Development and validation of a diagnostic prediction model distinguishing complicated from uncomplicated diverticulitis

OBJECTIVES

Most diverticulitis patients (80%) who are referred to secondary care have uncomplicated diverticulitis (UD) which is a self-limiting disease and can be treated at home. The aim of this study is to develop a diagnostic model that can safely rule out complicated diverticulitis (CD) based on clinical and laboratory parameters to reduce unnecessary referrals.

METHODS

A retrospective cross-sectional study was performed including all patients who presented at the emergency department with CT-proven diverticulitis. Patient characteristics, clinical signs and laboratory parameters were collected. CD was defined as > Hinchey 1A. Multivariable logistic regression analyses were used to quantify which (combination of) variables were independently related to the presence or absence of CD. A diagnostic prediction model was developed and validated to rule out CD.

RESULTS

A total of 943 patients were included of whom 172 (18%) had CD. The dataset was randomly split into a derivation and validation set. The derivation dataset contained 475 patients of whom 82 (18%) patients had CD. Age, vomiting, generalized abdominal pain, change in bowel habit, abdominal guarding, C-reactive protein and leucocytosis were univariably related to CD. The final validated diagnostic model included abdominal guarding, C-reactive protein and leucocytosis (AUC 0.79 (95% CI 0.73-0.84)). At a CD risk threshold of ≤7.5% this model had a negative predictive value of 96%.

CONCLUSION

This proposed prediction model can safely rule out complicated diverticulitis. Clinical practitioners could cautiously use this model to aid them in the decision whether or not to subject patients to further secondary care diagnostics or treatment.

The ACCURE-trial: the effect of appendectomy on the clinical course of ulcerative colitis, a randomised international multicenter trial (NTR2883) and the ACCURE-UK trial: a randomised external pilot trial (ISRCTN56523019)

Background

Over the past 20 years evidence has accumulated confirming the immunomodulatory role of the appendix in ulcerative colitis (UC). This led to the idea that appendectomy might alter the clinical course of established UC. The objective of this body of research is to evaluate the short-term and medium-term efficacy of appendectomy to maintain remission in patients with UC, and to establish the acceptability and cost-effectiveness of the intervention compared to standard treatment.

Methods/Design

These paired phase III multicenter prospective randomised studies will include patients over 18 years of age with an established diagnosis of ulcerative colitis and a disease relapse within 12 months prior to randomisation. Patients need to have been medically treated until complete clinical (Mayo score <3) and endoscopic (Mayo score 0 or 1) remission. Patients will then be randomised 1:1 to a control group (maintenance 5-ASA treatment, no appendectomy) or elective laparoscopic appendectomy plus maintenance treatment. The primary outcome measure is the one year cumulative UC relapse rate - defined both clinically and endoscopically as a total Mayo-score ≥5 with endoscopic subscore of 2 or 3. Secondary outcomes that will be assessed include the number of relapses per patient at 12 months, the time to first relapse, health related quality of life and treatment costs, and number of colectomies in each arm.

Discussion

The ACCURE and ACCURE-UK trials will provide evidence on the role and acceptability of appendectomy in the treatment of ulcerative colitis and the effects of appendectomy on the disease course.

Trial registration

NTR2883; ISRCTN56523019

Laparoscopic resection rectopexy versus laparoscopic ventral rectopexy for complete rectal prolapse

BACKGROUND

Laparoscopic resection rectopexy (LRR) and laparoscopic ventral rectopexy (LVR) are favored for the treatment for rectal prolapse (RP) in the USA and Europe, respectively. This study aims to compare these two surgical techniques.

METHODS

All patients who underwent LRR because of RP between January 2000 and January 2012 at Cleveland Clinic Florida (Weston, FL, USA) were identified, and all relevant characteristics were entered in a database. This same analysis was also conducted for all patients who underwent LVR in the Meander Medical Center (Amersfoort, the Netherlands) between January 2004 and January 2012. These two cohorts were retrospectively compared with regard to complications, functional results and recurrence.

