The role of the le fort I maxillotomy in the management of incompletely resected pituitary macroadenomas.

Objective: The options available for the treatment of a nonsecreting pituitary macroadenoma that has been incompletely resected include reoperation, fractionated radiation therapy, and radiosurgery. Reoperation in this setting may be hindered by the same obstacles that prevented a complete resection during the initial surgical procedure, and should prompt consideration of an alternate approach or exposure. Methods: Between January 1998 and December 2003, 10 consecutive patients were referred to the Department of Neurosurgery at the University of Texas Southwestern Medical Center for the evaluation of a nonsecreting pituitary macroadenoma that measured 3 cm or greater in diameter despite having undergone an attempt at a complete resection elsewhere. Each of these patients was reoperated using a Le Fort I maxillotomy to enhance the exposure provided by a traditional transsphenoidal approach. Results: A total or near total (> 95%) resection was achieved in each case. One patient required reoperation for the repositioning of a fat graft to treat a cerebrospinal fluid fistula and one patient experienced a worsening of anterior pituitary function postoperatively. Five patients noted improved vision and no patient experienced further visual loss. Three patients have required subsequent treatment of small foci of recurrent or progressing tumor with stereotactic radiation therapy. No patient has received fractionated radiation therapy. Conclusion: The added exposure provided by a Le Fort I maxillotomy facilitates the resection of pituitary macroadenomas that have been incompletely resected by a traditional transnasal, trans-sphenoidal approach.     

Interobserver and interstudy variability of myocardial blood flow and flow-reserve measurements with nitrogen 13 ammonia-labeled positron emission tomography

Background  

Experimental studies have shown that positron emission tomography (PET) with ¹³N-labeled ammonia provides accurate quantification of regional myocardial blood flow (MBF) under rest and stress conditions. To establish the clinical utility of this method, the interobserver variability and the temporal variability of serial measurements of blood flow and coronary flow reserve (CFR) must be known. This study investigated the interobserver and temporal reproducibility of ¹³N-labeled PET for measurement of MBF and CFR.     

Advantages of the Papillon protocol in the preoperative treatment of rectal carcinoma.

Standard treatment for advanced rectal carcinoma currently includes surgery, radiotherapy, and chemotherapy. Although there are theoretic advantages to preoperative irradiation, it is often not performed because of the prolonged delay of surgery and the purported increase in perioperative complications. A pilot study was undertaken at our institution to evaluate a treatment protocol advocated by Dr. Papillon that offers a shorter treatment time and less patient morbidity than conventional preoperative therapy for rectal carcinoma. Twenty patients with rectal cancer underwent the preoperative regimen that consisted of 3,000 cGy delivered in 10 fractions over 12 days with concomitant 5-fluorouracil and mitomycin-C. Complications were acceptable. Local recurrence was lower than in most reported trials, and survival rates were comparable. Additional benefits of the protocol include lower radiation morbidity to the patient and a decreased delay between diagnosis and surgery.     

Detailed gene copy number and RNA expression analysis of the 17q12-23 region in primary breast cancers

Chromosome region 17q12-23 commonly shows an increase in DNA copy number in breast cancers, suggesting that several oncogenes are located at this site. We performed a high-resolution expression array and comparative genomic hybridization analysis of genes mapped to the entire 17q12-23 region, to identify novel candidate oncogenes. We identified 24 genes that showed significant overexpression in breast cancers with gain of 17q12-23, compared to cancers without gain. These genes included previously identified oncogenes, together with several novel candidate oncogenes. FISH analysis using specific gene probes hybridized to tissue arrays confirmed the underlying amplification of overexpressed genes. This high-resolution analysis of the 17q12-23 region indicates that several established and novel candidate oncogenes, including a Wnt-signaling pathway member, are amplified and overexpressed within individual primary breast cancer samples. We were also able to confirm the presence of two apparently separate and reciprocally amplified groups of genes within this region. Investigation of these genes and their functional interactions will facilitate our understanding of breast oncogenesis and optimal management of this disease.     

Juxtaposition of atrial appendages. Reinterpretation as an accessory appendage or atrial diverticulum

The pathological features of 13 cases with juxtaposition of the atrial appendages in the autopsy files of The Johns Hopkins Hospital were studied. The anomaly occurs most frequently in association with transposition of the great vessels, ventricular septal defect, patent foramen ovale, and obstructive lesions of the tricuspid and pulmonic valves. The malformation complex of tricuspid atresia, atrial and ventricular septal communication, and the transposition of the great vessels seems particularly common with juxtaposition of the atrial appendage. A recent case showed a small accessory right atrial appendage lying in juxtaposition to the left atrial appendage. In addition, a normally situated right atrial appendages in addition to well-formed accessory appendages lying in juxtaposition to the left atrial appendages. It seems that juxtaposition of the atrial appendages should be reinterpreted as an accessory appendage or atrial diverticulum.     

The influence of cardiac geometry on the results of ventricular aneurysm repair.

