Correlation between Preoperative Imaging and Intraoperative Risk Assessment in the Prediction of Postoperative Pancreatic Fistula Following Pancreatoduodenectomy

Background

Prediction of postoperative pancreatic fistula (POPF) can be carried out with the intraoperative assessment of pancreatic consistency (PC) and via pancreatic duct width (iPDW). Preoperative computed tomography (CT) calculated pancreatic remnant volume (PRV) and duct width (rPDW) have also been shown to offer useful information about the risk of POPF.

Objective

The objective of this study was to determine the predictive value of the preoperative radiological features as compared with the intraoperative risk estimation for the subsequent development of POPF.

Method

All patients undergoing pancreatoduodenectomy between September 2007 and March 2012 at the Karolinska University Hospital Stockholm were included. PRV and rPDW were determined on preoperative CT and in parallel, intraoperative PC and iPDW of the remnant pancreas were independently assessed.

Results

A total of 296 consecutive pancreatoduodenectomies were included. POPF occurred in 45 patients (15.2 %). Of those with a preoperatively calculated PRV < 23.0 cm³, 2.8 % developed POPF compared with 25.7 % of those with a corresponding volume > 46.0 cm³. In patients with an rPDW > 7.0 mm, 4.1 % had a POPF as compared with 38.7 % for those with rPDW < 2.0 mm. The POPF risk estimates based on PRV and rPDW and the intraoperative risk assessments were found to be identical (p < 0.001). In the receiver operating characteristic analysis, area under the curve was 0.80 (95 % confidence interval [CI] 0.72–0.87) and 0.80 (95 % CI 0.72–0.88) for the CT-based and intraoperative risk prediction models, respectively.

Conclusions

Preoperative CT-based and intraoperative gland risk assessments offer comparable predictive information on the risk of POPF after pancreatoduodenectomy. These results imply that accurate POPF risk estimation can be carried out in the preoperative setting to opt for improved patient selection into relevant research protocols and the availability of surgical expertise and techniques.     

Clinical Implementations of Preoperative Computed Tomography Lymphography in Gastric Cancer: A Comparison with Dual Tracer Methods in Sentinel Node Navigation Surgery

Background

Current sentinel node (SN) detection techniques require a learning period and tracers have many disadvantages for practical use. The purpose of this study was to evaluate the feasibility of preoperative computed tomography (CT) lymphography using lipiodol for detecting SNs in gastric cancer.

Methods

A total of 24 patients who underwent laparoscopic surgery for early gastric cancer were enrolled in this study. Noncontrast CT images were obtained 1–2 h after endoscopic submucosal peritumoral injection of 1 mL of lipiodol the day before surgery. The final sentinel basins (SBs) were decided by the dual tracer method (indocyanine green plus ^99mTc-antimony sulfur colloid) during laparoscopic gastrectomy. SN detection rate by preoperative CT lymphography using lipiodol and agreement between CT lymphography versus dual tracer method were evaluated. The agreement was confirmed with soft X-ray radiography of detected SBs.

Results

Technical failure of endoscopic lipiodol injection occurred in one patient. SNs were successfully detected in the remaining 23 patients (95.8 %), whereas the intraoperative SB detection rate using the dual method was 100 %. The agreement rate, defined as the concordance between two methods or inclusion of SNs detected by CT lymphography in SBs by the dual tracer method, was 87 %.

Conclusions

Our initial experience of CT lymphography using lipiodol shows good potential in predicting SBs of gastric cancer preoperatively. However, SN detection by CT lymphography and the dual method should be applied complementarily in gastric cancer because discrepancies between these methods occur.     

Usefulness of Contrast-Enhanced Intraoperative Ultrasonography (CE-IOUS) in Patients with Colorectal Liver Metastases after Preoperative Chemotherapy

Aims

The aim of this study was to evaluate the ability of contrast-enhanced intraoperative ultrasonography to detect colorectal liver metastases after preoperative chemotherapy compared with intraoperative ultrasound and preoperative imaging techniques.