RESULTS

Twenty-eight patients (all female, mean age 50.1 years) were included in the LRR cohort at a mean follow-up of 57 (range 2-140; standard deviation (SD) ± 41.2) months. The LVR group consisted of 40 patients (36 females and 4 males) with a mean age of 67.0 years and a mean follow-up of 42 (range 2-82; SD ± 23.8) months. A significant reduction in constipation was observed in both cohorts after surgery: 57 versus 21% after LRR and 55 versus 23% after LVR (both P < 0.05). The incidence of incontinence also significantly decreased in both groups: 15% after LVR (55% before surgery) and 4% after LRR (61 % before surgery). Direct comparison of these two techniques showed a trend to significance (P = 0.09). Significantly, more complications occurred after LRR (n = 9: 1 major, 8 minor) then after LVR (n = 3: 2 major, 1 minor) (P < 0.05).

CONCLUSIONS

Both LVR and LRR are effective for the treatment for RP. Although both techniques offer significant improvements in functional symptoms, continence may be better after LRR. However, LRR also had a higher complication rate then did LVR.

Impact of symptom-reflux association analysis on long-term outcome after Nissen fundoplication

BACKGROUND

A positive symptom association probability (SAP) is regarded as an important selection criterion for antireflux surgery by many physicians. However, no data corroborate the relationship between symptom-reflux association and outcome, nor is it clear what impact a negative SAP has on the outcome of antireflux surgery in patients with abnormal oesophageal acid exposure. This study compared long-term outcomes of Nissen fundoplication in patients with a negative versus positive SAP.

METHODS

Five-year outcome of Nissen fundoplication in patients with proton-pump inhibitor (PPI)-refractory reflux and pathological acid exposure was compared between those with (SAP+, 109) and without (SAP-, 29 patients) a positive symptom association. Symptoms, quality of life (QoL), PPI use, endoscopic findings, manometry and acid exposure were evaluated.

RESULTS

At 5 years' follow-up, relief of reflux symptoms (95 versus 87 per cent), reduction in PPI use (80 to 25 per cent versus 85 to 14 per cent; P < 0·050) and improvement in QoL were similar in the SAP- and SAP+ groups. Reduction in acid exposure time (13·4 to 1·6 per cent versus 11·1 to 0·2 per cent of total time; P < 0·010), improvement in oesophagitis (44 to 6 per cent versus 61 to 13 per cent; P < 0·050) and increase in lower oesophageal sphincter pressure were also comparable.

CONCLUSION

The subjective and objective outcomes of fundoplication in patients with pathological acid exposure are comparable among those with a positive and negative SAP. Patients with pathological acid exposure and a negative SAP can also benefit from antireflux surgery.

Long-term outcome of Nissen fundoplication in non-erosive and erosive gastro-oesophageal reflux disease

BACKGROUND

Non-erosive (NERD) and erosive (ERD) gastro-oesophageal reflux disease (GORD) show similar severity of symptoms and impact on quality of life (QoL). Prospective data on long-term outcomes of antireflux surgery in NERD are lacking.

METHODS

Subjective and objective 5-year outcomes of Nissen fundoplication were compared in 96 patients with NERD and 117 with ERD, operated on for proton-pump inhibitor (PPI)-refractory GORD.

RESULTS

Preoperative and postoperative QoL, PPI use, acid exposure time, symptom-reflux correlation, lower oesophageal sphincter (LOS) pressure and reoperation rates were similar in the two groups. At 5 years, relief of reflux symptoms was similar (NERD 89 per cent versus ERD 96 per cent), PPI use showed a similar reduction (82 to 21 per cent versus 81 to 15 per cent respectively; both P < 0.001) and QoL score improved equally (50.3 to 65.2 (P < 0.001) versus 52.0 to 60.7 (P = 0.016)). Five patients with NERD developed erosions after surgery; oesophagitis healed in 87 per cent of patients with ERD. Reduction in total acid exposure time (NERD 12.7 to 2.0 per cent versus ERD 13.8 to 2.9 per cent; both P < 0.001) and increase in LOS pressure (1.3 to 1.8 kPa versus 1.2 to 1.8 kPa; both P < 0.001) were similar. The reintervention rate was comparable (NERD 15 per cent versus ERD 12.8 per cent).

