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51.
Minimally invasive video-assisted thyroidectomy: multiinstitutional experience   总被引:29,自引:3,他引:29  
Minimally invasive video-assisted thyroidectomy (MIVAT) was described in 1998. In this study we collected the experience of four third-level referral centers that adopted this technique. A total of 336 patients (279 females, 57 males) were selected for MIVAT. Selection criteria were thyroid volume <15 ml, nodules not exceeding 3.5 cm of diameter, and an absence of thyroiditis, previous neck surgery, or previous irradiation. The procedure, totally gasless, is carried out through a 15 mm central incision above the sternal notch. Dissection is performed under endoscopic vision using conventional and endoscopic instruments. The mean operating time was 69.4 ± 30.6 minutes for lobectomy (range 20–150 minutes) and 87.4 ± 43.5 minutes for total thyroidectomy (range 30–220 minutes). The mean postoperative stay was 1.9 ± 0.8 days. Postoperative complications were 7 transient and 1 definitive recurrent nerve palsies and 11 cases of hypoparathyroidism (9 transient, 2 definitive). Conversion to open surgery was necessary in 15 patients (4.5%). This study confirms in a large number of cases the safety and feasibility of MIVAT, even in different surgical settings where similar results were achieved. The complication rate was not different from that of standard thyroidectomy. Although the operating time appears longer than with conventional procedures, the learning curve demonstrates a sharp decrease with increasing experience and the introduction of new technologies. The number of patients eligible for this approach remains low, thereby limiting its use, but it should be considered a valid option in selected surgical centers, offering some advantages to patients in terms of cosmetic results and postoperative distress.  相似文献   
52.
BACKGROUND: Minimally invasive video-assisted thyroidectomy (MIVAT) has been practiced in our department since 1998. It has some advantages over conventional surgery in terms of postoperative pain and cosmetic result. The aim of this study was to evaluate the use of the Harmonic scalpel (HS) on the performance of this procedure. METHODS: Between October 1998 and January 2001, 116 patients underwent MIVAT. The HS was used for the last 26 operations. We compared this group of patients (HS-G) with a control group (C-G) of 26 patients who had undergone MIVAT before the introduction of the HS. The following parameters were considered: age, gender, preoperative diagnosis, size of the lesion, type of operation (lobectomy or total thyroidectomy), operative time, complication rate, and postoperative hospital stay. RESULTS: The two groups were well matched for age, gender, preoperative diagnosis, lesion size, and type of operation. The mean operative time was significantly reduced in the HS-G for both lobectomy (37.3 +/- 8.4 vs 49.4 +/- 18.0 min) and total thyroidectomy (53.8 +/- 16.3 vs 90.6 +/- 22.1 min). No differences were found for postoperative stay. One patient in the C-G experienced a transient recurrent nerve palsy. There were no other complications. CONCLUSIONS: This study showed that the utilization of the HS for MIVAT is safe and associated with a shorter operative time. A reduction of the rates for such complications such as hypoparathyroidism and recurrent nerve injuries was not possible to demonstrate in the present study. Much larger series are needed for further evaluation of this instrument.  相似文献   
53.
We describe five primary tumors of the adenohypophysis featuring mitochondrion-rich spindle cells. The patient ages ranged from 53 to 71 years (mean 61.6 years); two were female. All presented with panhypopituitarism. Two also had visual field defect. On neuroimaging all tumors showed suprasellar extension and were indistinguishable from pituitary adenoma. None showed imaging or operative evidence of dural involvement. All were gross totally removed: four by transsphenoidal surgery and one by frontal craniotomy. Follow-up ranged from 2 to 68 months (mean 35.4 months). No recurrences were noted. The clinical workup was noncontributory in all but two patients: one (case no. 4) with an oncocytic thyroid adenoma and another (case no. 5) with squamous carcinoma of both the uterine cervix and of vocal cord. Histologically, the five tumors were composed mainly of fascicles of spindle cells with eosinophilic, granular cytoplasm. Mitoses were rare and necrosis was absent. Neoplastic cells were immunoreactive for vimentin, epithelial membrane antigen, S-100 protein, and galectin-3. Stains for pituitary hormones, synaptophysin, chromogranin, glial fibrillary acidic protein, cytokeratin CAM5.2, smooth muscle actin, CD34, and CD68 were negative. No thyroglobulin immunoreactivity was noted in the tumor of case no. 4. Ultrastructurally, the neoplastic cells contained numerous mitochondria with lamellar cristae. The neoplastic cells were linked by intermediate junctions and desmosomes. No secretory granules were noted. The histologic, immunohistochemical, and fine structural features of these tumors were unlike those of pituitary adenoma or any other primary sellar tumor. A derivation from adenohypophyseal folliculostellate cells is suggested.  相似文献   
