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At least 1,261 records · Page 70Linked to original sources

PubMed2006

A new technique for pterygium excision: air-assisted dissection.

PURPOSE: To introduce a new technique which aids to remove the pterygium head and facilitates the establishment of a smooth and clear corneal surface without extra scraping or polishing. MATERIAL AND METHODS: We used 12 eyes of 12 patients undergoing pterygium excision. Air was injected into the side of the cap of the pterygium head with a 30-gauge needle, to create a dissection plane between the pterygium head and the cornea. After blunt dissection and excision of the pterygium, the conjunctival autograft technique was applied. Complications, postoperative smoothness and clarity of the cornea, and the recurrence rates were evaluated. RESULTS: Dissection with air was successfully performed in 9 eyes (75%) in which blunt dissection was carried out easily. The corneas were clear and smooth postoperatively. In 3 eyes (25%) dissection with air was not completely successful, and scraping with a crescent blade had to be performed. One of the eyes with incomplete air dissection could not be clearly scraped. No major complications were observed. The recurrence rate was 8.3% (1 eye). CONCLUSION: This new technique is a safe, easy and cheap method for removing the pterygium head from the corneal surface, which also facilitates the establishment of a clear and smooth corneal surface.

Adult↗

PubMed1991

Results of a nationwide study on the three-field lymph node dissection of esophageal cancer.

In order to determine the operative indications of three-field lymph node dissection of esophageal cancer, attempts were made to collect data concerning procedures performed between 1983 and 1989 in major institutions in Japan, and the results from institutions performing three-field or two-field lymph node dissection were compared. The treatment results of three-field lymph node dissection were better than those after two-field dissection, except for early or advanced cancer. The survival rate improved by the three-field as compared with the two-field lymph node dissection; however, since surgery was invasive, some complications such as recurrent nerve paralysis were frequent. The results show that the indication of three-field lymph node dissection has to be carefully determined for each patient.

Abdomen↗

PubMed2004

Planned neck dissection following chemo-radiotherapy in advanced HNSCC.

BACKGROUND: Neck dissection has traditionally played an important role in the management of patients with regionally advanced head and neck squamous cell carcinoma (HNSCC) treated with radical radiotherapy alone. However, with the incorporation of chemotherapy in the therapeutic strategy for advanced HNSCC and resultant improvement in outcome the routine use of post chemo-radiotherapy neck dissection is being questioned. METHODS: Published data for this review was identified by systematically searching MEDLINE, CANCERLIT & EMBASE databases from 1995 until date with restriction to the English language. RESULTS: There is lack of high quality evidence on the role of planned neck dissection in advanced HNSCC treated with chemo-radiotherapy. A systematic literature search could identify only one small randomized controlled trial (Level I evidence) addressing this issue, albeit with major limitations. Upfront neck dissection followed by chemo-radiotherapy resulted in better disease-specific survival as compared to chemoradiation only. Several single arm prospective and retrospective reports were also identified with significant heterogeneity and often-contradictory conclusions. CONCLUSIONS: Planned neck dissection after radical chemo-radiotherapy achieves a high level of regional control, but its ultimate benefit is limited to a small subset of patients only. Unless there are better non-invasive ways to identify residual viable disease, the role of such neck dissection shall remain debatable. A large randomized controlled trial addressing this issue is needed to clarify its role and provide evidence-based answers.

Journal Article↗

PubMed2005

Dissection of a DNA-damage-induced transcriptional network using a combination of microarrays, RNA interference and computational promoter analysis.

