pacientes intervenidos de CR divididos en 3 grupos según modificaciones bianuales de una vía clínica analizando diversos indicadores. Resultados Ciento sesenta y seis pacientes: grupo A: 2002–2003, n=50; B: 2004–2005, n=53 y C: 2006–2007, n=63; sin diferencias en edad, sexo o comorbilidad. El estudio preoperatorio mejoró con la introducción de TC toracoabdominopélvico: un 76% en el grupo C frente a un 6% del A (p<0,001). Todos los tumores del grupo C fueron estadificados mediante RM, ECO rectal o ambas, frente a un 84% del A (p<0,001). La tasa de amputaciones de recto pasó del 42% en el grupo A, al 17% en el C (p=0,007). Un 48% de cirujanos del grupo A frente al 94% en el C (p<0,001) tenían dedicación específica a la coloproctología. La media de adenopatías analizadas fue: grupo A: 6,2±4,5 frente a 13±6,5 en el C (p<0,001) y se informó del margen circunferencial en un 24% del grupo A frente al 76% en el C (p<0,001). Parámetros como la transfusión perioperatoria de hemoderivados, ingreso en UCI, uso de sonda nasogástrica, tolerancia precoz o analgesia epidural también mejoraron progresivamente. La mortalidad operatoria descendió de forma no significativa hasta el 4,7% y las dehiscencias anastomóticas del 24% al 9,5%, reduciéndose la estancia postoperatoria de 15–11 días (p=0,029).Conclusiones Se han mejorado múltiples indicadores de forma significativa en un período relativamente corto al efectuar autoevaluaciones del proceso (AU)

Objectives To analyse whether the self-evaluation of a clinical pathway improves the results of rectal cancer (RC) treatment. Patients and method Patients operated on for RC were divided into 3 groups according to biannual modifications of a clinical pathway analysing several indicators.Results166 patients: Group A: 2002–3 n=50, B: 2004–5 n=53 and C: 2006–7 n=63, without any differences in age, gender or comorbidity. Preoperative study improved with the introduction of CT scan: 76% in Group C vs. 6% in Group A (P<0.001). All Group C tumours were staged using MR, rectal ultrasound or both, compared to 84% in Group A (P<0.001). The rate of abdominal-perineal resections was reduced from 42% (Group A) to 17% (Group C); (P=0.007) and about 48% of surgeons in Group A vs. 94% in the C had a specific activity in coloproctology (P<0.001). The average lymph node count was: Group A=6.2±4.5 vs. 13±6.5 in the C and circumferential margin analysis was reported in 24% of Group A vs. 76% in Group C (P<0.001). Parameters such as perioperative blood transfusion, ICU admission, use of nasogastric tube, early feeding or epidural analgesia also improved progressively. Operative mortality decreased non-significantly to 4.7% and anastomotic leaks from 24% to 9.5% with a reduction in postoperative stay from 15 to 11 days during the period analysed (P=0.029).Conclusions Several indicators have significantly improved in a relatively short period of time due to self-evaluations of the process (AU)

[Self-evaluation of a clinical pathway to improve the results of rectal cancer]. / Autoevaluación de una vía clínica para mejora del proceso quirúrgico carcinoma de recto.

OBJECTIVES: To analyse whether the self-evaluation of a clinical pathway improves the results of rectal cancer (RC) treatment. PATIENTS AND METHOD: Patients operated on for RC were divided into 3 groups according to biannual modifications of a clinical pathway analysing several indicators. RESULTS: 166 patients: Group A: 2002-3 n=50, B: 2004-5 n=53 and C: 2006-7 n=63, without any differences in age, gender or comorbidity. Preoperative study improved with the introduction of CT scan: 76% in Group C vs. 6% in Group A (P<0.001). All Group C tumours were staged using MR, rectal ultrasound or both, compared to 84% in Group A (P<0.001). The rate of abdominal-perineal resections was reduced from 42% (Group A) to 17% (Group C); (P=0.007) and about 48% of surgeons in Group A vs. 94% in the C had a specific activity in coloproctology (P<0.001). The average lymph node count was: Group A=6.2+/-4.5 vs. 13+/-6.5 in the C and circumferential margin analysis was reported in 24% of Group A vs. 76% in Group C (P<0.001). Parameters such as perioperative blood transfusion, ICU admission, use of nasogastric tube, early feeding or epidural analgesia also improved progressively. Operative mortality decreased non-significantly to 4.7% and anastomotic leaks from 24% to 9.5% with a reduction in postoperative stay from 15 to 11 days during the period analysed (P=0.029). CONCLUSIONS: Several indicators have significantly improved in a relatively short period of time due to self-evaluations of the process.

MRI of mandibular osteonecrosis secondary to bisphosphonates.

OBJECTIVE: Bisphosphonates are a group of drugs used in the treatment of oncology patients with bone metastases. However, in the past few years, osteonecrosis of the jaw has been reported as a serious complication of such treatment. The objective of this study was to examine the use of MRI in the assessment of bone lesions caused by this disease. MATERIALS AND METHODS: Fourteen patients were studied who had been treated with i.v. bisphosphonates and had developed focal lesions of osteonecrosis of the jaw. These patients were referred by the stomatology department of Hospital General Universitario de Valencia. We evaluated both the morphology and the behavior of the lesions in T1, STIR, and after the administration of gadolinium. RESULTS: Twenty-six focal lesions were detected clinically and 36 were detected radiologically. All the clinically detected focal lesions were visible on MRI. There were 15 focal lesions detected radiologically that were not detected on clinical examination. In all patients, it was possible to assess bone involvement and involvement of the bone marrow, soft tissues, sinuses, and mandibular canal as well as the presence of adenopathy. CONCLUSION: MRI is an effective tool in the assessment of osteonecrosis of the jaw. The significance of focal lesions detectable on radiologic examination but without clinical correlation and their progression over time remains to be determined.

MRI evaluation of inflammatory activity in Crohn's disease.

OBJECTIVE: We wanted to assess the capability of MRI to quantitatively evaluate the therapeutic response to Crohn's disease (CD) relapse. SUBJECTS AND METHODS: Twenty patients with histologically proven CD were prospectively evaluated with MRI and ileocolonoscopy over a 2-year period. The MRI protocol included axial and coronal T2-weighted and contrast-enhanced T1-weighted sequences. MRI examinations were performed twice, once during an acute relapse of CD and the other at clinical remission. The terminal ileum and colon were divided into six segments/patient, and the endoscopy and histology findings were considered the standard of reference. These were compared on a segmental basis with the quantitative MRI findings regarding wall thickness and contrast enhancement. The results obtained in active and remission CD phases were likewise compared with the findings in 10 control subjects who underwent complete ileocolonoscopy for other reasons and had no pathological findings on ileocolonoscopy. RESULTS: Fifty three of 120 (44.2%) bowel segments showed pathologic changes on endoscopy and histology consistent with CD in active phase. On changing from the active disease phase to clinical remission, a significant decrease was observed in the wall thickness and contrast enhancement of the affected bowel wall. In the active phase of CD, the pathologic bowel segments presented with significantly greater contrast enhancement and wall thickness values compared with the healthy segments of CD and controls. On converting clinically into remission, contrast enhancement tended to normalize, whereas bowel wall thickness remained increased compared with the controls. CONCLUSION: MRI is able to detect pathologic bowel segments in CD, as it allows the measurement of significant variations in wall thickness and contrast enhancement on changing from the active phase of the disease to remission.