Parakrama Chandrasoma

Computed imaging stereotaxy: experience and perspective related to 500 procedures applied to brain masses

The evolution of more sophisticated imaging techniques has initiated a renewed interest in stereotactic devices, methods, and applications. The Brown-Roberts-Wells instrument was available to us early in its prototype stage, and this report reviews the first 500 cases using the system at the University of Southern California Medical Center Hospitals. Procedures were undertaken after recognition of apparent structural alterations on imaging studies, with objectives being both diagnostic and therapeutic. Target locations were predominantly within the cerebral centrum-basal ganglia (284 cases) and diencephalic-mesencephalic regions (129 cases). Operative objectives included: histological and microbiological assay, cyst and abscess aspiration, installation of temporary or permanent drainage conduits, point source and colloid base brachytherapy, cerebroscopy and ventriculoscopy with biopsy, aspiration, and excision, and intraoperative vascular localization. Using multiple instrumentation at the target point (741 point placements), we realized procedural objectives in 95.6% of the cases. The mortality was 0.2% and the morbidity was 1%: hematoma, 2 cases; infection, 1 case; increased deficit, 1 case; intraprocedural seizure, 1 case. A specific diagnosis was not obtained in 4.4% (necrosis, 10 cases; inflammatory response, 9 cases; granuloma, 1 case; gliosis, 1 case; diagnostic error, 1 case). Individual guidelines for case selection, technique, institutional requirements, and applications of the method are discussed.(ABSTRACT TRUNCATED AT 250 WORDS)

Histology of the gastroesophageal junction: an autopsy study.

Current diagnostic criteria for reflux disease and Barretts esophagus are based on the belief that the gastroesophageal junction normally contains 2 cm of cardiac mucosa composed of mucous glands devoid of parietal cells. This autopsy study disproves this belief. Even when the entire circumference of the gastroesophageal junction is examined, pure cardiac mucosa was completely absent in 56% of patients. All patients had oxyntocardiac mucosa, in which glands contained a mixture of mucous and parietal cells. Cardiac and oxyntocardiac mucosae were present only in part of the circumference of the junction in 50% of patients. The measured maximum length of cardiac plus oxyntocardiac mucosa was less than 0.5 cm in 76% of patients. There was a tendency for the presence and extent of cardiac mucosa to increase with age. Cardiac mucosa at the junction is therefore frequently absent, has considerable individual variation, is very small in extent when present, is commonly absent from some part of the circumference of the junction, and increases in prevalence and length with age. These characteristics of cardiac mucosa make it highly unlikely that it is a normal structure. We develop the hypothesis that cardiac mucosa represents an early histologic manifestation of gastroesophageal reflux.

Distribution and Significance of Epithelial Types in Columnar-lined Esophagus

An abnormal columnar-lined esophagus (CLE) is characterized by the presence of cardiac mucosa (CM), oxynto-cardiac mucosa (OCM), and intestinal metaplastic epithelium (IM) between gastric oxyntic mucosa and esophageal squamous epithelium. Thirty-two patients with CLE measuring 2–16 cm long had 5–37 biopsies per patient that showed CM, OCM, or IM for a total of 424 biopsies. Detailed mapping of the distribution of epithelial types within the CLE showed a distinct zonation of epithelial types; CM was present throughout the CLE, whereas OCM and IM tended to occur in the distal and proximal part of the CLE, respectively. All 32 patients (64 of 68 biopsies) showed IM at the most proximal level, compared with 22 of 32 patients (40 of 102 biopsies) in the most distal level biopsies. The density of goblet cells was highest in the most proximal level. The differences in prevalence and density of goblet cells between most proximal and most distal level biopsies were highly significant. These data suggest that for a given number of biopsies within the CLE, the likelihood of finding IM is greatest when the biopsies are concentrated in the most proximal area of the CLE. We suggest that glandular transformation of squamous epithelium results in CM, which evolves into OCM and IM by development of specialized parietal cells and goblet cells, respectively. The severity and nature of reflux cause these epithelial transformations in a constant and predictable manner. Recognition of these changes permits the development of morphologic definitions of reflux disease and the characterization of the sequence of epithelial changes that represent the reflux–adenocarcinoma sequence.

High intraepithelial eosinophil counts in esophageal squamous epithelium are not specific for eosinophilic esophagitis in adults.