BACKGROUND: Gene-expression microarrays and RNA interferences (RNAi) are among the most prominent techniques in functional genomics. The combination of the two holds promise for systematic, large-scale dissection of transcriptional networks. Recent studies, however, raise the concern that nonspecific responses to small interfering RNAs (siRNAs) might obscure the consequences of silencing the gene of interest, throwing into question the ability of this experimental strategy to achieve precise network dissections. RESULTS: We used microarrays and RNAi to dissect a transcriptional network induced by DNA damage in a human cellular system. We recorded expression profiles with and without exposure of the cells to a radiomimetic drug that induces DNA double-strand breaks (DSBs). Profiles were measured in control cells and in cells knocked-down for the Rel-A subunit of NFkappaB and for p53, two pivotal stress-induced transcription factors, and for the protein kinase ATM, the major transducer of the cellular responses to DSBs. We observed that NFkappaB and p53 mediated most of the damage-induced gene activation; that they controlled the activation of largely disjoint sets of genes; and that ATM was required for the activation of both pathways. Applying computational promoter analysis, we demonstrated that the dissection of the network into ATM/NFkappaB and ATM/p53-mediated arms was highly accurate. CONCLUSIONS: Our results demonstrate that the combined experimental strategy of expression arrays and RNAi is indeed a powerful method for the dissection of complex transcriptional networks, and that computational promoter analysis can provide a strong complementary means for assessing the accuracy of this dissection.

Ataxia Telangiectasia Mutated Proteins↗

PubMed1997

Reappraisal of the role of axillary lymph node dissection in the conservative treatment of breast cancer.

PURPOSE: The purpose of this study was (1) to review systemic therapy practice patterns to assess how information regarding nodal status currently influences systemic therapy decisions, and (2) to review long-term outcome of patients who do not undergo axillary dissection compared with patients who do. METHODS AND MATERIALS: For the current practice patterns portion of the study, the records of 292 patients who presented in the past 3 years with invasive breast cancer and underwent conservative surgery were reviewed to determine systemic therapy administered with respect to patient age, primary tumor size, clinical nodal status, and presenting symptoms. For the long-term outcome portion of the study, the records of 955 patients with invasive breast cancer who underwent conservative surgery and radiation therapy before December 1989 were reviewed. Patient characteristics and outcome of those patients who underwent axillary dissection (n = 565, 59%) were compared with a cohort of patients treated during the same era who did not undergo axillary dissection (n = 390, 41%). RESULTS: For the current practice-patterns cohort, information regarding nodal status appeared to influence adjuvant systemic therapy for those patients less than 50 years of age and for those patients with palpable masses who were older than 50. Patients older than 50 with nonpalpable mammographically detected tumors have a low probability of nodal involvement and information regarding nodal status rarely changed therapy in this group of patients. In the long-term outcome study, there were no significant differences in the rates of distant metastasis, disease-free survival, or overall survival between those patients who underwent lymph node dissection and those who did not. CONCLUSION: For selected patients, axillary lymph node dissection appears to have little influence on subsequent management and long-term outcome. These data suggest that it is time to reassess the role of axillary lymph node dissection in patients who undergo conservative surgery and radiation therapy.

Actuarial Analysis↗

PubMed2006

Video-assisted thoracoscopic dissection of the brachial plexus: cadaveric study and illustrative case.

OBJECTIVE: Standard surgical approaches to the brachial plexus require an open operative technique with extensive soft tissue dissection. A transthoracic endoscopic approach using video-assisted thoracoscopic surgery (VATS) was studied as an alternative direct operative corridor to the proximal inferior brachial plexus. METHODS: VATS was used in cadaveric dissections to study the anatomic details of the brachial plexus at the thoracic apex. After placement of standard thoracoscopic ports, the thoracic apex was systematically dissected. The limitations of the VATS approach were defined before and after removal of the first rib. The technique was applied in a 22-year-old man with neurofibromatosis who presented with a large neurofibroma of the left T1 nerve root. RESULTS: The cadaveric study demonstrated that VATS allowed for a direct cephalad approach to the inferior brachial plexus. The C8 and T1 nerve roots as well as the lower trunk of the brachial plexus were safely identified and dissected. Removal of the first rib provided exposure of the entire lower trunk and proximal divisions. After the fundamental steps to the dissection were identified, the patient underwent a successful gross total resection of a left T1 neurofibroma with VATS. CONCLUSION: VATS provided an alternative surgical corridor to the proximal inferior brachial plexus and obviated the need for the extensive soft tissue dissection associated with the anterior supraclavicular and posterior subscapular approaches.

Adult↗

PubMed2006

Learning curve for total gastrectomy with D2 lymph node dissection: cumulative sum analysis for qualified surgery.

