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S Ramasastry

Publications and source records attributed to S Ramasastry.

13 recordsLinked to original sources
PubMed1998

A new rat model to study the correlation of cardiac and skeletal muscle allograft rejection.

As a first step to study the correlation of cardiac and skeletal muscle allograft rejection, we describe a new experimental rat model of simultaneous heterotopic heart and cutaneous maximus muscle flap allotransplant. Brown Norway rats were used as donors and Lewis rats as recipients. No immunosuppression was given. The grafts were revascularized with sequential end-to-side anastomosis of each vascular pedicle to the infrarenal aorta and vena cava. Syngeneic heart and cutaneous maximus muscle grafts remained functional and showed no sign of rejection at 7 days after the transplant. In contrast, both allografts developed severe rejection and functional compromise at 7 days after the transplant. Our experimental model is technically feasible and reproducible and may provide important information about the pattern of rejection of cardiac and skeletal muscle allografts.

Animals↗
PubMed1996

Coumadin necrosis of the skin: report of four patients.

Necrosis of skin and soft tissue as a complication of oral anticoagulation therapy is a rare condition with approximately 200 cases documented in the world. Coumadin-induced skin necrosis is a painful skin lesion, sudden, localized, initially erythematous or hemorrhagic, that becomes bullous and eventually culminates in gangrenous necrosis. It develops mainly in women around 50 years of age who are usually obese and have been treated for thrombophlebitis or pulmonary embolism. There seems to be a marked predilection for areas with increased subcutaneous fat content, such as breasts, thighs, and buttocks. The injury is so significant that plastic surgery is frequently required to repair the damaged tissue. The authors present four clinical cases of Coumadin necrosis, observed in two different institutions, and perform a literature review on the mechanisms that trigger the development of the disease. This condition still remains a diagnostic-therapeutic challenge.

Adult↗
PubMed1996

Simultaneous distraction osteogenesis and microsurgical reconstruction for facial asymmetry.

Restoring facial balance in patients with severe facial asymmetry is a challenging problem for the craniofacial team. Attention to bony reconstruction as well as soft-tissue contouring is required for patients with moderate to severe deformities. Traditionally, facial skeletal reconstruction was performed with osteotomies and bone grafting. More recently, distraction osteogenesis has proven to be successful in achieving bone lengthening. For select cases, distraction osteogenesis has lessened the need for major skeletal procedures and has allowed earlier surgical intervention. The reconstruction of the soft tissues in facial asymmetry has generally been performed as a second-stage procedure after skeletal reconstruction. The disadvantage of these traditional approaches is that it requires two separate major operative procedures, with the accompanying increased morbidity, hospital stay, and cost. We present a patient with hemifacial microsomia and a grade III mandibular deformity, in whom both the hard- and soft-tissue deficiencies were corrected in one surgical procedure with mandibular distraction osteogenesis and soft-tissue augmentation with a vascularized parascapular osteocutaneous flap. The technique and results at 1-year follow-up are presented.

Adolescent↗
PubMed1994

Cranial base surgery: results in 183 patients.

OBJECTIVE: To learn about the effects of cranial base surgery. DESIGN: Cohort study with a mean follow-up of 30 months. SETTING: Population-based. PATIENTS: A consecutive sample of 183 patients who underwent cranial base surgery; 118 patients had malignant skull base tumors, the majority of which were previously treated; 50 had benign tumors; 9 had congenital malformations of the skull base; 3 had inflammatory lesions, and 3 had traumatic defects of the skull base. MAIN OUTCOME MEASURES: Disease-free interval, overall survival, and rate of complications and functional status. INTERVENTION: Cranial base surgery was followed by radiotherapy (in previously untreated patients). RESULTS: After completion of follow-up (mean, 30 months), 30 (25.4%) patients had died of their malignant tumors and 8 (6.8%) had died of other causes. One patient (0.84%) was lost to follow-up. The overall cancer survival rate without regard to histologic type was 67% (63% with no evidence of disease). Among the patients who were treated for benign neoplasm, 72% had no evidence of disease at a mean follow-up of 39 months. The group of patients with congenital malformations and inflammatory and traumatic lesions demonstrated successful correction of their presurgical problem with skull base surgery. One patient (who had invasive aspergillosis) died of disease. The overall surgical-medical mortality rate was 2%; the complication rate was 33%, and the Karnofsky performance score was improved or unchanged after surgery in 83% of patients. The average duration of surgery, number of blood transfusions used, and length of the hospital stay were 10 hours, 3 units, and 15 days, respectively. CONCLUSIONS: Cranial base surgery is a valid surgical technique for treatment of cranial base afflictions. In this study it was found to be beneficial in controlling benign and malignant disease and to be the treatment of choice for selected congenital malformations, trauma, and inflammatory lesions.

Adolescent↗
PubMed1993

Reconstruction of radiation-induced chest wall lesions.