OBJECTIVESThe histologic criterion of >20 eosinophils per high power field (hpf) is presently believed to establish the diagnosis of idiopathic eosinophilic esophagitis (IEE). This is based on data that the number of intraepithelial eosinophils in gastroesophageal reflux disease (GERD) is less than 20/hpf. This study tests this belief.METHODSPathology records were searched for patients who had an eosinophil count >20/hpf in an esophageal biopsy. This patient population was biased toward adults with GERD who had routine multilevel biopsies of the esophagus. The clinical, radiological, and manometric data and biopsies were studied.RESULTSForty patients out of a total of 3,648 reports examined had an eosinophil count >20/hpf in squamous epithelium of an esophageal biopsy. Analysis of these 40 cases indicated that 6 (15%) patients had IEE, 2 (5%) had coincident IEE and GERD, 28 (70%) had GERD, and 2 (5%) each had achalasia and diverticulum. There was no significant difference among these groups in terms of maximum eosinophil number, biopsy levels with >20 esoinophils/hpf, presence of eosinophilic microabscesses, involvement of surface layers by eosinophils, and severity of basal cell hyperplasia and dilated intercellular spaces.CONCLUSIONAll histologic features presently ascribed to IEE can occur in other esophageal diseases, notably GERD. As such, the finding of intraepithelial eosinophilia in any number is not specific for IEE. When a patient with GERD has an esophageal biopsy with an eosinophil count >20/hpf, it does not mean that the patient has IEE.

Stereotactic biopsy in the diagnosis of brain masses: comparison of results of biopsy and resected surgical specimen.

We report the pathological accuracy of image-directed stereotactic brain biopsy in 30 patients who had mass lesions of the brain and subsequently underwent resection of the mass. The histological diagnosis at stereotactic biopsy was appropriate for direction of clinical management in 28 of 30 patients. Correlation between the stereotactic and resection diagnoses was exact in 19 of 30 cases. These included 11 of 12 nonastrocytic neoplasms and 8 of 13 astrocytic neoplasms. Correlation was imperfect in 9 of 30 cases, but not to the extent of having significant clinical impact. These included 2 cases of anaplastic astrocytoma that were upgraded to glioblastoma multiforme, 2 cases of astrocytoma that had a significant oligodendroglial component, and 5 non-neoplastic lesions that were reported on biopsy as showing nonspecific reactive changes. In 2 of 30 patients, the stereotactic biopsy was not accurate. This included one patient who had glioblastoma multiforme whose stereotactic biopsy showed only necrotic tissue. Serious diagnostic error that resulted in clinical mismanagement occurred in one patient who had a pineal germinoma that had large areas of granulomatous inflammation at which the stereotactic biopsy was directed. This study provides evidence that, with careful target placement, stereotactic biopsy can provide biopsy material that represents the entire lesion with an accuracy that is sufficient for clinical management.

Definition of histopathologic changes in gastroesophageal reflux disease

A series of 71 patients with multiple measured biopsies of the gastroesophageal junctional region permitting assessment of the presence and length of different glandular epithelial types is presented. All but nine of 53 patients in whom a 24-hour pH study was performed had abnormal reflux, suggesting that endoscopic recognition of an abnormal columnar mucosa at the gastroesophageal junction sufficient to precipitate multiple-level biopsies indicates a high probability of abnormal reflux. All patients had cardiac mucosa (CM) or oxyntocardiac mucosa (OCM). CM was present in 68 of 71 patients. The prevalence of intestinal metaplasia increased with increasing CM+OCM length, and was present in all 22 patients with a CM+OCM length >2 cm and in 20 of 49 patients with a CM+OCM length <2 cm. Patients with a CM+OCM length >2 cm had a markedly higher acid exposure than patients with a CM+OCM length <2 cm. The findings suggest that the presence of CM and OCM in the junctional region are predictive of abnormal acid exposure, and that increasing OCM+CM length correlates strongly with the amount of acid exposure. The histologic finding of CM and OCM represents a sensitive histologic criterion for gastroesophageal reflux rather than normal epithelia. These diagnostic criteria represent the first useful histologic definitions for assessing the presence and severity of reflux.

Emphysematous Pyelonephritis: A 5-Year Experience with 13 Patients

Emphysematous pyelonephritis is a life-threatening necrotizing renal infection characterized by the production of gas. Of 8,105 admissions to our diabetes service during the last 5 years we identified 13 cases. The patients were managed aggressively with fluids and antibiotics, followed by immediate nephrectomy. The mortality rate is 40 to 50 per cent, primarily owing to sudden septic complications.