54.
The incidence of invasive fungal infection is increasing especially in the field of transplantation, affecting as many as 50% of bone marrow transplant (BMT) patients with neutropenia and 5-20% of solid-organ transplant (SOT) recipients. Fusarium species are soil saprophytes and plant pathogens. They may cause superficial mycoses or important opportunistic infections in patients with bone marrow suppression and neutropenia, they have been rarely described in solid organ recipients, and up to now there have been no reports of such infection in isolated liver transplanted patients. We describe a case of disseminated Fusarium solani infection with hepatic localization in a liver transplanted patient that resolved with the administration of amphotericin B. Our observation confirms that Fusarium spp. are emerging pathogens that may most frequently affect not only BMT patients and patients with hematological malignancies, but also SOT patients. They may cause both localized and disseminated infection. In conclusion, Fusarium spp. etiology should be considered in the context of infectious diseases following liver transplantation.  相似文献   
55.
Aim: To study the immune-modulating and anti-oxidant effects of beta-glucan, papaya, lactoferrin, and vitamins C and E on sperm characteristics of patients with asthenoteratozoospermia associated with leucocytosis. Methods: Fifty-one patients referred to our Sterility Center for semen analysis were selected. Sperm parameters were assessed before and after patient's treatment with beta-glucan, lactoferrin, papaya, and vitamins C and E. DNA damage was assessed by the acridine orange test and sperm structural characteristics were evaluated by transmission electron microscopy. Results: After 90 days of treatment, an increase in the percentage of morphologically normal sperm (17.0 ± 5.2 vs. 29.8 ± 6.5) and total progressive motility (19.0± 7.8 vs. 34.8 ± 6.8) were detected. Structural sperm characteristics as well as chromatin integrity were also improved after treatment. In terms of leukocyte concentration in seminal fluid, a significant reduction was recorded (2.2 ± 0.9 vs. 0.9± 0.2). Conclusion: The treatment of an inflammatory process by the synergic action of immune modulators and anti-oxidants could protect sperm during maturation and migration, leading to improved sperm function. (Asian JAndrol 2008 Mar;. 10: 201-206)  相似文献   
56.
Minimally invasive video-assisted thyroidectomy   总被引:40,自引:0,他引:40  
BACKGROUND: In this paper we describe the results of our personal technique for minimally invasive video-assisted thyroidectomy (MIVAT). METHODS: Sixty-seven patients were selected for MIVAT. Selection criteria were nodule size less than 30 mm, thyroid volume less than 20 mL, no thyroiditis, no previous neck surgery or irradiation. The procedure, totally gasless, is carried out through a 15-mm central incision above the sternal notch. Dissection is performed under endoscopic vision, using conventional and endoscopic instruments. RESULTS: We performed 51 lobectomies and 15 total thyroidectomies. Mean operative time was 73.6 minutes for lobectomy and 109.6 minutes for total thyroidectomy. Conversion to open procedure was required twice (3%). We observed 2 cases of transient postoperative hypocalcemia and 1 case of transient recurrent laryngeal nerve palsy. The cosmetic result was considered excellent by most patients. CONCLUSIONS: MIVAT is safe and feasible. The indications are limited at present, but the results are encouraging, and we are optimistic about the future expansion of its applicability.  相似文献   
57.
Solid organ transplantation is the standard treatment to improve both the quality of life and survival in patients with various end-stage organ diseases. The primary barrier against successful transplantation is recipient alloimmunity and the need to be maintained on immunosuppressive therapies with associated side effects. Despite such treatments in renal transplantation, after death with a functioning graft, chronic allograft dysfunction (CAD) is the most common cause of late allograft loss. Recipient recognition of donor histocompatibility antigens, via direct, indirect, and semidirect pathways, is critically dependent on the antigen-presenting cell (APC) and elicits effector responses dominated by recipient T cells. In allograft rejection, the engagement of recipient and donor cells results in recruitment of T-helper (Th) cells of the Th1 and Th17 lineage to the graft. In cases in which the alloresponse is dominated by regulatory T cells (Tregs), rejection can be prevented and the allograft tolerated with minimum or no immunosuppression. Here, we review the pathways of allorecognition that underlie CAD and the T-cell effector phenotypes elicited as part of the alloresponse. Future therapies including depletion of donor-reactive lymphocytes, costimulation blockade, negative vaccination using dendritic cell subtypes, and Treg therapy are inferred from an understanding of these mechanisms of allograft rejection.  相似文献   
58.

