Transcervical Access Research Articles

Transcervical carotid stenting with flow reversal protection: Experience in high-risk patients

Carotid angioplasty and stenting (CAS) with cerebral embolic protection is a safe alternative to carotid endarterectomy in high-risk patients. Among the various systems proposed for cerebral protection, transcervical CAS avoids crossing the lesion without protection and eliminates the complications associated with transfemoral access. This study analyzes our experience and the results obtained with a transcervical stenting technique for carotid revascularization. From January 2005 to June 2006, 62 CAS were performed in our center in high-risk patients with >70% stenosis (38.7% had a previous neurologic event and 61.3% were asymptomatic). The indications for CAS were severe heart disease (45.1%), severe pulmonary disease (6.4%), paralysis of the contralateral laryngeal nerve (6.4%), recurrent stenosis (3.2%), and high carotid lesion (1.6%). Twenty-one patients were >80 years old. A complete neurologic examination was performed by a stroke neurologist in all patients before and after stenting. The protection system used was carotid flow reversal by transcervical access. Transcranial Doppler monitoring was done during the procedure in 35 patients. We analyzed technical success, the presence of high-intensity transient signals during the procedure, neurologic morbidity and mortality at 30 days and 6 months, and stent patency at 6 months (range, 1 to 18 months). Technical success was 96.8%. Perioperative high-intensity transient signals were observed in two patients (5.7%). In the immediate postoperative period, one patient had a transient ischemic attack of the anterior cerebral artery and another had a stroke, with contralateral hemiplegia. At 48 hours after discharge, a third patient returned to the hospital with a severe cerebral hemorrhage that required surgical drainage; hence, neurologic morbidity was 4.9%. There were no deaths at 6 months. Among the total, 98.4% of the stents remained patent, two showed restenosis of 50% to 70%, and one restenosis of >70%. No patients presented a neurologic event during the follow-up. Transcervical carotid artery stenting with flow reversal cerebral protection is a relatively simple, safe technique that avoids instrumentation of the aortic arch and crossing the target lesion without protection. It is less expensive than techniques requiring a filter device and provides excellent outcome with an acceptable incidence of complications.

Methods of biopsy specimen reception for adenomyosis histologic verification, analysis of efficiency

The comparative experimental analysis of histologic methods of adenomyosis diagnosis is resulted. Advantage of punction miometrial biopsy by transcervical access above transabdominal one, and also insufficient efficiency of resection and pinch miometrial biopsy are established.

Fertility and ovum fertilization rate after laparoscopic or transcervical intrauterine artificial insemination of oxytocin-treated ewes

Based on our previous work, we found that exogenous oxytocin induces uterine tetany and cervical dilation, and permits transcervical access to the uterus. However, the oxytocin does not reduce sustained sperm transport from the uterus to the oviducts. Thus, we hypothesized that exogenous oxytocin may be a useful adjunct to transcervical intrauterine AI procedures for sheep: two experiments were conducted to test our hypothesis. In Experiment 1, purebred ewes (n = 75/group) were artificially inseminated intrauterine with either laparoscopic or oxytocin-transcervical (i.e., 200 USP units of oxytocin 30 min before AI) procedures. At 54 h after progestogenated pessaries were removed, ewes were inseminated with 200 × 10 6 sperm/0.25 ml of fresh, extended semen, which was collected from a purebred ram of the corresponding breed. Pregnancy rate was greater (P < 0.05) after laparoscopic (37.5%) than after transcervical AI (0%). Because of the disappointing results of Experiment 1, Experiment 2 was conducted to determine whether oxytocin or the AI procedure per se reduced ovum fertilization rate. Treatments were designed in a 2 × 2 factorial arrangement. At 60 h after norgestomet implant removal and 10 min before either laparoscopic or transcervical (cervical in a saline group) AI with 100 × 10 6 sperm/0.25 ml, ewes (n = 10/group) received an intravenous injection of either isotonic saline or 200 USP units of oxytocin. Fertilization rate, which was determined 72 h after AI, was greater (P < 0.05) after laparoscopic than after transcervical/cervical AI (92.5 vs 28%), but oxytocin treatment did not affect fertilization rate. The results indicate that exogenous oxytocin did not reduce ovum fertilization rate, but the transcervical AI procedure per se seemed to reduce fertilization rate.