BACKGROUND: This study was conducted to evaluate the leaning curve of D2 lymph node dissection for patients with gastric cancer in a high-volume center. METHODS: The authors prospectively reviewed the data of all patients who underwent total gastrectomy with D2 lymph node dissection during a 4-year period. Retrieved lymph node number was used as a surrogate marker of oncological outcome. The retrieved lymph node number cut-off value required for satisfactory D2 lymph node dissection was defined as >25. Cumulative sum analysis was used to examine the learning curves of individual surgeons at target accuracy rates of 85%, 90%, 92.5%, 95%, and 98%. RESULTS: Two junior staff surgeons performed 198 curative-intent total gastrectomies with D2 lymph node dissections during the study period; their success rates exceeded 90%. Operating time decreased with operative experience (Pearson correlation coefficient = -0.515, P < 0.001). The learning period for total gastrectomy with D2 lymph node dissection for these two junior members of staff was calculated as 23-35 cases, presuming a 92.5% success rate. CONCLUSIONS: The current study suggests that the surgical learning period for D2 lymph node dissection extends to at least 23 cases or 8 months. In clinical trials containing gastric cancer surgery, the learning curve for qualified surgery from the standpoint of oncological outcome should be considered to minimize bias due to surgeon-associated factors.

Adenocarcinoma↗

PubMed2005

Retroperitoneal lymph node dissection in the treatment of low-stage nonseminomatous germ cell tumors of the testicle.

Nonseminomatous germ cell tumors of the testicle are highly treatable and curable. The evolution of cancer control for this disease has demonstrated an effective integration of medical and surgical approaches over the last 30 years. Current emphasis in the therapy of nonseminomatous germ cell tumors focuses on minimizing treatment-related morbidity while maintaining consistently high cure rates. Retroperitoneal lymph node dissection in experienced hands is a critical component of the treatment armamentarium in this disease. Retroperitoneal lymph node dissection is an accurate staging tool that provides important information in determining the need for chemotherapy. When performed properly, retroperitoneal lymph node dissection eliminates the retroperitoneum as a site for relapse, which in turn provides emotional and psychological relief to the patient and simplifies the follow-up protocol. Retroperitoneal lymph node dissection alone can also provide high cure rates in patients with clinical low-stage disease and high-risk factors such as lymphovascular invasion or predominance of embryonal histology in the primary tumor. Teratoma is known to be chemoresistant and, when present in the primary tumor of low-stage patients, may be best treated with primary retroperitoneal lymph node dissection. Primary chemotherapy in the treatment of low-stage nonseminomatous germ cell tumors deserves continual investigation as long-term toxicities become more apparent. Observation is an option for the highly motivated patient, but requires a rigorous follow-up schedule to avoid relapse. Laparoscopic retroperitoneal lymph node dissection is a viable staging tool, however, oncologic control of the retroperitoneum has not been reliably determined.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2005

Lower axillary dissection in breast cancer surgery may be candidate for cases with early breast cancer.

Lower axillary lymph node dissection (lower parts of both the level I and II elements below the second intracostobrachial nerve) and level I and II lymph node dissection were performed on breast cancer patients (n = 54), and the results with the two methods were compared in terms of the status of detected lymph node metastases. For Stage I, N0 cases, the results for pathological classification lymph node metastases (pN) were in agreement between the two dissection methods. And, the occurrence of operated arm swelling wasn't recognized when a side effect was examined with the case (n = 28) that only lower axillary dissection was carried out in case of an operation for breast cancer. Accordingly, it was surmised that lower axillary dissection provides accurate pN information for Stage I, N0 cases. These results indicate that lower axillary dissection has the potential to become an effective, standard surgical procedure for breast cancer patients whose preoperative disease stage is Stage I.

Adult↗

PubMed1975

Dissecting aneurysm of thoracic aorta: reappraisal of radiologic diagnosis.

