SEARCH · PubMed Health

Results for “Dissection”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 865 records · Page 48Linked to original sources

PubMed2000

[Water-jet dissection in parotid surgery--initial clinical results].

INTRODUCTION: The most frequent complication following parotidectomies is postoperative facial nerve dysfunction. In animal experiment we successfully studied the technique of water-jet-dissection for safe and functional preservation in facial nerve dissection in parotid gland surgery. The aim of the present study was to evaluate our animal experiments clinically. METHODS: Until November '99 ten patients with benign parotid gland tumors (4 female, 6 male, age 32-77 years) underwent lateral or latero-segmental parotidectomies using water-jet-dissection ("Hydro-Jet", Andreas Pein Medizintechnik GmbH, Schwerin, Germany). All operations were performed under permanent intraoperative facial nerve monitoring ("Neurosign 100", Fa. Inomed, Tenningen, Germany). The postoperative facial nerve function was measured daily by the House-Brackmann and Stennert-Paresis-Index for at least one week. RESULTS: A quick parotid gland and safe facial nerve dissection could be performed in all operations using the 120 microns-nozzle with effective working pressures from 30-50 bar. In addition strong connective tissue fibers were transected with scissors. Intraoperative facial nerve lesions did not occur and cardiopulmonary complications due to eventual cutting-fluid-resorption were not seen. After surgery all patients had a normal facial nerve function. DISCUSSION: The results of our studies showed that the technique of water-jet-dissection provides safe facial nerve dissection and preservation during parotid gland surgery. CONCLUSIONS: The tissue selective cutting qualities of the new surgical method are an excellent alternative compared to standard dissection methods in parotid surgery.

Adult↗

PubMed2004

[Long-term hemodynamic compromise in internal carotid artery dissection: quantitative blood volume flow evaluation using 2D Cine phase-contrast MR imaging].

PURPOSE: To use the magnetic resonance (MR) phase-contrast technique as a non-invasive method to determine blood volume flow in internal carotid artery (ICA) dissection, which has variable initial volume flow reduction and long term hemodynamic compromise. ICA dissection can lead to partial or complete recanalization or persistent occlusion, and strong clinical motivation exists for reliable assessment of the blood flow, in particular blood volume flow, in the carotid artery circulation after ICA dissection. MATERIALS AND METHODS: Blood volume flow in the carotid artery circulation was quantified in 28 patients with unilateral ICA dissection and 20 age-matched normal controls. Blood volume flow was measured in the ICAs and the common carotid arteries (CCAs) using 2D cine phase-contrast MR imaging. Final measurements were performed until after at least 6 months the hemodynamic compromise showed no changes by ultrasound and MRA. RESULTS: In long term follow up, 11/28 patients demonstrated remaining vessel occlusion, 10/28 partial and 7/28 complete recanalizations. Patients with ICA occlusion showed a significant contralateral volume flow increase (mean 56 %, p < 0.001) in comparison to normal controls. Patients with partial recanalization demonstrated volume flow rates between 24 ml/min and 188 ml/min in the dissected ICA and a less but significant (p < 0.001) increase in the contralateral volume flow. In patients with complete recanalization, normal volume flow conditions were found for both ICAs and CCAs. CONCLUSION: In ICA dissection, quantitative volume flow determination using 2D cine phase-contrast MR imaging is helpful in the initial assessment and long term follow-up of hemodynamic compromise. ICA dissection demonstrated a partial or complete recanalization in nearly (2/3) of the investigated patients and a persisting vessel occlusion in little more than (1/3). Compensatory contralateral increase in volume flow was found.

Adult↗

PubMed2005

Endovascular treatment of obstructive iliac artery dissections.

