Olav Istre - Academia.edu (original) (raw)
Papers by Olav Istre
Obstetrical & Gynecological Survey, Aug 1, 1989
This study's aim was to determine whether the inclusion of superficial perineal structures in a f... more This study's aim was to determine whether the inclusion of superficial perineal structures in a finite-element simulation of vaginal delivery impacts the pubovisceral muscle and perineal body, two common sites of birth-related injury. The hypothesis, inferred from prevailing literature, was that these structures would have minimal influence (differences less than +10%). Two models were made using the Visible Human Project's female cadaver to create a rigid, fixed pelvis, musculature held by spring attachments to that pelvis, and a rigid, ellipsoidal fetal head prescribed with an inferior displacement to simulate delivery. Injury site stretch ratios and fetal head and perineal body displacements and angles of progression were compared between the Omitted Model (which excluded the superficial perineal structures as is common practice) and the Included Model (which included them). Included Model stretch ratios were þ107%, 29.84% and 214.6% compared to Omitted Model perineal body and right and left pubovisceral muscles, respectively. Included Model peak perineal body inferior displacement was þ72.5% greater while similar anterior-posterior displacements took longer to reach. These results refute our hypothesis, suggesting superficial perineal structures impact simulations of vaginal delivery by inhibiting perineal body anterior-posterior displacement, which stretches and inferiorly displaces the perineal body.
Journal of Minimally Invasive Gynecology, 2013
Bjog: An International Journal Of Obstetrics And Gynaecology, May 16, 2007
Objective To compare the impact of 1000 micrograms of self-administered vaginal misoprostol versu... more Objective To compare the impact of 1000 micrograms of self-administered vaginal misoprostol versus self-administered vaginal placebo at home on preoperative cervical ripening in both premenopausal and postmenopausal women before operative hysteroscopy. Design Two separate but identical parallel, randomised, double-blind, placebo-controlled sequential trials, one in premenopausal women and one in postmenopausal women. The boundaries for the sequential trials were calculated on the primary outcomes of a difference of cervical dilatation ‡1 mm, with the assumption of a type 1 error of 0.05 and a power of 0.95. Setting Norwegian university teaching hospital. Sample Eighty-six women referred to outpatient operative hysteroscopy. Methods The women were randomised to either 1000 micrograms of self-administered vaginal misoprostol or self-administered vaginal placebo the evening before outpatient operative hysteroscopy.
Ultrasound in Obstetrics and Gynecology, 2008
similar to those on MRI with the ''sausage in a tube'' appearance. On CT, findings were interpret... more similar to those on MRI with the ''sausage in a tube'' appearance. On CT, findings were interpreted as metastatic ovarian cancer in 2 women. Path showed poorly differentiated adenocarcinoma in 9/10, mixed müllerian tumor in 1/10; invasion of adjacent uterus, ovary, cul de sac, mesentery/peritoneum or bowel was present in 6/10 women. Conclusions: Primary tubal carcinoma usually presents at an advanced stage. In our series a prospective diagnosis was not made on CT or US. However, the correct diagnosis was suggested based on MRI in our small sample with similar findings in all cases: a solid enhancing adnexal mass partly or completely located within a dilated fallopian tube.
Acta Obstetricia et Gynecologica Scandinavica, 2001
Journal of Vascular and Interventional Radiology, Oct 1, 2009
To compare long-term symptom recurrence and 6-month magnetic resonance (MR) imaging results after... more To compare long-term symptom recurrence and 6-month magnetic resonance (MR) imaging results after two different treatments for uterine leiomyomas. Sixty-six women with uterine leiomyomas were randomized to undergo uterine artery embolization (UAE) or laparoscopic bilateral occlusion of uterine arteries. Contrast-enhanced MR imaging was performed before treatment and after 6 months. Fifty-eight patients received treatment. Median follow-up time was 48 months (range, 8-73 months). Clinical failure and symptom recurrence occurred in 14 patients after laparoscopy (48%) and in five after UAE (17%; P = .02, log-rank test). Hysterectomy was performed in two patients after UAE (7%) and in eight after laparoscopy (28%; P = .041). Six-month MR imaging results were available for 26 patients treated with UAE and 22 treated with laparoscopy. The mean uterine volume was reduced by 51% (range, 16%-86%) after UAE treatment, compared with 33% (range, 6%-77%) after laparoscopy (P = .001). Complete leiomyoma infarction was seen in all 26 patients in the UAE group and in only five patients in the laparoscopy group (P < .001). Eleven patients experienced symptom recurrence later than 6 months. Uterine volume reduction at 6 months was 24% in this group, compared with 48% in the 37 patients with no recurrence (P = .004). Incomplete infarction of leiomyomas was seen in eight of the 11 cases of recurrence (73%) versus nine of 37 cases without recurrence (24%; P = .009). Recurrence rate was significantly lower after UAE than after laparoscopic treatment. Larger volume reduction and more complete devascularization of leiomyomas were found after UAE treatment and among patients with no recurrence.