In a series of 24 cases of acute dissecting aneurysm of the aorta (not including Marfan's disease) the diagnosis was usually suspected on the basis of the clinical picture and plain chest roentgenograms. The most consistent clinical sign was severe pain. Absent pulses and a neurological deficit were each noted in only five patients. In many cases there was no correlation between the clinical picture and the type or the extent of the dissection. Widening of the aortic arch and obliteration of the aortic knob with displacement of the trachea to the right are the most common signs in plain chest roentgenograms. A barium swallow examination in these cases reveals an elongated compression and displacement of the esophagus by the aortic arch. Calcification in the area of the aortic arch is the exception rather than the rule in dissecting aneurysms. Angiography is essential for the definitive diagnosis of dissecting aneurysms. The diagnosis is based on the demonstration of two channels, either by the presence of a linear radiolucency separating the two lumens, or by differences in flow that present as delayed opacification or delayed washout. If only the true lumen is opacified, widening of the outer extraluminal border of the aorta or narrowing of the lumen indicates the presence of a dissection. Abnormal catheter recoil and position were helpful in only two cases, and are not informative when the false lumen is catheterized. Failure to visualize main aortic branches was not always due to involvement by the dissection. It can also be caused by reduced flow due to severe proximal compression of the main lumen. The exact location of the intimal tears is usually not demonstrated unless additional injections are made in the area assumed to contain the tear. If only the false lumen is opacified in the ascending aorta, this can be recognized by the demonstration of a blind end, by failure to visualize the sinuses of Valsalva, from flattening of the medial border of the opacified channel, and from delayed washout in the blind end.

Aged↗

PubMed1996

CT findings after laparoscopic pelvic lymph node dissection and transperineal radioactive seed implantation for prostatic carcinoma.

OBJECTIVE: The purpose of this paper is to describe the CT findings in patients undergoing transperineal sonographically guided radioactive seed implantation with and without laparoscopic lymph node dissection for treatment of carcinoma of the prostate gland. MATERIALS AND METHODS: Ninety-six CT scans of the pelvis were retrospectively reviewed in patients who had undergone radioactive seed implantation of the prostate gland. The CT readings were correlated with the type of procedure each patient had and the pathologic results of laparoscopic lymph node dissection. RESULTS: Of 73 patients who underwent laparoscopic lymph node dissection, 42 were found at CT to have low-attenuation masses along lymph node chains. These masses resembled necrotic nodes. Only one patient who did not undergo laparoscopic lymph node dissection had similar findings. Fourteen patients had fluid collections within the pelvis, 13 of whom had undergone laparoscopic lymph node dissection. Other imaging findings included ectopic seeds (10 patients) and subcutaneous and intrapelvic air (11 patients). All except two patients had negative pathology reports for the removed lymph nodes. CONCLUSION: A wide variety of imaging findings may be seen after radioactive seed implantation and laparoscopic lymph node dissection, including masses that resemble necrotic lymph nodes. Radiologists should be aware of these findings in asymptomatic patients.

Brachytherapy↗

PubMed1992

The effect of live weight gain and live weight loss on body composition of merino wethers: chemical composition of the dissected components.

Chemical composition of the dissected side parts and dissected side was measured during live weight gain (LWG) and live weight loss (LWL) to determine effects on the chemical composition of the dissected side parts. Thirty-five Merino wethers had ad libitum access to the experimental diet (17.23% CP and 12.09 MJ/kg of DE) to grow from 23.0 to 33.0 kg live weight and then were fed to lose a total of 10 kg in three periods of 25 d each at the rate of 133 g/d. Groups of five animals were slaughtered at live weights of 23.0, 26.3, 29.6, and 33.0 kg during LWG and 29.6 kg (first period), 26.3 kg (second period), and 23.0 kg (third period) during LWL. The greater dissected side weight in LWL animals than in LWG animals at 23.0 kg of live weight was due to the significantly greater chemical fat (P < .05) in the LWL animals than in the LWG animals at 23.0 kg. There were no significant differences between treatments in the protein and water weights in the dissected side. The general increase in the chemical fat in the dissected side of the LWL animals was due to the significant increase in the chemical fat in the muscle (P < .01) and bone (P < .01, 23.0 and 26.3 kg and P < .05, 29.6 kg) at each common slaughter weight and subcutaneous fat (P < .05), intermuscular fat (P < .05) kidney and channel fat (P < .05), and total side fat (P < .01) at 23.0 kg.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗

PubMed1987

Sexual function after bilateral retroperitoneal lymph node dissection for nonseminomatous testicular cancer.

