The microfracture technique for the treatment of articular cartilage lesions in the knee. A prospective cohort study

BACKGROUND: Microfracture is a frequently used technique for the repair of articular cartilage lesions of the knee. Despite the popularity of the technique, prospective information about the clinical results after microfracture is still limited. The purpose of our study was to identify the factors that affect the clinical outcome from this cartilage repair technique. METHODS: Forty-eight symptomatic patients with isolated full-thickness articular cartilage defects of the femur in a stable knee were treated with the microfracture technique. Prospective evaluation of patient outcome was performed for a minimum follow-up of twenty-four months with a combination of validated outcome scores, subjective clinical rating, and cartilage-sensitive magnetic resonance imaging. RESULTS: At the time of the latest follow-up, knee function was rated good to excellent for thirty-two patients (67%), fair for twelve patients (25%), and poor for four (8%). Significant increases in the activities of daily living scores, International Knee Documentation Committee scores, and the physical component score of the Short Form-36 were demonstrated after microfracture (p < 0.05). A lower body-mass index correlated with higher scores for the activities of daily living and SF-36 physical component, with the worst results for patients with a body-mass index of >30 kg/m(2). Significant improvement in the activities of daily living score was more frequent with a preoperative duration of symptoms of less than twelve months (p < 0.05). Magnetic resonance imaging in twenty-four knees demonstrated good repair-tissue fill in the defect in thirteen patients (54%), moderate fill in seven (29%), and poor fill in four patients (17%). The fill grade correlated with the knee function scores. All knees with good fill demonstrated improved knee function, whereas poor fill grade was associated with limited improvement and decreasing functional scores after twenty-four months. CONCLUSIONS: Microfracture repair of articular cartilage lesions in the knee results in significant functional improvement at a minimum follow-up of two years. The best short-term results are observed with good fill grade, low body-mass index, and a short duration of preoperative symptoms. A high body-mass index adversely affects short-term outcome, and a poor fill grade is associated with limited short-term durability.     

Transgastric endoscopic peritoneoscopy does not require decontamination of the stomach in humans

Introduction  Natural orifice translumenal endoscopic surgery (NOTES) is a rapidly evolving field that provides endoscopic access to the peritoneum via a natural orifice. One important requirement of this technique is the need to minimize the risk of clinically significant peritoneal contamination. We report the bacterial load and contamination of the peritoneal cavity in ten patients who underwent diagnostic transgastric endoscopic peritoneoscopy. Methods  Patients participating in this trial were scheduled to undergo diagnostic laparoscopy for evaluation of presumed pancreatic cancer. Findings at diagnostic laparoscopy were compared with those of diagnostic transgastric endoscopic peritoneoscopy, using an orally placed gastroscope, blinding the endoscopist to the laparoscopic findings. We performed no gastric decontamination. Diagnostic findings, operative times, and clinical course were recorded. Gastroscope and peritoneal fluid aspirates were obtained prior to and after the gastrotomy. Each sample was sent for bacterial colony counts, culture, and identification of species. Results  Ten patients, with an average age of 63.7 years, have completed the protocol. All patients underwent diagnostic laparoscopy followed by successful transgastric access and diagnostic peritoneoscopy. The average time for laparoscopy was 7.2 min, compared with 18 min for transgastric instrumentation. Bacterial sampling was obtained in all ten patients. The average number of colony-forming units (CFU) in the gastroscope aspirate was 132.1 CFU/ml, peritoneal aspirates prior to creation of a gastrotomy showed 160.4 CFU/ml, and peritoneal sampling after gastrotomy had an average of 642.1 CFU/ml. There was no contamination of the peritoneal cavity with species isolated from the gastroscope aspirate. No infectious complications or leaks were noted at 30-day follow-up. Conclusions  There was no clinically significant contamination of the peritoneal cavity from the gastroscope after transgastric endoscopic instrumentation in humans. Transgastric instrumentation does contaminate the abdominal cavity but, the pathogens do not mount a clinically significant response in terms of either the species or the bacterial load.     

Liposarcoma of the head and neck: The University of Texas M. D. Anderson Cancer Center experience

Background.

Our aim was to review our experience with liposarcoma of the head and neck region.

