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D B Jones

Publications and source records attributed to D B Jones.

At least 109 records · Page 6Linked to original sources
PubMed1996

Teleproctoring laparoscopic operations with off-the-shelf technology.

Teleproctoring may be a viable approach to training surgeons in the near future. It may also be a superior form of instruction, providing for instantaneous visual and audio feed back to the participant. Conventional proctors are sometimes tempted to reach in and "help", thus infringing on the learning process of the participant. This is a problem that is averted by use of a teleproctoring system. Teleproctoring thereby challenges the proctor to expand the means by which he teaches. As new technologies mature teleproctoring may become the gold standard for teaching new surgical techniques.

Computer Systems↗
PubMed1996

Chronic acalculous cholecystitis: laparoscopic treatment.

From 1990 through 1993, we treated 36 patients with recurrent typical biliary colic but who showed no ultrasonic evidence of cholelithiasis by laparoscopic cholecystectomy. Associated symptoms included nausea (75%), bloating (56%), fatty-food intolerance (53%), vomiting (17%), weight loss (31%), bowel irregularity (28%), reflux or dyspepsia (25%), and fever (17%). Diagnostic evaluation included ultrasound (100%), upper gastrointestinal series (36%), oral cholecystogram (14%), computed tomographic scan (39%), endoscopic retrograde cholangiopancreatography (17%), upper gastrointestinal endoscopy (14%), and hepatobiliary scan (92%). Quantitative hepatobiliary scans in 33 patients revealed a low gallbladder ejection fraction (EF) of less than 35% in 29 patients (88%; mean EF = 9%), and 13 patients experienced reproducible pain after cholecystokinin provocation. All patients underwent attempted laparoscopic cholecystectomy; one case of unsuspected acute acalculous cholecystitis was converted to open laparotomy because of unclear anatomy. Gross and histological examination of the gallbladders revealed chronic inflammation (83%), cholesterolosis (31%), cholesterol crystals or small stones (17%), acute inflammation (8%), polyps (6%), and normal histology (6%); however, blind retrospective scoring of gallbladders revealed significant chronic inflammation in only 38%. In the 2 to 40 months (mean, 14 months) since operation, there have been no deaths (97% follow-up). Laparoscopic cholecystectomy relieved pain in 93% of patients with a low preoperative EF compared with 75% of patients with a normal EF (nonsignificant p value). Persistent abdominal or gastrointestinal complaints included flatulence (31%), loose stools or fecal urgency (29%), belching (29%), indigestion (20%), nausea (11%), and "typical" gallbladder pain (9%). We conclude that many patients with symptoms of biliary colic and scintigraphic evidence of biliary dyskinesia have histologic findings of chronic cholecystitis. Although laparoscopic cholecystectomy usually eliminates biliary colic, persistent nonbiliary complaints are frequent.

Adult↗
PubMed1996

Strangulated incisional hernia at trocar site.

An incisional hernia at a trocar site after laparoscopy may arise from infection, premature suture disruption, or failure to adequately reapproximate fascial wound edges. The condition is accurately diagnosed postoperatively on physical examination, and a bulge at a previous port site should immediately raise suspicion. A case is reported in which an incisional hernia strangulated soon after an elective laparoscopic inguinal herniorrhaphy in which, the fascia of the 10-mm trocar site was not closed. This report underscores the importance of meticulous closure of all abdominal port sites > 5 mm. Furthermore, early diagnosis of an incarcerated hernia may avoid the morbidity of an extensive intestinal resection.

Hernia, Inguinal↗
PubMed1996

The current management of common bile duct stones.

Choledocholithiasis is usually proven by cholangiogram during cholecystectomy, and today nearly all cholecystectomies are performed laparoscopically. Patients expect to be discharged from the hospital within 24 hours after laparoscopic surgery and return to work in 1 week. Surgeons must develop advanced laparoscopic skills to allow choledocholithiasis to be managed laparoscopically with one procedure and one anesthetic. Interventional radiologists and gastroenterologists can frequently detect and manage common duct stones that cause severe cholangitis and pancreatitis and that occur in patients too debilitated for general anesthesia. In the majority of patients, common duct stones demonstrated at laparoscopic cholecystectomy may be removed using laparoscopic transcystic techniques. Whether complicated CBD stones are optimally managed by laparoscopic choledochotomy, conversion to open common duct exploration, or left for postoperative ERC/ES is controversial and depends on the expertise of the surgeon, gastroenterologist, and wishes of the patient. Although the authors propose one algorithm for the current management of CBD stones, the superiority of the laparoscopic treatment for CBD stones is not yet proven. Multi-institutional, randomized trials comparing laparoscopic, endoscopic, and combined techniques for ductal clearance will be necessary to establish the optimal therapy of choledocholithiasis in the 1990s.