This study concerns the sexual functions of 101 patients who had undergone bilateral retroperitoneal lymph node dissection for stage I or II nonseminomatous testicular cancer between 1969 and 1982. All patients were without evidence of disease after at least 4 years of follow-up. Antegrade ejaculation was present in 12 patients, while 89 patients experienced "dry ejaculation." Urine collected after intercourse or masturbation from 75 patients with dry ejaculation showed retrograde ejaculation in 55 and lack of ejaculatory emission into the urethra in 20 patients. Regarding other sexual functions, 17 patients had a diminished sexual desire (especially those patients who had received radiotherapy), 12 experienced difficulty reaching organism, and 6 complained of erectile dysfunction. The incidence of a contralateral hydrocele developing after retroperitoneal lymph node dissection seems to correlate with ligation of the contralateral spermatic vessels and their lymphatics. A review of the literature is presented comparing the types of dissection with the incidence of sexual disorders after retroperitoneal lymph node dissection. Since preserving normal ejaculation and fertility is important, a modified or unilateral retroperitoneal lymph node dissection, when required, is advocated. In patients, with stage I disease the therapy may be limited to an orchiectomy without lymph node dissection. In patients with retroperitoneal lymph node metastases combination chemotherapy with cisplatin and tumor excision gives good results. Patients with true retrograde ejaculation can be treated with alpha-sympathomimetic drugs such as imipramine HCl, and thus be offered the chance of fatherhood by coitus.

Adult↗

PubMed2000

Retroperitoneal lymph node dissection for the management of clinical stage I nonseminoma.

PURPOSE: We review the rationale for the use of retroperitoneal lymph node dissection for clinical stage I nonseminomatous testis cancer. MATERIALS AND METHODS: The published literature regarding the alternative treatments for clinical stage I nonseminoma was reviewed as well as the personal experience of the authors to define the role of retroperitoneal lymph node dissection. RESULTS: Retroperitoneal lymph node dissection alone is curative in 50% to 75% of patients with pathological stage II disease. The only significant long-term morbidity is a 1% chance of small bowel obstruction. If recurrence develops after retroperitoneal lymph node dissection, it is virtually always curable with cisplatin based chemotherapy. CONCLUSIONS: Retroperitoneal lymph node dissection retains a therapeutic and staging capability in these patients. The probability for cure, short and long-term morbidity, and minimal need for long-term followup in these patients indicates that retroperitoneal lymph node dissection continues to be standard therapy for clinical stage I nonseminoma.

Germinoma↗

PubMed2000

Percutaneous transluminal coronary revascularization in women: higher risk of dissection and need for stenting.

BACKGROUND: Even though success rates of percutaneous transluminal coronary angioplasty (PTCA) are influenced by gender, women are at higher risk for adverse procedural events. Plaque dissection has been demonstrated to cause more adverse cardiac events during PTCA in the female gender than the male, but it is not clear how much it could influence stent implantation and procedural complications in the stent era. This study sought to evaluate whether the prevalence of dissection is equal in men and women with similar vessel size, which factors are associated with the risk of this complication and whether stenting has modified the immediate outcome. METHODS: Three hundred thirty-nine lesions were studied in 100 consecutive women and 128 men with a vessel diameter < or = 3.5 mm, who underwent PTCA in our catheterization laboratory between March 1998 and March 1999. RESULTS: Procedural success rates were similar in the two groups (93.9% women vs 97.6% men). Complications were one coronary artery bypass graft and five acute myocardial infarctions. In the group of women, however, there was a significant increase in the incidence of plaque dissection during the procedure (37.9 vs 21.7%, p = 0.001), with consequent increased need for stenting (70.4 vs 52.2%, p < 0.05) to achieve adequate final results. Moreover, dissection was strongly associated (p = 0.03) with procedural complications. Multivariate analysis of the whole patient cohort showed the risk of dissection to be associated only with the female gender (p = 0.009), diabetes (p = 0.029), and type C lesion morphology (p = 0.019). CONCLUSIONS: Women are at higher risk of plaque dissection, which is associated with adverse procedural events and an increased need for stenting.

