Pharyngeal lymphatic ring: anatomical review

The tonsils form part of a circular band of adenoid tissue which guards the opening into the digestive andrespiratory tubes, known as Waldeyer’s ring. The anterior part of the ring is formed by the submucouslymphoid clusters (lingual tonsil) on the posterior part of the tongue; the lateral portions consist of thepalatine tonsils and the lymphoid tissue in the vicinity of the auditory tubes, while the ring is completedbehind by the pharyngeal tonsil on the posterior wall of the pharynx. In the intervals between these mainsmaller collections of lymphoid tissue are found. This paper intends to give to the clinician an anatomicalreview about the subject.

Transabdominal or totally extraperitoneal laparoscopic hernia repair?

Laparoscopic repair of inguinal hernias follows some principles that have already proven its efficiency, as a posterior approach and the prosthetic repair that allows a "tension-free" repair with consequent early return to work and low recurrence rate. To determine the most appropriate laparoscopic repair, we compared the transabdominal preperitoneal (TAPP) and the totally extraperitoneal (TEP) approach. Patients undergoing TAPP and TEP were compared regarding technical feasibility and difficulties, time until return to work and follow-up, including intraoperative and postoperative complications. Seventy-eight patients (108 hernias) were submitted to TAPP and 67 (100 hernias) were repaired through TEP. All data were analyzed by Yates-corrected chi-square test to qualitative analysis of each group and p < or = 0.05 was considered significant. Both procedures were indicated mainly for bilateral and/or recurrent hernias (68%). The operative time was shorter in TAPP (not statistically significant). Surgeons complained of more technical difficulties while performing the TEP approach (70% complaints of difficulty in TEP--four conversions to TAPP). There was no difference in hospital stay (mean of 30 h) and return to work (TAPP 7 days and TEP 5.5 days). Regarding the complication rate (TAPP = 20.5% and TEP = 13.5%; not significant), none were related to the pneumoperitoneum technique or its systemic effects. In the TAPP approach, two trocar site hernias occurred, and in the TEP approach, one severe cellulitis occurred, which was managed without surgical intervention. The mean follow-up period for each procedure was not the same, so the recurrence rates are not comparable statistically (rate of 1.85% in TAPP and 0 in TEP). Both techniques are safe and have the same advantages, but TAPP is easier: a better view of the anatomy is achieved, shortening the learning curve. We suggest that TAPP can be an adequate laparoscopic approach to groin hernias. A longer follow-up period and more cases are needed to determine recurrence rates.

Laparoscopic extraperitoneal repair of inguinal hernias.

The world of surgical laparoscopy is evolving. Laparoscopic prosthetic inguinal hernia repair is gaining rapid and wide acceptance. This experience consisted of 144 hernia repairs in 105 patients (40 bilateral, 31 recurrent, and 33 unilateral nonrecurrent hernias), treated through an extraperitoneal laparoscopic repair. When compared with transabdominal repair, operative time and postoperative recovery were similar, with some advantages related to the avoidance of intraabdominal manipulation and potential related complications. In spite of a relatively short follow-up (up to 40 months), there were no recurrences in this series. Morbidity rate was acceptable (16.1%), mainly reported as minor complications. Anatomical and technical skills to perform the operation are required and achieved through training. Extraperitoneal hernia repair with synthetic mesh is safe and feasible, with the advantages of being associated with less pain, rapid return to full activities, and the already proven milder systemic responses following interventional laparoscopy.

Experimental injury to the spleen study of interaction: contamination/preservation.

Ablation of the spleen leads to a significant risk of postsplenectomy invasive sepsis. This concept has become very important in the last three decades because of awareness of the spleen's important role in immunological functions. Hence, this has led many research centers to study hemostasis of the injured spleen in order to preserve its function. The objective of this study is to analyze the use of nylon mesh for preservation of the wounded spleen in the presence or absence of local contamination. Twenty dogs were operated, randomly divided into two groups and followed postoperatively for eight weeks. A standard splenic injury was produced in all animals and hemostasis accomplished by attaching nylon mesh to the organ. Postoperatively, in one of the groups the "wounded organ + mesh" was contaminated with a bacterial count proportional to the animal's weight. The other group was not contaminated, maintaining it as control. Both groups were studied as to interaction of contamination/preservation, i.e., body weight, surgical findings, splenic size and histology, blood and tissue culture and hematological data. The dogs adequately withstood the standardized trauma regardless of local contamination. And the nylon mesh effectively arrested bleeding in all animals. At sacrifice inoculated germs were confirmed in the contaminated group by histological methods or tissue cultures. A cellular infiltrate of lymphocytes and plasmocytes was present close to the mesh only in the latter. The mesh attached to the injured spleen did not lead to abscesses, intrasplenic or intraperitoneal fluid collections. Based on analysis of the data, we can infer that local contamination of the injured spleen and the presence of non-absorbable material (nylon mesh) did not markedly alter the overall behavior of the dogs compared to the uncontaminated group.

