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31.
Autotransplantation presently constitutes the best option for the surgical treatment of non-palpable retained intra-abdominal testes. Silber first proposed this technique in 1978; it is not suitable in children under 3 years of age because of the small caliber of the testicular artery. In 1986 Dòmini, mindful of the problem of arterial vascularisation, carried out refluent testicular autotransplantation (RTAT), where a natural anastomosis between the testicular and deferential arteries is used. Venous drainage is guaranteed by performing a microsurgical anastomosis between the internal spermatic and inferior epigastric veins.At our institution this technique has been employed since 1990, replacing staged orchidopexy. We report a 2-year experience (1990–1992) in seven children who underwent RTAT and discuss the results obtained and the technique used. 相似文献
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S. D. Bell A. M. Peters 《European journal of nuclear medicine and molecular imaging》1991,18(2):87-90
Measurement of individual kidney glomerular filtration rate (IKGFR) from the gamma-camera technetium 99m diethylene triamine penta-acetic acid (99mTc-DTPA) renogram requires a continuous measurement of arterial activity. This is usually based on a region of interest (ROI) placed over the cardiac blood pool on the posterior view, with the assumption of negligible contamination from activity in the extravascular space of the chest wall. By injecting a small dose of technetium 99m human serum albumin (HSA) before the99mTc-DTPA in 12 patients undergoing routine renography, the contribution of extravascular activity to the total signal recorded over the cardiac blood pool was calculated to be 11.0% (SE 2.1%) 1.5 min after DTPA injection, rising to 35.1% (SE 2.5%) at 15 min. Subtraction of the time-activity curve recorded from a ROI of the same size over the right lung generated a pure blood signal as shown by almost identical HSA/DTPA signal ratios recorded in blood samples taken 5 min after HSA and 15 min after DTPA and from the gamma-camera at the corresponding times. The effect of using a cardiac blood pool time-activity curve uncorrected for extravascular activity was to overestimate IKGFR by an average factor of 1.17 (SE 0.03).
Offprint requests to: A.M. Peters 相似文献
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Mariko Sakata Masaji Utsu Kazuo Maeda 《The Ultrasound Review of Obstetrics & Gynecology》2006,6(3):135-140
Objectives. Twin to twin transfusion syndrome (TTTS) is one of the most important problems for perinatal management of monochorionic twins. Since TTTS is deeply related to the prognoses of both fetuses, fetal circulation and placental blood flow of monochorionic twins were studied with the purpose of clarifying characteristic features.
Methods. The patterns and numbers of vascular anastomoses were checked on the placental surface, arterio-arterial (A-A) anastomosed vessels by ultrasound, and circulatory changes were studied with relation to uterine contraction.
Results. The high risk of monochorionic twin pregnancies was largely related to the patterns of vascular anatomy of the placenta and numbers of anastomosed vessels. The first placental vascular connection detected in vivo was the A-A anastomosis characterized by the bidirectional flow waveform in pulsed Doppler velocimetry.
Conclusion. TTTS is related to anastomosed vessels on the surface of placenta. To manage and prevent TTTS, fetal circulation and placental blood flow should be carefully observed. 相似文献
Methods. The patterns and numbers of vascular anastomoses were checked on the placental surface, arterio-arterial (A-A) anastomosed vessels by ultrasound, and circulatory changes were studied with relation to uterine contraction.
Results. The high risk of monochorionic twin pregnancies was largely related to the patterns of vascular anatomy of the placenta and numbers of anastomosed vessels. The first placental vascular connection detected in vivo was the A-A anastomosis characterized by the bidirectional flow waveform in pulsed Doppler velocimetry.
Conclusion. TTTS is related to anastomosed vessels on the surface of placenta. To manage and prevent TTTS, fetal circulation and placental blood flow should be carefully observed. 相似文献
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《Neuro-Chirurgie》2021,67(5):487-490
IntroductionWhen the culprit vessel in hemifacial spasm (HFS) is hard to determine, this is a challenge in microvascular decompression (MVD) surgery. In such a situation, small arteries such as perforators to the brainstem might be suspected. But small arteries are omnipresent near the facial nerve root exit/entry zone (fREZ). How to decide whether a given small artery is responsible for HFS is unclear.MethodWe report a case with a previously unreported form of neurovascular impingement, in which the culprit was found to be the recurrent perforating artery (RPA) from the anterior inferior cerebellar artery (AICA). An aberrant anatomic configuration of the RPA was found intraoperatively, which we thought was responsible for generating focal pressure on the facial nerve.Case reportA 62-year-old woman presented with a 1-year history of paroxysmal but increasingly frequent twitching in her right face. MRI showed tortuosity of the vertebral artery and apparently marked neurovascular impingement on the asymptomatic left side, while only the right AICA could be implicated as the possible culprit. Hemifacial spasm was diagnosed based on the typical clinical manifestation, and MVD was performed. The pre-meatal segment of the AICA was found not to be impinging the facial nerve at any susceptible portion near the fREZ: root exit point, attached segment, or root detachment point. The real culprit was in fact the RPA. This occult culprit vessel was tortuous, forming a coil-shaped twist which was interposed between the facial nerve and the intermediate nerve near the root detachment point. Focal pressure atrophy of the nerve was clearly observed at the compressing site. The patient achieved total spasm relief immediately after surgery, and remained spasm-free at 1-year follow-up, without any postoperative complications.ConclusionMVD is the only curative treatment for hemifacial spasm, but with a failure rate of around 10%. Mistaking the real culprit has been reported to be the most likely reason for surgical failure. Therefore, intraoperative identification of atypical occult forms of vascular compression is of importance to improve surgical outcome. In the present case, the RPA formed a coil-shaped twist, which inflicted focal vascular compression causing hemifacial spasm. We recommend careful inspection of the recurrent perforating artery during MVD for HFS, and decompressing any such neurovascular impingement. 相似文献
38.
James C. Melville Christopher Scott Manis Jonathan W. Shum Dhafer Alsuwied 《Journal of oral and maxillofacial surgery》2019,77(4):874.e1-874.e13
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