Journal of The American Association of Gynecologic Laparoscopists, Aug 1, 2001
Gynaecological Endoscopy, Nov 14, 2003
Objective To evaluate the diagnostic accuracy of Pipelle endometrial biopsies before surgical tre... more Objective To evaluate the diagnostic accuracy of Pipelle endometrial biopsies before surgical treatment of uterine bleeding disorders. Design Retrospective analysis. Setting County Hospital unit specializing in operative hysteroscopy. Interventions Routine outpatient endometrium biopsies were taken from 628 patients because of uterine bleeding disorders. Of these patients, 249 underwent transcervical resection of the endometrium (TCRE) and 75 had a hysterectomy within 6 months. Results Comparing the two subgroups ‘malignant’ and ‘benign’, the positive predictive value for endometrial malignancy was 100% (95% CI, 73.5–100). Insufficient tissue was obtained in five cases (1.5%); in three there were submucous fibroids, in one sampling took place after TCRE, and one patient had atrophic endometrium. Conclusion Adequate preoperative histological assessment of the endometrium is feasible with Pipelle biopsies, and they are highly accurate in detecting endometrial malignancy.
Acta Obstetricia et Gynecologica Scandinavica, Jul 1, 2001
Objective. To evaluate the diagnostic accuracy of transvaginal ultrasonography, sonohysterography... more Objective. To evaluate the diagnostic accuracy of transvaginal ultrasonography, sonohysterography and hysteroscopy in patients presenting with abnormal uterine bleeding. Design. Prospective, blind, comparative study. Setting. Outpatient clinic and day surgery unit of a district hospital specializing in operative hysteroscopy. Patients. One hundred consecutive patients referred with abnormal uterine bleeding (AUB). Interventions. Transvaginal ultrasonography and sonohysterography were performed in the outpatient clinic. Within 1 week, all patients underwent operative hysteroscopy. Main outcome measures. All diagnoses established by transvaginal ultrasonography, and sonohysterography were compared to the appearance of the cavity using hysteroscopy as well as the histological diagnosis from removed tissues. Results. In 88 patients information suitable for analysis was obtained by all methods. The detection rate of focal intrauterine pathology using sonohysterography was (94.1%), but was significantly lower with transvaginal ultrasonography (23.5%). In about 75% of all cases none of the methods used was able to correctly detect endometrial hyperplasia. Conclusions. Sonohysterography was significantly better than transvaginal ultrasonography in detecting focal intrauterine pathology. Visual examination at operative hysteroscopy yielded no additional information to the detection or exclusion of focal lesions than was obtained at outpatient sonohysterography. All methods performed equally in assessing endometrial pathology. We conclude that sonohysterography may replace diagnostic hysteroscopy in many patients with AUB.
Endometrial carcinoma is the most common gynecologic cancer in developed countries. The overall 5... more Endometrial carcinoma is the most common gynecologic cancer in developed countries. The overall 5-year survival rate for patients diagnosed with this disease is estimated to be approximately 80%. The standard management of patients with early-stage endometrial cancer is total abdominal hysterectomy and bilateral salpingo-oophorectomy, with or without pelvic and para-aortic lymphadenectomy, depending on risk factors. The evolution of minimally invasive techniques, such as laparoscopy and robotic-assisted surgery, has established such approaches as the current standard of care. Among the proven benefits of the minimally invasive approach are lower rates of blood loss and transfusions, shorter length of stay, and lower rates of postoperative complications. In addition, a minimally invasive approach is equivalent in oncologic outcomes when compared to an open approach. Given these benefits, a laparoscopic or robotic approach should be the recommended surgical approach in the management ...