PURPOSE: To report our results from a study of the endovascular treatment of flow restricting chronic atherosclerotic or catheter-induced segmental iliac artery dissections with bare stents. MATERIAL AND METHODS: Thirty symptomatic patients with 32 lesions, including chronic atherosclerotic (n = 21) and catheter-induced (n = 11) segmental arterial dissections, were treated with primary stenting. The common iliac artery was involved in 19 lesions and the external iliac artery in the remaining 13. Two patients had two lesions in the same vessel. Technical success was defined as restoration of the smooth contoured luminal patency with no more than 20% residual stenosis in diameter in atherosclerotic dissections associated with plaque formation or total obliteration of the false lumen in catheter-induced dissections. Complete relief of, or marked improvements in, presenting symptoms, or at least single category improvement, was assessed for clinical success. RESULTS: Technical success rate was 100%. No procedure-related complications such as distal emboli or early occlusions were observed. Complete symptom relief was achieved in all patients with catheter-induced dissection and in all but three cases with chronic spontaneous atherosclerotic dissection. In two cases, occlusion of the stents occurred during the follow-up period. Clinical and radiological mean follow-up for 24 months (range 3-55) revealed patency of all other stented segments. Cumulative primary patency rate was 97% over 12 months and 90% over 24 months. CONCLUSION: Endovascular treatment of chronic atherosclerotic and catheter-induced short obstructive iliac arterial dissections with bare stents is safe and effective. Patency of the diseased arterial segment with a smooth lumen can be sustained for an extensive period.

Adult↗

PubMed2006

Modified and bilateral retroperitoneal lymph node dissection for testicular cancer: peri- and postoperative complications and therapeutic outcome.

OBJECTIVE: To characterize surgical invasiveness and morbidity and to verify therapeutic efficacy, we reviewed perioperative and postoperative courses and therapeutic outcomes of patients who underwent retroperitoneal lymph node dissection (RPLND) for testicular germ cell cancers. METHODS: The study included 31 patients who underwent retroperitoneal lymph node dissection. A modified template was used if retroperitoneal metastasis was limited to the areas below the level of the renal hilus and above the level of the inferior mesenteric artery (IMA). Perioperative and postoperative courses and complications were reviewed as well as therapeutic outcomes. RESULTS: Overall, 27 perioperative and postoperative complications were observed in 15 patients (48.4%). Superficial surgical site infection and paralytic ileus were seen most frequently. All of them were resolved without special additional treatments; however, patients who underwent retrocrural dissection had a tendency to have severe symptomatic complications such as chylothorax, phrenic nerve palsy and orthostatic hypotension. Antegrade ejaculation was preserved in 94.1% of patients with modified template dissection, whereas no patients with additional dissection below the level of the IMA had the function preserved. One patient (3.2%) developed a postoperative recurrent disease in the retroperitoneum, which was outside the dissection field, as well as in the mediastinum. CONCLUSIONS: Although RLND had high morbidity, most peri- and postoperative complications were manageable conservatively. Modified template dissection enabled patients to preserve antegrade ejaculation without compromising its therapeutic efficacy, if the disease extension allowed us to use the template.

Adolescent↗

PubMed1999

Anatomic study of the lateral femoral cutaneous nerve with respect to the ilioinguinal surgical dissection.

OBJECTIVE: To report on the anatomic variations of the lateral femoral cutaneous nerve with respect to the ilioinguinal surgical dissection. DESIGN: Cadaveric anatomic study. PATIENTS/PARTICIPANTS: Sixty-eight ilioinguinal dissections performed in fifty cadavers. INTERVENTION: The lateral femoral cutaneous nerve was identified, and certain location variables were recorded. MAIN OUTCOME MEASURE: The distance in millimeters from the medial edge of the anterior superior iliac spine (ASIS), whether the nerve was lateral or medial to the ASIS, and the layer in which the nerve crossed the dissection. RESULTS: In seven dissections, the nerve was twenty-one to twenty-five millimeters medial to the ASIS; in ten dissections, the nerve was twenty-six to thirty millimeters from the ASIS; and in fourteen dissections, the nerve was more than thirty millimeters medial to the superior border of the ASIS. The average medial distance from the ASIS was 20.4 millimeters, with a range of three to forty-six millimeters. In no specimen did the nerve pass lateral to the ASIS. The lateral femoral cutaneous nerve was found to lie anterior to the iliopsoas muscle in all specimens. CONCLUSION: The course of the lateral femoral cutaneous nerve is highly variable; the nerve was most commonly found at ten to fifteen millimeters from the ASIS and as far medially as forty-six millimeters. When using the illioinguinal surgical approach, if the lateral femoral cutaneous nerve is not encountered immediately adjacent to the ASIS, dissection up to five centimeters medial to the ASIS may be necessary to locate the nerve.

