Transgenerational impacts of herbivory and inbreeding on reproductive output in Solanum carolinense.

PREMISE: Plant maternal effects on offspring phenotypes are well documented. However, little is known about how herbivory on maternal plants affects offspring fitness. Furthermore, while inbreeding is known to reduce plant reproductive output, previous studies have not explored whether and how such effects may extend across generations. Here, we addressed the transgenerational consequences of herbivory and maternal plant inbreeding on the reproduction of Solanum carolinense offspring. METHODS: Manduca sexta caterpillars were used to inflict weekly damage on inbred and outbred S. carolinense maternal plants. Cross-pollinations were performed by hand to produce seed from herbivore-damaged outbred plants, herbivore-damaged inbred plants, undamaged outbred plants, and undamaged inbred plants. The resulting seeds were grown in the greenhouse to assess emergence rate and flower production in the absence of herbivores. We also grew offspring in the field to examine reproductive output under natural conditions. RESULTS: We found transgenerational effects of herbivory and maternal plant inbreeding on seedling emergence and reproductive output. Offspring of herbivore-damaged plants had greater emergence, flowered earlier, and produced more flowers and seeds than offspring of undamaged plants. Offspring of outbred maternal plants also had greater seedling emergence and reproductive output than offspring of inbred maternal plants, even though all offspring were outbred. Moreover, the effects of maternal plant inbreeding were more severe when plant offspring were grown in field conditions. CONCLUSIONS: This study demonstrates that both herbivory and inbreeding have fitness consequences that extend across generations even in outbred progeny.

Long-term clinical results of thoracoscopic Heller's myotomy in the treatment of achalasia.

OBJECTIVE: The aim of this study is to review the immediate and long-term results of video-imaged thoracoscopic Heller's myotomy (THM). METHODS: All patients undergoing THM by a single surgeon at one institution were analysed. Follow-up was conducted using a structured questionnaire and oesophageal manometry and/or 24h pH monitoring were undertaken when clinically indicated. RESULTS: Fifty-six consecutive patients (32 males, 24 females, mean age 45+/-18.7 years) suffering from grade 4 dysphagia underwent THM between January 1992 and March 2006. Preoperative mean lower oesophageal sphincter (LOS) pressure was 38.4+/-10.6 mmHg. Eighteen patients (32.1%) had undergone previous pneumatic dilatations. There were no hospital deaths. Oesophageal perforation occurred in two patients; one repaired thoracoscopically and one at thoracotomy. Mean hospital stay was 4+/-1.37 days. At mean follow-up of 5.9+/-4.66 years, freedom from any reintervention was 87% (49/56). Twenty-nine patients (52%) were asymptomatic. In patients with residual or recurrent symptoms (n=27), their severity was significantly reduced from the preoperative period (dysphagia score 1.37+/-0.77 vs 4.00+/-0; p<0.001). Seven patients (12.5%) with troublesome residual or recurrent grade 3-4 dysphagia underwent repeat oesophageal manometric study, showing a mean reduction in LOS pressure from their baseline values of 46.8+/-6.1-30.0+/-5.4 mmHg (p<0.001). Of these patients, three patients with grade 4 dysphagia were reoperated: one open Heller's myotomy and two by cardia resection. Eleven patients complained of troublesome postoperative heartburn; distal oesophageal acid exposure was shown to be abnormal in nine patients (16.9%) and all were successfully managed with medical therapy. CONCLUSION: The results of thoracoscopic treatment for achalasia are at least equivalent to historical outcomes obtained with open surgery but the patient is spared major thoracotomy or the acid reflux associated with a laparoscopic approach.

The VATS lobectomist: analysis of costs and alterations in the traditional surgical working pattern in the modern surgical unit.

It is beyond the scope of this article to review the advantages of VATS lobectomy, but the data in support of this technique are increasing progressively. There is excellent evidence to support the oncologic equivalence and safety profile as compared with open thoracotomy, and data that demonstrate the reduced pain associated with VATS resection. Also, reduction in immune disturbance provides a tantalizing glimpse of one additional potential modality of benefit for less traumatic surgery. Unfortunately, in the economic world, equivalence, preferably with less cost, is the test applied. Whatever the societal benefit of improved quality of life following surgery, this has no cost benefit attached. From the foregoing discussion one can conclude that VATS lobectomy is no more costly than open resection and does generate additional hospital beds. The authors remain uncertain as to the preferred form of VATS lobectomy but it seems that the reduced trauma of the endoscopic procedure is associated with more benefit in terms of shorter hospitalization albeit at the cost of some increase in operating time. VATS techniques and lobectomy sit comfortably within the structure of any thoracic unit requiring little adjustment to established process. It is likely that ultimately 30% or thereabouts of major pulmonary resection will be undertaken using this technique and that VATS interventions will aid patient assessment regardless of stage or ultimate intended therapy. Competency and responsible use remain paramount considerations.