Cholangiography↗
PubMed1996

The influence of three-dimensional video systems on laparoscopic task performance.

Many laparoscopic surgeons feel constrained by the two-dimensional (2-D) view provided by video monitors. Video-eye-hand coordination is further complicated by the diminished tactile feedback blunted by elongated instruments. Video systems capable of receiving and displaying three-dimensional (3-D) images are now available for laparoscopy. First-generation 3-D systems have been marketed with the promise of significant time savings in laparoscopic procedures compared with 2-D optics. We assessed whether laparoscopic task performance was better in 2-D or 3-D among individuals with varying levels of laparoscopic experience. Five different tasks were performed in random order using both 2-D and 3-D technology by medical students (n = 10), inexperienced surgical residents (n = 10), and laparoscopic attending surgeons (n = 10). There was no significant difference in task performance between 2-D and 3-D among groups performing simple or difficult tasks, although suturing and knot-tying were performed 12% (p = 0.06) faster in 3-D by all groups. With repetition of tasks three times, the difference between the 2-D and 3-D systems was indistinguishable. Subjective assessment of the video systems by participants revealed that only 46% (p = 0.72) preferred working in three dimensions, despite 60% (p = 0.27) sensing more motor control in 3-D. Our results suggest that first-generation 3-D video systems offer no significant advantage to the novice or expert surgeon performing laparoscopic procedures. Further trials with the next generation of 3-D video systems and a larger sample size may support the trend favoring 3-D for more complex maneuvers, such as suturing and knot-typing.

Humans↗
PubMed1996

The surgical treatment of complicated GERD: a team approach.

With advances in laparoscopy, GERD is usually treatable without the need for lifelong medication. Patients may return home free from symptoms of GERD and off medications permanently. LNF has proven to be safe and effective when performed by a surgeon who is skilled in advanced laparoscopic procedures and esophageal anatomy. Utilization of the team approach is critical in managing these patients. From preoperative testing to postoperative follow-up care, nurses play key roles in the management of patients with gastroesophageal reflux.

Fundoplication↗
PubMed1995

Heterogeneous expression of Epstein-Barr virus latent proteins in endemic Burkitt's lymphoma.

Epstein-Barr virus (EBV)-infected cells may sustain three distinct forms of virus latency. In lymphoblastoid cell lines, six EBV-encoded nuclear antigens (EBNA1, 2, 3A, 3B, 3C, -LP), three latent membrane proteins (LMP1, 2A, 2B), and two nuclear RNAs (EBERs) are expressed. This form of latency, termed latency III, is also encountered in some posttransplant lymphoproliferative disorders. In EBV-positive cases of Hodgkin's disease, the EBERs, EBNA1, and the LMPs are expressed (latency II), whereas in Burkitt's lymphoma (BL) only the EBERs and EBNA1 have been detected (latency I). We have studied the expression of EBV proteins in 17 cases of EBV-positive endemic BL by immunohistology. Expression of LMP1 was seen in variable proportions of tumor cells in two cases and EBNA2 was detected in some tumor cells in three other cases. Also, the BZLF1 trans-activator protein was expressed in a few tumor cells in 6 cases, indicating entry into the lytic cycle. A phenotypic drift from latency I to latency III has been observed previously in some BL cell lines. Our results suggest that a similar phenomenon may occur in BL in vivo and indicate that the operational definition of EBV latencies is not easily applied to human tumors.

Adolescent↗
PubMed1995

Vascular networks within the stroma of human long-term bone marrow cultures.

The formation of branching and anastomosing vascular structures has been demonstrated within the stromal layers of human long-term bone marrow cultures (LTBMCs). Such organized vascular structures have not been described previously and may be of functional importance, as adherent granulocyte-predominant haemopoietic foci were more numerous in their interstices and margins than elsewhere in the stromal layers. Mature granulocytes were seen within vascular lumina in a few instances, possibly indicating an attempt to recapitulate the normal process of egress of neutrophils from bone marrow into the circulation. Immunostaining showed that the vascular structures expressed CD31, CD34, and CD105 (endoglin), which were not expressed by stromal fibroblastic cells. Collagen IV and laminin, expressed throughout the stroma, were present in increased amounts where vascular arrays were seen. In contrast, von Willebrand factor (VWF) and vascular cell adhesion molecule-1 (VCAM-1) were expressed equally by the vascular arrays and by stromal fibroblastic cells. Neither the arrays nor the general stroma expressed intercellular adhesion molecule-1 (ICAM-1), ICAM-2, ICAM-3, or endothelial leukocyte adhesion molecule-1 (ELAM-1).

