The AESOP robot system in laparoscopic surgery: increased risk or advantage for surgeon and patient?

BACKGROUND: The aim of this study was to examine the advantages and risks of the Automated Endoscopic System for Optical Positioning (AESOP) 3000 robot system during uncomplicated laparoscopic cholecystectomies or laparoscopic hernioplasty. METHODS: In a randomized study, we examined two groups of 120 patients each with the diagnosis cholecystolithiasis respectively the unilateral inguinal hernia. We worked with the AESOP 3000, a robotic arm system that is voice-controlled by the surgeon. The subjective and objective comfort of the surgeon as well as the course and length of the operation were measured. RESULTS: The robot-assisted operations required significantly longer preparation and operation times. With regard to the necessary commands and manual camera corrections, the assistant group was favored. The same was true for the subjective evaluation of the surgical course by the surgeon. CONCLUSIONS: Our study showed that the use of AESOP during laparoscopic cholecystectomy and hernioplasty is possible in 94% of all cases. The surgeon must accept a definite loss of comfort as well as a certain loss of time against the advantage of saving on personnel.

Diagnosis and classification of inguinal hernias.

BACKGROUND: The aim of this prospective clinical study was to determine whether the presence of a hernia, its size, and its type can be established preoperatively by clinical and ultrasound, examination. METHODS: The study population comprised 220 consecutive patients referred to our department for the surgical management of an inguinal hernia. On admission, both inguinal regions were examined clinically and by ultrasound. All patients were operated on laparoscopically. RESULTS: In regard to the intraoperative findings for both inguinal regions, clinical and ultrasound examination for the diagnosis of inguinal hernia yielded a high total rate of accuracy of 93% respective 94%. However, when the same methods were used to differentiate between lateral and medial hernia, the total rate of accuracy fell to only 54% respective 62%. In the determination of inguinal hernia size, it was even lower: 50% respective 53%. CONCLUSIONS: Although a diagnosis of inguinal hernia can be established reliably by clinical and ultrasound examination, only an approximate classification is possible by these methods.

Aliphatic and aromatic carbon-fluorine bond activation with Cp*(2)ZrH(2): mechanisms of hydrodefluorination.

Cp*(2)ZrH(2) (1) (Cp* = pentamethylcyclopentadienyl) reacts with primary, secondary, and tertiary monofluorinated aliphatic hydrocarbons to give Cp*(2)ZrHF (2) and/or Cp*(2)ZrF(2) and alkane quantitatively through a radical chain mechanism. The reactivity of monofluorinated aliphatic C-F bonds decreases in the order 1 degrees > 2 degrees > 3 degrees. The rate of hydrodefluorination was also greatly reduced with -CF(2)H and -CF(3) groups attached to the hydrocarbon. An atmosphere of H(2) is required to stabilize 1 against C-H activation of the Cp*-methyl groups and subsequent dimerization under the thermal conditions employed in these reactions. Reaction of 1 with fluorobenzene cleanly forms a mixture of Cp*(2)ZrHF, benzene, and Cp*(2)Zr(C(6)H(5))F. Detailed studies indicate that radicals are not involved in this aromatic C-F activation reaction and that dual hydrodefluorination pathways are operative. In one mechanism, hydridic attack by Cp*(2)ZrH(2) on the aromatic ring and fluoride abstraction is involved. In the second mechanism, an initial ortho C-H activation occurs, followed by beta-fluoride elimination to generate a benzyne complex, which then inserts into the zirconium-hydride bond.

Can we see enough? A comparative study of film-screen vs digital radiographs in small lesions in rheumatoid arthritis.

The aim of this study was to evaluate the performance of digital radiography in the detection of early very small erosions and joint space narrowing in the hands and feet in rheumatoid arthritis. Fifty-three sets of film-screen and digital radiographs of the same hands and feet with very small and sometimes questionable lesions (possible erosions and cysts) were scored independently two times by four investigators. The percentage of lesions found in exactly the same position for each investigator was calculated. Intra-observer agreement between first and second reading in film-screen radiography was 64-76 % (mean 67 %), and in digital radiographs 60-71 % (mean 64 %). Agreement between film-screen and digital radiographs ranged from 54 to 64 % (mean 58 %) in the first reading and from 56 to 66 % (mean 62 %) in the second reading. Overall agreement between both techniques between first and second reading ranged between 62 and 73 % (mean 65 %). Digital radiography of the hands and feet can be used in patients suspected of rheumatoid arthritis and in follow-up of those patients, because small and early erosions can be seen equally well with the digital technique as compared with the conventional film-screen technique.