Radiation-related ulcers of the chest wall provide a great challenge to reconstructive surgeons because of the necessity of protecting the underlying vital structures and the difficulty in repairing irradiated tissues. To evaluate the efficacy of treatment, 24 patients who underwent reconstruction of radiation related ulcers of the chest wall were retrospectively reviewed. A variety of muscle and musculocutaneous flaps as well as omentum and microvascular tissue transfers were used to reconstruct these defects. The defects in the chest wall arose from spontaneous breakdown of irradiated tissue, tumor recurrence, or nonhealing after surgical procedures performed in the irradiated field. Our treatment protocol consisted of aggressive debridement of all affected tissues including skeletal tissues when necessary. The application of a tension free closure using a flap was then performed. Skeletal support was provided in three reconstructions. There were no mortalities, the morbidity rate was 29% (six minor, one major complication), and the mean hospital stay was 10.9 days. None of the patients required prolonged ventilator support. In all but 2 patients, who were left with small chronic granulating nonhealing wounds, complete wound healing was achieved. We conclude that chest wall reconstruction of radiation-related ulcers can be achieved with minimal morbidity in an acceptable period of inpatient hospital care using a variety of vascularized tissue transfers.

Aged↗
PubMed1993

Combined tissue expansion and free tissue transfer for reconstruction of the hand in epidermolysis bullosa-associated malignancy.

The recessive form of dystrophic epidermolysis bullosa (RDEB) is associated with severe hand deformities characterized by cocooning pseudopolysyndactyly, recurrent ulceration, fibrosis, and adduction contracture of the thumb. In addition, RDEB is associated with an aggressive form of squamous carcinoma, notable for rapid metastases, appearance at an early age, and a relative resistance to radiation or chemotherapy. To date, reported reconstructive treatment has been limited to excision with skin grafting or amputation. We report the successful combined use of tissue expansion and microsurgical free tissue transplantation to reconstruct a patient with RDEB found to have malignancy of the hand. Donor skin was found to expand without blistering, and use of the expander allowed primary donor site closure after microsurgical transplantation of a scapular flap. We recommend wide tumor resection and the aggressive use of contemporary reconstructive methods to maintain hand function and associated quality of life in patients with RDEB who develop malignancy.

Adult↗
PubMed1992

Hyperbaric oxygen therapy: effect on middle ear and eustachian tube function.

Hyperbaric oxygen therapy (HBO) involves intermittent inhalation of 100% oxygen under a pressure greater than 1 atm. It is an important mode of adjuvant therapy for disease processes such as decompression sickness, osteomyelitis, carbon monoxide poisoning, and poorly healing wounds. Patients undergoing this therapy often complain of ear pain and/or fullness which can be transient or long standing. This prospective study objectively measured the changes in eustachian tube function before and after HBO treatment in 33 adult patients by the 9-step inflation-deflation test described by Bluestone. The results show 15 of the 33 patients (45%) had evidence of eustachian tube dysfunction after treatment was initiated. Of these, 15 (100%) developed the sensation of fullness, 13 (87%) developed serous otitis media, and 7 (47%) required tympanostomy tubes. The overall incidence of middle ear problems was 27 patients (82%) experiencing a sensation of fullness, 17 (52%) developing serous otitis media, and 8 (24%) requiring tympanostomy tubes. The middle ear complications reported in this study are much higher than those in previous reports in the literature. Twelve of 33 patients presented with a subjective history of eustachian tube dysfunction, and all 12 (100%) developed fullness in their ears and serous otitis media during the course of the treatment. The findings reveal that patients manifesting eustachian tube dysfunction after their first HBO treatment were at significantly greater risk toward developing symptoms of fullness and serous otitis media, often requiring tympanostomy tube placement. In addition, a history of eustachian tube dysfunction accurately predicted the development of fullness and serous otitis media.

Acoustic Impedance Tests↗
PubMed1992

Temporal bone neoplasms: a report on 20 surgically treated cases.

The surgical resection of neoplasms involving the petrous bone and surrounding areas in 20 patients is reported. Technical advances described include the total resection of several tumors previously considered inoperable due to involvement of dura and brain, petrous internal carotid artery (ICA), the vein of Labbé, and adjacent areas such as the clivus and the cavernous sinus. Areas of reconstruction after resection included the ICA, the seventh and 11th cranial nerves, and the cranial base, often requiring the use of vascularized flaps. There were no intraoperative deaths. Many patients experienced significant temporary morbidity related primarily to wound healing and to lower cranial nerve palsy; however, all but three patients (all with fast-growing malignancies) returned to their preoperative functional status. During a median follow-up period of 30 months (range 17 to 63 months), the 10 patients with benign tumors and slow-growing malignancies fared well, seven being alive and disease-free. The 10 patients with fast-growing malignancies fared poorly, only two being alive without disease. This outcome appeared to be related to tumor pathology and extent of invasion; both survivors harbored tumors confined to the petrous bone. An anatomical classification system of tumor spread is introduced, which should be considered concomitantly with tumor pathology.

Adolescent↗
PubMed1987

Severe amniotic band syndrome occurring with unrelated syndactyly.

A patient with severe amniotic band syndrome and true proximal syndactyly of the hand and foot is presented. The occurrence of these two seemingly unrelated anomalies may be pathologically linked with amniotic band syndrome in some as yet unexplained way or less likely may occur with amniotic band syndrome coincidentally.

Abnormalities, Multiple↗
PubMed1986

Devastating scalp infections.

The treatment of scalp wounds is occasionally complicated by infection. Although infected scalp wounds are generally limited and readily treated, they can progress to devastating proportions if not promptly and aggressively managed. This report highlights three such cases of severe infection: extensive subgaleal abscess, fatal necrotizing fasciitis, and widespread carbunculosis. The authors emphasize the need for proper assessment of scalp wounds, meticulous cleansing and closure of all fresh wounds, definitive drainage of newly infected wounds, and adherence to sound surgical principles in managing these wounds.

Abscess↗