Methods

From January 2010 to December 2011, 28 patients with colorectal liver metastases underwent intraoperative ultrasonography and contrast-enhanced intraoperative ultrasonography during hepatectomy following preoperative chemotherapy. The findings were compared to preoperative imaging using contrast-enhanced ultrasonography, computed tomography, magnetic resonance imaging, and/or fluorodeoxyglucose positron emission tomography.

Results

Preoperative imaging techniques detected 58 metastatic lesions in 28 patients. In 32 % of patients (n?=?9), intraoperative ultrasound detected 24 missed hepatic nodules. In 14 % of patients (n?=?4), contrast-enhanced intraoperative ultrasonography detected an additional six nodules and change in operative management occurred in 18 % of patients. Using univariate analysis, we found three factors significantly related to detection of additional metastases with contrast-enhanced intraoperative ultrasonography: three or more metastases before chemotherapy (p?=?0.047), resolution of at least one metastasis (p?=?0.011), and small liver metastases (largest lesion size ≤20 mm) after chemotherapy (p?=?0.007).

Conclusion

In patients undergoing surgery for colorectal liver metastases after chemotherapy, contrast-enhanced intraoperative ultrasonography improved both the sensitivity of intraoperative ultrasonography to detect liver metastases and the R0 hepatic resection rate.     

Computer-based quantification of the Achilles tendon thickness in sequential B-mode ultrasound images: a study of feasibility and reliability

Introduction

Assessment of the Achilles tendon thickness (ATT) using B-mode ultrasound is a common technique for clinical evaluation of chronic mid-part tendinosis. Currently used image-based assessment is limited by relatively high inter- and intra-observer variability. In this study, it was tested whether a new sequence-based automated assessment of ATT provides more reliable and reproducible results than the standard image-based procedure.

Materials and methods

A total of 118 non-operated tendons of 59 healthy subjects (44, range 28–50 years) were analysed using an automated image based as well as a newly developed automated sequence-based method. Correlation and agreement of both methods were evaluated. The root mean square deviation (RMSD) and a Bland–Altman analysis were performed to highlight observer (n = 18 tendons) as well as reader (n = 40 tendons) dependent variabilities of both methods.

Results

A strong correlation was found between image and sequence-based ATT assessment (p = 0.92). The Bland–Altman analysis showed a good agreement between both methods (mean difference 0.0018, 95 % CI: ?0.046; 0.05). In repetitive examinations, sequence-based analysis showed a significant reduction concerning reader- and observer-dependent variability compared to image-based assessment. The RMSD for repetitive sequence-based measurements was approximately 0.3 mm (compared to 0.6 mm for image-based measurement), respectively.

Conclusions

The study shows sequence-based automated assessment of ATT being clearly superior to the standard image-based procedure. The new method provides a clear reduction of reader as well as observer-dependent variability. Due to the decreased scattering of measurement data sequence-based measurement seems especially valuable for quantification of small tendon thickness changes such as exercise-induced hypertrophy.     

The Value of Preoperative Imaging in Small Bowel Neuroendocrine Tumors

Background

Neuroendocrine tumors of the small bowel (SBNETs) are a rare but important subgroup of malignancies. Since 30 % of SBNETs present with metastatic disease, often with an occult primary, preoperative imaging is critical for determining who will benefit most from abdominal exploration. We set out to evaluate the usefulness of the two most commonly performed imaging modalities in predicting the extent of disease found at exploration in patients with SBNETs.

Methods

A retrospective chart review was performed on patients with SBNETs resected at 1 institution. Data from preoperative computed tomography (CT) scans were reviewed to determine whether the primary tumor, nodal, or liver metastases were seen, then compared with intraoperative findings. Results of preoperative somatostatin receptor scintigraphy (SRS) were similarly examined.

Results

A total of 62 patients with SBNETs were included. Of these patients, 42 of 62 (68 %) had distant metastases and 48 of 62 (77 %) had nodal metastases at exploration. A total of 56 patients had preoperative CT scans and 47 had SRS. Using CT, a primary tumor was localized to the small bowel in 27 of 56 (48 %) and nodal metastases seen in 33 of 56 (79 %) of cases. SRS found intra-abdominal uptake in 35 of 47 cases (74 %).

