How securely is the testicular artery occluded in the spermatic cord by using a ligature?

REASONS FOR PERFORMING STUDY: There are no studies on the ideal ligature technique for the spermatic cord. OBJECTIVES: To compare the maximal resistance pressure in the testicular artery and the maximal tensile forces to produce failure of 2 different ligature techniques used for ligation of the equine spermatic cord. METHODS: The capabilities of 2 types of ligatures, single knot loop and double knot loop, were assessed using a pressure-resistance test in testicular arteries and with an in vitro mechanical evaluation of the tensile strength by single cycle-to-failure testing. RESULTS: In the pressure-resistance test, the mean ± s.d. peak force at failure of the single knot loop was 354.4 ± 91.7 mmHg and for the double knot loop 303.2 ± 62.0 mmHg. There was no significant difference between the maximal load to failure of the single knot loop and double knot loop technique. The pressure needed for rupture was significantly higher (P = 0.001) than for leakage. The maximal tensile force at failure of the single knot loop was significantly higher than the double knot loop (P = 0.028). There was no significant difference in load elongation properties to failure between the single knot loop and double knot loop. CONCLUSIONS: Although no significant differences were obtained in the pressure-resistance test, the single knot loop sustained significantly greater load to failure than the double knot loop in single cycle-to-failure testing. Based on these findings, it would appear that the performance of the single knot loop should be superior to the double knot loop. POTENTIAL RELEVANCE: Both ligature techniques are able to withstand the normal physiological intravascular pressure. The single knot loop has the greater breaking strength of the 2 ligatures tested and is less time consuming to perform and may therefore have advantages during equine castration.

Penetration of the skull base by dissecting keratocyst.

The extensive destructive potential of the keratocyst has been well recognized but penetration of the keratocyst into the skull base is rare. 3 cases showing such aggressive behavior and rare location were seen and treated; 2 are reported in this paper. Both cases illustrate the importance of early radical treatment once the aggressive nature of keratocyst is recognized.

Loss of factor XIIIa in pig dermis during tissue expansion.

Considerable evidence suggests that factor XIIIa, a blood coagulation factor, also functions in tissue repair, and specifically in the dynamic process of fibroplasia. On the other hand, the dynamic process of tissue expansion would require a loosening of the dermis, the opposite of fibroplasia. We examined the effects of tissue expansion on the expression of factor XIIIa in pig skin. Standard immunohistochemical procedures were used coupled with a rabbit antibody to factor XIIIa. In this report, we demonstrate that the normal expression of factor XIIIa in pig dermis is completely inhibited at the apex overlying the tissue expander. Factor XIIIa inhibition during expansion supports the thesis that this substance is important in the production and maintenance of fibroplasia.

Recurrent squamous-cell carcinoma arising in pilonidal sinus tract--multiple flap reconstructions. Report of a case.

Squamous-cell carcinoma arising from a pilonidal sinus tract is an unusual complication of a common condition. Approximately 36 cases of carcinoma related to pilonidal disease have been reported in the literature. Wide excision with tumor-free margins has yielded five-year disease-free states in 55 percent of patients. Recurrence rates have been 44 percent to 50 percent in several large series. Regional (inguinal) nodal metastasis occurs in 14 percent of patients, heralding a dismal prognosis. Radiation and chemotherapy are of minimal palliative value. Reconstruction of these patients has consisted of split-thickness skin grafts or local cutaneous and myocutaneous flaps. Some authors have allowed healing by secondary intention. A case of squamous-cell carcinoma arising in a chronic pilonidal sinus tract is reported. Local recurrence required an extensive resection resulting in a large sacral/perineal defect. A single-stage reconstruction of this defect with multiple muscle and musculocutaneous flaps is described.

Desmoid tumors of the head and neck.

Desmoid tumors of the head and neck are uncommon and associated with a posttreatment recurrence rate as high as 70 percent. This study was undertaken to determine cure rates achievable by surgery and radiotherapy and the factors influencing failure. A chart review of all patients at our institution with desmoid tumors of the head and neck from 1919 to 1982 was undertaken, and pertinent data were tabulated. Forty-eight patients were found with this problem. Average duration of symptoms was 1.6 years, and tumor size ranged from 1 to 12 cm (mean 5.1 cm). Average follow-up was 5.8 years. The most common site of occurrence was the neck (34 patients). Thirty-two patients underwent complete excision with 8 recurrences; 4 were reexcised with no further recurrence at last follow-up. Fourteen patients had incomplete excision with 12 recurrences. Radiotherapy was employed as the primary therapy in two patients; both experienced recurrence. Complete excision is the only effective treatment for desmoid tumors of the head and neck, resulting in a disease-free state in 75 percent of the patients (87 percent after reexcision). Involvement of the brachial plexus was the chief factor precluding complete excision. Radiotherapy was of very little value.

Monitoring muscle viability using evoked M waves.

The experiments described reveal the direct relationship between blood flow and evoked electrical activity in muscle flaps. It is demonstrated that monitoring of EMWs will detect vascular occlusion to a muscle flap within 1 hour. Detecting failure this soon provides the surgeon an opportunity for reexploration and salvage of a muscle flap before irreversible change has occurred. Correlations with observed muscle contraction and intramuscular temperature changes are also made.

Combined disturbance of respiratory regulation and esophageal function in early infancy.

An evident coincidence exists between increased and extended apneas during sleep and frequent gastroesophageal reflux as well as disturbances of propulsive esophageal peristalsis. The tendency to develop apnea and disturbed esophageal function are related to the degree of the maturity of the patient. This indicates that in some infants, a combined regulatory immaturity of the autonomic centers persists. Moreover, the gastroesophageal reflux fosters the clinical manifestation of sleep apneas. The risk of a reflex apnea accompanied by gastroesophageal reflux increases in proportion to the disturbance in the central respiratory regulation present at the same time. This pathomechanism can be considered one of the causes of the sudden infant death syndrome. The possibility of effective prophylaxis consists in treating the apneic tendency with aminophylline and the treatment of reflux by elevating the upper body and thickening the nourishment given.