Immunologic and stress responses following video-assisted thoracic surgery and open pulmonary lobectomy in early stage lung cancer.

Conventional open major surgery evokes an injury response involving endocrine, neural, and immunologic mechanisms. The immunologic responses are characterized by release of cytokines, inflammatory mediators, and acute-phase proteins and by adverse disturbances in immune cell function. The use of a minimal access approach strategy is associated with a significant reduction in the cytokine response, as exemplified by reduced interleukin-6 levels and a corresponding reduction in acute-phase protein generation with reduced C-reactive protein levels. Circulating immune cell function and numbers also are better preserved. These changes have been demonstrated in comparing open with video-assisted thoracoscopic surgery (VATS) lobectomy and, together with further investigation into local immune function, may offer some insight into the excellent survival data reported for VATS resection of stage I non-small cell lung cancer.

Microlobectomy: A Novel Form of Endoscopic Lobectomy.

OBJECTIVE: Microlobectomy is a novel form of videoscopic-assisted thoracic surgery lobectomy. Strict inclusion criteria consist of the following: no intercostal incisions greater than 5 mm, 12 mm subxiphoid port, subxiphoid removal of the specimen, total endoscopic technique with CO2 insufflation, vision through a 5-mm camera, stapling via the subxiphoid port, or with 5-mm stapling devices. METHODS: The combined early experiences of six hospitals from three countries were combined from September 2014 to May 2016. During that time, the study represents a consecutive cohort study of this technique. RESULTS: Seventy-two patients underwent microlobectomy. The median (range) age was 66 (27-82). Half of the patients were female. There were 48 right-sided resections and 24 on the left. There were four segmental resections and there was one right pneumonectomy. Four operations were performed robotically (with 8-mm intercostal incisions). The median (range) operative time was 180 (94-285) minutes and the blood loss was 118 (5-800) mL. There were three conversions to thoracotomy and two conversions to videoscopic-assisted thoracic surgery by means of an intercostal utility incision to complete the operation. The median (range) length of stay was 3 (1-44) days and 30 patients (42%) when home by day 2 and 16 patients (22%) were discharged on day 1. There were no deaths. Five patients (7%) had a prolonged airleak. There were no wound infections and there was one incisional hernia. CONCLUSIONS: We believe that microlobectomy is an interesting novel form of videoscopic-assisted thoracic surgery lobectomy and has several theoretical advantages. We have presented our early results and hope that this will stimulate others to investigate this type of videoscopic-assisted thoracic surgery lobectomy further.

Intranodal Palisaded Myofibroblastoma Masquerading as N2 Non-Small Cell Lung Carcinoma.

Intranodal palisaded myofibroblastoma is a rare and benign tumor that usually presents in the inguinal region. We report the case of a 68-year-old woman with a right paratracheal mass and right upper lobe non-small cell lung carcinoma initially staged as T1b N2 M0. After mediastinal staging, the right paratracheal mass was found to be an intranodal palisaded myofibroblastoma, which had caused erroneous upstaging of the lung carcinoma to N2 disease. This had the potential of leading to suboptimal treatment of the primary lung carcinoma if formal mediastinal staging had not been performed. To the best of our knowledge, this is the first report in the English literature of an intranodal palisaded myofibroblastoma occurring concurrently with lung cancer. This case highlights the importance of mediastinal staging in lung cancer. Mediastinoscopy remains the gold standard.

A Glomus Tumor With Recurrence and Malignant Transformation in the Chest Wall: A Cautionary Tale of Seeding?

Glomus tumors are rare tumors most often occurring in the extremities of the limbs. We report a unique case of a glomus tumor, originally arising in the paraspinal region, which was excised and subsequently recurred in the chest wall with malignant transformation. The recurrence is likely to have been caused by wound seeding. To the best of our knowledge, this is the first report in the English literature of a glomus tumor recurrence secondary to the notion of wound seeding.

