Distribution and central projections of primary afferent neurons that innervate the masseter muscle and mandibular periodontium: a double-label study.

A double-label strategy was used to determine the distribution and central projections of primary afferent neurons that innervate the periodontium and muscles of mastication in cats. Central injections of either Fast Blue (FB) or a mixture of wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) and HRP were made into one of three cytoarchitectonically distinct regions of the spinal trigeminal nucleus. These regions included the subnucleus oralis (Vo), the subnucleus interpolaris (Vi), and the medullary dorsal horn (MDH). In each case, injections were also made into the periodontium of the ipsilateral mandibular teeth or into the ipsilateral masseter muscle. FB injections preceded the peroxidase injections by at least 48 hours and total survival time ranged from 72 to 96 hours. Animals were perfused with phosphate-buffered paraformaldehyde (4%; pH 7.2). Serial frozen sections were made through the brainstem and trigeminal ganglion. Tetramethylbenzidine was used as a chromagen to demonstrate HRP and sections were viewed with brightfield and epifluorescent illumination. Cells containing peripherally injected tracer were observed in the lateral portion of the ganglion and in the mesencephalic nucleus (Vmes). Double-labeled ganglion cells were observed in most cats that received periodontal injections in combination with central injections in the dorsal part of spinal trigeminal nucleus regardless of the rostrocaudal level of the central injection. In the animals that received intramuscular injections, double-labeled ganglion cells were observed only in the animals that received central injections caudal to the Vo. Double-labeled Vmes perikarya were observed in cats that received either intramuscular or periodontal injections in combination with central injections into the MDH and Vo but not in animals that received injections into the Vi. These results demonstrate that ganglion cell periodontal afferents project to the three major rostrocaudal subdivisions of the spinal trigeminal nucleus while ganglion cell muscle afferents have more limited central projections to caudal regions of the nucleus. Masseter and periodontal Vmes afferents also project ot the spinal trigeminal nucleus--specifically, to the Vo and MDH. These findings are consistent with physiological observations regarding the role of periodontal and masseteric afferents in oral and facial reflexes and somesthetic mechanisms.

Prospective correlation of cervicovaginal cytologic and histologic specimens.

An effective, prospective, computer-guided method of correlation is reported. The mechanism for identification of cases, comparison of diagnoses, and reconciliation of discrepancies are explained. The results are similar to prior, retrospective, correlation studies. The benefits specific to this unique prospective approach include optimal capture of cases for correlation, minimization of errors before diagnoses are released to clinicians and patients, and internal standardization of diagnostic criteria. Three thousand four hundred and four consecutive paired cervicovaginal cytologies and biopsies were accessioned at the Pathology Department of Duke University Medical Center over a 43-month period. Of these, 481 paired cases (14%) had discordant diagnoses, defined as differing more than one degree of dysplasia or as dysplasia or carcinoma identified by only one modality. Additional evaluation reconciled the diagnostic differences in 35 cases. Eighteen initial diagnostic differences arose from cytologic screening errors, 16 from interpretive errors by staff pathologists, and one from superficial initial histologic sections. The remaining 446 discordances were attributed to sampling differences. The cytologic smear contained the diagnostic lesion in 40% of the cases and the biopsy the remainder, emphasizing the utility of pairing these sampling techniques in patients at risk for dysplasia.

Intrapericardial foregut cyst associated with intrauterine death.

Intrapericardial developmental foregut cysts are rare and are most frequently incidental findings at necropsy in adults. A 29 year old Asian woman delivered a 24 week stillborn fetus seven days after diagnosis of intrauterine death caused by rupture of a foregut cyst. Multiple cysts occupied the wall of the right atrium and its rupture caused haemopericardium and cardiac tamponade.

Cytomegalovirus sialadenitis in patients with the acquired immunodeficiency syndrome: a potential diagnostic pitfall with fine-needle aspiration cytology.

We report three cases of cytomegalovirus (CMV) sialadenitis which presented as parotid gland nodules in patients infected with the human immunodeficiency virus. While CMV is known to widely infect patients with the acquired immunodeficiency syndrome (AIDS), we are aware of only a single report of CMV sialadenitis in a patient with AIDS (Pialoux et al.: Rev Infect Dis 1991;13:338). Utilizing fine-needle aspiration (FNA) cytology as the initial investigative modality, two cases were correctly diagnosed preoperatively while the third case displayed atypical features and was interpreted erroneously as carcinoma leading to surgical intervention. Upon review of these cases of CMV sialadenitis, the characteristic intranuclear inclusions are best identified with Papanicolaou (Pap) staining. CMV sialadenitis should be considered in the differential diagnosis of painless salivary gland enlargement in patients with AIDS. We believe this lesion can be diagnosed preoperatively with FNA and the interpretation is aided by evaluating both Pap- and Giemsa-stained material.

Clinical significance of an inconclusive cytopathologic diagnosis: a five-year experience at Duke University Medical Center. II. Analysis and follow-up of specimens from the respiratory tract.

OBJECTIVE: As a follow-up of our initial report, we critically examined a selected number of cases from the respiratory tract with an original diagnosis of "atypical cells present suspicious for malignancy" in order to ascertain if any particular features of the specimen or the atypical cells were predictors of malignancy. STUDY DESIGN: From a total of 563 such cases, 31 were identified with subsequent histologic findings of a nonneoplastic pathologic process. An additional 45 cytologic cases were randomly selected to represent those with subsequent histologic findings confirming the suspicion of malignancy. All the cytologic specimens were examined without knowledge of the histologic follow-up results. RESULTS: Analysis of the cellular composition of the specimens identified no discernible difference between specimens from benign and malignant processes. Quantitative analysis of the atypical cells and qualitative assessment of the nuclear abnormalities revealed that marked nuclear hyperchromasia and a very high nuclear/cytoplasmic ratio were more likely to represent a malignant process. However, none of the parameters examined could consistently predict the presence or absence of malignancy. CONCLUSION: When a single cytologic specimen is inconclusive as to the presence or absence of malignancy, standard cytologic criteria cannot reliably predict a malignant process.