Cadaver↗

PubMed2001

Extraperitoneal laparoscopic para-aortic lymph node dissection for early stage nonseminomatous germ cell tumors of the testis with introduction of a nerve sparing technique: description and results.

PURPOSE: The extraperitoneal approach is well suited to urological surgery. Transperitoneal laparoscopic para-aortic lymph node dissection has been reported with good results for early stage nonseminomatous germ cell tumor of the testis. We report our current experience with laparoscopic para-aortic lymph node dissection using a new extraperitoneal approach. MATERIALS AND METHODS: The technique consists of an internal iliac extraperitoneal approach and complete unilateral modified laparoscopic para-aortic lymph node dissection. We assessed 25 patients with clinical stage I (20) or IIA (5) testicular nonseminomatous germ cell tumor who underwent this technique, including left and right lymphadenectomy in 13 and 12, respectively. In addition, nerve sparing dissection was performed in the last 12 cases. RESULTS: An average of 9.8 (range 3 to 19) and 17. 7 (range 5 to 29) lymph nodes were dissected on the right and left sides, respectively. No intraoperative or postoperative complications developed that required laparotomy. Average operative time was 3 hours 50 minutes (range 3 to 5 hours). Average hospital stay was 1.2 days (range 1 to 3). Results were positive in 10 patients who were given platinum based chemotherapy. At close followup of 15 months no late adverse effects or recurrence was observed. CONCLUSIONS: Although a larger experience and longer followup are required, extraperitoneal laparoscopy is a safe, effective and well suited method of diagnostic para-aortic lymph node dissection for early stage testicular nonseminomatous germ cell tumor. The specific advantages of this approach are no blind trocar insertion or bowel contact and ability to perform nerve sparing dissection. Moreover, it is cost-effective since only 3 trocars are necessary and recovery is rapid.

Adult↗

PubMed1999

Modified neck dissection for metastatic nonseminomatous testicular carcinoma.

OBJECTIVE: To examine the role of neck dissection in the treatment of metastatic stage 3 nonseminomatous germ-cell tumors (NSGCTs) of testicular origin. METHOD: A retrospective review was made of 45 patients with metastatic NSGCT who underwent 48 unilateral and 3 bilateral neck dissections. Only level III-VI nodes were dissected, often with concomitant or staged mediastinal dissection, thoracotomy, and/or retroperitoneal node dissection. Occasionally, resection of the clavicle, jugular vein, or subclavian artery, or a combination of these, was required to eradicate the disease. RESULTS: There were only four instances of recurrence in dissected necks. There was one case of dedifferentiation of mature teratoma to adenocarcinoma Patients who were followed for a mean period of 32 months had a disease-free survival of 72%. Prognosis for patients with stage 3 disease but negative preoperative tumor markers (alpha-fetoprotein and human chorionic gonadotropin) was excellent, with 97% of these patients having no evidence of disease at follow-up. Factors having a negative impact on survival included positive tumor markers, elements of germ-cell cancer in excised nodes, and a neck mass that represents late relapse of disease. CONCLUSION: Modified neck dissection has a demonstrated role in the treatment of metastatic NSGCT. It prevents reversion of mature teratoma to malignant germ cell tumor with minimal morbidity. Aggressive resection of disease is indicated, often in conjunction with thoracic surgery, to eradicate disease extending into the chest. There is an excellent prognosis in patients with negative preoperative serologic tumor markers.

Adult↗

PubMed1994

The effect of lasers, electrocautery, and sharp dissection on cutaneous flaps.

