Subsequent Adenomas of Ileal Pouch and Anorectal Segment after Prophylactic Surgery for Familial Adenomatous Polyposis.

Familial adenomatous polyposis (FAP) is an autosomally dominant disease characterized by the early development of colorectal adenomas and carcinoma in untreated patients. Patients with FAP may develop rectal cancer at their initial presentation (primary) or after prophylactic surgery (secondary). Controversies exist regarding which surgical procedure represents the best first-line treatment. The options for FAP are ileorectal anastomosis (IRA) or a restorative proctocolectomy (RPC) with either a handsewn or a stapled ileal pouch-anal anastomosis (IPAA), with or without mucosectomy. The purpose of these surgeries is to stop progression to an adenoma-cancer sequence by eradicating the colon, a disease prone organ. Unfortunately, these surgical procedures, which excise the entire colon and rectum while maintaining transanal fecal continence, do not guarantee that patients still won't develop adenomas. Based on the available literature, we therefore reviewed reported incidences of pouch-related adenomas that occurred post prophylactic surgery for FAP. The review consists of a collection of case, descriptive, prospective and retrospective reports. OBJECTIVES: To provide available data on the natural history of subsequent adenomas after prophylactic surgery (by type) for FAP. METHODS: A review was conducted of existing case, descriptive, prospective and retrospective reports for patients undergoing prophylactic surgery for FAP (1975 - August, 2013). In each case, the adenomas were clearly diagnosed in one of the following: the ileal pouch mucosa (above the ileorectal anastomosis), within the anorectal segment (ARS) below the ileorectal anastomosis, or in the afferent ileal loop. RESULTS: A total of 515 (36%) patients with pouch-related adenomas have been reported. Two hundred and eleven (211) patients had adenomas in the ileal pouch mucosa, 295 had them in the ARS and in 9 were in the afferent ileal loop. Patients with pouch adenomas without dysplasia or cancer were either endoscopically polypectomized or were treated with a coagulation modality using either a Nd:Yag laser or argon plasma coagulation (as indicated). Patients with dysplastic pouch adenomas or pouch adenomas with cancer had their pouch excised (pouchectomy). CONCLUSION: In patients with FAP treated with IRA or RPC with IPAA, the formation of adenomas in the pouch-body mucosa or ARS/anastomosis and in the afferent ileal loop is apparent. Because of risks for adenoma recurrence, a life time endoscopic pouch-surveillance is warranted.

Carcinoid tumors are 15 times more common in patients with Crohn's disease.

BACKGROUND: The coexistence of intestinal neoplasms with Crohn's disease (CD) has been reported, but the evidence of an increased risk of carcinoid tumor with Crohn's disease has been mixed. We present 4 patients with CD with associated carcinoid tumor. METHODS: The charts of 111 patients with CD who had undergone resection between June 2001 and March 2005 were reviewed. The number of incidental carcinoid tumors in patients who underwent an appendectomy was used as a control. RESULTS: Four cases of carcinoid tumor discovered in patients at resection for CD were identified. None had metastatic disease or carcinoid syndrome. These included 1 cecal (1 mm), 2 appendiceal (3 and 7 mm), and 1 transverse colon (7 mm) carcinoid tumors. None of the carcinoid tumors were identified in regions of active Crohn's disease. The incidence of carcinoid tumor in patients with Crohn's disease was 4 of 111 (3.6%). In comparison, 3 of 1199 patients (0.25%) who had appendectomies were identified as having appendiceal carcinoid tumor. Crohn's disease was associated with an increased incidence of carcinoid tumor; OR 14.9 (95% CI 2.5-102.5), P<0.0001. CONCLUSIONS: There was a significantly increased incidence of carcinoid tumor in our Crohn's patients compared to the control patients. None of the carcinoid tumors developed in areas of Crohn's disease. This suggests that the development of carcinoid tumors may be secondary to distant proinflammatory mediators, rather than a local inflammatory effect from adjacent Crohn's disease. Patients with CD may be at increased risk of developing a carcinoid tumor.

A prototype ultrasound-guided laparoscopic radiofrequency ablation system.