Operative repair of ventricular aneurysms should improve left ventricular function. Despite its theoretic advantage, the mortality following this operation is high, and many patients have severe postoperative hypotension. The cardiac findings were studied in 18 patients who died after repair of ventricular aneurysms. All hearts were examined at autopsy after postmortem coronary arteriography and fixation in a distended state. Five patients in Group I had intractable fatal postoperative hypotension, 7 in Group II initially had severe hypotension that improved, and 6 in Group III did not have postoperative hypotension. Curvature thickness indexes (CTIs) of the ventricular segments, which correlate with their pressure-producing activity, were determined in the 18 hearts. CTIs for the left ventricular free wall and septum were lower in Group I and Group II patients with hypotension than those in Group III without. The reduced CTIs in patients with postoperative shock appear to arise as a result of ventricular reconstruction that reduces ventricular wall curvature. The authors suggest that left ventricular function after aneurysm resection would be improved by inverting, rather than everting, the edges of the ventriculotomy, thereby increasing wall curvature and the CTI. Noninvasive determinations of the CTI may prove of value in guiding topographic reconstruction of ventricles with aneurysms.     

Continuum of the thickness of surviving myocardial wall with single myocardial infarcts

The pathologic correlate of the clinical terms subendocardial and transmural applied to myocardial infarcts is uncertain. To examine this question, we reviewed the morphology of 204 hearts with single myocardial infarcts studied at autopsy after coronary arteriography and fixation in distention. The thickness of surviving myocardium with the infarct (S) and the thickness of the adjacent noninfarcted myocardium (A) were measured microscopically and expressed as a ratio. The S:A ratios ranged from 0.00 to 0.83. Necrosis of the entire wall (S:A ratio = 0.00) was seen in 37 (18%) cases. Distribution of the remaining cases by 10% intervals of wall necrosis (ie, from 0.00 less than S:A ratio less than or equal to 0.10 through 0.90 less than S:A ratio less than or equal to 1.00) were present in 27, 33, 31, 24, 25, 12, 8, 6, 1, and 0 cases, respectively. A lower S:A ratio was correlated with infarct size, infarct expansion, infarct rupture, proximal location of the coronary artery lesion causing the infarct, recency of the infarct, and degree of endocardial mural thrombus. A higher S:A ratio was correlated with the degree of left ventricular hypertrophy. No correlation was observed between S:A ratio and several measures of coronary artery disease. Multivariate regression analysis showed that infarct expansion, infarct age, and rupture were distinct predictors of infarct thickness. The study shows that thickness of myocardium surviving with an infarct forms a continuum; there is no evidence of separate populations that would correspond to infarcts of transmural or subendocardial extent.     

The association of floppy mitral valve with disjunction of the mitral annulus fibrosus

Floppy mitral valve is usually attributed to connective-tissue degeneration. However, we have observed several instances in which both a floppy mitral valve and an abnormal mitral annulus fibrosus were present at autopsy. To study this association, we examined 900 hearts (after postmortem arteriography and fixation in distention) from autopsies of adults at The Johns Hopkins Hospital. Twenty-five (3 percent) of the hearts had a morphologically typical floppy mitral valve; in 23 of them (92 percent), the mitral annulus fibrosus showed disjunction--i.e., a separation between the atrial wall-mitral valve junction and the left ventricular attachment. In 42 other hearts (5 percent), which were from significantly younger patients (mean age [+/- SE], 60 +/- 2 years vs. 68 +/- 3; P less than 0.05), there was mitral annulus disjunction but no floppy mitral valve. Two hearts had a floppy mitral valve but no disjunction of the annulus; both of them had old infarcts of the papillary muscle. Our results show that floppy mitral valve is significantly associated with disjunction of the mitral annulus fibrosus (P less than 0.001). We suggest that floppy mitral valve develops from hypermobility of the valve apparatus, and that it is usually secondary to disjunction of the mitral annulus fibrosus, an anatomic variation in the morphology of the annulus.     

Role of the left interventricular sulcus in formation of the interventricular septum and crista supraventricularis in normal human cardiogenesis

Serial sections of normal human embryos were studied and three-dimensional images reconstructed to determine the early development of the interventricular septum. The position of the interventricular septum is determined in stage 9 of normal development by the formation of the left interventricular sulcus. As a result of unknown properties of the cells of the myocardial layer, the left interventricular sulcus persists while the right disappears, producing the initial lateral asymmetry of the primary heart tube. By stage 14, the left interventricular sulcus forms a spiral which is continuous with the developing interventricular septum. The dorsal limb of the spiral passes to the right between the atrioventricular canal and the origin of the outflow tract, and is lost in the wall of the trabeculated right ventricle. It appears that this dorsal limb of the spiral is the precursor of part of the cirsta supraventricularis. The midportion of the sulcus, the bulboventricular groove, becomes the socalled fibrous continuity between the aortic and mitral valves. The ventral limb of the spiral passes caudally in the anterior interventricular groove and then dorsally and cranially toward the dorsal cushion of the atrioventricular canal. The ventral limb of the spiral is continuous with the crest of the muscular interventricular septum, which develops by apposition of tissue from the expanding right and left ventricles. From stage 14 to stage 19, the muscular interventricular septum, the atrioventricular endocardial cushions, and the ventricular end of the spiral ridges of the outflow tract appose and fuse. Subsequent formation of the membranous interventricular septum completes the physical separation of the right and left ventricles.