Predictors of mortality in early surgical intervention for active native valve endocarditis and significance of antimicrobial therapy: a single-center experience.

BACKGROUND AND AIM OF THE STUDY: Cardiac surgery for active infective endocarditis remains a challenging and high-risk procedure. The outcome from early surgical intervention for active native valve endocarditis (ANVE) was studied, the aim being to identify significant predictors of mortality and the relationship between duration of preoperative antibiotics and outcome. METHODS: Between January 1996 and February 2002, 61 patients with ANVE underwent surgery within four weeks of diagnosis. Preoperatively, 29 patients received antibiotics for <2 weeks (group A), and 32 received antibiotics for 2-4 weeks (group B). The median follow up period was 37.4 months (range: 21-55 months). Data were collected retrospectively and analyzed. To determine factors related to mortality, Kaplan-Meier survival analysis was employed, utilizing log-rank statistics to identify evidence of significant differences between the groups. The relationship between the duration of preoperative antibiotics and morbidity was determined using chi-square and Fisher's Exact tests, as appropriate. RESULTS: Overall operative mortality was 14.8% (group A, 13.8%; group B, 15.6%). Rates of early and late prosthetic valve endocarditis were 1.8% and 1.9% (only in group B) respectively. The overall survival rate for the follow up period was 81.9%. Predictors of mortality were extensive infection (p = 0.01), poor left ventricular function (p <0.0001), progressive cardiac failure as an indication for surgery (p <0.0001), postoperative sepsis (p <0.0001), renal failure after surgery (p = 0.0002) and use of a bioprosthetic valve (p = 0.045). There were no significant inter-group differences for extensive infection (p = 1.00), postoperative sepsis (p = 1.00), reoperation (p = 1.00) and mortality (p = 1.00). CONCLUSION: In patients with ANVE, early aggressive surgical intervention before the onset of cardiac failure and spread of infection is warranted. The present data suggest that, in these patient groups, the duration of preoperative antibiotics had no significant influence on postoperative morbidity and mortality.

Endoscopic and endobronchial ultrasound real-time fine-needle aspiration for staging of the mediastinum in lung cancer.

Mediastinal lymph node metastases in patients with non-small cell lung cancer are a critical determinant of operability. Mediastinoscopy is invasive, requires general anesthesia, and carries appreciable morbidity. The development of minimally invasive techniques for the pathologic staging of lung cancer is important. We report a one-stop minimally invasive method for the pathologic diagnosis and staging of the majority of the mediastinum under conscious sedation using a novel prototype endobronchial ultrasound probe with a real-time fine-needle aspiration (FNA) facility in combination with conventional endoscopic ultrasound FNA.

Spontaneous rupture of the right hemidiaphragm after video-assisted lung volume reduction operation.

Lung volume reduction operation is an important therapeutic option in patients with advanced emphysema. We report a case of spontaneous rupture of the right diaphragm after a video-assisted thoracoscopic surgical procedure for emphysema. The pathophysiology of this complication is also discussed, along with practical points for perioperative management of emphysematous patients.

Long-term outcomes following VATS lobectomy for non-small cell bronchogenic carcinoma.

OBJECTIVES: Despite advantages regarding pain and muscle function, video-assisted thoracic surgery (VATS) lobectomy is infrequently performed and is particularly controversial in bronchogenic carcinoma. We have, therefore, reviewed our experience with VATS lobectomy for non-small cell lung cancer (NSCLC) in an attempt to define the long-term results of VATS lobectomy in this setting. METHODS: Patients were selected for surgery on the basis of clinical Stage I or II disease with routine use of thoracic/upper abdominal CT scanning and cervical mediastinoscopy. VATS resection was performed using the endoscopic hilar dissection technique. All related hilar nodes were cleared and supportative sampling of mediastinal stations beyond the reach of mediastinoscopy was undertaken. Perioperative data were collected prospectively and oncologic outcomes were assessed by 6 monthly census. RESULTS: One hundred and fifty eight patients (mean age 66 years) underwent 159 VATS lobectomies for NSCLC between May 1992 and December 2001. One patient underwent staged bilateral resections. Twenty further procedures were uneventfully converted to open thoracotomy (rate=11.2%). The median operation time was 130 min and median operative blood loss was 60 ml. The median postoperative stay was 6 days. One patient (0.6%) died following VATS resection from acute respiratory distress syndrome (ARDS). Two VATS resection patients died following discharge but within 30 days of surgery. Combined, inpatient and 30-day outpatient mortality was, therefore, 1.8%. The stage distribution for resected lesions was: Stage I, 117; II, 33 and III, 8. Mean follow-up was 38 months (range: 1-107). Tumour recurred in 36 patients presenting as local recurrence in the hilum or mediastinum in nine (25%), metastatic disease in 23 (63.9%) and unknown pattern in four (11.1%). Kaplan-Meier calculated probabilities of freedom from cancer related or associated death at 60 months were Stage I, 77.9%; II, 51.4% and III, 28.6%. CONCLUSION: VATS lobectomy is a safe procedure which is associated with a low probability for conversion to open thoracotomy. The patterns of cancer recurrence do not suggest inadequate local clearance while the long-term survival data for Stage I NSLC cases is encouraging. We believe that this technique should become the operation of choice for early stage NSCLC.