CONCLUSION

Patients with PPI-refractory NERD and ERD benefit equally from Nissen fundoplication. The absence of mucosal lesions on endoscopy in patients with proven PPI-refractory reflux disease is not a reason to refrain from antireflux surgery.

[Complicated but successful resuscitation after amniotic fluid embolism]

A 33-year-old woman, gravida IV, para III with unexplained polyhydramnios was admitted to give birth at 29 weeks of pregnancy. Directly after the spontaneous breaking of the membranes, asystolia occurred. Following emergency resuscitation the sinus rhythm returned. Upon the relaparotomy due to a large filling requirement and increasing abdomen size, 'crush' lesions to the spleen and liver were visible; following this a splenectomy was carried out and tampons applied to the liver. After seven months the patient had slight residual symptoms; three weeks after his birth her son was transferred in good condition to another hospital. Amniotic fluid embolism is a rare complication of pregnancy with often serious complications for mother and child. The diagnosis is based on the clinical symptoms of cardiac arrest or sudden profound shock, acute respiratory failure, and/or disseminated intravascular coagulation, occurring in most cases during or soon after delivery, in the absence of an alternative cause (in particular primary cardiopulmonary causes). If the clinical picture deviates from the expected post-resuscitation course alternative diagnoses or resuscitation injuries must be considered.

Inter- and intraobserver variability of CT measurements obtained after endovascular repair of abdominal aortic aneurysms

OBJECTIVE

Important decisions are made on the basis of CT angiographic measurements of aneurysm size obtained after endovascular abdominal aortic aneurysm repair; however, little is known about the variability of these measurements. We evaluated the variability of CT angiographic measurements of aneurysm size obtained after endovascular abdominal aortic aneurysm repair.

MATERIALS AND METHODS

Thirty CT angiographic data sets were randomly chosen from 91 sets, including preoperative, postoperative, and follow-up CT images. All images were obtained according to a standardized acquisition protocol. On a workstation, three parameters were measured: maximum aneurysm diameter, maximum aneurysm cross-sectional area, and aneurysm volume. All data sets were measured twice by two investigators in a random order. The difference of each pair of measurements was plotted against the mean value. The mean difference and its standard deviation were calculated with a repeatability coefficient.

RESULTS

The intraobserver repeatability coefficient for observer 1 was 3.8 mm for diameter, 201.7 mm(2) for cross-sectional area, and 5.6 mL for volume. For observer 2, these figures were 3.0 mm, 219.0 mm(2), and 8.1 mL, respectively. The interobserver repeatability coefficients were 3.9 mm, 236.2 mm(2), and 10.3 mL.

CONCLUSION

Determination of the repeatability coefficient of aneurysm size measurements obtained after endovascular abdominal aortic aneurysm repair provides a good description of precision.

A simple technique to improve the accuracy of proximal AAA endograft deployment

PURPOSE

To report a technique for overcoming the positioning errors caused by angulation and rotation of the proximal aortic neck when anteroposterior fluoroscopic imaging is used during endograft deployment.

TECHNIQUE

Aortic neck angulation and rotation were measured preoperatively using spiral computed tomographic angiography in sagittal and axial projections. Before proximal graft deployment, the proximal end of the endograft was centered in the field of view, and the position of the C-arm was adjusted to the aortic neck angulation. Using this technique, optimal positioning of the endograft relative to the true position of the renal arteries can be achieved.

CONCLUSIONS

C-arm angulation and rotation is helpful in facilitating perfect positioning for an optimal seal between the endograft and the infrarenal aortic neck.

Dilatation of the proximal neck of infrarenal aortic aneurysms after endovascular AAA repair

OBJECTIVES

to assess size changes of the proximal aortic neck after endograft placement.