Conclusions

CT and SRS are complementary in making the diagnosis of SBNET, with CT giving more precise anatomical detail, while SRS helps to confirm that lesions are NETs and is useful for identifying occult extrahepatic sites of metastatic disease. However, 10–15 % of SBNETs were not identified by either test preoperatively, and therefore surgical exploration still plays an important role in making the diagnosis in these patients.     

Volume and densities of chronic subdural haematoma obtained from CT imaging as predictors of postoperative recurrence: a prospective study of 107 operated patients

Background

Chronic subdural haematoma (CSDH) is a common entity in neurosurgery with a considerable postoperative recurrence rate. Computerised tomography (CT) scanning remains the most important diagnostic test for this disorder. The aim of this study was to characterise the relationship between the recurrence of CSDH after treatment with burr-hole irrigation and closed-system drainage technique and CT scan features of these lesions to assess whether CT findings can be used to predict recurrence.

Methods

We investigated preoperative and postoperative CT scan features and recurrence rate of 107 consecutive adult surgical cases of CSDH and assessed any relationship with univariate and multivariate regression analyses.

Results

Seventeen patients (15.9 %) experienced recurrence of CSDH. The preoperative haematoma volume, the isodense, hyperdense, laminar and separated CT densities and the residual total haematoma cavity volume on the 1st postoperative day after removal of the drainage were identified as radiological predictors of recurrence. If the preoperative haematoma volume was under 115 ml and the residual total haematoma cavity volume postoperatively was under 80 ml, the probability of no recurrence was very high (94.4 % and 97.4 % respectively).

Conclusions

These findings from CT imaging may help to identify patients at risk for postoperative recurrence.     

Significance of preoperative 3D-CT angiography for localization of the femoral artery in complicated THA

Background

Major vascular injury is one of the most devastating complications in total hip arthroplasty (THA). Risk for intraoperative vascular injury is increased when the normal vascular anatomy is distorted by previous surgery or dislocation with displacement. Therefore, an appreciation of the vascular anatomy in relation to the anticipated surgical field is critical to avoid this complication during preoperative assessment for a complicated THA.

Methods

Preoperative three-dimensional (3D) CT angiography was performed for 24 complicated THAs when altered vascular anatomy around the acetabulum was suspected. When assessing the CT images, the presence of apparent proliferation of vessels close to the original acetabulum as well as a distance of <10 mm from the artery to the acetabulum was deemed a potential risk factor for intraoperative vascular injury. Additionally, the relationships of clinical characteristics and the presence of these risk factors were analyzed to identify the patient population at risk.

Results

The incidence of proliferation of collateral vessels was higher in patient groups with proximal femoral migration of 5 cm or more and multiple previous surgeries prior to the index THA. Moreover, in three ankylosed hips, lateral deviation of the main vascular trunk with an artery–acetabulum distance of <10 mm was identified in all cases.

Conclusion

Preoperative 3D-CT angiography in cases of complicated THA revealed altered vascular anatomy which may increase the risk for intraoperative vascular injuries. Patient characteristics related to the risk for this complication were marked proximal femoral migration, multiple previous surgeries, and hip ankylosis. Preoperative image examination of the vascular anatomy is thought to help reduce the risk of inadvertent vascular injury in these complicated THA cases.     

A prospective comparative study of the role of CT and MRI-MRCP in the preoperative assessment of obstructive jaundice and their intraoperative corroboration

Background

To compare the diagnostic accuracy of computed tomography (CT) and magnetic resonance imaging-magnetic resonance cholangiopancreatography (MRI-MRCP) in assessing the level and cause of obstruction in patients with obstructive jaundice, and to corroborate the preoperative diagnostic accuracy of MRI-MRCP and CT with operative findings.

Methods

This prospective study included 40 patients with operable obstructive jaundice, whose ages ranged between 20 and 70 years. Diagnosis was based on clinical history, physical examination, biochemical examination, and ultrasonography, followed by CT and MRI-MRCP. The findings of these imaging modalities were compared with intraoperative findings. A statistical analysis was performed to determine the efficacy of CT scanning and MRI-MRCP.

