Experimental ridge augmentation with porous hydroxyapatite implants

A new hydroxyapatite ceramic implant material for restoration of atrophic edentulous ridges was tested in a canine animal model. The structure of this material is unique, in that it is produced from the skeleton of a coral, and in that it is penetrated by a uniform network of interconnected pores. Results indicate that bone penetrates its structure to a greater degree than had been observed with similar implants constructed of different materials. Implant insertion through a simple surgical technique involving minimal morbidity is a viable method of placement.     

Do consensus indications for resection in branch duct intraductal papillary mucinous neoplasm predict malignancy? A study of 147 patients

BACKGROUND AND AIMS: Recent consensus guidelines suggest that presence of > or =1 of the following is an indication for resection (IR) of branch duct intraductal papillary mucinous neoplasm (IPMN-Br): cyst-related symptoms, main pancreatic duct diameter > or =10 mm, cyst size > or =30 mm, intramural nodules, or cyst fluid cytology suspicious/positive for malignancy. Among a cohort of patients with IPMN-Br we determined if the consensus IR (CIR), presence of multifocal IPMN-Br, or growth of cyst size on follow-up predict malignancy. METHODS: We identified 147 patients with IPMN-Br of whom 66 underwent surgical resection at diagnosis and 81 were followed conservatively, of whom 11 were resected during follow-up. Clinical, imaging, histological, and cyst fluid characteristics from all 147 patients with IPMN-Br were obtained from clinical records and/or by contacting the patients. In all cases, presence of CIR at baseline and during follow-up (N = 66), presence of multifocal cysts (N = 57), and increase in cyst size (N = 38) were noted. RESULTS: Among the 77 resected IPMN-Brs, at initial evaluation 61 had at least one CIR and 16 had none. Malignancy was present in 9/61 (15%) with CIR and 0/16 without IR (P= 0.1). When presence of any one of the CIR was taken as an indicator of malignancy, the CIR had a sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 23%, 14%, and 100%, respectively. Prevalence of malignancy in those with single versus multifocal IPMN-Br was similar (13%vs 11%). No patient has developed malignancy after a median follow-up of 15 months. So far, none of the 38 patients with increase in cyst size on follow-up has developed malignancy related symptoms. CONCLUSIONS: Suggested consensus indications for resection identify all patients with malignancy; however, their specificity is low. In the short term it would be safe to follow patients without these features.     

Endoscopic retrograde cholangiopancreatography catheter and accessory exchange using a short hydrophilic guide wire: a prospective study

BACKGROUND AND STUDY AIMS: Although hydrophilic guide wires can be used to facilitate stricture cannulation during endoscopic retrograde cholangiopancreatography (ERCP), some endoscopists avoid using them because of concerns about wire loss during exchange. There are no data available on the outcomes of using a short hydrophilic guide wire during ERCP. The aim of this study was to assess the outcomes of therapeutic ERCP procedures in which a short, completely hydrophilic guide wire was used exclusively. PATIENTS AND METHODS: A total of 100 patients undergoing ERCP were studied prospectively. A 0.035-inch, 260-cm long, angled-tip hydrophilic wire (Terumo Glidewire) was used initially. Hydraulic catheter exchange was performed as follows: during catheter withdrawal the assistant advanced all the available wire into the catheter; a 12-ml syringe was then attached to the catheter and water was flushed under pressure to "float the wire" and maintain its position during catheter removal. Variables evaluated included exchange times and wire loss rates. RESULTS: A total of 223 catheter exchanges were performed, 132 (59%) using the Olympus V-Scope (which held the wire in 62% of cases): 15% of exchanges were with catheters/accessories designed for short-wire use (Boston Scientific Rapid Exchange Biliary System or Rx System), and 85% were with a variety of standard-length accessories. Overall, the mean exchange time was 26 seconds (range 6 - 90 seconds, standard deviation 12 seconds). The mean exchange time was faster with the V-Scope and with non-Rx-System accessories. Wire loss occurred in 5 % of all exchanges. Desired ductal/stricture access was achieved in all the patients. CONCLUSIONS: Exchange of short hydrophilic wires is quick and reliable. The Olympus V-Scope is able to hold the wire in some cases. Monorail-type devices and accessories slow catheter exchange down slightly because hydraulic exchange cannot be performed using these systems.     

EUS diagnosis of vascular invasion in pancreatic cancer: surgical and histologic correlates

BACKGROUND: Endoscopic ultrasound (EUS) has been compared to intraoperative surgical palpation for diagnosis of vascular invasion by pancreatic cancer. This study compares EUS with vascular resection and histologic evidence of vascular invasion in resected pancreatic masses. METHODS: All patients with solid pancreatic masses who underwent both preoperative EUS and surgery at 1 hospital over a 7 year period were identified. The relationship of pancreatic masses to adjacent vessels was prospectively assessed by EUS. EUS findings were compared to surgical and pathology gold standards. "Vascular adherence" was defined as tumor adherence requiring vascular resection during surgery, and "vascular invasion" as histologic invasion of vessel wall by tumor. RESULTS: 30 of 68 patients were resectable. Among these 30, vascular adherence was present in 8, including 18% of patients with an intact echoplane between tumor and adjacent vessels at EUS, 29% of those with loss of echoplane alone, and 50% of those with additional EUS features of vascular involvement. Vascular invasion was present in 4, including 12% of patients with an intact echoplane, 0% of those with loss of echoplane alone, and 33% of those with additional EUS features. Sensitivity, specificity, PPV, and NPV of EUS were 63%, 64%, 43% and 80% for vascular adherence and 50% 58%, 28% and 82% for vascular invasion. NPV rose to 90% for vascular adherence if only the portal confluence vessels were considered. CONCLUSIONS: EUS has poor sensitivity, specificity, and positive predictive value for diagnosis of venous involvement by pancreatic cancer.