Aged↗

PubMed2001

[Optimal lymph node dissection for colorectal cancer].

Previous studies on the distribution of positive lymph nodes have revealed that the colon should be resected 10 cm from the tumor on both sides and that the intermediate nodes along the main vessel should be dissected in patients with colon cancer. In rectal cancer, superior lymphatic spread along the inferior mesenteric artery (IMA) is the main metastatic route. The IMA should be dissected immediately after the bifurcation of the left colic artery, and the intermediate lymph nodes should be removed. The positive rate of the lateral lymph nodes is about 10%. The rate of local failure is high and the prognosis is poor in patients with positive lateral lymph nodes, even if the lateral lymph nodes have been dissected. However, it has been reported that lateral lymph node dissection combined with excision of the internal iliac vessels results in good disease-free survival in patients with positive lateral nodes. Therefore the indications for lateral node dissection remain controversial. Lymphatic spread into the mesorectum on the anal side has been shown to be an important factor in local failure. The mesorectum should be resected for up to 4 or 5 cm from the inferior tumor margin in middle rectal cancer, and the entire mesorectum should be removed in lower rectal cancer. Nerve tissue preserved in pelvic autonomic nerve-preserving surgery contains a small amount of lymphoid tissue and lymph nodes. Therefore the extent of lymph node dissection and the area of autonomic nerves to be preserved based on tumor site or tumor penetration remain controversial.

Colonic Neoplasms↗

PubMed2001

Impact of separate versus en bloc pelvic lymph node dissection on the number of lymph nodes retrieved in cystectomy specimens.

PURPOSE: Pelvic lymphadenectomy during radical cystectomy yields a various number of lymph nodes depending on the extent of lymph node dissection and pathologist aggressiveness when searching the specimen. How the surgeon submits lymph nodes for pathological evaluation may also affect how many are retrieved. MATERIALS AND METHODS: Bilateral pelvic lymph node dissection and radical cystectomy for transitional cell carcinoma of the bladder was performed in 32 patients. The extent of lymph node dissection involved standard and extended lymphadenectomy in 20 and 12 cases, respectively. In patients who underwent standard dissection unilateral en bloc submission of the lymph nodes was done with the contralateral lymph node dissection sent as an individual discrete packet. In those who underwent extended dissection all lymph nodes from each side were submitted en bloc or as 6 packets. RESULTS: Standard lymphadenectomy en bloc specimens yielded a mean of 2.4 lymph nodes compared with 8.5 retrieved from individual lymph node specimens (p = 0.003). Extended lymphadenectomy en bloc specimens yielded a mean of 22.6 lymph nodes compared with 36.5 retrieved from the individually submitted packets (p = 0.02). CONCLUSIONS: Submitting pelvic lymph nodes as separate specimens optimizes pathological evaluation of the number of lymph nodes that may be involved with metastatic cancer. Such information is important for identifying patients who may benefit from adjuvant chemotherapy.

Cystectomy↗

PubMed2001

Selective neck dissection in treatment of node-positive neck cases.

Surgical management of patients with cervical metastases of laryngeal and hypolaryngeal cancer has remained a challenge ever since Dr. Crile described the radical neck dissection. The evolution of neck dissection technique confirms this statement. The modification of the radical neck dissection is justified by the severe cosmetic and functional losses related to it and by the fact that despite the comprehensiveness, the recurrences in the neck are still a significant problem. Applying selective neck dissection in node positive cases seems to be justifiable. Expanding the indications for this operation is justified, because in the absence of factors that have destructive effect on fascial compartments of the neck or disrupt the lymphatic flow, such as gross adenopathy or significant extracapsular spread, the principles on which the selective neck dissection is based are still valid. In this paper we report our experience with 10 patients with N1 and N2 who underwent supraomohyoid and lateral neck dissections with follow-up of at least 2 years.

Adult↗