Acta obstetricia et gynecologica Scandinavica, 1998
Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 10, 1994
Pathogenesis and Management, 2005
Modern Management of Abnormal Uterine Bleeding, 2008
Endoskopisk og onkologisk seksjon Kvinnesenteret Ullevål universitetssykehus 0407 Oslo B A KG R U... more Endoskopisk og onkologisk seksjon Kvinnesenteret Ullevål universitetssykehus 0407 Oslo B A KG R U N N. Målet med studien var å evaluere bruken av laparoskopisk kirurgi i behandlingen av pasienter med tidlig stadium av endometriecancer.
Fertility and Sterility, 2005
surgical intervention. A larger, prospective study is currently underway to determine whether loc... more surgical intervention. A larger, prospective study is currently underway to determine whether location or maximum fibroid diameter affects IUI success.
INTRODUCTION Establishment of sufficient muscle relaxation is essential in laparoscopic surgery. ... more INTRODUCTION Establishment of sufficient muscle relaxation is essential in laparoscopic surgery. During laparoscopy, surgeons can experience abdominal contractions in their patients. Deep neuromuscular block (NMB) has the potential to prevent such episodes. In this study, we explored if deep NMB reduces the incidence of sudden abdominal contractions as compared with standard NMB. METHODS This was a pre-planned secondary analysis of a randomized, controlled study. A total of 110 patients scheduled for laparoscopic hysterectomy were randomized to either deep NMB and 8 mmHg pneumoperitoneum (deep NMB group) or single-bolus NMB and 12 mmHg pneumoperitoneum (standard NMB group). NMB was established with rocuronium and reversed with sugammadex. Two gynaecologists registered episodes of sudden abdominal contractions, alarms from the insufflator due to increased intraabdominal pressure and incidences with tightness of the abdominal wall. RESULTS No sudden abdominal contractions were detecte...
Obstetrical & Gynecological Survey, Aug 1, 1989
This study's aim was to determine whether the inclusion of superficial perineal structures in a f... more This study's aim was to determine whether the inclusion of superficial perineal structures in a finite-element simulation of vaginal delivery impacts the pubovisceral muscle and perineal body, two common sites of birth-related injury. The hypothesis, inferred from prevailing literature, was that these structures would have minimal influence (differences less than +10%). Two models were made using the Visible Human Project's female cadaver to create a rigid, fixed pelvis, musculature held by spring attachments to that pelvis, and a rigid, ellipsoidal fetal head prescribed with an inferior displacement to simulate delivery. Injury site stretch ratios and fetal head and perineal body displacements and angles of progression were compared between the Omitted Model (which excluded the superficial perineal structures as is common practice) and the Included Model (which included them). Included Model stretch ratios were þ107%, 29.84% and 214.6% compared to Omitted Model perineal body and right and left pubovisceral muscles, respectively. Included Model peak perineal body inferior displacement was þ72.5% greater while similar anterior-posterior displacements took longer to reach. These results refute our hypothesis, suggesting superficial perineal structures impact simulations of vaginal delivery by inhibiting perineal body anterior-posterior displacement, which stretches and inferiorly displaces the perineal body.
Journal of Minimally Invasive Gynecology, 2013
Bjog: An International Journal Of Obstetrics And Gynaecology, May 16, 2007
Objective To compare the impact of 1000 micrograms of self-administered vaginal misoprostol versu... more Objective To compare the impact of 1000 micrograms of self-administered vaginal misoprostol versus self-administered vaginal placebo at home on preoperative cervical ripening in both premenopausal and postmenopausal women before operative hysteroscopy. Design Two separate but identical parallel, randomised, double-blind, placebo-controlled sequential trials, one in premenopausal women and one in postmenopausal women. The boundaries for the sequential trials were calculated on the primary outcomes of a difference of cervical dilatation ‡1 mm, with the assumption of a type 1 error of 0.05 and a power of 0.95. Setting Norwegian university teaching hospital. Sample Eighty-six women referred to outpatient operative hysteroscopy. Methods The women were randomised to either 1000 micrograms of self-administered vaginal misoprostol or self-administered vaginal placebo the evening before outpatient operative hysteroscopy.