Results

CT is a better modality for diagnosing malignant causes of obstructive jaundice while MRI-MRCP shows excellent results in detecting benign causes.

Conclusion

MRI-MRCP is an excellent modality for the detection of common bile duct stones, but it has its limitations regarding visualization of the periampullary region, whereas CT scanning proved to be useful in delineating the malignant causes of obstruction.     

Three-tesla MRI biphasic angiography: a method for preoperative assessment of the vascular supply in renal tumours—a surgical perspective

Purpose

The new generation of 3TMRI has improved spatial and time resolutions, which are favourable in imaging of the renal vasculature. In this study, we have compared the imaging findings of the renal blood vessels using 3TMRI and CT with intraoperative assessment of the renal vasculature as gold standard.

Methods

This prospective study was approved by the local ethical committee. Between 4/2011 and 12/2011, 80 patients with renal tumours underwent 3TMRA (angiography) (Magnetom SKYRA 3T, Siemens). Twenty of the patients were also examined with CT AG. The results of the CTA- and MRA-imaging studies were correlated with the intraoperative assessment of the renal vessels.

Results

Seventy patients (87.5 %) had a detailed intraoperative assessment of the renal vessels. The sensitivities for CTA and MRA were 88.2 and 88.6 %, respectively. All discrepancies between imaging studies and intraoperative findings were due to inability to identify small polar vessels. The results of MRA were concordant with CTA in 85.0 % of cases. The (three) discrepancies between MRI and CT were due to failure of MRI in identifying small polar vessels.

Conclusions

(1) 3TMRA gives detailed information about the renal vasculature including its topographical anatomy. (2) With MRI, small aberrant vessels are more frequently missed than with CTA. (3) CTA remains the gold standard. However, MRA may be used for planning of laparoscopic operations. (4) The quality of the 3D reconstruction is highly depending on the skills of the radiologist.     

Thoracoscopic interbody fusion with percutaneous posterior stabilization for thoracic and thoracolumbar injuries

Background context

Traumatic thoracolumbar discoligamentous injuries and partial burst fractures are commonly managed through posterior-only stabilization. Many cases present later with failure of posterior implant and progressive kyphotic deformities that necessitates major surgeries. Anterior interbody fusion saves the patients unnecessary long-segment fixation and provides a stable definitive solution for the injured segment.

Purpose

The purpose of this study is to assess the clinical and radiographic outcomes of combined minimal invasive short-segment posterior percutaneous instrumentation and anterior thoracoscopic-assisted fusion in thoracolumbar partial burst fractures or discoligamentous injuries.

Study design

Prospective observational study.

Patient sample

Thirty patients with acute thoracic or thoracolumbar injuries operated upon between December 2007 and January 2009.

Outcome measures

Oswestry Disability Index (ODI), clinical and neurological examination for clinical assessment. Plain X-ray for radiological evaluation.

Methods

Preoperative evaluation included clinical and neurological examination, plain X-rays, computed tomography (CT), and magnetic resonance imaging (MRI). Posterior short-segment percutaneous stabilization plus anterior thoracoscopically assisted fusion in prone position were done. The minimum follow-up period was 2 years (range 24–48 months).

Results

The mean age was 44 years. The commonest affected segment was between T10 and L1 (22 patients, 73 %). The mean total operative time was 103 min. The mean operative blood loss was 444 ml. Interbody fusion cage was used in 28 patients while iliac graft in two cases. Fusion rate at the final follow-up was 97 % (29 patients); one patient did not show definitive fusion although he was clinically satisfied. The mean final follow-up ODI was 12 %. The mean preoperative kyphosis angle was 22° improved to 6.5° postoperatively and was 7.5° at final follow-up. There were no major intraoperative or postoperative complications.

Conclusion

Combined anterior thoracoscopic fusion and short-segment posterior percutaneous instrumentation showed good clinical and radiographic outcomes in cases of thoracolumbar injuries through limiting the instrumented levels and preventing progress of posttraumatic kyphosis.     