The application of capnography to differentiate peri-chest tube air leak from parenchymal leak following pulmonary surgery.

Prolonged air leak is a common complication of pulmonary resection. However, while a bubbling chest drain is commonly related to parenchymal air leakage, it may also be caused by air entering the pleural cavity via an incomplete seal of the tissues at the chest tube insertion site. Examination alone is not sufficient to guide the surgeon as to which of the above complications is responsible for drain bubbling. We describe a simple method, whereby a CO2 monitoring device is attached to the chest drain to determine whether the air loss observed is in fact due to a pulmonary air leak.

Histological evaluation of preoperative mediastinoscopy lymph node biopsies in non-small cell lung cancer.

INTRODUCTION: Despite the advent of PET scanning and endoscopic minimally invasive methods of sampling mediastinal lymph nodes, surgical assessment, particularly by mediastinoscopy, remains an important tool for staging non-small cell lung cancer. METHODS: We carried out a retrospective review of mediastinoscopic lymph node biopsies taken at The Royal Infirmary of Edinburgh between 1996 and 2006 and performed additional histological investigations on select cases. RESULTS: In total, 89/802 (11%) patients had a negative mediastinoscopy but final resection stage of N2/N3. Within this group, 41/89 (46%) patients had positive resection lymph nodes in stations potentially accessible to biopsy at mediastinoscopy. Of these, 30 (34%) patients had had the metastatic station sampled at mediastinoscopy. Further histopathological examination (multiple levels and pancytokeratin immunohistochemistry) of these original biopsies detected micrometastases in two cases, one of which, in retrospect, had been missed on the original section at the time of reporting. Isolated tumour cells were detected by immunohistochemistry in another two cases. CONCLUSIONS: Routine examination of additional levels and immunohistochemical staining of mediastinal lymph nodes biopsies is not required and would not improve the overall negative predictive value of the procedure.

Cross-sectional survey on lobectomy approach (X-SOLA).

BACKGROUND: Lobectomy for non-small cell lung cancer (NSCLC) can be performed either through open thoracotomy or video-assisted thoracoscopic surgery (VATS). To improve the understanding of current attitudes of the thoracic community toward VATS lobectomy, the Collaborative Research Group conducted the Cross-sectional Survey on Lobectomy Approach (X-SOLA) study. We surveyed a large cohort of lobectomy-performing thoracic surgeons to examine their adoption of VATS lobectomy and their opinions of this technique vs conventional open thoracotomy. METHODS: Participants included thoracic surgeons identified through an international index search from the Web of Science and the cardiothoracic surgery network. A confidential questionnaire was e-mailed in June 2012. Nonresponders were given two reminder e-mails at monthly intervals. RESULTS: The questionnaire, completed by 838 thoracic surgeons within a 3-month period, identified 416 surgeons who only performed lobectomy through open thoracotomy and 422 surgeons who performed VATS or robotic VATS. Of those who performed VATS, 95% agreed with the definition of "true" VATS lobectomy according to the Cancer and Leukemia Group B trial. Ninety-two percent of surgeons who did not perform VATS lobectomy responded that they were willing to learn this technique, but were hindered by limited resources, exposure, and mentoring. Both groups agreed there was a need for VATS lobectomy training in thoracic residency programs and in standardized workshops. CONCLUSIONS: X-SOLA represents the largest cross-sectional report within the thoracic community to date, demonstrating the penetration of VATS lobectomy for NSCLC internationally. From our study, we were able to identify a number of obstacles to broaden the adoption of this minimally invasive technique.