Methods.

This is a retrospective case series at a comprehensive cancer center (1945–2005).

Results.

Of 30 patients, 10 (33%) were initially misdiagnosed. Local recurrences were common (overall rate = 53%), and 4 patients (13%) developed distant metastases. Decreased crude disease‐specific survival rates were significantly associated with recurrence (especially distant recurrence [0%]), age less than 38 years (40%), and pleomorphic subtype (45%); however, in Kaplan‐Meier analyses, only larger tumor size, negative margins, round cell subtype, and pleomorphic subtype were associated with significantly decreased disease‐specific survival (log‐rank test p = .048, .041, .021, and .012, respectively).

Conclusions.

Based on this limited experience and existing literature, we continue to recommend surgery with negative margins as the treatment of choice and that adjuvant therapies should be considered in patients with high‐grade histology, large tumors, positive margins, or certain subsites. © 2008 Wiley Periodicals, Inc. Head Neck, 2009     

Superior T-cell suppression by rapamycin and FK506 over rapamycin and cyclosporine A because of abrogated cytotoxic T-lymphocyte induction,impaired memory responses,and persistent apoptosis

Immunosuppressive therapy is best achieved with a combination of agents targeting multiple activation steps of T cells. In transplantation, cyclosporine A (CsA) or tacrolimus (FK506) are successfully combined with rapamycin (Rap). Rap and CsA were first considered for combination therapy because FK506 and Rap target the same intracellular protein and thus may act in an antagonistic way. However, in clinical studies, FK506+Rap proved to be effective. To date, there is no in vitro data supporting these in vivo findings, and it is unclear whether the observed effects are T-cell mediated. In a human polyclonal allogeneic in vitro model, we found that although combined drug treatment markedly reduced expansion of naive T cells, T-cell activation occurred irrespective of the drug combination used. The induction of cytotoxic effector T cells was reduced by CsA+Rap but completely abolished by FK506+Rap. Importantly, combined immunosuppression allowed generation of memory CD4+ and CD8+ T cells and hence did not result in T-cell anergy. However, FK506+Rap treatment resulted in a reduced number of allospecific memory T cells showing a decreased cell-cycle turnover and cytokine producing capacity. In contrast, CsA+Rap treatment led to increased memory T-cell numbers responding with elevated kinetics. The ability of Rap to promote apoptosis, which contributes to T-cell suppression, remained unaffected upon combination with FK506 or CsA. These data support the combined use of FK506+Rap over CsA+Rap for immunosuppressive therapy.     

Anatomy, pathology, and MRI findings in the sports hernia

"Sports hernia" is a frequently used term on athletic injury reports and in the sportscasting media, but its true definition remains elusive in the medical literature. Magnetic resonance imaging (MRI) is a useful tool in the evaluation of clinical athletic pubalgia, yet specific pathologies associated with this commonly encountered syndrome are poorly described in the imaging literature. In this article we review the musculoskeletal anatomy of the pubic region as well as several reproducible patterns of pathology on MRI we have encountered in patients with a clinical diagnosis of sports hernia.     

Collateral circulation imaging: MR perfusion territory arterial spin-labeling at 3T

BACKGROUND AND PURPOSE: Current knowledge of the collateral circulation remains sparse, and a noninvasive method to better characterize the role of collaterals is desirable. The aim of our study was to investigate the presence and distal flow of collaterals by using a new MR perfusion territory imaging, vessel-encoded arterial spin-labeling (VE-ASL).MATERIALS AND METHODS: Fifty-six patients with internal carotid artery (ICA) or middle cerebral artery (MCA) stenosis were identified by sonography. VE-ASL was performed to assess the presence and function of collateral flow. The perfusion information was combined with VE maps into high signal-intensity-to-noise-ratio 3-colored maps of the left carotid, right carotid, and posterior circulation territories. The presence of the anterior and posterior collateral flow was demonstrated by the color of the standard anterior cerebral artery/MCA flow territory. The distal function of collateral flow was categorized as adequate (cerebral blood flow [CBF] ≥10 mL/min/100 g) or deficient (CBF <10 mL/min/100 g). The results were compared with those of MR angiography (MRA) and intra-arterial digital subtraction angiography (DSA) in cross table, and κ coefficients were calculated to determine the agreement among different methods.RESULTS: The κ coefficients of the presence of anterior and posterior collaterals by using VE-ASL and MRA were 0.785 and 0.700, respectively. The κ coefficient of the function of collaterals by using VE-ASL and DSA was 0.726. Apart from collaterals through the circle of Willis, VE-ASL showed collateral flow via leptomeningeal anastomoses.CONCLUSIONS: In patients with ICA or MCA stenosis, VE-ASL could show the presence, the origin, and distal function of collateral flow noninvasively.