Ultrasound in Obstetrics and Gynecology, 2008
similar to those on MRI with the ''sausage in a tube'' appearance. On CT, findings were interpret... more similar to those on MRI with the ''sausage in a tube'' appearance. On CT, findings were interpreted as metastatic ovarian cancer in 2 women. Path showed poorly differentiated adenocarcinoma in 9/10, mixed müllerian tumor in 1/10; invasion of adjacent uterus, ovary, cul de sac, mesentery/peritoneum or bowel was present in 6/10 women. Conclusions: Primary tubal carcinoma usually presents at an advanced stage. In our series a prospective diagnosis was not made on CT or US. However, the correct diagnosis was suggested based on MRI in our small sample with similar findings in all cases: a solid enhancing adnexal mass partly or completely located within a dilated fallopian tube.
Acta Obstetricia et Gynecologica Scandinavica, 2001
Journal of Vascular and Interventional Radiology, Oct 1, 2009
To compare long-term symptom recurrence and 6-month magnetic resonance (MR) imaging results after... more To compare long-term symptom recurrence and 6-month magnetic resonance (MR) imaging results after two different treatments for uterine leiomyomas. Sixty-six women with uterine leiomyomas were randomized to undergo uterine artery embolization (UAE) or laparoscopic bilateral occlusion of uterine arteries. Contrast-enhanced MR imaging was performed before treatment and after 6 months. Fifty-eight patients received treatment. Median follow-up time was 48 months (range, 8-73 months). Clinical failure and symptom recurrence occurred in 14 patients after laparoscopy (48%) and in five after UAE (17%; P = .02, log-rank test). Hysterectomy was performed in two patients after UAE (7%) and in eight after laparoscopy (28%; P = .041). Six-month MR imaging results were available for 26 patients treated with UAE and 22 treated with laparoscopy. The mean uterine volume was reduced by 51% (range, 16%-86%) after UAE treatment, compared with 33% (range, 6%-77%) after laparoscopy (P = .001). Complete leiomyoma infarction was seen in all 26 patients in the UAE group and in only five patients in the laparoscopy group (P < .001). Eleven patients experienced symptom recurrence later than 6 months. Uterine volume reduction at 6 months was 24% in this group, compared with 48% in the 37 patients with no recurrence (P = .004). Incomplete infarction of leiomyomas was seen in eight of the 11 cases of recurrence (73%) versus nine of 37 cases without recurrence (24%; P = .009). Recurrence rate was significantly lower after UAE than after laparoscopic treatment. Larger volume reduction and more complete devascularization of leiomyomas were found after UAE treatment and among patients with no recurrence.
Journal of The American Association of Gynecologic Laparoscopists, Aug 1, 2001
Gynaecological Endoscopy, Nov 14, 2003
Objective To evaluate the diagnostic accuracy of Pipelle endometrial biopsies before surgical tre... more Objective To evaluate the diagnostic accuracy of Pipelle endometrial biopsies before surgical treatment of uterine bleeding disorders. Design Retrospective analysis. Setting County Hospital unit specializing in operative hysteroscopy. Interventions Routine outpatient endometrium biopsies were taken from 628 patients because of uterine bleeding disorders. Of these patients, 249 underwent transcervical resection of the endometrium (TCRE) and 75 had a hysterectomy within 6 months. Results Comparing the two subgroups ‘malignant’ and ‘benign’, the positive predictive value for endometrial malignancy was 100% (95% CI, 73.5–100). Insufficient tissue was obtained in five cases (1.5%); in three there were submucous fibroids, in one sampling took place after TCRE, and one patient had atrophic endometrium. Conclusion Adequate preoperative histological assessment of the endometrium is feasible with Pipelle biopsies, and they are highly accurate in detecting endometrial malignancy.
