Plexiform lesions are a network of vascular channels lined by endothelial cells with a core of myofibroblasts or less-differentiated cells and are associated with expansion and partial destruction of the arterial wall with extension of the plexiform lesion into the perivascular connective tissue.
Constrictive and complex arteriolar lesions in pulmonary arterial hypertension--plexiform (network of vascular channels lined by endothelial cells with a core of myofibroblasts or less well differentiated cells) and dilation lesion (thin-wall, veinlike vessels distal to plexiform lesion with angiomatoid features) (hematoxylin-eosin, original magnification X80).
The Grade V lesion, otherwise known as the plexiform lesion, remains the pathologic hallmark of clinical PH, and a variety of hypotheses have been offered to explain its pathogenesis.
The histopathologic severity of vascular lesions associated with PH in SCD has also been debated in the autopsy literature, with the hallmark Grade V plexiform lesion being recognized by one series in 12 of 20 patients (60%)" but in only 1 of 21 patients (0.
Neurofibromatosis type 1 can cause conductive hearing loss when it invades the ear canal as a plexiform lesion in the preauricular area.
The disease can manifest as one of several types of lesions, including cafe au lair spots, cutaneous tumors, plexiform lesions, axillary freckling, Lisch nodules of the iris, optic gliomas, and bony abnormalities.
The vascular changes, which included medial and intimal thickening, angioblastic proliferation, plexiform lesions
, and dilation lesions, occur in a setting of hypoxia, chronic inflammation, and high pressure and flow via a systemic arterial supply (7).
Solitary lesions may be very well defined; plexiform lesions
are ill defined and infiltrative.
Eleven percent had medial hypertrophy and intimal fibrosis without plexiform lesions
, 7% had pulmonary veno-occlusive disease, and 4% had in situ thrombosis as the prominent histologic finding.
, which are frequently seen in other forms of pulmonary hypertension, are not observed in PCH.
In this clinical setting, the plexiform-like lesions could not be clearly discriminated from recanalized thrombi, (14) therefore they were not regarded as being identical to the plexiform lesions
of primary PH.
4] In another series of radiographic and histopathologic examination of 20 patients with pulmonary hypertension, cholesterol granulomas were found in 5 cases, but no association with plexiform lesions