Effects of abdominal surgery through a midline incision on postoperative trunk flexion strength in patients with colorectal cancer

Background

Abdominal surgery with bowel resection through a midline or transverse incision is performed in most cases of colorectal cancer (CRC). Both incisions affect abdominal wall function and may lead to differences in postoperative clinical outcomes. Although postoperative isometric trunk flexion strength (ITFS) has previously been investigated, the results were based on measurement tools distinguished by poor reproducibility and validity.

Objective

To evaluate the reproducibility of and variations in ITFS following abdominal surgery using a dynamometer and explore the correlation between ITFS and the scar length.

Method

The study group consisted of 22 consecutive patients (15 men and 7 women) referred for surgery. The outcome parameters included ITFS which was measured using a fixed dynamometer and a digital manometer, scar length, weight and pain. Test–retest measurement (3 h apart) of ITFS was taken 1 day before surgery to determine the instruments’ reproducibility. Additional measurements of the outcome parameters were taken 1 and 6 weeks postoperatively.

Results

Excellent test–retest correlations (ICC > 0.85) coupled with low standard error of the measurement for both the ITFS and the manometric findings indicated clinically acceptable reproducibility of the findings. Significant pre- and postoperative differences in ITFS were noted using both techniques. Six weeks postoperatively, fair and significant correlations were noted between the dynamometry-based ITFS and both the scar length (r = 0.452) and age (r = 0.498). Of note, scar length and preoperative dynamometric ITFS predicted ITFS 6 weeks postoperatively (F = 102.949, p < 0.001, R ² = 0.92).

Conclusions

Measurements of ITFS using dynamometry in elective CRC patients are reproducible, sensitive to clinical changes and allow prediction of postoperative ITFS scores based on their preoperative counterparts.     

Retrospective comparison of measured stone size and posterior acoustic shadow width in clinical ultrasound images

Purpose

Posterior acoustic shadow width has been proposed as a more accurate measure of kidney stone size compared to direct measurement of stone width on ultrasound (US). Published data in humans to date have been based on a research using US system. Herein, we compared these two measurements in clinical US images.

Methods

Thirty patient image sets where computed tomography (CT) and US images were captured less than 1 day apart were retrospectively reviewed. Five blinded reviewers independently assessed the largest stone in each image set for shadow presence and size. Shadow size was compared to US and CT stone sizes.

Results

Eighty percent of included stones demonstrated an acoustic shadow; 83% of stones without a shadow were ≤ 5 mm on CT. Average stone size was 6.5 ± 4.0 mm on CT, 10.3 ± 4.1 mm on US, and 7.5 ± 4.2 mm by shadow width. On average, US overestimated stone size by 3.8 ± 2.4 mm based on stone width (p < 0.001) and 1.0 ± 1.4 mm based on shadow width (p < 0.0098). Shadow measurements decreased misclassification of stones by 25% among three clinically relevant size categories (≤ 5, 5.1–10, > 10 mm), and by 50% for stones ≤ 5 mm.

Conclusions

US overestimates stone size compared to CT. Retrospective measurement of the acoustic shadow from the same clinical US images is a more accurate reflection of true stone size than direct stone measurement. Most stones without a posterior shadow are ≤ 5 mm.

     

The effectiveness of skeletal imaging for quality assessment in posterior cruciate ligament reconstruction: reliability and validity of radiographs and computed tomography

Purpose

For intra- and postoperative evaluation of precise and anatomic graft tunnel position, radiographs (XR) and computed tomography (CT) scans have been suggested. The purpose of this study was to evaluate the reliability and validity of XR and CT for quality assessment following PCL reconstruction.

Methods

Postoperative radiographs and CT scans were obtained in 45 consecutive patients following a standard single-bundle PCL reconstruction. Femoral and tibial tunnel apertures were correlated to femoral and tibial measurement grid systems. To assess the reliability and validity of XR and CT scans three independent observers evaluated radiographic and CT images for the position of femoral and tibial tunnel apertures.

Results

Almost perfect inter- and intra observer agreement (0.79–0.99) was found for all CT measurements except for the distance of the tunnel position to the previous physis line. Almost perfect and strong inter- and intraobserver agreement (0.70–0.98) was found for all tibial measurements on XR which tended to increase with repeated interpretation and to decrease with low levels of observer qualification. Femoral measurements yielded only poor-to-moderate reliability (0.02–0.5) between raters on XR but strong intraagreement within experienced observers (0.45–0.86). Specificity for XR was calculated with 75.7 % for P2 and P3 and with 71 % for femoral tunnel depth and height.