Clinical significance of an inconclusive cytopathologic diagnosis. I. Positive predictive value.

We retrospectively analyzed the pathology database of 1,057 patients at Duke University Medical Center who received an inconclusive cytopathologic diagnosis during the five-year period 1984-1989 in an attempt to answer the question, what is the significance of a cytopathologic diagnosis of "atypical cells are present that are suspicious for, but not diagnostic of, malignancy?" We identified 1,110 cytologic specimens from all body sites receiving this diagnosis, and of them, 805 (73%) had a follow-up specimen from the same anatomic site that was definitive as to the presence or absence of malignancy; 305 (27%) had no follow-up specimen. Of the follow-up specimens, 596 (74%) were histopathologic specimens, and 209 (26%) were cytopathologic. Specimens from the respiratory tract accounted for 51% (563) of the cases, and the positive predictive value (PPV) of an inconclusive diagnosis at this site was 85%. Of the remaining specimens, those from the urinary (10%) and genital (8%) tracts were the most common, and the PPVs of an inconclusive diagnosis at these sites were 83% and 61%, respectively. The overall PPV of an inconclusive cytologic diagnosis from all body sites was 80% and ranged between 57% and 93%, depending on the anatomic site.

Accuracy and morphologic aspects of pancreatic and biliary duct brushings.

One hundred eight brushing cytology specimens with adequate follow-up were obtained from strictures of the biliary and pancreatic ducts. The material was classified as benign, reactive, low grade dysplasia, high grade dysplasia or adenocarcinoma. A diagnosis of carcinoma was made in 18 patients, high grade dysplasia in 12, low grade dysplasia in 6 and benign, nonneoplastic in the remaining cases. The diagnostic sensitivity for carcinoma was 44%, with a specificity of 98%. Ten of 12 patients with high grade dysplasia demonstrated other evidence of carcinoma. No complications were encountered. Brushing cytodiagnosis of extrahepatic biliary and pancreatic duct strictures appears to be a safe procedure, with high specificity but only modest sensitivity.

Physiological identification of jaw-movement-related neurons in the trigeminal nucleus of cats.

Although neurons responsive to jaw movements have been identified in most parts of the trigeminal brainstem nuclei, little is known about how this information is relayed to the thalamus and ultimately to the cortex for kinesthetic functions and sensorimotor integration. The present extracellular recording experiments showed that a substantial amount of movement-related information is relayed to the thalamus through the caudal part of subnucleus interpolaris (Vi) in adult cats. Vertical jaw displacements, natural mechanical stimuli, and electrical stimulation of the masseter nerve were used to determine the receptive fields and response properties of movement-related neurons. Movement-related responses were observed in 161 units. The receptive fields of these units were located in the masseter muscle, other deep structures, hairy skin, oral mucosa, or some combination of these structures (i.e., convergent). The latency of units responding to masseter nerve stimulation ranged from 1.0 msec to 20 msec, which suggested that some movement-related information was provided by smaller-diameter muscle afferents. Movement responses were either tonic or phasic. Tonic units showed continuous firing at some jaw position; some of these showed a "dynamic" response to jaw displacement. Phasic units were only active, or showed increased activity, when the jaw moved through a specific position. Seventy-one movement-related units were activated by stimulation from the contralateral ventroposteromedial nucleus (VPM) of the thalamus. Most of the brainstem recording sites were located in the dorsal part of Vi between the caudal pole of the facial motor nucleus and the obex. Neurons in caudal Vi may be important for facial kinesthesia.(ABSTRACT TRUNCATED AT 250 WORDS)

Paroxysmal cold hemoglobinuria associated with non-Hodgkin's lymphoma.

This report describes a patient with severe unexplained recurrent hemolytic anemia and congestive heart failure. Donath-Landsteiner antibodies, suggestive of paroxysmal cold hemoglobinuria (PCH), were detected. On postmortem examination, a diagnosis of non-Hodgkin's lymphoma, primarily involving the heart, was made. This previously undescribed association expands on the clinical and serologic spectrum of non-Hodgkin's lymphoma and PCH. Unexplained hemolytic anemia in the elderly should raise the suspicion of an underlying lymphoproliferative disorder.

An in vitro, randomized, prospective study to maximize cellular yield during bile duct brush cytology.

Endoscopic retrograde brush cytology is useful for the evaluation of biliary strictures. Access across a stricture can be maintained by removing the cytology brush while leaving the sheath in the bile duct. We examined the potential for loss of diagnostic cellular material in this setting using the canine biliary system. Twenty consecutive samples were randomly collected by (1) pushing the brush from the end of the sheath or (2) pulling the brush through the length of the sheath. Slides prepared from cell suspensions were scored by a cytopathologist blinded to the collection method. Pulling the brush resulted in a significant loss of cellular material (p < 0.001). In a second phase, 23 consecutive samples were randomly obtained in the same fashion. Combining salvage cytology of material from the sheath with cytology of the pulled-brush specimens produced cellular yields similar to those of specimens obtained by pushing the brush from the sheath. If the brush is pulled from the sheath during bile duct brush cytology, we suggest that salvage cytology be performed in order to maximize the diagnostic sensitivity.