Background

After a brain biopsy, the genetic analysis can fail because of insufficient material, extensive tumor necrosis, and formalin fixation under conditions that adversely affected the quality of the DNA or because the assay result was indeterminant. The freezing of fresh tumor tissue at surgery could greatly improve the success of DNA extraction and methyl guanine methyl transferase (MGMT) promoter methylation testing. The concentration of the DNA samples can also be improved from a withdrawal in an area with a high probability of neoplastic cells.

Methods

The present study reports the results of ten frameless image-guided intracranial needle biopsies from April 2008 until February 2009, among a total of 28 frameless neuronavigation brain biopsy performed from May 2007 to February 2009. The protocol sampling provided withdrawal specimens correlated with neuroimaging characteristics of the lesions. The molecular determination of MGMT promoter was assessed with the nested methylation-specific polymerase chain reaction on fresh or cryopreserved needle bioptic tissue.

Results

The genetic characterization was feasible in all the bioptic samples. The MGMT promoter was methylated in six patients, including a brain infection. The image-guided trajectory of the biopsy and the intraoperative frozen section increased the diagnostic yield.

Conclusions

To the best of the authors' knowledge, this is the first report with the MGMT promoter status analysis on needle bioptic fresh tissue. In the future, the availability of the molecular genetic characterization of a brain tumor before open surgery will provide important information for the optimal treatment.  相似文献   
59.

Objective

Frey's syndrome is a frequent sequela of parotidectomy, causing facial sweating and flushing because of gustatory stimuli. Although botulinum toxin type A has become first-line therapy for Frey's syndrome, some patients become resistant. In this study, we investigated whether another serotype, botulinum toxin type B, might be an effective alternative.

Study Design

Case series with planned data collection.

Setting

Otolaryngology department in a university hospital.

Subjects and Methods

Seven patients aged 30 to 68 years, with severe Frey's syndrome, underwent the Minor test and had 80 U of botulinum toxin type B per cm2 (mean total dose, 2354 U) injected intracutaneously in the mapped area of gustatory sweating. All patients were followed up for 12 months.

Results

One month after treatment, six of the seven patients reported that gustatory sweating and flushing had resolved, and, in the remaining patient, these symptoms had decreased. The Minor test confirmed a significant improvement. The subjective benefits remained stable for six months in four patients and for nine months in the remaining three patients; 12 months after treatment, all patients still reported some improvement.

Conclusion

Botulinum toxin type B afforded symptomatic relief in a small sample of patients with Frey's syndrome and might be considered a potential alternative to botulinum toxin type A.  相似文献   
60.
Most of the histologic studies found in the literature on the peri-implant soft tissues have been done in animals and usually have been confined to mandibular implants fitted with healing or standard abutments. Few studies have investigated human peri-implant soft tissues. Moreover, the structure and dimensions of the peri-implant soft tissues in immediately loaded implants have not been investigated in depth. Human histologic data are valuable to validate animal models. This histologic and histomorphometric study evaluated the peri-implant soft tissues around three immediately loaded implants in humans. The implants were retrieved using a trephine and treated to obtain thin, ground sections. The sulcular epithelium was composed of approximately four to five layers of parakeratinized epithelial cells and had a length of approximately 1.2 to 1.3 mm. The junctional epithelium was composed of approximately three to four layers of epithelial cells and had a length of approximately 1.0 to 1.5 mm. Connective tissue attachment had a width of between 400 and 800 μm. Peri-implant collagen fibers, in the form of bundles (1- to 5-μm thick), began at the crestal bone and were oriented perpendicular to the abutment surface until 200 μm from the surface, where they became parallel running in several directions. Collagen fibers appeared to form a three-dimensional network around the abutment. No acute or chronic inflammatory cell infiltrate was present. Collagen fibers oriented in a perpendicular manner and in direct contact with the abutment surface were not observed in any of the specimens. This differentiated network of fibers may have clinical relevance as a mechanical protection of the underlying bone. These human histologic data are extremely valuable to validate and confirm those obtained from studies performed on animal models. Moreover, immediate loading of the implants did not compromise soft tissue integration.  相似文献   
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