Conclusion

XR and CT represent complementary imaging modalities and both offer considerable accuracy and precision for the determination of femoral and tibial tunnel apertures following PCL reconstruction and can be recommended for intra- and postoperative quality assessment.     

Laser method for intraoperative evaluation of lower extremity alignment: comparison of a novel technique to CT and a conventional method

Introduction

Accurate restoration of mechanical alignment is an important factor in reconstructive surgery of the lower extremity. Conventional intraoperative methods, such as using an electrocautery cable, provide only a momentary evaluation of alignment. In this study, we evaluated a novel technique using a laser emitter, which projected the mechanical axis of the lower extremity, providing continuous intraoperative information on alignment.

Materials and methods

Alignment of 16 cadaver lower extremities was measured using the electrocautery cable method, the laser method, and CT scan as the standard measurement. The mechanical axis was defined by a line from the center of the femoral head to the center of the ankle. For simplifying measurements the intersection with the tibial plateau was divided into percentages from the medial border (0 %) to the lateral border (100 %). For using the laser method a laser emitting and laser catching device was developed, which is positioned and centered on the femoral head and the ankle using an image intensifier. By catching the laser on the knee region the actual mechanical axis is marked.

Results

The data demonstrated good correlation of the laser method when compared to the cable method (P = 0.44). Comparison of the average mechanical axis between cable method and CT (P = 0.819) and laser method and CT (P = 0.647) did not show a statistically significant difference. Average radiation time in comparison between cable method and laser method showed a statistically significant difference (P = 0.013), with the laser method requiring more radiation time.

Conclusion

Determination of the mechanical axis during surgery remains a difficult clinical problem. Restoration of alignment is an important prognostic factor for surgical outcome. Based on these data, the laser method represents a simple, yet effective tool for continuous intraoperative evaluation of lower extremity alignment.     

Stimulation sites in the subthalamic nucleus projected onto a mean 3-D atlas of the thalamus and basal ganglia

Background

In patients with severe forms of Parkinson’s disease (PD), deep brain stimulation (DBS) commonly targets the subthalamic nucleus (STN). Recently, the mean 3-D Morel-Atlas of the basal ganglia and the thalamus was introduced. It combines information contained in histological data from ten post-mortem brains. We were interested whether the Morel-Atlas is applicable for the visualization of stimulation sites.

Methods

In a consecutive PD patient series, we documented preoperative MRI planning, intraoperative target adjustment based on electrophysiological and neurological testing, and perioperative CT target reconstruction. The localization of the DBS electrodes and the optimal stimulation sites were projected onto the Morel-Atlas.

Results

We included 20 patients (median age 62 years). The active contact had mean coordinates X_lat?=?±12.1 mm, Y_ap?=??1.8 mm, Z_vert?=??3.2 mm. There was a significant difference between the initially planned site and the coordinates of the postoperative active contact site (median 2.2 mm). The stimulation site was, on average, more anterior and more dorsal. The electrode contact used for optimal stimulation was found within the STN of the atlas in 38/40 (95 %) of implantations.

Conclusions

The cluster of stimulation sites in individual patients—as deduced from preoperative MR, intraoperative electrophysiology and neurological testing—showed a high degree of congruence with the atlas. The mean 3D Morel Atlas is thus a useful tool for postoperative target visualization. This represents the first clinical evaluation of the recently created atlas.     

Predictors of Negative Intraoperative Findings at Emergent Laparotomy in Patients with Cirrhosis

Background

Emergent surgery in the setting of decompensated cirrhosis is highly morbid. We sought to determine the clinical factors associated with negative intraoperative findings at emergent laparotomy.

Methods

We performed a retrospective cohort study of consecutive inpatients with a diagnosis of cirrhosis (ICD-9 571) admitted to the Beth Israel Deaconess Medical Center (Boston, MA) who underwent emergent, nonhepatic, abdominal surgery between May 6, 2005 and September 3, 2012.