METHODS

since 1994, 54 consecutive patients have undergone abdominal aortic aneurysm (AAA) repair with the Endovascular Technologies (EVT) endograft. The study group comprised the 33 patients who had completed at least six months of the prospective follow-up protocol. The pre-, postoperative and follow-up helical computed tomography (CT) angiograms (CTAs) were processed on a workstation. The proximal neck dimensions were measured perpendicular to the central lumen line of the aortic neck. The cross-sectional area was measured at the proximal attachment system and at 1 cm proximal to the renal arteries.

RESULTS

while the dimensions of suprarenal aorta did not change, a significant dilatation of the proximal neck was found. The median increase was 10.3% at 6 months and 15.5% at 12 months. No correlation could be found between the amount of dilatation and pre- or postoperative neck-size, graft diameter and amount of graft-oversizing.

CONCLUSION

the infrarenal aortic neck demonstrates continued dilatation during follow-up after endograft placement.

[The operating room of the future]

Advances in computer technology will revolutionize surgical techniques in the next decade. The operating room (OR) of the future will be connected with a laboratory where clinical specialists and researchers prepare image-guided interventions and explore the possibilities of these techniques. The virtual reality is linked to the actual situation in the OR with the aid of navigation instruments. During complicated operations the images prepared preoperatively will be corrected during the operation on the basis of the information obtained peroperatively. MRI currently offers maximal possibilities for image-guided surgery of soft tissues. Simpler techniques such as fluoroscopy and echography will become increasingly integrated in computer-assisted peroperative navigation. The development of medical robot systems will make possible microsurgical procedures by the endoscopic route. Tele-manipulation systems will also play a part in the training of surgeons. Design and construction of the OR will be adapted to the surgical technology, and include an information and control unit where preoperative and peroperative data come together and from where the surgeon operates the instruments. Concepts for the future OR should be regularly adjusted to allow for new surgical technology.

Preoperative imaging of the aortoiliac anatomy in endovascular aneurysm surgery

Endovascular aneurysm repair (EAR) requires precise measurement of aortoiliac lengths and diameters to select the most suitable endograft. A combination of computed tomography (CT) scanning and contrast arteriography is usually applied for this purpose. We have investigated whether spiral CT angiography with specialized data processing (CTA) may replace these imaging methods as a sole technique for sizing of endografts for EAR and present these data as a background for discussion of preoperative imaging before EAR. Typical measurements for EAR were performed using CTA, conventional CT scanning, and arteriography. The resulting measurements were compared, and their consequences on graft selection were studied. Graft diameters based on arteriography were too small in 62% of the patients, as compared with CTA. The difference in length sizing between CTA and arteriography never exceeded 1 cm. A similar graft diameter was selected by conventional CT scan and CTA in 81% of the patients, whereas minor graft oversizing by conventional CT scan was found in 14% of the patients. Length sizing by conventional CT scanning resulted in underestimation of graft length in 91% of the patients. Neither conventional CT scanning nor arteriography is adequate as a sole preoperative radiological investigation for endograft sizing in EAR. Spiral CTA with special processing combines the specific advantages of both imaging techniques and should be regarded as the method of first choice for this purpose.

Length measurements of the aorta after endovascular abdominal aortic aneurysm repair

BACKGROUND

successful endovascular repair of abdominal aortic aneurysms (AAA) generally leads to a decrease in aneurysm size. Theoretically, this may lead to foreshortening of the excluded segment. If so, vertically rigid endografts may dislocate over time and cover renal or hypogastric arteries.

AIM

to assess length changes of the infrarenal aorta after endovascular AAA exclusion.