The protective effect of collateral circulation influences final clinical outcomes for patients with hemodynamically significant arterial stenosis. The principal source of collateral flow of cerebral arteries is through the arteries of the circle of Willis. Secondary collateral pathways include the external carotid artery via the ophthalmic artery and leptomeningeal anastomoses at the brain surface. However, the size and patency of these arteries are quite variable.Doppler sonography is the most common tool used to investigate the presence of collateral flows. MR angiography (MRA) can be used for determining the collaterals through the circle of Willis. However, both sonography and MRA do not show leptomeningeal collateral pathways, distal collateral flows, or the actual contribution of collateral flow to brain perfusion. Intra-arterial digital subtraction angiography (DSA) shows the presence and distal arteries of the collateral pathways.¹ However, to visualize all the collateral pathways, this technique requires an invasive and selective 3-vessel approach and is typically not performed in patients with acute stroke or cerebral arterial stenosis. Therefore, a noninvasive method that demonstrates selectively angiographic information may be desired to investigate collateral blood flow.²In MR perfusion territory arterial spin-labeling (ASL),^3–7 blood in individual or groups of feeding arteries is tagged by using ASL methodology, and images are acquired that map the vascular distribution of those feeding arteries. Recently, vessel-encoded ASL (VE-ASL) MR imaging⁸ was introduced as a more time-efficient method for mapping multiple vascular territories. The aim of our study was to investigate the presence and distal flow of collateral blood supply by using the VE-ASL technique at 3T on patients with carotid stenotic disease.     

High dose rate brachytherapy in the management of lung transplant airway stenosis

BACKGROUND: Airway complications after lung transplantation remain a major cause of postoperative morbidity and mortality. Interventional bronchoscopic management continues to be the main modality in the management of these problems. METHODS: Four patients with airway stenoses after lung transplantation received high dose rate brachytherapy for management of recurrent stenosis. All 4 patients had been treated with various bronchoscopic interventions, including dilation and stenting, electrocautery ablation, and neodymium:yttrium-aluminum-garnet laser therapy. High dose rate endobronchial brachytherapy was subsequently used in all 4 patients for management of recurrent airway obstruction. The radiation dose for all 4 patients was 3 Gy at a distance of 1 cm from the center of the catheter. RESULTS: All four patients have had routine follow-up after endobronchial brachytherapy treatments. Of the 4 patients, 2 treated with this modality showed a significant response to therapy in that the bronchus remained free of obstruction after treatment; 1 patient had partial improvement, and 1 patient failed to show significant improvement and expired from the sequelae of persistent airway obstruction. CONCLUSIONS: Endobronchial brachytherapy can be an effective modality for managing recurrent stenoses caused by hyperplastic granulation tissue at the bronchial anastomosis. The optimal timing and ideal candidate for intraluminal radiation therapy for this problem remains a challenge and warrants further investigation.     

Pharmacokinetics of Oxaliplatin During Open Versus Laparoscopically Assisted Heated Intraoperative Intraperitoneal Chemotherapy (HIPEC): An Experimental Study

Background

Hyperthermic intraperitoneal chemotherapy (HIPEC) is being evaluated for patients with minimal residual or no residual disease after primary surgery and chemotherapy for stage III ovarian carcinoma. The technical feasibility of the laparoscopic approach for HIPEC has been demonstrated in a previous study. An experimental study on the porcine model was carried out to compare oxaliplatin pharmacokinetics during a laparoscopic-assisted procedure versus the coliseum technique for HIPEC.