BACKGROUND: Advanced laparoscopic procedures, particularly laparoscopic liver resection and ablation, may benefit from image-guided surgery techniques that involve interactive three-dimensional imaging and instrument tracking. METHODS: A prototype system for laparoscopic ultrasound-guided radiofrequency ablation was designed and implemented. This system uses an infrared camera to track instruments and runs on a personal computer. Features of the system include spatially registered ultrasound visualization, volume reconstruction, and interactive targeting. Targeting of accuracy studies was performed by directing a tracked needle to a phantom target. RESULTS: Ultrasound data collection and volume reconstruction can be achieved within minutes and interactively reviewed by the surgeon. Early results with phantom experiments demonstrate a targeting accuracy of 5 to 10 mm. CONCLUSIONS: These results support the further development of this and similar image-guided surgery systems for specific laparoscopic procedures. Eventually, rigorous clinical evaluation will be necessary to prove their value.

Ultrasound-to-computer-tomography registration for image-guided laparoscopic liver surgery.

BACKGROUND: The application of image-guided surgery (IGS) to laparoscopic liver resection and ablation is currently limited, but it would assist in intraoperative decision making regarding oncologic margins, ablation probe placement, and ablation tracking. METHODS: Eight spherical surface targets on a liver phantom were imaged with an optically tracked laparoscopic ultrasound (US) probe. Ten US images of each target were registered to computer tomography (CT) images of the phantoms and then mapped to the CT scans. Accuracy of the registration was assessed by comparing the distance between the predicted target location and the position obtained directly from CT. RESULTS: The average localization error was 5.3 mm. The errors resulted primarily from inaccurate US probe tracking but were otherwise insensitive to the variability that arises from manually identifying targets in US and CT images. CONCLUSIONS: The results obtained for US-to-CT registration in a phantom model suggest that further investigations into its clinical use are warranted and that other IGS technologies could be applied to laparoscopic liver surgery as well.

The impact of a laparoscopic colorectal surgeon on the laparoscopic colectomy experience of a single academic center.

BACKGROUND: The objective of this study was to evaluate the impact of a laparoscopic colorectal surgeon (LCRS) on the laparoscopic colectomy experience of a single academic center. METHODS: We performed a retrospective review of case complexity, patient characteristics, operative and preparation time, and trends over time for the LCRS compared to two veteran laparoscopic surgeons (VLS). RESULTS: The LCRS performed 48 of the procedures (83%) and the VLS 10 (17%) for a total of 58 laparoscopic colon cases. The LCRS handled a greater number of complex cases (p = 0.07). For less complex cases, overall operative time differed for the two groups (LCRS = 220 +/- 11 vs VLS = 152 +/- 15 min, p = 0.004). Overall hospital stay was 4.8 +/- 0.6 days (range, 2-33). Minor complications occurred in 12 cases (21%); major complications in occurred in seven cases (12%). Among procedures performed by the LCRS, comparison of the first 24 cases to the second 24 demonstrated that operative and preparation time decreased in the second cohort (all p < 0.05). CONCLUSION: The addition of an LCRS had a significant impact on this center's experience with laparoscopic colectomies in terms of both volume and case complexity.

Bile duct injury following laparoscopic cholecystectomy: a cause for continued concern.

Previous reports suggest that bile duct injuries sustained during laparoscopic cholecystectomy (lap chole) are frequently severe and related to cautery and high clip ligation. We performed a review of patients who sustained bile duct injury from lap chole since 1990 and assessed time to injury recognition, time to referral, Bismuth classification, initial and subsequent repairs, rate of recurrence, and length of follow-up. Seventy-four patients [median age 44 years, 58 of 74 female (78%)] were referred with a bile duct injury after lap chole. The level of injury was evenly divided between the bile duct bifurcation and the common hepatic duct: Bismuth III, IV, and V (40 of 74, 54%) versus Bismuth I and II (34 of 74, 46%). Concomitant hepatic arterial injury was identified in nine (12%) patients. Patients referred early after bile duct injury and requiring operative intervention underwent hepaticojejunostomy at a median of 2 days after referral. After surgical reconstruction at our center there has been an overall success rate of 89 per cent with no need for reintervention. Six (10%) of these patients have required one additional balloon dilatation at a mean follow-up of >24 months. One (2%) patient underwent biliary-enteric revision in follow-up. In patients with bile duct injury, stricture repair without delay was successful in the majority of patients treated in this series. Only one of 64 patients reconstructed at our center has required reoperation; six others have required a single balloon dilatation with subsequent good or excellent results. The majority of patients treated with operative repair at an experienced center can expect good long-term results with rare need for reintervention.

Registration of physical space to laparoscopic image space for use in minimally invasive hepatic surgery.