This study evaluated the technical ease and wound-healing response of cutaneous flaps constructed on dogs using Nd:YAG laser, CO2 laser, electrocautery, and sharp dissection. Four flaps were constructed on the dorsum of 16 dogs using each of the four modalities. Parameters examined included drainage after both 48 hours and 1 week, time of dissection, bursting strength, and semiquantitative assessments of fibroblast, polymorphonuclear leukocyte, monocyte, and collagen content. Significantly less time was required to construct flaps with electrocautery as compared with CO2 laser, Nd:YAG laser, and sharp dissection (15 versus 18, 20, and 26 minutes, respectively; p < 0.01). Significantly fewer suture ligatures were necessary to obtain hemostasis for electrocautery, CO2 laser, and Nd:YAG laser as compared with sharp dissection (0, 2, and 2 versus 15 sutures, respectively; p < 0.01). Drainage was significantly less for flaps constructed using sharp dissection as compared with both CO2 and Nd:YAG lasers at 48 hours (12 versus 26 cc, p < 0.01, and 20 cc, p < 0.05, respectively). Significantly less drainage was observed after 48 hours for flaps created using electrocautery as compared with CO2 laser (14 versus 26 cc; p < 0.05). Bursting strength of flaps constructed using sharp dissection was significantly greater than that of those constructed using electrocautery, Nd:YAG laser, and CO2 laser (1086 versus 638 gm, p < 0.05, 714 gm, and 571 gm, p < 0.01, respectively). Semiquantitative histologic evaluation revealed a higher collagen content and fibroblast infiltration and less polymorphonuclear leukocyte infiltration in wounds created using sharp dissection as compared with CO2 laser, Nd:YAG laser, and electrocautery.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1999

Predictors of proximal aortic dissection at the time of aortic valve replacement.

BACKGROUND: Type I aortic dissection develops in 0.6% of patients late after aortic valve replacement (AVR), and 13% of patients with type I aortic dissections have a history of AVR. Predictors of aortic dissection at AVR, however, have not been characterized. METHODS AND RESULTS: A study group of 33 patients with type I aortic dissection had aortic surgery 49+/-55 months after routine AVR. A group of 101 controls, who did not have morphological progression of aortic diameters >/=6 years after AVR, was used to identify predictors of postsurgical dissection. Multivariate analysis identified aortic regurgitation (P<0.002) and fragility (P<0.001) or thinning of the aortic wall (P<0.007) at AVR as predictors, associated with a 14%, 22%, and 7% probability of late aortic dissection, respectively. Clamping times, types of valve prostheses, concomitant coronary artery bypass grafting, and mean ascending aortic diameters of 43+/-10 mm at AVR did not predict late dissection. A separate analysis of 29 nondissecting aneurysms of the ascending aorta developing 104+/-64 months after routine AVR revealed younger age at AVR (P<0.003) and congenitally bicuspid aortic valves (P<0.03) as predictors of late aneurysm formation. CONCLUSIONS: Aortic regurgitation combined with fragile and thinned aortic walls in patients with moderate aortic dilation may reflect aortic root disease, with a high risk for postsurgical aortic sequelae if it is treated incompletely by isolated valve replacement.

Adult↗

PubMed1994

Cardiac tamponade complicating proximal aortic dissection. Is pericardiocentesis harmful?