[Penetrating trauma of the neck: prospective study of 53 cases]. / Ferimentos penetrantes cervicais: análise prospectiva de 53 casos.

The treatment of penetrating injuries of the neck is still controversial nowadays, especially when there is doubt concerning the existence of any anatomic structure lesion. The delay to indicate surgical cervical exploration may predispose the patient to have serious sequels when the esophagus or the trachea are injured. The infection which may occur in this eventuality progresses rapidly to the mediastinum, determining the patient's death. The purpose of this work was to identify and to analyze the parameters which suggest the best treatment indicated for patients with penetrating injuries of the neck. This is a non-randomized prospective study which gathered 53 patients, victims of penetrating wounds of the neck, treated at the Emergency Surgical Service of the Hospital das Clínicas, University of São Paulo School of Medicine, during a three-year period, starting in October, 1990. All the patients were evaluated by the surgical team on call who elected the selective exploration approach for the cases that did not present clear evidence of injuries in the cervical structures nor hemodynamic alterations. For the fifteen carriers of evident injuries, immediate surgical exploration was the treatment adopted. All the patients had epidemiologic data, evaluation results, hospitalization period, complications, morbidity and mortality rates, besides trauma indexes, collected. For patients whose clinical observation was allowed, endoscopic studies were also performed and compared. In order to evaluate variable correlations, statistical analysis were performed using Q square test, Student test and Z statistics, which leaded to the following conclusions: 1. Penetrating wounds of the neck were most frequent in white people aged from 20 to 30 years. They were mostly located in the right side of cervical zone II and were caused by gunshot. 2. Trauma indexes correlated with patients' clinical evolution. 3. In cases when there was doubt about the effective presence of injuries, complementary digestive and respiratory evaluations were indicated. These exams contributed for reducing the rate of unnecessary surgical explorations.

An experimental study of the impact of cancer on nitrogen metabolism and wound healing.

In Wistar rats bearing a Walker-256 carcinoma flank tumor, a standard skin wound was inflicted on the backs of the animals. Nitrogen intake and nitrogen balance measures were obtained. The standard wound did not promote tumor growth. Wound contraction in tumor-bearing animals was not different from that in tumor-free animals. Tumor-bearing rats had anorexia, lower nitrogen intake and a tendency to lower their nitrogen balance. These findings suggest that both cancer and wound healing are privileged metabolic events, having as a consequence sacrifice of the host.

Effects of protein depletion and repletion on experimental open wound contraction.

A controlled comparative study was conducted on the contraction of open wounds in protein-depleted and depleted-repleted Wistar rats. The wounds were photographed on days 1, 4, 8, 11, 15, 18, and 22 after infliction. The slides were projected and the areas corresponding to the wound were measured by planimetry. The results were analyzed using exponential regressions. Wound contraction was slowed in the protein-depleted animals but was normalized in the animals repleted immediately after the wound was produced. Comparing these results with observations from previous studies, the authors inferred that deficiencies in wound contraction in depleted animals are caused by morphological and functional changes in the granulation tissue. These deficiencies are promptly corrected by protein repletion.

The effects of protein malnutrition on wound contraction: an experimental study.

The effects of protein malnutrition on wound contraction experimentally produced in Wistar rats were studied. The wounds were photographed on the first, fourth, eighth, eleventh, fifteenth, eighteenth, and twenty-second days. From dressings made from the projection of transparencies the contracted wounds were measured with a planimeter. Open wounds contracted more slowly in the malnourished group. Matching these observations with histopathological findings based on serial observations in these same animals, the differences between the contraction of open wounds in poorly nourished animals and in the control group seem to be associated with delay in the formation and the poor quality of granulation tissue in the malnourished.

[Levels of hepatic fats in jejuno-ileal bypass. Experimental study]. / Níveis de gordura hepática nas derivações jejuno-ileais. Estudo experimental.

Liver failure is a serious complication when small bowel bypass is used for control of obesity. To analyse the changes in liver microscopic morphology and liver fatty acids content, 42 rabbits divided in two groups were studied. The 21 animals of group I had 50% of the distal jejuno-ileum excluded and anastomosed to the cecum. The proximal 50% were anastomosed to the distal 5 cm of the ileum. The 21 animals of group II were used as controls and were submitted to a laparotomy and small bowel manipulation. Liver histology and fatty acids content were studied at the time of these operations and in the 21st postoperative day. No signficant histologic changes were noticed in both groups. A significant decrease in liver fatty acids content was observed in groups I and II. However, the decrease in group II was less pronounced than in group I. This last observation appears to support the theory of liver lipid metabolism impairment after small bowel bypass, even in the absence of obesity.