Antigens, CD↗
PubMed1995

The influence of intraoperative gallbladder perforation on long-term outcome after laparoscopic cholecystectomy.

During laparoscopic cholecystectomy, gallbladder perforation with leakage of bile and/or gallstones into the abdominal cavity occurs frequently. When this occurs, our practice has been to lavage the operative field and retrieve as many gallstones as possible. We were concerned, however, that complications secondary to infection or adhesions might develop. To address this issue, our first 250 consecutive patients undergoing laparoscopic cholecystectomy were surveyed by postal questionnaire. In the 35-48 months (mean, 41 months) since operation, six patients (2.6%) died of nonbiliary causes. Of the 225 patients (90%) who completed the questionnaire, 73 (33%) suffered intraoperative gallbladder perforation. There were no late wound or intraabdominal infectious complications and no patient has required reoperation for intraabdominal sepsis or bowel obstruction. In the entire group, gastrointestinal symptoms were prevalent and included flatulence (40%), loose stools or fecal urgency (35%), belching (23%), and nausea (4%). The prevalence of these complaints was similar in patients with and without gallbladder perforation. Intraoperative gallbladder perforation during laparoscopic cholecystectomy, therefore, does not cause adverse long-term complications when accompanied by operative lavage and stone removal.

Adolescent↗
PubMed1995

Sutured or fibrin-glued laparoscopic choledochojejunostomy.

Minimally invasive techniques for choledochojejunostomy offer theoretical advantages for palliating unresectable periampullary neoplasms. Fibrin glue, a biologic adhesive containing concentrated fibrinogen, may obviate suturing and promote healing without stricture formation. We examined the technical ability to perform laparoscopic choledochojejunostomy (LCJ) and the applicability of thrombin-activated fibrin glue in an animal model of biliary obstruction. Domestic pigs underwent laparoscopic cholecystectomy and ligation of the distal bile duct. Three days later, a side-to-side LCJ was performed by intracorporeal sutured anastomosis (n = 7) or using four stay sutures and homologous fibrin glue (n = 7). Control animals underwent a similar bypass via open laparotomy (n = 7). The postoperative interval to ambulation and oral intake was recorded, and serial serum liver enzymes were measured. The animals were sacrificed at 6 weeks, and tensile strength of the anastomoses was assessed by tensometry. Liver function tests returned to normal values within 7 days following all methods of choledochojejunostomy. In the fibrin glue group, three anastomotic leaks (43%) occurred in the 1st postoperative week. At 6 weeks, all other anastomoses were intact and patent by cholangiogram, but there was moderate stenosis of two open and one fibrin-glue anastomosis. The sutured LCJ, while taking approximately 1 h longer to perform (P < 0.05), resulted in similar efficacy and more rapid recovery (P < 0.05) than open biliary-enteric bypass. Fibrin-glued LCJ was performed rapidly, but had less tensile strength (P < 0.05) and often leaked in the early post-operative interval. We conclude that while there may be a role for laser-activated solders for primary anastomosis, thrombin-activated fibrinogen cannot be advocated as the primary means of creating biliary anastomoses. Using intracorporeal suturing techniques, laparoscopic choledochojejunostomy may be performed safely.

Alanine Transaminase↗
PubMed1995

Impact of pneumoperitoneum on trocar site implantation of colon cancer in hamster model.