BACKGROUND: Cardiac tamponade frequently complicates acute proximal aortic dissection and is one of the most common causes of death from aortic dissection. Well-defined strategies for the management of acute aortic dissection now exist; however, little is known about how best to manage the hemopericardium that may complicate it. METHODS AND RESULTS: Using a computer-based review, we retrospectively identified 10 patients presenting to our hospital over a 13-year period who were diagnosed with both aortic dissection and cardiac tamponade. All 10 had proximal dissections. Three of the 10 presented as the sudden onset of fatal electromechanical dissociation, 6 presented with hypotension, and 1 was normotensive on presentation. Of the 7 hypotensive or normotensive patients diagnosed with cardiac tamponade, 4 underwent successful pericardiocentesis while awaiting surgery. At time intervals of 5 to 40 minutes after their pericardiocenteses, 3 of the 4 patients experienced sudden onset of electromechanical dissociation and death; the fourth patient survived and underwent surgical repair. Of the 3 hypotensive or normotensive patients who had either no pericardiocentesis or an unsuccessful pericardiocentesis, all 3 underwent successful surgical repair and survived. CONCLUSIONS: In this study, patients with an aortic dissection complicated by cardiac tamponade have an early mortality of 60%. While 3 of the 10 died from electromechanical dissociation immediately upon presentation, the 3 other deaths all occurred shortly after successful pericardiocentesis, a procedure undertaken to stabilize them. While the number of patients in this series is small, the observations do raise the possibility that in patients with cardiac tamponade complicating aortic dissection pericardiocentesis could be harmful rather than beneficial. Possible mechanisms for why the performance of pericardiocentesis might destabilize such patients are proposed.

Aged↗

PubMed2000

Isolated dissection of the celiac artery--a case report.

Isolated arterial dissection, which occurs with the absence of aortic dissection, has been reported in carotid and renal arteries but rarely in visceral arteries. A case of isolated celiac artery dissection is reported here. A healthy 58-year-old man experienced sudden upper abdominal pain, which continued for several days. A body computed tomogram (CT) showed a multiple low-density wedge-shaped area in the spleen, which was diagnosed as splenic infarction, and an aneurysm with thrombus in the celiac artery. A selective angiogram showed dilatation of the celiac artery with wall irregularity, and proximal occlusion of the hepatic artery. The distal hepatic artery was fed by collateral arteries from the superior mesenteric artery. Splenic infarction was probably due to the embolism from the thrombus in the dissected celiac artery. The absence of other vascular lesions and causes or risks for the arterial dissection would suggest the occurrence of spontaneous dissection. The dissection of visceral arteries should be considered in diagnosing acute abdominal pain.

Abdominal Pain↗

PubMed2006

Gene expression in acute Stanford type A dissection: a comparative microarray study.

BACKGROUND: We compared gene expression profiles in acutely dissected aorta with those in normal control aorta. MATERIALS AND METHODS: Ascending aorta specimen from patients with an acute Stanford A-dissection were taken during surgery and compared with those from normal ascending aorta from multiorgan donors using the BD Atlas Human1.2 Array I, BD Atlas Human Cardiovascular Array and the Affymetrix HG-U133A GeneChip. For analysis only genes with strong signals of more than 70 percent of the mean signal of all spots on the array were accepted as being expressed. Quantitative real-time polymerase chain reaction (RT-PCR) was used to confirm regulation of expression of a subset of 24 genes known to be involved in aortic structure and function. RESULTS: According to our definition expression profiling of aorta tissue specimens revealed an expression of 19.1% to 23.5% of the genes listed on the arrays. Of those 15.7% to 28.9% were differently expressed in dissected and control aorta specimens. Several genes that encode for extracellular matrix components such as collagen IV alpha2 and -alpha5, collagen VI alpha3, collagen XIV alpha1, collagen XVIII alpha1 and elastin were down-regulated in aortic dissection, whereas levels of matrix metalloproteinases-11, -14 and -19 were increased. Some genes coding for cell to cell adhesion, cell to matrix signaling (e.g., polycystin1 and -2), cytoskeleton, as well as several myofibrillar genes (e.g., alpha-actinin, tropomyosin, gelsolin) were found to be down-regulated. Not surprisingly, some genes associated with chronic inflammation such as interleukin -2, -6 and -8, were up-regulated in dissection. CONCLUSION: Our results demonstrate the complexity of the dissecting process on a molecular level. Genes coding for the integrity and strength of the aortic wall were down-regulated whereas components of inflammatory response were up-regulated. Altered patterns of gene expression indicate a pre-existing structural failure, which is probably a consequence of insufficient remodeling of the aortic wall resulting in further aortic dissection.