Methods

Adult pigs received an HIPEC procedure that was based on 460 mg/m² of oxaliplatin over 30 minutes with a perfusate heated at 41°C to 43°C. The HIPEC drains were placed in the upper and lower quadrants of the abdomen. Peritoneal fluid and blood samples were collected every 10 minutes during the procedure, and the pharmacokinetics of oxaliplatin was studied.

Results

Two groups of 10 adult pigs were studied. All the procedures were successfully completed with an adequate intra-abdominal temperature and distribution. No major technical problems were encountered. At the end of the HIPEC, 41.5% of the molecule was absorbed in the laparoscopic group compared with 33.4% in the laparotomy group (P = .0543). Peritoneal oxaliplatin half-life (T_½) was significantly faster in the laparoscopic procedure (median, 37.5 vs. 59.3 minutes, P = .02). The area under the curve ratio of peritoneal to plasma reflects a more important oxaliplatin crossing through the peritoneal barrier in the laparoscopic procedure (ratio, 16.4 in the closed procedure vs. 28.1 in the open one; P = .03).

Conclusions

This study confirms the technical feasibility and reliability of the laparoscopic approach for HIPEC, and it extends knowledge concerning peritoneal drug absorption. Oxaliplatin absorption is far higher with laparoscopy in terms of time course in peritoneal perfusion. Clinical application in selected patients may be expected after further experimental investigation designed to define the adequate drug dosage.

     

Modified Technique of Pancreaticojejunal Anastomosis with Invagination Following Pancreaticoduodenectomy: A Cohort Study

BACKGROUND: Leakage from pancreatic anastomoses remains the single most important morbidity after pancreaticoduodenectomy and contributes to prolonged hospitalization and mortality. This observational cohort study reported the surgical outcome of a modified invagination technique of pancreaticojejunostomy after pancreaticoduodenectomy. METHODS: Between December 2001 and December 2007, a total of 52 consecutive patients underwent elective pancreaticoduodenectomy for benign or malignant pathologies of the pancreas or the periampullary region in a tertiary referral center. All patients underwent our modified invagination technique of pancreaticojejunostomy regardless of the characteristics of the pancreatic stump. Data were collected prospectively. RESULTS: The mean hospital stay was 12.6 +/- 3.2 days. The incidence of overall surgical complications was 9.6%. No patient developed pancreatic fistula. One patient (1.9%) died of respiratory failure on postoperative day 7. CONCLUSIONS: We reported our pancreaticojejunostomy anastomosis technique with a pancreatic fistula rate of 0% and low intra-abdominal complication rate. The favorable results of this technique warrant further investigation in large prospective cohort studies and prospective randomized controlled studies.     

Older age at diagnosis of Hirschsprung disease decreases risk of postoperative enterocolitis, but resection of additional ganglionated bowel does not

Purpose

This study was conducted to determine the effect of age at diagnosis and length of ganglionated bowel resected on postoperative Hirschsprung-associated enterocolitis (HAEC).

Methods

Children who underwent endorectal pull-through (ERPT) between January 1993 and December 2004 were retrospectively reviewed. t Test, analysis of variance, Kaplan-Meier, and Cox's proportional hazards analyses were performed.

Results

Fifty-two children with Hirschsprung disease (median age, 25 days; range, 2 days-16 years) were included. Nineteen (37%) had admissions for HAEC. Proportional hazards regression showed that HAEC admissions decreased by 30% with each doubling of age at diagnosis (P = .03) and increased 9-fold when postoperative stricture was present (P < .01), after controlling for type of ERPT, trisomy 21, transition zone level, and preoperative enterocolitis. Thirty-six children, with age at initial operation less than 6 months, were grouped based on length of ganglionated bowel excised (A [5 cm] and B [>5 cm]). No significant difference in the number of HAEC admissions during initial 2 years post-ERPT was seen between groups A (n = 18) and B (n = 18). The study had a power of 0.8 to detect a difference of 1 admission over 2 years.

Conclusions

Children diagnosed with Hirschsprung disease at younger ages are at a greater risk for postoperative enterocolitis. Excising a longer margin of ganglionated bowel (>5 cm) does not seem to be beneficial in decreasing HAEC admissions.