BACKGROUND: Numerous anecdotal reports have documented the spread of colon cancer to trocar sites after laparoscopic-assisted colectomy. We hypothesized that the pneumoperitoneum of laparoscopy potentiated tumor adherence to trocar sites. PURPOSE: This study was designed to determine the effect of CO2 pneumoperitoneum on the rate of tumor implantation at trocar sites. METHODS: Viable GW-39 human colon cancer cells were injected into the abdominal cavity of hamsters (2 x 10(6) cells/hamster). A midline laparotomy, insertion of four 5-mm trocars, injection of viable cells into the mesentery of the cecum, and free peritoneal cavity was performed in two groups: one control group (41) who did not receive a pneumoperitoneum and a comparison group (50) who underwent pneumoperitoneum for ten minutes at an insufflation pressure of 10 mmHg. Animals were killed at six weeks, and hematoxylin and eosin-stained sections of trocar wounds, midline wound, small intestine, cecum, liver, and lung were examined by a veterinary pathologist, who was blinded to operation. RESULTS: Pneumoperitoneum increased tumor implantation in the cecal mesentery and the midline incision (P < 0.05) but did not effect recurrence in the liver, lung, or jejunum. Trocar site implantation tripled with the addition of pneumoperitoneum increased implantation of pneumoperitoneum (26 vs. 75 percent) (P < 0.0001). CONCLUSION: Pneumoperitoneum increased implantation of free intra-abdominal cancer cells at wound sites on the abdominal wall or within the abdominal cavity in this animal model. The use of pneumoperitoneum during laparoscopy in patients with colon cancer should only be performed in a protocol setting to evaluate the effect of pneumoperitoneum on the treatment of cancer.

Animals↗
PubMed1995

HLA-DRB, -DQA, and -DQB polymorphism in celiac disease and enteropathy-associated T-cell lymphoma. Common features and additional risk factors for malignancy.

CD is a gluten-sensitive enteropathy, strongly associated with expression of the DQA1*0501, DQB1*0201 genotype. CD patients have an increased risk of malignancy, particularly EATCL. However, it is controversial as to whether adults with EATCL represent a subgroup of patients with CD or should be regarded as a distinct entity. To investigate the genetic relationship between CD and EATCL, HLA class II DRB1, DQA1, and DQB1 typing of peripheral blood, frozen or paraffin-embedded biopsy tissue obtained from Caucasian patients with CD (n = 91) or EATCL (n = 47) was performed by PCR-SSOP typing. Genotype frequencies were compared with those observed in 151 unrelated control individuals. A total of 83 (91%) of 91 CD patients were of DQA1*0501, DQB1*0201 genotype (pc < 10(-6), RR = 522.2), compared with 40 (93%) of 43 EATCL patients (pc < 10(-6), RR = 44.2) with amplifiable DNA versus 35 (23%) of 151 controls. DRB1*03 frequencies were also elevated in both patient groups (79 of 91 in CD [87%; pc < 10(-6), RR = 24.5] and 38 of 40 in EATCL [95%; pc < 10(-6), RR = 70.7]) compared with controls (32 of 151, 21%). These results confirm previous studies of HLA associations in CD and also suggest that EATCL arises in individuals with the DQA1*0501, DQB1*0201 CD-predisposing genotype. However, the frequency of DRB1*03,04 heterozygotes was significantly increased in the EATCL group (16 of 40, 40%) compared with both control individuals (3 of 151, 2%; pc < 10(-6), RR = 32.9) and uncomplicated CD patients (6 of 91, 7%; pc = 0.04, RR = 9.4).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Corneal lipidosis in patients with the acquired immunodeficiency syndrome.

PURPOSE: Certain drugs bind to anionic phospholipids of lysosomal membranes and produce progressive intracellular accumulation of lamellar inclusions. We studied two patients treated for opportunistic infections associated with the acquired immunodeficiency syndrome (AIDS), who developed bilateral ocular surface changes suggestive of drug-induced corneal lipidosis. METHODS: Two patients with AIDS had translucent vacuoles within the corneal epithelium and mild conjunctival hyperemia. Because the differential diagnosis included microsporidial keratoconjunctivitis, biopsies of the ocular surface were performed for histopathologic analysis. RESULTS: Transmission electron microscopy of corneal epithelial debridement and conjunctival biopsy specimens showed intracellular, electron-dense lipoidal bodies and multilaminated lysosomal inclusions suggestive of a drug-induced lipidosis. Both patients also had tubuloreticular inclusions in conjunctival capillary endothelial cells. The ocular surface changes resolved within one to three months after dosage reduction or discontinuation of systemic ganciclovir and acyclovir. CONCLUSIONS: Drug-induced phospholipidosis is a cause of punctate corneal epitheliopathy during AIDS, but the responsible agent remains to be identified.

AIDS-Related Opportunistic Infections↗
PubMed1995

Results of a change to routine fluorocholangiography during laparoscopic cholecystectomy.