Barrett's esophagus can and does regress after antireflux surgery: A study of prevalence and predictive features

BACKGROUND To investigate the factors leading to histologic regression of metaplastic and dysplastic Barretts esophagus (BE). STUDY DESIGN The study sample consisted of 91 consecutive patients with symptomatic Barretts esophagus. Pre- and posttreatment endoscopic biopsies from 77 Barretts patients treated surgically and 14 treated with proton pump inhibitors (PPI) were reviewed. An expert pathologist confirmed the presence of intestinal metaplasia (IM) with or without dysplasia. Posttreatment histology was classified as having regressed if two consecutive biopsies taken more than 6 months apart plus all subsequent biopsies showed loss of IM or loss of dysplasia. Clinical factors associated with regression were studied by multivariate analysis, as was the time course of its occurrence. RESULTS Histopathologic regression occurred in 28 of 77 patients (36.4%) after antireflux surgery and in 1 of 14 patients (7.1%) treated with PPIs alone (p < 0.03). After surgery, regression from low-grade dysplastic to nondysplastic BE occurred in 17 of 25 patients (68%) and from IM to no IM in 11 of 52 (21.2%). Both types of regression were significantly more common in short (< 3 cm) than long (> 3 cm) segment Barretts esophagus; 19 of 33 (58%) and 9 of 44 (20%) patients, respectively (p = 0.0016). Eight patients progressed, five from IM alone to low-grade dysplasia and three from low- to high-grade dysplasia. All those who progressed had long segment BE. On multivariate analysis, presence of short segment Barretts and type of treatment were significantly associated with regression; age, gender, surgical procedure, and preoperative lower esophageal sphincter and pH characteristics were not. The median time of biopsy-proved regression was 18.5 months after surgery, with 95% occurring within 5 years. CONCLUSIONS This study refutes the widely held assumption that once established, Barretts esophagus does not change. More than one-third of patients with visible segments of Barretts esophagus undergo histologic regression after antireflux surgery. Regression is dependent on the length of the columnar-lined esophagus and time of followup after antireflux surgery.

Controversies of the cardiac mucosa and Barrett's oesophagus

Confusion regarding the diagnosis of Barretts oesophagus exists because of a false dogma that cardiac mucosa is normally present in the gastro‐oesophageal junctional region. Recent data indicate that the only normal epithelia in the oesophagus and proximal stomach are squamous epithelium and gastric oxyntic mucosa. When this fact is recognized, it becomes easy to develop precise histological definitions for the normal state (presence of only squamous and oxyntic mucosa), metaplastic oesophageal columnar epithelium (cardiac mucosa with and without intestinal metaplasia, and oxynto‐cardiac mucosa), the gastro‐oesophageal junction (the proximal limit of gastric oxyntic mucosa), the oesophagus (that part of the foregut lined by squamous and metaplastic columnar epithelium), reflux disease (the presence of metaplastic columnar epithelium), and Barretts oesophagus (cardiac mucosa with intestinal metaplasia). It is also possible to assess accurately the severity of reflux which is directly proportional to the amount of metaplastic columnar epithelium, and the risk of adenocarcinoma which is related to the amount of dysplasia in intestinal metaplastic epithelium present within the columnar lined segment of the oesophagus. Histopathological precision cannot be matched by any other modality and can convert the confusion that exists regarding diagnosis of Barretts oesophagus to complete lucidity in a manner that is simple, accurate, and reproducible.

Histologic classification of patients based on mapping biopsies of the gastroesophageal junction.

This study consists of 959 consecutive patients in whom endoscopic biopsies were taken according to a protocol that permitted mapping and measurement of epithelial types in the gastroesophageal region. The epithelial types were classified as normal (oxyntic and squamous) and questionably abnormal (oxyntocardiac, cardiac, intestinal) by strict histologic criteria. Patients were classified into four groups based on the length of histologically defined abnormal glandular epithelium in the measured biopsies. A total of 811 (84.6%) patients had 0 to 0.9 cm of questionably abnormal columnar epithelium between normal oxyntic mucosa and squamous epithelium. Of these, 161 (19.9%) patients had no abnormal epithelium, 158 (19.4%) patients had oxyntocardiac mucosa, 372 (45.9%) patients had cardiac mucosa, and 120 (14.8%) patients had intestinal metaplasia. A total of 148 (15.4%) patients had ≥1 cm of abnormal columnar epithelium. All but one patient in this group had cardiac or intestinal epithelia. The prevalence of intestinal epithelium increased progressively with increasing length of abnormal columnar epithelium, being present in 70.4% in the 1- to 2-cm group, 89.5% in the 3- to 4-cm group, and 100% with in the ≥5 cm group. We propose a histologic grading system of biopsies based on these findings.