Innate immune responses after resection for lung cancer via video-assisted thoracoscopic surgery and thoracotomy.

OBJECTIVE: Innate immune responses to pulmonary resection may be critical in the pathogenesis of important postoperative pulmonary complications and potentially longer-term survival. We sought to compare innate immunity of patients undergoing major pulmonary resection for bronchogenic carcinoma via video-assisted thoracoscopic surgery (VATS) and thoracotomy. METHODS: Bronchoalveolar lavage was conducted in the contralateral lung before staging bronchoscopy and mediastinoscopy and immediately after lung resection. Blood and exhaled nitric oxide were sampled preoperatively and at 6, 24, and 48 hours postoperatively. RESULTS: Forty patients were included (26 VATS and 14 thoracotomy). There was a lower systemic cytokine response from lung resection undertaken by VATS compared with thoracotomy [interleukin 6 (IL-6), analysis of variance (ANOVA) P = 0.026; IL-8, ANOVA P = 0.018; and IL-10, ANOVA P = 0.047]. The VATS patients had higher perioperative serum albumin levels (ANOVA P = 0.001). Lower levels of IL-10 were produced by lipopolysaccharide-stimulated blood monocytes from the VATS patients compared with the thoracotomy patients at 6 hours postoperatively (geometric mean ratio, 1.16; 95% confidence interval, 1.08-1.33; P = 0.011). No statistically significant differences in the neutrophil phagocytic capacity, overall leukocyte count, or differential leukocyte count were found between the surgical groups (ANOVA P > 0.05). No statistically significant differences in bronchoalveolar lavage fluid parameters were found. Exhaled nitric oxide levels fell postoperatively, which reached statistical significance at 48 hours (geometric mean ratio, 1.2; 95% confidence interval, 1.02-1.46; P = 0.029). There were no significant differences found between the surgical groups (ANOVA P = 0.331). CONCLUSIONS: Overall, a trend toward greater proinflammatory and anti-inflammatory responses is seen with lung resection performed via thoracotomy compared with VATS.

Video-assisted thoracoscopic surgery lobectomy at 20 years: a consensus statement.

OBJECTIVE: Video-assisted thoracoscopic surgery (VATS) lobectomy has been gradually accepted as an alternative surgical approach to open thoracotomy for selected patients with non-small-cell lung cancer (NSCLC) over the past 20 years. The aim of this project was to standardize the perioperative management of VATS lobectomy patients through expert consensus and to provide insightful guidance to clinical practice. METHODS: A panel of 55 experts on VATS lobectomy was identified by the Scientific Secretariat and the International Scientific Committee of the '20th Anniversary of VATS Lobectomy Conference-The Consensus Meeting'. The Delphi methodology consisting of two rounds of voting was implemented to facilitate the development of consensus. Results from the second-round voting formed the basis of the current Consensus Statement. Consensus was defined a priori as more than 50% agreement among the panel of experts. Clinical practice was deemed 'recommended' if 50-74% of the experts reached agreement and 'highly recommended' if 75% or more of the experts reached agreement. RESULTS: Fifty VATS lobectomy experts (91%) from 16 countries completed both rounds of standardized questionnaires. No statistically significant differences in the responses between the two rounds of questioning were identified. Consensus was reached on 21 controversial points, outlining the current accepted definition of VATS lobectomy, its indications and contraindications, perioperative clinical management and recommendations for training and future research directions. CONCLUSION: The present Consensus Statement represents a collective agreement among 50 international experts to establish a standardized practice of VATS lobectomy for the thoracic surgical community after 20 years of clinical experience.

Serial characterisation of monocyte and neutrophil function after lung resection.