New methods for transcervical cannulation of the Fallopian tube

Technological advances have led to major improvements in the design and application of Fallopian tube cannulation devices using the transcervical approach. Presently such cannulation systems are being used to overcome infertility disorders. These transcervical access systems are now able to displace debris that may block the tube, break down intraluminal adhesions or place egg, sperm or embryos in the tube to facilitate conception. Conversely, these same or modified devices could be used to place sclerosing agents or occlusive devices within the Fallopian tubes using similar transcervical access technology. Transcervical delivery systems incorporating a very fine endoscopic fiber have also been developed to visibly assess the inside lumen of the Fallopian tube using a transcervical approach. Such a system could be used to accurately identify specific sites in the tube for placement of such devices. The potential for placing permanent or temporary devices in the tube and the option of reversible sterilization may become a possibility in the future. One of the biggest obstacles against a wide distribution of these devices, particularly in third world countries, will be cost and the relative technical complexity in using them. These factors will need to be addressed more carefully in assessing the overall strategy of population control. The pressure on governments and international agencies to place more resources into population control may facilitate the accelerated development, application and cost containment of these new devices and delivery systems.

Oestrous synchronization, semen collection and artificial insemination of farmed red deer ( Cervus elaphus) and fallow deer ( Dama dama)

The application of artificial insemination technology within the red deer and fallow deer farming industries is in its infancy. However, its future potential is enormous, particularly in relation to genetic improvement programmes and international exchange of genetic material. This paper reviews the present state of such technology for these two species by discussing the major components of oestrous synchronisation, semen collection/cryopreservation and insemination techniques. Artificial oestrous synchronisation overcomes problems associated with the detection of natural oestrus. Synchronisation can be achieved through the administration of progestagens or strategic administration of prostaglandin analogues. Most studies have investigated the use of the controlled internal drug release (CIDR) device, with 12–14 day insertion plus 200–250 IU pregnant mares' serum gonadotrophin (PMSG) at device withdrawal (red deer) or 14 day insertion alone (fallow deer) being the more common treatment regimens within the natural breeding season. Administration of cloprostenol on Days 13–14 of the oestrous cycle is also highly effective in fallow deer. Future studies need to refine synchronisation regimens to increase oestrous synchrony. Semen collection, which is under seasonal constraints, is mainly by electro-ejaculation, with semen processed for cryopreservation using standard techniques. The development of artificial vagina (AV) collection methods holds promise for safer and more efficient semen collection from deer. Transcervical access to the uterine lumen has proven difficult in red and fallow deer. Presently, most fixed-time inseminations are performed per vaginam (intravaginal or intracervical) or laparoscopically (intrauterine). Conception rates to per vaginam inseminations ((20–80) × 10 6 motile spermatozoa) at approximately 48 h after CIDR device withdrawal have been highly variable and generally low (less than 40%) for both species, with a tendency towards better rates (40–60%) with double inseminations (44 and 68 h) in red deer and higher concentrations of motile spermatozoa (more than 100 × 10 6) for fallow deer. Conception rates to laparoscopic intrauterine inseminations ((10–40) × 10 6 motile spermatozoa) at 54–56 h (red deer) or 65–70 h (fallow deer) after CIDR device withdrawal have been more consistent and generally higher (60–70%) for both species.

Transcervical access and intra-luminal imaging of the Fallopian tube in the non-anaesthetized patient; Preliminary results using a new technique for Fallopian access

A study was performed to evaluate a new transcervical, Fallopian tube access system for use in falloposcopy procedures without the need for conventional hysteroscopy or uterine distension. Visualization was accomplished by the use of a 0.5 mm falloposcope which was delivered to the Fallopian tube by a new linear everting catheter. The linear everting catheter allows access to the Fallopian tube by means of a flexible, tubular rolling membrane which can safely negotiate the tortuous anatomy from the ostium to the ampulla. Concurrent laparoscopy was performed solely for supervision purposes and not for tubal manipulations in 13 Fallopian tube access procedures in 10 patients. The ostia were visualized in 12 cases and the Fallopian tube was accessed in all 12 without complications. As a precursor for future gamete and embryo transfer procedures, intra-tubal insemination was performed by visualizing the ostia, accessing the Fallopian tubes, and obtaining successful isthmic-ampullary, intra-luminal images.