Results

Eighty-six patients with cirrhosis were included with a mean model for end-stage liver disease score of 21.3?±?7.95 and a 90-day mortality rate of 39.5 %. Twelve (16.2 %) patients had negative laparotomies. Negative intraoperative findings were independently associated with (1) paracentesis prior to a preoperative diagnosis of perforated viscus (P?=?0.006), (2) development of an indication for emergent surgery after 24 h into hospital admission for another reason (P?=?0.020), and (3) a preoperative diagnosis of bowel ischemia (P?=?0.005), with odds ratios of 10.1 (CI 1.92–66.83), 5.80 (CI 1.32–33.39), and 11.1 (CI 2.08–77.4), respectively. Free air on computed tomography (CT) imaging was found in 64.3 % (9/14) of patients who had a paracentesis within the preceding 48 h compared to 10.1 % (7/72) among patients who did not undergo a paracentesis (P?P?=?0.038). Negative laparotomy was independently predictive of in-hospital mortality (OR 4.7; P?=?0.034).

Conclusion

The possibility of a negative laparotomy is suggested by preoperative clinical factors. In particular, free air following a paracentesis does not necessarily indicate that operative intervention is required. Consideration of close observation before laparotomy in these patients is reasonable.     

Utility of MRI for diagnosing complete tears of the collateral ligaments of the metacarpophalangeal joints of the lesser digits

Background

MRI has been shown to be highly accurate in assessing collateral ligament injuries of the metacarpophalangeal joint (MPJ) of the thumb. The purpose of this study is to evaluate the accuracy of MRI for diagnosing collateral ligament tears of the MPJ of the fingers. Our hypothesis is that MRI would accurately detect complete tears of collateral ligaments of the lesser digit MPJs.

Methods

We retrospectively evaluated 22 digits in 20 patients undergoing finger MPJ collateral ligament repair. All patients had preoperative MRI scans. The findings on preoperative imaging studies were compared to the intraoperative findings.

Results

All patients had surgically confirmed complete tears of the collateral ligament in question. In 8 of 22 MRI scans (36 %), the preoperative imaging study was inaccurate. Of these eight patients, MRI was interpreted as no tear in one and a partial tear in seven. The sensitivity of MRI for diagnosing a complete tear was 64 %. In all three digits in which 3-T MRI scanning was utilized and documented, the preoperative imaging results did not correlate with the intraoperative findings.

Conclusions

Although MRI can be considered a useful adjunct to evaluating patients with collateral ligament injuries of the fingers, the sensitivity is poor and the imaging results can underestimate the extent of injury. In light of this, the emphasis for determining appropriate course of treatment remains on history and mechanism of injury, physical examination, and patient disability.     

Alterations in axial curvature of the cervical spine with a combination of rotation and extension in the conventional anterior cervical approach

Purpose

Alterations of three-dimensional cervical curvature in conventional anterior cervical approach position are not well understood. The purpose of this study was to evaluate alignment changes of the cervical spine in the position. In addition, simulated corpectomy was evaluated with regard to sufficiency of decompression and perforation of the vertebral artery canal.

Methods

Fifty patients with cervical spinal disorders participated. Cervical CT scanning was performed in the neutral and supine position (N-position) and in extension and right rotation simulating the conventional anterior approach position (ER-position). Rotation at each vertebral level was measured. With simulation of anterior corpectomy in a vertical direction with a width of 17 mm, decompression width at the posterior wall of the vertebrae and the distance from each foramen of the vertebral artery (VA) were measured.

Results

In the ER-position, the cervical spine was rotated rightward by 37.2° ± 6.2° between the occipital bone and C7. While the cervical spine was mainly rotated at C1/2, the subaxial vertebrae were also rotated by several degrees. Due to the subaxial rotation, the simulated corpectomy resulted in smaller decompression width on the left side and came closer to the VA canal on the right side.

Conclusions

In the ER-position, the degrees of right rotation of subaxial vertebrae were small but significant. Therefore, preoperative understanding of this alteration of cervical alignment is essential for performing safe and sufficient anterior corpectomy of the cervical spine.