PATIENTS AND METHODS

forty-four consecutive patients were scheduled for the EndoVascular Technologies endograft, a vertically non-rigid prosthesis which would potentially accommodate longitudinal changes. Twenty-four patients had completed at least 6 months of follow-up. In 18/24 patients a decrease in size was established by aneurysm volume measurements at 6 months' follow-up. Helical computer tomography (CT) angiograms were processed on a workstation. Aortic lengths were measured along the central lumen line from the lower renal artery orifice to the native aortic bifurcation. The computer tomography angiogram (CTA) reconstruction thickness of 2 mm yields at least a 4-mm error for each length measurement.

RESULTS

in the shrinking aneurysm group, the median length change was 0 mm (range -9 mm to +4 mm) at 6 months' follow-up (n =18) and also 0 mm (range -7 mm to +4 mm) at 12 months' follow-up ( n =10). In 16/18 patients, length changes remained within the measurement error range of 4 mm.

CONCLUSION

in this group of shrinking aneurysms after endovascular AAA repair, foreshortening of the excluded aortic segment appears not to be a clinically significant problem.

Mid-term fixation stability of the EndoVascular Technologies endograft. EVT Investigators

AIM OF THE STUDY

to determine the positional stability of the EndoVascular Technologies (EVT) endograft after endovascular aneurysm repair during morphologic changes of the abdominal aorta during follow-up.

PATIENTS AND METHODS

all patients treated worldwide with an EVT endograft with an adequate postoperative and at least 12 months postoperative CT scan were included (n=125). Endograft migration was investigated by recording the position of the endograft attachment systems relative to the renal arteries and the aortic or iliac bifurcations. The vertical body axis served as a scale to quantify migration. Aortic cross-sectional areas were measured in the suprarenal aorta and in the proximal and distal aneurysm necks. Length changes of the infrarenal aorta during follow-up were measured, comparing the distance between the left renal artery and the aortic bifurcation.

RESULTS

the median follow-up was 24 months (range 12-48 months). Graft migration was identified in 4 out of 125 patients (3%). Significant infrarenal aortic dilation was observed at the proximal and distal aneurysm neck during follow-up. However, aortic neck dilation was not associated with endograft migration. The length of the infrarenal aorta did not change significantly after endovascular repair.

CONCLUSION

fixation by stents containing hooks of the EVT design appear to be effective in preventing migration of endografts with an unsupported trunk for up to four years. A stable position was maintained in spite of changes in cross-sectional areas of the aneurysm neck.

The role of infrarenal aortic side branches in the pathogenesis of endoleaks after endovascular aneurysm repair

AIM

To investigate the relation between the number of preoperative patent side branches and the presence or absence of postoperative endoleaks, and to study the fate of patent branches after operation.

PATIENTS AND METHODS

Thirty consecutive patients were included. Cine mode viewing of axial CT angiography images was applied to detect infrarenal aortic side branches. The position of side branches relative to the renal arteries, branch patency and run-off pathways were studied.

RESULTS

A total of 160 patent side branches were found. All patients had two or more patent side branches. A patent inferior mesenteric artery was found in 22/30 patients (73%). Postoperative CT scans revealed major endoleaks in five patients (16%) and minor endoleaks in eight (27%). There was no significant difference in the number of preoperative patent side branches in patients with a completely thrombosed aneurysm sac (five; range 2-8) compared to patients with postoperative endoleaks (six; range 3-9; p = 0.12). Backbleeding from patent side branches as the sole cause of endoleak was seen in one patient only (3.3%).

CONCLUSION

Postoperative endoleaks are not related to the number of preoperative patent side branches. In patients without endoleaks, contrast enhancement of side branches was repeatedly seen in the vicinity of the aneurysm wall. Although close follow-up of these branches is warranted, they did not affect the outcome of endovascular aneurysm repair.

The efficacy of transfemoral endovascular aneurysm management: a study on size changes of the abdominal aorta during mid-term follow-up

OBJECTIVES

The aim of this study was to assess efficacy of transfemoral endovascular aneurysm management (TEAM) during mid-term follow-up.

DESIGN

Prospective multicentre study.

