Biomedical subjects

R D Nichols

Publications and source records attributed to R D Nichols.

At least 37 records · Page 2Linked to original sources

PubMed1989

Extracranial skull base chondrosarcoma.

Chondrosarcoma of the skull base is a rare neoplasm. The most common presenting symptoms are hoarseness, dysphagia, and diplopia, which is associated with palsies of cranial nerves X, IX, and VI. The temporal bone is the most common site of tumor origin, followed by the sphenoid bone. These tumors must be differentiated from chordoma, chondroid chordoma, osteogenic sarcoma, enchondroma, and meningioma. Diagnosis is made by patient history, radiologic imaging, and biopsy. The treatment is surgical excision followed by radiation therapy. Five-year survival rates for grades I, II, and III are 90, 81, and 43%, respectively.

Adult↗

PubMed1988

Comparison of survival in cardiac surgery at a Veterans Administration hospital and its affiliated university hospital.

Survival data were reviewed for 3330 open cardiac procedures from 1975 through 1984 at the William S. Middleton Memorial Veterans Hospital, Madison, Wis, and the University of Wisconsin Hospitals and Clinics, Madison. Respective operative survivals were 98.6% and 98.7% for myocardial revascularizations with vein graft or internal mammary artery (CABG), 96.2% and 96.8% for CABG reoperation, 97.8% and 95.9% for aortic valve replacement, 96.3% and 90.3% for aortic valve replacement plus CABG, 100.0% and 94.9% for mitral valve replacement, and 100.0% and 82.9% for mitral valve replacement plus CABG. There were no significant differences in six-year survival curves between hospitals despite threefold differences in average annual caseload (88 vs 294). This suggest that residency-directed cardiac surgery programs can function equally as well at a Veterans Administration hospital as at an affiliated university hospital.

Cardiac Surgical Procedures↗

PubMed1988

Concentration and distribution of thioridazine and metabolites in schizophrenic post-mortem brain tissue.

Thioridazine (THD) and its major metabolites, mesoridazine (MES), sulforidazine (SULF), and northioridazine (norTHD) accumulate at a predictable rate in human brain tissue after chronic medication. Although the concentration of THD is normally lower than or the same as its major metabolite, MES, in the plasma, it was found to be up to five times as concentrated in the brain tissue of treated patients. THD and its metabolites were evenly distributed throughout all regions of the brain in chronically medicated patients. Brain concentrations of THD were also compared with those of chlorpromazine (CPZ) when both drugs had been given at the same dose before death, and were shown to be up to 10 times more concentrated in brain at doses greater than 300 mg/day. Because some of the metabolites of THD are pharmacologically active, it is important to know how they accumulate in the brain in relation to the parent compound to understand how this drug mediates its clinical effect.

Aged↗

PubMed1987

Meningioma in the parotid region.

Meningiomas occurring ectopically in the neck are exceptional. We report two patients who presented as parotid and parapharyngeal masses and analyze them along with 27 previously reported cases. Typical patients present with parotid or parapharyngeal masses and cranial nerve palsies. Meningioma is not considered in differential diagnosis. The tumor is an extension of an unsuspected intracranial mass, occasionally with associated multiple meningiomas or other neurogenic tumors. Ectopic meningiomas should be considered in patients with parotid and parapharyngeal masses, particularly those with cranial nerve deficits; jugular foramen syndrome is most characteristic. Associated occult intracranial and temporal bone tumors and the cranial form of neurofibromatosis should be suspected. Treatment of cervical meningiomas is excision. The most important aspect of intracranial-extracranial lesions is recognition and treatment of the intracranial portion.

Adolescent↗

PubMed1986

Ectothermic philosophy of acid-base balance to prevent fibrillation during hypothermia.

In the ectotherms, or cold-blooded animals, carbon dioxide pressure decreases (PCO2) and pH increases as body temperature falls. This tends to increase coronary blood flow and prevent fibrillation. This concept was investigated in 181 consecutive patients undergoing open heart surgery of all types. In 121 cases, endothermic (warm-blooded) temperature-corrected normal values of pH, PCO2, and oxygen pressure were maintained during extracorporeal circulation as the perfusate temperature was lowered to 24 degrees C prior to aortic cross-clamping and administration of blood cardioplegia solution. In 49 patients (40%), ventricular fibrillation occurred prior to cross-clamping. In the other 60 consecutive cases, in which the ectothermic principle of cooling was applied, the PCO2 was allowed to decrease from 50 to 40 mm Hg and the non-temperature-corrected pH rose from 7.28 to 7.42. Fibrillation occurred in only 12 (20%) of these 60 patients.

Acid-Base Equilibrium↗

PubMed1986

Cranial invasion by basal cell carcinoma.

The direct spread of basal cell carcinoma (BCC) into the bones of the cranium takes a long period. In its early stages, it may not be detectable by radiography or computerized tomography, but can be visible as pitting during surgery. Invasion through the thickness of the calvarium due to extension of a BCC of the scalp, or involvement of the cribriform plate by spread from an intranasal lesion, is serious. Examples of cranial invasion by BCC are presented. The methods used in diagnosis and treatment are outlined.

Aged↗

PubMed1982

Lymphoma and the parotid gland.