Journal Article↗

PubMed2004

Clinical meaning of uncomplicated coronary dissections after stent implantation.

OBJECTIVE: To assess the influence of uncomplicated coronary dissections in the incidence of target vessel revascularization and cardiovascular events after 1 year. METHODS: Patients treated from June 1996 to December 2000, with data prospectively collected and uncomplicated dissections (G1, n=36), were compared with those patients without dissections (G2, n=871). Data were assessed with SPSS 8.0 statistical software, the outcomes were compared with the Kaplan-Meier curve, and the significance level was assessed using the log-rank test. RESULTS: Clinical features were similar in both groups: G1 had lower mean reference diameters (P<0.0001), a greater number of patients with type C lesions (P=0.01), a lower final lumen diameter at the end of the procedure (P=0.003), and a greater balloon/artery ratio (P<0.0001). In the multivariate analysis, only the reference diameter and the artery/balloon ratio were independently associated with the presence of residual dissections. No statistically significant difference existed in the incidence of revascularization of the target vessel and major cardiovascular events, at 1-year clinical follow-up, between the 2 groups of patients. Predictors of adverse clinical events at 1 year were the reference diameter, lesion extension, and residual stenosis, rather than the presence of residual dissection. CONCLUSION: Uncomplicated residual dissections after coronary stents are associated with narrower vessels and a higher balloon/artery ratio. Residual dissections are not associated with worse outcomes at 1-year clinical follow-up.

Angioplasty, Balloon, Coronary↗

PubMed1998

Anterior labroligamentous structures of the glenohumeral joint: correlation of MR arthrography and anatomic dissection in cadavers.

OBJECTIVE: The purpose of this study was to establish the accuracy of MR arthrography in depicting the morphology of the glenohumeral ligaments and the superior portion of the glenoid labrum. MATERIALS AND METHODS: Findings on MR arthrography and those derived from careful dissection of gross specimens were compared in 15 cadaver shoulders, focusing on the morphology and size of the superior and middle glenohumeral ligaments and the morphology of the inferior glenohumeral ligament. The frequencies of sublabral recess and sublabral foramen seen on MR arthrography and at anatomic dissection were also compared. RESULTS: For the superior and middle glenohumeral ligaments, moderate correlation of size was found between measurements made on MR arthrograms and at anatomic dissection, with the Spearman's rank correlation coefficient calculated as .69990 and .71133, respectively. Morphologic descriptions of the inferior glenohumeral ligament based on MR arthrography and on anatomic dissection also showed good association (Cohen's kappa = .8936). Dissection revealed that the sublabral recess was present in 11 specimens. Of these, 10 recesses were identified on MR arthrograms. MR arthrography also revealed a sublabral recess that was not found at dissection. Four sublabral foramina were identified by both MR arthrography and dissection, and two were revealed only by MR arthrography. CONCLUSION: MR arthrography is useful in the evaluation of the glenohumeral ligaments and the superior portion of the labrum. Anatomic variations of these anterior intraarticular structures can be accurately shown by MR arthrography. In addition, estimation of the size of glenohumeral ligaments can be achieved with acceptable accuracy on MR arthrograms.

Aged↗

PubMed1987

Comparison of surface diameters and dissected diameters of bovine ovarian follicles.

Comparisons were made between diameters of 54 bovine follicles greater than 5.9 mm from 32 pairs of ovaries measured on the ovarian surface and diameters of the same follicles subsequently dissected from the ovaries. Seventy-eight percent of follicles measured on the ovarian surface were within 1.9 mm of the size measured after dissection. The remaining 22% of follicles measured on the surface had diameters recorded that were 2.0 to 3.9 mm different than their diameter after dissection. Surface diameter tended to underestimate dissected diameter for small follicles (less than 8.0 mm) and to overestimate dissected diameter for large (greater than or equal to 12.0 mm) follicles. The correlation coefficient between surface and dissected follicular diameters was .83. We conclude that measuring the diameter of the largest follicles on the ovarian surface and after dissection yield approximately equivalent results.