OBJECTIVES: The primary aim of this prospective study was to perform a comprehensive serial characterisation of monocyte and neutrophil function, circulating monocyte subsets, and bronchoalveolar lavage (BAL) fluid after lung resection. A secondary aim was to perform a pilot, hypothesis-generating evaluation of whether innate immune parameters were associated with postoperative pneumonia. METHODS: Forty patients undergoing lung resection were studied in detail. Blood monocytes and neutrophils were isolated preoperatively and at 6, 24 and 48 h postoperatively. BAL was performed preoperatively and immediately postoperatively. Monocyte subsets, monocyte responsiveness to lipopolysaccharide (LPS) and neutrophil phagocytic capacity were quantified at all time points. Differential cell count, protein and cytokine concentrations were measured in BAL. Pneumonia evaluation at 72 h was assessed using predefined criteria. RESULTS: After surgery, circulating subsets of classical and intermediate monocytes increased significantly. LPS-induced release of proinflammatory cytokines from monocytes increased significantly and by 48 h a more proinflammatory profile was found. Neutrophil phagocytosis demonstrated a small but significant fall. Factors associated with postoperative pneumonia were: increased release of specific proinflammatory and anti-inflammatory cytokines from monocytes; preoperative neutrophilia; and preoperative BAL cell count. CONCLUSIONS: We conclude that postoperative lung inflammation is associated with specific changes in the cellular innate immune response, a better understanding of which may improve patient selection and prediction of complications in the future.

Differential response to bacteria, and TOLLIP expression, in the human respiratory tract.

OBJECTIVES: The observation that pathogenic bacteria are commonly tolerated in the human nose, yet drive florid inflammation in the lung, is poorly understood, partly due to limited availability of primary human cells from each location. We compared responses to bacterial virulence factors in primary human nasal and alveolar cells, and characterised the distribution of Toll-interacting protein (TOLLIP; an inhibitor of Toll-like receptor (TLR) signalling) in the human respiratory tract. METHODS: Primary cells were isolated from nasal brushings and lung tissue taken from patients undergoing pulmonary resection. Cells were exposed to lipopolysaccharide, lipoteichoic acid, peptidoglycan, CpG-C DNA or tumour necrosis factor (TNF). Cytokines were measured in cell supernatants. TOLLIP was characterised using quantitative real-time PCR and immunofluorescence. RESULTS: In primary alveolar, but not primary nasal, cells peptidoglycan significantly increased secretion of interleukin (IL)-1ß, IL-6, IL-8, IL-10 and TNF. TLR2 expression was significantly higher in alveolar cells and correlated with IL-8 production. TOLLIP expression was significantly greater in nasal cells. CONCLUSION: In conclusion, primary human alveolar epithelial cells are significantly more responsive to peptidoglycan than primary nasal epithelial cells. This may partly be explained by differential TLR2 expression. TOLLIP is expressed widely in the human respiratory tract, and may contribute to the regulation of inflammatory responses.

Can thoracoscopic Heller's myotomy give equivalent results to the more usual laparoscopic Heller's myotomy in the treatment of achalasia?

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was 'Can thoracoscopic Heller's myotomy (THM) give equivalent results to the more usual laparoscopic Heller's myotomy (LHM) in the treatment of achalasia?' Altogether, more than 478 papers were found using the reported search, of which eight represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. THM and LHM are two recognised approaches to the performance of a distal oesophageal myotomy in the treatment of achalasia. Of the two meta-analyses on this subject, Campos et al. [Campos GM, Vittinghoff E, Rabl C, Takata M, Gadenstätter M, Lin F, Ciovica R. Endoscopic and surgical treatments for achalasia: a systematic review and meta-analysis. Ann Surg 2009;249:45-57] illustrated improved symptom control in LHM compared with THM. Wang et al. [Wang L, Li Y, Li L, Yu C. A systematic review and meta-analysis of the Chinese literature for the treatment of achalasia. World J Gastroenterol 2008;14:5900-5906], however, observed no difference in remission rates following either approach. Close scrutiny of comparison studies revealed superiority in long-term outcomes and symptoms following LHM in three studies. There were, however, studies that illustrated comparable outcome results for THM in both resolution of dysphagia and reflux. Morbidity rates following THM were noted to be similar to or slightly higher than those following LHM in five studies, but no statistically significant difference was illustrated in these studies. Operating time and length of stay were noted to be significantly shorter in LHM when compared with THM in three studies, although there were exceptions to this, with two studies illustrating shorter or equal operating times for THM. However, LHM operating times have been shown to improve with experience gained. We conclude that there is good evidence demonstrating the effectiveness and safety of LHM, and it has come to be regarded as the gold standard treatment of achalasia. When THM is compared with LHM, the long-term results approach parity on occasion but not consistently. The overall postoperative morbidity of THM is not significantly different from that of LHM. An advantage of LHM over THM that is demonstrated is that LHM offers a shorter hospital stay and reduced operative time.