Acta Obstetricia et Gynecologica Scandinavica, Jul 1, 2001
Objective. To evaluate the diagnostic accuracy of transvaginal ultrasonography, sonohysterography... more Objective. To evaluate the diagnostic accuracy of transvaginal ultrasonography, sonohysterography and hysteroscopy in patients presenting with abnormal uterine bleeding. Design. Prospective, blind, comparative study. Setting. Outpatient clinic and day surgery unit of a district hospital specializing in operative hysteroscopy. Patients. One hundred consecutive patients referred with abnormal uterine bleeding (AUB). Interventions. Transvaginal ultrasonography and sonohysterography were performed in the outpatient clinic. Within 1 week, all patients underwent operative hysteroscopy. Main outcome measures. All diagnoses established by transvaginal ultrasonography, and sonohysterography were compared to the appearance of the cavity using hysteroscopy as well as the histological diagnosis from removed tissues. Results. In 88 patients information suitable for analysis was obtained by all methods. The detection rate of focal intrauterine pathology using sonohysterography was (94.1%), but was significantly lower with transvaginal ultrasonography (23.5%). In about 75% of all cases none of the methods used was able to correctly detect endometrial hyperplasia. Conclusions. Sonohysterography was significantly better than transvaginal ultrasonography in detecting focal intrauterine pathology. Visual examination at operative hysteroscopy yielded no additional information to the detection or exclusion of focal lesions than was obtained at outpatient sonohysterography. All methods performed equally in assessing endometrial pathology. We conclude that sonohysterography may replace diagnostic hysteroscopy in many patients with AUB.
Endometrial carcinoma is the most common gynecologic cancer in developed countries. The overall 5... more Endometrial carcinoma is the most common gynecologic cancer in developed countries. The overall 5-year survival rate for patients diagnosed with this disease is estimated to be approximately 80%. The standard management of patients with early-stage endometrial cancer is total abdominal hysterectomy and bilateral salpingo-oophorectomy, with or without pelvic and para-aortic lymphadenectomy, depending on risk factors. The evolution of minimally invasive techniques, such as laparoscopy and robotic-assisted surgery, has established such approaches as the current standard of care. Among the proven benefits of the minimally invasive approach are lower rates of blood loss and transfusions, shorter length of stay, and lower rates of postoperative complications. In addition, a minimally invasive approach is equivalent in oncologic outcomes when compared to an open approach. Given these benefits, a laparoscopic or robotic approach should be the recommended surgical approach in the management ...
Acta obstetricia et gynecologica Scandinavica, 1998
Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 10, 1994
Pathogenesis and Management, 2005
Modern Management of Abnormal Uterine Bleeding, 2008
Endoskopisk og onkologisk seksjon Kvinnesenteret Ullevål universitetssykehus 0407 Oslo B A KG R U... more Endoskopisk og onkologisk seksjon Kvinnesenteret Ullevål universitetssykehus 0407 Oslo B A KG R U N N. Målet med studien var å evaluere bruken av laparoskopisk kirurgi i behandlingen av pasienter med tidlig stadium av endometriecancer.
Fertility and Sterility, 2005
surgical intervention. A larger, prospective study is currently underway to determine whether loc... more surgical intervention. A larger, prospective study is currently underway to determine whether location or maximum fibroid diameter affects IUI success.
INTRODUCTION Establishment of sufficient muscle relaxation is essential in laparoscopic surgery. ... more INTRODUCTION Establishment of sufficient muscle relaxation is essential in laparoscopic surgery. During laparoscopy, surgeons can experience abdominal contractions in their patients. Deep neuromuscular block (NMB) has the potential to prevent such episodes. In this study, we explored if deep NMB reduces the incidence of sudden abdominal contractions as compared with standard NMB. METHODS This was a pre-planned secondary analysis of a randomized, controlled study. A total of 110 patients scheduled for laparoscopic hysterectomy were randomized to either deep NMB and 8 mmHg pneumoperitoneum (deep NMB group) or single-bolus NMB and 12 mmHg pneumoperitoneum (standard NMB group). NMB was established with rocuronium and reversed with sugammadex. Two gynaecologists registered episodes of sudden abdominal contractions, alarms from the insufflator due to increased intraabdominal pressure and incidences with tightness of the abdominal wall. RESULTS No sudden abdominal contractions were detecte...