While laparoscopes are used for numerous minimally invasive (MI) procedures, MI liver resection and ablative surgery is infrequently performed. The paucity of cases is due to the restriction of the field of view by the laparoscope and the difficulty in determining tumor location and margins under video guidance. By merging MI surgery with interactive, image-guided surgery (IIGS), we hope to overcome localization difficulties present in laparoscopic liver procedures. One key component of any IIGS system is the development of accurate registration techniques to map image space to physical or patient space. This manuscript focuses on the accuracy and analysis of the direct linear transformation (DLT) method to register physical space with laparoscopic image space on both distorted and distortion-corrected video images. Experiments were conducted on a liver-sized plastic phantom affixed with 20 markers at various depths. After localizing the points in both physical and laparoscopic image space, registration accuracy was assessed for different combinations and numbers of control points (n) to determine the quantity necessary to develop a robust registration matrix. For n = 11, average target registration error (TRE) was 0.70 +/- 0.20 mm. We also studied the effects of distortion correction on registration accuracy. For the particular distortion correction method and laparoscope used in our experiments, there was no statistical significance between physical to image registration error for distorted and corrected images. In cases where a minimum number of control points (n = 6) are acquired, the DLT is often not stable and the mathematical process can lead to high TRE values. Mathematical filters developed through the analysis of the DLT were used to prospectively eliminate outlier cases where the TRE was high. For n = 6, prefilter average TRE was 17.4 +/- 153 mm for all trials; when the filters were applied, average TRE decreased to 1.64 +/- 1.10 mm for the remaining trials.

Technical advances toward interactive image-guided laparoscopic surgery.

BACKGROUND: Laparoscopic surgery uses real-time video to display the operative field. Interactive image-guided surgery (IIGS) is the real-time display of surgical instrument location on corresponding computed tomography (CT) scans or magnetic resonance images (MRI). We hypothesize that laparoscopic IIGS technologies can be combined to offer guidance for general surgery and, in particular, hepatic procedures. Tumor information determined from CT imaging can be overlayed onto laparoscopic video imaging to allow more precise resection or ablation. METHODS: We mapped three-dimensional (3D) physical space to 2D laparoscopic video space using a common mathematical formula. Inherent distortions present in the video images were quantified and then corrected to determine their effect on this 3D to 2D mapping. RESULTS: Errors in mapping 3D physical space to 2D video image space ranged from 0.65 to 2.75 mm. CONCLUSIONS: Laparoscopic IIGS allows accurate (<3.0 mm) confirmation of 3D physical space points on video images. This in combination with accurately tracked instruments and an appropriate display may facilitate enhanced image guidance during laparoscopy.

Surface registration for use in interactive, image-guided liver surgery.

OBJECTIVE: Liver surgery is difficult because of limited external landmarks, significant vascularity, and inexact definition of intra-hepatic anatomy. Intra-operative ultrasound (IOUS) has been widely used in an attempt to overcome these difficulties, but is limited by its two-dimensional nature, inter-user variability, and image obliteration with ablative or resectional techniques. Because the anatomy of the liver and intra-operative removal of hepatic ligaments make intrinsic or extrinsic point-based registration impractical, we have implemented a surface registration technique to map physical space into CT image space, and have tested the accuracy of this method on an anatomical liver phantom with embedded tumor targets. MATERIALS AND METHODS: Liver phantoms were created from anatomically correct molds with "tumors" embedded within the substance of the liver. Helical CT scans were performed with 3-mm slices. Using an optically active position sensor, the surface of the liver was digitized according to anatomical segments. A surface registration was performed and RMS errors of the locations of internal tumors are presented as verification. An initial point-based marker registration was performed and considered the "gold standard" for error measurement. RESULTS: Errors for surface registration were 2.9 mm for the entire surface and 2.8 mm for embedded targets. CONCLUSION: This is an initial study considering the use of surface registration for the purpose of physical-to-image registration in the area of liver surgery.

Acute pancreatitis after cardiac transplantation and other cardiac procedures: case-control analysis in 24,631 patients.