MATERIALS AND METHODS

In 26 patients treated by a Tube Endograft, the pre- and postoperative contrast enhanced computed tomography (CT) images were reviewed in a blinded fashion. Aortic diameters were measured at the coeliac trunk, the inferior and superior aneurysm neck and the level of the maximal aneurysm size. The changes in diameter were related to the presence or absence of an endoleak.

RESULTS

The median follow-up was 12 months. In 10 patients an endoleak was found. Three endoleaks sealed spontaneously within 30 days after operation. All aneurysms with persistent endoleaks expanded, at a median rate of 0.30 mm per month. Four patients were converted between 9 and 14 months after TEAM. Aneurysms excluded by the endoprosthesis showed a median shrinkage of 0.41 mm per month. The inferior aneurysm neck demonstrated significant growth during follow-up, unrelated to endoleaks.

CONCLUSIONS

This study demonstrated the efficacy of TEAM in discontinuing the process of aneurysm expansion. Complete seal of the aneurysm sac after TEAM leads to shrinkage or arrest of growth of the aneurysm, while persistent endoleak is associated with progressive expansion.

Preoperative sizing of grafts for transfemoral endovascular aneurysm management: a prospective comparative study of spiral CT angiography, arteriography, and conventional CT imaging

PURPOSE

To define the impact of spiral computed tomographic angiography (CTA) with image reconstruction on graft selection for Transfemoral Endovascular Aneurysm Management (TEAM) by comparing it to conventional computed tomography (CT) and contrast arteriography.

METHODS

Twenty-one candidates for TEAM were included. The diameters of the superior and inferior aneurysm necks and lengths between the graft attachment sites were measured using the three imaging techniques. These measurements and their consequences on graft selection were studied.

RESULTS

The difference in length sizing between spiral CTA and arteriography never exceeded 1 cm; however, lengths measured by conventional CT scanning resulted in underestimation of graft length in 91% of patients. Graft diameters were chosen too small in 62% of the patients when based on arteriographic diameter measurements. A graft of similar diameter was selected by spiral CTA and conventional CT scanning in 81% of the patients, while minor oversizing by conventional CT scanning was found in 14%.

CONCLUSIONS

Neither conventional CT scanning nor arteriography is adequate as a sole preoperative radiological investigation for TEAM graft sizing. Spiral CTA with image processing produces all information required for selection of the optimal graft size and should be regarded the method of first choice for this purpose.

[(Procto)colectomy with permanent ileostomy versus restorative proctocolectomy in ulcerative colitis; the past as background for the present]

In the University Hospital of Utrecht, in order to assess the value of 'restorative' proctocolectomy, the early and late complications after 'classical' (procto)colectomy with establishment of a permanent ileal stoma were evaluated retrospectively over the period 1969-1988. The inclusion criteria were: having undergone a (procto)colectomy with establishment of an ileal stoma because of pathologico-anatomically confirmed ulcerative colitis, with follow-up in the clinic mentioned. Data on the preoperative period, on the operation and on the early and late complications were collected of 101 patients. Immediately postoperative complications were encountered in 50% of the patients. Mortality was 2% in the group as a whole and 5% after emergency surgery. Late complications occurred in 62% of the patients, and in 45% of the patients they necessitated one or several reoperations. Sources of late complications included: the rectal stump left in situ, the perineal wound area, the stoma and the formation of abdominal adhesions. Classical (procto)colectomy with establishment of a permanent ileal stoma entails a large proportion of early and late postoperative complications. It is asserted that the complications at present observed after restorative proctocolectomy must not prompt a return to classical proctocolectomy as the standard surgical treatment of ulcerative colitis.

Spontaneous pneumomediastinum in children

Spontaneous pneumomediastinum is defined as a non-traumatic mediastinal air leak in patients without underlying lung disease. In children it is rarely diagnosed but is likely to be often missed. We have made a comprehensive review of the literature on spontaneous pneumomediastinum in children. The aetiopathogenesis, incidence, clinical features, diagnosis and treatment are discussed. We suggest that spontaneous pneumomediastinum in children is underdiagnosed.