The rich parotid lymphatic network makes necessary the inclusion of benign and malignant lymphoid disease in the differential diagnosis of parotid swelling. This area is affected directly by lymphoma in many clinical situations and has an indirect relationship with lymphoma through Sjögren's syndrome. These associations can produce uncertainty about the etiology and significance of parotid masses. Patients with Sjögren's have a spectrum of lymphoproliferative disorders from benign lymphoepithelial disease (BLD) to lymphoma and a significantly greater incidence of the latter than the general population. Nine patients with lymphoma and also benign and malignant lymphoid disease in the parotid illustrate various diagnostic considerations. These include that both benign and malignant parotid lymphoid pathology are seen with systemic lymphoma, that lymphoma can co-exist with BLD, may be misdiagnosed as BLD, and can develop in the same gland after appearance of BLD.

Adult↗

PubMed1980

Partial laryngectomy after radiation failure.

Of patients given radiation therapy as primary treatment for limited carcinoma of the larynx, 15-32% will not be cured by this modality. The recurrent tumor and primary site can be encompassed with a partial laryngectomy in a certain number of these individuals. This report reviews the subject of partial laryngectomy after radiation failure and reports experience with 18 patients who had partial laryngectomies to control recurrent or persistent carcinoma after full dose radiation therapy. Four patients had biopsy cures. Local tumor control was achieved by partial laryngectomy in 10 of 14 patients. Three of 4 partial failures were salvaged with total laryngectomy. Major wound complications were noted in 4 patients. Prolonged healing was observed in most patients. Prognosis is probably as good with partial laryngectomy as with total laryngectomy.

Adult↗

PubMed1980

Metastases to parotid nodes.

The differential diagnosis of masses in the preauricular and retromandibular regions includes a number of diseases in addition to primary tumors of the parotid. The lesions most commonly misdiagnosed as parotid tumors are intraparotid lymph nodes involved with inflammatory or neoplastic disease. Metastatic tumors in parotid nodes are unusual but must be considered. We present 12 patients with isolated metastases to parotid lymph nodes. Nine of the patients had primary tumors in the local afferent lymphatic bed. Three patients had metastases from unknown or distant sites. The majority of tumors that metastasize to the parotid are of cutaneous origin. Six of the patients had squamous cell carcinomas, three had adenocarcinomas, two melanomas and one a small cell carcinoma. The treatment of parotid metastases from local tumors is surgical removal of the parotid and associated regional nodes with postoperative irradiation therapy in certain instances. Management of the facial nerve should follow those principles appropriate for primary parotid tumors.

Adenocarcinoma↗

PubMed1979

Rhinocerebral mucormycosis.

Rhinocerebral phycomycosis is a serious and commonly fatal fungal infection. The causative organism, ordinarily a saprophyte, becomes pathogenic in persons who are made susceptible by coexisting, debilitating disease. We report a well-documented case of rhinocerebral phycomycosis where early diagnosis led to successful treatment, and we discuss important aspects of the clinical evaluation and management of such cases.

Brain Diseases↗

PubMed1979

Facial nerve function in 100 consecutive parotidectomies.

The risk of facial nerve paresis after parotidectomy is thought to be within acceptable limits, although it is difficult to find published data regarding the specific magnitude of this risk. This study reviews the subject and reports postoperative facial function in 100 consecutive patients who had parotidectomies at the Henry Ford Hospital during a 9-year period. Permanent weakness of a major branch was identified in 2 of 77 patients having lateral lobectomy for parotid disease. Both patients demonstrated marginal mandibular paresis after surgery for adenolymphoma. No weakness was noted in 16 patients undergoing total parotidectomy. No unanticipated nerve disability was noted in 4 patients having partial nerve sacrifice in extended procedures; 3 patients had complete sacrifice of the nerve.

Adenocarcinoma↗

PubMed1978

Bilateral acinous cell tumors of the parotid gland.

Acinous cell tumors are uncommon neoplasms which arise either from the secretory cells of the salivary gland acini or from pluripotential duct cells and occur almost exclusively in the parotid gland. Nine previous instances of the bilateral occurrence of this tumor in the parotid gland have been reported. We present a tenth case and illustrate several aspects of the clinical behavior of this unique tumor. The histological pattern of this type of tumor was considered universally to be benign until 1953 when attention was called to a malignant variant. It is difficult to find reference to a benign form after that time. It is, in fact, impossible to forecast the clinical behavior of an individual specimen based upon its histopathology. In order to recognize this unpredictability, the World Health Organization Classification of Epithelial Tumors of Salivary Gland Origin proposed a category, "Acinic Cell Tumors," separate from clearly benign or malignant neoplasms. Later, attention was called to the grammatical designation, "acinous cell tumor." Because acinous cell tumors are uncommon, numerically significant series are gathered from several institutions or over several decades during which treatment methods vary widely. This makes it difficult to accept the validity of conclusions based upon the reported data. There is, however, a clearly documented tendency of the tumor to recur after long symptomless intervals so that extended follow-up is necessary before "cure" is established. Treatment of acinous cell tumors is surgical. The value of radiation therapy in the management of recurrent tumors is not firmly established.

Carcinoma↗

PubMed1977