Previous series have identified an increased risk of developing acute postoperative pancreatitis in heart transplant recipients and other cardiac surgical patients, and some suggest that mortality is significantly increased when pancreatitis occurs in the transplant setting. We conducted a retrospective case-control analysis of adult patients undergoing orthotopic heart transplant or other cardiac procedures from April 1985 through June 1996 at our medical center. Specific risk factors for outcome were assessed including low cardiac output, intra-aortic balloon pump usage, exogenous calcium repletion, immunosuppression, cytomegalovirus infection, cholelithiasis, prior pancreatitis, and Acute Physiology and Chronic Health Evaluation (APACHE) II scores. There was a 30-fold increase in the incidence of pancreatitis in the heart transplant group [12 of 394 (3%) vs 27 of 24,237 (0.1%); P < 0.01]. Compared with the nontransplant cardiopulmonary bypass patients, the transplant patients experienced a statistically significant increased incidence of immunosuppression and three or more risk factors. Transplant patients with pancreatitis demonstrated a significant increase in APACHE II scores and the incidence of three or more risk factors compared with their transplant control group. Patients undergoing nontransplant cardiac procedures and developing pancreatitis had significantly increased cross-clamp times, incidence of low cardiac output, APACHE II scores, and incidence of three or more risk factors compared with their nontransplant cohort. In conclusion, there is a significant increase in the incidence of pancreatitis after orthotopic heart transplant compared with other cardiac procedures. Analysis demonstrates the additive effect of multiple individual risk factors. Immunosuppression confers significant additional risk for pancreatitis in the orthotopic heart transplant patient.

Image-guided surgery: preliminary feasibility studies of frameless stereotactic liver surgery.

BACKGROUND: Liver surgery can be difficult because there are few external landmarks defining hepatic anatomy and because the liver has significant vascularity. Although preoperative tomographic imaging (computed tomography or magnetic resonance imaging) provides essential anatomical information for operative planning, at present it cannot be used actively for precise localization during surgery. Interactive image-guided surgery involves the simultaneous real-time display of intraoperative instrument location on preoperative images (computed or positron-emission tomography or magnetic resonance imaging). Interactive image-guided surgery has been described for tumor localization in the brain (frameless stereotactic surgery) and allows for interactive use of preoperative images during resections or biopsies. HYPOTHESIS: The application of interactive image-guided surgery (IIGS) is feasible for hepatic procedures from a biomedical engineering standpoint. METHODS: We developed an interactive image-guided surgery system for liver surgery and tested a porcine liver model for tracking liver motion during insufflation; liver motion during respiration in open procedures in patients undergoing hepatic resection; and tracking accuracy of general surgical instruments, including a laparoscope and an ultrasound probe. RESULTS: Liver motion due to insufflation can be quantified; average motion was 2.5+/-1.4 mm. Average total liver motion secondary to respiration in patients was 10.8 +/-2.5 mm. Instruments of varying lengths, including a laparoscope, can be tracked to accuracies ranging from 1.4 to 2.1 mm within a 27-m3 (3 X 3 X 3-m) space. CONCLUSION: Interactive image-guided surgery appears to be feasible for open and laparoscopic hepatic procedures and may enhance future operative localization.

Surgical clips: a cause of late recurrent gallstones.

The formation of gallstones around surgical clips after cholecystectomy is a rare complication, with only seven reported cases in the English literature since its initial description in 1979. Three other cases report clip migration into the common bile duct and obstruction. We report a recent experience with "clip cholelithiasis." A 78-year-old female, 16 years following cholecystectomy, presented with a several-month history of colicky abdominal pain worsened by meals, and a 1 week history of jaundice, anorexia, nausea, and vomiting. An abdominal ultrasound demonstrated dilatation of the biliary tree without visible choledocholithiasis. Endoscopic retrograde cholangiopancreatography demonstrated a 1.5-cm radiolucent stone in the common bile duct containing a central surgical clip. She was successfully treated with endoscopic sphincterotomy and stone retrieval. The first report of clip cholelithiasis occurred in 1979. Six additional cases have been reported as well as three cases of clip migration without stone formation into the common bile duct. The incidence of clip cholelithiasis may increase in frequency with the increased use of metallic clips during laparoscopic cholecystectomy. The occurrence of cholelithiasis around inert metals is rare and may be prevented using absorbable clips; however, stone formation is also reported around absorbable materials.

Laparoscopic cholecystectomy in children with sickle cell disease.

Since 1991, laparoscopic cholecystectomy has been utilized in children with sickle cell disease, predominantly because of the decreased pain and shorter hospitalization. We believe that outpatient laparoscopic cholecystectomy or even a 24 hour hospitalization is not indicated in the patient with sickle cell disease. Perioperative complications include bleeding diathesis, vaso-occlusive phenomena, and delayed hemolytic transfusion reactions, although clotting parameters can be normal.

Thoracic empyema in a patient with acute appendicitis: a rare association.

Thoracic empyema and appendicitis rarely are concomitant. This is the first report of ultrasonography and computed tomography being used preoperatively to establish the diagnosis of ruptured appendicitis in a child with thoracic empyema. The perforated appendicitis was identified after gastrointestinal flora were cultured from the thoracostomy drainage of the empyema.