Animals↗

PubMed1992

Cervico-thoraco-abdominal (3-field) lymph node dissection for carcinoma in the thoracic esophagus.

The efficacy of an extended radical lymph node dissection for carcinoma in the thoracic esophagus is controversial. Results of a multivariate analysis using clinical data from 127 cases collected from 1982 to 1988 are reported. Twenty-seven of these patients underwent an extended radical (cervico-thoraco-abdominal: 3 fields) lymph node dissection which was recently developed in Japan, while others underwent a standard (thoraco-abdominal: 2 fields) lymph node dissection. They all had a locally-curative resection of the tumor through a right thoracotomy. In this study, 13 factors commonly affecting prognosis were examined: sex, age, cancer location, tumor length, radiographic type, depth of invasion, lymph node metastasis, tumor differentiation, postoperative radiotherapy, chemotherapy, operative risk, postoperative complications, and 3-field or 2-field dissection. Based on the survival-rate curves using Kaplan-Meier's statistics, the 3-field dissection was superior to the 2-field dissection. Moreover, when other prognostic factors were adjusted using Cox's proportional hazards general linear model, the same result was obtained from survival-rate curves. From this analysis, it can be concluded that a 3-field dissection is a better approach for management of carcinoma in the thoracic esophagus.

Abdomen↗

PubMed2001

Transcerebellomedullary fissure approach with special reference to methods of dissecting the fissure.

OBJECT: The purpose of the present study was to refine the transcerebellomedullary fissure approach to the fourth ventricle and to clarify the optimal method of dissecting the fissure to obtain an appropriate operative view without splitting the inferior vermis. METHODS: The authors studied the microsurgical anatomy by using formalin-fixed specimens to determine the most appropriate method of dissecting the cerebellomedullary fissure. While dissecting the spaces around the tonsils and making incisions in the ventricle roof, the procedures used to expose each ventricle wall were studied. Based on their findings, the authors adopted the best approach for use in 19 cases of fourth ventricle tumor. The fissure was further separated into two slit spaces on each side: namely the uvulotonsillar and medullotonsillar spaces. The floor of the fissure was composed of the tela choroidea, inferior medullary velum, and lateral recess, which form the ventricle roof. In this approach, the authors first dissected the spaces around the tonsils and then incised the taenia with or without the posterior margin of the lateral recess. These precise dissections allowed for easy retraction of the tonsil(s) and uvula and provided a sufficient view of the ventricle wall such that the deep aqueductal region and the lateral region around the lateral recess could be seen without splitting the vermis. The dissecting method could be divided into three different types, including extensive (aqueduct), lateral wall, and lateral recess, depending on the location of the ventricle wall and the extent of surgical exposure required. CONCLUSIONS: When the fissure is appropriately and completely opened, the approach provides a sufficient operative view without splitting the vermis. Two key principles of this opening method are sufficient dissection of the spaces around the tonsil(s) and an incision of the appropriate portions of the ventricle roof. The taenia(e) with or without the posterior margin of the lateral recess(es) should be incised.

Adolescent↗

PubMedDate not supplied

The complete hilar-mediastinal lymph node dissection.

Starting from Cahan's "radical pneumonectomy" and "radical lobectomy", mediastinal lymph node dissection was introduced in Japan by Ishikawa and survival results analyzed by Naruke. Japanese Lung Cancer Society (JLCS) introduced Naruke's lymph node map to standardizing dissection. Upper mediastinum, subcarinal, interlobar and upper lobar lymph nodes are to be dissected for tumors located in the right upper lobe, and the same areas in the case of middle lobe. In tumors of the lower right lobe, also nodes of the lower mediastinum should be dissected. When the tumor is in the left upper lobe, upper mediastinum (except pre and paratracheal lymph nodes), subcarinal, interlobar and lobar nodes should be dissected. Finally, in left lower tumors, lower mediastinum is to be dissected. Super-radical dissection is performed through a median sternotomy to reach pre and paratracheal nodes in tumors affecting the left upper lobe.

Humans↗