BACKGROUND: Early in our experience with laparoscopic cholecystectomy (LC), intraoperative cholangiography (IOC) was performed selectively with static imaging techniques. We subsequently changed to routine digital fluorocholangiography (FIOC) and evaluated the results of this strategy. METHODS: In a consecutive series of 356 LCs, 11 patients (3%) were converted to open cholecystectomy. In the remaining 345 patients FIOC was attempted in 336 patients (97%) and was successfully completed in 328 patients (95%). Results of IOC and outcomes were compared prospectively in patients without indications for IOC (group I, n = 185) with those with criteria for selective IOC (group 2, n = 160) and retrospectively with patients without indications for IOC undergoing static IOC (group 3, n = 56). RESULTS: Time to perform FIOC was less than for static IOC (14 +/- 1 versus 24 +/- 1 minutes, p < 0.001). Aberrant ductal anatomy was appreciated by using FIOC in 11% but affected operative management in only 3% of patients. Choledocholithiasis was detected in 23 patients (7%) undergoing FIOC; only two of these patients with stones were in Group 1. Duct stones discovered by IOC were cleared laparoscopically in 89% of those attempted (73% of all patients). Neither morbidity nor duct injury caused by FIOC was noted. CONCLUSIONS: FIOC is much more rapid to perform than static IOC. Digital fluoroscopy is accurate and safe and permits rapid evaluation and management of bile duct stones. Selective use of FIOC efficiently assesses the common duct in the era of LC.

Cholangiography↗
PubMed1995

Immunohistochemical characterization of intact stromal layers in long-term cultures of human bone marrow.

We have performed an immunohistochemical study of intact adherent layers of human long-term bone marrow cultures (hLTBMC) in order to characterize the cell types present. Our panel of antibodies was selected to demonstrate various mesenchymal and haemopoietically derived cell types and to assess the presence of molecules of potential importance as adhesive ligands between haemopoietic cells and stroma. Subpopulations of fibroblasts and macrophages were identified which differed in immunophenotype. We were able to demonstrate modulation of fibroblast and extra-cellular matrix immunophenotypes between 2 and 12 weeks in culture. Stromal cells and matrix expressed a wide variety of antigens of potential importance in haemopoietic cell adhesion, but no ICAM-1, 2 or 3 could be demonstrated to correspond to the strong LFA-1 expression seen in haemopoietic precursor cells. No localization of antigen expression by stromal elements was found to account for the formation of haemopoietic foci at particular sites. However, granulocyte-predominant foci preferentially occupied the interstices and margins of structures which appeared to be vascular arrays.

Bone Marrow Cells↗
PubMed1995

Sites of M-CSF messenger RNA production in bone marrow trephine biopsy specimens and long term cultures demonstrated by nonisotopic in situ hybridisation.

Aim-To develop methods of messenger RNA (mRNA) in situ hybridisation (ISH) for use with routinely processed bone marrow trephine biopsy specimens, decalcified using formic acid, and long term cultures in order to demonstrate sites of synthesis of mRNA encoding monocyte colony stimulating factor (M-CSF).Methods-Biotinylated oligonucleotide probes, directed against target sequences within M-CSF mRNA, were hybridised with sections from bone marrow trephine biopsy specimens and detected using Streptavidin-biotin alkaline phosphatase complex formation. Validation of results included demonstration of total mRNA and unrelated mRNA species in adjacent sections, with appropriate negative controls. Minor technical modifications were required to perform ISH with long term bone marrow cultures.Results-M-CSF mRNA was demonstrated successfully in trephine biopsy specimens and long term cultures. Biopsy specimens varied in their requirement for predigestion with proteinase K and in the strength of the final reaction product, presumably due to variation in fixation. M-CSF mRNA was present in myelocytes and promonocytes. No stromal production of M-CSF mRNA was detected in biopsy specimens. ISH using long term bone marrow cultures confirmed production of M-CSF mRNA by developing monocytes and macrophages. Weak M-CSF mRNA expression was also seen in stromal fibroblasts.Conclusions-ISH can be performed successfully with formic acid decalcified bone marrow trephine biopsy specimens and long term cultures. The presence of M-CSF mRNA in myelomonocytic cells suggests that an autocrine mechanism contributes to monocyte differentiation. The absence of detectable M-CSF mRNA in biopsy stroma and its presence in stromal fibroblasts within bone marrow cultures probably reflects reduced sensitivity of ISH following tissue fixation and processing.

Journal Article↗